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Mixed
Kinds of Mixed Terms modified by Mixed Selected AbstractsRESERVOIR POTENTIAL OF A LACUSTRINE MIXED CARBONATE / SILICICLASTIC GAS RESERVOIR: THE LOWER TRIASSIC ROGENSTEIN IN THE NETHERLANDSJOURNAL OF PETROLEUM GEOLOGY, Issue 1 2008D. Palermo The Lower Triassic Rogenstein Member of the Buntsandstein Formation produces gas at the De Wijk and Wanneperveen fields, NE Netherlands and consists mainly of claystones with intercalated oolitic limestone beds. The excellent reservoir properties of the oolites (,= 20-30%; k = 5-4000 mD) are predominantly controlled by depositional facies. Oolitic limestones are interpreted as the storm and wave deposits of a shallow, desert lake located in the Central European Buntsandstein Basin. The vertical sequence of lithofacies in the Rogenstein Member indicates cyclic changes of relative lake level. The reservoir rock is vertically arranged in a three-fold hierarchy of cycles, recognised both in cores and wireline logs. These cycles are a key to understanding the distribution of reservoir facies, and are used as the basis for a high-resolution sequence stratigraphic correlation of the reservoir units. Slight regional-scale thickness variations of the Rogenstein Member (in the order of tens of metres) are interpreted as the effects of differential subsidence associated with the inherited Palaeozoic structural framework. The depositional basin can be subdivided into subtle palaeo-highs and -lows which controlled facies distribution during Rogenstein deposition. Oolitic limestones show their greatest lateral extent and thickest development in the Middle Rogenstein during large-scale maximum flooding. Potential reservoir rocks (decimetre to metres thick) are present in the NE Netherlands, in particular in the Lauwerszee Trough and the Lower Saxony Basin, where abundant gas shows of 200 - 4000 ppm CH4 have been recorded. Preserved primary porosity is interpreted to be a result of rapid burial in subtle depositional palaeo-lows in this area. The thickest, amalgamated oolite intervals (tens of metres thick) occur in the eastern part of the Central Netherlands Basin. Because of poor reservoir properties, other areas appear to be less promising in terms of Rogenstein exploration potential. [source] A double-blind, placebo-controlled pilot study of quetiapine for depressed adolescents with bipolar disorderBIPOLAR DISORDERS, Issue 5 2009Melissa P DelBello Objective:, To conduct a pilot study comparing the effects of quetiapine and placebo for the treatment of depressive episodes in adolescents with bipolar I disorder. Method:, Thirty-two adolescents (ages 12,18 years) with a depressive episode associated with bipolar I disorder were randomized to eight weeks of double-blind treatment with quetiapine, 300,600 mg/day, or placebo. This two-site study was conducted from March 2006 through August 2007. The primary efficacy measure was change in Children's Depression Rating Scale,Revised Version (CDRS-R) scores from baseline to endpoint. Secondary efficacy measures included change in CDRS-R scores over the eight-week study period (PROC MIXED), changes from baseline to endpoint in Hamilton Anxiety Rating Scale (HAM-A), Young Mania Rating Scale (YMRS), and Clinical Global Impression,Bipolar Version Severity (CGI-BP-S) scores, as well as response and remission rates. Safety and tolerability were assessed weekly. Results:, There was no statistically significant treatment group difference in change in CDRS-R scores from baseline to endpoint (p = 0.89, effect size =,0.05, 95% confidence interval: ,0.77,0.68), nor in the average rate of change over the eight weeks of the study (p = 0.95). Additionally, there were no statistically significant differences in response (placebo =67% versus quetiapine = 71%) or remission (placebo = 40% versus quetiapine = 35%) rates, or change in HAM-A, YMRS, or CGI-BP-S scores (all p > 0.7) between treatment groups. Dizziness was more commonly reported in the quetiapine (41%) than in the placebo (7%) group (Fisher's exact test, p = 0.04). Conclusions:, The results suggest that quetiapine monotherapy is no more effective than placebo for the treatment of depression in adolescents with bipolar disorder. However, limitations of the study, including the high placebo response rate, may have contributed to our findings and should be considered in the design of future investigations of pharmacological interventions for this population. [source] The Role of Natriuretic Peptides in Patients With Chronic Complex (Mixed or Multiple) Heart Valve DiseaseCONGESTIVE HEART FAILURE, Issue 2 2010FRACP, Naylin Bissessor MBChB N-terminal prohormone B-type natriuretic peptide (NT-proBNP) is an important biomarker of prognosis in heart failure and single valve disease. There are limited studies of complex valve disease. Patients with complex valve disease adopt a sedentary lifestyle, so symptoms may be difficult to detect. The authors aimed to determine whether NT-proBNP correlates with the severity of the valve lesion and underlying cardiac function and whether resting NT-proBNP predicts impaired peak VO2 in patients with complex valve disease. Forty-five patients with complex moderate to severe stenosis or regurgitation of the heart valves underwent a clinical assessment, echocardiography, resting NT-proBNP assessment, and formal cardiopulmonary exercise testing. In a multivariate analysis, the log NT-proBNP (,=,9.3, SE=1.9, P<.0001) and lean body weight (,=0.59, SE=0.22, P=.01) were dominant independent predictors of peak VO2. An NT-proBNP value of 84 pmol/L had 77% sensitivity and 70% specificity to predict impaired functional capacity, peak VO2 <60% (predicted), area under the curve=0.80. Resting NT-proBNP was the best predictor of peak VO2 in patients with complex valve disease, while symptoms and ejection fraction are a less reliable guide. Congest Heart Fail. 2010;16:50,54. © 2009 Wiley Periodicals, Inc. [source] Synthesis, Characterization and OFET Properties of Amphiphilic Mixed (Phthalocyaninato)(porphyrinato)europium(III) ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 7 2009Pan Ma Abstract Amphiphilic mixed (phthalocyaninato)(porphyrinato)europium(III) triple-decker complexes Eu2[Pc(15C5)4]2[T(C10H21)4P] (1) and Eu2[Pc(15C5)4]2[TPOPP] (2) [H2Pc(15C5)4 = 2,3,9,10,16,17,23,24-tetrakis(15-crown-5)phthalocyanine; H2T(C10H21)4P = meso -5,10,15,20-tetra- n -decylporphyrin, H2TPOPP = meso -5,10,15,20-tetrakis(4-pentyloxyphenyl)porphyrin] were designed and synthesized by the raise-by-one-story method. These novel sandwich triple-decker complexes were characterized by a wide range of spectroscopic methods, and they were also electrochemically studied. Highly ordered films were fabricated by the Langmuir,Blodgett (LB) technique into organic field-effect transistors (OFETs). The devices display good OFET performance with a carrier mobility in the range 0.03,0.78 cm2,V,1,s,1. As expected, the devices show a low threshold voltage range from ,1.19 to ,4.34 V. The mobility of compound 1 reaches 0.78 cm2,V,1,s,1, which is the highest value so far achieved for LB film-based OFETs, as a result of the narrow energy gap (1.04 eV) of this compound.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Mixed (composite) glandular-endocrine cell carcinoma of the gallbladderHPB, Issue 1 2001N Yannakou Background A mixed pattern of glandular and neuroendocrine elements is rare in tumours at any site within the gastrointestinal tract but particularly so in the gallbladder. Case outline A 72-year-old woman presented with abdominal pain and jaundice and was found to have a large mass in the fundus of the gallbladder. The mass was radically excised to include a wedge of liver and the hepatoduodenal lymph nodes. Histopathological examination of the resected gallbladder showed an invasive tumour composed of both adenocarcinoma and endocrine cell carcinoma, with apparent transitions between them. The patient received no further treatment and died two months later. Discussion There are 14 previous case reports of mixed adeno/endocrine carcinoma of the gallbladder. Histochemical similarities between the two neoplastic components of the present tumour would support their origin from a common precursor cell, but the alternative hypothesis of coincidental neoplastic change in two different cell types cannot be excluded. [source] Mixed ,2/,, nonlinear filteringINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 4 2009M. D. S. Aliyu Abstract In this paper, we consider the mixed ,2/,, filtering problem for affine nonlinear systems. Sufficient conditions for the solvability of this problem with a finite-dimensional filter are given in terms of a pair of coupled Hamilton,Jacobi,Isaacs equations (HJIEs). For linear systems, it is shown that these conditions reduce to a pair of coupled Riccati equations similar to the ones for the control case. Both the finite-horizon and the infinite-horizon problems are discussed. Simulation results are presented to show the usefulness of the scheme, and the results are generalized to include other classes of nonlinear systems. Copyright © 2008 John Wiley & Sons, Ltd. [source] Modeling of air separation in a LSCF hollow-fiber membrane moduleAICHE JOURNAL, Issue 7 2002Xiaoyao Tan Mixed ion-conducting ceramic membranes are promising in oxygen separation from air due to their infinite permselectivity. Hollow-fiber-shaped membranes can provide a high surface area for such an application. A mathematical model for a hollow-fiber La0.6Sr0.4Co0.2F0.8O3,,(LSCF) membrane module for air separation was developed and a performance of the module at various operating conditions was studied theoretically. The simulation results reveal that the cocurrent is a better operating flow pattern than the countercurrent flow pattern. The vacuum operation on the lumen side of the membrane module is preferable to the elevated pressure operation on the shell side for achieving high oxygen productivity. A high vacuum level and a desired membrane area are essential to produce the pure oxygen and nitrogen simultaneously. Experimental results and kinetic parameters in the literature obtained from the LSCF membrane for air separation agreed satisfactorily with the theoretical solutions. [source] WATER QUALITY IN AGRICULTURAL, URBAN, AND MIXED LAND USE WATERSHEDS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2004Chris B. Coulter ABSTRACT: Water quality and nonpoint source (NPS) pollution are important issues in many areas of the world, including the Inner Bluegrass Region of Kentucky where urban development is changing formerly rural watersheds into urban and mixed use watersheds. In watersheds where land use is mixed, the relative contributions of NPS pollution from rural and urban land uses can be difficult to separate. To better understand NPS pollution sources in mixed use watersheds, surface water samples were taken at three sites that varied in land use to examine the effect of land use on water quality. Within the group of three watersheds, one was predominately agriculture (Agricultural), one was predominately urban (Urban), and a third had relatively equal representation of both types of land uses (Mixed). Nitrogen (N), phosphorus (P), total suspended solids (TSS), turbidity, pH, temperature, and streamflow were measured for one year. Comparisons are made among watersheds for concentration and fluxes of water quality parameters. Nitrate and orthophosphate concentrations were found to be significantly higher in the Agricultural watershed. Total suspended solids, turbidity, temperature, and pH, were found to be generally higher in the Urban and Mixed watersheds. No differences were found for streamflow (per unit area), total phosphorus, and ammonium concentrations among watersheds. Fluxes of orthophosphate were greater in the Agricultural watershed that in the Urban watershed while fluxes of TSS were greater in the Mixed watershed when compared to the Agricultural watershed. Fluxes of nitrate, ammonium, and total phosphorus did not vary among watersheds. It is apparent from the data that Agricultural land uses are generally a greater source of nutrients than the Urban land uses while Urban land uses are generally a greater source of suspended sediment. [source] In vitro effects of phlorotannins from Ascophyllum nodosum (brown seaweed) on rumen bacterial populations and fermentationJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2009Yuxi Wang Abstract BACKGROUND: Use of brown algae (seaweed) in ruminant diets is increasing, but the effects of its phlorotannins (PT) on rumen microbial ecology have not been determined. Mixed forage (50:25:25 ground barley silage,alfalfa hay,grass hay) was used as substrate in a batch culture ruminal incubation that included PT extracted from Ascophyllum nodosum, with and without polyethylene glycol. Principal ruminal bacteria were quantified using real-time polymerase chain reaction. RESULTS: At 500 µg mL,1, PT reduced growth of Fibrobacter succinogenes by 78%, 83% and 65% at 6, 12 and 24 h (P < 0.001), Ruminococcus albus at 24 h only (P < 0.01) and did not affect R. flavefaciens. Non-cellulolytic bacteria Selenomonas ruminantium, Ruminobacter amylophilus and Prevotella bryantii were increased (P < 0.001) by PT at 12 and 24 h. Effects of PT on fermentation products (gas production, volatile fatty acid profiles and ammonia accumulation) were consistent with alterations in rumen microbial populations. CONCLUSION: The effects of PT on ruminal bacteria were species-dependent, which suggests that diet may mediate PT effects on animal performance. The variation in sensitivity of ruminal bacteria to PT reflects previously reported effects of condensed tannins from terrestrial plants on microbial populations. Copyright © 2009 Crown in the right of Canada. Published by John Wiley & Sons, Ltd [source] Improvement of Mechanical Properties of Self Setting Calcium Phosphate Bone Cements Mixed With Different Metal OxidesMATERIALWISSENSCHAFT UND WERKSTOFFTECHNIK, Issue 12 2003U. Gbureck Calciumphosphat Zemente; Metalloxide; Mechanische Eigenschaften Abstract Calcium phosphate cements (CPC), based on multicomponent powder mixtures of calcium orthophosphates with medium particle sizes in the region of 1 - 20 ,m, set isothermally in an aqueous environment to form hydroxyapatite (HA). HA cement reactants include tetracalcium phosphate (TTCP), tricalcium phosphate (TCP), dicalcium phosphate anhydrate (DCPA), dicalcium phosphate dihydrate (DCPD), monocalcium phosphate (MCPA) or octacalcium phosphate (OCP). The aim of this study was to improve the mechanical performance of TTCP / DCPA cement by adding several metal oxides to tetracalcium phosphate during the fabrication process. Cements based on tetracalcium phosphate mixed with silica or titanium oxide showed significant increases in compressive strength, approximately 80 - 100 MPa, whilst no change in the mechanical behavior of CPC was observed if zirconia was added. X-ray diffraction measurement confirmed the setting reaction of doped cements was similar to that of pure CPC. Low crystalline HA was found to be the main constituant of set cement; additional phases, such as calcium titanate or calcium zirconate, were not involved in the reaction. A mechanical reinforcement effect was thought to result from changes in the thermodynamic or kinetic solubilities of doped tetracalcium phosphates, this would lead to slower HA crystal formation and a more cross-linked cement structure. Verbesserung der mechanischen Eigenschaften von Calciumphosphat-Zementen durch Modifikation mit verschiedenen Metalloxiden Calciumphosphat-Zemente, CPC, bestehen aus Pulvermischungen verschiedener Calcium orthophophate, beispielsweise Tetracalciumphosphat (TTCP), Tricalciumphosphat (TCP), Dicalciumphosphatanhydrid (DCPA), Dicalciumphosphatdihydrat (DCPD), Monocalcium phosphatanhydrid (MCPA) oder Octacalciumphosphat (OCP) mit durchschnittlichen Partikelgrößen im Bereich von 1 , 20 ,m. Die Zemente binden in wässriger Umgebung isotherm zu Hydroxylapatit ab. Das Ziel dieser Arbeit war die Verbesserung materialspezifischer Eigenschaften , wie die mechanische Festigkeit - eines TTCP / DCPA-Zementes durch die Verwendung von Metalloxiden im Syntheseprozess von Tetracalciumphosphat. Zemente, die aus mit Silicium- oder Titandioxid versetzten Tetracalciumphosphaten hergestellt wurden, zeigten eine deutliche Steigerung der Druckfestigkeit auf Werte von 80 , 100 MPa, während im Falle von Zirkoniumdioxid keine Änderung der mechanischen Stabilität erreicht werden konnte. Röntgendiffraktometrische Untersuchungen ergaben, dass die Abbindereaktion dieser Zemente ähnlich der eines reinen TTCP / DCPA-Zements verläuft. Jeweiliges Hauptprodukt war niedrigkristalliner Hydroxylapatit, die im Herstellungsprozess von Tetracalciumphosphat entstandenen Nebenprodukte Calciumtitanat bzw. ,zirkonat waren nicht an der Abbindereaktion beteiligt. Ein Grund für die Steigerung der mechanischen Stabilität ist offensichtlich die Veränderung der kinetischen und thermodynamischen Löslichkeit der synthetisierten Tetracalciumphosphate, die zu einer langsameren Abbindereaktion und somit einer besseren Vernetzung in der Hydroxylapatitstruktur führt. [source] Detonation and Blast Wave Characteristics of Nitromethane Mixed with Particles of an Aluminium,Magnesium AlloyPROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 2 2010Waldemar Abstract Investigation of detonation parameters, blast wave characteristics and quasi-static pressures (QSPs) for the mixtures of nitromethane and particles of an aluminium and magnesium (Al3Mg4) alloy was carried out. The mixtures of gelled nitromethane containing 15,60,wt.-% AlMg alloy were tested. Detonation velocity and Gurney energy were determined. Parameters of blast waves produced by charges of the investigated explosives were measured. QSP measurements were conducted in a steel chamber of 0.15,m3 volume filled with air. Thermochemical and gasdynamical calculations were also performed. The degree of combustion of the metallic addition with the gaseous products during detonation and expansion is discussed. [source] Structural and Functional Features of Choroid Epithelium from Buffalo BrainTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 11 2007Gaetano Scala Abstract Choroid plexuses (CPs) play pivotal roles in many processes that establish, survey, and maintain the biochemical and cellular status of the central nervous system (CNS). Changes in the anatomy and physiology of CPs have been linked to several CNS diseases. However, CP structure and function are not definitely known. Here, we report structural and functional features of choroid epithelium from buffalo brain never described before. Mixed with common epithelial cells, two novel cell types were identified by scanning and transmission electron microscopies. The first peculiar cells showed a globular apical portion projecting into the ventricular cavities, and a basal peduncle in direct contact with blood capillaries underlying the epithelium. The second type of cells resulted to be formed by a globular body from which depart numerous processes; these cells, localized deeply in the choroid epithelium, strictly contact neighboring epithelial cells. No synaptic contacts were detected between these cell populations and common epithelial cells. To gain some insight into the functional properties of choroid cells, NADPH diaphorase (NADPHd) and neuronal nitric oxide synthase (nNOS) activities were evaluated. Of interest, whereas a strong NADPHd activity was detected in all cell types of choroid epithelium, nNOS was only detected in the first type of peculiar cells. The presence of nNOS in the CPs was confirmed by Western blotting. These results suggest that nitric oxide may serve as a signal for the regulation of CP multiple functions. Anat Rec, 290:1399,1412, 2007. © 2007 Wiley-Liss, Inc. [source] Impact of reducing intrinsic cognitive load on learning in a mathematical domainAPPLIED COGNITIVE PSYCHOLOGY, Issue 3 2006Paul Ayres This paper examines the effectiveness of instructional strategies that lower cognitive load by reducing task complexity (intrinsic cognitive load). Three groups of 13-year-old students were required to learn a mathematical task under different conditions. One group (Isolated) followed a strategy that used part-tasks where the constituent elements were isolated from each other (element isolation). A second group (Integrated) received whole tasks where all elements were fully integrated, and a third group (Mixed) followed a mixed strategy progressing from part-tasks to whole-tasks. Results indicated that the part-task strategy was effective in lowering cognitive load for all students, but only benefitted learning for students with low prior knowledge. In contrast, students with a higher prior knowledge learned significantly more having studied whole tasks during instruction compared with part-tasks. The mixed-mode method proved to be ineffective for both levels of prior knowledge. These results are discussed in terms of cognitive load theory. Copyright © 2006 John Wiley & Sons, Ltd. [source] Mononuclear Mixed ,-Ketoester-alkoxide Compound of Titanium as a Promising Precursor for Low-Temperature MOCVD of TiO2 Thin Films,CHEMICAL VAPOR DEPOSITION, Issue 6 2003R. Bhakta A monomeric titanium complex suitable for liquid-injection MOCVD applications is synthesized and its molecular structure is determined by single-crystal X-ray diffraction. [Ti(OiPr)2 -(tbaoac)2] (see Figure), (tbaoac),=,tertiarybutylacetoacetonate), is a volatile alkoxide-(beta)diketonate precursor that has a low melting point and very good solubility in common organic solvents. [source] The Proteolytic Stability of ,Designed' , -Peptides Containing , -Peptide-Bond Mimics and of Mixed ,,, -Peptides: Application to the Construction of MHC-Binding PeptidesCHEMISTRY & BIODIVERSITY, Issue 5 2005David Whereas , -peptides are rapidly degraded in vivo and in vitro by a multitude of peptidases, substrates constructed entirely of or incorporating homologated , -amino acid (i.e., , -amino acid) units exhibit a superior stability profile. Efforts made so far to proteolytically hydrolyze a ,, peptide bond have not proved fruitful; a study aimed at breaching this proteolytic stability is discussed here. A series of such bonds have been designed with side-chain groups similar in relative positions (constitution) and three-dimensional arrangements (configuration) as found about , -peptidic amide bonds. Increasing the prospect for degradation would permit the tuning of , -peptide stability; here, however, no cleavage was observed (1, 2, 4,6, Table,1). Peptides comprised of , - and , -amino acids (mixed ,,, -peptides, 8,11) are expected to benefit from both recognition by a natural receptor and a high level of proteolytic stability, ideal characteristics of pharmacologically active compounds. ,3 -Peptides containing , -amino acid moieties at the N-terminus are degraded, albeit slowly, by several peptidases. Of particular interest is the ability of pronase to cleave an ,, peptide bond, namely that of ,Ala,3hAla. Significantly, successful hydrolysis is independent of the configuration of the , -amino acid. Some of the ,,, -peptides discussed here are being investigated for their binding affinities to class I MHC proteins. The computer-programming steps required to prepare ,,, -peptides on an automated peptide synthesizer are presented. [source] Ordered Mesoporous Thin Films of Rutile TiO2 Nanocrystals Mixed with Amorphous Ta2O5CHEMPHYSCHEM, Issue 5 2008Jin-Ming Wu Dr. Abstract Ordered mesoporous thin films of composites of rutile TiO2 nanocrystals with amorphous Ta2O5 are fabricated by evaporation-induced self-assembly followed by subsequent heat treatment beyond 780,°C. Incorporation of selected amounts of Ta2O5 (20 mol,%) in the mesoporous TiO2 film, together with the unique mesoporous structure itself, increased the onset of crystallization temperature which is high enough to ensure the crystallization of amorphous titania to rutile. The ordered mesoporous structure benefits from a block-copolymer template, which stabilizes the mesostructure of the amorphous mixed oxides before crystallization. The surface and in-depth composition analysis by X-ray photoelectron spectroscopy suggests a homogeneous intermixing of the two oxides in the thin film. A detailed X-ray absorption fine structure measurement on the composite film containing 20 mol,% Ta2O5 and heated to 800,°C confirms the amorphous nature of the Ta2O5 phase. Photocatalytic activity evaluation suggests that the rutile nanocrystals in the synthesized ordered mesoporous thin film possess good ability to assist the photodegradation of rhodamine B in water under illumination by UV light. [source] Evaporation of Water Microdroplets on Self-Assembled Monolayers: From Pinning to ShrinkingCHEMPHYSCHEM, Issue 7 2004Hua-Zhong Yu Prof. The great escape: Mixed , -terminated self-assembled monolayers (SAMs) were explored as model surfaces to understand fundamental aspects of liquid evaporation phenomena on solids. The authors demonstrate that on these SAMs the evaporation of water microdroplets follows an exclusive trend. Despite the different wettabilities of the surfaces, the evaporation of water microdroplets switches from a constant contact area ("pinning") to a constant contact angle mode ("shrinking"). [source] Histologic Analysis of Clinical Biopsies Taken 6 Months and 3 Years after Maxillary Sinus Floor Augmentation with 80% Bovine Hydroxyapatite and 20% Autogenous Bone Mixed with Fibrin GlueCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2001Mats Hallman DDS Abstract: Background: Bovine hydroxyapatite (Bio-Oss®, Geistlich Pharmaceutical, Wollhausen, Switzerland) has been suggested to be used in maxillary sinus floor augmentation procedures prior to or in conjunction with implant placement. However, the long-term histologic fate of this material is not well understood. Purpose: The aim with this study was to histologically evaluate the tissue response in patients to a mixture of bovine hydroxyapatite (BH), autogenous bone, and fibrin glue 6 months and 3 years after a maxillary sinus floor augmentation procedure. Materials and Method: Biopsies were taken from a group of 20 consecutive patients 6 months (n = 16) and 3 years (n = 12) after maxillary sinus floor augmentation with a mixture of BH (80%), autogenous bone (20%), and fibrin glue and prepared for histologic analysis. Results: Light microscopy and morphometry from biopsies taken after 6 months showed various amounts of mineralized bone tissue. The specimen area was occupied by 54.1 ± 12.6% nonmineralized tissue, followed by 21.2 ± 24.5% lamellar bone, 14.5 ± 10.3% BH particles, and 10.2 ± 13.4% woven bone. The nonmineralized tissue seen in bone-forming areas consisted of a loose connective tissue, rich with vessels and cells. There were no signs of resorption of the BH particles. The lamellar bone appeared to have originated from the recipient site and was seldom in contact with the BH particles. After 3 years, the nonmineralized tissue area had decreased to 36.0 ± 19.0% (p > .05) and consisted mainly of bone marrow tissue. The surface area of lamellar bone had increased to 50.7 ± 22.8% (p > .05), and there was almost no immature bone. The mean specimen area occupied by BH particles, was 12.4 ± 8.7% and had not changed from 6 months (not significant). Moreover, the sizes of the particles were similar after 6 months and 3 years. The degree of BH particle,bone contact had increased from 28.8%± 19.9% after 6 months to 54.5 ± 28.8% after 3 years (p > .05). Conclusion: Histology of specimens from maxillary sinuses augmented with 80% BH particles, 20% autogenous bone, and fibrin glue showed a positive bone tissue response after 6 months and 3 years after augmentation of the maxillary sinus floor prior to implant placement in a group fo 20 patients. The bone surrounding and in contact with the BH particles after 6 months was mainly immature woven bone, which with time was replaced by mature lamellar bone filling the interparticle space as observed in the 3-year specimens. Moreover, bone-integrated BH particles seem to be resistant to resorption. The results indicate that the procedure may be considered when only small amounts of intraoral autogenous bone graft are available. [source] Synthesis, and Helix or Hairpin-Turn Secondary Structures of ,Mixed' ,/, -Peptides Consisting of Residues with Proteinogenic Side Chains and of 2-Amino-2-methylpropanoic Acid (Aib)HELVETICA CHIMICA ACTA, Issue 9 2006Dieter Seebach Abstract Twelve peptides, 1,12, have been synthesized, which consist of alternating sequences of , - and , -amino acid residues carrying either proteinogenic side chains or geminal dimethyl groups (Aib). Two peptides, 13 and 14, containing 2-methyl-3-aminobutanoic acid residues or a ,random mix' of ,-, ,2 -, and ,3 -amino acid moieties were also prepared. The new compounds were fully characterized by CD (Figs.,1 and 2), and 1H- and 13C-NMR spectroscopy, and high-resolution mass spectrometry (HR-MS). In two cases, 3 and 14, we discovered novel types of turn structures with nine- and ten-membered H-bonded rings forming the actual turns. In two other cases, 8 and 11, we found 14/15 -helices, which had been previously disclosed in mixed ,/, -peptides containing unusual , -amino acids with non-proteinogenic side chains. The helices are formed by peptides containing the amino acid moiety Aib in every other position, and their backbones are primarily not held together by H-bonds, but by the intrinsic conformations of the containing amino acid building blocks. The structures offer new possibilities of mimicking peptide,protein and protein,protein interactions (PPI). [source] A comparison of concurrent programming and cooperative multithreadingCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 1 2003Aaron W. Keen Abstract This paper presents a comparison of the cooperative multithreading model with the general concurrent programming model. It focuses on the execution time performance of a range of standard concurrent programming applications. The overall results are mixed. In some cases, programs written in the cooperative multithreading model outperform those written in the general concurrent programming model. The contributions of this paper are twofold. First, it presents a thorough analysis of the performances of applications in the different models, i.e. to explain the criteria that determine when a program in one model will outperform an equivalent program in the other. Second, it examines the tradeoffs in writing programs in the different programming styles. In some cases, better performance comes at the cost of more complicated code. Copyright © 2003 John Wiley & Sons, Ltd. [source] Outcomes and Prognostic Factors of Systolic as Compared With Diastolic Heart Failure in Urban AmericaCONGESTIVE HEART FAILURE, Issue 1 2005Peter A. McCullough MD We sought to describe a large heart failure (HF) population with respect to systolic and diastolic abnormalities in terms of demographics, echocardiographic parameters, and survival. Using data abstracted from the Resource Utilization Among Congestive Heart Failure (REACH) study, a targeted subpopulation of 3471 patients had electrocardiographic, echocardiographic, and clinical data taken from automated sources during the first year of diagnosis. Among the HF population, 1811 (52.2%) had diastolic HF. Prevalence of diastolic HF trended with age, from 46.4% in those less than 45 years to 58.7% in those 85 years or older (p=0.001 for trend). Patients with diastolic HF had a higher mean ejection fraction (55.7% vs. 28.0%), lower left ventricular end-systolic diameter (3.11 vs. 4.74 cm), and lower left atrium: aortic outlet ratio (1.28 vs. 1.38) (p=0.001 for each comparison). Annualized age, sex, and race-adjusted mortality were 11.2% and 13.0% for those with diastolic and systolic HF, respectively (p=0.001). In a large, racially mixed, urban HF population, those with diastolic HF predominate and enjoy better-adjusted survival than counterparts with systolic HF. [source] OBESITY AND NUTRIENT CONSUMPTION: A RATIONAL ADDICTION?CONTEMPORARY ECONOMIC POLICY, Issue 3 2007TIMOTHY J. RICHARDS Recent research shows that the dramatic rise in obesity in the United States is due more to the overconsumption of unhealthy foods than underactivity. This study tests for an addiction to food nutrients as a potential explanation for the apparent excessive consumption. A random coefficients (mixed) logit model is used to test a multivariate rational addiction model. The results reveal a particularly strong addiction to carbohydrates. The implication of this finding is that price-based policies, sin taxes, or produce subsidies that change the expected future costs and benefits of consuming carbohydrate-intensive foods may be effective in controlling excessive nutrient intake. (JEL D120, I120, C230) [source] MR imaging for the longevity of mesenchymal stem cells labeled with poly- L -lysine,Resovist complexesCONTRAST MEDIA & MOLECULAR IMAGING, Issue 2 2010Gang Liu Abstract Superparamagnetic iron oxide (SPIO) nanoparticles are emerging as ideal probes for noninvasive cell tracking. In this study, poly- L -lysine (PLL) was mixed with Resovist to form the PLL,Resovist complexes and the control of the complexes formed by PLL and Resovist and their subsequent properties was easily achievable. MSCs could be safely and efficiently labeled for MR imaging using PLL,Resovist complexes (w/w 0.01:1) and the labeled MSCs could be detected to have definite decreased signal intensity on T2 -weight imaging until 20 days with standard 1.5,T MR equipment. This study describes a simple protocol to label MSCs using PLL,Resovist complexes and the results presented in our study can provide a basis for the application of PLL,Resovist complexes cell labeling. Copyright © 2010 John Wiley & Sons, Ltd. [source] MR imaging in assessing cardiovascular interventions and myocardial injuryCONTRAST MEDIA & MOLECULAR IMAGING, Issue 1 2007Alexis Jacquier Abstract Performing an MR-guided endovascular intervention requires (1) real-time tracking and guidance of catheters/guide wires to the target, (2) high-resolution images of the target and its surroundings in order to define the extent of the target, (3) performing a therapeutic procedure (delivery of stent or injection of gene or cells) and (4) evaluating the outcome of the therapeutic procedure. The combination of X-ray and MR imaging (XMR) in a single suite was designed for new interventional procedures. MR contrast media can be used to delineate myocardial infarcts and microvascular obstruction, thereby defining the target for local delivery of therapeutic agents under MR-guidance. Iron particles, or gadolinium- or dysprosium-chelates are mixed with the soluble injectates or stem cells in order to track intramyocardial delivery and distribution. Preliminary results show that genes encoded for vascular endothelial and fibroblast growth factor and cells are effective in promoting angiogenesis, arteriogenesis, perfusion and LV function. Angiogenic growth factors, genes and cells administered under MR-guided minimally invasive catheter-based procedures will open up new avenues in treating end-stage ischemic heart disease. The optimum dose of the therapeutic agents, delivery devices and real-time imaging techniques to guide the delivery are currently the subject of ongoing research. The aim of this review is to (1) provide an updated review of experiences using MR imaging to guide transcatheter therapy, (2) address the potential of cardiovascular magnetic resonance (MR) imaging and MR contrast media in assessing myocardial injury at a molecular level and labeling cells and (3) illustrate the applicability of the non-invasive MR imaging in the field of angiogenic therapies through recent clinical and experimental publications. Copyright © 2007 John Wiley & Sons, Ltd. [source] INVESTIGATING RACIAL PROFILING BY THE MIAMI-DADE POLICE DEPARTMENT: A MULTIMETHOD APPROACHCRIMINOLOGY AND PUBLIC POLICY, Issue 1 2007GEOFFREY P. ALPERT Research Summary The perception and existence of biased policing or racial profiling is one of the most difficult issues facing contemporary American society. Citizens from minority communities have focused their concerns on the improper use of race by law enforcement officers. The current research uses a complex methodological approach to investigate claims that the Miami-Dade, Florida Police Department uses race improperly for the purposes of making traffic stops and conducting post-stop activities. The results are mixed in that the officer's aggregate actions do not show a pattern of discriminatory actions toward minority citizens when making a traffic stop, but results of post-stop activities do show some disparate treatment of minorities. Policy Implications Five specific policy recommendations are made to reduce the perception or reality of racial profiling by the police. First, police departments must have clear policies and directives explaining the proper use of race in decision making. Second, officers must be trained and educated in the overall impact of using race as a factor in deciding how to respond to a citizen. Third, the department must maintain a data-collection and analytic system to monitor the activities of their officers as it pertains to the race of the citizen. The fourth police recommendation involves the use of record checks in the field that can set in motion a process that results in the detention and arrest of citizens. Fifth, the completion of a record of interrogation for later intelligence has implications for the citizen. The use of this intelligence tool must depend on suspicion rather than on the race of the citizen. [source] Effect of citric acid and 1,2-dihydroxybenzene 3,5-disulfonic acid on crystallization of calcium sulfate dihydrate under simulated conditions of phosphoric acid productionCRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2005M. M. Rashad Abstract The effect of citric acid and 1,2-dihydroxybenzene 3,5-disulfonic acid (DHBDSA), as additives, on the crystallization of gypsum was studied under simulated conditions of the of phosphoric acid production. Calcium hydrogen phosphate and sulfuric acid were mixed with dilute phosphoric acid at 80 °C, and the turbidity of the reaction mixture was measured at different time periods to calculate the induction time of gypsum crystals formation. Addition of citric acid increased the induction time and decreased the growth efficiency while addition of DHBDSA decreased the induction time and increased the growth efficiency compared with in absence of additives. The crystals mean and median diameters were found to decrease in the presence of citric acid and increased in the presence of DHBDSA. The surface energy decreased with citric acid and increased with DHBDSA compared to the baseline (without additives). Interestingly, the majority of the formed crystals are tabular with DHBDSA and needle-like type with citric acid and baseline [source] Reverse Auctions with Multiple Reinforcement Learning Agents,DECISION SCIENCES, Issue 1 2008Subhajyoti Bandyopadhyay ABSTRACT Reverse auctions in business-to-business (B2B) exchanges provide numerous benefits to participants. Arguably the most notable benefit is that of lowered prices driven by increased competition in such auctions. The competition between sellers in reverse auctions has been analyzed using a game-theoretic framework and equilibria have been established for several scenarios. One finding of note is that, in a setting in which sellers can meet total demand with the highest-bidding seller being able to sell only a fraction of the total capacity, the sellers resort to a mixed-strategy equilibrium. Although price randomization in industrial bidding is an accepted norm, one might argue that in reality managers do not utilize advanced game theory calculations in placing bids. More likely, managers adopt simple learning strategies. In this situation, it remains an open question as to whether the bid prices converge to the theoretical equilibrium over time. To address this question, we model reverse-auction bidding behavior by artificial agents as both two-player and n -player games in a simulation environment. The agents begin the game with a minimal understanding of the environment but over time analyze wins and losses for use in determining future bids. To test for convergence, the agents explore the price space and exploit prices where profits are higher, given varying cost and capacity scenarios. In the two-player case, the agents do indeed converge toward the theoretical equilibrium. The n -player case provides results that reinforce our understanding of the theoretical equilibria. These results are promising enough to further consider the use of artificial learning mechanisms in reverse auctions and other electronic market transactions, especially as more sophisticated mechanisms are developed to tackle real-life complexities. We also develop the analytical results when one agent does not behave strategically while the other agent does and show that our simulations for this environment also result in convergence toward the theoretical equilibrium. Because the nature of the best response in the new setting is very different (pure strategy as opposed to mixed), it indicates the robustness of the devised algorithm. The use of artificial agents can also overcome the limitations in rationality demonstrated by human managers. The results thus have interesting implications for designing artificial agents in automating bid responses for large numbers of bids where human intervention might not always be possible. [source] An update on the role of glutamate in the pathophysiology of depressionACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010N. D. Mitchell Mitchell ND, Baker GB. An update on the role of glutamate in the pathophysiology of depression. Objective:, To review the literature on the involvement of glutamate (Glu), including its interactions with other neurochemical systems, in the pathophysiology of depression. Method:, A MEDLINE search using the terms glutamate, depression and major depressive disorder, was performed. Results:, Alterations in proteins involved in glutamatergic signalling are implicated in variations in behaviour in animal models of depression. Drugs acting at Glu receptors appear to have antidepressant-like effects in these models, and traditional antidepressant pharmacotherapies act on the glutamatergic system. Recent evidence from genetic studies and in vivo spectroscopy also correlate glutamatergic dysfunction with depression. Trials of N -methyl- d -aspartate receptor antagonists in humans have provided mixed results. Conclusion:, A growing body of evidence indicates that the glutamatergic system is involved in the pathophysiology of depression, and may represent a target for intervention. [source] Protective effect of Copalite surface coating on mercury release from dental amalgam following treatment with carbamide peroxideDENTAL TRAUMATOLOGY, Issue 3 2000I. Rotstein Abstract , The effect of Copalite coating on mercury release from dental amalgam following treatment with 10%, 20%, 30% and 40% carbamide peroxide was assessed in vitro, using a cold-vapour atomic absorption Mercury Analyzer System. Eighty samples of dental amalgam were automatically mixed in a dental amalgamator and condensed into silicon embedding molds. Forty amalgam samples were coated with three uniform layers of Copalite intermediary varnish and the other 40 samples were left uncoated. The coated and non-coated amalgam samples were exposed for 24 h to 10%, 20%, 30% or 40% carbamide peroxide preparations and compared with samples exposed to phosphate buffer. In the non-coated samples a significant increase of mercury concentration in solution was found following exposure to all carbamide peroxide preparations tested. Mercury concentration was directly related to carbamide peroxide concentration. In the Copalite-coated samples, significantly lower concentrations of mercury in solution were found as compared to the non-coated samples (P<0.01). In conclusion, exposure of amalgam restorations to 10%,40% carbamide peroxide-based bleaching agents increased the mercury release. Pre-coating of the external amalgam surfaces with Copalite significantly reduced the release of mercury. [source] False memory and obsessive,compulsive symptomsDEPRESSION AND ANXIETY, Issue 5 2009Heide Klumpp Ph.D Abstract Background: The memory deficit hypothesis has been used to explain the maintenance of repetitive behavior in individuals with obsessive,compulsive disorder, yet the majority of studies focusing on verbal memory show mixed results. These studies primarily evaluated memory accuracy via the inclusion or omission of previously encountered material, as opposed to false recognition (i.e., the inclusion of erroneous material). We evaluated false memories and memory processes in individuals with obsessive,compulsive washing symptoms (OC), individuals matched on depression and anxiety without OC symptoms (D/A), and in nonanxious individuals (NAC). Methods: Twenty-eight OC, 28 D/A, and 29 NAC individuals read OC-threat relevant, positive, and neutral scenarios and then performed a recognition test. Erroneous recognition of words associated to encoded, but not previously viewed, scenarios were classified as false memories. To evaluate processes underlying memory, participants completed a modified remember/know task to examine whether the OC individuals differed from the other individuals in recollective clarity for false memories of OC-relevant (e.g., germs), positive (e.g., lottery), and neutral (e.g., bread) material. Results: The OC individuals used "know" more than the D/A and NAC individuals for false memories of threat. For veridical memories, the OC individuals used "know" more than the NAC, but not, D/A individuals. Conclusions: The greater reliance on "know" (i.e., feelings of familiarity) in general and false threat memories in particular in individuals with OC symptoms may add to feelings of uncertainty for threat-relevant material, which may contribute to compulsive behavior. Depression and Anxiety, 2009. ©2008 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||||||||