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Kinds of This Terms modified by This Selected AbstractsInteraction between a dislocation and monovalent anion in various alkali halide crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10 2010Y. KohzukiArticle first published online: 30 AUG 2010 Abstract It was investigated from (L0/L)2 versus ,0 curve that the Friedel relation between the effective stress and the average length of dislocation segments, L, is appropriate for the interaction between a dislocation and the monovalent anion in various alkali halides single crystals (NaCl: Br - , NaBr: Cl - or I - , KCl: Br - or I - , and RbCl: Br - or I - ). Here, L0 represents the average spacing of monovalent anions on a slip plane and ,0 is the bending angle at which the dislocation breaks away from the anion at the temperature of 0 K. This is because the anions are the weak obstacles such as impede the dislocation at ,0 above about 150 degrees, where the Friedel relation agrees with the Fleischer one (L02 = L2(,,,0)/2). Furthermore, the values of (L /L0) were found to be within 4.05 to 5.87 for the crystals. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] "When I Grow Up I'd Like to Work in a Place Like This": Museum Professionals' Narratives of Early Interest in MuseumsCURATOR THE MUSEUM JOURNAL, Issue 1 2000MICHAEL SPOCK ABSTRACT As part of an exploratory research study, museum professionals were asked to share their stories about pivotal learning experiences in museums. Several offered personal narratives of how they first became interested in museums and started down the path toward careers in museum work, or had their imaginations opened to the possibility of broader life horizons. This group of stories seemed to be grounded in particularly vivid memories and frequently elicited strong emotions in the telling. The narratives are evidence of the impact of early museum experiences on people who later found their way into museum careers, and suggest avenues for further study of the roots of museum careers as well as other ways museums profoundly affect people's lives. The stories can also reveal to the teller, as well as to researchers and others, what stands out in their memories and the importance they assign to those memories. By attending to the thematic and emotional content of these narratives, both narrator and colleagues can find clues about where their beliefs and values really lie and, therefore, where their and the profession's time and resources might be most productively invested. [source] Lateral Wedge Resection: A Simple Technique for Repairing Involutional Lower Eyelid EntropionDERMATOLOGIC SURGERY, Issue 9 2010IGAL LEIBOVITCH MD BACKGROUND Lower lid involutional entropion is a common eyelid pathology affecting the elderly population. Most of the reported surgical techniques are mainly based on a lateral tarsal strip anchored to the orbital rim. OBJECTIVES To report the surgical outcome using a simple single-stitch lateral wedge technique to repair involutional lower entropion. METHODS This single-surgeon, retrospective, noncomparative cases series included all patients with involutional lower eyelid entropion who were operated on using the lateral wedge technique. RESULTS Fifty-eight eyelids of 52 patients (46 unilateral, 6 bilateral; 27 men, 25 women; age, mean 67±10; range 50,85) underwent surgical repair. Immediate resolution of entropion and associated ocular symptoms was achieved in 55 eyelids (94.9%). One case had postoperative ectropion that completely resolved spontaneously after 4 weeks, and one had wound dehiscence that healed completely without any intervention. Another patient had residual entropion that resolved after an additional surgical repair. No other cases of recurrence were noted during a mean follow-up period of 16 months (range 6,24 months). CONCLUSION This minimally invasive single-stitch lateral wedge technique is a simple and effective procedure for repairing involutional lower eyelid entropion and is associated with low recurrence and complication rates. Igal Leibovitch, MD, has indicated no significant interest with commercial supporters. [source] Use of High-Frequency, High-Resolution Ultrasound Before Mohs SurgeryDERMATOLOGIC SURGERY, Issue 6 2010ELLEN S. MARMUR MD BACKGROUND Although ultrasound imaging is employed ubiquitously today, its use to examine and assess the skin is a relatively new technology. We explored the clinical application and use of high-frequency, high-resolution ultrasound in Mohs micrographic surgery. OBJECTIVE To evaluate the ability of ultrasound to accurately determine lesion length and width of tumor borders in order to reduce the number of surgical stages. METHODS AND MATERIALS This was an institutional review board,approved single-center study of 26 Mohs surgery patients. Ultrasound images were taken to record lesion dimensions, and then the investigator documented clinical estimation of the first stage. Extirpation of the tumor and histological analysis were performed thereafter. RESULTS The results of 20 patients were included in the analysis. A paired-samples t -test revealed no significant difference between clinical and ultrasound widths (t=,1.324, p=.20). Similarly, there was no significant difference between the lengths found from clinical assessment and ultrasound (t=,1.093, p=.29). For different tumor types, there was no significant difference between clinical and ultrasound widths or lengths for basal cell carcinoma (t=,1.307, p=.23; t=,1.389, p=.20) or squamous cell cancer (t=,0.342, p=.73; t=0.427, p=.68). CONCLUSION There is a diagnostic role for high-resolution ultrasound in Mohs surgery regarding the delineation of surgical margins, but its limitations preclude its practical adoption at this time. The ultrasound equipment was loaned to the investigators. Funding for the study was provided by Longport, Inc. [source] Cosmetic Use of Poly- l -Lactic Acid: A Retrospective Study of 130 PatientsDERMATOLOGIC SURGERY, Issue 2 2010MELANIE D. PALM MD BACKGROUND Poly- l -lactic acid (PLLA) is an effective treatment for patients seeking to correct volume loss due to aging. Although the Food and Drug Administration has approved PLLA for use in people with the human immunodeficiency virus (HIV), it is well-suited for patients seeking cosmetic treatment. OBJECTIVE To evaluate the efficacy and incidence of adverse events of HIV-negative patients treated with PLLA for volume restoration. MATERIALS AND METHODS This is a retrospective, single-center study of 130 HIV-negative patients treated with PLLA from 2003 to 2008. Patient satisfaction and incidence of adverse reactions were evaluated. RESULTS The most common reaction to PLLA treatment was the formation of nodules (8.5%). Almost all of the nodules were palpable; only one was visible. Treatment areas with the highest incidence of post-treatment nodules were the hands (12.5%) and cheeks (7.2%). Overall, patients were satisfied, with 55% having good to excellent correction; 75% of patients with five or more treatments rated their correction as good to excellent. Sixty-eight percent of all patients would repeat the procedure again. CONCLUSION PLLA is a safe, biodegradable volumizer used to reverse the signs of aging by gradually correcting volume loss. Patients should be aware of possible adverse reactions during the course of treatment. Nodule formation is low, with most patients having good to excellent correction. Drs. Butterwick and Goldman are consultants for Sanofi-Aventis. [source] Prevalence of Methicillin-Resistant Staphylococcus aureus in the Setting of Dermatologic SurgeryDERMATOLOGIC SURGERY, Issue 3 2009ROGER S. SICA DO BACKGROUND The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in the postoperative setting of dermatologic surgery is unknown. Such data could influence the empirical treatment of suspected infections. OBJECTIVE To examine the period prevalence of MRSA infections in the postoperative setting of dermatologic surgery. METHODS We performed chart reviews of 70 patients who had bacterial cultures taken from January 2007 to December 2007. In the 21 postsurgical cases, we analyzed age, risk factors, sites of predilection, method of repair, and pathogen of growth. RESULTS The mean age of the overall study population was 57, with the mean age of postsurgical MRSA-positive cases being 75.5. Of the 21 postsurgical cultures taken, 16 cultures grew pathogen, and two of the 16 (13%) pathogen-positive cultures grew MRSA. LIMITATIONS This is a retrospective chart review of a relatively small sample size in one geographic location. Our patient population is known to contain a large number of retirees. CONCLUSION The increasing prevalence of MRSA skin and soft tissue infections and recommendation to modify empirical antibiotic therapy have been well documented in particular patient populations, but we caution against the empirical use of MRSA-sensitive antibiotics in the postoperative setting of dermatologic surgery. We advocate culturing all infectious lesions upon presentation and reserve empirical use of MRSA-sensitive antibiotics for high-risk patients or locations. [source] Persistence and Improvement of Nasolabial Fold Correction with Nonanimal-Stabilized Hyaluronic Acid 100,000 Gel Particles/mL Filler on Two Retreatment Schedules: Results up to 18 Months on Two Retreatment SchedulesDERMATOLOGIC SURGERY, Issue 2008RHODA S. NARINS MD BACKGROUND Nonanimal-stabilized hyaluronic acid (NASHA) fillers are frequently used for facial soft tissue augmentation. Their long-term efficacy and the effects of different retreatment schedules are not well established. OBJECTIVE This is an 18-month interim analysis of a 30-month study to evaluate the efficacy and persistence of NASHA 100,000 gel particles/mL filler with two different retreatment schedules. METHODS This multicenter, randomized, evaluator-blinded study enrolled 75 patients with moderate to severe nasolabial folds. Patients were randomized to retreatment of one nasolabial fold at 4.5 months and the contralateral fold at 9 months after correction of both folds at the initial visit. RESULTS Wrinkle Severity Rating Scale scores improved significantly (p<.001) from baseline, with mean improvements ranging from 1.1 to 1.7 grades. Almost all patients (97%) responded satisfactorily, and the efficacy of the retreatment schedules did not differ significantly. Adverse events, primarily swelling and bruising, occurred in 33% of patients; none were serious. CONCLUSION The improvements seen after initial treatment with NASHA 100,000 gel particles/mL filler persisted for up to 18 months with one retreatment. The response was equivalent for retreatment at 4.5 and 9 months. [source] Fractional Photothermolysis for Photoaging of HandsDERMATOLOGIC SURGERY, Issue 1 2008MING H. JIH MD BACKGROUND Laser treatment for photoaging of the hands should ideally address pigmentary alteration as well as associated skin roughness and wrinkling. Fractional resurfacing has been previously shown to effectively treat facial rhytids and dyschromia. OBJECTIVE We examined the effect of fractional resurfacing for photoaging of the hands. METHODS AND MATERIALS Ten patients (skin phototypes II to IV) with hand photodamage were randomized to receive five treatments with a 1,550-nm diode-pumped erbium fiber laser (Fraxel SR, Reliant Technologies) laser on either the right or left hand. Treatments were performed at settings of 8 to 9 mJ/microscopic treatment zone and density of 2,500 microscopic treatment zones/cm2. Subjective assessments by the patients and investigator were performed for skin roughness, wrinkling, and pigmentation using a 5-point scale. Skin biopsies were taken at baseline and at 1 and 3 months. RESULTS Patient subjective assessment and physician clinical assessment at 1 and 3 months revealed a mean 51% to 75% improvement in skin pigmentation and 25% to 50% improvement in skin roughness and wrinkling. Biopsies of the skin showed increased density of dermal collagen. Patients experienced transient erythema and edema and none had scarring or other adverse effects. LIMITATIONS This was a small study. CONCLUSION Fractional resurfacing appears to be an effective and safe treatment modality for correcting both the pigmentary and the textural aspects of photoaging of the hand. [source] Autologous Cultured Fibroblast Injection for Facial Contour Deformities: A Prospective, Placebo-Controlled, Phase III Clinical TrialDERMATOLOGIC SURGERY, Issue 3 2007ROBERT A. WEISS MD BACKGROUND Previous data indicate that injections of autologous fibroblasts increase collagen formation, accompanied by a concomitant increase in thickness and density of dermal collagen. OBJECTIVE The purpose of this study was to determine efficacy and side effects of autologous living fibroblast injections versus placebo in a randomized Phase III trial for the treatment of various facial contour defects. METHODS This was a double-blind, randomized comparison of injectable living autologous fibroblast cells and placebo for the treatment of facial contour defects (N=215). Live fibroblasts (20 million/mL) or placebo (the transport medium without living cells) were given as three doses administered at 1- to 2-week intervals. Efficacy evaluations were performed 1, 2, 4, 6, 9, and 12 months after the first injection. RESULTS Living fibroblasts produced statistically significantly greater improvements in dermal deformities and acne scars than did placebo. The difference between live fibroblast injections and placebo achieved statistical significance at 6 months (p<.0001). At 9- and 12-month follow-up, live fibroblast,treated patients continued to demonstrate benefit from treatment with response rates of 75.0 and 81.6%, respectively. No serious treatment-related adverse events were reported. CONCLUSIONS Our results indicate that autologous fibroblast injections can safely and effectively produce improvements in rhytids, acne scars, and other dermal defects continuing for at least 12 months after injection. [source] Multiple Primary Acral Melanomas in African-Americans: A Case Series and Review of the LiteratureDERMATOLOGIC SURGERY, Issue 1 2007ANGELA C. S. HUTCHESON MD BACKGROUND Although melanoma accounts for only 4% to 5% of all skin cancers in the United States, it causes most skin cancer,related deaths. We describe a unique group of African-American patients with multiple primary acral lentiginous melanomas (ALMs). OBJECTIVE The purpose of this study was to review the case histories and management of a cohort of patients in the Mohs practice of our dermatologic surgeon with multiple primary ALM. METHODS This is a case series of patients with multiple ALM identified by chart review from 2000 to 2005. A thorough review of the literature was performed. RESULTS Four patients, all African-American, were identified with multiple ALM. All patients were managed with excision or Mohs micrographic surgery utilizing permanent sections. None of the patients with ALM had melanomas at nonacral sites or other types of skin cancer. Several had acral melanosis. Information in the literature on patients with multiple primary acral melanomas was insufficient. CONCLUSION Patients with multiple acral melanomas have not, to our knowledge, been reported thus far. It can be extrapolated from current literature, however, that appropriate management of these patients, including staging work and surgical intervention, is to be determined by the individual characteristics of the melanoma and the patient's concomitant risk factors, if any. [source] Use of Honey as an Adjunct in the Healing of Split-Thickness Skin Graft Donor SiteDERMATOLOGIC SURGERY, Issue 2 2003Aykut Misirlioglu MD BACKGROUND Different techniques are being used in treatment of split-thickness skin graft donor sites; however, there is not a widely accepted method established for these partial-thickness wounds. It is well known that honey has been very effective in the treatment of various types of wounds, but there is not any information about the usage of honey as split-thickness skin graft donor site dressing in the literature. OBJECTIVE To evaluate and compare the effectiveness of honey-impregnated gauzes, hydrocolloid dressings, and as a conventional dressing, saline-soaked gauzes for skin graft donor sites. METHODS This is a nonrandomized, prospective, open-label (noncontrolled), side-by-side comparison trial of various options that are available for second-intention healing of donor site for split-thickness skin grafts. Eighty-eight patients who underwent skin grafting were observed using two different groups. In the first group, the donor site was divided into two equal halves, with each half being treated with honey-soaked gauzes and the other half with paraffin gauzes (group 1A), hydrocolloid dressings (group 1B), and saline-soaked gauzes (group 1C) alternatively. In the second group, two separate donor sites were formed, with one of them being treated with honey-impregnated gauzes (groups 2A,C) and the other one treated with either paraffin gauzes (group 2A), hydrocolloid dressings (group 2B), or saline-soaked gauzes (group 2C). The healing time, rate of infection, and sense of pain were evaluated. RESULTS In the treatment of split-thickness skin graft donor sites, honey-impregnated gauzes showed faster epithelization time and a low sense of pain than paraffin gauzes and saline-soaked gauzes. There was no significant difference between honey-impregnated gauzes and hydrocolloid dressings with regard to epithelization time and sense of pain. CONCLUSION The use of honey-impregnated gauzes is effective, safe, and practical. Honey can be an alternative material for the split-thickness skin graft donor site treatment. [source] Adding biphasic insulin aspart 30 once or twice daily is more efficacious than optimizing oral antidiabetic treatment in patients with type 2 diabetesDIABETES OBESITY & METABOLISM, Issue 5 2007W. M. W. Bebakar Aim:, To evaluate the efficacy and safety of adding biphasic insulin aspart 30 (BIAsp30; NovoMix® 30) to existing oral antidiabetic agents (OADs) vs. optimizing OADs in a subgroup of Western Pacific patients with type 2 diabetes inadequately controlled on oral monotherapy or oral combination therapy. Methods:, This 26-week, multi-centre, open-labelled, randomized, two-arm parallel trial consisted of a 2-week screening period, followed by 24 weeks of treatment. Subjects randomized to BIAsp30 treatment (n = 129) received BIAsp30 once daily (o.d.) at dinnertime between Week 2 and Week 14, and those not reaching treatment targets were switched to twice daily (b.i.d.) BIAsp30 at Week 14 (n = 50). Subjects randomized to the OAD-only arm (n = 63) continued with their previous OAD treatment and, in an attempt to reach treatment goals, the dose was optimized (but OAD unchanged) in accordance to local treatment practice and labelling. Results:, Significantly greater reductions in HbA1c over Weeks 0,13 with BIAsp30 (o.d.) vs. OAD-only treatment (1.16 vs. 0.58%; p < 0.001), and over Weeks 0,26, with BIAsp30 (o.d.) and BIAsp30 (b.i.d.) treatments vs. OAD-only treatment (1.24 vs. 1.34 vs. 0.67%; p < 0.01). Hypoglycaemic episodes were reported in 54% of the patients in BIAsp30 (o.d. and b.i.d. pooled) and 30% of the patients in OAD-only group. All episodes were minor or symptomatic, except for one in each treatment group, which was major. Conclusions:, Initiating BIAsp30 treatment is a safe and more effective way to improve glycaemic control in Western Pacific patients with type 2 diabetes inadequately controlled with oral monotherapy or oral combination therapy compared with optimizing oral combination therapy alone. In patients not reaching treatment target on BIAsp30 (o.d.), treatment with BIAsp30 (b.i.d.) should be considered. [source] Low-level defective processing of non-verbal sounds in dyslexic childrenDYSLEXIA, Issue 2 2009Paulino Uclés Abstract We compared processing of non-verbal auditory stimuli by dyslexic and non-dyslexic children using electrophysiological methods. The study included 39 children (17 with dyslexia plus 22 controls) assessed via frontal, central, parietal, and temporal electrodes. As an extension of previous P300 event-related potential studies, we analysed variations in the power values of 40-Hz oscillations (gamma-band oscillations involved in cognitive processing) during a specific time window in response to the auditory ,oddball' paradigm that entail target (random 2,kHz) and standard (frequent 1,kHz) stimuli. Dyslexic children differed significantly from controls (P<0.001) in the mean power of the wavelet-transformed 40-Hz oscillation in a time interval starting at 25 ms after stimulus onset up to 50 ms. This means defective processing of sounds. Within groups, standard and target tones elicited significantly different power values (P<0.001). Correlations of values between standard and target responses at each electrode position were not significant within either group, although dyslexics showed a lower correlation than controls. Significant differences in the mean power of these oscillations detected at very early stages of auditory processing in dyslexic children and the wide range of mean values reveal impairment in processing non-verbal sounds in dyslexia. Our results also support recent findings using behavioural and electrophysiological methods suggesting that dyslexia is a general auditory deficit instead of a speech-specific deficit. Copyright © 2008 John Wiley & Sons, Ltd. [source] Impact of a rock avalanche on a moraine-dammed proglacial lake: Laguna Safuna Alta, Cordillera Blanca, PeruEARTH SURFACE PROCESSES AND LANDFORMS, Issue 10 2005Bryn Hubbard Abstract Moraines that dam proglacial lakes pose an increasing hazard to communities in the Andes and other mountain ranges. The moraines are prone to failure through collapse, overtopping by lake waters or the effect of displacement waves resulting from ice and rock avalanches. Resulting floods have led to the loss of thousands of lives in the Cordillera Blanca mountains of Peru alone in the last 100 years. On 22 April 2002 a rock avalanche occurred immediately to the south-west of Laguna Safuna Alta, in the Cordillera Blanca. The geomorphic evidence for the nature, magnitude and consequences of this event was investigated in August 2002. Field mapping indicated that the avalanche deposited 8,20 × 106 m3 of rock into the lake and onto the surface of the frontal region of Glaciar Pucajirca, which flows into the lake. Repeated bathymetric surveying indicated that ,5 × 106 m3 of this material was deposited directly into the lake. The immediate effect of this event was to create a displacement wave that gained in height as it travelled along the lake basin, overtopping the impounding moraine at the lake's northern end. To achieve overtopping, the maximum wave height must have been greater than 100 m. This, and subsequent seiche waves, caused extensive erosion of both the proximal and distal faces of the impounding terminal moraine. Further deep gullying of the distal face of this moraine resulted from the supply of pressurized water to the face via a relief overflow tunnel constructed in 1978. Two-dimensional, steady-state analysis of the stability of the post-avalanche moraine rampart indicates that its proximal face remains susceptible to major large-scale rotational failure. Copyright © 2005 John Wiley & Sons, Ltd. [source] Macro-scale bed roughness of the siple coast ice streams in West AntarcticaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 13 2004Martin J. Siegert Abstract Subglacial bed conditions are key to understanding ice stream behaviour and evolution, with bed roughness re,ecting substrate composition and ,ow resistance. Here we present an analysis of bed roughness in the Siple Coast region of West Antarctica from airborne radio-echo sounding data. The ice streams are associated generally with low bed roughness values, which decrease downstream. The bed of the slow-,owing Ice Stream C (,10 000 km2) is also characterized by being smooth at all scales (wavelengths ranging from 5 km to in excess of 40 km). Furthermore, the bed is smooth either side of Ice Stream C. This suggests the location of the ice stream is controlled by internal ice sheet dynamics rather than by bed morphology. If the ice stream were encouraged to migrate laterally, when active, there would be little resistance offered by the subglacial morphology. Other inter-ice stream regions are rough, however, indicating a subglacial topographic in,uence on ice stream position. Bed roughness increases up-,ow of ice streams, which, unless the bed is modi,ed, may limit the inland migration of these systems. Copyright © 2004 John Wiley & Sons, Ltd. [source] Decision Theory Applied to an Instrumental Variables ModelECONOMETRICA, Issue 3 2007Gary Chamberlain This paper applies some general concepts in decision theory to a simple instrumental variables model. There are two endogenous variables linked by a single structural equation; k of the exogenous variables are excluded from this structural equation and provide the instrumental variables (IV). The reduced-form distribution of the endogenous variables conditional on the exogenous variables corresponds to independent draws from a bivariate normal distribution with linear regression functions and a known covariance matrix. A canonical form of the model has parameter vector (,, ,, ,), where ,is the parameter of interest and is normalized to be a point on the unit circle. The reduced-form coefficients on the instrumental variables are split into a scalar parameter ,and a parameter vector ,, which is normalized to be a point on the (k,1)-dimensional unit sphere; ,measures the strength of the association between the endogenous variables and the instrumental variables, and ,is a measure of direction. A prior distribution is introduced for the IV model. The parameters ,, ,, and ,are treated as independent random variables. The distribution for ,is uniform on the unit circle; the distribution for ,is uniform on the unit sphere with dimension k-1. These choices arise from the solution of a minimax problem. The prior for ,is left general. It turns out that given any positive value for ,, the Bayes estimator of ,does not depend on ,; it equals the maximum-likelihood estimator. This Bayes estimator has constant risk; because it minimizes average risk with respect to a proper prior, it is minimax. The same general concepts are applied to obtain confidence intervals. The prior distribution is used in two ways. The first way is to integrate out the nuisance parameter ,in the IV model. This gives an integrated likelihood function with two scalar parameters, ,and ,. Inverting a likelihood ratio test, based on the integrated likelihood function, provides a confidence interval for ,. This lacks finite sample optimality, but invariance arguments show that the risk function depends only on ,and not on ,or ,. The second approach to confidence sets aims for finite sample optimality by setting up a loss function that trades off coverage against the length of the interval. The automatic uniform priors are used for ,and ,, but a prior is also needed for the scalar ,, and no guidance is offered on this choice. The Bayes rule is a highest posterior density set. Invariance arguments show that the risk function depends only on ,and not on ,or ,. The optimality result combines average risk and maximum risk. The confidence set minimizes the average,with respect to the prior distribution for ,,of the maximum risk, where the maximization is with respect to ,and ,. [source] Bonding Form Analysis of Metals and Sulfur Fractionation in Methanol-Grown Anaerobic Granular SludgeENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 5 2007A. van der Veen Abstract This study investigates the metal and sulfur bonding form distribution in mesophilic (30,°C, pH 7) methanol-grown anaerobic granular sludge from upflow anaerobic sludge bed reactors operating at an organic loading rate of 3.8,g CH3OH-COD/L d. This was achieved by applying a modified Tessier sequential extraction scheme to investigate the metal bonding forms and a sequential extraction scheme for sulfur and simultaneously extracted metals to granular sludge samples of the reactors after 0, 22, 35 and 43 days of operation. Metals were also determined in the sulfur extracts. Co and Ni predominated in their oxidizable bonding forms, which increased together with the pseudo-total content during reactor operation. An omission of Co and Ni from the influent led to only a minor decline of the pseudo-total content in the sludge, mainly from the acid-soluble fraction. The ratio of simultaneously extracted metals (Co, Fe, Mn, Ni) to acid-volatile sulfides was lower than 1, indicating that the sludge contained sufficient sulfide to bind the metals as metal monosulfides. The bioavailability of metals in the methanol-grown anaerobic granular sludge investigated is therefore mainly controlled by sulfide formation/dissolution. [source] Use of a bench-top photochemical reactor and solid-phase microextraction to measure semivolatile organic compound-hydroxyl radical rate constantsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2000Mary Jo Bernhard Abstract It is increasingly important to be able to measure semivolatile organic compound-hydroxyl (SOC-OH) radical rate constants and estimate semivolatile organic compounds' (SOCs) atmospheric half-lives because of potential for atmospheric long-range transport. We have used a bench-top photochemical reactor, along with solid-phase microextraction (SPME) and ethyl nitrite, to successfully measure the rate constants of naphthalene, linalool, biphenyl, and phenanthrene with hydroxyl (OH) radical. Biphenyl and phenanthrene underwent wall loss in the reactor. The wall loss rates were determined and were used to correct the measured gas-phase rate constants. The reaction rate constants for naphthalene, linalool, biphenyl, and phenanthrene with OH radical, in our bench-top system at 295 ± 3 K, were determined to be 2.73 ± 0.37 × 10,11, 1.93 ± 0.24 × 10,10, 7.44 ± 1.9 × 10,12, 1.73 ± 0.21 × 10,11 (cm3/molecule/s), respectively, and were in excellent agreement with previous studies and model predictions. Based on the range of experimental and predicted rate constants for these reactants and an estimated average OH concentration in the atmosphere, the atmospheric half-lives of these SOCs are significantly less than 2 d. This indicates that the global presence of these compounds in the atmosphere is primarily due to regional sources and not to atmospheric long-range transport. This study shows that bench-top reactors, combined with corrections for reactant wall loss and simplified analytical tools (such as solid-phase microextraction), can be used to measure SOC-OH rate constants. [source] Excessive production of tumor necrosis factor-alpha by bone marrow T lymphocytes is essential in causing bone marrow failure in patients with aplastic anemiaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 1 2004Takeshi Hara Abstract:, Aplastic anemia (AA) is regarded as an immunological disorder because of the clinical effect of immunosuppressive therapy. Recent studies have reported that cytokines play an important role in the development of AA. In the present study, we measured levels of T-cell derived intracellular cytokine production in peripheral blood and bone marrow (BM) of patients with AA. We demonstrated that BM lymphocytes, particularly CD4+ and CD8+ T cells, in patients with AA produced significantly higher amounts of tumor necrosis factor-alpha (TNF- ,), compared with lymphocytes in normal controls. We have previously reported that expression of TNF receptor (R)1 and TNFR2 in the CD34+ CD38, and CD34+ CD38+ fractions of patients with AA is significantly higher than those in normal control. These results indicate that BM stem cells in patients with AA may possess high sensitivity to TNF- ,. This in turn suggests that TNF- , affects hematopoiesis at an earlier stage in AA patients than in normal controls. We strongly support the hypothesis that a simultaneous increase in TNF- , production by BM lymphocytes and sensitivity of stem cells to TNF- , leads to BM failure in AA. [source] EPR Insensitivity of the Metal-Nitrosyl Spin-Bearing Moiety in Complexes [LnRuII -NO·]kEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 14 2004Stéphanie Frantz Abstract A survey of 18 paramagnetic species [LnRu(NO)]k, including seven new examples studied by in situ electrolysis, reveals a surprisingly narrow range of EPR parameters despite a wide variety of ligands such as pyridine, polypyridines, imines, amines, nitriles, phosphanes, carbonyl, cyclopentadienides, halides, hydride, hydroxide, thiocyanate or cyanide: g1 = 2.015 ± 0.02, g2 = 1.990 ± 0.015, g3 = 1.892 ± 0.03, gav = 1.968 ± 0.02, ,g = g1 , g3 = 0.122 ± 0.037, A2(14N) = 3.3 ± 0.5 mT. This rather small variability, smaller still if the organometallic compounds are excluded, differs from the wider range of EPR data reported for nitrosyliron species with S = 1/2; apparently, the {RuNO}7 configuration involves a rather invariant and relatively covalent metal,NO interaction. DFT calculations were employed for [(NC)5Ru(NO)]3, to reproduce the EPR data, to evaluate the spin distribution (58% spin density on NO), and to reveal structural changes on reduction such as the Ru,N,O bending and Ru,NO bond lengthening. In addition, the possibility of staggered and eclipsed conformations is discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] In search of stable soil organic carbon fractions: a comparison of methods applied to soils labelled with 14C for 40 days or 40 yearsEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 2 2008S. Bruun Summary A reliable method for the isolation of a stable fraction of soil organic carbon (SOC) would be very helpful for improving our understanding of the mechanisms responsible for stabilization of SOC and the dynamics of SOC turnover. We tested acid hydrolysis, physical fractionation (particle density/size), photo-oxidation, treatment with chemical oxidants (NaOCl and NaS2O8) and thermal treatment on two soils incubated with 14C-labelled barley straw for either 40 days or 40 years. Different intensities of the treatments were included. Acid hydrolysis, photo-oxidation and treatment with a chemical oxidant consistently removed more 40-year-old C than 40-day-old C, which suggests that the isolated fractions contained a large proportion of material with a relatively rapid turnover. The clay + silt associated SOC fraction contained a small proportion of 40-day-old C and a large proportion of 40-year-old C. This is consistent with a SOC fraction with medium turnover. The thermal treatment removed more 40-year-old C than 40-day-old C. At 400°C there was still a small proportion of the 40-year-old C remaining, whereas almost all the 40-day-old C was removed. This is consistent with a stable SOC fraction. However, because only 2,3% of the C remained after this treatment, the isolated SOC fraction may be of little quantitative importance. Furthermore, the thermally resistant fraction is likely to be heavily altered by the treatment, and therefore unsuitable for further studies of the chemical nature of stable SOC. [source] Mineral surfaces and soil organic matterEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 2 2003K. Kaiser Summary The organic carbon content of soil is positively related to the specific surface area (SSA), but large amounts of organic matter in soil result in reduced SSA as determined by applying the Brunauer,Emmett,Teller (BET) equation to the adsorption of N2. To elucidate some of the controlling mechanisms of this relation, we determined the SSA and the enthalpy of N2 adsorption of separates with a density > 1.6 g cm,3 from 196 mineral horizons of forest soils before and after removal of organic matter with NaOCl. Likewise, we investigated these characteristics before and after sorption of increasing amounts of organic matter to four mineral soil samples, oxides (amorphous Al(OH)3, gibbsite, ferrihydrite, goethite, haematite), and phyllosilicates (kaolinite, illite). Sorption of organic matter reduced the SSA, depending on the amount sorbed and the type of mineral. The reduction in SSA decreased at larger organic matter loadings. The SSA of the mineral soils was positively related to the content of Fe oxyhydroxides and negatively related to the content of organic C. The strong reduction in SSA at small loadings was due primarily to the decrease in the micropores to which N2 was accessible. This suggests preferential sorption of organic matter at reactive sites in or at the mouths of micropores during the initial sorption and attachment to less reactive sites at increasing loadings. The exponential decrease of the heat of gas adsorption with the surface loading points also to a filling or clogging of micropores at early stages of organic matter accumulation. Desorption induced a small recovery of the total SSA but not of the micropore surface area. Destruction of organic matter increased the SSA of all soil samples. The SSA of the uncovered mineral matrix related strongly to the amounts of Fe oxyhydroxides and the clay. Normalized to C removed, the increase in SSA was small in topsoils and illuvial horizons of Podzols rich in C and large for the subsoils containing little C. This suggests that micropores preferentially associate with organic matter, especially at small loadings. The coverage of the surface of the soil mineral matrix as calculated from the SSA before and after destruction of organic matter was correlated only with depth, and the relation appeared to be linear. We conclude that mineralogy is the primary control of the relation between surface area and sorption of organic matter within same soil compartments (i.e. horizons). But at the scale of complete profiles, the surface accumulation and stabilization of organic matter is additionally determined by its input. [source] Crystal structure of highly thermostable glycerol kinase from a hyperthermophilic archaeon in a dimeric formFEBS JOURNAL, Issue 10 2008Yuichi Koga The crystal structure of glycerol kinase from the hyperthermophilic archaeon Thermococcus kodakaraensis (Tk-GK) in a dimeric form was determined at a resolution of 2.4 Å. This is the first crystal structure of a hyperthermophilic glycerol kinase. The overall structure of the Tk-GK dimer is very similar to that of the Escherichia coli glycerol kinase (Ec-GK) dimer. However, two dimers of Ec-GK can associate into a tetramer with a twofold axis, whereas those of Tk-GK cannot. This may be the reason why Tk-GK is not inhibited by fructose 1,6-bisphosphate, because the fructose 1,6-bisphosphate binding site is produced only when a tetrameric structure is formed. Differential scanning calorimetry analyses indicate that Tk-GK is a highly thermostable protein with a melting temperature (Tm) of 105.4 °C for the major transition. This value is higher than that of Ec-GK by 34.1 °C. Comparison of the crystal structures of Tk-GK and Ec-GK indicate that there is a marked difference in the number of ion pairs in the ,16 helix. Four ion pairs, termed IP1,IP4, are formed in this helix in the Tk-GK structure. To examine whether these ion pairs contribute to the stabilization of Tk-GK, four Tk-GK and four Ec-GK derivatives with reciprocal mutations at the IP1,IP4 sites were constructed. The determination of their stabilities indicates that the removal of each ion pair does not affect the stability of Tk-GK significantly, whereas the mutations designed to introduce one of these ion pairs stabilize or destabilize Ec-GK considerably. These results suggest that the ion pairs in the ,16 helix contribute to the stabilization of Tk-GK in a cooperative manner. [source] A cryptic lysis gene near the start of the Q, replicase gene in the +1 frameGENES TO CELLS, Issue 10 2004Tohru Nishihara The maturation/lysis (A2) protein encoded by the group B single-stranded RNA bacteriophage Q, mediates lysis of host Escherichia coli cells. We found a frameshift mutation in the replicase (,-subunit) gene of Q, cDNA causes cell lysis. The mutant has a single base deletion 73 nucleotides (nt) 3, from the start of the replicase gene with consequent translation termination at a stop codon 129,131 nt further 3,. The 43-amino acid C-terminal part of the 67-amino acid product encoded by what in WT (wild-type) is the +1 frame, is rich in basic amino acids This 67-aa protein can mediate cell lysis whose characteristics indicate that the protein may cause lysis by a different mechanism and via a different target, than that caused by the A2 maturation/lysis protein. Synthesis of a counterpart of the newly discovered lysis product in wild-type phage infection would require a hypothetical ribosomal frameshifting event. The lysis gene of group A RNA phages is also short, 75 codons in MS2, and partially overlaps the first part of their equivalently located replicase gene, raising significant evolutionary implications for the present finding. [source] THE EASTERN MARGIN OF GLACIATION IN THE BRITISH ISLES DURING THE YOUNGER DRYAS: THE BIZZLE CIRQUE, SOUTHERN SCOTLANDGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2006STEPHAN HARRISON ABSTRACT. Geomorphological and sedimentological evidence of former glaciation in the Bizzle valley in the Cheviot Hills of northern England and southern Scotland was used to reconstruct the dimensions of a small topographically constrained glacier with an equilibrium line altitude (ELA) of 535 m. This was interpreted as having formed during Younger Dryas cooling; this is the only glacier to have been described from the area and is the most easterly site of Younger Dryas glaciation in the British Isles. Whilst glaciation at this time was extensive in the Lake District to the southwest, the restricted nature of Cheviot ice cover suggests that a steep west,east precipitation gradient existed in this region during the Younger Dryas. [source] Triassic metasedimentary successions across the boundary between the southern Apennines and the Calabrian Arc (northern Calabria, Italy)GEOLOGICAL JOURNAL, Issue 2 2005A. Iannace Abstract The boundary area between the Apenninic fold-and-thrust belt and the crystalline Calabrian Arc, located around Sangineto in northern Calabria, has been investigated. New geological mapping in the Sant'Agata area has been performed on the Triassic successions traditionally attributed to the metasedimentary San Donato Unit. This, coupled with a reappraisal of the stratigraphy and tectonics of coeval successions present more to the south in the Cetraro Unit, results in a new reconstruction of the Triassic evolution of all the metasedimentary successions found in the region. Four informal stratigraphic units have been distinguished in the S. Agata area. The lowest one (Unit A) consists of well-bedded metalimestones and bioturbated marly limestones that correlate with Ladinian,Carnian carbonates in nearby areas. A second unit (Unit B), never recognized before, contains a complex alternation of dolomites, phyllites and some meta-arenites containing several beds of Cavernoso facies, attributed to the Carnian. They grade upward to platform and platform-margin dolomites of Norian,Rhaetian age (Unit C) that in turn are replaced upward and laterally by a fourth unit (Unit D) consisting of well-bedded, dark dolomites and metalimestones with marly interlayers locally found as resedimented large blocks in slope conglomerates. Unit D correlates with Rhaetian,Liassic beds in nearby areas. Several pieces of evidence of post-metamorphic contractional tectonics, with 140°N and 30°N trends, are found together with evidence of SW-directed extension. The siliciclastic Carnian beds of Unit B are correlated with the phyllites of Cetraro, formerly believed to be Middle Triassic; moreover, it is suggested that in the Cetraro area Unit C is almost totally replaced by Unit D. This demonstrates that the former distinction between the two tectonic units in the whole area has to be discarded. We have made a general palaeoenvironmental reconstruction which progresses laterally, during Ladinian,Carnian times, from (i) a coastal, mixed siliciclastic,carbonate,evaporitic area at Cetraro to (ii) a transitional carbonate shelf where siliciclastic input was only episodic, and finally to (iii) a bioconstructed margin which was later replaced by a steepened margin created by tectonic instability. Starting from the Norian, subsidence shifted toward the former coastal area where an intraplatform, restricted basin developed. The proposed stratigraphy corresponds closely to the Alpujarride units of the Betic Cordillera, Spain. Moreover, it is shown that strong affinities also exist, in terms of the structural framework, with the metamorphic units of Tuscany and Liguria. Copyright © 2005 John Wiley & Sons, Ltd. [source] Carrier testing in haemophilia A and B: adult carriers' and their partners' experiences and their views on the testing of young femalesHAEMOPHILIA, Issue 3 2008N. F. DUNN Summary., This is a descriptive study, which aims to report adult carriers' and their husbands/partners' experiences of carrier diagnosis and their views as to how these issues should be handled for the next generation. Following an initial pilot, 105 carriers and husbands/partners responded to a postal questionnaire. Most of the adult carriers had been tested because either they or their parents wanted to know their carrier status or they had a son diagnosed with haemophilia. The respondents agreed that the main reasons for testing young potential carriers should be either a family history of severe haemophilia or that the young person or her parents wanted to know her status. Forty per cent (35/87) believed the earliest age for carrier testing should be 0,9 years, 44% (38/87) 10,15 years and 16% (14/87) ,16 years. Respondents aged 18,39 years were more likely to be in favour of testing <2 years. If parents and teenagers disagreed, the majority of parents thought that a test should not be forced, consent refused or results withheld. Genetic counselling provides an important opportunity for parents, who want a very early genetic test, to explore their motivations and balance their desire to prepare and protect their daughter with her right to decide as a teenager. [source] Research Submission: Chronic Headache and Comorbibities: A Two-Phase, Population-Based, Cross-Sectional StudyHEADACHE, Issue 8 2010Ariovaldo Da Silva Jr MD Background., Studies using resources of a public family health program to estimate the prevalence of chronic daily headaches (CDH) are lacking. Objectives., To estimate the 1-year prevalence of CDH, as well as the presence of associated psychiatric and temporomandibular disorders (TMD) comorbidities, on the entire population of a city representative of the rural area of Brazil. Methods., This was a cross-sectional, population-based, 2-phase study. In the first phase, health agents interviewed all individuals older than 10 years, in a rural area of Brazil. In the second stage, all individuals who reported headaches on 4 or more days per week were then evaluated by a multidisciplinary team. CDH were classified according to the second edition of the International Classification of Headache Disorders (ICHD-2). Medication overuse headache was diagnosed, as per the ICHD-2, after detoxification trials. Psychiatric comorbidities and TMD were diagnosed based on the DSM-IV and on the Research Diagnostic Criteria for Temporomandibular Disorders criteria, respectively. Results., A total of 1631 subjects participated in the direct interviews. Of them, 57 (3.6%) had CDH. Chronic migraine was the most common of the CDH (21, 36.8%). Chronic tension-type headache (10, 17.5%), medication overuse headache (13, 22.8%) and probable medication overuse headache (10, 17.5%) were also common. Psychiatric disorders were observed in 38 (67.3%) of the CDH subjects. TMD were seen in 33 (58.1)% of them. Conclusions., The prevalence of CDH in the rural area of Brazil is similar to what has been reported in previous studies. A significant proportion of them have psychiatric comorbidities and/or TMD. In this sample, comorbidities were as frequent as reported in convenience samples from tertiary headache centers. (Headache 2010;50:1306-1312) [source] Endonasal Endoscopic Management of Contact Point Headache and Diagnostic CriteriaHEADACHE, Issue 2 2010Alireza Mohebbi MD (Headache 2010;50:242-248) Background., Some types of headaches with sinonasal origin may be present in the absence of inflammation and infection. The contact points between the lateral nasal wall and the septum could be the cause of triggering and sustained pain via trigeminovascular system. Objective., The aim of this study was to evaluate the feasibility and effectiveness of endoscopic surgery in the sinonasal region for treatment of headache with special attention paid to specific diagnostic methods and patient selection. Methods., This was a prospective, non-randomized and semi-quasi experimental research study. Thirty-six patients with chronic headaches who had not previously responded to conventional treatments were evaluated by rhinoscopy and/or endoscopy, local anesthetic tests and computed tomography scans as diagnostic criteria. These patients were divided into 4 groups based on the diagnostic methods utilized. The intensity of headaches pre- and post-operatively were recorded by utilizing the visual analog scale scale and performing analysis with analysis of variance test comparison and Statistical Package for Social Sciences. Average follow-up was 30 months. Results., Our overall success rate approximated 83% while the complete cure rate was 11%. Patients in group 4 achieved the best results. In this group all diagnostic criteria were positive. In addition, patient responses were statistically significant in groups with more than one positive criteria compared with group 1 who only had positive examination. The positive response of 14 migrainous patients diagnosed with migraine prior to treatment was 64%. Conclusion., Surgery in specific cases of headaches with more positive evidence of contact point could be successful, particularly if medical therapy has failed. [source] Divalproex Sodium Extended-Release for the Prophylaxis of Migraine Headache in Adolescents: Results of a Stand-Alone, Long-Term Open-Label Safety StudyHEADACHE, Issue 1 2009George Apostol MD Objective., The objective of this long-term open-label study in adolescents was to assess the safety and tolerability of divalproex sodium extended-release in the prophylaxis of migraine headaches. Background., Two formulations of divalproex sodium have demonstrated efficacy in the prevention of migraine headaches in adults. However, no medications are currently approved for this indication in adolescents, and long-term safety data on agents for migraine prevention are lacking for this younger population. Therefore, the current study was conducted to assess the long-term safety and tolerability of divalproex extended-release in adolescents with migraine headaches. Methods., This was a 12-month, phase 3, open-label, multicenter study of adolescents aged 12 to 17 years with migraine headaches diagnosed by International Headache Society criteria. Divalproex sodium extended-release was initiated at 500 mg/day for 15 days then increased to 1000 mg daily, with subsequent adjustments permitted within a dosing range of 250-1000 mg daily. Study visits were conducted at days 1 and 15 and months 1, 2, 3, 6, 9, and 12. Safety was evaluated by adverse event collection, laboratory assessments, physical and neurological examinations, vital signs, electrocardiograms, the Udvalg for Kliniske Undersøgelser Side Effect Rating Scale, the Wechsler Abbreviated Scale of Intelligence, and the Behavioral Assessment Scale for Children. Efficacy was evaluated by following the number of migraine headache days reported in subjects' headache diaries over sequential 4-week intervals for the duration of the trial. Results., A total of 241 subjects were enrolled and treated. The most frequently reported adverse events were nausea (19%), vomiting (18%), weight gain (12%), nasopharyngitis (11%), migraine (10%), and upper respiratory tract infection (10%). Ten (4%) subjects experienced serious adverse events, and 40 (17%) subjects discontinued because of an adverse event. Increases in ammonia levels were observed. No other clinically significant changes were observed in laboratory values, vital signs, rating scales, or electrocardiograms. Median 4-week migraine headache days decreased 75% between the first and the fourth months of the study (from 4.0 to 1.0) and remained at or below this level for the remainder of the study. Conclusions., In this long-term open-label study of adolescents with migraine, the safety and tolerability profile of divalproex sodium extended-release was consistent with findings from previous trials in adults, as well as 2 studies recently completed in adolescents. In general, divalproex sodium extended-release was well-tolerated in adolescents with migraine. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||