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Various Degrees (various + degree)
Selected AbstractsPhotoreactivation in Paramecium tetraurelia under Conditions of Various Degrees of Ozone Layer Depletion,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2005Akihisa Takahashi ABSTRACT Photoreactivation (PR) is an efficient survival mechanism that helps protect cells against the harmful effects of solar-ultraviolet (UV) radiation. The PR mechanism involves photolyase, just one enzyme, and can repair DNA damage, such as cyclobutane-pyrimidine dimers (CPD) induced by near-UV/blue light, a component of sunlight. Although the balance of near-UV/blue light and far-UV light reaching the Earth's surface could be altered by the atmospheric ozone layer's depletion, experiments simulating this environmental change and its possible effects on life have not yet been performed. To quantify the strength of UVB in sunlight reaching the Earth's surface, we measured the number of CPD generated in plasmid DNA after UVB irradiation or exposure to sunlight. To simulate the increase of solar-UV radiation resulting from the ozone layer depletion, Paramecium tetraurelia was exposed to UVB and/or sunlight in clear summer weather. PR recovery after exposure to sunlight was complete at a low dose rate of 0.2 J/m2·s, but was less efficient when the dose rate was increased by a factor of 2.5 to 0.5 J/m2·s. It is suggested that solar-UV radiation would not influence the cell growth of P. tetraurelia for the reason of high PR activity even when the ozone concentration was decreased 30% from the present levels. [source] Facial and glossal distribution of anaesthesia after inferior alveolar nerve blockJOURNAL OF ORAL REHABILITATION, Issue 2 2003H.-K. Kim summary, The aim of this study was to subjectively determine the distribution of anaesthesia by mapping areas of sensory loss following inferior alveolar nerve block. Fifty healthy dental students were the subjects of this study (men 32, women 18). They were asked to draw the anaesthetized area on a diagram of the face and tongue 20 min after inferior alveolar nerve block. They evaluated the degree of anaesthesia by touching their faces and moving their tongues. All of the 50 subjects reported anaesthesia in the facial area. Of these, 21 (42%) reported the cutaneous distribution of anaesthesia on mental nerve territory only. Seventeen subjects (34%) reported anaesthesia on mental and buccal nerve territory. Nine subjects (18%) reported anaesthesia on mental, buccal, and auriculotemporal nerve territory. Two subjects (4%) reported anaesthesia on mental and auriculotemporal nerve territory and one subject (2%) on mental, buccal and infra-orbital nerve territory. Forty-seven of the 50 subjects (94%) reported anaesthesia of the tongue with the various degree of anaesthesia according to the area. Of these, 17 subjects (34%) reported strong anaesthesia on the anterior area and weak anaesthesia on the middle part of the tongue. Nineteen subjects (38%) reported strong anaesthesia of the lateral area and weak anaesthesia on the medial area, and 11 subjects (22%) reported anaesthesia on only the lateral side of the tongue. Three subjects (6%) reported no anaesthesia of the tongue. The distribution of anaesthesia of the facial and glossal regions determined subjectively after inferior alveolar nerve block, varies significantly between individuals. [source] Geochemical identification of projectiles in impact rocksMETEORITICS & PLANETARY SCIENCE, Issue 11 2006Roald Tagle The identification of a projectile component in impactites can be achieved by determining certain isotopic and elemental ratios in contaminated impactites. The isotopic methods are based on Os and Cr isotopic ratios. Osmium isotopes are highly sensitive for the detection of minute amounts of extraterrestrial components of even <<0.05 wt% in impactites. However, this only holds true for target lithologies with almost no chemical signature of mantle material or young mantle-derived mafic rocks. Furthermore, this method is not currently suitable for the precise identification of the projectile type. The Cr-isotopic method requires the relatively highest projectile contamination (several wt%) in order to detect an extraterrestrial component, but may allow the identification of three different groups of extraterrestrial materials, ordinary chondrites, an enstatite chondrites, and differentiated achondrites. A significant advantage of this method is its independence of the target lithology and post-impact alteration. The use of elemental ratios, including platinum group elements (PGE: Os, Ir, Ru, Pt, Rh, Pd), in combination with Ni and Cr represents a very powerful method for the detection and identification of projectiles in terrestrial and lunar impactites. For most projectile types, this method is almost independent of the target composition, especially if PGE ratios are considered. This holds true even in cases of terrestrial target lithologies with a high component of upper mantle material. The identification of the projectile is achieved by comparison of the "projectile elemental ratio" derived from the slope of the mixing line (target-projectile) with the elemental ratio in the different types of possible projectiles (e.g., chondrites). However, this requires a set of impactite samples of various degree of projectile contamination. [source] Scanning Electron Microscopic Study of the Lingual Papillae in the Arctic Fox (Alopex lagopus L., 1758)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2009H. Jackowiak Summary This study aims to show the distribution and the three-dimensional structure of the lingual papillae in the arctic fox. The macro- and microscopic structure of the tongue and its lingual papillae was studied in 11 adult arctic foxes. Two types of mechanical papillae were distinguished on the dorsal surface of the tongue , filiform papillae and conical papillae. The gustatory papillae in the arctic fox are represented by fungiform, vallate and foliate papillae. The keratinized filiform papillae on the anterior part of tongue are composed of one big posterior process accompanied by 10,12 secondary anterior processes. The number of anterior processes of filiform papillae undergo a complete reduction within the area between the posterior part of the body of the tongue and area of the vallate papillae. The conical papillae cover the whole dorsal surface of the root of the tongue, including the lateral parts surrounding the area of the vallate papillae and the posterior part of the root. The size of the conical papillae increases towards the root of the tongue but their density decreases. In the arctic fox, there are three pairs of vallate papillae distributed on the plan of a triangle. The diameter of vallate papillae in each successive pair is bigger. The wall surrounding the body of the vallate papilla and its gustatory trench is composed of six to eight conical papillae joined at various degree. The foliate papillae on both margins of the tongue consist of seven to nine laminae. [source] The crystalline lens higher fatty acids influence on the lens physical characteristicsACTA OPHTHALMOLOGICA, Issue 2009Y KUDRYAVTSEVA Purpose To study influence lipids of a crystalline lens on its physical characteristics. Methods 114 patients at the age from 55 till 78 years, with a cataract of various degree of a maturity are selected. Researches of a lens nucleus in vitro included: definition of mechanical hardness on the original device for research of mechanical hardness of a crystalline lens, research of composition of the higher fatty acids on the gas-liquid chromatograph. Results Influence of the higher fatty acids composition on mechanical hardness of a lens nucleus is revealed. Strong direct dependence between polyunsaturated fatty acids contents and hardness of a crystalline lens is found out. The correlation factor is equal 0.7 (? <0.05). Pentadecanic and stearic acids - the saturated fat acids have average correlation with hardness of lens - the correlation factor is accordingly equal -0.6 (? <0.05) and -0.6 (? <0.05), in spite of low contents in the lens. The palmitic acid contains in the cataract lens in concentration comparable to level polyunsaturated fatty acids, however, essential correlation with hardness has no - the correlation factor is equal 0.21 (p >0.05). The oleic, linolic and linolenic acids are contained in the cataract lens in low concentration and have average (v and linolic acids) - the correlation factor is accordingly equal -0.5 (? <0.05) and -0.57 (? <0.05) and weak correlation (linolenic acid) with hardness of a crystalline lens - the correlation factor is equal -0.22 (p> 0.05). Conclusion The polyunsaturated higher fatty acids which are a basis of membranes of a crystalline lens have the maximal influence on mechanical characteristics of the lens. [source] Taking the footing of a neutral mediatorCONFLICT RESOLUTION QUARTERLY, Issue 3 2006Brian L. Heisterkamp This study employs conversation analysis as a method for examining conversational footing in order to achieve mediator neutrality in a court-sanctioned mediation program. Data for the study are video recordings of actual mediation sessions. Participants include volunteer mediators and disputants who filed small claims cases at a county justice court. As first described by Goffman, conversational footing describes the various degrees of participation that interactants can have in relation to their own remarks. [source] Vascular endothelial growth factor in edematous mouse embryos induced by retinoic acid in uteroCONGENITAL ANOMALIES, Issue 2 2001Yoshiko Yasuda ABSTRACT, Vascular endothelial growth factor (VEGF) is induced by hypoxic environment and contributes to vascular formation in both developing embryos and adults. Exogenous retinoic acid (RA) induces avascular yolk sacs with anemic stunted embryos of day 9 and 10 of gestation when RA is given to pregnant mice on day 6, 6.5 or 7 of pregnancy (Yasuda et al., 1996). We undertook the present studies to find out whether VEGF is activated and plays any role in those RA-exposed embryos. Embryos were obtained from dams given 60 mg/kg of RA on day 6 or 7 of pregnancy and sacrificed three days later. Most RA-exposed embryos showed edematous swelling without prominent vascular nets, but had beating heart tubes on day 9 and day 10 of gestation. Microscopic examination of developing tissue components showed various degrees of degeneration, and distension of the dorsal aorta when the body cavity was dosed. Northern blot analysis revealed expression of VEGF mRNA in the RA-exposed and control embryos. The highest expression of VEGF mRNA was seen in the embryos of day 10 exposed to RA on day 7, and these embryos had a significantly lower ATP content than did the controls (p < 0.01). Immunoreactive VEGF was detectable in both experimental and control embryos; in the former it was especially visible in the distended neuroepithelium, endothelium and membranes. These VEGF-immunoreactive regions also expressed another permeability factor, bradykinin. These findings suggest that VEGF upregulated by hypoxic conditions in edematous embryos induced by RA exposure in utero acts as hyperpermeability. [source] Twilight Institutions: Public Authority and Local Politics in AfricaDEVELOPMENT AND CHANGE, Issue 4 2006Christian Lund ABSTRACT Public authority does not always fall within the exclusive realm of government institutions; in some contexts, institutional competition is intense and a range of ostensibly a-political situations become actively politicized. Africa has no shortage of institutions which attempt to exercise public authority: not only are multiple layers and branches of government institutions present and active to various degrees, but so-called traditional institutions bolstered by government recognition also vie for public authority, and new emerging institutions and organizations also enter the field. The practices of these institutions make concepts such as public authority, legitimacy, belonging, citizenship and territory highly relevant. This article proposes an analytical strategy for the understanding of public authority in such contexts. It draws on research from anthropologists, geographers, political scientists and social scientists working on Africa, in an attempt to explore a set of questions related to a variety of political practices and their institutional ramifications. [source] Histological alterations following thyroid fine needle biopsy: A systematic reviewDIAGNOSTIC CYTOPATHOLOGY, Issue 6 2009M.Sc., Stergios A. Polyzos M.D. Abstract Thyroid fine-needle biopsy (FNB) is a simple, reliable, inexpensive, and generally safe diagnostic procedure in the management of thyroid nodules. However, the trauma inflicted by the needle may lead to various degrees of histological alterations, observed in histological specimens, if thyroidectomy follows. Post-FNB histological alterations of the thyroid (PFHAT) can generally be divided into acute and chronic. Hemorrhage is the most common acute and fibrosis the most common chronic PFHAT. Some of the PFHAT causes problems in histological assessment, making diagnosis difficult, even leading to misdiagnosis. In this review, we tried to collect and summarize all reported PFHAT cases and studies, aiming to make involved physicians, cytologists, and pathologists aware of the spectrum of PFHAT and to provide information to help in differential diagnosis and to avoid misdiagnoses, which could lead to unnecessary radical surgery and/or adjuvant therapy. Diagn. Cytopathol. 2009. © 2009 Wiley-Liss, Inc. [source] ENDOSCOPIC MICROVASCULAR ARCHITECTURE OF THE PORTAL HYPERTENSIVE GASTRIC MUCOSA ON NARROW BAND IMAGINGDIGESTIVE ENDOSCOPY, Issue 3 2007Seishu Hayashi Background:, We evaluated the endoscopic microvascular architecture of the gastric mucosa in portal hypertension patients using the prototype of narrow band imaging (NBI). Material and Methods:, The study included 103 Helicobacter pylori -negative patients with chronic liver disease (22 without portal hypertension (group 1), 81 with portal hypertension (group 2)). Results:, (i) Abnormality of collecting venules, reddening mucosa, red spots, a mosaic-like pattern, and gastric antral vascular ectasia (GAVE) were observed on the gastric mucosa, and an obscure change in collecting venules (73% vs 14%; P < 0.001), reddening mucosa (49% vs 5%; P < 0.001), red spots (36% vs 5%; P < 0.01) and a mosaic-like pattern (40% vs 5%; P < 0.01) were more frequently observed in group 2 than in group 1. (ii) On magnifying endoscopy with NBI, the mucosa with an obscure change in collecting venules was demonstrated as dilation of the capillaries surrounding the gastric pits in various degrees, and reddening mucosa was observed as extended and swollen gastric pits and various degrees of dilated and convoluted capillaries surrounding the gastric pits. Red spots were demonstrated as extended and swollen gastric pits, dilated and convoluted capillaries surrounding the gastric pits, and intramucosal hemorrhage around these capillaries. GAVE was recognized as partial and marked dilatation of the capillaries surrounding the gastric pits. Conclusion:, Abnormality of collecting venules, swelling of gastric pits, dilatation of capillaries surrounding the gastric pits, intramucosal hemorrhage around capillaries, and partial and marked dilatation of the capillaries were observed on the gastric mucosa in portal hypertension patients. [source] Manometric study in Kearns,Sayre syndromeDISEASES OF THE ESOPHAGUS, Issue 1 2001K. H. Katsanos Although swallowing difficulties have been described in patients with Kearns,Sayre syndrome (KSS), the spectrum of manometric characteristics of dysphagia is not yet well known. Moreover, it is conceivable that a combination of various degrees of swallowing difficulties with different patterns in manometric studies exist, each playing a major role in the prognosis, natural history, and quality of life of KSS patients. An 18-year-old girl diagnosed at the age of 5 years with KSS (muscle biopsy) was admitted to our department with an upper respiratory tract infection and dysphagia. Clinical examination revealed growth retardation, external ophthalmoplegia, pigmentary retinopathy, impaired hearing, and ataxia. An electrocardiogram revealed cardiac conduction defects (long Q-T), and brain magnetic resonance imaging showed abnormalities in the cerebellar hemispheres. A manometric and motility study for dysphagia was conducted and the pharynx and upper esophageal sphincter (UES) resting pressures were similar to control group values, but the swallowing peak contraction pressure of the pharynx and the closing pressure of the UES were very low and could not promote effective peristaltic waves. Relaxation and coordination of the UES were not affected although pharyngeal and upper esophagus peristaltic waves proved to be very low and, consequently, were practically ineffective. The patient was started on treatment comprising a diet rich in potassium, magnesium, and calcium, and oral administration of vitamin D and co-enzyme Q10 100 mg daily; she was discharged 6 days later with apparent clinical improvement. [source] The earliest evidence of host,parasite interactions in vertebratesACTA ZOOLOGICA, Issue 2009evics, ns Luk Abstract Traces of parasite action have been discovered in the Middle,Upper Devonian fish from Estonia, Latvia and European Russia. Such traces are known in heterostracan Psammolepis venyukovi, antiarchs Asterolepis radiata and Bothriolepis ciecere, sarcopterygians Holoptychius sp., Ventalepis ketleriensis and Eusthenodon sp. nov. The traces include evidence of parasitic fixation and penetration as well as dwelling traces. Pathologies are developed as (1) round fossulae on the external surface of bones and scales; (2) oval fossulae with a slight elevation in the centre of the pit; (3) hollow swellings (possible galls); (4) openings (perforations) that have been repaired to various degrees; (5) variously shaped buttresses on the visceral surface of sarcopterygian scales; and (6) porous spongy formations on the non-overlapped surface of sarcopterygian scales. The round fossulae in sarcopterygian, placoderm and psammosteid skeletal elements could be produced by parasites that are similar to copepod crustaceans. Gall formation in Asterolepis is most likely to be caused by a larva, possibly of a trematode. The perforations of scales (and dermal bones) might arise from the attacks of ectoparasites (copepods?) or different worms. The spongy formations on the Holoptychius scales could be the result of invasion of a unicellular parasite. [source] Quantifying spatial classification uncertainties of the historical Wisconsin landscape (USA)ECOGRAPHY, Issue 2 2005Janine Bolliger Landscape feature can be classified by creating categories based on aggregation of spatially explicit information. However, many landscape features appear continuous rather than discrete. The aggregation process likely involves loss of information and introduces a variety of uncertainties whose degree and extent may differ spatially. Since landscape classifications have found wide application in e.g. natural resource policies or ecological research, assessments of spatial classification uncertainties are required. We present a quantitative framework to identify the degree of landscape continuity (fuzziness) and structure (categorization) based on fuzzy classification and offer measures to quantify uncertainties originating from aggregating features into categories. Fuzzy classification is a non-hierarchical, quantitative method of assessing class definitions using degrees of association between features and class. This results in classes which are well defined and compositionally distinct, as well as classes which are less clearly defined but which, to various degrees, share characteristics with some or all classes. The spatial variation in the degree of class definition on the landscape is used to assess classification uncertainties. The two aspects of uncertainty investigated are the degree of association of a feature with the overall class definitions (membership diffusion), and the class-specific degree of association of each pixel on the landscape with each class (membership saturation). Three classification scenarios, one fuzzy and one discrete, of the historical landscape of Wisconsin (USA) were compared for spatial classification uncertainties. Membership diffusion is highest in topographically heterogeneous environments, or areas characterized by many species occupying similar ecological niches. Classification uncertainties for individual classes show that differentiated species distributions can be identified, not only distribution centers. [source] Neuroradiologic Findings in Focal Cortical Dysplasia: Histologic Correlation with Surgically Resected SpecimensEPILEPSIA, Issue 2001Kazumi Matsuda Summary: ,Purpose: We investigated the neuroradiologic characteristics of focal findings of surgically resected specimens obtained from 47 patients with focal cortical dysplasia (FCD). Methods: Forty cases were detected by magnetic resonance imaging (MRI), and two cases were detected only by single-photon emission computed tomography (SPECT), but five cases could not be detected before operation. Results: MRI revealed abnormal gyri and sulci in 34 patients (pachygyric in 18, polymicrogyric in 10, both in six), and blurring of the gray matter,white matter junction in 29 (72%) patients. Signal abnormalities were found in 36 (90%) patients, in the gray matter in 32, with white matter in 30, and at the gray matter,white matter junction in 13. Moreover, peculiar patterns of abnormal signals in the white matter were recognized, including remarkably abnormal subcortical signals of T2 hyperintensity and T1 hypointensity adjacent to the dysplastic cortex in 15 cases, high radiated T2 signals extending from the ependymal surface of the lateral ventricle to the overlying cortex in 11 cases, and widespread abnormal signals in the white matter with gray matter involvement in four cases. Histologically, these abnormal signals corresponded to various degrees of dyslamination and morphologic abnormalities of neurons and glial cells in the gray matter, and to dysmyelination, ectopic clustering of dysplastic neurons, glial proliferation, and necrotic change in the white matter. Regional cerebral blood flow SPECT showed interictal hypoperfusion in 29 (62%) of the 47 patients, interictal hyperperfusion in two, and ictal hyperperfusion in 28 of the 34 patients associated with FCD. [123I]iomazenil SPECT demonstrating the distribution of central benzodiazepine receptors showed low accumulations localized spatially corresponding to the epileptogenic foci associated with FCD in seven of eight patients. Conclusions: These results demonstrate that neuroimaging reflects various structural and functional changes closely related to epileptogenesis in FCD. [source] Mitochondrial function and endocrine diseasesEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 4 2007R. Stark Abstract Mitochondria are fundamental for oxidative energy production and impairment of their functionality can lead to reduced ATP synthesis and contribute to initiation of apoptosis. Endocrine tissues critically rely on oxidative phosphorylation so that mitochondrial abnormalities may either be causes or consequences of diminished hormone production or action. Abnormalities typical for diseases caused by mitochondrial DNA mutations such as Kearns,Sayre syndrome or mitochondrial encephalomyopathy, lactic acidosis, and stroke,like episodes syndrome are also seen in certain endocrine diseases. Lack or excess of thyroid hormones, major ubiquitous regulators of mitochondrial content and activity, cause muscular abnormalities and multisystem disorders. Mitochondria are a further prerequisite for steroidogenesis as well as insulin secretion and action. Recent studies showed that reduced mitochondrial ATP synthesis in skeletal muscle is a feature of certain hereditary and acquired forms of insulin resistance and diabetes mellitus. Finally, ageing is not only accompanied by various degrees of hormonal deficiency and insulin resistance but is also associated with a progressive decline of mitochondrial number and function. Future research is needed to examine whether mitochondrial abnormalities are the cause or consequence of ageing and frequent metabolic diseases such as obesity and type 2 diabetes mellitus, and to address mitochondria as a target for novel therapeutic regimes. [source] The personality-identity interplay in emerging adult women: convergent findings from complementary analysesEUROPEAN JOURNAL OF PERSONALITY, Issue 3 2006Koen Luyckx Abstract The present study examined whether identity development occurs in tandem with personality development in emerging adulthood. Three-wave longitudinal data on a sample of 351 female college students were used to answer questions about stability and change, direction of effects, and interrelated developmental trajectories. Four identity dimensions (i.e. commitment making, exploration in breadth, identification with commitment, and exploration in depth) and the Big Five were assessed. Identity and personality were found to be meaningfully related at the level of both the time-specific adjacent measures and the underlying developmental trajectories with various degrees of convergence. Cross-lagged analyses substantiated reciprocal influences and Latent Growth Curve Modelling substantiated common developmental pathways that partially mirrored the concurrent relations. Implications and suggestions for future research are discussed. Copyright © 2006 John Wiley & Sons, Ltd. [source] Pemphigus mouse model as a tool to evaluate various immunosuppressive therapiesEXPERIMENTAL DERMATOLOGY, Issue 3 2009Yujiro Takae Abstract:, Pemphigus vulgaris (PV) is an autoimmune bullous disease caused by immunoglobulin G (IgG) autoantibodies against desmoglein 3 (Dsg3). We have generated an active disease mouse model for PV by adoptive transfer of Dsg3,/, lymphocytes. In this study, we investigated the benefits and limitations of this model as a tool to evaluate various immunosuppressive therapeutic strategies. We used the following three measurements to evaluate the effects of the drugs during the time course: Dsg3 enzyme-linked immunosorbent assay scores that represent the level of production of anti-Dsg3 IgG, body weight loss that reflects the severity of oral erosions and PV score that reflects the extent of skin lesions. We examined various immunosuppressive agents currently used to treat patients with PV model mice in preventive protocol. Cyclophosphamide almost completely suppressed the production of anti-Dsg3 IgG, development of body weight loss and the appearance of the PV phenotype in contrast with the control group without the drug. Azathioprine, cyclosporin A and tacrolimus hydrate also showed suppressive effects to various degrees. However, methylprednisolone and dexamethasone failed to show significant effects in contrast to the findings reported in humans. Knowing the advantages and limitations of this model will provide an important foundation for the future evaluation and development of novel therapeutic strategies. [source] Non-destructive evaluation of fatigue and creep-fatigue damage by means of the induced-current focused potential drop techniqueFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 12 2001Y. Sato Quantitative evaluation of damage accumulation including crack initiation and propagation is one of the major concerns of industrial plant management and plant licence renewal. In order to develop a novel non-destructive testing (NDT) and non-destructive evaluation (NDE) technique for damage evaluation, the induced-current focused potential drop (ICFPD), originally proposed for a defect inspection, was employed. In this study, ICFPD was successfully applied to a non-destructive damage evaluation based on crack measurements. The measurements were taken on fatigued specimens with various degrees of fatigue damage. The ICFPD can clearly detect and differentiate the damage accumulation processes including crack initiation, small crack growth and subsequent macroscopic crack growth. In order to demonstrate the applicability of damage evaluation assessments based on small crack measurements, ICFPD has also been applied to creep,fatigue loading where damage evaluation of a fusion reactor material is based on small crack measurements by the ICFPD technique and a novel methodology is proposed. [source] Priming the productivity pump: flood pulse driven trends in suspended algal biomass distribution across a restored floodplainFRESHWATER BIOLOGY, Issue 8 2006DYLAN S. AHEARN Summary 1. Chlorophyll a (Chl a) distribution across a 0.36 km2 restored floodplain (Cosumnes River, California) was analysed throughout the winter and spring flood season from January to June 2005. In addition, high temporal-resolution Chl a measurements were made in situ with field fluorometers in the floodplain and adjacent channel. 2. The primary objectives were to characterise suspended algal biomass distribution across the floodplain at various degrees of connection with the channel and to correlate Chl a concentration and distribution with physical and chemical gradients across the floodplain. 3. Our analysis indicates that periodic connection and disconnection of the floodplain with the channel is vital to the functioning of the floodplain as a source of concentrated suspended algal biomass for downstream aquatic ecosystems. 4. Peak Chl a levels on the floodplain occurred during disconnection, reaching levels as high as 25 ,g L,1. Chl a distribution across the floodplain was controlled by residence time and local physical/biological conditions, the latter of which were primarily a function of water depth. 5. During connection, the primary pond on the floodplain exhibited low Chl a (mean = 3.4 ,g L,1) and the shallow littoral zones had elevated concentrations (mean = 4.6 ,g L,1); during disconnection, shallow zone Chl a increased (mean = 12.4 ,g L,1), but the pond experienced the greatest algal growth (mean = 14.7 ,g L,1). 6. Storm-induced floodwaters entering the floodplain not only displaced antecedent floodplain waters, but also redistributed floodplain resources, creating complex mixing dynamics between parcels of water with distinct chemistries. Incomplete replacement of antecedent floodplain waters led to localised hypoxia in non-flushed areas. 7. The degree of complexity revealed in this analysis makes clear the need for high-resolution spatial and temporal studies such as this to begin to understand the functioning of dynamic and heterogeneous floodplain ecosystems. [source] Effects of ultraviolet radiation on the eggs of landlocked Galaxias maculatus (Galaxiidae, Pisces) in northwestern PatagoniaFRESHWATER BIOLOGY, Issue 3 2000M. Battini Summary 1Ultraviolet radiation (UVR) damages early life stages of several fish species. Galaxias maculatus is a small catadromous fish, with landlocked forms occurring in many lakes within the Nahuel Huapi National Park (Patagonia, Argentina). In this work, the vulnerability of G. maculatus eggs exposed to both natural and artificial UVR was investigated in relation to water transparency. 2Field experiments were performed in two lakes differing in UVR attenuation. Galaxias maculatus eggs were exposed to in situ levels of UVR in quartz tubes incubated at various depths. For laboratory experiments, the eggs were exposed to five levels of artificial UVB radiation. 3Exposure to natural UVR causes various degrees of egg mortality depending on water transparency and incubation depth. In the less transparent lake (Kd320 = 3.08 m -1), almost complete mortality was observed near the surface. At a depth of 43 cm the observed mortality was only 22%, but was still significantly different from the dark control. In the most transparent lake (Kd320 = 0.438 m -1), almost total mortality was observed in tubes incubated at 2.56 m or shallower. A gradual decline in mortality was recorded from that depth to 3.78 m where the values approached those in the dark control treatments. 4A monotonic relationship between mortality and UV exposure could be observed both in field and laboratory experiments. Using the results from field incubations, a LD50 of 2.5 J cm -2 nm -1 was estimated. In a few mountain lakes, this value would be exceeded even if the eggs were laid at the maximum depth of the lake. Thus UVR seems a sufficient cause to explain the absence of G. maculatus populations in some mountain lakes. For most lakes, however, UVR is probably one of several important environmental factors, which together determine the habitat suitability. [source] Projected changes in the organic carbon stocks of cropland mineral soils of European Russia and the Ukraine, 1990,2070GLOBAL CHANGE BIOLOGY, Issue 2 2007JO SMITH Abstract In this paper, we use the Rothamsted Carbon Model to estimate how cropland mineral soil carbon stocks are likely to change under future climate, and how agricultural management might influence these stocks in the future. The model was run for croplands occurring on mineral soils in European Russia and the Ukraine, representing 74 Mha of cropland in Russia and 31 Mha in the Ukraine. The model used climate data (1990,2070) from the HadCM3 climate model, forced by four Intergovernmental Panel on Climate Change (IPCC) emission scenarios representing various degrees of globalization and emphasis on economic vs. environmental considerations. Three land use scenarios were examined, business as usual (BAU) management, optimal management (OPT) to maximize profit, and soil sustainability (SUS) in which profit was maximized within the constraint that soil carbon must either remain stable or increase. Our findings suggest that soil organic carbon (SOC) will be lost under all climate scenarios, but less is lost under the climate scenarios where environmental considerations are placed higher than purely economic considerations (IPCC B1 and B2 scenarios) compared with the climate associated with emissions resulting from the global free market scenario (IPCC A1FI scenario). More SOC is lost towards the end of the study period. Optimal management is able to reduce this loss of SOC, by up to 44% compared with business as usual management. The soil sustainability scenario could be run only for a limited area, but in that area was shown to increase SOC stocks under three climate scenarios, compared with a loss of SOC under business as usual management in the same area. Improved agricultural soil management will have a significant role to play in the adaptation to, and mitigation of, climate change in this region. Further, our results suggest that this adaptation could be realized without damaging profitability for the farmers, a key criteria affecting whether optimal management can be achieved in reality. [source] Intraoperative radiation therapy as an "early boost" in locally advanced head and neck cancer: Preliminary results of a feasibility studyHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 6 2008Laura Marucci MD Abstract Background The acute toxicity of intraoperative radiation therapy (IORT) delivered as an "early boost" after tumor resection in patients with locally advanced head and neck cancer was evaluated. Methods Twenty-five patients were enrolled in the study. All patients underwent surgery with radical intent, and 17 had microvascular flap reconstruction. The IORT was delivered in the operating room. Twenty patients received adjuvant external beam radiation therapy (EBRT). Results Five patients experienced various degrees of complications in the postoperative period, all of which were treated conservatively. One patient had a partial flap necrosis after EBRT that was treated with flap removal. Six deaths were recorded during the mean follow-up period of 8 months; none of the deaths were related to radiation treatment. Conclusion This feasibility study shows that the use of IORT as an early boost is feasible with no increase in acute toxicity directly attributable to radiation. © 2008 Wiley Periodicals, Inc. Head Neck, 2008 [source] Empirical implications of response acquiescence in discrete-choice contingent valuationHEALTH ECONOMICS, Issue 10 2006Raymond Y. T. Yeung Abstract The use of discrete-choice contingent valuation (CV) to elicit individuals' preference, expressed as maximum willingness-to-pay (WTP), although primarily developed in environmental economics, has been popular in the economic evaluation of health and healthcare. However, a concern with this method is the potential for ,over-estimating' WTP values due to the presence of response acquiescence, or ,yea-saying' bias. Based on a CV survey conducted to estimate physicians' valuation of clinic computerization, the extent of such bias was estimated from a within-sample open-ended valuation question following the respondents' discrete choice response. Analysis of this data suggests that not only was response acquiescence an issue, but also that the parametric estimation of mean and median WTP, the most common approach to estimating WTP from discrete-choice data, would potentially magnify such bias (to various degrees depending on the distributional assumptions applied). The possible extent of CV design versus analysis in discrete-choice methods therefore warrants further exploration. Copyright © 2006 John Wiley & Sons, Ltd. [source] The relative sensitivity of willingness-to-pay and time-trade-off to changes in health status: an empirical investigationHEALTH ECONOMICS, Issue 6 2001Richard D. Smith Abstract This paper directly compares the relative sensitivity of time-trade-off (TTO) and willingness-to-pay (WTP) values obtained for various levels of change in health status. This was achieved by administering a TTO and WTP survey to a population of 50 subjects, assessing their valuation of various degrees of change in health status. It was found that, overall, WTP is more sensitive than TTO in distinguishing between different dimensions of health at the same nominal level of health status (only four WTP values not significantly different, compared with eight TTO values). In addition, WTP was also more sensitive to differences in quality of life between different levels of health within each dimension (all values significantly different from each other, with TTO yielding three insignificant relationships). These results tentatively suggest, therefore, that WTP seems to be a more sensitive measure of change in health status than TTO. Copyright © 2001 John Wiley & Sons, Ltd. [source] Activation of the complement system in human nonalcoholic fatty liver disease,HEPATOLOGY, Issue 6 2009Sander S. Rensen Activation of the innate immune system plays a major role in nonalcoholic fatty liver disease (NAFLD). The complement system is an important component of innate immunity that recognizes danger signals such as tissue injury. We aimed to determine whether activation of the complement system occurs in NAFLD, to identify initiating pathways, and to assess the relation between complement activation, NAFLD severity, apoptosis, and inflammatory parameters. Liver biopsies of 43 obese subjects with various degrees of NAFLD and of 10 healthy controls were analyzed for deposition of complement factors C1q, mannose-binding lectin (MBL), C4d, activated C3, and membrane attack complex (MAC)-associated C9. Furthermore, hepatic neutrophil infiltration, apoptosis, and pro-inflammatory cytokine expression were quantified. Whereas complement activation was undetectable in the liver of healthy subjects, 74% of the NAFLD patients showed hepatic deposition of activated C3 and C4d. C1q as well as MBL accumulation was found in most activated C3-positive patients. Strikingly, 50% of activated C3-positive patients also displayed MAC-associated C9 deposition. Deposition of complement factors was predominantly seen around hepatocytes with macrovesicular steatosis. Subjects showing accumulation of activated C3 displayed increased numbers of apoptotic cells. Importantly, hepatic neutrophil infiltration as well as interleukin (IL)-8 and IL-6 expression was significantly higher in patients showing activated C3 deposition, whereas patients with C9 deposition additionally had increased IL-1, expression. Moreover, nonalcoholic steatohepatitis (NASH) was more prevalent in patients showing hepatic C9 or activated C3 deposition. Conclusion: There is widespread activation of the complement system in NAFLD, which is associated with disease severity. This may have important implications for the pathogenesis and progression of NAFLD given the function of complement factors in clearance of apoptotic cells, hepatic fibrosis, and liver regeneration. (HEPATOLOGY 2009.) [source] Ionically Conducting Two-Dimensional HeterostructuresADVANCED MATERIALS, Issue 25-26 2009Xiangxin Guo Abstract In the context of revealing interfacial effects on ion conduction, thin films are extremely worthwhile due to defined geometry. Of particular interest are heterostructures as they offer symmetric boundary conditions and a high density of hetero-interfaces. The recent progress in this field is reviewed. Materials classes under concern include halides and oxides, and refer to various degrees of disorder and different mobilities. Even though in its infancy, the field of ionic heterostructures is already characterized by a variety of results of fundamental importance and of technological relevance. [source] The CAG repeat polymorphism within the androgen receptor gene and maleness,INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 2 2003Michael Zitzmann Summary The androgen testosterone and its metabolite dihydrotestosterone exert their effects on gene expression and thus effect maleness via the androgen receptor (AR). A diverse range of clinical conditions starting with complete androgen insensitivity has been correlated with mutations in the AR. Subtle modulations of the transcriptional activity induced by the AR have also been observed and frequently assigned to a polyglutamine stretch of variable length within the N-terminal domain of the receptor. This stretch is encoded by a variable number of CAG triplets in exon 1 of the AR gene located on the X chromosome. First observations of pathologically elongated AR CAG repeats in patients with X-linked spino-bulbar muscular atrophy showing marked hypoandrogenic traits were supplemented by partially conflicting findings of statistical significance also within the normal range of CAG repeat length: an involvement of prostate tissue, spermatogenesis, bone density, hair growth, cardiovascular risk factors and psychological factors has been demonstrated. The highly polymorphic nature of glutamine residues within the AR protein implies a subtle gradation of androgenicity among individuals within an environment of normal testosterone levels providing relevant ligand binding to ARs. This modulation of androgen effects may be small but continuously present during a man's lifetime and, hence, exerts effects that are measurable in many tissues as various degrees of androgenicity and represents a relevant effector of maleness. It remains to be elucidated whether these insights are important enough to become part of individually useful laboratory assessments. [source] The effect of nitric oxide on cyclooxygenase-2 (COX-2) overexpression in head and neck cancer cell linesINTERNATIONAL JOURNAL OF CANCER, Issue 5 2003Seok-Woo Park Abstract The overexpression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) has been previously reported in head and neck squamous cell carcinoma (HNSCC), as well as in many cancers. We hypothesized that endogenous nitric oxide (NO) might increase the expression of COX-2 in cancer cells. Therefore, we investigated the cross-talk between NO and the prostaglandin (PG) pathways in HNSCC cell lines. We found that COX-2 and iNOS expressions were elevated simultaneously. On adding the NO donor, SNAP, the PGE2 level was increased 2,20 times due to increased COX-2 expression. This increase of COX-2 expression by SNAP or PMA (potent inducer of both iNOS and COX-2) was blocked to various degrees by NO scavengers and NOS inhibitors (L-NAME and 1400W). Also, the expression of COX-2 in resting cells was inhibited by NOS inhibitors. Moreover, COX-2 expression, induced by SNAP, was inhibited by ODQ, a soluble guanylate cyclase (sGC) inhibitor. The effect of dibutyryl-cGMP on COX-2 expression was similar to that of SNAP. These results imply that endogenous or exogenous NO activates sGC and that the resulting increase of cGMP induces a signaling that upregulates the expression of COX-2 in HNSCC cell lines. We also observed that NO increased COX-2 expression in different cancer cell lines, including cervic and gastric cancer cell lines. These findings further support the notion that NO can be associated with carcinogenesis through the upregulation of COX-2, and that NOS inhibitor may be also useful for cancer prevention. © 2003 Wiley-Liss, Inc. [source] The prevalence of psychiatric symptoms and behavioural disturbances and the use of psychotropic drugs in Norwegian nursing homes,INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 9 2007Geir Selbęk Abstract Background Psychiatric and behavioural symptoms in dementia are associated with a range of negative outcomes, including institutional placement and the widespread use of psychotropic drugs in spite of limited evidence for their efficacy. Aims To determine the prevalence of psychiatric and behavioural symptoms and the pattern of psychotropic drug prescription in patients with various degrees of dementia. Methods A sample of 1,163 non-selected nursing home patients were assessed by means of the Neuropsychiatric Inventory, the Clinical Dementia Rating scale and Lawton's activities of daily living scale. In addition, information was collected from the patients' records. Results Dementia was found in 81% of the patients and 72% of them had clinically significant psychiatric and behavioural symptoms. The frequencies of symptoms increased with the severity of the dementia. Psychotropic medication was being prescribed to 75% of patients with dementia. There was a significant relationship between the type of drug and the symptom for which it had been dispensed. Conclusion Psychiatric and behavioural symptoms are frequent in nursing homes and the rate increases with the progression of the dementia. Systematic programmes are needed for disseminating skills and providing guidance regarding the evaluation and treatment of these symptoms in nursing homes. Copyright © 2006 John Wiley & Sons, Ltd. [source] The erythrocyte adhesiveness/aggregation test for the detection of an acute phase response and for the assessment of its intensityINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2002N. Maharshak Summary We have developed a simple slide test and image analysis to reveal the state of erythrocyte adhesiveness/aggregation in the peripheral blood of patients with various degrees of the humoral acute phase response. The significant correlation between the results of the erythrocyte adhesiveness/aggregation test (EAAT), the erythrocyte sedimentation rate and fibrinogen concentration support the notion that it is possible to use the EAAT as a marker for the intensity of the acute phase response. Within a group of 860 individuals, we were able to differentiate effectively between groups of patients with a different intensity of humoral acute phase response. The present study confirms previous observations that support the applicability of the EAAT to routine clinical practice. [source] | |||||||||||||||||||||||||||||||||||||||||||