bluuebunny/crossref_metadata_2025 huggingface dataset:
Estudos de Comunidade e ciências sociais no Brasil
Authors: Oliveira Nemuel da Silva , Maio Marcos Chor
Published: March 2012

O objetivo deste artigo é fazer um balanço da literatura sobre os Estudos de Comunidade (EC) no Brasil, destacando o contexto intelectual em que foram produzidos e os debates que suscitaram, especialmente entre as décadas de 1940 e 1960. Método de pesquisa em comunidades, oriundo da Antropologia, em investigações sobre o processo de mudança social, os EC estiveram em voga nos Estados Unidos entre os anos 1920 e 1950, tendo papel fundamental na institucionalização das Ciências Sociais no Brasil. Destacamos três aspectos na produção desses estudos no país, iniciando com uma abordagem conceitual: definições, origem e sua relação com temáticas marcantes nos anos 1950. Em seguida, privilegiamos os aspectos relacionados ao papel dos EC na história das Ciências Sociais no Brasil, com destaque para o processo de institucionalização das Ciências Sociais. Por fim, revisitamos os debates que tais estudos geraram entre os cientistas sociais quanto ao padrão de trabalho sociológico a ser desenvolvido naquele momento.
Razões técnicas e efeitos simbólicos da incorporação do "progresso tecnocientífico": reprodução assistida e adoção de crianças
Authors: Ramírez-Gálvez Martha
Published: March 2012

As opções tecnológicas são também políticas, mas as implicações políticas das opções tecnológicas são obscurecidas por discursos, práticas e decisões que se apresentam como razões estritamente técnicas. Ao considerar o caso da reprodução assistida (RA), observamos que a busca pelo desenvolvimento técnico responderia, em principio, a razões meramente técnicas que buscariam a satisfação de um desejo "natural e atávico" de vivenciar a experiência corporal da gravidez, parto e amamentação, ancorado na naturalização do desejo de reprodução. No entanto, tais questões são reconsideradas neste artigo, em função da especificidade e singularidade do campo. Para a realização de tal análise, se coloca em perspectiva o campo da RA e de adoção de crianças. Resultados preliminares indicam que o uso de procedimentos de RA tiveram outros desdobramentos para além da consecução de um filho, ganhando um novo nicho de mercado: a função simbólica de elaboração de luto pelo filho biológico, considerada necessária para o amadurecimento do projeto de adoção de crianças.
Stonecutters Bridge, Hong Kong: the reference scheme
Authors: Withycombe Stuart , Firth Ian , Ove Jensen Poul
Published: March 2012

This paper describes the concept design for Stonecutters Bridge, Hong Kong – the winning scheme in the international design competition held by the Highways Department of the Hong Kong Special Administrative Region. The design was prepared by the competition winners, a team from Halcrow Group Ltd., Flint & Neill Partnership, the Shanghai Municipal Engineering Design Institute and Danish architects Dissing+Weitling. The concept design became the reference scheme for the development of the project.
Stonecutters Bridge, Hong Kong: ground investigations and seismic criteria
Authors: Thompson Peter A. , Pappin Jack
Published: March 2012

A preliminary ground investigation was undertaken in 1999 as part of the site investigation for Hong Kong's Route 8. Additional information was also available from other ground investigations undertaken for recent reclamation works. While this information provided an overview of the ground conditions for initial scheming it was inadequate for detailed design of Stonecutters Bridge. A detailed ground investigation was therefore procured in 2001, which was undertaken in three separate phases over a period of two years and described in this paper. Structures with long periods require design response spectra. For long period structures design response spectra are required. For Stonecutters Bridge, these were developed for various return periods using a probabilistic seismic hazard assessment (PSHA). The effects of the local soil profile were also explicitly considered. This paper summarises the PSHA and how the effects of the local soil profile were taken into account. The methods used to determine the dynamic response of the bridge and the effects of non-synchronous motion of the foundations are also explained.
Stonecutters Bridge, Hong Kong: stay cables and geometry control
Authors: Kite Steve , Yeung Ngai , Vejrum Tina
Published: March 2012

During the initial phase of the detailed design of Stonecutters Bridge, Hong Kong, site-assembled multi-strand stay cables were the preferred option owing to their ease of installation. However, when more detailed information on the wind climate at the bridge site became available during the detailed design, it became apparent that the wind effects were significantly higher than had been assumed during the review phase. As a result of this, the bridge could no longer be made to perform satisfactorily without extensive changes to the back-span superstructure unless more compact parallel wire system stays were used in the design. This paper describes the design of the stay cables, some of the tests carried out during fabrication and the geometry control of the bridge deck and towers during erection of the bridge.
Fatigue resistance of dynamically loaded self-compacting concrete
Authors: De Corte Wouter , Boel Veerle
Published: March 2012

The phenomenon of concrete fatigue is well documented in the literature for traditional concrete (TC), but this is not the case for self-compacting concrete (SCC). However, both concrete types differ substantially in composition and it remains to be seen whether all relevant mechanical properties including crack propagation and fatigue resistance are equal for SCC and TC mixtures of equal compressive strength. In this work, 32 reinforced concrete beams with varying reinforcement ratios and varying vertical stirrup quantities were subjected to static and dynamic loading until failure in a four-point bending rig. SCC and TC of equal compressive strength were delivered by a ready-mix concrete supplier. The imposed stress levels for dynamic loading were 0·10fcc–0·75fcc, 0·10fcc–0·80fccand 0·10fcc–0·85fcc. Structural behavioural properties such as deflections, strains and crack propagation corresponding to both static loads and fatigue loads were registered, and failure mechanisms during and after collapse were observed and analysed. The main conclusions are: different locations and types of failure were registered for ultimate load and fatigue load; the average crack width during static tests was smaller for SCC than for TC; for rebar fatigue failure, no difference was observed between SCC and TC; SCC appeared to have a higher direct compressive fatigue; crack width evolution during fatigue testing was substantially different for SCC and TC.
Use of recycled and secondary aggregates in foamed concretes
Authors: Jones Roderick , Zheng Li , Yerramala Amarnath , Rao Kharidu Srinivasa
Published: March 2012

This paper describes research into improved sustainable construction through the development of foamed concrete incorporating recycled and secondary aggregate fines (RSA). These were selected on the basis of being broadly available and/or significant local production but being otherwise difficult to utilise in structural fill or conventional normal weight concrete. The results indicate that the fine RSA can be successfully used to replace natural sand, either partially or fully. Data presented cover mix design, consistence and strength development. With respect to the results, significant advantage was obtained with the pozzolanic contribution of the conditioned fly ash. In addition, the performance of RSA foamed concretes in terms of drying shrinkage, water permeation, sulfate attack and thermal conductivity values are given. The data show that behaviour is mainly dependent on particle density and given RSA heterogeneity. It is necessary to trial mix unknown materials to enumerate foamed concrete performance.
Confined concrete model for columns under combined axial load and bending
Authors: Park Jong Yil , Lee Young Hak , Scanlon Andrew
Published: March 2012

A stress–strain curve model for confined concrete, which is essential for generating moment–curvature relationships for columns under constant axial loading, was developed by modifying Mander's confined concrete model. Two main assumptions adopted in Mander's model (45° arch action and yielding of tie bars) were tested and modified according to the theories of elasticity and strain compatibility, respectively. It was shown from the proposed confined concrete model that, although the 45° arch action assumption seems to be appropriate for confining effectiveness, tie bar stress may be far less than yield stress. A computer-based program was prepared to simulate moment–curvature relations of confined square concrete columns subjected to constant axial loading using the proposed concrete model. Numerical results from the proposed model were validated by comparing them with available laboratory test results; good agreement was found, especially in post-peak parts of moment–curvature relations.
Gauging climate change effects at local scales: weather‐based indices to monitor insect harassment in caribou
Authors: Witter Leslie A. , Johnson Chris J. , Croft Bruno , Gunn Anne , Poirier Lisa M.
Published: March 2012

Climate change is occurring at an accelerated rate in the Arctic. Insect harassment may be an important link between increased summer temperature and reduced body condition in caribou and reindeer (bothRangifer tarandus). To examine the effects of climate change at a scale relevant toRangiferherds, we developed monitoring indices using weather to predict activity of parasitic insects across the central Arctic. During 2007–2009, we recorded weather conditions and used carbon dioxide baited traps to monitor activity of mosquitoes (Culicidae), black flies (Simuliidae), and oestrid flies (Oestridae) on the post‐calving and summer range of the Bathurst barren‐ground caribou (Rangifer tarandusgroenlandicus) herd in Northwest Territories and Nunavut, Canada. We developed statistical models representing hypotheses about effects of weather, habitat, location, and temporal variables on insect activity. We used multinomial logistic regression to model mosquito and black fly activity, and logistic regression to model oestrid fly presence. We used information theory to select models to predict activity levels of insects. Using historical weather data, we used hindcasting to develop a chronology of insect activity on the Bathurst range from 1957 to 2008. Oestrid presence and mosquito and black fly activity levels were explained by temperature. Wind speed, light intensity, barometric pressure, relative humidity, vegetation, topography, location, time of day, and growing degree‐days also affected mosquito and black fly levels. High predictive ability of all models justified the use of weather to index insect activity. Retrospective analyses indicated conditions favoring mosquito activity declined since the late 1950s, while predicted black fly and oestrid activity increased. Our indices can be used as monitoring tools to gauge potential changes in insect harassment due to climate change at scales relevant to caribou herds.
Long‐term experimental loss of foundation species: consequences for dynamics at ecotones across heterogeneous landscapes
Authors: Peters Debra P. C. , Yao J
Published: March 2012

Biome transition zones where species co‐exist near their geographic limits are expected to be among the most responsive to changes in climate that result in mortality of foundation species. Long‐term (>13 years) patterns in dominance and cover of functional types were examined following the annual experimental removal of one of three foundation species at an arid‐semiarid biome transition zone. Objectives were to identify key processes influencing these patterns, and to predict future landscape‐scale dynamics following mortality of different foundation species. Aboveground biomass of dominant species was removed from 3 × 4 m plots. Cover by species on control and removal plots was estimated annually in communities with a single dominant species, and in ecotonal communities with two dominant species across two types of ecotones (semiarid grassland‐arid grassland, arid grassland‐arid shrubland).

For most species and functional types, trends in cover through time were related to the remaining species assemblages rather than to variable climatic conditions. In ecotonal communities, resident co‐dominant species increased to dominance following the loss of a foundation species with little change in community composition. In mono‐dominated communities, dominant species loss resulted in a shift to species that are currently sub‐dominants of the same functional type as the species that was removed. Subdominant perennial grass and shrub species increased rapidly following removals in most grassland locations. Annuals and perennial forbs had variable cover values through time that were not clearly related to pulses in precipitation and were not synchronized across locations. The most common response regardless of the identity of the foundation species removed or the community type was an increase in cover by sub‐dominant grasses and by the arid grass species (Bouteloua eriopoda). The rate of increase by B. eriopoda depended on initial cover, and resulted from both vegetative growth and seedling recruitment from other locations. Seed dispersal and seedling recruitment from other locations were not found for the semiarid grass, Bouteloua gracilis or the arid shrub, Larrea tridentata. Because B. eriopoda is more susceptible to shrub invasion, drought, and livestock grazing than the other two foundation species, widespread loss of either of the other species and subsequent increase in B. eriopoda is expected to result in an increase in landscape‐scale vulnerability to these environmental drivers. The extent and magnitude of this change in vulnerability will depend on the ability of B. eriopoda to respond based on the micro‐environmental conditions of the site regardless of which species (B. gracilis, L. tridentata) is lost.
Multiple Thoracic Hydatidosis: A Case Report
Authors: Mlika Mona , Ayadi-Kaddour Aida , El Mezni Faouzi
Published: March 2012

Background:

Multiple thoracic hydatidosis is uncommon even in endemic countries.
Case Presentation: A 37-year-old Caucasian man came to our observation with a 10-day history of basi-thoracic chest
pain and dyspnea. Chest X-ray showed a well limited cardiac opacity associated to an opacity of the upper lobe of the
right lung. Chest CT-scan showed a mediastinal cyst evoking a hydatid cyst in the left ventricle associated to a right
pleural effusion. The patient underwent surgery that consisted in the drainage of multiple pericardial cysts, cystectomy of
a left ventricle cyst and right pleural cystectomy. Microscopic examination showed a pleuro-pulmonary and cardiopericardial
hydatidosis. The patient was treated with albendazole and did not present complications or recurrences after
one year of follow up.

Conclusion:

Multiple thoracic hydatidosis is rare. Cardiac location is most challenging because it is difficult to manage
and life threatening. Treatment modalities continue to be based mainly on surgery. Preventive measures are necessary to
avoid disease recurrence.
Validation of Microcapillary Flow Cytometry for Community-Based CD4+ T Lymphocyte Enumeration in Remote Burkina Faso
Authors: Renault Cybèle A , Traore Arouna , Machekano Rhoderick N , Israelski Dennis M
Published: March 2012

Background

CD4+ T lymphocyte enumeration plays a critical role in the initiation and monitoring of HIV-infected patients on antiretroviral therapy. There is an urgent need for low-cost CD4+ enumeration technologies, particularly for use in dry, dusty climates characteristic of many small cities in Sub-Saharan Africa

Design

Cross-sectional study

Methods

Blood samples from 98 HIV-infected patients followed in a community HIV clinic in Ouahigouya, Burkina Faso were obtained for routine CD4+ T lymphocyte count monitoring. The blood samples were divided into two aliquots, on which parallel CD4+ measurements were performed using microcapillary (Guava EasyCD4) and dedicated (Becton Dickinson FACSCount) CD4+ enumeration systems. Spearman rank correlation coefficient was calculated, and the sensitivity, specificity and positive predictive value (PPV) for EasyCD4 <200 cells/µL were determined compared to the reference standard FACSCount CD4 <200 cells/µL

Results

Mean CD4 counts for the EasyCD4 and FACSCount were 313.75 cells/µL and 303.47 cells/µL, respectively. The Spearman rank correlation coefficient was 0.92 (p<0.001). Median values using EasyCD4 were higher than those with the FACSCount (p=0.004). For a CD4<350 cells/uL, sensitivity of the EasyCD4 was 93.9% (95%CI 85.2-98.3%), specificity was 90.6% (95% CI 75.0-98.0%), and PPV was 95.4% (95%CI 87.1-99.0%)

Conclusion

Use of the EasyCD4 system was feasible and highly accurate in the harsh conditions of this remote city in Sub-Saharan Africa, demonstrating acceptable sensitivity and specificity compared to a standard operating system. Microcapillary flow cytometry offers a cost-effective alternative for community-based, point-of-care CD4+ testing and could play a substantial role in scaling up HIV care in remote, resource-limited settings
Cholesterol Synthesis, Cholesterol Absorption, and Mortality in Hemodialysis Patients
Authors: Rogacev Kyrill S. , Pinsdorf Tobias , Weingärtner Oliver , Gerhart Markus K. , Welzel Elena , van Bentum Kai , Popp Julius , Menzner Andreas , Fliser Danilo , Lütjohann Dieter , Heine Gunnar H.
Published: March 2012

Background and objectives

Recent clinical trials on cholesterol-lowering in patients with CKD yielded conflicting results, which might have resulted from different treatment strategies. Serum cholesterol levels are determined by endogenous synthesis and intestinal absorption, which are differentially influenced by various classes of cholesterol-lowering agents. Assessing markers of cholesterol metabolism has thus been proposed for guidance of lipid-lowering therapy. This study analyzed surrogate markers of cholesterol absorption and synthesis in hemodialysis (HD) patients.

Design, setting, participants, & measurements

In 113 HD patients, lathosterol was measured as a marker of cholesterol synthesis and cholestanol was measured as a marker of cholesterol absorption via gas chromatography. Controls were 229 healthy persons. Overall survival in HD patients was recorded over 3.4-year follow-up.

Results

Compared with controls, HD patients had lower lathosterol and higher cholestanol levels (P<0.001 for both). During follow-up, 58 patients died; higher cholestanol (indicating higher cholesterol absorption) predicted poor outcome among HD patients in multivariate Cox regression analysis after adjustment for potential confounders (hazard ratio for cholestanol above median, 2.24 [95% confidence interval (CI), 1.29–3.89]; P=0.004), whereas lower lathosterol (indicating lower cholesterol synthesis) did not (hazard ratio for lathosterol below median, 1.43 [95% CI, 0.81–2.50]; P=0.22).

Conclusions

This analysis of markers of cholesterol metabolism characterizes HD patients as cholesterol absorbers. In longitudinal analysis, higher levels of cholestanol were associated with all-cause mortality.
Antibodies against Linear Epitopes on the Goodpasture Autoantigen and Kidney Injury
Authors: Jia Xiao-yu , Cui Zhao , Yang Rui , Hu Shui-yi , Zhao Ming-hui
Published: March 2012

Background and objectives

Linear epitopes on the Goodpasture autoantigen involved in human anti-glomerular basement membrane (GBM) disease are not fully defined. This study investigated the linear epitopes recognized by circulating antibodies in anti-GBM patients, aiming to identify the potential nephrogenic linear epitopes and their clinical significance.

Design, setting, participants, & measurements

Sixty-eight patients with anti-GBM disease were enrolled. Twenty-four overlapping linear peptides were synthesized across the whole sequence of the human Goodpasture autoantigen. ELISA detected circulating antibodies against linear epitopes. Their associations with clinical features were further analyzed.

Results

Antibodies against linear peptides were detected in sera from 55 patients (80.9%). Three major epitopes with high frequencies were identified: P14 (41%), P16 (36.8%), and P18 (57%). P14, a formerly defined T cell epitope, was a mutual B cell epitope. Antibodies against P14 were frequently detected in patients with positive antineutrophil cytoplasmic antibodies (39.3% versus 12.5%; P=0.01). Patients with anti-P16 antibodies presented with higher serum creatinine on diagnosis (665.5±227.2 versus 443.7±296.8 μmol/L; P=0.001) and worse renal outcome during follow-up (hazard ratio, 2.10; 95% confidence interval, 1.10–3.90; P=0.02). The level of anti-P18 antibodies positively correlated with the percentage of crescents in glomeruli (r=0.54; P=0.008). Recognition of P22 was an independent predictor for patient death (hazard ratio, 3.02; 95% confidence interval, 1.20–7.57; P=0.02).

Conclusions

Antibodies against linear epitopes on the Goodpasture autoantigen could be detected in human anti-GBM disease and were associated with kidney injury. P14 was a mutual T and B cell epitope, implying its nephrogenic role in disease initiation.
Collapsing Glomerulopathy in 19 Patients with Systemic Lupus Erythematosus or Lupus-Like Disease
Authors: Salvatore Steven P. , Barisoni Laura M. C. , Herzenberg Andrew M. , Chander Praveen N. , Nickeleit Volker , Seshan Surya V.
Published: March 2012

Background and objectives

Collapsing glomerulopathy is a podocytopathy with segmental or global wrinkling and collapse of capillary walls and overlying epithelial cell proliferation. Idiopathic collapsing glomerulopathy is a distinct clinicopathologic entity with significant proteinuria, poor response to immunosuppressive therapy, and rapid progression to renal failure. Collapsing glomerulopathy is associated with viral infections, autoimmune disease, and drugs. This work presents the largest group of collapsing glomerulopathy in patients with SLE.

Design, setting, participants, & measurements

Clinicopathological features were retrospectively studied in 19 patients with SLE (16 patients) or SLE-like (3 patients) disease with collapsing glomerulopathy.

Results

Initially, 95% of patients had nephrotic syndrome with proteinuria of 3–12 g per 24 hours, creatinine levels of 0.6–9.6 mg/dl, positive lupus serologies, and normal complement levels in 63%. Segmental and/or global collapsing glomerulopathy was seen in 11%–77% of glomeruli. Tubular atrophy with focal microcystic changes and interstitial fibrosis was seen in 35% of patients. Minimal glomerular mesangial deposits were noted in 63% of patients, and extensive foot process effacement was seen in 82% of patients. Initial treatment was with pulse/oral steroids. Follow-up from 13 patients revealed that 7 patients progressed to ESRD at the time of biopsy up to 21 months later, 1 patient returned to normal creatinine (1.1 mg/dl) without proteinuria, and 5 patients had creatinine of 1.2–3.6 mg/dl with proteinuria of 0.37–4 g per 24 hours.

Conclusions

Collapsing glomerulopathy may be seen in SLE patients presenting with massive proteinuria with or without lupus nephritis, which may have prognostic significance.
Effects of Sevelamer on HbA1c, Inflammation, and Advanced Glycation End Products in Diabetic Kidney Disease
Authors: Vlassara Helen , Uribarri Jaime , Cai Weijing , Goodman Susan , Pyzik Renata , Post James , Grosjean Fabrizio , Woodward Mark , Striker Gary E.
Published: March 2012

Background and objectives

Increased inflammation and oxidative stress may be caused by proteins and lipids modified by cytotoxic advanced glycation end products (AGEs) in food. Restricting food containing elevated AGEs improves these risk factors in diabetic CKD. Because diet adherence can be problematic, this study aimed to remove cytotoxic AGEs from food already ingested and to determine whether sevelamer carbonate sequesters cytotoxic AGEs in the gut, preventing their uptake and thereby reducing AGE-induced abnormalities.

Design, setting, participants, & measurements

This single-center, randomized, 2-month, open-label, intention-to-treat, crossover study compared sevelamer carbonate with calcium carbonate treatment in stage 2–4 diabetic CKD. Participants received 2 months of treatment with one drug, had a 1-week washout, and then received the opposite drug for 2 months.

Results

Sevelamer carbonate reduced HbA1c, serum methylglyoxal, serum εN-carboxymethyl-lysine, triglycerides, and 8-isoprostanes. Total cholesterol and fibroblast growth factor 23 were reduced by sevelamer carbonate, relative to calcium carbonate. AGE receptor 1 and sirtuin 1 mRNA were increased and PMNC TNFα levels were decreased by sevelamer carbonate, but not calcium carbonate. Medications and caloric and AGE intake remained unchanged. Sevelamer carbonate reversibly bound AGE-BSA at intestinal, but not stomach, pH.

Conclusions

Sevelamer carbonate significantly reduces HbA1c, fibroblast growth factor 23, lipids, and markers of inflammation and oxidative stress, and markedly increases antioxidant markers, independently of phosphorus in patients with diabetes and early kidney disease. These novel actions of sevelamer carbonate on metabolic and inflammatory abnormalities in type 2 diabetes mellitus may affect progression of early diabetic CKD.
Can cover crops reduce rabbit‐induced damages in vineyards in southern Spain?
Authors: Barrio Isabel C. , Villafuerte Rafael , Tortosa Francisco S.
Published: March 2012

Damage caused by wildlife foraging can lead to significant agricultural losses and the problem can be further complicated if the damage‐inducing animal is a valuable resource in its own right. Provision of alternative food sources such as cover crops might be a means of reducing the damage which appears to be linked to scarcity of alternative foods in intensively‐managed agroecosystems. Cover crops may provide other benefits to agroecosystems, i.e. preventing soil erosion but can potentially have some undesired consequences, i.e. water competition with the cash crop. In our study, we tested the effectiveness of cover crops in reducing the damage caused by foraging European rabbit Oryctolagus cuniculus to vineyards in a semi‐arid agroecosystem in southern Spain. Experimental treatments consisted of a combination of the presence/absence of sown cover crops (70% oat Avena sativa and 30% garden vetch Vicia sativa) with/without rabbit exclusion. In the 2009 growing season, we assessed rabbit‐induced damage using a browsing index on vine shoots, rabbit use of plots was estimated based on faecal pellet counts and grapevine yield was measured at harvest. Rabbits ate the cover crops, and rabbit use was highest in the plots sown with the oat and vetch cover crop. However, the effect of the presence of the cover crop on the amount of damage caused by rabbits was limited and, moreover, the presence of the cover crop had a negative effect on grapevine yield. Exclosure fences effectively reduced rabbit damage by keeping rabbit densities close to zero, but even a low rabbit number (∼ 1 rabbit/ha) can cause significant damage. Although cover crops provided rabbits with an alternative food source, they acted as attractants for rabbits and were not effective in reducing the damage caused to vineyards by higher rabbit numbers. Therefore, adding cover crops might not be an effective measure in controlling rabbit‐induced damage in semi‐arid wine‐growing regions.
Monitoring and population estimation of the European badger Meles meles in Northern Ireland
Authors: Reid Neil , Etherington Thomas R. , Wilson Gavin J. , Montgomery W. Ian , McDonald Robbie A.
Published: March 2012

The estimation of animal abundance has a central role in wildlife management and research, including the role of badgers Meles meles in bovine tuberculosis transmission to cattle. This is the first study to examine temporal change in the badger population of Northern Ireland over a medium‐ to long‐term time frame of 14‐18 years by repeating a national survey first conducted during 1990‐1993. A total of 212 1‐km2 squares were surveyed during 2007‐2008 and the number, type and activity of setts therein recorded. Badgers were widespread with 75% of squares containing at least one sett. The mean density of active main setts, which was equivalent to badger social group density, was 0.56 (95% CI: 0.46‐0.67) active main setts per km2 during 2007‐2008. Social group density varied significantly among landclass groups and counties. The total number of social groups was estimated at 7,600 (95% CI: 6,200‐9,000) and, not withstanding probable sources of error in estimating social group size, the total abundance of badgers was estimated to be 34,100 (95% CI: 26,200‐42,000). There was no significant change in the badger population from that recorded during 1990‐1993. A resource selection model provided a relative probability of sett construction at a spatial scale of 25 m. Sett locations were negatively associated with elevation and positively associated with slope, aspect, soil sand content, the presence of cover, and the area of improved grassland and arable agriculture within 300 m.
Modelling of microstructural evolution on complex paths of large plastic deformation
Authors: Petryk Henryk , Stupkiewicz Stanisław
Published: March 2012

A procedure for the modelling of microstructural changes induced by non-uniform large plastic deformation of metals is developed. For a given plastic working process, a set of deformation paths for different initial locations of a material element is generated first for a non-hardening material by using the finite element method. Next, changes of a cellular microstructure and related hardening effects along each path are calculated by using a recently proposed model. The procedure is applied to a non-conventional process of cold extrusion assisted by cyclic rotation of the die. The evolution of microstructural parameters, their effect on strain hardening and a distribution map over the specimen cross-section are calculated.
Metal-oxide-modified nanostructured carbon application as novel adsorbents for chromate ion removal from water
Authors: Moradi Seyyed Ershad , Baniamerian Mohammad Javad
Published: March 2012

In the present work, nickel oxide and iron oxide nanoparticles were synthesized inside the pore system of nanoporous carbon and were used as adsorbents to remove hexavalent chromium. The structural order and textural properties of the new carbonaceous adsorbents were studied by X-ray diffraction analysis and nitrogen adsorption. Experiments were conducted in batch mode with the variables such as contact time and solution pH. Adsorption equilibrium was achieved within 3–4 h for initial Cr(VI) of 10–100 mg.L−1. Maximum sorption capacity of Ni–NC and Fe–NC was observed as 0.86 mmol.g−1 and 1.17 mmol.g−1 respectively.
Mechanical properties and biodegradable behavior of Mg–6%Zn–Ca3(PO4)2 metal matrix composites in Ringer's solution
Authors: Zhao Jun , Yu Kun , Chen Liangjian , Li Shaojun , Hu Yanan , Lei Lu
Published: March 2012

The purpose of this study is to investigate the mechanical properties of Mg–6%Zn–Ca3(PO4)2 composite and evaluate its biodegradable behavior in Ringer's solution. The Mg–6%Zn alloy with 5%, 10% and 15% addition of Ca3(PO4)2 as reinforcements are produced through a powder-metallurgy sinter method and their corrosion properties are tested. The results show that the mechanical properties of the Mg–6%Zn–Ca3(PO4)2 composites are adjustable by the addition and particle distributions of Ca3(PO4)2. The Mg–6%Zn–5%, 10%Ca3(PO4)2 composites obtain properties including density, Young's modulus, and strength similar to natural bone. The Mg matrix, Mg7Zn3 phase, and Ca3(PO4)2 are identified in the experimental composite. Immersion and electrochemical corrosion tests reveal that 5% and 10% addition of Ca3(PO4)2 particles in the Mg–6%Zn alloy exhibit acceptable corrosion resistance in Ringer's solution.
Numerical simulation of the evolution of primary and secondary Nb(CN), Ti(CN) and AlN in Nb-microalloyed steel during continuous casting
Authors: Zamberger Sabine , Pudar Milan , Spiradek-Hahn Krystina , Reischl Michael , Kozeschnik Ernst
Published: March 2012

The precipitation of carbides and nitrides in Nb-microalloyed steel is investigated experimentally and theoretically using light optical, scanning and transmission electron microscopy, and the thermokinetic software MatCalc. The simulations are based on a recently developed two-step methodology for precipitation simulation in primary solidification microstructures, where the compositional inhomogeneities from microsegregation are taken into account. The computed segregation is clearly evidenced in electron probe microanalyses of the as-cast microstructure. Based on the results of a Scheil–Gulliver simulation, precipitation kinetics simulations are performed with the chemical compositions corresponding either to the solute-rich interdendritic zone or the solute-depleted dendrite core zone. The predicted phase fractions, mean radii, number densities, and compositions of the precipitates are in good agreement with the experimental investigations.
Hydrogen permeability with dislocation in low carbon, aluminium-killed, enamel-grade steels
Authors: Csiszár Gábor , Fábián Enikoő Réka , Ungár Tamás , Dévényi László
Published: March 2012

The role of dislocations on hydrogen permeation time of Al-killed, unalloyed low-carbon steels was investigated using a special high-resolution double crystal diffractometer operated at a rotating copper anode with fine focus. Information about dislocation character and Burgers vector populations are given by strain anisotropy. Generally, the hydrogen permeability increases or decreases with dislocation densities but hydrogen accumulation proved to be less favourable near a screw dislocation than an edge dislocation.
CNT-based displacement sensor
Authors: Karimov Khasan S. , Saleem Muhammad , Karieva Zioda M. , Khan Adam , Mateen Abdul
Published: March 2012

In this study, carbon-nanotubes-based Al/CNT/Al displacement sensors were designed, fabricated by deposition of the carbon nanotubes on an adhesive elastic polymer tape, and placed in the elastic casing, and investigated. The diameter of multiwalled nanotubes varied between 10–30 nm. The thickness of the carbon nanotube layers in the samples was 300–430 μm. The interelectrode distance (length) and width of the surface-type samples were in the range of 4–6 mm and 3–4 mm, respectively. The DC resistance of the sensors from different batches was decreased on average by 3 times as the displacement was increased up to 900 μm. The resistance–displacement relationships were supported by simulation.
Calorimetric investigations of liquid gold–antimony–tin alloys
Authors: Hindler Michael , Mikula Adolf
Published: March 2012

Calorimetric investigations have been done on the Au–Sb–Sn system with a Calvet-type micro-calorimeter. The partial and integral enthalpies of mixing in the ternary system were determined at six cross-sections at 873 K. Three additional cross-sections were measured at 1073 K to check if there are any temperature dependencies. No temperature dependence could be found. The substitutional solution model of Redlich–Kister–Muggianu was used for a least-square fit of the experimental data in order to get an analytical expression for the integral enthalpy of mixing. The isoenthalpy curves for the Au–Sb–Sn system were constructed at 873 K. The Chou model was used to calculate the enthalpies of mixing for the ternary system. The calculated values were then compared with the experimental data. The calculated data are in very good agreement with the experimentally determined values.
Design of damage tolerance in high-strength steels
Authors: Münstermann Sebastian , Lian Junhe , Bleck Wolfgang
Published: March 2012

With the extensive application of advanced high-strength steels in various fields due to their excellent mechanical properties, industrial interest in the damage of advanced high-strength steels has increased in recent years. For these modern steels, due to their multiphase microstructure and different deformation mechanisms, the concept of damage must be re-examined. In this paper, the definition, length scale and different mechanisms of damage are introduced. Both the experimental evaluation of damage and the numerical damage models are briefly reviewed and compared. The approaches to improving damage tolerance are given in the framework of the damage tolerance design principle.
Effect of strain rate and dynamic strain ageing on work-hardening for aluminium alloy AA5182-O
Authors: Lademo Odd-Geir , Engler Olaf , Benallal Ahmed , Sture Hopperstad Odd
Published: March 2012

The work-hardening of the solution-strengthened aluminium alloy AA5182-O is studied as a function of strain rate at room temperature. The main aim is to characterize the influence of strain rate and dynamic strain ageing on the work-hardening of the material. Tensile tests with constant nominal strain rates in the range from 10−6 to 1 s−1 were carried out; additionally, strain-rate jump tests were performed. The material exhibits a sharp yield point, a Lüders plateau, and serrated yielding within the actual range of strain rates. This indicates that the steady-state strain rate sensitivity is negative as a result of dynamic strain ageing. The serrations in the stress–strain curves and the work-hardening are markedly reduced with increasing strain rates. In most cases, the jump tests exhibit the standard behaviour, i.e., after a transient period following the jump in strain rate, the stress–strain curve converges to the steady-state stress–strain curve at the new strain rate.
Direct preparation of ferrite magnetic material from Jinchuan nickel sulfide concentrate by acid leaching
Authors: Zhu Huihui , Yu Ranbo , Deng Jinxia , Chen Jun , Xing Xianran
Published: March 2012

A preparation route of ferrite magnetic material by leaching of Jinchuan nickel sulfide concentrates in hydrochloric acid was developed. Pre-roasting of the concentrates could significantly improve the leaching efficiency of nickel. X-ray diffraction measurements, thermogravimetric, and differential thermal analyses were used to determine the phase transition after pre-roasting. The leaching could extract almost 100% nickel and 89% iron. The present process involved pre-roast of nickel sulfide concentrate, hydrochloric acid leaching at ambient pressure, solid–liquid separation, co-precipitation, and calcination. The nickel ferrite doped with Cu2+ and Mg2+ could be obtained by co-precipitation and calcination. Further study confirmed that ferrite products were of spinel structure and exhibit good ferromagnetism.
Investigation of the surface of a laser-treated cast iron cylinder bore
Authors: Májlinger Kornél , Szabó Péter J.
Published: March 2012

The pollution materials emission standards in Europe are going to be more strict. In order to meet the environmental standards, a European automotive manufacturer performs a finishing laser treatment on the honed cylinder bores of their V-engine blocks. Samples of laser treated cast iron cylinder bores with lamellar graphite were investigated. In order to evaluate the microstructure and grain size of the laser-treated layer, scanning electron micrographs were taken on cross-sectioned samples with a scanning electron microscope/focused ion beam dual-beam instrument. The samples were found to be ultra-fine grained. Nanoindentation hardness measurements of the surface layer showed a clear linear trend between the laser power density in the applied range and the measured hardness. Additional microhardness measurements suggest an annealed region beneath the surface.
Photocatalytic activity of MnWO4 powder in highly effective hydrogen generation from H2O and H2O2
Authors: He Hai Yan , Chen Ping
Published: March 2012

Hydrogen gas is a clear energy resource. The hydrogen generation from the H2O/H2O2/MnWO4 system was studied for the first time. The MnWO4 powders were fabricated via an aqueous reaction method and followed by calcination at 400°C. The powders were characterized with X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectrometry. The efficiency of the hydrogen generation increased with increasing initial pH in the appropriate range, H2O2 proportion, MnWO4 proportion, and intensity of light resource. Calcining at 400°C for 1 h makes the MnWO4 powder more effective for H2 generation and more stable at higher initial pH. The MnWO4 catalyst showed a long-term stability for photocatalytic H2 generation. A mechanism of the hydrogen generation from the H2O/H2O2/MnWO4 system is suggested.
Thermodynamics of dilute binary solid solutions using the cluster variation method
Authors: Sarma Bandikatla N. , Shah Shreyansh N. , Kumar Manoj , Lele Shrikant
Published: March 2012

A transformation of correlation functions used in the cluster variation method is introduced, such that the transformed correlation functions represent departures of the untransformed correlation functions from their values corresponding to ideal solutions. Analytical solutions for the transformed correlation functions and their derivatives with respect to composition in the infinite dilution limit are obtained for the first time for disordered binary bcc (under irregular tetrahedron approximation), fcc, and cph (both under tetrahedron-octahedron approximation) phases using the framework of the cluster variation method. These results are utilized to obtain the configurational contribution to self-interaction coefficients which occur in the expansion of the logarithm of the activity coefficient.
Phase equilibria in the Gd–Ni binary and Mg–Ni–Gd ternary systems
Authors: Xu Guanglong , Cui Yu-Wen , Fei Houjun , Zhang Ligang , Zheng Feng , Liu Libin , Jin Zhanpeng
Published: March 2012

Phase equilibria of the Gd–Ni binary and Mg–Ni–Gd ternary systems were critically investigated using equilibrated alloys and differential scanning calorimeter measurements. The phase diagram of the Gd–Ni binary system was updated from scanning electron microscopy with energy-dispersive X-ray spectrometry, X-ray diffraction, and differential scanning calorimeter results obtained on binary samples over the entire composition range. Major changes made in the present work include the absence of the Gd3Ni2and GdNi4compounds and the congruent melting point of the GdNi compound. An isothermal section of the Mg–Ni–Gd ternary system at 673 K was constructed from the investigations on 22 ternary alloys. In total, six ternary compounds were identified in this work, three of which were observed to crystallize in the Cu4MgSn (τ1), Mo2FeB2(τ2), and Ru4Al3B2-type (τ3) structures, respectively. As in most of the Mg–rare-earth metal–transition metal ternary systems, a long-period-stacking ordered phase was identified to have an 18R structure and a melting temperature of 806 K. Noticeable solid solubility of Ni in the Mg5Gd and Mg3Gd binary compounds was observed.
Solidification behaviour of an AA5754 Al alloy ingot cast with high impurity content
Authors: Kumar Sundaram , Babu Nadendla Hari , Scamans Geoff M. , Eskin Dmitry G. , Fan Zhongyun
Published: March 2012

In view of the recycling of aluminium scrap for automotive sheet application, we have investigated the solidification behaviour of AA5754 alloy containing additional amounts of impurity elements such as Si, Fe, and Cu. Ingot casts with a high impurity content resulted in coarse α-Al dendrites and complex-shaped secondary phases. A large volume of coarse Chinese script and needle-type Fe-bearing intermetallic phases were observed to form at the centre of an ingot. In addition to the grain-boundary eutectic, spherically shaped rosette-type eutectic phases were observed within the Al grain in the high-impurity alloy. The more uniform size distribution of the Fe-bearing intermetallics observed in the Al–Ti–B grain refined alloy is attributed to the presence of a large fraction of α-Al grain boundaries which distributes the eutectic liquid where the Fe-bearing intermetallic forced to nucleate and grow.
Thermal stability of coherent Pd/TiAl interfaces studied from first-principles calculations and experiments
Authors: Wang F. , Gong H. R.
Published: March 2012

Both first-principles molecular-dynamics calculations and experimental observations reveal that the coherent Pd/TiAl interfaces with various orientations are all thermally stable after annealing at 773 K, which seems good for the lifetime of Pd/TiAl membranes. It is found that the bond strength of the Pd/TiAl interface at 773 K becomes slightly smaller than the corresponding value at 0 K, and the interface dipole formed at 773 K seems marginally smaller than that at 0 K. In addition, calculations also show that the bond lengths of Pd/TiAl interfaces after annealing at 773 K become oscillated due to thermal vibrations, which are quite different from those at 0 K.
Controlled release of ofloxacin from gelatin blended with cloisite 30B
Authors: Sahoo Debasish , Nayak Padma Lochan
Published: March 2012

Gelatin–Cloisite 30B (C 30B) hybrid nano-composites were prepared by blending gelatin with cloisite 30B in aqueous solution. The nano-composites were characterized by using FTIR, SEM and XRD analysis. From the FTIR spectra the various groups present in the gelatin blend were monitored. The homogeneity, morphology and crystallinity of the blends were ascertained from SEM and XRD data, respectively. The results indicate that an intercalated or partially exfoliated nano-composite can be achieved, and the properties of the composite are significantly improved. The drug release kinetics was investigated using ofloxacin as the drug. The kinetics of the drug delivery system was systematically studied. Drug release kinetics was analyzed by plotting the cumulative release data vs. time by fitting to an exponential equation which indicates the non-Fickian type of kinetics. The drug release was investigated at different pH medium and it was found that the drug release depends upon the pH medium as well as the nature of the matrix.
Absorbable anterior cervical plate for corpectomy and fusion in a 2-year-old child with neurofibromatosis
Authors: Lidar Zvi , Constantini Shlomi , Regev Gilad J. , Salame Khalil
Published: March 2012

Postlaminectomy cervical kyphosis is one of the most challenging entities in spine surgery. Correction of this deformity usually requires anterior fusion with plating and a strut graft or interbody cage and posterior fusion with screws and rods. The situation is more complicated in the young child because fusion may affect future growth of the cervical spine. There is also a paucity of adequate instrumentation for the small bony structures. Some authors have reported utilization of absorbable cervical plates for fusion in pediatric patients with favorable results.

The authors present a modified surgical technique that was used for circumferential fusion in a 2-year-old girl with cervical kyphosis and recurrent neurofibroma. Anterior fusion was performed using an autologous rib graft and an absorbable cervical plate. This was followed by posterior fusion using rib bone and cables. Previous reports on the use of absorbable cervical plates are reviewed and the advantages of the current technique are discussed.