bluuebunny/crossref_metadata_2025 huggingface dataset:
Review of existing terrestrial bioaccumulation models and terrestrial bioaccumulation modeling needs for organic chemicals
Authors: Gobas Frank APC , Burkhard Lawrence P , Doucette William J , Sappington Keith G , Verbruggen Eric MJ , Hope Bruce K , Bonnell Mark A , Arnot Jon A , Tarazona Jose V
Published: August 2015

Protocols for terrestrial bioaccumulation assessments are far less-developed than for aquatic systems. This article reviews modeling approaches that can be used to assess the terrestrial bioaccumulation potential of commercial organic chemicals. Models exist for plant, invertebrate, mammal, and avian species and for entire terrestrial food webs, including some that consider spatial factors. Limitations and gaps in terrestrial bioaccumulation modeling include the lack of QSARs for biotransformation and dietary assimilation efficiencies for terrestrial species; the lack of models and QSARs for important terrestrial species such as insects, amphibians and reptiles; the lack of standardized testing protocols for plants with limited development of plant models; and the limited chemical domain of existing bioaccumulation models and QSARs (e.g., primarily applicable to nonionic organic chemicals). There is an urgent need for high-quality field data sets for validating models and assessing their performance. There is a need to improve coordination among laboratory, field, and modeling efforts on bioaccumulative substances in order to improve the state of the science for challenging substances. Integr Environ Assess Manag 2016;12:123–134. © 2015 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC.

Key Points

The report reviews models available for assessing the bioaccumulation potential of organic compounds in terrestrial food webs. Major limitations in terrestrial bioaccumulation modeling include the lack of QSARs for biotransformation and dietary assimilation efficiencies for terrestrial species, and the lack of models and QSARs for important terrestrial species such as insects, amphibians and reptiles. Other limitations include the limited chemical domain of existing bioaccumulation models and QSARs, and the lack of standardized testing protocols for plants that has limited development of plant models.
A case study for evaluating potential soil sensitivity in aridland systems
Authors: Peterman Wendy L , Ferschweiler Ken
Published: August 2015

Globally, ecosystems are subjected to prolonged droughts and extreme heat events, leading to forest die-offs and dominance shifts in vegetation. Some scientists and managers view soil as the main resource to be considered in monitoring ecosystem responses to aridification. As the medium through which precipitation is received, stored, and redistributed for plant use, soil is an important factor in the sensitivity of ecosystems to a drying climate. This study presents a novel approach to evaluating where on a landscape soils may be most sensitive to drying, making them less resilient to disturbance, and where potential future vegetation changes could lead to such disturbance. The drying and devegetation of arid lands can increase wind erosion, contributing to aerosol and dust emissions. This has implications for air quality, human health, and water resources. This approach combines soil data with vegetation simulations, projecting future vegetation change, to create maps of potential areas of concern for soil sensitivity and dust production in a drying climate. Consistent with recent observations, the projections show shifts from grasslands and woodlands to shrublands in much of the southwestern region. An increase in forested area occurs, but shifts in the dominant types and spatial distribution of the forests also are seen. A net increase in desert ecosystems in the region and some changes in alpine and tundra ecosystems are seen. Approximately 124 000 km2 of soils flagged as “sensitive” are projected to have vegetation change between 2041 and 2050, and 82 927 km2 of soils may become sensitive because of future vegetation changes. These maps give managers a way to visualize and identify where soils and vegetation should be investigated and monitored for degradation in a drying climate, so restoration and mitigation strategies can be focused in these areas. Integr Environ Assess Manag 2016;12:388–396. © 2015 SETAC

Key Points

Maps can be made to indicate where on the landscape soils are inherently sensitive to drying conditions. Vegetation simulations can help identify areas of the landscape where vegetation is likely to change in the future. The combination of vegetation change projections and soil sensitivity maps can indicate where on the landscape sensitive soils may be disturbed in a drying climate. Using these maps, managers can identify areas on the landscape where it would be most beneficial to allocate monitoring and mitigation strategies for soil erosion and dust emissions.
A statistical evaluation of the safety factor and species sensitivity distribution approaches to deriving environmental quality guidelines
Authors: Zajdlik Barry Alan
Published: August 2015

The species sensitivity distribution (SSD) distribution approach to estimating water quality guidelines (WQGs) is the preferred method in all jurisdictions reviewed (Australia, Canada, New Zealand, Organisation for Economic Co-operation and Development [OECD] members, South Africa, United States) and is one of the recommended methods for European Commission members for 33 priority and priority hazardous substances. In the event that jurisdiction-specific criteria for data quality, quantity, and taxonomic representation are not met, all of these jurisdictions endorse the use of additional safety factors (SFs) applied to either the SSD-based WQG or, the lowest suitable toxicity test endpoint. In Canada, the British Columbia Ministry of Environment endorses this latter approach as the preferred approach in the belief that so-derived WQGs are more protective than SSD-based WQGs. The level of protection afforded by the latter SF approach was evaluated by statistically sampling minima from random samples of the following distributions: normal, Gumbel, logistic, and Weibull, using a range of coefficients of variation (cVs) and applying the SFs of 2 or 10 used in British Columbia. The simulations indicate that the potentially affected fraction of species (PAF) can be as high as 20%, or, approach 0%. The PAF varies with sample size and CV. Because CVs can vary systematically with mode of toxic action, the PAF using SF-based WQGs can also vary systematically with analyte class. The varying levels of protection afforded by SF-based WQGs are generally inconsistent with the common water quality management goal that allows for a small degree of change under long-term exposure. The findings suggest that further efforts be made to develop high-quality WQGs that support informed decision making and are consistent with the environmental management goal instead of using SFs in the hope of achieving an acceptable but unknown, degree of environmental protection. Integr Environ Assess Manag 2016;12:380–387. © 2015 SETAC

Key Points

Application of safety factors to the “lowest available” toxicity test endpoint is either preferred or fall-back method for estimating environmental quality guidelines. It is believed that the safety factor method is more protective than other methods such as using the 5th percentile of a species sensitivity distribution. The level of protection using the safety factor method is inconsistent, varying with dataset sample size, degree of variability, and the underlying statistical distribution of the toxicity test endpoint. The safety factor approach can protect (as a limit) 100% of species or less than 55% of species.
Acute severe organophosphate poisoning in a child who was successfully treated with therapeutic plasma exchange, high‐volume hemodiafiltration, and lipid infusion
Authors: Yesilbas Osman , Kihtir Hasan S. , Altiti Mohammad , Petmezci Mey Talip , Balkaya Seda , Bursal Duramaz Burcu , Ersoy Melike , Sevketoglu Esra
Published: August 2015

Acute severe organophosphate poisoning is a serious complication seen in developing and agricultural countries. Pralidoxime and high dose atropine are the standard treatments. There is no consensus about acute severe organophosphate poisonings that are unresponsive to pralidoxime, atropine, and supportive therapies. We report a case of acute severe organophosphate poisoning that was unresponsive to standard treatments and successfully treated with high‐volume continuous venovenous hemodiafiltration and therapeutic plasma exchange combined with lipid infusion. J. Clin. Apheresis 31:467–469, 2016. © 2015 Wiley Periodicals, Inc.
Thrombotic thrombocytopenic purpura in a postoperative patient taking cephalexin responding to plasmapheresis: A case report and review of cephalosporin‐induced TTP
Authors: Patel Ritu , Amber Kyle T.
Published: August 2015

The clinical presentation of thrombotic thrombocytopenic purpura (TTP) is often atypical delaying diagnosis and treatment. A number of drugs have been implicated in the development of TTP, including cyclosporine, tacrolimus, clopidogrel, and quinine. To our knowledge, only three cases of cephalosporin‐induced TTP have been described, with two of these cases occurring with these use of cephalexin. We herein describe a case of TTP occurring in a postoperative patient taking cephalexin, requiring plasmapheresis. Following plasmapheresis, the patient's mental status and platelet count significantly improved. J. Clin. Apheresis 31:473–475, 2016. © 2015 Wiley Periodicals, Inc.
Mixed Oxides FeVOx for Selective Oxidation of Octanol to Octanal under Solvent‐free Condition
Authors: Zhang Hongyu , Lu Bin , You Xuelin , Ma Fengyu , Zhao Jingxiang , Cai Qinghai
Published: August 2015

The two‐component mixed oxides FeVOx with various molar ratio of Fe to V were prepared and their phase composition, structure and morphology were determined by XRD and SEM. This prepared material was employed for liquid‐phase oxidation of octanol using H2O2 as oxidant. The mixed oxide FeVOx with 2.5 : 1 of Fe to V molar ratio was found to be an effective catalyst with high selectivity to octanal under solvent‐free condition. The relationship between the catalytic performance and phase compositions of the mixed oxides was investigated by the test of its activity and XRD characterization. The catalytic action of the active sites including redox and acidic sites formed by interaction between VOx and FeOx on the surface of the catalyst was discussed. The catalyst was easily recovered and reused.
Synthesis, Spectroscopy, Semi‐empirical and Biological Activities of Organotin(IV) Complexes with o‐Isopropyl Carbonodithioic Acid
Authors: Javed Fatima , Ali Saqib , Shahzadi Saira , Khalid Nasir , Tabassum Saira , Khan Imran , Sharma Saroj K. , Qanungo Kushal
Published: August 2015

New organotin(IV) complexes have been synthesized by treating potassium o‐isopropyl carbonodithioate with R2SnCl2/R3SnCl in 1 : 2/1 : 1 M/L ratio. All complexes have been characterized by IR and NMR (1H, 13C) spectroscopy. IR results shows that ligand acts as bidentate which is also confirmed by semi‐empirical study. NMR data reveals four coordinated geometry in solution. Computed positive heat of formation shows that complex 5 is thermodynamically unstable. UV/visible spectroscopy was used to assess the mode of interaction and binding of the complexes with DNA which shows that complex 5 exhibits higher binding constant as compared to complex 3. In protein kinase inhibition assay, compound 3 was found most active, while other biological activities shows that triorganotin(IV) complexes are biologically more active as compared to diorganotin(IV) complexes.
Exploratory effects of a strong CYP3A inhibitor (ketoconazole), a strong CYP3A inducer (rifampicin), and concomitant ethanol on piragliatin pharmacokinetics and pharmacodynamics in type 2 diabetic patients
Authors: Zhi Jianguo , Zhai Suoping , Georgy Angela , Liang Zhenming , Boldrin Mark
Published: August 2015

Piragliatin is a CYP3A substrate; its inactive metabolite M4, formed through cytosolic reductase, is reversibly metabolized back to piragliatin through CYP3A. The impact of concomitant CYP3A modifiers thus cannot be predicted. Drinking alcohol under fasting conditions is associated with a recognized glucose‐lowering effect, which might be synergistic with piragliatin's hypoglycemic effect. Two exploratory studies were conducted to examine these potential interactions in type 2 diabetes (T2D) patients: 16 completed an open‐label, sequential 2‐way crossover, 2‐arm (randomized to ketoconazole and rifampicin) CYP3A study; another 18 participated in a double‐blind, placebo‐controlled, randomized 3‐way crossover ethanol study. Administration of piragliatin (100‐mg single dose) resulted in a 32% Cmax and 44% area under the curve (AUC∞) increase in piragliatin exposure without affecting glucose AUC0‐6h following ketoconazole (400 mg QD × 5 days); 30% Cmax and 72% AUC∞ decrease in piragliatin exposure with a 13% increase in glucose AUC0‐6h following rifampicin (600 mg QD × 5 days); and, unexpectedly, a 32% Cmax and 23% AUC0‐6h decrease (no change in AUC∞) in piragliatin exposure with a 13% increase in glucose AUC0‐6h following alcohol (40‐g single dose). In conclusion, a strong CYP3A modifier or concomitant alcohol could lead to a change in exposure to piragliatin with a potential alteration in glucose‐lowering effect.
What Makes Rural Co‐operatives Resilient in Developing Countries?
Authors: Borda‐Rodriguez Alexander , Johnson Hazel , Shaw Linda , Vicari Sara
Published: August 2015

It has been argued that current interest in co‐operatives is because they can reduce poverty and are resilient organisations. However, histories of co‐operatives' successes and failures suggest that co‐operative organisational resilience needs better understanding. This article reviews the literature, particularly with respect to sub‐Saharan Africa. It argues that co‐operative organisational resilience centres on co‐operatives' multidimensionality and the development of collective capability in five mutually reinforcing areas of activity. These are membership, networks, collective skills in governance, innovation and engagement with governments. Together, they strengthen co‐operatives' resilience, but where lacking, they undermine it. The article adds to thinking about ‘co‐operative advantage’. Copyright © 2015 John Wiley & Sons, Ltd.
Diffusion tensor imaging and T2 mapping in early denervated skeletal muscle in rats
Authors: Ha Dong‐Ho , Choi Sunseob , Kang Eun‐Ju , Park Hwan Tae
Published: August 2015

Background

To evaluate the temporal changes of diffusion tensor imaging (DTI) indices, T2 values, and visual signal intensity on various fat suppression techniques in the early state of denervated skeletal muscle in a rat model.

Methods

Institutional Animal Care and Use Committee approval was obtained. Sciatic nerves of eight rats were transected for irreversible neurotmesis model. We examined normal lower leg and denervated muscles at 3 days, 1 week, and 2 weeks on a 3 Tesla MR. fractional anisotropy (FA), mean apparent diffusion coefficient (mADC), and T2 values were measured by using DTI and T2 mapping scan. We subjectively classified the signal intensity change on various fat suppression images into the following three grades: negative, suspicious, and definite change. Wilcoxon‐sign rank test and Kruskal‐Wallis test were used for the comparison of FA, mADC, T2 values. McNemar's test was used for comparing signal intensity change among fat suppression techniques.

Results

FA values of denervated muscles at 3 days (0.35 ± 0.06), 1 week (0.29 ± 0.04), and 2 weeks (0.34 ± 0.05) were significantly (P < 0.05) lower than that in the control group (0.54 ± 0.17). mADC of denervated muscles decreased without statistically significant (P > 0.05) change. T2 values were significantly increased at 1 week (38.11 ± 6.42 ms, P = 0.017) and markedly increased at 2 weeks (46.53 ± 5.17 ms, P = 0.012). The grade of visual signal intensity change on chemical shift selective fat saturation, STIR and IDEAL images were identical in all cases (P = 1.000).

Conclusion

FA and T2 values can demonstrate the early temporal changes in denervated rat skeletal muscle. J. Magn. Reson. Imaging 2015;42:617–623
The importance of the proximal resection margin distance for proximal gastric adenocarcinoma: A multi‐institutional study of the US Gastric Cancer Collaborative
Authors: Postlewait Lauren M. , Squires Malcolm H. , Kooby David A. , Poultsides George A. , Weber Sharon M. , Bloomston Mark , Fields Ryan C. , Pawlik Timothy M. , Votanopoulos Konstantinos I. , Schmidt Carl R. , Ejaz Aslam , Acher Alexandra W. , Worhunsky David J. , Saunders Neil , Swords Douglas , Jin Linda X. , Cho Clifford S. , Winslow Emily R. , Cardona Kenneth , Staley Charles A. , Maithel Shishir K.
Published: August 2015

Background

A 5 cm margin is advocated for distal gastric adenocarcinoma (GAC). The optimal proximal resection margin (PM) length for proximal GAC is not established.

Methods

Patients who underwent curative‐intent resection for proximal GAC from 2000 to 2012 at 7 centers in the US Gastric Cancer Collaborative were included. PM length was sequentially dichotomized and analyzed at 0.5 cm increments (0.5–6.5 cm). Outcomes after negative margin (R0) and positive microscopic margin (R1) resections were compared. Primary endpoints were local recurrence (LR) and overall survival (OS).

Results

All patients (n = 162) had R0 distal margins. 151 (93.2%) had an R0‐PM with mean length of 2.6 cm (median:1.7 cm; range:0.1–15 cm). A greater PM distance was not associated with LR or OS. An R1‐PM was associated with higher N‐stage (N3:73% vs. 26%; P = 0.007) and increased LR (HR6.1; P = 0.009) but not associated with decreased OS. On multivariate analysis, an R1‐PM was also not independently associated with LR.

Conclusions

For resection of proximal gastric adenocarcinoma, proximal margin length is not associated with local recurrence or overall survival. An R1 margin is associated with advanced N‐stage but is not independently associated with recurrence or survival. When performing resection of proximal gastric adenocarcinoma, efforts to achieve a specific margin distance, especially if it necessitates an esophagectomy, should be abandoned. J. Surg. Oncol. 2015 111:203–207. © 2015 Wiley Periodicals, Inc.
A Web‐Based Early Intervention Can Prevent Long‐Term PTS Reactions in Children With High Initial Distress Following Accidental Injury
Authors: Kenardy Justin A. , Cox Catherine M. , Brown Felicity L.
Published: August 2015

The present study explored the targeting of a preventative information provision intervention delivered to children following accidental injury by assessing the impact of initial traumatic distress on response to treatment. Analyses were based on baseline and 6‐month outcome of child traumatic stress in a control (n = 28) and an intervention group (n = 31). Moderation of treatment outcome by initial levels of child traumatic stress was assessed through multiple hierarchical regression analyses. Results indicated the interaction between treatment provision and initial level of posttraumatic stress significantly predicted 6‐month outcome (β = −.42, p = .019). When initial distress was high, children in the control group demonstrated an increase in trauma symptoms, and had significantly higher trauma symptoms at follow‐up than those in the treatment group (d = 0.94, p = .008). When initial distress was not elevated, no significant differences were noted between the groups. These results indicate that a preventative early intervention may be best targeted at children presenting with the specific risk factor of high initial distress.
Spatiotemporal variation in the distribution of potential predators of a resource pulse: Black bears and caribou calves in Newfoundland
Authors: Rayl Nathaniel D. , Fuller Todd K. , Organ John F. , Mcdonald John E. , Otto Robert D. , Bastille‐Rousseau Guillaume , Soulliere Colleen E. , Mahoney Shane P.
Published: August 2015

Understanding spatiotemporal variability in prey accessibility is important for disentangling predator‐prey interactions and is relevant to management interventions to reduce predation. Recently, caribou (Rangifer tarandus) in Newfoundland declined by 66%, with calf predation by black bears (Ursus americanus) implicated as a major proximate mechanism of the decline. Most predation occurs when calves are aggregated on calving grounds. We used telemetry data from 271 caribou and 45 black bears in 2 caribou herd ranges to examine spatial variability in calf accessibility, identify the distribution of potentially predatory bears, and assess the aggregative response of bears to the calf resource. We predicted whether a bear was a visitor to a calving ground during the calving season (a potentially predatory bear) based upon its sex, the herd range it occupied, its distance to the calving grounds, and the season. The distribution of potentially predatory bears and their degree of segregation from non‐predatory bears varied seasonally. The probability of a bear visiting the calving grounds during calving decreased with increasing distance from the calving grounds, and was greater for males than for females in all seasons at distances beyond 2.4 km from the calving grounds. Residency time of bears increased in the calving grounds of 1 herd during calving, suggesting an aggregative response to neonates in that area. For both herds, the estimated distribution of potentially predatory bears was much larger than the calving grounds, illustrating that the relevant scale of predator‐prey interactions may extend far beyond the area where lethal encounters occur. Our work highlights the value of examining spatiotemporal dynamics of predator movements prior to implementing ecosystem manipulations designed to reduce predation and provides a modeling framework that can be used to guide management interventions in systems with aggregated prey. © 2015 The Wildlife Society.
Combining waterfowl and breeding bird survey data to estimate wood duck breeding population size in the Atlantic Flyway
Authors: Zimmerman Guthrie S. , Sauer John R. , Fleming Kathy , Link William A. , Garrettson Pamela R.
Published: August 2015

We combined data from the Atlantic Flyway Breeding Waterfowl Survey (AFBWS) and the North American Breeding Bird Survey (BBS) to estimate the number of wood ducks (Aix sponsa) in the United States portion of the Atlantic Flyway from 1993 to 2013. The AFBWS is a plot‐based survey that covers most of the northern and central portions of the Flyway; when analyzed with adjustments for survey time of day effects, these data can be used to estimate population size. The BBS provides an index of wood duck abundance along roadside routes. Although factors influencing change in BBS counts over time can be controlled in BBS analysis, BBS indices alone cannot be used to derive population size estimates. We used AFBWS data to scale BBS indices for Bird Conservation Regions (BCR), basing the scaling factors on the ratio of estimated AFBWS population sizes to regional BBS indices for portions of BCRs that were common to both surveys. We summed scaled BBS results for portions of the Flyway not covered by the AFBWS with AFBWS population estimates to estimate a mean yearly total of 1,295,875 (mean 95% CI: 1,013,940–1,727,922) wood ducks. Scaling factors varied among BCRs from 16.7 to 148.0; the mean scaling factor was 68.9 (mean 95% CI: 53.5–90.9). Flyway‐wide, population estimates from the combined analysis were consistent with alternative estimates derived from harvest data, and also provide population estimates within states and BCRs. We recommend their use in harvest and habitat management within the Atlantic Flyway. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Microhabitat comparison of swamp rabbit sites between periphery and core of the species range
Authors: Dumyahn Joseph B. , Zollner Patrick A. , Smith Winston P.
Published: August 2015

Swamp rabbits (Sylvilagus aquaticus) inhabit bottomland hardwood forests and rely on key microhabitat features found in this forested wetland system. Research comparing key features of swamp rabbit habitat across the species' geographic range is lacking. In this study, we compared 13 microhabitat characteristics at sites associated with 2 distinct behaviors (form and latrine) of swamp rabbits at the northern extent of their distribution (southwest Indiana, northwest Kentucky) with sites from the species' core distribution (Arkansas). There were significant differences in vegetation structure including canopy cover, basal area, stand density, and stem density between Indiana, Kentucky, and Arkansas sites for both form and latrine locations. At the northern periphery, where swamp rabbit populations are of conservation concern, we found that habitat is composed of fewer key components that are ecologically important to swamp rabbits such as canopy gaps, downed woody material, and cover. Wildlife managers interested in providing swamp rabbit habitat should recognize microhabitat components (i.e., canopy gaps, downed woody material) that are favorable for swamp rabbits and attempt to supply these elements through management actions such as uneven‐aged silvicultural practices. © 2015 The Wildlife Society.
Habitat manipulation influences northern bobwhite resource selection on a reclaimed surface mine
Authors: Brooke Jarred M. , Peters David C. , Unger Ashley M. , Tanner Evan P. , Harper Craig A. , Keyser Patrick D. , Clark Joseph D. , Morgan John J.
Published: August 2015

More than 600,000 ha of mine land have been reclaimed in the eastern United States, providing large contiguous tracts of early successional vegetation that can be managed for northern bobwhite (Colinus virginianus). However, habitat quality on reclaimed mine land can be limited by extensive coverage of non‐native invasive species, which are commonly planted during reclamation. We used discrete‐choice analysis to investigate bobwhite resource selection throughout the year on Peabody Wildlife Management Area, a 3,330‐ha reclaimed surface mine in western Kentucky. We used a treatment‐control design to study resource selection at 2 spatial scales to identify important aspects of mine land vegetation and whether resource selection differed between areas with habitat management (i.e., burning, disking, herbicide; treatment) and unmanaged units (control). Our objectives were to estimate bobwhite resource selection on reclaimed mine land and to estimate the influence of habitat management practices on resource selection. We used locations from 283 individuals during the breeding season (1 Apr–30 Sep) and 136 coveys during the non‐breeding season (1 Oct–Mar 31) from August 2009 to March 2014. Individuals were located closer to shrub cover than would be expected at random throughout the year. During the breeding season, individuals on treatment units used areas with smaller contagion index values (i.e., greater interspersion) compared with individuals on control units. During the non‐breeding season, birds selected areas with greater shrub‐open edge density compared with random. At the microhabitat scale, individuals selected areas with increased visual obstruction >1 m aboveground. During the breeding season, birds were closer to disked areas (linear and non‐linear) than would be expected at random. Individuals selected non‐linear disked areas during winter but did not select linear disked areas (firebreaks) because they were planted to winter wheat each fall and lacked cover during the non‐breeding season. Individuals also selected areas treated with herbicide to control sericea lespedeza (Lespedeza cuneata) throughout the year. During the breeding season, bobwhites avoided areas burned during the previous dormant season. Habitat quality of reclaimed mine lands may be limited by a lack of shrub cover and extensive coverage of non‐native herbaceous vegetation. Managers aiming to increase bobwhite abundance should focus on increasing interspersion of shrub cover, with no area >100 m from shrub cover. We suggest disking and herbicide application to control invasive species and improve the structure and composition of vegetation for bobwhites. © 2015 The Wildlife Society.
Nonlinear eigenvalue problems for quasilinear equations in unbounded domains
Authors: Drábek Pavel , Simader Christian G.
Published: August 2015

We prove the existence of a solution of the nonlinear equation

in IRN and in exterior domains, respectively. We concentrate to the case when p ≥ N and the nonlinearity f(x, · ) is “superlinear” and “subcritical”.
Toric rings generated by special stable sets of monomials
Authors: De Negri Emanuela
Published: August 2015

In this paper we consider some subalgebras of the d‐th Veronese subring of a polynomial ring, generated by stable subsets of monomials. We prove that these algebras are Koszul, showing that the presentation ideals have Gröbner bases of quadrics with respect to suitable term orders. Since the initial monomials of the elements of these Gröbner bases are square‐ free, it follows by a result of STURMFELS [S, 13.15], that the algebras under consideration are normal, and thus Cohen‐Macaulay.
Mixed boundary value problems for nonlinear elliptic equations in multidimensional non‐smooth domains
Authors: Ebmeyer Carsten , Frehse Jens
Published: August 2015

The nonlinear elliptic equation

is investigated. It is supposed that u fulfils a mixed boundary value condition and that Ω ⊂ IRn (n ≥ 3) has a piecewise smooth boundary. Ws,2 — regularity (s < 3/2) of u and Lp — properties of the first and the second derivatives of u are proven.
Coarse Geometry via Grothendieck Topologies
Authors: Schmidt Alexander
Published: August 2015

We show that the coarse cohomology, defined by J. ROE for complete metric spaces, coincides with the sheaf cohomology of the constant sheaf IR for a certain Grothendieck topology. Therefore many properties of coarse cohomology are easy consequences of general principles.
Sharp sobolev embeddings and related hardy inequalities: The critical case
Authors: Edmunds David E. , Triebel Hans
Published: August 2015

The paper deals with sharp embeddings of the Sobolev spaces Hsp(IRn) and the Besov spaces Bsp,p(IRn) into rearrangement—invariant spaces and related Hardy inequalities. Here 1 < p < ∞ and s = n/p.
Potential bounds in problems on quasilinear elliptic equations
Authors: Krasnosel'Skii Mark , Mennicken Reinhard , Rachinskii Dmitrii
Published: August 2015

We study quasilinear elliptic equations with strong nonlinear terms and systems of such equations. The methods developed by the authors in [1], [2] are used to prove the existence of solutions for boundary—value problems using some information on behavior of potential bounds for nonlinearities; the L–characteristics of elliptic operators and their fractional powers play an important role. New conditions are suggested for the existence of classical solutions of quasilinear second order elliptic equations.
On smooth rational threefolds of P5 with rational non—special hyperplane section
Authors: Mezzetti Emilia , Portelli Dario
Published: August 2015

It is known that the smooth rational threefolds of P5 having a rational non—special surface of P4 as general hyperplane section have degree d = 3, …, 7. We study such threefolds X from the point of view of linear systems of surfaces in P3, looking in each case for an explicit description of a birational map from P3 to X. For d = 3, … 6 we prove that there exists a line L on X such that the projection map of X centered at L is birational; we completely describe the base loci B of the linear systems found in this way and give a description of any such threefold X as a suitable blowing—down of the blowing—up of P3 along B. If d = 7, i.e., if X is a Palatini scroll, we prove that, conversely, a similar projection never exists.
Effect of aging parameters on the mechanical properties of naturally aged Al–Mg–Si alloy
Authors: Başer T. A.
Published: August 2015

Among the extruded products within the Al–Mg–Si system, AA6082 alloy is regarded as high strength alloy which is used for automotive structural applications. Room temperature storage in between the solution heat treatment and the paint bake cycle is unavoidable problem and undergoes natural aging. Hence, natural aging time in the conventional T4 condition must be modified after the solution heat treatment in order to avoid any hardening during storage before forming processes. The present work was investigated to improve paint bake response of extruded 6082 profiles by employing pre‐aging in between the solution heat treatment and the paint bake in order to obtain sufficient strength for the required in‐service dent resistance. Pre‐aging treatment was performed for 5 min at 180 °C, 200 °C and 225 °C to improve bake hardening response of extruded 6082 profiles. Tensile tests and micro hardness measurements are performed to determine the natural aging effect on mechanical properties. In order to understand the precipitation hardening of this aluminum profile with a different natural aging time, differential scanning calorimetry measurements are performed.
Constitutive modeling for the hot deformation behavior of Mg–3.06Zn–0.58Zr–1.07Y alloy
Authors: Chen B. D. , Guo F. , Wen J.
Published: August 2015

In order to improve the understanding flow behaviors of hot compressive deformation as‐homogenized of Mg–3.06Zn–0.58Zr–1.07Y alloy, carried out a series of isothermal compressive tests with 60% height reduction of specimens were performed at constant temperature of 523 K, 573 K, 623 K, 673 K, and 723 K, and strain rates of 0.001, 0.01, 0.1, and 1 s−1 on Gleeble‐1500 thermo‐mechanical simulator. The results of the true stress–strain curves show that the flow stress increases with the increasing strain rate and decreasing deformation temperature. The flow behavior at constant strain rate was characterized by the dynamic recrystallization and dynamic recovery softening mechanisms occur simultaneously. The number of the dynamic recrystallization curve increases with increasing strain rate. A nonlinear flow model and its constitutive equation, based on the Arrhenius‐type equation, were employed for studying the deformation behavior and relationships between the deformation temperature, strain rate, and flow stress. Finally, the processing map of Mg–3.06Zn–0.58Zr–1.07Y alloy at the strain of 0.3 was obtained through the dynamic materials modeling. The optimal processing temperature and strain rate, using the microstructure and constitutive modeling, were found to be in the rage 623–723 K and 0.1–1 s−1, respectively.
Ownership Concentration, Institutional Development and Firm Performance in Central and Eastern Europe
Authors: Balsmeier Benjamin , Czarnitzki Dirk
Published: August 2015

This paper analyzes the relationship of ownership concentration and firm performance in the context of different institutional environments in 28 Central and Eastern European transition economies. We focus on private, non‐listed firms that have been largely neglected by the extant literature. Using the BEEPS data for the period from 2002 to 2009 we find an inverted u‐shaped relation of ownership concentration and firm performance for those firms that operate in non‐EU‐member countries as well as those firms that are situated in less developed institutional systems. We interpret these findings as evidence for a classic agency problem in the lower part of the ownership concentration distribution that is dominated by a ‘private benefits of control’ problem with rising ownership concentration. Copyright © 2015 John Wiley & Sons, Ltd.
Nonpharmacological treatments for patients with Parkinson's disease
Authors: Bloem Bastiaan R. , de Vries Nienke M. , Ebersbach Georg
Published: August 2015

Since 2013, a number of studies have enhanced the literature and have guided clinicians on viable treatment interventions outside of pharmacotherapy and surgery. Thirty‐three randomized controlled trials and one large observational study on exercise and physiotherapy were published in this period. Four randomized controlled trials focused on dance interventions, eight on treatment of cognition and behavior, two on occupational therapy, and two on speech and language therapy (the latter two specifically addressed dysphagia). Three randomized controlled trials focused on multidisciplinary care models, one study on telemedicine, and four studies on alternative interventions, including music therapy and mindfulness. These studies attest to the marked interest in these therapeutic approaches and the increasing evidence base that places nonpharmacological treatments firmly within the integrated repertoire of treatment options in Parkinson's disease. © 2015 International Parkinson and Movement Disorder Society
Dynamic stress intensity factors of two 3D rectangular permeable cracks in a transversely isotropic piezoelectric material under a time‐harmonic elastic P‐wave
Authors: Liu Hai‐Tao , Zhou Zhen‐Gong
Published: August 2015

The dynamic behavior of two 3D rectangular permeable cracks in a transversely isotropic piezoelectric material is investigated under an incident harmonic stress wave by using the generalized Almansi's theorem and the Schmidt method. The problem is formulated through double Fourier transform into three pairs of dual integral equations with the displacement jumps across the crack surfaces as the unknown variables. To solve the dual integral equations, the displacement jumps across the crack surfaces are directly expanded as a series of Jacobi polynomials. Finally, the relations among the dynamic stress field and the dynamic electric displacement filed near the crack edges are obtained, and the effects of the shape of the rectangular crack, the characteristics of the harmonic wave, and the distance between two rectangular cracks on the stress and the electric intensity factors in a piezoelectric composite material are analyzed. Copyright © 2015 John Wiley & Sons, Ltd.
Comparing Health‐Care Providers' Perspectives on Complementary and Alternative Medicine in Childhood Cancer Between Netherlands and Indonesia
Authors: Gunawan Stefanus , Arnoldussen Marijn , Gordijn Maartje S. , Sitaresmi Mei N. , van de Ven Peter M. , ten Broeke Chloé A.M. , Veerman Anjo J.P. , Mantik Max , Kaspers Gertjan J.L. , Mostert Saskia
Published: August 2015

Background

Use of complementary and alternative medicine (CAM) is common among patients with childhood cancer. Health‐care providers (HCP) should address this need properly. Geographical and cultural differences seem likely. This study explores perspectives on CAM of HCP involved in the care of children with cancer in Netherlands and Indonesia. Health beliefs, components of CAM, encouraging or discouraging CAM, and knowledge about CAM were assessed.

Procedure

We conducted a cross‐sectional study using semi‐structured questionnaires at a Dutch and Indonesian academic hospital.

Results

A total of 342 HCP participated: 119 Dutch (response rate 80%) and 223 Indonesian (response rate 87%). Chemotherapy can cure cancer according to more Dutch than Indonesian HCP (87% vs. 53% respectively, P < 0.001). Combination of chemotherapy and CAM is the best way to cure cancer according to more Indonesian than Dutch HCP (45% vs. 25%, P < 0.001). Dutch and Indonesian HCP recommend and discourage CAM use differently. Most Dutch (77%) and Indonesian HCP (84%) consider their knowledge about CAM to be inadequate (P = ns). Fewer Dutch doctors than other HCP want to learn more about CAM (51% vs. 76%, P = 0.007), whereas there is no significant difference in eagerness to learn about CAM between Indonesian doctors (64%) and other HCP (72%).

Conclusions

Indonesian HCP have more positive views about CAM than their Dutch colleagues. Both Dutch and Indonesian HCP consider their knowledge about CAM to be inadequate. Therefore, education programs about CAM tailored to the needs of HCP are recommended, knowing that CAM is used frequently. Pediatr Blood Cancer © 2015 Wiley Periodicals, Inc.
Hydroxyurea Therapy for Children With Sickle Cell Anemia in Sub‐Saharan Africa: Rationale and Design of the REACH Trial
Authors: McGann Patrick T. , Tshilolo Léon , Santos Brigida , Tomlinson George A. , Stuber Susan , Latham Teresa , Aygun Banu , Obaro Stephen K. , Olupot‐Olupot Peter , Williams Thomas N. , Odame Isaac , Ware Russell E. ,   for the REACH Investigators
Published: August 2015

Background

Sickle cell anemia (SCA) is an inherited hematological disorder that causes a large but neglected global health burden, particularly in Africa. Hydroxyurea represents the only available disease‐modifying therapy for SCA, and has proven safety and efficacy in high‐resource countries. In sub‐Saharan Africa, there is minimal use of hydroxyurea, due to lack of data, absence of evidence‐based guidelines, and inexperience among healthcare providers.

Procedure

A partnership was established between investigators in North America and sub‐Saharan Africa, to develop a prospective multicenter research protocol designed to provide data on the safety, feasibility, and benefits of hydroxyurea for children with SCA.

Results

The Realizing Effectiveness Across Continents with Hydroxyurea (REACH, ClinicalTrials.gov NCT01966731) trial is a prospective, phase I/II open‐label dose escalation study of hydroxyurea that will treat a total of 600 children age 1–10 years with SCA: 150 at each of four different clinical sites within sub‐Saharan Africa (Angola, Democratic Republic of Congo, Kenya, and Uganda). The primary study endpoint will be severe hematological toxicities that occur during the fixed‐dose treatment phase. REACH has an adaptive statistical design that allows for careful assessment of toxicities to accurately identify a safe hydroxyurea dose.

Conclusions

REACH will provide data that address critical gaps in knowledge for the treatment of SCA in sub‐Saharan Africa. By developing local expertise with the use of hydroxyurea and helping to establish treatment guidelines, the REACH trial results will have the potential to transform care for children with SCA in Africa. Pediatr Blood Cancer © 2015 Wiley Periodicals, Inc.
Protein dynamics and the all‐ferrous [Fe4S4] cluster in the nitrogenase iron protein
Authors: Tan Ming‐Liang , Perrin B. Scott , Niu Shuqiang , Huang Qi , Ichiye Toshiko
Published: August 2015

In nitrogen fixation by Azotobacter vinelandii nitrogenase, the iron protein (FeP) binds to and subsequently transfers electrons to the molybdenum–FeP, which contains the nitrogen fixation site, along with hydrolysis of two ATPs. However, the nature of the reduced state cluster is not completely clear. While reduced FeP is generally thought to contain an [Fe4S4]1+ cluster, evidence also exists for an all‐ferrous [Fe4S4]0 cluster. Since the former indicates a single electron is transferred per two ATPs hydrolyzed while the latter indicates two electrons could be transferred per two ATPs hydrolyzed, an all‐ferrous [Fe4S4]0 cluster in FeP is potenially two times more efficient. However, the 1+/0 reduction potential has been measured in the protein at both 460 and 790 mV, causing the biological significance to be questioned. Here, “density functional theory plus Poisson Boltzmann” calculations show that cluster movement relative to the protein surface observed in the crystal structures could account for both measured values. In addition, elastic network mode analysis indicates that such movement occurs in low frequency vibrations of the protein, implying protein dynamics might lead to variations in reduction potential. Furthermore, the different reductants used in the conflicting measurements of the reduction potential could be differentially affecting the protein dynamics. Moreover, even if the all‐ferrous cluster is not the biologically relevant cluster, mutagenesis to stabilize the conformation with the more exposed cluster may be useful for bioengineering more efficient enzymes.
Hfqs in Bacillus anthracis: Role of protein sequence variation in the structure and function of proteins in the Hfq family
Authors: Vrentas Catherine , Ghirlando Rodolfo , Keefer Andrea , Hu Zonglin , Tomczak Aurelie , Gittis Apostolos G. , Murthi Athulaprabha , Garboczi David N. , Gottesman Susan , Leppla Stephen H.
Published: August 2015

Hfq proteins in Gram‐negative bacteria play important roles in bacterial physiology and virulence, mediated by binding of the Hfq hexamer to small RNAs and/or mRNAs to post‐transcriptionally regulate gene expression. However, the physiological role of Hfqs in Gram‐positive bacteria is less clear. Bacillus anthracis, the causative agent of anthrax, uniquely expresses three distinct Hfq proteins, two from the chromosome (Hfq1, Hfq2) and one from its pXO1 virulence plasmid (Hfq3). The protein sequences of Hfq1 and 3 are evolutionarily distinct from those of Hfq2 and of Hfqs found in other Bacilli. Here, the quaternary structure of each B. anthracis Hfq protein, as produced heterologously in Escherichia coli, was characterized. While Hfq2 adopts the expected hexamer structure, Hfq1 does not form similarly stable hexamers in vitro. The impact on the monomer–hexamer equilibrium of varying Hfq C‐terminal tail length and other sequence differences among the Hfqs was examined, and a sequence region of the Hfq proteins that was involved in hexamer formation was identified. It was found that, in addition to the distinct higher‐order structures of the Hfq homologs, they give rise to different phenotypes. Hfq1 has a disruptive effect on the function of E. coli Hfq in vivo, while Hfq3 expression at high levels is toxic to E. coli but also partially complements Hfq function in E. coli. These results set the stage for future studies of the roles of these proteins in B. anthracis physiology and for the identification of sequence determinants of phenotypic complementation.
Comparison of predicted pesticide concentrations in groundwater from SCI‐GROW and PRZM‐GW models with historical monitoring data
Authors: Estes Tammara L , Pai Naresh , Winchell Michael F
Published: August 2015

BACKGROUND

A key factor in the human health risk assessment process for the registration of pesticides by the US Environmental Protection Agency (EPA) is an estimate of pesticide concentrations in groundwater used for drinking water. From 1997 to 2011, these estimates were obtained from the EPA empirical model SCI‐GROW. Since 2012, these estimates have been obtained from the EPA deterministic model PRZM‐GW, which has resulted in a significant increase in estimated groundwater concentrations for many pesticides.

RESULTS

Historical groundwater monitoring data from the National Ambient Water Quality Assessment (NAWQA) Program (1991–2014) were compared with predicted groundwater concentrations from both SCI‐GROW (v.2.3) and PRZM‐GW (v.1.07) for 66 different pesticides of varying environmental fate properties. The pesticide environmental fate parameters associated with over‐ and underprediction of groundwater concentrations by the two models were evaluated.

CONCLUSION

In general, SCI‐GROW2.3 predicted groundwater concentrations were close to maximum historically observed groundwater concentrations. However, for pesticides with soil organic carbon content values below 1000 L kg−1 and no simulated hydrolysis, PRZM‐GW overpredicted, often by greater than 100 ppb. © 2015 Society of Chemical Industry