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Linear Fashion (linear + fashion)
Selected AbstractsIsokinetic and isometric muscle strength in a healthy population with special reference to age and genderACTA PHYSIOLOGICA, Issue 2009B. Danneskiold-Samsøe Abstract Aim:, Muscle strength is an excellent indicator of general health when based on reliable measurements. Muscle strength data for a healthy population are rare or non-existent. The aim of the present study was to measure a set of normal values for isometric and isokinetic muscle strength for all the major joint movements of the body and, from these data, to create a basis for comparison of the muscle strength of an individual with the expected value in a normal population. Methods:, A randomly selected group, aged 20,80 years, from the Copenhagen City Heart Study were studied. The group was subgrouped according to age and gender. Isometric and isokinetic muscle strength was measured in each subject across the main joints in the body. A statistical model was developed that encompassed the three main muscle groups: upper limbs, trunk and lower limbs. Results:, Muscle strength in healthy men decreases in a linear fashion from the age of 25 years down to between 54% and 89% at the age of 75 years, and seems not highly dependent on any other parameter than age. For women, the muscle strength is dependent on weight and is only related to age from around 40 years of age. The decrease in muscle strength from the age around 40 to 75 years is 48,92%. For most muscle groups, men are 1.5,2 times stronger than women, with the oldest men having strength similar to that observed among the youngest women. Conclusion:, We developed a model to compare the isometric and isokinetic muscle strength of all the major joint movements of an individual with values for a healthy man or woman at any age in the range of 20,80 years. In all age groups, women have lower muscle strength than men. Men's muscle strength declines with age, while women's muscle strength declines from the age of 41 years. [source] Resilience thinking: Interview with Brian WalkerECOLOGICAL MANAGEMENT & RESTORATION, Issue 2 2007Tein McDonald Summary This interview with Brian Walker, chair of the research-based Resilience Alliance, outlines the main concepts and propositions behind ,resilience thinking' and touches on the importance of this paradigm for individuals and organizations involved in managing complex social-ecological systems. It refers to the origins, work and publications of the Resilience Alliance, listing and elaborating the key case studies used to illustrate the Alliance's main proposition that complex social-ecological systems do not behave in a predictable linear fashion. Rather, research indicates it is normal for complex systems to go through cycles of increasing and decreasing resilience and to have potential to shift, (in a self-organising way) to potentially undesirable states or entirely new systems if certain component variables are severely impacted by management. Such shifts can be novel and ,surprising', and are often not beneficial or desirable for societies. This is particularly the case where small-scale solutions push the problem upwards in a system, causing loss of resilience at a global scale. Predicting thresholds is therefore important to managers and is a key research focus for members of the Resilience Alliance who are currently building an accessible database to support decision-making in global natural resource management. [source] Highly diverse community structure in a remote central Tibetan geothermal spring does not display monotonic variation to thermal stressFEMS MICROBIOLOGY ECOLOGY, Issue 1 2006Lau Chui Yim Abstract We report an assessment of whole-community diversity for an extremely isolated geothermal location with considerable phylogenetic and phylogeographic novelty. We further demonstrate, using multiple statistical analyses of sequence data, that the response of community diversity is not monotonic to thermal stress along a gradient of 52,83°C. A combination of domain- and division-specific PCR was used to obtain a broad spectrum of community phylotypes, which were resolved by denaturing gradient gel electrophoresis. Among 58 sequences obtained from microbial mats and streamers, some 95% suggest novel archaeal and bacterial diversity at the species level or higher. Moreover, new phylogeographic and thermally defined lineages among the Cyanobacteria, Chloroflexi, Eubacterium and Thermus are identified. Shannon,Wiener diversity estimates suggest that mats at 63°C supported highest diversity, but when alternate models were applied [Average Taxonomic Distinctness (AvTD) and Variation in Taxonomic Distinctness (VarTD)] that also take into account the phylogenetic relationships between phylotypes, it is evident that greatest taxonomic diversity (AvTD) occurred in streamers at 65,70°C, whereas greatest phylogenetic distance between taxa (VarTD) occurred in streamers of 83°C. All models demonstrated that diversity is not related to thermal stress in a linear fashion. [source] The Substance of Sexual Difference: Change and Persistence in Representations of the Body in Eighteenth,Century EnglandGENDER & HISTORY, Issue 2 2002Karen HarveyArticle first published online: 16 DEC 200 The claims of Thomas Laqueur for a shift from a one,sex to a two,sex model of sexual difference are incorporated into many recent histories of gender in England between 1650 and 1850. Yet the Laqueurian narrative is not supported by discussions of the substance of sexual difference in eighteenth,century erotic books. This article argues that different models of sexual difference were not mutually exclusive and did not change in linear fashion, but that the themes of sameness and difference were strategically deployed in the same period. Thus, there was an enduring synchronic diversity which undermines claims for linear transformation. [source] Disruptive information system innovation: the case of internet computingINFORMATION SYSTEMS JOURNAL, Issue 4 2003Kalle Lyytinen Abstract., Information system (IS) innovation can be defined as a novel organizational application of digital computer and information communication technologies (ICT). This paper discusses how modalities of applying ICT technologies in their form and scope exhibit radical breaks, which are introduced herein as ,disruptive IS innovations'. This notion of disruptive IS innovation is developed by drawing upon and extending Swanson's (1994) theory of IS innovation as well as the concept of radical innovation. Disruptive innovations strongly influence the future trajectory of the adoption and use of ICT in organizational contexts and make the trajectory deviate from its expected course. In doing so, these disruptive innovations distinctly define what an IS is and how it is deployed in order to address current and future organizational and managerial prerogatives. Such changes are triggered breakthroughs in the capability of ICT that lead to the revision and expansion of associated cognitive models (frames) of computing. Disruptive IS innovations are those that lead to changes in the application of ICT that are both pervasive and radical. The pervasive nature implies that innovative activity spans all innovation subsets of the quad-core model of IS innovation introduced herein. Innovation types include: IS use and development processes; application architecture and capability; and base technologies. Radical in nature, disruptive is innovations depart in significant ways from existing alternatives and lead to deviation from expected use and diffusion trajectory. This paper demonstrates the importance of a concept of disruptive IS innovation by investigating how changes triggered by internet computing (Lyytinen et al., 1998) meet the conditions of a disruptive IS innovation defined herein. The analysis also affirms both the pervasive and radical nature of internet computing and explains how internet computing has fundamentally transformed the application portfolio, development practices and IS services over time. The analysis demonstrates that, with the concept of disruptive IS innovation, we can fruitfully analyse ,long' waves of ICT evolution , an issue that has largely been overlooked in the IS community. On a theoretical plane, the paper advocates the view that we need to look beyond linear, unidirectional, and atomistic concepts of the diffusion of IS innovations where innovative activity takes places in a linear fashion by oscillating between small technological innovations and small organizational innovations. In contrast, IS innovation can exhibit fundamental discontinuity; we need to theoretically grasp such disruptive moments. The recent influx of innovation, spurred by internet-based technology, offers one such moment. [source] Retrograde ureteroscopic endopyelotomy using the holmium:YAG laserINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2002Hatsuki Hibi Abstract Background: We report our experience of retrograde ureteroscopic endopyelotomy using the holmium laser for ureteropelvic junction (UPJ) obstruction not associated with upper tract stones. Methods: We carried out this procedure on five patients through an 8-Fr semirigid ureteroscope. The ureter was not stented before the procedure and balloon dilation was not necessary before retrograde insertion of the ureteroscope. The obstruction was incised with the holmium laser using a 200 µm fiber in a linear fashion. After completion of the incision, a 12-Fr double-J ureteral stent was left for 6 weeks. Thereafter, patients were monitored with renal scan and/or ultrasound and excretory urography at 3,6 month intervals. Results: Hydronephrosis was obviously improved in four cases (80%) at an average follow up of 12.8 months (4,23 months). Although the number of treated patients was small, retrograde ureteroscopic endopyelotomy for UPJ obstruction using the holmium laser achieved good results. Conclusions: We recommend that this procedure be used initially because it is less invasive and has a favorable outcome. [source] Voltage-dependent ebselen and diorganochalcogenides inhibition of 45Ca2+ influx into brain synaptosomesJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 3 2003M. B. Moretto Abstract By mediating the Ca2+ influx, Ca2+ channels play a central role in neurotransmission. Chemical agents that potentially interfere with Ca2+ homeostasis are potential toxic agents. In the present investigation, changes in Ca2+ influx into synaptosomes by organic forms of selenium and tellurium were examined under nondepolarizing and depolarizing conditions induced by high KCl concentration (135 mM) or by 4-aminopyridine (4-AP). Under nondepolarizing conditions, ebselen (400 ,M) increased Ca2+ influx; diphenyl ditelluride (40,400 ,M) decreased Ca2+ in all concentrations tested; and diphenyl diselenide decreased Ca2+ influx at 40 and 100 ,M, but had no effect at 400 ,M. In the presence of KCl as depolarizing agent, ebselen and diphenyl ditelluride decreased Ca2+ influx in a linear fashion. In contrast, diphenyl diselenide did not modify Ca2+ influx into isolated nerve terminals. In the presence of 4-AP (3 mM) as depolarizing agent, ebselen (400 ,M) caused a significant increase, whereas diphenyl diselenide and diphenyl ditelluride inhibited Ca2+ influx into synaptosomes. The results can be explained by the fact that the mechanism through which 4-AP and high K+ induced elevation of intracellular Ca2+ is not exactly coincident. The mechanism by which diphenyl ditelluride and ebselen interact with Ca2+ channel is unknown, but may be related to reactivity with critical sulfhydryl groups in the protein complex. The results of the present study indicate that the effects of organochalcogenides were rather complex depending on the condition and the depolarizing agent used. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:154,160, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10073 [source] Experimental Efficacy of Pericardial Instillation of Anti-inflammatory Agents during Percutaneous Epicardial Catheter Ablation to Prevent Postprocedure PericarditisJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2007ANDRE D'AVILA M.D. Introduction: Pericarditis is a potential complication of catheter-based percutaneous epicardial mapping and ablation. This study evaluates the efficacy and safety of intrapericardial instillation of anti-inflammatory agents after pericardial mapping and ablation in a porcine model of postprocedural pericarditis. Methods and Results: Twenty-five healthy swine underwent epicardial mapping and ablation after transthoracic subxyphoid puncture. After 60 minutes of continuous catheter manipulation in the pericardial space, radiofrequency energy was delivered in a linear fashion to the epicardial surfaces of both atria. The animals were randomly divided to receive the anti-inflammatory agents, Hyaluronic Acid and Triamcinolone, or control. Fourteen days after ablation, the hearts were excised and the degree of pericardial reaction/adhesions scored. The severity was uniformly graded 4 (intense) in all control animals and was characterized by intense adhesion between the parietal and the visceral pericardium obscuring tissue planes and epicardial anatomy. Hyaluronic Acid provided a mild benefit (score 3.0 ± 0.9), but 2 mg/kg of Triamcinolone significantly attenuated the inflammatory effect (all animals uniformly scored 1.0). Conclusion: In a porcine model of ablation-related pericarditis, intrapericardial instillation of 2 mg/kg of intermediate-acting corticosteroids effectively prevents post-procedure inflammatory adhesion formation. [source] Sonographic study of the development of fetal corpus callosum in a Chinese populationJOURNAL OF CLINICAL ULTRASOUND, Issue 2 2009Hai-chun Zhang MM Abstract Purpose The observation of fetal corpus callosum (CC) is important for the prenatal sonographic assessment of fetal central nervous system development. The aim of this study was to investigate the development of normal Chinese fetal CC. Method CC measurements were performed using high-resolution transabdominal sonography on 622 Chinese fetuses between 16 and 39 weeks' gestation. The correlation between CC size and gestational age was investigated. Results The fetal CC length increased in a linear fashion during pregnancy. The length of the CC as a function of gestational age was expressed by the following regression equation: length (mm) = ,9.567 + 1.495 × gestational age (weeks) (r = 0.932, p < 0.001). Conclusion Knowledge of normal CC appearance may help identify developmental anomalies and enable accurate prenatal counseling. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2009 [source] Attitudes toward Out-groups and the perception of consensus: All feet do not wear one shoeJOURNAL OF COMMUNITY & APPLIED SOCIAL PSYCHOLOGY, Issue 6 2008Anne Pedersen Abstract Although social perception research has been carried out across a number of diverse domains, to the best of our knowledge, studies have not directly assessed the relationship between attitudes toward the out-group and perceptions of community support for those attitudes. In the present research, we report the findings of a study conducted in Western Australia using data collected from 653 participants from three different locations. The main thrust of our study was the accuracy of beliefs about consensus as it related to attitudes toward two marginalized groups: Indigenous Australians and asylum seekers. With respect to their attitudes toward these two groups, our respondents were placed in seven categories corresponding to their responses to our seven point attitude scales. Three main findings emerged. First, respondents at all seven levels overestimated community support for their views with respect to both Indigenous Australians and asylum seekers. Second, as respondents in both groups became more rejecting, their estimates of community support progressively increased in a linear fashion. Third, respondents in the more negative categories were significantly less accurate in their estimates than those in the more positive categories. How these findings might contribute to programmes designed to reduce prejudice is discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source] Moving in social circles,social circle membership and performance implicationsJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 4 2007Willem Verbeke We investigate social circles in intra-firm settings. First, we argue that social circles are inhabited by individuals whose attitudes display fit with the objectives of the social circle rather than more self-centered instrumentalism or calculation. For a test of this hypothesis, we distinguish between friendship circles and strategy-influence circles. We find that friendship circle membership is positively associated with attitudes that display empathic concern but negatively with more instrumental attitudes, whereas strategy-influence circle membership is positively associated with attitudes that display long-term ambition but negatively with attitudes that display short-term calculation. Second, we argue and find that membership of social circles affects individual performance (social circles foster the exchange of information, for which we find clear evidence), albeit not necessarily in a linear fashion. Our new insights into social circle membership and performance implications can guide individuals in seeking access to such social circles and can aid management in understanding and perhaps influencing intra-firm knowledge flows. Copyright © 2006 John Wiley & Sons, Ltd. [source] Pharmacokinetics of fentanyl delivered transdermally in healthy adult horses , variability among horses and its clinical implicationsJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2006J. A. ORSINI The safety and pharmacokinetics of fentanyl, delivered transdermally at a dosage of 60,67 ,g/kg, were investigated in six healthy adult horses. Three transdermal fentanyl patches (Duragesic®), each containing 10 mg of fentanyl citrate, were applied to the mid-dorsal thorax of each horse and left in place for 72 h. Plasma fentanyl concentrations were periodically measured throughout this period and for 12 h after patch removal. After an initial delay of approximately 2 h, the plasma fentanyl concentration rose rapidly in a fairly linear fashion, reaching a peak at around 12 h; thereafter, it gradually declined in a roughly linear manner over the next 72 h. There was much individual variation, however. The initial delay ranged from 0 to 5.1 h (mean, 1.91 ± 2.0 h), Tcmax ranged from 8.5 to 14.5 h (mean, 11.4 ± 2.7 h) and Cmax ranged from 0.67 to 5.12 ng/mL (mean, 2.77 ± 1.92 ng/mL). In two horses, the plasma fentanyl concentration failed to reach even 1 ng/mL, whereas in the other four horses it was >1 ng/mL for at least 40 h and for at least 72 h in two of these horses. No adverse effects attributable to fentanyl were observed in any of the horses, indicating that this dosage is safe in systemically healthy adult horses. However, it failed to achieve plasma fentanyl concentrations generally considered to be analgesic (,1 ng/mL) in about one-third of horses. [source] Photocrosslinked DNA Nanospheres for Drug DeliveryMACROMOLECULAR RAPID COMMUNICATIONS, Issue 13 2010Young Hoon Roh Abstract DNA has been employed as both a genetic and a generic material. X-shaped DNA (X-DNA) in particular has four branched arms, providing multivalent functionalities that can allow for simultaneous multiple crosslinking. Here we report the synthesis of four acrylate-functionalized X-DNA monomers that can be further photocrosslinked to form monodisperse and tunable DNA nanospheres. In particular, the size and surface charge of these nanospheres were precisely controlled in a linear fashion, simply by tuning the monomer concentration in the reaction. The morphology and surface properties of the nanospheres were characterized using FT-IR, HPLC, TEM, AFM, zeta potential, and DLS analysis. In vitro studies in mammalian cells revealed that these DNA nanospheres demonstrated significant efficacy in the delivery of doxorubicin. These results highlight the potential of using DNA as material building blocks to design novel nanocarriers with properties tailored for the delivery of drugs in general and DNA/RNA in particular. [source] Modulation of the soleus H-reflex following galvanic vestibular stimulation and cutaneous stimulation in prone human subjectsMUSCLE AND NERVE, Issue 2 2009Catherine R. Lowrey MSc Abstract There is evidence to suggest that vestibular and somatosensory inputs may interact when they are processed by the central nervous system, although the nature of the individual sensory contributions to this interaction is unknown. We examined the effects of a combined vestibular and cutaneous conditioning stimulus on the motoneuron pool that supplies the soleus muscle via the Hoffman reflex (H-reflex). We applied galvanic vestibular stimulation (GVS; bipolar, binaural, 500 ms, 2.5-mA square-wave pulse) and cutaneous stimulation (medial plantar nerve; 11 ms, three-pulse train, 200 HZ) to prone human subjects and examined changes in the amplitude of the H-reflex. GVS alone caused facilitation (approximately 20%) of the H-reflex, whereas ipsilateral cutaneous stimulation alone caused a 26% inhibition. Paired GVS and cutaneous stimulation resulted in a linear summation of the individual conditioning effects. H-reflex amplitudes observed after paired conditioning with GVS and cutaneous stimulation could be predicted from the amplitudes observed with individual conditioning. These results suggest that in the prone position, when the muscles are not posturally engaged, vestibular and somatosensory information appear to sum in a linear fashion to influence the reflex response of lower limb motoneurons. Muscle Nerve 40: 213,220, 2009 [source] Addressing the epidemic of chronic kidney disease in AustraliaNEPHROLOGY, Issue 2004Timothy MATHEW SUMMARY: The Australia Diabetes, Obesity and Lifestyle Study (AUSDIAB) study provided, for the first time in Australia, a snapshot of the prevalence of kidney damage, reduced kidney function, hypertension and diabetes in the adult population. With this information, and the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) registry, that has recorded kidney failure statistics for many years, the extent of the chronic kidney disease burden in Australia is being better defined. This burden is even more pronounced in the Indigenous population where the incidence of kidney disease and kidney failure is increased several-fold. Diabetes is the second most common cause of kidney failure among Australians. The number of patients with diabetes accepted to dialysis has doubled in the last 7 years, the mean body weight of patients commencing dialysis has increased 7 kg in the past decade and the mean age at acceptance to dialysis is rising in a linear fashion (presently 60 years). These facts, together with a static transplant rate, all point to the prevalence of dialysis likely staying at or increasing beyond the present yearly growth rate of 6,7%. The evidence shows that a large proportion of chronic kidney disease patients are dying of cardiovascular risk factors before they reach dialysis or transplantation. There are many gaps in delivering appropriate preventative treatment to these patients. A relatively small reduction in the rise in dialysis numbers that might flow from an effective prevention of progression program, could make a significant impact on the spiralling numbers and associated cost of kidney failure treatment in Australia. We now need to develop and implement a national kidney disease strategy designed to address the whole continuum of chronic kidney disease from its earliest stage right through to dialysis and transplantation. [source] Apoptosis, anoikis and their relevance to the pathobiology of colon cancerPATHOLOGY INTERNATIONAL, Issue 4 2000Minalini Shanmugathasan The maintenance of a constant number of cells in an adult organism is a tightly regulated process. This is particularly important in organs where cells are in a constant rate of renewal during the entire lifespan. In these organs, cell number homeostasis is the direct consequence of a bal-ance between cell proliferation and apoptosis. The colonic epithelium is an example of such a site and the high prevalence of colon cancer makes the understanding of cell number homeostasis more important to define. Normal colonic epithelium is organized in crypts where cell proliferation, migration, differentiation and apoptosis are topographically organized in a linear fashion along the crypt axis. Normal colonic crypts are composed of stem cells at the base, a proliferation and a differentiation zone in the lower third of the crypt, a migration zone in the upper two-thirds, and the surface epithelium where senescent cells are eliminated by apoptosis. Globally, apoptosis can be defined as a normal process of cell suicide, critical for development and tissue homeostasis. Colonic epithelial cells migrate from the base of the crypt to the surface epithelium in 6,7 days. The normal architecture of the crypt is maintained by a balance between cell proliferation at the base and apoptosis at the top of the crypt and surface epithelium. [source] Essential work of fracture (EWF) analysis for compression molded alternating poly(propylene carbonate)POLYMER ENGINEERING & SCIENCE, Issue 3 2004K. L. Fung In this investigation, the main objective was to study the mechanical properties of alternating poly(propylene carbonate) copolymer (PPC). The PPC used in this study was derived from propylene oxide and carbon dioxide using zinc glutarate as catalyst. The molecular weight of the PPC copolymer used in this study has M,n,33,000. The synthesized PPC was compression molded into sheets of thickness ,1mm. The fracture toughness of the PPC films was determined using the essential work of fracture (EWF) technique, at a laboratory temperature of 20°C, and a loading rate of 1 mm/min. During the EWF measurement, a significant amount of plastic deformation has taken place around the initial ligament region. The measured specific total fracture work (wf) was observed to vary in a linear fashion with the specimen ligament (l), and hence satisfied the basic requirement for EWF analysis. The specific essential fracture work (we) for the PPC film was measured to be 11.0 kJ/m2. The PPC showed a prominent recovery behavior. The severely deformed region surrounding the fracture ligament was observed to recover completely 8 days after fracture testing. Polym. Eng. Sci. 44:580,587, 2004. © 2004 Society of Plastics Engineers. [source] Reference values of fetal orbital measurements by transvaginal scan in early pregnancyPRENATAL DIAGNOSIS, Issue 10 2002Paolo Rosati Abstract Objective To construct reference ranges of orbital diameters, measured in early pregnancy by transvaginal sonography. Methods The study group consisted of 2717 fetuses of pregnant women referred to our center and examined by transvaginal ultrasound between 11,16 week's gestation. Nomograms with confidence intervals (5th and 95th percentile) for each orbital measurement (orbital diameter, interocular and binocular distance) versus gestational age were produced. Results The orbital measurements increased in a linear fashion throughout early pregnancy with a good correlation with gestational age. Conclusion Transvaginal sonography is able to visualize and measure orbital diameters with accuracy in early pregnancy; reference ranges were developed that can be used to evaluate normal orbital development and can be helpful in the detection of syndromes with orbital growth defects and other associated fetal anomalies. Copyright © 2002 John Wiley & Sons, Ltd. [source] Comparison of Vaginal Cytokine Collection MethodsAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2006Constance J. Faro Objective The objective of our study was to correlate the interleukin-6 (IL-6) concentrations detected in patient-collected specimens with provider-collected specimens and compare the reproducibility of the methods. Study design All enrolled participants underwent pelvic examination with collection of cytokine samples by the provider and also collected samples themselves using vaginal swabs. The order of sample collection was randomly assigned. All samples were frozen at ,80°C for batch analysis. A commercial enzyme-linked immunosorbent assay was used to determine the concentrations of IL-6 in all samples. Results IL-6 concentrations from wicks and swabs were correlated in a linear fashion (r = 0.67, P < 0.001). IL-6 concentrations in the two swabs (r = 0.94, P < 0.001) and the two wicks (r = 0.71, P < 0.001) were correlated in a linear fashion, although there was more variability in wick specimens. Conclusion IL-6 concentrations can be reproducibly measured using either method. The ease of patient swab collection and the correlation with provider-collected specimens may make frequent assessment of the vaginal cytokine environment more acceptable to patients. [source] Two polymorphs of N -(2,6-difluorophenyl)formamideACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2009Bernard Omondi The structures of two distinct polymorphic forms of N -(2,6-difluorophenyl)formamide, C7H5F2NO, have been studied using single crystals obtained under different crystallizing conditions. The two forms crystallize in different space groups, viz. form (Ia) in the orthorhombic Pbca and form (Ib) in the monoclinic P21 space group. Each polymorph crystallizes with one complete molecule in the asymmetric unit and they have a similar molecular geometry, showing a trans conformation with the formamide group being out of the plane of the aromatic ring. The packing arrangements of the two polymorphs are quite different, with form (Ia) having molecules that are stacked in an alternating arrangement, linked into chains of N,H...O hydrogen bonds along the crystallographic a direction, while form (Ib) has its N,H...O hydrogen-bonded molecules stacked in a linear fashion. A theoretical study of the two structures allows information to be gained regarding other contributing interactions, such as ,,, and weak C,H...F, in their crystal structures. [source] Higher 25-hydroxyvitamin D is associated with lower relapse risk in multiple sclerosis,ANNALS OF NEUROLOGY, Issue 2 2010Steve Simpson Jr. MPH Objective A protective association between higher vitamin D levels and the onset of multiple sclerosis (MS) has been demonstrated; however, its role in modulating MS clinical course has been little studied. We investigated whether higher levels of serum 25-hydroxyvitamin D (25-OH-D) were associated with a lower risk of relapses in people with MS. Methods We conducted a prospective cohort study of 145 participants with relapsing-remitting MS from 2002 to 2005. Serum 25-OH-D levels were measured biannually, and the hazard of relapse was assessed using survival analysis. Results There was an inverse linear relationship between 25-OH-D levels and the hazard of relapse over the subsequent 6 months, with hazard ratio (HR) 0.91 (95% confidence interval [CI]: 0.85,0.97) per 10nmol/l increase in 25-OH-D level (p = 0.006). When variation due to timing of blood collection was removed by estimating 25-OH-D at the start of each season, this association persisted, with HR 0.90 (95% CI, 0.83,0.98) per 10nmol/l increase (p = 0.016). Taking into account the biological half-life of 25-OH-D, we estimated 25-OH-D at monthly intervals, resulting in a slightly enhanced association, with HR 0.88 (95% CI, 0.82,0.95) per 10nmol/l increase (p = 0.001). Adjusting for potential confounders did not alter these findings. Interpretation In this prospective population-based cohort study, in a cohort largely on immunomodulatory therapy, higher 25-OH-D levels were associated with a reduced hazard of relapse. This occurred in a dose-dependent linear fashion, with each 10nmol/l increase in 25-OH-D resulting in up to a 12% reduction in risk of relapse. Clinically, raising 25-OH-D levels by 50nmol/l could halve the hazard of a relapse. ANN NEUROL 2010;68:193,203 [source] Bis[2,4-diamino-5-(3,4,5-trimethoxybenzyl)pyrimidin-1-ium] dl -malateACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2009S. Franklin Racemic malic acid and trimethoprim [5-(3,4,5-trimethoxybenzyl)pyrimidine-2,4-diamine] form a 1:2 salt (monoclinic, P21/c), 2C14H19N4O3+·C4H4O52,, in which the malate component is disordered across a centre of inversion. The crystal structure of the salt consists of protonated trimethoprim residues and a malate dianion. The carboxylate group of the malate ion interacts with the trimethoprim cation in a linear fashion through pairs of N,H...O hydrogen bonds to form a cyclic hydrogen-bonded motif. This is similar to the carboxylate,trimethoprim cation interaction observed earlier in the complex of dihydrofolate reductase with trimethoprim. The structure of the salt of trimethoprim with racemic dl -malic acid reported here is the first of its kind. The present study investigates the conformations and the hydrogen-bonding interactions, which are very important for biological functions. The pyrimidine plane makes a dihedral angle of 78.08,(7)° with the benzene ring of the trimethoprim cation. The cyclic hydrogen-bonded motif observed in this structure is self-organized, leading to novel types of hydrogen-bonding motifs in supramolecular patterns. [source] Lichen striatus in a pregnant womanAUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 3 2005Sarah Brennand SUMMARY We report a case of lichen striatus in a 37-year-old woman in the third trimester of pregnancy. She presented at 35 weeks of pregnancy with a 6-week history of a pruritic rash on the left side of her abdomen. Examination revealed an erythematous papular eruption arranged in a linear fashion from the umbilicus to the left mid back. Histological examination demonstrated lichenoid perivascular and periadnexal inflammatory infiltrate and the presence of colloid bodies. The eruption resolved prior to delivery with the application of mometasone furoate 0.1% ointment. [source] How the CO in myoglobin acquired its bend: lessons in interpretation of crystallographic dataACTA CRYSTALLOGRAPHICA SECTION D, Issue 5 2001Boguslaw Stec Contrary to the expectation of chemists, the first X-ray structures of carbon monoxide bound to myoglobin (Mb) showed a highly distorted Fe,C,O bond system. These results appeared to support the idea of a largely steric mechanism for discrimination by the protein against CO binding, a lethal act for the protein in terms of its physiological function. The most recent independently determined high-resolution structures of Mb,CO have allowed the 25,year old controversy concerning the mode of CO binding to be resolved. The CO is now seen to bind in a roughly linear fashion without substantial bending, consistent with chemical expectations and spectroscopic measurements. Access to deposited diffraction data prompted a reevaluation of the sources of the original misinterpretation. A series of careful refinements of models against the data at high (1.1,Å) and modest resolutions (1.5,Å) have been performed in anisotropic versus isotropic modes. The results suggest that the original artifact was a result of lower quality crystals combined with anisotropic motion and limited resolution of the diffraction data sets. This retrospective analysis should serve as a caution for all researchers using structural tools to draw far-reaching biochemical conclusions. [source] On Estimation and Prediction for Spatial Generalized Linear Mixed ModelsBIOMETRICS, Issue 1 2002Hao Zhang Summary. We use spatial generalized linear mixed models (GLMM) to model non-Gaussian spatial variables that are observed at sampling locations in a continuous area. In many applications, prediction of random effects in a spatial GLMM is of great practical interest. We show that the minimum mean-squared error (MMSE) prediction can be done in a linear fashion in spatial GLMMs analogous to linear kriging. We develop a Monte Carlo version of the EM gradient algorithm for maximum likelihood estimation of model parameters. A by-product of this approach is that it also produces the MMSE estimates for the realized random effects at the sampled sites. This method is illustrated through a simulation study and is also applied to a real data set on plant root diseases to obtain a map of disease severity that can facilitate the practice of precision agriculture. [source] Keratosis lichenoides chronica in childhoodCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 4 2002P. Redondo Summary Keratosis lichenoides chronica (KLC) is a rare chronic disorder of keratinization characterized by lichenoid hyperkeratotic papules arranged in a linear pattern, erythematosquamous plaques and seborrhea-like dermatitis on the face. We report a 2-year-old girl diagnosed with KLC whose lesions, arranged in symmetrical linear fashion, improved after sunlight exposure during the summer. [source] | |||||||||||||||||||||||||||||||