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Selected AbstractsAddition of insulin lispro protamine suspension or insulin glargine to oral type 2 diabetes regimens: a randomized trialDIABETES OBESITY & METABOLISM, Issue 10 2010K. Strojek Aims: The addition of basal insulin to existing oral therapy can help patients with type 2 diabetes (T2D) achieve glycaemic targets. This study compares the efficacy and safety of insulin lispro protamine suspension (ILPS) and insulin glargine in insulin-naive patients with T2D and inadequate control on oral antihyperglycaemic medication (OAM). Materials and Methods: An open-label, randomized, multicentre, multinational 24-week study of 471 patients receiving ,2 OAMs for ,3 months with a body mass index between 25 and 45 kg/m2 and HbA1c 7.5,10.0% was conducted. ILPS was injected once or twice daily vs. glargine injected once daily plus prestudy OAMs. Primary objective compared the HbA1c change from baseline. Results: HbA1c change from baseline to endpoint was similar in both groups [,1.46% (ILPS) and ,1.41% (glargine)]. Least-squares mean difference (95% CI) for HbA1c (,0.05 [,0.21, 0.11]%), glycaemic variability (0.06 [,0.06, 0.19] mmol/l) and weight change (,0.01 [,0.61, 0.59] kg) showed non-inferiority (margins of 0.4%, 0.8 mmol/l and 1.5 kg, respectively). Percentages of patients achieving HbA1c <7.0% were 43.8% ILPS and 41.2% glargine. Mean daily insulin dose was 0.39 vs. 0.35 U/kg (p = 0.02) and weight gain was 1.04 vs. 1.07 kg for ILPS vs. glargine (p = 0.98). Overall hypoglycaemia (episodes/patient/year) was similar for ILPS and glargine (24.2 ± 28.8 vs. 23.0 ± 30.9); nocturnal (6.1 ± 10.6 vs. 4.1 ± 9.4, p < 0.001) rates were higher for ILPS. Severe hypoglycaemia was higher for ILPS vs. glargine (n = 9 vs. n = 2; p = 0.04). Conclusions: At endpoint, ILPS was non-inferior to glargine in HbA1c change from baseline, but associated with increased risk of hypoglycaemia. [source] Response of refractory colitis to intravenous or oral tacrolimus (FK506)INFLAMMATORY BOWEL DISEASES, Issue 5 2002Dr. Klaus Fellermann Abstract Intravenous cyclosporine has proven to be an alternative to emergency colectomy in steroid-refractory ulcerative colitis, whereas the experience with FK506 is limited. In this report we compare intravenous to oral FK506 treatment in 38 patients with refractory ulcerative (n = 33) or indeterminate (n = 5) colitis. FK506 was started intravenously in the first group (n = 18) at a dose of 0.01 to 0.02 mg/kg up to 14 days, followed by 0.1 to 0.2 mg/kg orally, or was started orally at this dose in a second group (n = 20). Additional azathioprine/6-mercaptopurine was given and steroids were tapered in responding patients, followed by a dose reduction of FK506. Clinical disease activity and laboratory parameters were assessed to evaluate efficacy and safety. Primary objectives were the induction of remission (Truelove index of mild) and colectomy-free survival. Treatment lasted for a mean of 7.6 months, and the mean observation period was 16.2 months. Eighteen of 38 patients improved within 14 days, and a complete remission was achieved in 13 patients after 1 month. A colectomy within 1 month was performed in 3 of 38 patients. The overall colectomy rate was 34%. One-half of the patients with a minimum follow-up of 2 years required a colectomy. Intravenous and per oral administration were equally safe and effective. The most frequent adverse events included tremor, hyperglycemia, hypertension, and infection, but none were severe. Renal impairment was rare and subsided upon drug withdrawal. In conclusion, FK506 is effective in the treatment of refractory colitis with per oral dosing being equivalent to intravenous administration. [source] Study of bioaccumulation of dalteparin at a prophylactic dose in patients with various degrees of impaired renal functionJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 4 2009P. SCHMID Summary.,Background: Low-molecular-weight heparins (LMWH) have been shown to be effective and safe for prophylaxis of thromboembolic diseases. However, issues regarding safety and optimal use of LMWH arise in patients with renal insufficiency (RI). Objectives: To compare pharmacokinetic data of dalteparin for up to 3 weeks in patients with various degrees of RI. Patients and methods: Patients from general medical and surgical wards were included in this prospective cohort study and divided into three groups according to renal function: A = normal (GFR , 60 mL min,11.73 m,2), B = mild RI (GFR 30,59 mL min,11.73 m,2), C = severe RI (GFR < 30 mL min,11.73 m,2). Dalteparin was injected s.c. once daily at a prophylactic dose. Peak anti-Xa activity levels (anti-Xa) were measured 4 ± 1 h after injection on day 1 and every third day up to 3 weeks. Primary objectives were peak anti-Xa levels and adjusted anti-Xa levels, adjustment being carried out for dose and body weight. Results: A total of 42 patients could be analyzed during a median of 10 days (interquartile range IQR 4,13, range 1,20). In all groups, adjusted peak anti-Xa levels were not different on day 10 compared with day 1. No bioaccumulation >30% could be found up to day 10 even in patients with severe RI. Conclusion: The use of dalteparin at a prophylactic dose was not associated with a bioaccumulation >30% even in patients with severe renal insufficiency during a median follow-up of 10 days (IQR 4,13, range 1,20). [source] Phase I study of paclitaxel with standard dose ifosfamide in children with refractory solid tumors: A Pediatric Oncology Group study (POG 9376)PEDIATRIC BLOOD & CANCER, Issue 3 2009James I. Geller MD Abstract Purpose A dose-escalation Phase I study of taxol (paclitaxel) administered in combination with standard dose ifosfamide was conducted in children with relapsed or refractory solid tumors. Primary objectives were to estimate the maximum tolerated dose (MTD) and to describe the dose-limiting toxicities (DLTs). Patients and Methods Paclitaxel was administered as a 6-hr continuous infusion (hr 0,6), followed by intravenous ifosfamide (2 g/m2/day,×,3 days) over 1 hr at hours 6,7, 24,25, and 48,49. Patients at dose level 1 received 250 mg/m2 paclitaxel. Subsequent dose escalation proceeded using a standard 3,×,3 Phase I design. Results Fifteen patients received a combined 46 courses of therapy. The median age was 14.5 years (range, 2,19 years), and diagnoses included sarcoma (7), neuroblastoma (3), and other (5). Three patients received paclitaxel at 250 mg/m2 (10 courses), six at 325 mg/m2 (19 courses), three at 425 mg/m2 (8 courses), and three at 550 mg/m2 (9 courses). DLTs occurred in 2/3 patients at 550 mg/m2 paclitaxel during cycle 1, including grade 3 hypotension and grade 4 anaphylaxis in 1 patient each. Common non-dose-limiting toxicities included bone marrow suppression and peripheral neuropathy. Response was evaluable in 14 patients and included mixed response (3), stable disease (5), and progressive disease (6). Conclusion Paclitaxel hypersensitivity reactions were dose limiting when the drug was administered as a 6-hr infusion. The MTD and recommended Phase II dose of paclitaxel administered as a 6-hr continuous intravenous infusion followed by standard dose intravenous ifosfamide is 425 mg/m2 paclitaxel. Pediatr Blood Cancer 2009;52:346,350. © 2008 Wiley-Liss, Inc. [source] Enabling interactive and collaborative oil reservoir simulations on the GridCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 11 2005Manish Parashar Abstract Grid-enabled infrastructures and problem-solving environments can significantly increase the scale, cost-effectiveness and utility of scientific simulations, enabling highly accurate simulations that provide in-depth insight into complex phenomena. This paper presents a prototype of such an environment, i.e. an interactive and collaborative problem-solving environment for the formulation, development, deployment and management of oil reservoir and environmental flow simulations in computational Grid environments. The project builds on three independent research efforts: (1) the IPARS oil reservoir and environmental flow simulation framework; (2) the NetSolve Grid engine; and (3) the Discover Grid-based computational collaboratory. Its primary objective is to demonstrate the advantages of an integrated simulation infrastructure towards effectively supporting scientific investigation on the Grid, and to investigate the components and capabilities of such an infrastructure. Copyright © 2005 John Wiley & Sons, Ltd. [source] Libertarian Free Will and CNC ManipulationDIALECTICA, Issue 3 2001Ishtiyaque Haji An agent who is the victim of covert and nonconstraining control (CNC) is unaware of being controlled and controllers get their way by manipulating the victims so that they willingly do what the controllers desire. Our primary objective is to argue that if cases of CNC manipulation undermine compatibilist accounts of the sort of control required for moral responsibility, they also undermine various agent-causal and non-agent-causal libertarian accounts as well. [source] Temporal coherence of aboveground net primary productivity in mesic grasslandsECOGRAPHY, Issue 3 2008Jana L. Heisler Synchrony in ecological variables over wide geographic areas suggests that large-scale environmental factors drive the structure and function of ecosystems and override more local-scale environmental variation. Described also as coherence, this phenomenon has been documented broadly in the ecological literature and has recently received increasing attention as scientists attempt to quantify the impacts of global changes on organisms and their habitats. Using a mesic grassland site in North America, we assessed coherence in ecosystem function by quantifying similarity in aboveground net primary production (ANPP) dynamics in 48 permanent sampling locations (PSLs) over a 16-yr period. Our primary objective was to characterize coherence across a broad geographic region (with similar ecosystem structure and function), and we hypothesized that precipitation and a similar fire frequency would strengthen coherence between PSLs. All 48 PSLs at our site (Konza Prairie Biological Station, Manhattan, KS, USA; KPBS) were exposed to a similar regional driver of ANPP (precipitation); however, local drivers (including differences in fire frequency and soil depth at different topographic positions) varied strongly among individual PSLs. For the purpose of this assessment, the watershed-level experimental design of KPBS was considered a model, which represented different fire management strategies across the Great Plains Region. Our analyses revealed a site-level (KPBS) coherence in ANPP dynamics of 0.53 for the period of 1984,1999. Annual fire enhanced coherence among PSLs to 0.76, whereas less frequent fire (fire exclusion or a 4-yr fire return interval) failed to further increase coherence beyond that of the KPBS site level. Soil depth also strongly influenced coherence among PSLs with shallow soils at upland sites showing strong coherence across fire regimes and annually burned uplands closely linked to annual precipitation dynamics. The lack of coherence in ecosystem function in PSLs with deep soils and low fire frequencies suggests that conservation and management efforts will need to be more location specific in such areas where biotic interactions may be more important than regional abiotic drivers. [source] Influences of the vegetation mosaic on riparian and stream environments in a mixed forest-grassland landscape in "Mediterranean" northwestern CaliforniaECOGRAPHY, Issue 4 2005Hartwell H. Welsh We examined differences in riparian and aquatic environments within the three dominant vegetation patch types of the Mattole River watershed, a 789-km2 mixed conifer-deciduous (hardwood) forest and grassland-dominated landscape in northwestern California, USA. Riparian and aquatic environments, and particularly microclimates therein, influence the distributions of many vertebrate species, particularly the physiologically-restricted ectotherms , reptiles and amphibians (herpetofauna), and fishes. In addition to being a significant portion of the native biodiversity of a landscape, the presence and relative numbers of these more tractable small vertebrates can serve as useful metrics of its "ecological health." Our primary objective was to determine the range of available riparian and aquatic microclimatic regimes, and discern how these regimes relate to the dominant vegetations that comprise the landscape mosaic. A second objective, reported in a companion paper, was to examine relationships between available microclimatic regimes and herpetofaunal distributions. Here we examined differences in the composition, structure, and related environmental attributes of the three dominant vegetation types, both adjacent to and within the riparian corridors along 49 tributaries. Using automated dataloggers, we recorded hourly water and air temperatures and relative humidity throughout the summer at a representative subset of streams; providing us with daily means and amplitudes for these variables within riparian environments during the hottest period. Although the three vegetation types that dominate this landscape each had unique structural attributes, the overlap in plant species composition indicates that they represent a seral continuum. None-the-less, we found distinct microclimates in each type. Only riparian within late-seral forests contained summer water temperatures that could support cold-water-adapted species. We evaluated landscape-level variables to determine the best predictors of water temperature as represented by the maximum weekly maximum temperature (MWMT). The best model for predicting MWMT (adj. R2=0.69) consisted of catchment area, aspect, and the proportion of non-forested (grassland) patches. Our model provides a useful tool for management of cold-water fauna (e.g. salmonids, stream amphibians) throughout California's "Mediterranean" climate zone. [source] Movement patterns of endangered Roanoke logperch (Percina rex)ECOLOGY OF FRESHWATER FISH, Issue 3 2008J. H. Roberts Abstract,,, Using mark,recapture methods, we studied movements of endangered Roanoke logperch (Percina rex Jordan & Evermann), a benthic darter, at 12 riffle,run sites over a 9-year-long period in the Roanoke River, Virginia, USA. Our primary objective was to characterise movements among transects within sites, but we opportunistically recorded two between-site movements as well. Our recapture rate was low (22 of 485 marked fish), but most recaptured fish exhibited movements between tagging and recapture, relocating either to another transect within a site (12 fish) or to another site altogether (two fish). Within sites, Roanoke logperch exhibited fidelity over time to the areas in which they were initially marked. These restricted areas were lengthier than transects (>15 m) but shorter than entire riffle,runs (<150 m). The two between-site movements were extensive (3.2 and 2.5 km), observed over a long mark,recapture interval (2 and 5 years, respectively), and may have represented migratory or dispersal movements. Their detection required an unusually extensive study design. Both small- and large-scale movements fulfil important ecological functions for Roanoke logperch, and greater study of such movements in this and other darter species is needed to inform conservation choices. [source] Phospho-proteomic immune analysis by flow cytometry: from mechanism to translational medicine at the single-cell levelIMMUNOLOGICAL REVIEWS, Issue 1 2006Omar D. Perez Summary:, Understanding a molecular basis for cellular function is a common goal of biomedicine. The complex and dynamic cellular processes underlying physiological processes become subtly or grossly perturbed in human disease. A primary objective is to demystify this complexity by creating and establishing relevant model systems to study important aspects of human disease. Although significant technological advancements over the last decade in both genomic and proteomic arenas have enabled progress, accessing the complexity of cellular interactions that occur in vivo has been a difficult arena in which to make progress. Moreover, there are extensive challenges in translating research tools to clinical applications. Flow cytometry, over the course of the last 40 years, has revolutionized the field of immunology, in both the basic science and clinical settings, as well as having been instrumental to new and exciting areas of discovery such as stem cell biology. Multiparameter machinery and systems exist now to access the heterogeneity of cellular subsets and enable phenotypic characterization and functional assays to be performed on material from both animal models and humans. This review focuses primarily on the development and application of using activation-state readouts of intracellular activity for phospho-epitopes. We present recent work on how a flow cytometric platform is used to obtain mechanistic insight into cellular processes as well as highlight the clinical applications that our laboratory has explored. Furthermore, this review discusses the challenges faced with processing high-content multidimensional and multivariate data sets. Flow cytometry, as a platform that is well situated in both the research and clinical settings, can contribute to drug discovery as well as having utility for both biomarker and patient-stratification. [source] Britain, EMU and the European economyINDUSTRIAL RELATIONS JOURNAL, Issue 4 2000Steve Bradley In January 1999, 11 member countries of the European Union ,irrevocably' locked the foreign exchange values of their currencies to the euro, and they committed themselves to abandon their currencies in favour of the euro in 2002. As a result, these countries ceased to operate independent monetary policies. Monetary policy for the whole euro-zone became the responsibility of the European Central Bank (ECB), whose primary objective is to maintain a low and stable rate of price inflation for the euro currency. The rules governing Economic and Monetary Union (EMU) were laid down in the treaty of Maastricht in 1992. As conditions for entry to EMU, the treaty specified ,convergence criteria' which consisted of upper limits for several macroeconomic aggregates including, notably, a 3 per cent maximum for the ratio of the public sector deficit to GDP and 60 per cent for the ratio of public debt to GDP.1 In February 1998 the 11 applicant countries submitted statistical analyses relating to their satisfaction of these conditions. Despite doubts as to whether some of them had strictly met the conditions, the European Commission deemed them all eligible, and the euro was launched.2 The British government, though more clearly eligible than most other EU countries on the basis of the convergence criteria, decided to defer its decision on entry. In this paper we consider the arguments for and against Economic and Monetary Union, and in particular whether it would be in Britain's interest to join. We begin with a brief review of the state of the European economy and an analysis of the first year performance of the new Euro currency. [source] On the construction of maximum residual energy resource broadcast trees with minimum diameter in static ad hoc wireless networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 1 2006Chor Ping Low Abstract Each node in a wireless ad hoc network runs on a local energy source that has a limited energy life span. Thus, energy conservation is a critical issue in such networks. In addition, it is in general desirable to construct routes with low hop counts as a route with a high hop count is more likely to be unstable (because the probability that intermediate nodes will move away is higher). In this paper, we address these two issues concurrently with energy conservation as the primary objective and low hop count as the secondary objective. One way of addressing the energy conservation issue is to construct routes that maximize the minimum residual battery capacity available among all nodes in each route. A broadcast tree with all routes satisfying this condition is referred to as a maximum residual energy resource broadcast tree. A maximum residual energy resource broadcast tree with the least diameter is referred to as a minimum diameter maximum residual energy resource broadcast tree and the problem of constructing such a tree is referred to as the minimum diameter maximum residual energy resource broadcast routing problem (MDMRERBRP). We propose an algorithm for MDMRERBRP and prove that MDMRERBRP is optimally solvable in polynomial time using the proposed algorithm. Copyright © 2005 John Wiley & Sons, Ltd. [source] Understanding gay consumers' clothing involvement and fashion consciousnessINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 5 2007Ou Sha Abstract This study's primary objective was to provide a better understanding of gay consumers' clothing involvement and fashion consciousness. Personal in-depth interviews were conducted with 13 gay professionals in Canada. One hundred and forty-five usable survey questionnaires were also collected from gay consumers. The Fashion Involvement Index Scale (FII scale) was adapted for this study. Interview participants indicated that, in general, gay men tend to be more fashion conscious than heterosexual men. Survey results also indicated two dimensions, fashion interest and fashion awareness that were found to be stronger for this group of gay consumers than for heterosexual men. The FII value for the survey participants also resulted in a sum score mean value of 11.2, a medium level of fashion involvement that is a slightly higher level than has been found for heterosexual consumers. Interestingly, this study does not provide strong evidence of gay consumers' involvement in cutting-edge fashion trends. [source] Histoid leprosy: the impact of the entity on the postglobal leprosy elimination eraINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 6 2009FNASC, FRAS(LOND.), Virendra N. Sehgal MD A fresh focus on histoid leprosy is the primary objective of this article, especially in the context of the postglobal leprosy elimination era. The emergence of the entity following dapsone monotherapy is well recognized, in addition to de novo cases. Irregular and inadequate therapies, coupled with resistance to dapsone and/or mutant organisms, are responsible. It was considered to be worthwhile to take stock of the condition through its history, nomenclature, epidemiology, clinical characteristics, diagnosis, and differential diagnosis. The bacteriologic and histopathologic features and immunologic profile are also described. [source] Secularism as a Barrier to Integration?INTERNATIONAL MIGRATION, Issue 3 2004The French Dilemma ABSTRACT This article focuses on the secularism debate currently taking place in France by examining how this issue impacts the integration of immigrants, particularly Muslim immigrants. Secularism is one of the key values of French Republicanism, but one which has been challenged by the establishment of a settled population of Muslim immigrants in France. The issue has been particularly highlighted by the affaire des foulards (headscarf affair), an ongoing debate over the rights of Muslim girls to wear a headscarf to secular French schools. Discussions of the principle of secularism and of its application have been even more intense in recent months with the publication in December 2003 of a report by the Stasi Commission, a commission set up by President Chirac to investigate the application of the principle of secularism, and by the passage of legislation intended to outlaw the wearing of any "overt" religious insignia in French schools. This article examines these recent developments in the context of the long-running debate over Muslim women's right to wear a headscarf in French schools. It argues that the current focus on secularism provides evidence of the return of assimilation as a primary objective of public policy (Brubaker, 2001) and the decreasing strength of the movement in favour of the droit à la différence (right to difference). Finally, the paper argues that this has provided important obstacles to the integration of certain groups of immigrants, particularly Muslim immigrants. [source] Interscalene block using ultrasound guidance: impact of experience on resident performanceACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 10 2009S. L. OREBAUGH Background: We evaluated the weekly progress of anesthesiology residents performing an interscalene block with ultrasound guidance (UG) for block success rates and for the specific time intervals: (i) time to image the brachial plexus and (ii) time from insertion of the block needle until motor stimulation occurred. Our primary objective was to characterize the influence of experience over the course of the regional anesthesia rotation on the performance of a UG interscalene block by anesthesiology residents. Methods: Residents conducted an interscalene block with UG under the supervision of attending anesthesiologists experienced in this technique. Block efficacy, time intervals required to perform the block, and acute complications were recorded. We compared success rates over the course of the rotation, and analyzed process time data with respect to trainee level of experience, week of the trainee rotation, and patient body habitus. Results: Twenty-one trainees conducted 222 blocks over a consecutive 7-month period. Block success rate was 97.3%, and did not change significantly over the course of the 4-week rotation. Total block time and imaging time significantly decreased over the 4-week rotation, while the needle insertion-to-stimulation time did not change. Slower imaging time was predicted by obesity. Conclusion: The success rates for a UG interscalene block provided by supervised residents were initially high, and remained so throughout the 4-week rotation. Trainees required less time to image the nerves and to perform the block over the course of the rotation. [source] Effects of Low-Dose Prednisone on Bone Metabolism,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2005Francine N Ton MD Abstract Prednisone 5 mg/day suppresses multiple indices of bone formation in a randomized placebo-controlled trial in healthy postmenopausal females. This suggests that even low doses of prednisone may reduce bone repair or renewal and may have adverse effects on bone mass and/or bone strength. Introduction: High doses of chronic glucocorticoids are known to have adverse effects on bone, and measures to prevent bone loss are well established for doses >7.5 mg daily, because these doses can cause premature or exaggerated osteoporosis. However, it is unclear if chronic prednisone doses of 5 mg daily have the same effects on bone. There are no established recommendations for preventing glucocorticoid-induced osteoporosis in people taking prednisone 5 mg daily, a dose used frequently in medical practice to treat diseases of the lungs, joints, skin, muscles, eyes, nerves, etc. Our primary objective was to test whether prednisone 5 mg daily affects serum and urine indices of bone metabolism in healthy postmenopausal women. Our secondary objectives were to determine if prednisone 5 mg affected systolic or diastolic blood pressure or causes side effects. Materials and Methods: A double-blinded randomized placebo-controlled 8-week trial in 50 healthy postmenopausal women was conducted at the Massachusetts General Hospital Outpatient General Clinical Research Center. Patients were randomly assigned to prednisone 5 mg daily or matching placebo for 6 weeks, followed by a 2-week recovery phase. Markers of bone formation and resorption were determined at weeks 0, 2, 4, 6, and 8. Indices of osteoblast activity included serum propeptide of type I N-terminal procollagen (PINP), propeptide of type I C-terminal procollagen (PICP), osteocalcin, and bone-specific alkaline phosphatase (BSALP). Indices of osteoclast activity included urine and serum type I collagen N-telopeptide (NTX) and free urinary deoxypyridinoline (DPD). Results and Conclusions: Prednisone rapidly and significantly decreased serum PINP (p < 0.01), PICP (p < 0.01), and osteocalcin (p < 0.01) and free urinary deoxypyridinoline (p = 0.017). These changes were largely reversed during the recovery period. Side effects were indistinguishable in the two groups. Neither systolic nor diastolic blood pressure changed significantly throughout the study between the two groups. In conclusion, low-dose prednisone significantly decreases indices of bone formation and may decrease indices of bone resorption in postmenopausal women. Further studies are needed to assess the effects of low-dose prednisone on BMD and fracture risk. [source] Bilaminar techniques for the treatment of recession-type defects.JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 10 2003A comparative clinical study Abstract Objectives: Complete root coverage is the primary objective to be accomplished when treating gingival recessions in patients with aesthetic demands. Furthermore, in order to satisfy patient demands fully, root coverage should be accomplished by soft tissue, the thickness and colour of which should not be distinguishable from those of adjacent soft tissue. The aim of the present split-mouth study was to compare the treatment outcome of two surgical approaches of the bilaminar procedure in terms of (i) root coverage and (ii) aesthetic appearance of the surgically treated sites. Material and Methods: Fifteen young systemically and periodontally healthy subjects with two recession-type defects of similar depth affecting contralateral teeth in the aesthetic zone of the maxilla were enrolled in the study. All recessions fall into Miller class I or II. Randomization for test and control treatment was performed by coin toss immediately prior to surgery. All defects were treated with a bilaminar surgical technique: differences between test and control sites resided in the size, thickness and positioning of the connective tissue graft. The clinical re-evaluation was made 1 year after surgery. Results: The two bilaminar techniques resulted in a high percentage of root coverage (97.3% in the test and 94.7% in the control group) and complete root coverage (gingival margin at the cemento-enamel junction (CEJ)) (86.7% in the test and 80% in the control teeth), with no statistically significant difference between them. Conversely, better aesthetic outcome and post-operative course were indicated by the patients for test compared to control sites. Conclusions: The proposed modification of the bilaminar technique improved the aesthetic outcome. The reduced size and minimal thickness of connective tissue graft, together with its positioning apical to the CEJ, facilitated graft coverage by means of the coronally advanced flap. Zusammenfassung Hintergrund: Die vollständige Deckung der Wurzeloberfläche ist das primäre Ziel, das bei der Therapie von fazialen Rezessionen bei Patienten mit ästhetischen Ansprüchen erreicht werden soll. Weiterhin sollte die Rezessionsdeckung, wenn sie den Ansprüchen des Patienten vollends entsprechen soll, mit einer Dicke und Farbe der Gingiva erreicht werden, die nicht vom benachbarten Gewebe zu unterscheiden sind. Zielsetzung: Vergleich der Therapieergebnisse von 2 chirurgischen Varianten der zweischichtigen Technik im Halbseitenversuch hinsichtlich (1) Rezessionsdeckung und (2) ästhetischer Erscheinung der chirurgisch behandelten Stellen. Material und Methoden: 15 junge und parodontal gesunde Personen mit jeweils 2 Rezessionsdefekten ähnlicher Größe an kontralateralen Zähnen im ästhetischen Bereich des Oberkiefers wurden in die Studie aufgenommen. Alle Rezessionen gehörten in die Miller-Klassen I oder II. Die Randomisierung für die Test- und Kontrollbehandlung erfolgte unmittelbar präoperativ durch Münzwurf. Alle Defekte wurden nach einer zweischichtigen chirurgischen Technik behandelt: Die Unterschiede zwischen Test- und Kontrollstellen bestanden in Größe, Dicke und Positionierung des Bindegewebstransplantates. Die klinische Nachuntersuchung erfolgte 1 Jahr postoperativ. Ergebnisse: Beide zweischichtigen Techniken führten zu einem hohen Prozentsatz von Wurzeldeckung (Test: 97,3%; Kontrolle: 94,7%) und kompletter Wurzeldeckung (Gingivarand an der Schmelz-Zement-Grenze [SZG]) (Test: 86,7%; Kontrolle: 80%) ohne statistisch signifikante Unterschiede zwischen beiden Gruppen. Allerdings wurden mit der Testtherapie bessere ästhetische Ergebnisse erzielt als mit der Kontrollbehandlung. Schlussfolgerung: Die vorgestellte Modifikation der zweischichtigen Technik verbesserte die ästhetischen Ergebnisse. Die reduzierte Größe und minimale Dicke des Bindegewebstransplantates zusammen mit seiner Positionierung apikal der SZG erleichterten eine Deckung mittels eines koronalen Verschiebelappens. Résumé Objectif: Un recouvrement complet de la racine est le premier objectif lorsque l'on traite des récessions gingivales chez les patients ayant une demande esthétique. De plus, afin de satisfaire totalement la demande du patient, cette couverture radiculaire doit aussi être réalisé par des tissus mous de couleur et d'épaisseur qui ne se distinguent pas des tissus mous adjacents. Le but de cette étude en bouche séparée était de comparer le devenir de deux approches chirurgicales de la technique bilaminaire pour (i) le recouvrement de la racine et (ii) l'apparence esthétique des sites traités chirurgicalement. Matériel et Méthodes: 15 sujets jeunes et indemnes de maladie parodontale et systèmique présentant deux récessions de profondeur similaires sur des dents contralatérales dans des zones esthétiques du maxillaire furent enrollés dans cette étude. Toutes les récessions étaient des classes I ou II de Miller. La répartition pour les traitements test ou contrôle fut tirée à pile ou face juste avant la chirurgie. Toutes les lésions furent traitées par la technique bilaminaire, la différence entre les groupes résidant dans la taille, l'épaisseur et le positionnement du greffon de tissus conjonctif. La réévaluation clinique fut faite un an après la chirurgie. Résultats: Les deux techniques bilaminaires ont entrainé un fort pourcentage de recouvrement radiculaire (97.3% pour le groupe test et 94.7% pour le groupe contrôle) et le recouvrement complet (gencive marginale au niveau de la CEJ) (86.7% dans le groupe test et 80% pour le groupe contrôle) sans différence statistiquement significative entre elles. Par contre, un meilleur rendu esthétique et suites post opératoires furent rapportés par les patients pour le traitement test. Conclusions: La modification proposée de cette technique bilaminaire améliore le devenir esthétique. La taille réduite et l'épaisseur minimale greffon conjonctif et son positionnement apical au CEJ, ont facilité le recouvrement du greffon par le lambeau déplacé coronairement. [source] Multi-objective learning control for robotic manipulatorJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 10 2004Khin Kyu Kyu Win Several types of learning controllers have been proposed in the literature to improve the tracking performance of robot manipulators. In most cases, the learning algorithms emphasize mainly on a single objective of learning a desired motion of the end-effector. In some applications, more than one objective may be specified at the same time. For example, a robot may be required to follow a desired trajectory (primary objective) and at the same time avoid an obstacle (secondary objective). Thus, multi-objective learning control can be more effective to realize the collision-free tasks. In this paper, a multi-objective learning control problem is formulated and solved. In the proposed learning control system, the primary objective is to track a desired end-effector's motion and several secondary objectives can be specified for the desired orientation and for obstacles avoidance. To avoid obstacles in the workspace, a new learning concept called "region learning control" is also proposed in this paper. The proposed learning controllers do not require the exact knowledge of robot kinematics and dynamics. Sufficient condition is presented to guarantee the convergence of the learning system. The proposed learning controllers are applied to a four-link planar redundant manipulator and simulation results are presented to illustrate the performance. © 2004 Wiley Periodicals, Inc. [source] Cerebral blood flow and oxygen metabolism measured with the Kety,Schmidt method using nitrous oxideACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2009S. TAUDORF Background: The Kety,Schmidt method is the reference method for measuring global cerebral blood flow (CBF), cerebral metabolic rates (CMR) and flux, especially where scanners are unavailable or impractical. Our primary objective was to assess the repeatability of the Kety,Schmidt method in a variety of different approaches using inhaled nitrous oxide (N2O) as the tracer, combined with photoacoustic spectrometry. A secondary objective was to assess the impact of this tracer on the systemic vascular concentration of nitrite (NO2,). Methods: Twenty-nine healthy male volunteers underwent 61 CBF measurements by breathing a normoxic gas mixture containing 5% N2O until tension equilibrium. Paired blood samples were collected from an arterial and a jugular bulb catheter in the saturation or desaturation phase, by continuous or the discontinuous sampling. N2O concentration was measured with photoacoustic spectrometry after equilibration of blood samples with air. CBF was calculated by the Kety,Schmidt equation. CMR of oxygen (CMRO2) was determined by the Fick principle. NO2, in plasma and red blood cells (RBC) was measured by ozone-based chemiluminescence. Results: The most robust approach for CBF measurement was achieved by discontinuous sampling in the desaturation phase [CBF, 64 (95% confidence interval, 59,71 ml)] 100 g/min; CMRO2 1.8 (1.7,2.0) ,mol/g/min). The tracer did not influence plasma or RBC NO2, (P>0.05 vs. baseline). Conclusion: These findings confirm the reliability and robustness of the Kety,Schmidt method using inhaled N2O for the measurement of global CBF and CMR. At the low tracer concentration used, altered NO metabolism is unlikely to have affected cerebral haemodynamic function. [source] Application of a digital technique in evaluating the reliability of shade guidesJOURNAL OF ORAL REHABILITATION, Issue 5 2004E. Cal summary, There appears to be a need for a reliable method for quantification of tooth colour and analysis of shade. Therefore, the primary objective of this study was to show the applicability of graphic software in colour analysis and secondly to investigate the reliability of commercial shade guides produced by the same manufacturer, using this digital technique. After confirming the reliability and reproducibility of the digital method by using self-assessed coloured images, three shade guides of the same manufacturer were photographed in daylight and in studio environments with a digital camera and saved in tagged image file format (TIFF) format. Colour analysis of each photograph was performed using the Adobe Photoshop 4·0 graphic program. Luminosity, and red, green, blue (L and RGB) values of each shade tab of each shade guide were measured and the data were subjected to statistical analysis using the repeated measure Anova test. The L and RGB values of the images taken in daylight differed significantly from those of the images taken in studio environment (P < 0·05). In both environments, the luminosity and red values of the shade tabs were significantly different from each other (P < 0·05). It was concluded that, when the environmental conditions were kept constant, the Adobe Photoshop 4·0 colour analysis program could be used to analyse the colour of images. On the other hand, the results revealed that the accuracy of shade tabs widely being used in colour matching should be readdressed. [source] Technology, security, and individual privacy: New tools, new threats, and new public perceptionsJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 3 2005Lee S. Strickland Highly portable information collection and transmission technologies such as radio frequency identification (RFID) tags and smart cards are becoming ubiquitous in government and business,employed in functions including homeland security, information security, physical premises security, and even the control of goods in commerce. And, directly or indirectly, in many of these applications, it is individuals and their activities that are tracked. Yet, a significant unknown is (a) whether the public understands these technologies and the manner in which personally identifiable information may be collected, maintained, used, and disseminated; and (b) whether the public consents to these information practices. To answer these and related questions, we surveyed a select group of citizens on the uses of this technology for business as well as homeland security purposes. We found a significant lack of understanding, a significant level of distrust even in the context of homeland security applications, and a very significant consensus for governmental regulation. We conclude that a primary objective for any organization deploying these technologies is the promulgation of a comprehensive Technology Privacy Policy, and we provide detailed specifications for such an effort. [source] Noninferiority and equivalence designs: Issues and implications for mental health researchJOURNAL OF TRAUMATIC STRESS, Issue 5 2008Carolyn J. Greene The terms noninferiority and equivalence are often used interchangeably to refer to trials in which the primary objective is to show that a novel intervention is as effective as the standard intervention. The use of these designs is becoming increasingly relevant to mental health research. Despite the fundamental importance of these designs, they are often poorly understood, improperly applied, and subsequently misinterpreted. In this article, the authors explain noninferiority and equivalence designs and key methodological and statistical considerations. Decision points in using these designs are discussed, such as choice of control condition, determination of the noninferiority margin, and calculation of sample size and power. With increasing utilization of these designs, it is critical that researchers understand the methodological issues, advantages, disadvantages, and related challenges. [source] The Ediacaran Period: a new addition to the geologic time scaleLETHAIA, Issue 1 2006ANDREW KNOLL The International Union of Geological Sciences has approved a new addition to the geologic time scale: the Ediacaran Period. The Ediacaran is the first Proterozoic period to be recognized on the basis of chronostratigraphic criteria and the first internationally ratified, chronostratigraphically defined period of any age to be introduced in more than a century. In accordance with procedures established by the International Commission on Stratigraphy, the base of the Ediacaran Period is defined by a Global Stratotype Section and Point (GSSP) placed at the base of the Nuccaleena Formation cap carbonate directly above glacial diamictites and associated facies at Enorama Creek in the Flinders Ranges of South Australia. Its top is defined by the initial GSSP of the Cambrian Period. The new Ediacaran Period encompasses a distinctive interval of Earth history that is bounded both above and below by equally distinctive intervals. Both chemostratigraphic and biostratigraphic data indicate that the subdivision of the period into two or more series is feasible, and this should be a primary objective of continuing work by the Ediacaran Subcommission of the ICS. [source] Spectrum of Fibrosing Diffuse Parenchymal Lung DiseaseMOUNT SINAI JOURNAL OF MEDICINE: A JOURNAL OF PERSONALIZED AND TRANSLATIONAL MEDICINE, Issue 1 2009Adam S. Morgenthau MD Abstract The interstitial lung diseases are a heterogeneous group of disorders characterized by inflammation and/or fibrosis of the pulmonary interstitium. In 2002, the American Thoracic Society and the European Respiratory Society revised the classification of interstitial lung diseases and introduced the term diffuse parenchymal lung disease. The idiopathic interstitial pneumonias are a subtype of diffuse parenchymal lung disease. The idiopathic interstitial pneumonias are subdivided into usual interstitial pneumonia (with its clinical counterpart idiopathic interstitial pneumonia), nonspecific interstitial pneumonia, cryptogenic organizing pneumonia, acute interstitial pneumonia, desquamative interstitial pneumonia, respiratory bronchiolitis interstitial lung disease, and lymphocytic pneumonia. Sarcoidosis and hypersensitivity pneumonitis are the 2 most common granulomatous diffuse parenchymal lung diseases. Rheumatoid arthritis, systemic sclerosis, and dermatomyositis/polymyositis (causing antisynthetase syndrome) are diffuse parenchymal lung diseases of known association because these conditions are associated with connective tissue disease. Hermansky-Pudlak syndrome is a rare genetic diffuse parenchymal lung disease characterized by the clinical triad of pulmonary disease, oculocutaneous albinism, and bleeding diathesis. This review provides an overview of the chronic fibrosing diffuse parenchymal lung diseases. Its primary objective is to illuminate the clinical challenges encountered by clinicians who manage the diffuse parenchymal lung diseases regularly and to offer potential solutions to those challenges. Treatment for the diffuse parenchymal lung diseases is limited, and for many patients with end-stage disease, lung transplantation remains the best option. Although much has been learned about the diffuse parenchymal lung diseases during the past decade, research in these diseases is urgently needed. Mt Sinai J Med 76:2,23, © 2009 Mount Sinai School of Medicine [source] Soil vapor extraction system design: A case study comparing vacuum and pore-gas velocity cutoff criteriaREMEDIATION, Issue 1 2006Kenneth L. Dixon Soil vapor extraction (SVE) systems are typically designed based on the results of a vadose-zone pumping test (transient or steady-state) using a pressure criterion to establish the zone of influence (ZOI). A common problem associated with pressure-based SVE design is overestimating the ZOI of the extraction well. As a result, design strategies based upon critical pore- gas velocity (CPGV) have become more common. Field tests were conducted at the Savannah River Site (SRS) to determine the influence of a vapor extraction well based upon both a pressure and pore- gas velocity design criterion. The results from these tests show that an SVE system designed based upon a CPGV is more robust and will have shorter cleanup times due to increased flow throughout the treatment zone. Pressure-based SVE design may be appropriate in applications where soil gas containment is the primary objective; however, in cases where the capture and removal of contaminated soil gas is the primary objective, CPGV is a better design criterion. © 2006 Wiley Periodicals, Inc. [source] Robust estimation of the optimal hedge ratioTHE JOURNAL OF FUTURES MARKETS, Issue 8 2003Richard D. F. Harris When using derivative instruments such as futures to hedge a portfolio of risky assets, the primary objective is to estimate the optimal hedge ratio (OHR). When agents have mean-variance utility and the futures price follows a martingale, the OHR is equivalent to the minimum variance hedge ratio,which can be estimated by regressing the spot market return on the futures market return using ordinary least squares. To accommodate time-varying volatility in asset returns, estimators based on rolling windows, GARCH, or EWMA models are commonly employed. However, all of these approaches are based on the sample variance and covariance estimators of returns, which, while consistent irrespective of the underlying distribution of the data, are not in general efficient. In particular, when the distribution of the data is leptokurtic, as is commonly found for short horizon asset returns, these estimators will attach too much weight to extreme observations. This article proposes an alternative to the standard approach to the estimation of the OHR that is robust to the leptokurtosis of returns. We use the robust OHR to construct a dynamic hedging strategy for daily returns on the FTSE100 index using index futures. We estimate the robust OHR using both the rolling window approach and the EWMA approach, and compare our results to those based on the standard rolling window and EWMA estimators. It is shown that the robust OHR yields a hedged portfolio variance that is marginally lower than that based on the standard estimator. Moreover, the variance of the robust OHR is as much as 70% lower than the variance of the standard OHR, substantially reducing the transaction costs that are associated with dynamic hedging strategies. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:799,816, 2003 [source] Combination Nonviral Interleukin-2 Gene Immunotherapy For Head and Neck Cancer: From Bench Top to BedsideTHE LARYNGOSCOPE, Issue 3 2005Bert W. O'Malley Jr MD Abstract Objective/Hypothesis: Intralesional delivery of cytokine genes has emerged as a promising therapeutic strategy for the treatment of cancer. In addition to the therapeutic effect of the delivered cytokine gene, the components of the gene delivery system also have been shown to induce beneficial immune responses. On the basis of these principles, we hypothesized that a molecular therapy could be developed that would provide synergistic antitumor activity by way of intralesional expression of interleukin (IL)-2 from a recombinant plasmid combined with induction of endogenous interferon (IFN)-, and IL-12 cytokines by immunostimulatory DNA. Our objective in these studies was to create and optimize a novel formulation of cationic lipid and DNA that generates local production of IL-2 protein within a targeted tumor environment with concomitant induction of the antitumor cytokines IFN-, and IL-12. Study Design: Prospective laboratory drug development plan that would produce human clinical trials. Materials and Methods: Engineered bacterial plasmids containing a cytomegalovirus promoter (CMV)-IL-2 expression cassette were specifically formulated with cationic lipids and optimized for antitumor effect in a floor of mouth murine tumor model. The treated tumors were assayed for local expression of IL-2 and concurrent expression of secondary cytokines IFN-, and IL-12. Established tumors in C3H/HeJ mice were treated with various IL-2 gene formulations, and clinical and immunologic responses were evaluated. Immunologic studies were performed and included cytolytic T-cell assays and cytokine expression profiles. For human clinical trials, a phase I 10 patient formulated IL-2 gene therapy study was completed. Subsequently, two large scale, phase II multi-institutional and multi-international studies were initiated comparing non-viral IL-2 gene therapy to palliative methotrexate chemotherapy or in combination with cisplatin. Results: In the preclinical stage, maximum tumor inhibition in animal models was obtained using IL-2 plasmid formulated with 1,2-dioleyloxypropyl-3-trimethyl ammonium chloride (DOTMA):cholesterol (1:1 mol:mol) at a plasmid:lipid charge ratio of 1:0.5 (,/+). Cationic lipid formulated IL-2 plasmid significantly inhibited tumor growth compared with formulated control plasmid (P < .01) or vehicle (lactose; P < .01). Consistent with previously reported studies of the immunostimulatory activity of DNA of bacterial origin, treatment of tumors with control plasmid in cationic lipid formulation induced production of endogenous IFN-, and IL-12 but not IL-2. Treatment of tumors with formulated IL-2 plasmid produced IL-2 protein levels that were 5-fold over background and increased IFN-, by 32-fold (P < .001) and IL-12 by 5.5-fold (P < .001) compared with control plasmid formulations. The phase I human trial demonstrated dose escalation safety, which was its primary objective, and there was one anecdotal reduction in tumor size. The phase II studies have been initiated and focus on either comparing the novel nonviral IL-2 gene immunotherapy formulation alone to methotrexate or comparing IL-2 gene therapy in combination with cisplatin in recurrent or unresectable patients with head and neck squamous cell carcinoma. Conclusions: The preclinical data provided proof of principle for matching a delivered IL-2 transgene with an immunostimulatory nonviral formulation to enhance intralesional production of therapeutic cytokines for the maximization of antitumor response. Human clinical trials have demonstrated this novel therapy to be safe in the human clinical setting. Phase II trials have been initiated to assess efficacy and feasibility as a single or combination therapy for head and neck cancer. [source] Screening and Brief Intervention to Reduce Marijuana Use Among Youth and Young Adults in a Pediatric Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 11 2009Edward Bernstein MD Abstract Objectives:, Marijuana was involved in 209,563 emergency department (ED) visits in 2006, according to the Drug Abuse Warning Network. Although screening and brief intervention (SBI) has been effective in changing drinking among ED patients in a number of studies, tests of marijuana SBI in a pediatric emergency department (PED) have not yet been reported. The aim of this pilot study was to test whether SBI is effective in reducing marijuana consumption among youth and young adults presenting to a PED with a diverse range of clinical entities. Methods:, A three-group randomized controlled preliminary trial was structured to test 1) differences between Intervention (Int) and standard Assessed Control (AC) groups in marijuana consumption, from baseline to 12 months, and 2) the feasibility of adding a Nonassessed Control (NAC) group to evaluate regression to the mean and assessment reactivity. Patients aged 14,21 years in an urban, academic PED were screened during 2006,2007, using standardized risk factor questions. Subjects were eligible if they used marijuana three or more times in the past 30 days, but were excluded for co-occurring high-risk alcohol use. Consented enrollees were randomized to NAC, AC, and Int groups in a two-stage process that permitted blinding to status during assessment and follow-up. NACs received a resource handout, written advice about marijuana use risks, and a 12-month follow-up appointment. ACs were assessed using standardized instruments and received resources, written advice, and 3- and 12-month follow-up appointments. The Int group received assessment, resources, written advice, 3- and 12-month appointments, a 20-minute structured conversation conducted by older peers, and a 10-day booster telephone call. A peer educator utilized a motivational style interview protocol adapted for adolescents to elicit daily life context and future goals, provide feedback, review pros and cons of marijuana use, assess readiness to change, evaluate strengths and assets, negotiate a contract for change, and make referrals to treatment and/or other resources. Measurements included demographic information; 30-day self-report of marijuana use; attempts to quit, cut back, or change conditions of use; and risk factor questions repeated at follow-up. Results:, Among 7,804 PED patients screened, 325 were eligible; 210 consented and enrolled (Int, n = 68; AC, n = 71; NAC, n = 71), with a 12-month follow-up rate of 71%. For the primary objective, we compared Int to AC. At 12 months, Int participants were more likely to be abstinent for the past 30 days than ACs (odds ratio [OR] for reported abstinence = 2.89, 95% confidence interval [CI] = 1.22 to 6.84, p < 0.014). The Int group had greater reduction in days used, baseline to 12 months, controlling for baseline (Int = ,7.1 vs. AC = ,1.8), were less likely to have been high among those who smoked (OR = 0.39, 95% CI = 0.17 to 0.89, p < 0.05), and were more likely to receive referrals. In a linear regression model controlling for baseline use, NACs smoked 4 fewer days per month than ACs, but consumption was not significantly different, suggesting no assessment reactivity effect. Conclusions:, A preliminary trial of SBI promoted marijuana abstinence and reduced consumption among PED patients aged 14,21 years. A no-contact condition for the NAC group over the year after enrollment was insufficient to capture enrollees for follow-up across a range of baseline acuity. [source] Managing precipitation use in sustainable dryland agroecosystemsANNALS OF APPLIED BIOLOGY, Issue 2 2004GARY A PETERSON Summary In the Great Plains of North America potential evaporation exceeds precipitation during most months of the year. About 75% of the annual precipitation is received from April through September, and is accompanied by high temperatures and low relative humidity. Dryland agriculture in the Great Plains has depended on wheat production in a wheat-fallow agroecosystem (one crop year followed by a fallow year). Historically this system has used mechanical weed control practices during the fallow period, which leaves essentially no crop residue cover for protection against soil erosion and greatly accelerates soil organic carbon oxidation. This paper reviews the progress made in precipitation management in the North American Great Plains and synthesises data from an existing long-term experiment to demonstrate the management principles involved. The long-term experiment was established in 1985 to identify dryland crop and soil management systems that would maximize precipitation use efficiency (maximization of biomass production per unit of precipitation received), improve soil productivity, and increase economic return to the farmers in the West Central portion of the Great Plains. Embedded within the primary objective are sub-objectives that focus on reducing the amount of summer fallow time and reversing the soil degradation that has occurred in the wheat-fallow cropping system. The experiment consists of four variables: 1) Climate regime; 2) Soils; 3) Management systems; and 4) Time. The climate variable is based on three levels of potential evapotranspiration (ET), which are represented by three sites in eastern Colorado. All sites have annual long-term precipitation averages of approximately 400,450 mm, but vary in growing season open pan evaporation from 1600 mm in the north to 1975 mm in the south. The soil variable is represented by a catenary sequence of soils at each site. Management systems, the third variable, differ in the amount of summer fallow time and emphasize increased crop diversity. All systems are managed with no-till techniques. The fourth variable is time, and the results presented in this paper are for the first 12 yr (3 cycles of the 4-yr system). Comparing yields of cropping systems that differ in cycle length and systems that contain fallow periods, when no crop is produced, is done with a technique called "annualisation". Yields are "annualised" by summing yields for all crops in the system and dividing by the total number of years in the system cycle. For example in a wheat-fallow system the wheat yield is divided by two because it takes 2 yr to produce one crop. Cropping system intensification increased annualised grain and crop residue yields by 75 to 100% compared to wheat-fallow. Net return to farmers increased by 25% to 45% compared to wheat-fallow. Intensified cropping systems increased soil organic C content by 875 and 1400 kg ha,1, respectively, after 12 yr compared to the wheat-fallow system. All cropping system effects were independent of climate and soil gradients, meaning that the potential for C sequestration exists in all combinations of climates and soils. Soil C gains were directly correlated to the amount of crop residue C returned to the soil. Improved macroaggregation was also associated with increases in the C content of the aggregates. Soil bulk density was reduced by 0.01g cm,3 for each 1000 kg ha,1 of residue addition over the 12-yr period, and each 1000 kg ha,1 of residue addition increased effective porosity by 0.3%. No-till practices have made it possible to increase cropping intensification beyond the traditional wheat-fallow system and in turn water-use efficiency has increased by 30% in West Central Great Plains agroecosystems. Cropping intensification has also provided positive feedbacks to soil productivity via the increased amounts of crop residue being returned to the soil. [source] | |||||||||||||||||||||||||||||||||||||