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Common Phenomenon (common + phenomenon)
Selected AbstractsClustering of cardiovascular risk factors with diabetes in Chinese patients: the effects of sex and hyperinsulinaemiaDIABETES OBESITY & METABOLISM, Issue 3 2001Z. -R. SUMMARY Objective This study was designed to investigate factors which affect the clustering of cardiovascular risk factors with diabetes in Chinese patients. Research Design and Methods: Six hundred and fifty-four patients with diabetes were assessed comprehensively for diabetes complications and cardiovascular risk factors in a metropolitan hospital in Beijing, China. Insulin resistance and secretion were also evaluated by measurement of glucose and insulin levels before and after a meal tolerance test. Results were analysed according to patient groups stratified by the number of cardiovascular risk factors coexisting with diabetes. Results Cardiovascular risk factors were common in Chinese diabetic patients. The clustering of three or more of these factors with diabetes occurred more often than by chance alone and was associated with postprandial hyperinsulinaemia. Patients with a high number of risk factors were more prone to macrovascular events but did not have higher albuminuria. Using the commonly adopted lower threshold for diagnosing obesity and central obesity in women, there were more women with multiple risk factors. However, this disappeared if the same criteria were used for men and women. Even in the presence of diabetes, cardiovascular risk factors were inadequately controlled in most patients. Conclusions The concurrence of diabetes and other cardiovascular risk factors which constitute the metabolic syndrome is a common phenomenon in urban Chinese diabetic patients. It is associated with hyperinsulinaemia and possibly the female sex. This study emphasises the importance of public health measures to control cardiovascular risk factors in patients with diabetes. [source] Neuropathic pain and diabetesDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue S1 2003Dilip Kapur Abstract Neuropathic pain is a common phenomenon resulting from injury to the central or peripheral nervous system. The means by which diabetes results in nerve injury is unclear but the effect is to cause injury at all levels of the nervous system from the level of the peripheral nerves to the brain. Nerve injury causes pain through a cascade of mechanisms resulting in altered processing of sensory input into the nervous system. This alteration occurs through chemical and anatomical changes in the nervous system that are similar to some of the processes seen in central sensitisation following acute pain. Following nerve injury, neuropathic pain occurs not only when these mechanisms are activated but also when sensitisation is maintained. Other processes occurring in neuropathic pain appear to be a loss of normal inhibitory controls as seen by a reduction in local GABA-ergic and descending monoaminergic influences. There are also important changes mediated via glial cells that can maintain neuropathic pain. Diabetes affects all areas of the nervous system and the contribution of higher levels of the nervous system is often overlooked. Neurophysiological and MRI evidence strongly suggest that these may contribute to the pain of diabetic neuropathy. Psychological dysfunction in diabetic patients is an important factor in increasing the suffering associated with all aspects of the disease, but treatment and control of pain can greatly improve the quality of life. Copyright © 2003 John Wiley & Sons, Ltd. [source] Prediction of the behaviour of landslide dams using a geomorphological dimensionless indexEARTH SURFACE PROCESSES AND LANDFORMS, Issue 1 2003L. Ermini Abstract Landslide dams are a common phenomenon. They form when a landslide reaches the bottom of a river valley causing a blockage. The first effect of such a dam is the infilling of a lake that inundates the areas upstream, while the possibility of a sudden dam collapse, with a rapid release of the impounded waters, poses a higher flood risk to the downstream areas. The results of the main inventories carried out to date on landslide dams, have been examined to determine criteria for forecasting landslide dam evolution with particular emphasis on the assessment of dam stability. Not all landslides result in the blockage of a river channel. This only occurs with ones that can move a large amount of material with moderate or high-velocities. In most cases, these landslides are triggered by rainfall events or high magnitude earthquakes. A relationship also exists between the volume of the displaced material and the landslide dam stability. Several authors have proposed that landslide dam behaviour can be forecast by defining various geomorphological indexes, that result from the combination of variables identifying both the dam and the dammed river channel. Further developments of this geomorphological approach are presented in this paper by the definition of a dimensionless blockage index. Starting with an analysis of 84 episodes selected worldwide, it proved to be a useful tool for making accurate predictions concerning the fate of a landslide dam. Copyright © 2002 John Wiley & Sons, Ltd. [source] Isomer selectivity in aquatic toxicity and biodegradation of bifenthrin and permethrinENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2005Weiping Liu Abstract Synthetic pyrethroids are widely used insecticides, and contamination of surface aquatic ecosystems by pyrethroid residues from runoff is of particular concern because of potential aquatic toxicity. Pyrethroids also are chiral compounds consisting of multiple stereoisomers. In the present study, we evaluated the diastereomer and enantiomer selectivity of cis -bifenthrin (cis -BF) and permethrin (PM) in their aquatic toxicity and biodegradation. The 1R-cis enantiomer was the only enantiomer in cis -BF showing toxicity against Ceriodaphnia dubia. Incubation with pesticide-degrading bacteria showed that the trans diastereomer of PM was selectively degraded over the cis diastereomer, whereas the 1S-cis enantiomer in cis -BF or cis -PM was preferentially degraded over the corresponding 1R-cis enantiomer. The enantioselectivity was significantly greater for cis -PM than for cis -BF and also varied among different strains of bacteria. Isomer selectivity may be a common phenomenon in both aquatic toxicity and biodegradation of pyrethroids, and this should be considered when assessing ecotoxicological risks of these compounds in sensitive ecosystems. [source] Reannotation of hypothetical ORFs in plant pathogen Erwinia carotovora subsp. atroseptica SCRI1043FEBS JOURNAL, Issue 1 2008Ling-Ling Chen Over-annotation of hypothetical ORFs is a common phenomenon in bacterial genomes, which necessitates confirming the coding reliability of hypothetical ORFs and then predicting their functions. The important plant pathogen Erwinia carotovora subsp. atroseptica SCRI1043 (Eca1043) is a typical case because more than a quarter of its annotated ORFs are hypothetical. Our analysis focuses on annotation of Eca1043 hypothetical ORFs, and comprises two efforts: (a) based on the Z-curve method, 49 originally annotated hypothetical ORFs are recognized as noncoding, this is further supported by principal components analysis and other evidence; and (b) using sequence-alignment tools and some functional resources, more than a half of the hypothetical genes were assigned functions. The potential functions of 427 hypothetical genes are summarized according to the cluster of orthologous groups functional category. Moreover, 114 and 86 hypothetical genes are recognized as putative ,membrane proteins' and ,exported proteins', respectively. Reannotation of Eca1043 hypothetical ORFs will benefit research into the lifestyle, metabolism and pathogenicity of the important plant pathogen. Also, our study proffers a model for the reannotation of hypothetical ORFs in microbial genomes. [source] Larval lobster (Homarus americanus) distribution and drift in the vicinity of the Gulf of Maine offshore banks and their probable originsFISHERIES OCEANOGRAPHY, Issue 2 2005G. C. HARDING Abstract Surveys for lobster larvae in offshore waters of the north-eastern Gulf of Maine in 1983, 1987 and 1989 confirm that local hatching occurs mainly at depths <100 m over the banks, including Georges and Browns Banks. Detailed studies in the vicinity of Georges Bank in late July of both 1987 and 1989 indicate that the first and second moult stages were located primarily over the bank whereas stages III and IV lobster were collected both over and off the bank. At times stage IV lobster were more abundant off the bank than over it. The condition of stage III and IV lobster, as measured by a lipid index, was better off than over Georges Bank in 1988 and 1989 indicating a possible physiological advantage to being off the bank. In addition, the higher surface temperatures off Georges Bank would shorten larval development time to settlement. To determine the probable hatch sites of stage IV lobster collected off of Browns Bank in 1983 and off of Georges in 1987 and 1989, a 3-D circulation model of the Gulf of Maine was used to simulate larval lobster drift backwards in time. In all cases, areas off Cape Cod, MA, and off Penobscot Bay, ME were suggested as the source of the larvae, although most of the larval trajectories never reached these near-shore waters that are well-known, larval hatching areas. The model-projected larval release times match most closely the observed inshore hatch off Massachusetts but model uncertainties mean that coastal Maine cannot be ruled out as a source. Georges Bank is also a potential source because the present model does not take into account short-term wind events, off-bank eddy transport or the possibility of directed off-bank larval swimming. Examination of weather records prior to and during our 1988 and 1989 sampling periods indicates that winds were not of sufficient intensity and duration to induce larval transport off Georges Bank. The shedding of eddies from the northern flank of Georges Bank into the Gulf of Maine are a relatively common phenomenon during summer but not enough is known about them to evaluate their contribution to possible cross-bank transport of lobster larvae. Directed larval swimming is another possible source for the stage IV lobster found near Georges Bank. Plankton distributions across the northern frontal zone of Georges Bank in 1988 were used as proxies for the scarce larval lobsters. The more surface distribution of the microplankton, in particular, supports the possibility that wind and eddy events may be important in the transport of stage III and IV lobsters off of Georges Bank. Further studies are needed to evaluate these possible additional sources of advanced stage lobster larvae found off of the offshore banks. [source] Polyploidy-Associated Genomic Instability in Arabidopsis thalianaGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 4 2010Yixing Wang Formation of polyploid organisms by fertilization of unreduced gametes in meiotic mutants is believed to be a common phenomenon in species evolution. However, not well understood is how species in nature generally exist as haploid and diploid organisms in a long evolutionary time while polyploidization must have repeatedly occurred via meiotic mutations. Here, we show that the ploidy increased for two consecutive generations due to unreduced but viable gametes in the Arabidopsis cyclin a1;2-2 (also named tardy asynchronousmeiosis-2) mutant, but the resultant octaploid plants produced progeny of either the same or reduced ploidy via genomic reductions during meiosis and pollen mitosis. Ploidy reductions through sexual reproduction were also observed in independently generated artificial octaploid and hexaploid Arabidopsis plants. These results demonstrate that octaploid is likely the maximal ploidy produced through sexual reproduction in Arabidopsis. The polyploidy-associated genomic instability may be a general phenomenon that constrains ploidy levels in species evolution. [source] Wage policy in the health care sector: a panel data analysis of nurses' labour supplyHEALTH ECONOMICS, Issue 9 2003Jan Erik Askildsen Abstract Shortage of nurses is a problem in several countries. It is an unsettled question whether increasing wages constitute a viable policy for extracting more labour supply from nurses. In this paper we use a unique matched panel data set of Norwegian nurses covering the period 1993,1998 to estimate wage elasticities. The data set includes detailed information on 19 638 individuals over 6 years totalling 69 122 observations. The estimated wage elasticity after controlling for individual heterogeneity, sample selection and instrumenting for possible endogeneity is 0.21. Individual and institutional features are statistically significant and important for working hours. Contractual arrangements as represented by shift work are also important for hours of work, and omitting information about this common phenomenon will underestimate the wage effect. Copyright © 2003 John Wiley & Sons, Ltd. [source] Kings and sons: princely rebellions and the structures of revolt in western Europe, c.1170,c.1280*HISTORICAL RESEARCH, Issue 215 2009Björn Weiler Uprisings by royal sons against their fathers were a common phenomenon in the politics of medieval Europe, but one that, so far, has not been fully explored in the context of the thirteenth century. This was, however, a period during which numerous norms and mechanisms were developed that continued to define the Latin West well into the early modern period. This article uses three case studies (England 1173; Germany 1234; and Castile 1282) to outline both shared features of medieval European politics at large, and characteristic differences between central regions of the medieval West. [source] Spatial distribution of rare species in lotic habitatsINSECT CONSERVATION AND DIVERSITY, Issue 3 2008JOHN W. McCREADIE Abstract., 1Species rarity is a common phenomenon in the biological world. Although rare species have always interested biologists, the meaning of ,rare' has not always been clear with the definition of rarity often arbitrary. 2In the current study, we investigate rarity in stream ecosystems using black flies (Diptera: Simuliidae). We defined rare species a priori as those species found , 10% of stream sites examined (n = 111 streams for ,summer collections'; n = 88 collection for ,spring' collections). Hence, we are exploring only one axis of rarity, restricted range. 3We first consider the distribution of each rare species separately to determine if the mean (euclidian) distance among streams (habitats) for each rare species differs from a random model. We next took a collective approach by pooling all rare species to determine the influence of stream conditions, niche breadth, and distance among habitats on rarity. 4Even within this biologically uniform group of flies, dispersal, range limits, and stream conditions all might play a role in rarity, and the importance of each of these factors appear to vary among species. Rather than looking for broad causes of rarity, future studies might be more fruitful if they looked at species-specific causes. [source] Automated explanation of financial dataINTELLIGENT SYSTEMS IN ACCOUNTING, FINANCE & MANAGEMENT, Issue 1-2 2009H. A. M. Daniels We describe a methodology for explanation generation in financial knowledge-based systems. This offers the possibility to generate explanations and diagnostics automatically to support business decision tasks. The central goal is the identification of specific knowledge structures and reasoning methods required to construct computerized explanations from financial data and models. A multistep look-ahead algorithm is proposed that deals with so-called cancelling-out effects, which are a common phenomenon in financial data sets. Our method is an extension of the traditional variance decomposition in accounting. The method was tested on a case-study conducted for Statistics Netherlands involving the comparison of financial figures of firms in the Dutch retail branch. Copyright © 2009 John Wiley & Sons, Inc. [source] Tooth wear in two ancient populations of the Khazar Kaganat region in the UkraineINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 1 2007W. H. Arnold Abstract Tooth wear is a common phenomenon in archaeological material. It has been related to the abrasiveness of diet and to the tribological attrition of teeth of individuals. Numerous investigations have been carried out in north and middle American samples as well as African anthropological material. Not much is known about tooth wear in European cultures. Eleven skulls from Chervona Gusarovka, and 14 skulls from the Upper Saltov sites of the Khazar Kaganat region (8th,10th centuries AD) in eastern Ukraine, with different diets were examined. A total of 208 teeth were studied for tooth wear, caries prevalence and periodontal status. Abrasion grades were determined according to a standardised classification and statistically evaluated. Periodontal status was measured using the distance between the enamel-cementum junction and alveolar crest and the gingival attachment level respectively. Tooth wear was significantly different (P,<,0.01) between the two populations. A low caries prevalence of 4.2% in the Chervona Gusarovka population and 1.7% in the Upper Saltov population was found. Significantly more alveolar crest bone resorption on the lingual side was found in the premolars and anterior teeth of the Chervona Gusarovka population. No significant differences were found regarding gingival attachment levels and gingival recession. It is concluded that the content and mode of food preparation influenced tooth wear, as reflected by the prevalence of dental caries and periodontal diseases in these ancient populations. Copyright © 2006 John Wiley & Sons, Ltd. [source] Levels of comfort and ease among patients suffering from urinary incontinenceINTERNATIONAL JOURNAL OF UROLOGICAL NURSING, Issue 2 2007Michal Rassin Abstract Urinary incontinence is a common phenomenon among women, which harms social ties and is perceived as embarrassing and incurable. Despite its prevalence, there are few studies that have examined how those affected by this syndrome feel. The goal of this study was to examine the personal characteristics and levels of comfort among women suffering from urinary incontinence. The study included 50 women who had been diagnosed as suffering from urinary incontinence. The participants answered the Urinary Incontinence and Frequency Comfort Questionnaire, which examines levels of physical, mental, social and environmental comfort. , reliability has been found to be high in previous studies (,= 0·82). Our findings indicated that urinary incontinence occurred among the patients from several times a day to several times a week caused by sneezing, coughing and laughing. Most participants delayed treatment for up to 3 years. The general level of comfort was identified as medium low (SD = 0·04, M= 2·95) from a possible range of 1,6. Particularly low levels of comfort were recorded on items such as ,I feel clean and fresh,',finding a toilet in close proximity is a worrisome issue when I exit the house' and ,I fear having sex due to the urinary incontinence problem'. Identifying patients' needs and understanding their emotions are a useful basis for nursing intervention in promoting quality of life. [source] Persistence of Pulmonary Vein Isolation After Robotic Remote-Navigated Ablation for Atrial Fibrillation and its Relation to Clinical OutcomeJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2010STEPHAN WILLEMS M.D. Robotic Remote Ablation for AF. Aims: A robotic navigation system (RNS, HansenÔ) has been developed as an alternative method of performing ablation for atrial fibrillation (AF). Despite the growing application of RNS-guided pulmonary vein isolation (PVI), its consequences and mechanisms of subsequent AF recurrences are unknown. We investigated the acute procedural success and persistence of PVI over time after robotic PVI and its relation to clinical outcome. Methods and Results: Sixty-four patients (60.7 ± 9.8 years, 53 male) with paroxysmal AF underwent robotic circumferential PVI with 3-dimensional left atrial reconstruction (NavXÔ). A voluntary repeat invasive electrophysiological study was performed 3 months after ablation irrespective of clinical course. Robotic PVI was successful in all patients without complication (fluoroscopy time: 23.5 [12,34], procedure time: 180 [150,225] minutes). Fluoroscopy time demonstrated a gradual decline but was significantly reduced after the 30th patient following the introduction of additional navigation software (34 [29,45] vs 12 [9,17] minutes; P < 0.001). A repeat study at 3 months was performed in 63% of patients and revealed electrical conduction recovery in 43% of all PVs. Restudied patients without AF recurrence (n = 28) showed a significantly lower number of recovered PVs (1 (0,2) vs 2 (2,3); P = 0.006) and a longer LA-PV conduction delay than patients with AF recurrences (n = 12). Persistent block of all PVs was associated with freedom from AF in all patients. At 3 months, 67% of patients were free of AF, while reablation of recovered PVs led to an overall freedom from AF in 81% of patients after 1 year. Conclusion: Robotic PVI for PAF is safe, effective, and requires limited fluoroscopy while yielding comparable success rates to conventional ablation approaches with PV reconduction as a common phenomenon associated with AF recurrences. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1079-1084) [source] Atrial natriuretic factor inhibits mitogen-induced growth in aortic smooth muscle cellsJOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2002P.M. Baldini Atrial natriuretic factor (ANF) is a polypeptide able to affect cardiovascular homeostasis exhibiting diuretic, natriuretic, and vasorelaxant activities. ANF shows antimitogenic effects in different cell types acting through R2 receptor. Excessive proliferation of smooth muscle cells is a common phenomenon in diseases such as atherosclerosis, but the role of growth factors in the mechanism which modulate this process has yet to be clarified. The potential antimitogenic role of ANF on the cell growth induced by growth factors appears very intriguing. Aim of the present study was to investigate the possible involvement of ANF on rat aortic smooth muscle (RASM) cells proliferation induced by known mitogens and the mechanism involved. Our data show that ANF, at physiological concentration range, inhibits RASM cell proliferation induced by known mitogens such as PDGF and insulin, and the effect seems to be elicited through the modulation of phosphatidic acid (PA) production and MAP kinases involvement. J. Cell. Physiol. 193: 103,109, 2002. © 2002 Wiley-Liss, Inc. [source] Communication about consumption: a family process perspective on ,green' consumer practicesJOURNAL OF CONSUMER BEHAVIOUR, Issue 6 2006Alice Grønhøj Family decision-making still constitutes a niche of consumer research. The preference towards using individualist approaches is even more prevalent in research on environmentally oriented consumer behaviour. However, many green consumer practices involve several family members, who may be able to exert significant influences on household subscription to these practices. The present study used qualitative research methods to examine family member interaction in relation to four topics: organic food, water and energy, waste and transport. Results show that peaceful as well as more conflict-ridden, day-to-day influences between family members are a common phenomenon, even when it comes to inconspicuous, everyday consumer behaviour. Copyright © 2006 John Wiley & Sons, Ltd. [source] Burnout among nursing staff in two Finnish hospitalsJOURNAL OF NURSING MANAGEMENT, Issue 3 2000Koivula RN, MNSC Aim To describe burnout and factors affecting it in nursing staff. Background Burnout is a common phenomenon in nursing staff. We need knowledge of phenomena related to burnout in order to be able to properly direct measures decreasing burnout. Methods A questionnaire measuring burnout was answered by 723 nurses. The data were analysed by means of descriptive statistics and anova. Results Half of the staff had scores which indicated they were frustrated or burnt out. Personal resource variables having an influence on staff burnout were age, vocational education and years of practice. Burnout increases with age, and staff with short work experience in nursing practice experience lower levels of burnout. Staff with a secondary level education working on psychiatric wards experience especially high levels of burnout. Continuous professional education is related to lower levels of burnout if it lasts for more than 10 days over a period of 2 years. Conclusions The results of the study can be generalized only to these two Finnish hospitals. The results indicate that education, both vocational basic education and professional further education, are key factors in preventing burnout among nursing staff. [source] Immunological factors and their role in the genesis and development of endometriosis ARTICLE HAS BEEN RETRACTEDJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 2 2006Charalambos Siristatidis Abstract The article presents an overview of immunological factors and their role in the genesis and development of endometriosis, with emphasis on inflammatory cytokines and growth and adhesion factors. Although retrograde menstruation is a common phenomenon among women of reproductive age, not all women with retrograde menstruation suffer the disease. Development of endometriosis seems to be a complex process, facilitated by several factors, including quantity and quality of endometrial cells in peritoneal fluid (PF), increased inflammatory activity in PF, increased endometrial,peritoneal adhesion and angiogenesis, reduced immune surveillance and clearance of endometrial cells, and increased production of autoantibodies against endometrial cells. Potential biomarkers like cytokines and autoantibodies, upregulated during development of endometriosis, seem useful in the development of a non-surgical diagnostic tool. In this review work, the immune role in endometriosis is examined through the role of immunological factors in the genesis and development of the disease. Furthermore, it could be concluded that, although endometriosis can be treated using hormonal suppression, there is a need today for non-hormonal drugs, probably to modulate immune function, in order to confront the disease and alleviate pain or infertility without inhibition of ovulation. [source] Characterization of Phase Separation and Thermal History Effects in Magnesium Silicate Glass Fibers by Nuclear Magnetic Resonance SpectroscopyJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2009Jonathan F. Stebbins Liquid,liquid immiscibility, leading to the separation of silica-rich and silica-poor domains, is a common phenomenon in binary silicate glasses, but can be difficult to detect and characterize when rapid cooling results in nano-scale domain dimensions. 29Si nuclear magnetic resonance (NMR) spectroscopy can be very useful for detecting such phase separation, because the exclusion of paramagnetic impurity ions from the silica-rich regions can greatly slow their spin-lattice relaxation rates. Properly designed experiments can therefore largely isolate the NMR signals from high-silica and low-silica domains, and thus provide information about their proportions, compositions, and short- to intermediate-range structures. We demonstrate this approach here for fiber glasses that are predominantly magnesium, or calcium-magnesium silicates, with minor contents of alumina. For bulk compositions within the known region of stable liquid immiscibility, phase separation occurs even when extremely rapid cooling yields fibers less than 1 ,m in mean diameter. Slower cooling increases the extent of separation, while the addition of small amounts of alumina reduces it. [source] Evaluation of PCR primers from putative transcriptional regulator genes for identification of Staphylococcus aureusLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2005D. Liu Abstract Aims:, To examine if PCR primers derived from putative transcriptional regulator genes can be useful for Staphylococcus aureus identification. Methods and Results:,Staphylococcus aureus gene sequences that encode transcriptional regulators were retrieved from GenBank and compared with other DNA sequences via BLAST searches. Two uniquely present, putative transcriptional regulator genes (i.e. Sa0836 and Sa0856) were selected as a consequence and PCR primers (Sa0836F/R and Sa0856F/R) were then designed from these genes for evaluation. A total of 84 bacterial strains/isolates including 23 Staph. aureus, 18 nonaureus Staphylococcus and 43 other common bacterial isolates were examined. The results indicated that PCR primers from Sa0836 and Sa0856 recognized genomic DNA from Staph. aureus only, but not from other non-aureus Staphylococcus or common bacteria. Conclusions:, PCR detection of the putative transcriptional regulator genes Sa0836 and Sa0856 represents a useful means of identifying Staph. aureus from other bacteria. Significance and Impact of the Study:, The existence of species,species transcriptional regulator genes may be a common phenomenon in bacteria. Besides their value as novel diagnostic markers, further investigation on the putative transcriptional regulator genes Sa0836 and Sa0856 and their related products may shed light on the molecular mechanisms of Staph. aureus adaptation and virulence. [source] Single crystalline 2D porous arrays obtained by self organization in n-InPPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 1 2003S. Langa Abstract Self organization is a rather common phenomenon during pore formation in III,V semiconductors. The so called tetrahedron-like pores, the domains of crystallographically oriented pores in n-GaAs, or the macroscopic voltage oscillations in n-InP at high constant current densities are examples of a self organization process. In this paper we will discuss two-dimensional arrays of pores in n-InP with the unique property that they may form a single crystal as a result of a self organization process. The reasons for this long range order and its dependence on the etching conditions will be discussed. [source] Prefertilization barriers to interspecific hybridization involving Gossypium hirsutum and four diploid wild speciesPLANT BREEDING, Issue 3 2008S. Ganesh Ram Abstract Interspecific hybridization among species of cotton has lead to improvement in productivity, earliness, fibre quality and resistance to pests and diseases. However, wide crosses is often limited by the operation of either pre- or/and post-fertilization barriers. An investigation on pollen tube behaviour of four wild species in the pistils of Gossypium hirsutum was taken up. Pollen germination was normal in crosses involving Gossypium triphyllum and Gossypium armourianum and markedly inhibited in the crosses involving Gossypium davidsonii and Gossypium thurberi. Pollen tubes reached the pistils and fertilization was accomplished within 8 h after pollination (HAP) in control cross. Even though delay in pollen tube was a common phenomenon in all the four crosses successful fertilization was observed in crosses involving G. triphyllum and G. armourianum, as they reached the ovary at 24 HAP. In crosses with G. davidsonii and G. thurberi, pollen tubes failed to reach the ovary even at 24 HAP indicating the presence of strong stylar and ovarian incompatibility. Measures to overcome such barriers to interspecific hybridization in the incompatible crosses are discussed. [source] An engineered sorbitol cycle alters sugar composition, not growth, in transformed tobaccoPLANT CELL & ENVIRONMENT, Issue 10 2006MICHIHITO DEGUCHI ABSTRACT Many efforts have been made to engineer stress tolerance by accumulating polyols. Transformants that accumulate polyols often show growth inhibition, because polyols are synthesized as a dead-end product in plants that do not naturally accumulate polyols. Here, we show a novel strategy in which a sorbitol cycle was engineered by introducing apple cDNA encoding NAD-dependent sorbitol dehydrogenase (SDH) in addition to sorbitol-6-phosphate dehydrogenase (S6PDH). Tobacco plants transformed only with S6PDH showed growth inhibition, and very few transformants were obtained. In contrast, many transgenic plants with both S6PDH and SDH were easily obtained, and their growth was normal despite their accumulation of sorbitol. Interestingly, the engineered sorbitol cycle enhanced the accumulation of sucrose instead of fructose that was expected to be increased. Sucrose, rather than fructose, was also increased in the immature fruit of tomato plants transformed with an antisense fructokinase gene in which the phosphorylation of fructose was inhibited. A common phenomenon was observed in the metabolic engineering of two different pathways, showing the presence of homeostatic regulation of fructose levels. [source] Central anticholinergic syndrome secondary to atropine treatment of organophosphate poisoning,PSYCHOGERIATRICS, Issue 3 2006AN EROL, Demet DO Abstract Anticholinergic syndrome is a common phenomenon because of the frequent administration of atropine in organophosphate poisoning. This diagnosis should be considered in patients with altered mental state following therapy with atropine. We report a case of delirium 48 h after atropine treatment for organophosphate poisoning. [source] Gas-phase formation of protonated benzene during collision-induced dissociation of certain protonated mono-substituted aromatic molecules produced in electrospray ionizationRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2010Min Li Protonated benzene, C6H, has been studied extensively to understand the structure and energy of a protonated organic molecule in the gas phase. The formation of C6H is either through direct protonation of benzene, i.e., chemical ionization, or through fragmentation of certain radical cations produced from electron ionization or photon ionization. We report a novel observation of C6H as a product ion formed in the collision-induced dissociation (CID) of protonated benzamide and related molecules produced via electrospray ionization (ESI). The formation of C6H from these even-electron precursor ions during the CID process, which has not been previously reported, is proposed to occur from the protonated molecules via a proton migration in a five-membered ring intermediate followed by the cleavage of the mono-substituent CC bond and concurrent formation of an ion-molecule complex. This unique mechanism has been scrutinized by examining some deuterated molecules and a series of structurally related model compounds. This finding provides a convenient mean to generate C6H, a reactive intermediate of considerable interest, for further physical or chemical investigation. Further studies indicate that the occurrence of C6H in liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) appears to be a rather common phenomenon for many compounds that contain ,benzoyl-type' moieties. Hence, the observation of the C6H ion in LC/ESI-MS/MS can be used as an informative fragmentation pathway which should facilitate the identification of a great number of compounds containing the ,benzoyl-type' and similar structural features. These compounds are frequently present in food and pharmaceutical products as leachable impurities that require strict control and rapid elucidation of their identities. Copyright © 2010 John Wiley & Sons, Ltd. [source] Asymmetric allele-specific expression in relation to developmental variation and drought stress in barley hybridsTHE PLANT JOURNAL, Issue 1 2009Maria Von Korff Summary In the present study, we analysed allele-specific expression (ASE) in the selfing species barley to assess the frequency of cis -acting regulatory variation and the effects of genetic background, developmental differences and drought stress on allelic expression levels. We measured ASE ratios in 30 genes putatively involved in stress responses in five hybrids and their reciprocals, namely Hordeum spontaneum 41-1/Alexis (HAl), Hordeum spontaneum 41-1/Arta (HAr), Sloop/WI3408 (SW), Tadmor/Sloop (TS) and Tadmor/WI3408 (TW). In order to detect cis -acting variation related to drought and developmental changes, the barley hybrids were grown under control and water-limited conditions, and leaf tissue was harvested at two developmental stages. The analysis demonstrated that more than half of the genes measured (63%) showed allelic differences in expression of up to 19-fold due to cis -regulatory variation in at least one cross by treatment/stage combination. Drought stress induced changes in allelic expression ratios, indicating differences between drought responsive cis -elements. In addition, ASE differences between developmental stages suggested the presence of cis -acting elements interacting with developmental cues. We were also able to demonstrate that the levels and frequency of allelic imbalance and hence differences in cis -regulatory elements are correlated with the genetic divergence between the parental lines, but may also arise as an adaptation to diverse habitats. Our findings suggest that cis -regulatory variation is a common phenomenon in barley, and may provide a molecular basis of transgression. Differential expression of near-isogenic members of the same gene family could potentially result in hybrid lines out performing their parents in terms of expression level, timing and response to developmental and environmental cues. Identification and targeted manipulation of cis -regulatory elements will assist in breeding improved crops with a better adaptation to changing environments. [source] Detecting linkage disequilibrium in the presence of locus heterogeneityANNALS OF HUMAN GENETICS, Issue 3 2006D. Wang Summary Locus heterogeneity is a common phenomenon in complex diseases and is one of the most important factors that affect the power of either linkage or linkage disequilibrium (LD) analysis. In linkage analysis, the heterogeneity LOD score (HLOD) rather than LOD itself is often used. However, the existing methods for detecting linkage disequilibrium, such as the TDT and many of its variants, do not take into account locus heterogeneity. We propose two novel likelihood-based methods, an LD-Het likelihood and an LD-multinomial likelihood, to test linkage disequilibrium (LD) that explicitly incorporate locus heterogeneity in the analysis. The LD-Het is applicable to general nuclear family data but requires a working penetrance model. The LD-multinomial is only applicable to affected sib-pair data but does not require specification of a trait model. For affected sib-pair data, both methods have similar power to detect LD under the recessive model, but the LD-multinomial model has greater power when the underlying model is dominant or additive. [source] Conformational isomers of the [(5-methyl-2-pyridinio)aminomethylene]diphosphonate dianion and [(5-methyl-2-pyridyl)aminomethylene]diphosphonate trianion in salts with 4-aminopyridine and ammoniaACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2009Ewa Matczak-Jon The crystal structures of two salts, products of the reactions between [(5-methyl-2-pyridyl)aminomethylene]bis(phosphonic acid) and 4-aminopyridine or ammonia, namely bis(4-aminopyridinium) hydrogen [(5-methyl-2-pyridinio)aminomethylene]diphosphonate 2.4-hydrate, 2C5H7N2+·C7H10N2O6P22,·2.4H2O, (I), and triammonium hydrogen [(5-methyl-2-pyridyl)aminomethylene]diphosphonate monohydrate, 3NH4+·C7H9N2O6P23,·H2O, (II), have been determined. In (I), the Z configuration of the ring N,C and amino N,H bonds of the bisphosphonate dianion with respect to the Cring,Namino bond is consistent with that of the parent zwitterion. Removing the H atom from the pyridyl N atom results in the opposite E configuration of the bisphosphonate trianion in (II). Compound (I) exhibits a three-dimensional hydrogen-bonded network, in which 4-aminopyridinium cations and water molecules are joined to ribbons composed of anionic dimers linked by O,H...O and N,H...O hydrogen bonds. The supramolecular motif resulting from a combination of these three interactions is a common phenomenon in crystals of all of the Z -isomeric zwitterions of 4- and 5-substituted (2-pyridylaminomethylene)bis(phosphonic acid)s studied to date. In (II), ammonium cations and water molecules are linked to chains of trianions, resulting in the formation of double layers. [source] THE LOCAL EYE: FORMAL AND SOCIAL DISTINCTIONS IN LATE QUATTROCENTO NEAPOLITAN TOMBSART HISTORY, Issue 4 2008TANJA MICHALSKY The importation of foreign sculptors to Naples was a common phenomenon which both led to the amalgamation of divergent artistic forms of expression and also paved the way for innovative combinations which fulfilled the desire of the local nobility for hybrid, palimpsest-like tombs. This article examines the broader historical sensorium through which fifteenth- and sixteenth-century Neapolitans drew distinctions between local traditions and imported innovations when choosing artists, types and decorative styles for their funerary monuments. It demonstrates that the Neapolitan nobility was able to assimilate new and imported representational styles because it was accustomed to distinguishing between different styles and forms. A network of visually related monuments and surviving contracts testify to the typological rigour of the visual frameworks and to the recognized potentiality inherent in reinterpretations of earlier formulae. [source] Natural and Prosthetic Heart Valve Calcification: Morphology and Chemical Composition CharacterizationARTIFICIAL ORGANS, Issue 4 2010Raquel F. Weska Abstract Calcification is the most common cause of damage and subsequent failure of heart valves. Although it is a common phenomenon, little is known about it, and less about the inorganic phase obtained from this type of calcification. This article describes the scanning electron microscopy (SEM)/energy dispersive X-ray spectroscopy and Ca K -edge X-ray absorption near edge structure (XANES) characterization performed in natural and bioprosthetic heart valves calcified in vivo (in comparison to in vitro-calcified valves). SEM micrographs indicated the presence of deposits of similar morphology, and XANES results indicate, at a molecular level, that the calcification mechanism of both types of valves are probably similar, resulting in formation of poorly crystalline hydroxyapatite deposits, with Ca/P ratios that increase with time, depending on the maturation state. These findings may contribute to the search for long-term efficient anticalcification treatments. [source] | ||||||||||||||||||||||||||||||||||||||||