Home About us Contact
|
Home About us Contact | ||
|
|
||
DT
Selected AbstractsMitigation of Electromagnetic Instabilities in Fast Ignition ScenarioCONTRIBUTIONS TO PLASMA PHYSICS, Issue 3-4 2005C. Deutsch Abstract We address the issues of collective stopping for intense relativistic electron beams (REB) used to selectively ignite precompressed deuterium + tritium (DT) fuels. We investigate the subtle interplay of electron collisions in target as well as in beam plasmas with quasi-linear electromagnetic growth rates. Intrabeam scattering is found effective in taming those instabilities, in particular for high transverse temperatures. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Digestive tract ontogeny of Dicentrarchus labrax: Implication in osmoregulationDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 3 2006Ivone Giffard-Mena The ontogeny of the digestive tract (DT) and of Na+/K+ -ATPase localization was investigated during the early postembryonic development (from yolk sac larva to juvenile) of the euryhaline teleost Dicentrarchus labrax reared at two salinities: seawater and diluted seawater. Histology, electron microscopy and immunocytochemistry were used to determine the presence and differentiation of ion transporting cells. At hatching, the DT is an undifferentiated straight tube over the yolk sac. At the mouth opening (day 5), it comprises six segments: buccopharynx, esophagus, stomach, anterior intestine, posterior intestine and rectum, well differentiated at the juvenile stage (day 72). The enterocytes displayed ultrastructural features similar to those of mitochondria-rich cells known to be involved in active ion transport. At hatching, ion transporting cells lining the intestine and the rectum exhibited a Na+/K+ -ATPase activity which increased mainly after the larva/juvenile (20 mm) metamorphic transition. The immunofluorescence intensity was dependent upon the stage of development of the gut as well as on the histological configuration of the analyzed segment. The appearance and distribution of enteric ionocytes and the implication of the DT in osmoregulation are discussed. [source] Aspiration biopsy cytology of extraabdominal desmoid tumor concurrently occurring in a patient with tumoral calcinosisDIAGNOSTIC CYTOPATHOLOGY, Issue 9 2008F.I.A.C., Husain Saleh M.D., M.B.A. Abstract Extraabdominal fibromatosis or desmoid tumor (DT) is a slow growing locally aggressive soft tissue tumor that can occur anywhere in the body. We report the aspiration biopsy cytology features of a case of DT of the right neck area in a 35-year-old man who had a long standing history of tumoral calcinosis. The aspirate was interpreted as "benign spindle cell lesion" and confirmed as DT on histologic examination of the resected mass. We discuss the possible differential diagnoses of other benign or malignant lesions on fine-needle aspiration (FNA) biopsy and especially discuss the aspiration cytology features of DT compared with those of tumoral calcinosis. We also discuss the value of immunohistochemical markers that help in differentiating DT from other entities. Diagn. Cytopathol. 2008;36:624,627. © 2008 Wiley-Liss, Inc. [source] Xanthine-analog, KMUP-2, enhances cyclic GMP and K+ channel activities in rabbit aorta and corpus cavernosum with associated penile erectionDRUG DEVELOPMENT RESEARCH, Issue 3 2002Rong-Jyh Lin Abstract The pharmacological properties of KMUP-2 were examined in isolated rabbit aorta and corpus cavernosum smooth muscle (CCSM). KMUP-2 caused relaxations that were attenuated by removed endothelium, high K+, and pretreatment with the soluble guanylate cyclase (sGC) inhibitors methylene blue (10 ,M) and ODQ (1 ,M), a NOS inhibitor, L-NAME (100 ,M), a K+ channel blocker TEA (10 mM), a KATP channel blocker glibenclamide (1 ,M), a voltage-dependent K+ channel blocker 4-AP (100 ,M), and the Ca2+ -dependent K+ channel blockers apamin (1 ,M) and charybdotoxin (ChTX, 0.1 ,M). The relaxant responses of KMUP-2 (0.01, 0.05, 0.1 ,M) together with a PDE inhibitor, IBMX (0.5 ,M), had additive effects on rabbit aorta and CCSM. Additionally, KMUP-2 (100 ,M) also affected cGMP metabolism, due to its inhibiting activity on PDE in human platelets. KMUP-2 (0.1,100 ,M) further induced an increase of intracellular cGMP levels in the primary cultured rabbit aortic and CCSM cells. These increases in cGMP content were abolished in the presence of methylene blue (100 ,M) and ODQ (10 ,M). Obviously, the relaxant effects of KMUP-2 on rabbit isolated tissues are more sensitive in CCSM than in aorta. Moreover, KMUP-2 also stimulated NO/sGC/cGMP pathway and subsequent elevation of cGMP by blockade of PDE and enhanced opening of K+ channels in rabbit aorta and CCSM. KMUP-2 (0.2, 0.4, 0.6 mg/kg), similar to KMUP-1 and sildenafil, caused increases of intracavernous pressure (ICP) and duration of tumescene (DT) in a dose-dependent manner. It is concluded that both the increases of cGMP and the opening activity of K+ channels play prominent roles in KMUP-2-induced aortic smooth muscle and CCSM relaxation and increases of ICP in rabbits. Drug Dev. Res. 55:162,172, 2002. © 2002 Wiley-Liss, Inc. [source] Dipole Tracing Examination for the Electric Source of Photoparoxysmal Response Provoked by Half-Field StimulationEPILEPSIA, Issue 2000Kazuhiko Kobayashi Purpose: Dipole tracing (DT) is a computer-aidcd noninvasive method used to estimate the location of epileptic discharges from the scalp EEG. In DT equivalent current dipoles (ECDs), which rcflcct the electric source in the brain, are rcsponsible for the potential distribution on the scalp EEC. Thercfore, the DT method is useful to estimatc the focal paroxysmal discharges. In this study we examined the location of the clectric source of photoparoxysmal response (PPR) using scalpskull-brain dipolc tracing (SSB-DT) after hal[-field stimulation, which produced focal PPR on the scalp EEG. Methods: We studied 4 cases of photoscnsitive epilepsy. Wc performed 20 Hz red flicker and flickcring dot pattern half-ficld stimulation to provoke PPR. In this method, the loci of gcnerators corresponding to the paroxysmal discharges were estimated as ECDs by I - and 2-dipole analyses. Each location of the ECDs was estimated by iterative calculation. Algorithms minimizing the squarcd difference betwccn the electrical potentials recorded from the scalp EEG and those calculated theoretically from the voluntary dipoles were uscd. In the SSB model, the scalp shell was reconstructed from the helmet mcasurements, and the shapc of the skull and brain was 3-dimcnsionally reconstructed from CT images. A dipolarity larger than 98% w the accuracy of the estimation. We recorded thcir 2 I channel monopolar scalp EEG. Each spike was sampled analyzed at 10 points around the peaks of at least 10 spikes in each patient using the SSB-DT method. The ECDs were then supcrimposed on thc MRI of each palient to idcntify the more cxact anatomical region. Results: This study showed the location of cach focus and a dipolarity of greater than 98% in all cases, although the results from the 2-dipole method showed scattered location. We considered that the analyzed signals were generated from single source. PPR was elicitcd cross-lateral to the field stimulated. By red flicker half-field stimulation, EEG revealed eithcr focal spikes and waves in the contralatcral occipital, temporo-occipitel region, or diffuse spikes and wave complex bursts, sccn dominantly at the contralateral hcmisphere. The supcrimposed ESDs on MRI were located at the occipital or inferior temporal lobe. PPR, provoked by flickering dot pattern half-field stimulation, werc focal spikes and waves, mainly in the occipital, parieto-occipital region, or diffuse spikes and wave complcx bursts, seen dominantly at thc contralateral hcmiaphere. The ECDs of their PPRs were located in the occipital, inferior temporal, or inferior pirietal lobules on MRI. Conclusion: Our findings suggest that the inferior temporal and inferior parictal lobules which are important for the processing sequence of the visual system in addition to the occipital lobc, might he responsible for thc mechanism of PPR by half-ficld stimulation, espccially for electric source expansion. [source] GENETIC STUDY: Interaction of SLC6A4 and DRD2 polymorphisms is associated with a history of delirium tremensADDICTION BIOLOGY, Issue 1 2010Victor M. Karpyak ABSTRACT Several genetic polymorphisms have been reported to be associated with alcohol withdrawal seizures (AWS) and delirium tremens (DT). To replicate and further explore these findings, we investigated the effects of 12 previously reported candidate genetic variations in two groups of alcohol-dependent European Americans with a history of withdrawal, which differed according to the presence (n = 112) or absence (n = 92) of AWS and/or DT. Associations of AWS and/or DT with the genomic and clinical characteristics and gene,gene interaction effects were investigated using logistic regression models. None of the polymorphisms were significantly associated with AWS/DT after correction for multiple testing. However, we found a significant interaction effect of the SLC6A4 promoter polymorphism (5-HTTLPR) and DRD2 exon 8 single nucleotide polymorphism rs6276 on AWS and/or DT history (P = 0.009), which became more significant after adjustment for lifetime maximum number of drinks consumed per 24 hours (P < 0.001). Subsequent analysis revealed an even stronger association of the SLC6A4,DRD2 interaction with DT (P < 0.0001), which remained significant after Bonferroni correction. Results reveal decreased likelihood of DT in alcoholics that carry the DRD2 rs6276 G allele and SLC6A4 LL genotype. This study provides the first evidence to implicate the interaction between serotonin and dopamine neurotransmission in the etiology of DT. Replication is necessary to verify this potentially important finding. [source] Derivation of Recovery Kinetics From Stress Relaxation Tests,ADVANCED ENGINEERING MATERIALS, Issue 3 2010Sheila Bhaumik The recovery behavior of a commercial aluminum alloy 3103 was investigated by the means of two alternative experimental methods: stress relaxation (SR) and double tension tests (DT). In case of SR, the stress,time evolution after deformation was recorded, and for DT the yield stress after several recovery times were measured. The DT tests were further sub-divided into tests with and without external load during recovery. The results revealed that the recovery kinetics is clearly accelerated by the external stress during the SR. However, the difference between the DT and SR stresses is much larger. It is caused by continued dislocation glide after the deformation, which causes continued plastic elongation of the specimens. This is demonstrated quantitatively by appropriate evaluation models for both experiments. In contrast to DT, the SR evaluation accounts for the elastic SR due to plastic elongation, but the recovery parameters are the same ones as for DT. This makes it possible to replace DT by SR experiments, which are materially less laborious. [source] Caries and dental fluorosis in a western Saharan population of refugee childrenEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2008José Manuel Almerich-Silla The aim of this study was to investigate the relationship between dental fluorosis and dental caries among western Saharan refugee children. The western Saharan child population is characterized by adverse living conditions, an unbalanced diet, poor oral hygiene habits, and a concentration of fluoride in the drinking water of around 2 p.p.m. (2 mg l,1). A sample consisting of 360 children, 6,7 yr of age, and 212 children, 11,13 yr of age, was obtained from four refugee camps (Smara, Awsard, El-Aaiun, and 27-February) situated in the vicinity of Tindouf (southern Algeria). The children were examined using the World Health Organization criteria for caries diagnosis and Dean's index for fluorosis. The decayed, missing or filled teeth (DMFT) score was 0.48 in the 6,7-yr-old children and 1.69 in the 11,13-yr-old children, with a caries prevalence (DMFT > 0 or decayed and filled primary teeth (dft) > 0) of 47.2% and 63.2%, respectively. Among the 6,7 yr-old children examined, 36.9% were free of fluorosis, 15.6% presented moderate fluorosis, and 7.8% presented severe fluorosis. Among 11,13 yr-old children, only 4.2% were free of fluorosis, 30.2% exhibited moderate fluorosis, and 27.4% presented severe fluorosis. The mean DMFT, decayed permanent teeth (DT), and caries prevalence (DMFT > 0 and DMFT or dft > 0) scores were significantly higher among the children affected by severe fluorosis, suggesting that severe fluorosis might increase the susceptibility to dental caries. [source] Thirty years on from the paper ,Gust Spectrum Fatigue Crack Propagation in Candidate Skin Materials', Fatigue of Engineering Materials and Structures, Vol.FATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 1 2009IMPACT OF THE PAPER This paper1 addressed a very specific topic and by itself would not have had much impact in the intervening years. However, most of the paper's content was subsequently included in an extensive report on the Damage Tolerance (DT) properties of aluminium alloys.2 This report enabled guidelines for flight simulation fatigue crack growth testing to be formulated.3,4 [source] Genotypes of multidrug-resistant Salmonella enterica serotype typhimurium from two regions of KenyaFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2000Samuel Kariuki Abstract A combination of phage typing and pulsed-field gel electrophoresis of XbaI-digested chromosomal DNA has been used to study the epidemiological relationships of multidrug-resistant Salmonella enterica serotype typhimurium from Nairobi (64 isolates) and Kilifi (40 isolates) collected over the period 1994,1997. Isolates from Nairobi belonged to 11 definitive phage types (DTs) encompassing eight different PFGE patterns. In contrast, isolates from Kilifi were mainly DT 56 (60%) and all fell into a single PFGE pattern. The remaining isolates did not conform to a recognisable phage type. We conclude that multidrug-resistant S. typhimurium infections from Nairobi were caused by multiple strains while those from Kilifi were likely to be from a microepidemic caused by a single clone. [source] Sensorimotor network rewiring in mild cognitive impairment and Alzheimer's diseaseHUMAN BRAIN MAPPING, Issue 4 2010Federica Agosta Abstract This study aimed at elucidating whether (a) brain areas associated with motor function show a change in functional magnetic resonance imaging (fMRI) signal in amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD), (b) such change is linear over the course of the disease, and (c) fMRI changes in aMCI and AD are driven by hippocampal atrophy, or, conversely, reflect a nonspecific neuronal network rewiring generically associated to brain tissue damage. FMRI during the performance of a simple motor task with the dominant right-hand, and structural MRI (i.e., dual-echo, 3D T1-weighted, and diffusion tensor [DT] MRI sequences) were acquired from 10 AD patients, 15 aMCI patients, and 11 healthy controls. During the simple-motor task, aMCI patients had decreased recruitment of the left (L) inferior frontal gyrus compared to controls, while they showed increased recruitment of L postcentral gyrus and head of L caudate nucleus, and decreased activation of the cingulum compared with AD patients. Effective connectivity was altered between primary sensorimotor cortices (SMC) in aMCI patients vs. controls, and between L SMC, head of L caudate nucleus, and cingulum in AD vs. aMCI patients. Altered fMRI activations and connections were correlated with the hippocampal atrophy in aMCI and with the overall GM microstructural damage in AD. Motor-associated functional cortical changes in aMCI and AD mirror fMRI changes of the cognitive network, suggesting the occurrence of a widespread brain rewiring with increasing structural damage rather than a specific response of cognitive network. Hum Brain Mapp, 2010. © 2009 Wiley-Liss, Inc. [source] A multiparametric evaluation of regional brain damage in patients with primary progressive multiple sclerosisHUMAN BRAIN MAPPING, Issue 9 2009Antonia Ceccarelli Abstract The purpose of this study is to define the topographical distribution of gray matter (GM) and white matter (WM) damage in patients with primary progressive multiple sclerosis (PPMS), using a multiparametric MR-based approach. Using a 3 Tesla scanner, dual-echo, 3D fast-field echo (FFE), and diffusion tensor (DT) MRI scans were acquired from 18 PPMS patients and 17 matched healthy volunteers. An optimized voxel-based (VB) analysis was used to investigate the patterns of regional GM density changes and to quantify GM and WM diffusivity alterations of the entire brain. In PPMS patients, GM atrophy was found in the thalami and the right insula, while mean diffusivity (MD) changes involved several cortical-subcortical structures in all cerebral lobes and the cerebellum. An overlap between decreased WM fractional anisotropy (FA) and increased WM MD was found in the corpus callosum, the cingulate gyrus, the left short temporal fibers, the right short frontal fibers, the optic radiations, and the middle cerebellar peduncles. Selective MD increase, not associated with FA decrease, was found in the internal capsules, the corticospinal tracts, the superior longitudinal fasciculi, the fronto-occipital fasciculi, and the right cerebral peduncle. A discrepancy was found between regional WM diffusivity changes and focal lesions because several areas had DT MRI abnormalities but did not harbor T2-visible lesions. Our study allowed to detect tissue damage in brain areas associated with motor and cognitive functions, which are known to be impaired in PPMS patients. Combining regional measures derived from different MR modalities may be a valuable tool to improve our understanding of PPMS pathophysiology. Hum Brain Mapp 2009. © 2009 Wiley-Liss, Inc. [source] Three phosphor plate systems and film compared for imaging root canalsINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2001A. C. Shearer Abstract Aim The aim of this study was to compare three phosphor plate intraoral imaging systems (Digora (DA), Digident (DT), Denoptix (DX)) and E-speed conventional film (CF) for the imaging of root canals. Methodology Sixty extracted permanent teeth were exposed using CF, DA, DT and DX. The length of root canal visible from its most apical extent to a line drawn at the level of the cementoenamel junction was measured and this was expressed as a percentage of the distance between the radiographic apex and the cementoenamel line. All images were examined concurrently by two examiners. Films were viewed under standardized conditions and DA, DT and DX images were viewed directly from the monitor screen. The images on the monitor were enhanced to give the subjectively clearest image. Results The mean percentage of canal visible on CF was 90%, DA 78%, DT 81% and DX 83%. The difference was significant for CF,DA (P < 0.001) and CF,DT (P = 0.001). There was no statistically significant difference for CF,DX or between any of the three phosphor plate imaging systems. Conclusions It is concluded that a greater length of root canal was visible on conventional film than on three phosphor plate imaging systems and that this may be of clinical significance. [source] A binary-based on-chip CNN solution for pixel-level snakesINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 4 2006V. M. Brea Abstract This paper introduces a binary-based on-chip cellular neural network (CNN) solution for pixel-level snakes. Every cell in the array comprises circuitry for B/W and grey-scale processing. The B/W processing is performed with a positive range high-gain discrete-time (DT)CNN model with 1-bit of programmability. The grey-scale processing is executed on a dedicated sub-cell. The design efforts are mainly focused on area consumption and processing speed. The result is a chip with a resolution of 9 × 9 cells in a 0.18 µm CMOS technology process and a density of more than 700cells/mm2. Simulations at schematic level lead to a time of less than 100ns for every DTCNN step. The peak power dissipation is kept at a few watts in a hypothetical chip of 128 × 128 cells. Copyright © 2006 John Wiley & Sons, Ltd. [source] Body dissatisfaction and drive for thinness in young adult twinsINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 3 2005Anna Keski-Rahkonen MD Abstract Objective We explored correlates of the Eating Disorder Inventory subscales Body Dissatisfaction (BD) and Drive for Thinness (DT) and genetic and environmental influences on these traits. Method In a population-based sample of 4,667 Finnish twins aged 22,27 years, we conducted twin modeling to explore genetic and environmental contributions to body dissatisfaction and drive for thinness. Logistic regression was used for the correlational analysis. Results Various eating and body size-related factors and psychosomatic symptoms were significantly associated with high body dissatisfaction and drive for thinness in both genders. In women, early puberty onset, early initiation of sexual activity, and multiple sex partners were statistically significant risk factors of body dissatisfaction. In gender-specific univariate twin models, additive genes accounted for 59.4% (95% confidence interval [CI] = 53.2,64.7%) of the variance in body dissatisfaction and for 51.0% (95% CI = 43.7,57.5%) of the variance in drive for thinness among females, but for none of the variance among males. Discussion There are very distinct gender differences in the heritability patterns of body dissatisfaction and drive for thinness in young adults. © 2005 by Wiley Periodicals, Inc. [source] DTI-DROID: Diffusion tensor imaging-deformable registration using orientation and intensity descriptorsINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 2 2010Madhura Ingalhalikar Abstract This article presents a method (DROID) for deformable registration of diffusion tensor (DT) images that utilizes the full tensor information by integrating the intensity and orientation features into a hierarchical matching framework. The intensity features are derived from eigen value based measures that characterize the tensor in terms of its different shape properties, such as, prolateness, oblateness, and sphericity of the tensor. Local spatial distributions of the prolate, oblate, and spherical geometry are used to create an attribute vector called the geometric/intensity feature for matching. The orientation features are the orientation histograms computed from the eigenvectors. These intensity and orientation features are incorporated into a hierarchical deformable registration framework to develop a deformable registration algorithm for DT images. Using orientation features improves the matching of the white matter fiber tracts by taking into account the underlying fiber orientation information. Extensive experiments on simulated and real brain DT data show promising results that makes DROID potentially useful for subsequent group-based analysis of DT images to identify disease-induced and developmental changes in a population. © 2010 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 20, 99,107, 2010 [source] Vibrational,rotational energies of all H2 isotopomers using Monte Carlo methodsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 8 2006S. A. Alexander Abstract Using variational Monte Carlo techniques, we have computed several of the lowest rotational,vibrational energies of all the hydrogen molecule isotopomers (H2, HD, HT, D2, DT, and T2). These calculations do not require the excited states to be explicitly orthogonalized. We have examined both the usual Gaussian wave function form as well as a rapidly convergent Padé form. The high-quality potential energy surfaces used in these calculations are taken from our earlier work and include the Born,Oppenheimer energy, the diagonal correction to the Born,Oppenheimer approximation, and the lowest-order relativistic corrections at 24 internuclear points. Our energies are in good agreement with those determined by other methods. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [source] Commentary on Vermeulen H, Ubbink DT, Schreuder SM and Lubbers MJ (2007) Inter- and intra-observer (dis)agreement among nurses and doctors to classify colour and exudation of open surgical wounds according to the Red,Yellow,Black scheme.JOURNAL OF CLINICAL NURSING, Issue 12 2008Journal of Clinical Nursing1, Kitagawa A (2007) A study of the efficiency, Konya C, Matsui Y, Okuwa M, Sanada H, Sugama J, convenience of an advanced portable wound measurement system (VISITRAKTM). [source] Dabska tumor arising in lymphangioma circumscriptumJOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2008Patrick O. Emanuel We describe a case of Dabska tumor (DT) occurring within a large congenital lymphangioma circumscriptum on the thigh of a 14-year-old female. Diagnostic biopsy showed numerous intravascular papillary projections lined by atypical endothelial cells within the anastomosing vascular channels of a lymphangioma circumscriptum. DT is regarded as a vascular tumor of intermediate malignant potential, most probably of lymphatic origin. Although it has been described in pre-existing lymphangiomas, to the best of our knowledge this is the first case to be described in a pre-existing lymphangioma circumscriptum. During a follow-up of 9 years, the lymphangioma circumscriptum has recurred, but there has been no evidence of DT recurrence or metastasis. [source] EFFECT OF SPICES ON GROWTH AND SURVIVAL OF SALMONELLA TYPHIMURIUM DT 104 IN GROUND BEEF STORED AT 4 AND 8CJOURNAL OF FOOD SAFETY, Issue 2 2006MILAGROS UHART ABSTRACT Few studies have addressed the use of spices against pathogens associated with meat. The effects of garlic, ginger and turmeric were evaluated against Salmonella Typhimurium DT 104 that were inoculated either in spice paste or in buffered peptone water (BPW) or in heat-treated ground beef and stored at 4 and 8C for 10 days. Data from the spice pastes study showed a decrease in Salmonella Typhimurium DT 104 counts, and the greatest reduction (3.39 log) was observed in garlic paste stored at 4C. Garlic in BPW data showed a reduction of 1.5 and 1.0 log in Salmonella Typhimurium counts at 4 and 8C, respectively. Ground beef stored at 4C showed no growth or a slight reduction in growth in samples with spice, while all samples at 8C showed an increase in Salmonella Typhimurium counts. Results show that the spices inhibit or inactivate Salmonella Typhimurium DT 104 when they are in direct contact. However, when spices are added to a complex food system such as ground beef, the inhibitory activity of these spices considerably decreases. [source] Impact of Harvesting and Processing Conditions on Green Leaf Volatile Development and Phenolics in Concord Grape JuiceJOURNAL OF FOOD SCIENCE, Issue 3 2010M.M. Iyer ABSTRACT:, The disruption of plant cell walls during fruit juice processing results in the enzymatic formation of herbaceous-smelling green leaf volatiles (GLVs). Our objective was to assess the impact of thermal processing conditions on resulting levels of GLVs (hexanal, trans -2-hexenal, hexanol, cis -3-hexenol, and trans -2-hexenol), total phenols, monomeric anthocyanins, and percent polymeric color in Concord grape juice. The effects of fruit maturity and stage of juice processing on juice GLV content was also assessed. Of the GLVs studied, only trans -2-hexenal routinely exceeded its published sensory threshold in finished juice. We observed an inverse linear correlation between berry maturity (total soluble solids) and trans -2-hexenal levels in finished juice (P,< 0.05, R 2= 0.91). Trans -2-hexenal was at a maximum immediately following crushing (569 ,g/kg, >30-fold over detection threshold [DT]), decreased to 100 ,g/kg following depectinization, pressing, and pasteurization, and to 32 ,g/kg following cold-stabilization. The loss of trans -2-hexenal could be explained primarily by its reduction to trans -2-hexenol, which increased from 53 ,g/kg after crushing to 500 ,g/kg after cold-stabilization. High temperature pretreatment of must immediately following crushing ("hot break") resulted in 5- to 6-fold higher concentrations of trans -2-hexenal in the final bottled juice as compared to conventional hot press. Contrary to expectations, no significant increase in phenolics and anthocyanins were observed in hot break conditions. These results indicate that hot break procedures may thermally inactivate enzymes responsible for transforming trans -2-hexenal under normal processing conditions and potentially alter the flavor qualities of the finished Concord juice. Different equivalent pasteurization regimes (82 to 93 °C) prior to bottling had no significant effect on GLV content of the finished Concord juices (P,> 0.05). Practical Application: Introducing new processing techniques to fruit juice production can potentially result in undesirable changes to organoleptic properties. We have observed significantly higher levels of trans- 2-hexenal, a potent herbaceous off-flavor, in Concord grape juice prepared with an initial high temperature heat treatment ("hot break"). Concord juice producers should be cautious in using hot break processing, especially with immature fruit, as it may result in persistence of green aromas in juice. [source] Determination of Ortho- and Retronasal Detection Thresholds for 2-Isopropyl-3-Methoxypyrazine in WineJOURNAL OF FOOD SCIENCE, Issue 7 2007G.J. Pickering ABSTRACT:, 2-isopropyl-3-methoxypyrazine (IPMP) is a grape-derived component of wine flavor in some wine varieties as well as the causal compound of the off-flavor known as ladybug taint (LBT), which occurs when Harmonia axyridis beetles are incorporated with the grapes during juice and wine processing. The main objective of this study was to obtain robust estimates of the orthonasal (ON) and retronasal (RN) detection thresholds (DTs) for IPMP in wines of differing styles. The ASTM E679 ascending forced choice method of limits was used to determine DTs for 47 individuals in 3 different wines,Chardonnay, Gewürztraminer, and a red wine blend of Baco Noir and Marechel Foch. The group best estimate thresholds (BETs) obtained for IPMP (ng/L) were Chardonnay, ON: 0.32; Gewürztraminer, ON: 1.56, RN: 1.15, and red wine blend, ON: 1.03, RN: 2.29. A large variation in individual DTs was observed. Familiarity with LBT was inversely correlated with DTs for Gewürztraminer, and no difference in thresholds was observed between winemakers and nonwinemakers. We conclude that the human DT for IPMP is extremely low and influenced significantly by wine style and evaluation mode. We recommend against the reporting of single-threshold values for wine flavor compounds, and encourage the determination of consumer rejection thresholds for IPMP in wine. [source] Determination of cardiac involvement in sarcoidosis by magnetic resonance imaging and Doppler echocardiographyJOURNAL OF INTERNAL MEDICINE, Issue 5 2002C. M. Sköld Abstract. Sköld CM, Larsen FF, Rasmussen E, Pehrsson SK, Eklund AG (Karolinska Hospital and Institutet, Stockholm, Sweden). Determination of cardiac involvement in sarcoidosis by magnetic resonance imaging and Doppler echocardiography. J Intern Med 2002; 252: 465,471. Objectives. To elucidate whether cardiac magnetic resonance imaging (MRI) could be useful in disclosing structural changes in the myocardium in sarcoidosis patients and to relate echo-Doppler derived indices of left ventricular function to electrocardiogram (ECG) findings. Design. The MRI was performed in 18 consecutive patients with sarcoidosis. Left ventricular ejection fraction (LVEF), i.e. systolic function, was estimated echocardiographically by Simpson's two-dimensional method (n = 16). Diastolic function was estimated by age-corrected Doppler-derived indices: isovolumetric relaxation time (IVRT), deceleration time (DT) and early filling/atrial contraction ratio (E/A ratio). Results. Eleven patients had conduction defects or dysrhythmias (ECG+) whilst seven patients had a normal ECG (ECG,). In two patients, high signalling, contrast-enhanced, isolated regions, suggestive of deposits, were seen in the left ventricular myocardium on MRI. Both these patients had abnormal ECGs and signs of systolic and/or diastolic dysfunction on echocardiography. LVEF was subnormal in seven of 10 of the ECG+ patients and in two of six of the ECG,. Signs of diastolic dysfunction were found in 59% and 56% of the measurements in the ECG+ and ECG, patients, respectively. Conclusion. We conclude (i) that myocardial deposits on MRI in sarcoidosis patients have a high specificity for cardiac involvement but a rather low sensitivity; (ii) that a substantial proportion of sarcoidosis patients with abnormal ECGs have echocardiographic signs of systolic and/or diastolic dysfunction. [source] Stabilization of alum-adjuvanted vaccine dry powder formulations: Mechanism and applicationJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 2 2003Yuh-Fun Maa Abstract Studies were performed to elucidate the mechanism of alum gel coagulation upon freezing and drying and its relationship to vaccine potency loss and to develop a novel freeze-drying process for the production of stable alum-adjuvanted vaccine formulations suitable for conventional needle injection and epidermal powder immunization (EPI). The alum hydroxide-adjuvanted hepatitis-B surface antigen (Alum-HBsAg) and the alum phosphate-adjuvanted diphtheria and tetanus toxoids (Alum-DT) were dehydrated by freeze drying (FD), spray drying (SD), air drying (AD), or spray freeze drying (SFD). After drying by FD, SD, or AD, alum gels coagulated when examined by optical microscopy and particle size analysis. In addition, desorption of antigen molecules from the coagulated when examined by optical microscopy and particle size analysis. In addition, desorption of antigen molecules from the coagulated alum gel upon reconstitution appeared to be difficult, as indicated by attenuated band intensity on SDS-PAGE. In contrast, SFD alum gels turned a homogenous suspension upon reconstitution, suggesting minimal alum coagulation. In the mouse model, the in vivo immunogenicity of SFD Alum-HBsAg was preserved, whereas the FD Alum-HBsAg suffered significant immunogenicity loss. Grinding of coagulated FD Alum-HBsAg into smaller particles could partially recover the immunogenicity. In a guinea pig study using EPI, the SD Alum-DT formulation was not immunogenic, but the SFD Alum-DT formulations had a vaccine potency comparable to that of the untreated DT administered by I.M. injection. Overall, the relationship of coagulation of alum gel upon reconstitution and the loss of vaccine potency was established in this study. Alum gels became highly coagulated after dehydration by spray drying and traditional freeze-drying processes. However, freezing rate played a critical role in preserving the adjuvant effect of alum and fast freezing decreased the tendency of alum coagulation. Spraying the alum gel into liquid nitrogen represents the fastest freezing rate achievable and resulted in no discernible alum coagulation. Therefore, SFD presents a novel and effective drying process for alum-adjuvanted vaccine formulations and is particularly valuable for dry powder applications such as EPI. © 2003 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 92:319,332, 2003 [source] Synthesis and properties of new dialkoxyphenylene quinoxaline-based donor-acceptor conjugated polymers and their applications on thin film transistors and solar cellsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 3 2009Mei-Hsiu Lai Abstract Synthesis, properties, and optoelectronic device applications of four new bis-[4-(2-ethyl-hexyloxy)-phenyl]quinoxaline(Qx(EHP))-based donor-acceptor conjugated copolymers are reported, in which the donors are thiophene(T), dithiophene(DT), dioctylfluorene(FO), and didecyloxyphenylene(OC10). The optical band gaps (Eg) of PThQx(EHP), PDTQ(EHP), POC10DTQ(EHP), and PFODTQ(EHP) estimated from the onset absorption are 1.57, 1.65, 1.77, and 1.92 eV, respectively. The smallest Eg of PThQx(EHP) among the four copolymers is attributed to the balanced donor/acceptor ratio and backbone coplanarity, leading to a strong intramolecular charge transfer. The hole mobilities obtained from the thin film transistor (TFT) devices of PThQx(EHP), PDTQ(EHP), POC10DTQ(EHP), and PFODTQ(EHP) are 2.52 × 10,4, 4.50 × 10,3, 4.72 × 10,5, and 9.31 × 10,4 cm2 V,1 s,1, respectively, with the on-off ratios of 2.00 × 104, 1.89 × 103, 4.07 × 103, and 2.30 × 104. Polymer solar cell based on the polymer blends of PFODTQ(EHP), PThQx(EHP), POC10DTQ(EHP), and PDTQ(EHP) with [6, 6]-phenyl C61-butyric acid methyl ester (PCBM) under illumination of AM1.5 (100 mW cm,2) solar simulator exhibit power conversion efficiencies of 1.75, 0.92, 0.79, and 0.43%, respectively. The donor/acceptor strength, molecular weight, miscibility, and energy level lead to the difference on the TFT or solar cell characteristics. The present study suggests that the prepared bis[4-(2-ethyl-hexyloxy)-phenyl]quinoxaline donor-acceptor conjugated copolymers would have promising applications on electronic device applications. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 973,985, 2009 [source] Genetic Polymorphisms Related to Delirium Tremens: A Systematic ReviewALCOHOLISM, Issue 2 2007Barbara C. Van Munster Background: Delirium tremens (DT) is one of the more severe complications of alcohol withdrawal (AW), with a 5 to 10% lifetime risk for alcohol-dependent patients. The 2 most important neurosystems involved in AW are , -aminobutyric acid and glutamate. It is unknown whether these neurosystems are involved in the pathophysiology of DT as well. The candidate gene approach in DT could contribute to this knowledge and demonstrate a possible genetic predisposition for DT. The purpose of this study is to give an overview of all studied genetic polymorphisms in the diverse candidate genes related to DT and to summarize what these studies contribute to insights into the pathophysiology of DT. Methods: The inclusion criteria for this literature study were articles in English analyzing the association between a genetic polymorphism and DT without other AW syndromes. Studies were identified until February 2006 in MEDLINE and EMBASE databases. Results: We found 25 studies dealing with 30 polymorphisms, located in 19 different genes. Positive associations were found in 3 different candidate genes involved in the dopamine transmission, 1 gene involved in the glutamate pathway, 1 neuropeptide gene, and 1 cannabinoid gene. Two candidate genes involved in the dopamine transmission, dopamine receptor D3, and solute carrier family 6, were each associated with DT in 2 different study populations. The other 4 positive associations were not replicated in other studies. Conclusions: A total of 8 positive associations out of 30 polymorphisms makes a genetic base for DT plausible. Understanding the pathophysiological process of the development of DT has, indeed, been augmented by the reviewed genetic association studies. These studies suggest that the regulation of dopaminergic neurotransmission may play an important role. [source] A randomized controlled trial of cognitive-behavior therapy for Cambodian refugees with treatment-resistant PTSD and panic attacks: A cross-over designJOURNAL OF TRAUMATIC STRESS, Issue 6 2005Devon E. Hinton We examined the therapeutic efficacy of a culturally adapted cognitive-behavior therapy for Cambodian refugees with treatment-resistant posttraumatic stress disorder (PTSD) and comordid panic attacks. We used a cross-over design, with 20 patients in the initial treatment (IT) condition and 20 in delayed treatment (DT). Repeated measures MANOVA, Group & times; Time ANOVAs, and planned contrasts indicated significantly greater improvement in the IT condition, with large effect sizes (Cohen's d) for all outcome measures: Anxiety Sensitivity Index (d = 3.78), Clinician-Administered PTSD Scale (d = 2.17), and Symptom Checklist 90-R subscales (d = 2.77). Likewise, the severity of (culturally related) neck-focused and orthostasis-cued panic attacks, including flashbacks associated with these subtypes, improved across treatment. [source] Additional Retardation in RAFT Polymerization: Detection of Terminated Intermediate RadicalsMACROMOLECULAR RAPID COMMUNICATIONS, Issue 7 2007Maël Bathfield Abstract The reversible addition-fragmentation chain transfer (RAFT) polymerization of N -acryloylmorpholine (NAM) is performed using three dithioesters (DT) as chain transfer agents (CTA) that incorporate a morpholine (morpholine-DT), a biotin (biotin-DT), or a sugar (sugar-DT) moiety in the R group. PolyNAM chains of controlled characteristics are synthesized. An unexpected behavior is observed with morpholine-DT, described as an ,additional retardation', which is especially visible when low molar masses are targeted (,<,5,000 g,·,mol,1). In that particular case, further investigations using MALDI-TOF mass spectrometry show the presence of terminated intermediate radicals (IRs), which corroborates the assumption based on a specific protection of IR according to the nature of the , -chain-end. [source] Evidence for enhanced functional activity of cervical cord in relapsing multiple sclerosisMAGNETIC RESONANCE IN MEDICINE, Issue 5 2008F. Agosta Abstract Functional MRI (fMRI) was used to assess proprioceptive-associated cervical cord activity in 24 relapsing multiple sclerosis (MS) patients and 10 controls. Cord and brain conventional and diffusion tensor (DT) MRI were also acquired. fMRI was performed using a block design during a proprioceptive stimulation consisting of a passive flexion-extension of the right upper limb. Cord lesion number, cross-sectional area, mean diffusivity (MD) and fractional anisotropy (FA), whole brain and left corticospinal tract lesion volume (LV), gray matter (GM) MD, and normal-appearing white matter (NAWM) MD and FA were calculated. MS patients had higher average cord fMRI signal changes than controls (3.4% vs. 2.7%, P = 0.03). Compared to controls, MS patients also had a higher average signal change in the anterior section of the right cord at C5 (P = 0.005) and left cord at C5,C6 (P = 0.03), whereas no difference was found in the other cord sections. Cord average signal change correlated significantly with cord FA and brain left corticospinal tract LV, GM-MD, and NAWM-FA. This study shows an abnormal pattern of activations in the cervical cord of MS patients following proprioceptive stimulation. Cord fMRI changes might have a role in limiting the clinical consequences of MS associated with irreversible tissue damage. Magn Reson Med 59:1035,1042, 2008. © 2008 Wiley-Liss, Inc. [source] In vivo diffusion tensor imaging of the human optic nerve: Pilot study in normal controlsMAGNETIC RESONANCE IN MEDICINE, Issue 2 2006C.A.M. Wheeler-Kingshott Abstract Diffusion tensor imaging (DTI) of the optic nerve (ON) was acquired in normal controls using zonally oblique multislice (ZOOM) DTI, which excites a small field of view (FOV) using a fast sequence with a shortened EPI echo train. This combines the benefit of low sensitivity to motion (due to the single-shot acquisition used), with the additional advantage of reduced sensitivity to magnetic field susceptibility artifacts. Reducing the bright signal from the fat and cerebrospinal fluid (CSF) surrounding the nerve are key requirements for the success of the presented method. Measurements of mean diffusivity (MD) and fractional anisotropy (FA) indices were made in a coronal section of the middle portion of the optic nerve (ON) in the right (rON) and left (lON) ONs. The average values across 10 healthy volunteers were FArON = 0.64 ± 0.09 and FAlON = 0.57 ± 0.10, and MDrON = (1173 ± 227) × 10,6 mm2 s,1 and MDlON = (1266 ± 170) × 10,6 mm2 s,1. Measurements of the principal eigenvalue of the DT and its orthogonal component were also in agreement with those expected from a highly directional structural organization. Magn Reson Med, 2006. © 2006 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||