bluuebunny/crossref_metadata_2025 huggingface dataset:
Gamma radiation aging of EVA/EPDM blends: Effect of vinyl acetate (VA) content and radiation dose on the alteration in mechanical, thermal, and morphological behavior
Authors: Sharma Bhuwanesh Kumar , Krishnanand Kumar , Mahanwar P.A. , Sarma K.S.S. , Ray Chowdhury Subhendu
Published: January 2018

A series of ethylene vinyl acetate (EVA)/ethylene‐propylene diene elastomer (EPDM) blends (50/50 ratio) with four types of EVAs were prepared using brabender type batch mixer followed by compression molding. All compression‐molded samples were exposed to gamma radiation at 500, 1000, and 1500 kGy doses and were subjected to mechanical, compression set, thermal and morphological test. The % retention in tensile strength, elongation, and hardness were found higher for higher vinyl acetate (VA) containing radiation aged EVA/EPDM blends. The compression set value was decreased with increase of VA content. The thermal degradation kinetics of high VA containing irradiated blend (EVA40/EPDM) (EVA40 is 40%VA containing EVA) was found slower than those of lower VA containing blend (EVA18/EPDM). The surface morphology for EVA18/EPDM sample was transformed into more irregular one with more cracks and fragmented segments by aging at 1500 kGy dose while surface for EVA40/EPDM sample was found comparatively smooth, fine, and continuous with very few cracks and fragmented parts at similar dose. Thus, from the measured properties and morphology, it was revealed that the degree of degradation of blends kept on decreasing with increase in VA content. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46216.
Preparation of dummy template‐imprinted polymers for the rapid extraction of nonsteroidal anti‐inflammatory drugs residues in aquatic environmental samples
Authors: Guo Ping , Zhang Jingjing , Chen Xiaohui , Zhao Longshan
Published: January 2018

A molecularly imprinted polymer was synthesized and applied as a sorbent in the solid‐phase extraction device. The imprinted polymer was characterized by fourier‐transform infrared spectroscopy and scanning electron microscope. The results revealed that imprinted polymer possess sensitive selectivity and reliable adsorption properties for five NSAIDs. The imprinted polymer was successfully applied to the pre‐concentration for five NSAIDs in different water samples prior to UPLC‐MS/MS. In the early studies, several factors were investigated, including pH adjustment, the kind of elution solvent and the volume of elution solvent. Finally, we found that the pH 5 and an aliquot of 2 mL methanol were suitable for the water samples. The limits of detection and limits of quantitation of five nonsteroidal anti‐inflammatory drugs varied from 0.007 to 0.480 μg L−1 and 0.03 to 1.58 μg L−1, respectively. The spiking recoveries of the target analytes were 50.33‐127.64% at the levels of 0.2 μg L−1, 2 μg L−1 and 5 μg L−1. The precision and accuracy of this method showed a great increase compared with traditional solid‐phase extraction. The developed method was successfully applied to extraction and analysis of NSAIDs in different water samples with satisfactory results which could help us better understand their environmental fate and risk to ecological health.
Experimental Observation of Thermally Excited Triplet States of Heavier Group 15 Element Centered Diradical Dianions
Authors: Fang Yong , Zhang Li , Cheng Cheng , Zhao Yue , Abe Manabu , Tan Gengwen , Wang Xinping
Published: January 2018

One‐electron reductions of Mes*As=Fl* (1; Fl*=2,7‐di‐tert‐butylfluorenylidene, Mes*=2,4,6‐tBu3C6H2) and diarsaalkenes [1,2‐b]‐IF(=AsMes*)2 (2; IF=indenofluorene) with potassium led to the isolation of the arsenic‐centered radical anion salts 1K and 2K, respectively. The diradical dianion salts 2K2 and 3K2 were afforded by the reduction of 2 and 2,8‐tBu2‐[2,1‐b]‐IF(=AsMes*)2 (3) with an excess amount of KC8. The radicals have been investigated by single‐crystal X‐ray crystallography, EPR, and UV/Vis absorption spectroscopy, along with theoretical calculations. The calculations revealed that 2K2 and 3K2 feature open‐shell singlet ground states with singlet‐triplet energy gaps of 2.1 and 1.0 kcal mol−1, respectively. They are readily thermally excited to triplet states as demonstrated by EPR spectroscopy. The obtained diradicals represent the first examples of heavier Group 15 element centered diradicals with experimentally observable triplet states.
Carbon Molecular Sieve Membranes Derived from Tröger's Base‐Based Microporous Polyimide for Gas Separation
Authors: Wang Zhenggong , Ren Huiting , Zhang Shenxiang , Zhang Feng , Jin Jian
Published: January 2018

Carbon molecular sieve (CMS)‐based membranes have attracted great attention because of their outstanding gas‐separation performance. The polymer precursor is a key point for the preparation of high‐performance CMS membranes. In this work, a microporous polyimide precursor containing a Tröger's base unit was used for the first time to prepare CMS membranes. By optimizing the pyrolysis procedure and the soaking temperature, three TB–CMS membranes were obtained. Gas‐permeation tests revealed that the comprehensive gas‐separation performance of the TB–CMS membranes was greatly enhanced relative to that of most state‐of‐the‐art CMS membranes derived from polyimides reported so far.
Pregnancy greatly affects the steroidal module of the Athlete Biological Passport
Authors: Mullen Jenny , Gadot Yifat , Eklund Emma , Andersson Alexander , J. Schulze Jenny , Ericsson Magnus , Lindén Hirschberg Angelica , Rane Anders , Ekström Lena
Published: January 2018

Concentrations of urinary steroids are measured in anti‐doping test programs to detect doping with endogenous steroids. These concentrations are combined into ratios and followed over time in the steroidal module of the Athlete Biological Passport (ABP). The most important ratio in the ABP is the testosterone/epitestosterone (T/E) ratio but this ratio is subject to intra‐individual variations, especially large in women, which complicates interpretation. In addition, there are other factors affecting T/E. Pregnancy, for example, is known to affect the urinary excretion rate of epitestosterone and hence the T/E ratio. However, the extent of this variation and how pregnancy affect other ratios has not been fully evaluated. Here we have studied the urinary steroid profile, including 19‐norandrosterone (19‐NA), in 67 pregnant women and compared to postpartum. Epitestosterone was higher and, consequently, the T/E and 5αAdiol/E ratios were lower in the pregnant women. Androsterone/etiocholanolone (A/Etio) and 5αAdiol/5βAdiol, on the other hand, were higher in the first trimester as compared to postpartum (p<0.0001 and p=0.0396, respectively). There was no difference in A/T during pregnancy or after. 19‐NA was present in 90.5% of the urine samples collected from pregnant women. In this study, we have shown that the steroid profile of the ABP is affected by pregnancy, and hence can cause atypical passport findings. These atypical findings would lead to unnecessary confirmation procedures, if the patterns of pregnancy are not recognized by the ABP management units.
Activity and resource selection of a threatened carnivore: the case of black bears in northwestern Mexico
Authors: Lara‐Díaz Nalleli E. , Coronel‐Arellano Helí , López‐González Carlos A. , Sánchez‐Rojas Gerardo , Martínez‐Gómez Juan Esteban
Published: January 2018

Management and conservation strategies for endangered species require information on their temporal and spatial behavioral and habitat use relationships. We evaluated activity patterns and resource selection of black bears in northwestern Mexico. We surveyed 29 localities with 1450 camera traps stations from 2009 to 2013 in the states of Sonora and Chihuahua, Mexico. In each locality, we calculated the proportion of diurnal, nocturnal, and crepuscular activity through a kernel density estimator based on the time of independent photographic events, and we built a beta regression between diurnal density and annual temperature, seasonal rainfall (SR), human density, road density, daylight hours, season, and management type. To evaluate resource selection, we built a binomial logistic regression model incorporating Normalized Difference Vegetation Index (NDVI), mean and coefficient of variation of annual temperature, human population density (PD), terrain roughness, and season. Black bear activity was primarily diurnal with a bimodal tendency around sunrise and sunset. Diurnal activity (between sunrise and sunset) was positively influenced by daylight hours, SR, and private reserves and negatively influenced by anthropogenic factors. Resource selection was positively influenced by the coefficient of variation in temperature and NDVI and negatively associated with average annual temperature, PD, and terrain roughness. Activity patterns and resource use were similar to other regions in North America. However, temperature was one of the main factors influencing black bear activity and resource selection in our study areas and should be considered when developing management plans given projected increases in temperature expected under climate change scenarios. We present the first work of its kind for northwestern Mexico and considered it as an important component in future survey and management protocols for the species in the southern portion of its distribution.
Biomass for water defluoridation and current understanding on biosorption mechanisms: A review
Authors: Manna Suvendu , Roy Debasis , Adhikari Basudam , Thomas Sabu , Das Papita
Published: January 2018

Excessive fluoride (above 1.5 mg/L) containing water consumption for prolonged periods could pose health hazards, for example, dental fluorosis. Longer exposure could also cause skeletal fluorosis leading to the permanent deformity to skeleton. In the current context, use of biomasses for defluoridation would be a most economic and sustainable option for water defluoridation over the available alternatives. This article presents a brief summary of processes used biomasses for fluoride removal from aqueous solutions. This article also discusses the theoretical and instrumental approaches used by the researchers till date to understand the defluoridation mechanisms. The literature survey pointed that theoretical models such as Langmuir and Freundlich isotherms, pseudo‐first‐order and second‐order kinetic models, and different thermodynamic equations were also used to define the defluoridation by biomasses. Apart from the theoretical modeling, several researchers have also tried to understand the biomass‐based defluoridation by applying advanced instruments, for example, FTIR, XPS, NMR, TG, FESEM, and Raman spectroscopic analysis. © 2018 American Institute of Chemical Engineers Environ Prog, 37: 1560–1572, 2018
Progestin‐only and combined oral contraceptives and receptor‐defined premenopausal breast cancer risk: The Norwegian Women and Cancer Study
Authors: Busund Marit , Bugge Nora S. , Braaten Tonje , Waaseth Marit , Rylander Charlotta , Lund Eiliv
Published: January 2018

Receptor‐defined subtypes of breast cancer represent distinct cancer types and have differences in risk factors. Whether the two main hormonal forms of oral contraceptives (OCs); i.e. progestin‐only (POC) and combined oral contraceptives (COC), are differentially associated with these subtypes are not well known. The aim of our study was to assess the effect of POC and COC use on hormone receptor‐defined breast cancer risk in premenopausal women in a prospective population‐based cohort – The Norwegian Women and Cancer Study (NOWAC). Information on OC use was collected from 74,862 premenopausal women at baseline. Updated information was applied when follow‐up information became available. Multiple imputation was performed to handle missing data, and multivariable Cox regression models were used to calculate hazard ratios (HR) for breast cancer. 1,245 incident invasive breast cancer cases occurred. POC use ≥5 years was associated with ER+ (HR = 1.59, 95% CI 1.09– 2.32, ptrend = 0.03) and ER+/PR+ cancer (HR = 1.63, 95% CI 1.07–2.48, ptrend = 0.05), and was not associated with ER− (pheterogeneity = 0.36) or ER−/PR− (pheterogeneity = 0.49) cancer. COC use was associated with ER− and ER−/PR− cancer, but did not increase risk of ER+ and ER+/PR+ cancer. Current COC use gave different estimates for ER/PR‐defined subtypes (pheterogeneity = 0.04). This is the first study to show significant associations between POC use and hormone receptor‐positive breast cancer. The lack of power to distinguish effects of POC use on subtype development calls for the need of larger studies to confirm our finding.
CYR61/CCN1 Regulates Sclerostin Levels and Bone Maintenance
Authors: Zhao Gexin , Huang Bau-Lin , Rigueur Diana , Wang Weiguang , Bhoot Chimay , Charles Kemberly R , Baek Jongseung , Mohan Subburaman , Jiang Jie , Lyons Karen M
Published: January 2018

CYR61/CCN1 is a matricellular protein that resides in the extracellular matrix, but serves regulatory rather than structural roles. CYR61/CCN1 is found in mineralized tissues and has been shown to influence bone healing in vivo and osteogenic differentiation in vitro. In this study we generated Cyr61 bone-specific knockout mice to examine the physiological role of CYR61/CCN1 in bone development and maintenance in vivo. Extensive analysis of Cyr61 conditional knockout mice showed a significant decrease in both trabecular and cortical bone mass as compared to WT littermates. Our data suggest that CYR61/CCN1 exerts its effects on mature osteoblast/osteocyte function to modulate bone mass. Specifically, changes were observed in osteocyte/osteoblast expression of RankL, VegfA, and Sost. The increase in RankL expression was correlated with a significant increase in osteoclast number; decreased VegfA expression was correlated with a significant decrease in bone vasculature; increased Sost expression was associated with decreased Wnt signaling, as revealed by decreased Axin2 expression and increased adiposity in the bone marrow. Although the decreased number of vascular elements in bone likely contributes to the low bone mass phenotype in Cyr61 conditional knockout mice, this cannot explain the observed increase in osteoclasts and the decrease in Wnt signaling. We conducted in vitro assays using UMR-106 osteosarcoma cells to explore the role CYR61/CCN1 plays in modulating Sost mRNA and protein expression in osteocytes and osteoblasts. Overexpression of CYR61/CCN1 can suppress Sost expression in both control and Cyr61 knockout cells, and blocking Sost with siRNA can rescue Wnt responsiveness in Cyr61 knockout cells in vitro. Overall, our data suggest that CYR61/CCN1 modulates mature osteoblast and osteocyte function to regulate bone mass through angiogenic effects as well as by modulating Wnt signaling, at least in part through the Wnt antagonist Sost. © 2018 American Society for Bone and Mineral Research.
Association between pre‐sarcopenia, sarcopenia, and bone mineral density in patients with chronic hepatitis C
Authors: Bering Tatiana , Diniz Kiara G.D. , Coelho Marta Paula P. , Vieira Diego A. , Soares Maria Marta S. , Kakehasi Adriana M. , Correia Maria Isabel T.D. , Teixeira Rosângela , Queiroz Dulciene M.M. , Rocha Gifone A. , Silva Luciana D.
Published: January 2018

Background

Preserved skeletal muscle is essential for the maintenance of healthy bone. Loss of bone mineral density (BMD) and muscle strength, considered a predictor of BMD, have been demonstrated in patients with cirrhosis, but they are poorly studied in chronic hepatitis C (CHC) without cirrhosis. Thus, we aimed to evaluate the prevalence of low BMD and its association with body composition, muscle strength, and nutritional status in CHC.

Methods

One hundred and four subjects [mean age, 50.5 ± 11.3 years; 75.0% males; 67.3% non‐cirrhotic; and 32.7% with compensated cirrhosis] with CHC, prospectively, underwent scanning of the lean tissue, appendicular skeletal muscle mass (ASM), fat mass, lumbar spine, hip, femoral neck, and whole‐body BMD by dual‐energy X‐ray absorptiometry. Muscle strength was assessed by dynamometry. Sarcopenia was defined by the presence of both low, ASM/height2 (ASMI) and low muscle strength according to the European Working Group on Sarcopenia in Older People criteria. The cut‐off points for low ASMI and low muscle strength, for women and men, were < 5.45 and < 7.26 kg/m2 and < 20 and < 30 kg, respectively. According to the adopted World Health Organization criteria in men aged > 50 years, the T‐score of osteopenia is between −1.0 and −2.49 standard deviation (SD) below the young average value and of osteoporosis is ≥−2.5 SD below the young normal mean for men, and the Z‐score of low bone mass is ≤−2.0 SD below the expected range in men aged < 50 years and women in the menacme. Nutritional status evaluation was based on the Controlling Nutritional Status score.

Results

Low BMD, low muscle strength, pre‐sarcopenia, sarcopenia, and sarcopenic obesity were observed in 34.6% (36/104), 27.9% (29/104), 14.4% (15/104), 8.7% (9/104), and 3.8% (4/104) of the patients, respectively. ASMI was an independent predictor of BMD (P < 0.001). Sarcopenia was independently associated with bone mineral content (P = 0.02) and malnutrition (P = 0.01). In 88.9% of the sarcopenic patients and in all with sarcopenic obesity, BMI was normal. The mid‐arm muscle circumference was positively correlated with ASMI (r = 0.88; P < 0.001).

Conclusions

This is the first study to demonstrate that ASM is an independent predictor of BMD in CHC. Mid‐arm muscle circumference coupled with handgrip strength testing should be incorporated into routine clinical practice to detect low muscle mass, which may be underdiagnosed when only BMI is used. These findings may influence clinical decision‐making and contribute to the development of effective strategies to screen the musculoskeletal abnormalities in CHC patients, independently of the stage of the liver disease.
Ecophysiology of the internal cycling of nitrogen for tree growth
Authors: Millard Peter
Published: January 2018

Internal cycling of nitrogen has been shown to be a major source of nitrogen used for the seasonal growth of both evergreen and deciduous trees providing up to 90% of N used for leaf growth of some species. The processes of internal cycling comprise seasonal nitrogen storage, followed by remobilisation during either periods of growth (e.g. in the spring) or during leaf senescence. The ecophysiology of these processes is reviewed, along with the methods used to quantify their contribution to tree growth.

Nitrogen budget studies have been widely used to estimate internal cycling, particularly in relation to soil fertility. These studies have shown that as trees develop their rate of N uptake decreases, but as they grow their storage capacity increases, However, budget studies are imprecise and have not always quantified remobilisation adequately. An alternative approach has been the use of 15N to quantify N uptake and partitioning, allowing precise measurements of N storage and remobilisation to be made. The use of isotopes has allowed experiments to be run which have shown that environmental factors such as soil fertility influence the amount of N stored, but have no direct influence upon the amount of N remobilised. These methods are discussed in light of recent research on N remobilisation, which has provided an understanding of the processes of storage and remobilisation which potentially allows direct measurements to be made in field grown trees for the first time.
Genesis and dynamics of an oxic dystrochrept and a typic haploperox from ultrabasic rock in the tropical rain forest climate of south‐east Brazil
Authors: Pfisterer Ulrich , Blume Hans‐Peter , Kanig Martin
Published: January 2018

Oxisols are a product of long and intense weathering. Their actual characteristics can neither be traced back to a certain climatic period, nor do they reveal the present soil‐forming factors. In this paper, therefore, a reconstruction of the soil genesis of a strongly weathered Oxisol is attempted by comparing the present mineralogical status and the recent dynamics of selected elements with a nearby Inceptisol from the same catena. The parent rock of both soils is serpentinized dunite with nepheline‐syenitic veins; the soil moisture regime is udic. Chemical and mineralogical parameters, as well as the concentration of elements in the soil solution of a Typic Haploperox and an Oxic Dystrochrept from the same catena were analyzed for one year. The dynamics of Si and Mg strongly depended on the state of weathering. In the saprolite of the Dystrochrept, Si is partially removed and partially fixed by the formation of quartz and mixed layer minerals. Mg is first fixed in mixed layer minerals, but is during consecutive weathering leached from the transition zone from saprolite to the oxic horizon. Due to the high redox potential, Fe is not soluble, forming goethite in the upper part of the saprolite. Al is also not removed and is finally fixed in kaolinite. In the weathered upper part of both profiles the concentration of Al, Si, Mg and Fe in the soil solution is too low to perceive a further weathering.

The present dynamics of Fe, Al, Mg and Si and the mineralogical status of the Dystrochrept indicate that these processes are similar to those that have led to the formation of the Haploperox. The soils, therefore, developed exclusively by the relative enrichment of Al and Fe, the partial loss of Si and the almost complete loss of Mg. Desilification and ‘laterisation’ are hence processes occurring also presently under a tropical rain forest climate.
Are they all “serendipitous”?
Authors: Morita Takeyuki , Johnston Charles Samuel
Published: January 2018

McKercher's cultural tourist typology (2002) has been used widely for destinations. This research began as a replication of McKercher; the current paper reports new insights. The aims are to examine the typology at New Zealand's Bay of Islands and modify it accordingly. Our modification provides improved understanding of the Serendipitous tourist. The relatively large number of Serendipitous tourists visiting the Bay of Islands suggested that they could be broken into 2 different groups, expanding McKercher's original 5 typologies into a conventional 2‐by‐3 matrix. “Serendipitous” remains a useful label for one group, and “Ancillary” was chosen for the newly identified subtype. Differences between them are explained.
Heparin but not tissue plasminogen activator improves outcomes in donation after circulatory death liver transplantation in a porcine model
Authors: Hessheimer Amelia J. , Vendrell Marina , Muñoz Javier , Ruíz Ángel , Díaz Alba , Sigüenza Luís Flores , Lanzilotta Jorge Rodríguez , Delgado Oliver Eduardo , Fuster Jose , Navasa Miquel , García‐Valdecasas Juan Carlos , Taurá Pilar , Fondevila Constantino
Published: January 2018

Ischemic‐type biliary lesions (ITBLs) arise most frequently after donation after circulatory death (DCD) liver transplantation and result in high morbidity and graft loss. Many DCD grafts are discarded out of fear for this complication. In theory, microvascular thrombi deposited during donor warm ischemia might be implicated in ITBL pathogenesis. Herein, we aim to evaluate the effects of the administration of either heparin or the fibrinolytic drug tissue plasminogen activator (TPA) as means to improve DCD liver graft quality and potentially avoid ITBL. Donor pigs were subjected to 1 hour of cardiac arrest (CA) and divided among 3 groups: no pre‐arrest heparinization nor TPA during postmortem regional perfusion; no pre‐arrest heparinization but TPA given during regional perfusion; and pre‐arrest heparinization but no TPA during regional perfusion. In liver tissue sampled 1 hour after CA, fibrin deposition was not detected, even when heparin was not given prior to arrest. Although it was not useful to prevent microvascular clot formation, pre‐arrest heparin did offer cytoprotective effects during CA and beyond, reflected in improved flows during regional perfusion and better biochemical, functional, and histological parameters during posttransplantation follow‐up. In conclusion, this study demonstrates the lack of impact of TPA use in porcine DCD liver transplantation and adds to the controversy over whether the use of TPA in human DCD liver transplantation really offers any protective effect. On the other hand, when it is administered prior to CA, heparin does offer anti‐inflammatory and other cytoprotective effects that help improve DCD liver graft quality. Liver Transplantation 24 665–676 2018 AASLD.
On the solutions of the equation AXB = C under Toeplitz‐like and Hankel matrices constraint
Authors: Yang Juan , Deng Yuan‐bei
Published: January 2018

In this paper, we are mainly concerned with 2 types of constrained matrix equation problems of the form AXB=C, the least squares problem and the optimal approximation problem, and we consider several constraint matrices, such as general Toeplitz matrices, upper triangular Toeplitz matrices, lower triangular Toeplitz matrices, symmetric Toeplitz matrices, and Hankel matrices. In the first problem, owing to the special structure of the constraint matrix
, we construct special algorithms; necessary and sufficient conditions are obtained about the existence and uniqueness for the solutions. In the second problem, we use von Neumann alternating projection algorithm to obtain the solutions of problem. Then we give 2 numerical examples to demonstrate the effectiveness of the algorithms.
Population-Specific Migration Patterns of Wild Adult Summer-Run Chinook Salmon Passing Wells Dam, Washington
Authors: Mann Ryan D. , Snow Charles G.
Published: January 2018

Summer-run Chinook Salmon Oncorhynchus tshawytscha migrating over Wells Dam, Washington, enter a habitat characterized by blocked upstream access, high tributary water temperature regimes, and robust tribal and recreational fisheries. In 2011, we initiated a 2-year radiotelemetry study to identify population-specific run timing, movement, and mortality of naturally produced fish passing the dam. Five hundred seventeen salmon were radio-tagged at Wells Dam over 2 years of study. The highest proportion (44%) of tagged fish escaped to the Okanogan River, but spawning populations from the Methow River (16%), Wenatchee River (6%), Entiat River (5%), and the Columbia River upstream (14%) and downstream of Wells Dam (14%) were also represented. In general, tributary-spawning fish had significantly earlier run timing than did main-stem–spawning fish. We observed very little movement among spawning tributaries, but a significant proportion of fish (~30%) were detected holding in the tailrace of Chief Joseph Dam on the Columbia River prior to spawning, including fish from populations many kilometers downstream of Wells Dam. Fallback was common in each year of the study, and we calculated that passage at Wells Dam was overestimated by 27.5% in 2011 and 32.0% in 2012 due to fallback and re-ascension. Of the fish that remained upstream, 16% in 2011 and 22% in 2012 were estimated to have died prior to spawning, excluding fish that were known or suspected to have been harvested. In 2012, warm water temperatures (>20°C) in the Okanogan River resulted in a thermal barrier that delayed migration but did not affect spawning distribution within the river compared with 2011, when no significant thermal barrier was detected. Our results highlight some of the complex migration and distribution patterns of natural-origin Chinook Salmon passing Wells Dam and should assist managers in upstream population and fishery modeling efforts.
Evaluation of Unbaited Hoop Nets for Simultaneously Assessing Channel Catfish and Flathead Catfish populations in the Minnesota River
Authors: Sindt Anthony R.
Published: January 2018

Fisheries managers desire efficient sampling methods with sufficient precision for monitoring ictalurid catfish populations. For this study, I conducted single unbaited hoop-net surveys in the Minnesota River to evaluate the efficacy of simultaneously assessing stock-size (≥280-mm) Channel Catfish Ictalurus punctatus and quality-size (≥510-mm) Flathead Catfish Pylodictis olivaris populations. I compared catch rates and length-frequency distributions among months (April–September) and used resampling procedures to estimate the number of hoop-net samples needed to achieve desirable precision of catch rate estimates and adequate statistical power. Catch rates (mean ± SE) were 2.1 ± 0.3 fish/net-night for Channel Catfish and 0.8 ± 0.1 fish/net-night for Flathead Catfish. Resampling procedures demonstrated that desirable precision (i.e., relative SE ≤ 25) and adequate statistical power (≥0.80 with α = 0.10) to detect 50% reductions in mean catch rates with two-tailed t-tests could be achieved for both species with as few as 68 hoop-net samples during August. Unbaited hoop nets are effective for simultaneously assessing Channel Catfish and Flathead Catfish populations in the Minnesota River, and conducting surveys during August provides the best balance between catch rate and precision while minimizing perceived environmental and behavioral biases. However, the amount of sampling effort needed to detect small population changes (<50%) and to collect sufficient sample sizes for age and growth analyses may be logistically prohibitive. This study emphasizes the importance of evaluating precision and statistical power of sampling methods so that fisheries managers can identify the most suitable methods for their specific objectives.
Mixed and least‐squares finite element methods with application to linear hyperbolic problems
Authors: Kalchev Delyan Z. , Manteuffel Thomas A. , Münzenmaier Steffen
Published: January 2018

In this paper, a few dual least‐squares finite element methods and their application to scalar linear hyperbolic problems are studied. The purpose is to obtain L2‐norm approximations on finite element spaces of the exact solutions to hyperbolic partial differential equations of interest. This is approached by approximating the generally infeasible quadratic minimization that defines the L2‐orthogonal projection of the exact solution, by feasible least‐squares principles using the ideas of the original
method proposed in the context of elliptic equations. All methods in this paper are founded upon and extend the
approach that is rather general and applicable beyond the setting of elliptic problems. Error bounds are shown that point to the factors affecting the convergence and provide conditions that guarantee optimal rates. Furthermore, the preconditioning of the resulting linear systems is discussed. Numerical results are provided to illustrate the behavior of the methods on common finite element spaces.
On optimal singular control problem for general Mckean‐Vlasov differential equations: Necessary and sufficient optimality conditions
Authors: Hafayed Mokhtar , Meherrem Shahlar , Eren Şaban , Guçoglu Deniz Hasan
Published: January 2018

In this paper, we derive the necessary and sufficient conditions for optimal singular control for systems governed by general controlled McKean‐Vlasov differential equations, in which the coefficients depend on the state of the solution process as well as of its law and control. The control domain is assumed to be convex. The control variable has 2 components, ie, the first being absolutely continuous and the second being singular. The proof of our result is based on the derivative of the solution process with respect to the probability law and a corresponding Itô formula. Finally, an example is given to illustrate the theoretical results.
Calculus of variations approach for state and parameter estimation in switched 1D hyperbolic PDEs
Authors: Nguyen Van Tri , Georges Didier , Besançon Gildas
Published: January 2018

This paper proposes the use of calculus of variations to solve the problem of state and parameter estimation for a class of switched 1‐dimensional hyperbolic partial differential equations coupled with an ordinary differential equation. The term “switched” here refers to a system changing its characteristics according to a switching rule, which may depend on time, parameters of the system, and/or state of the system. The estimation method is based on a smooth approximation of the system dynamics and the use of variational calculus on an augmented Lagrangian cost functional to get the sensitivity with respect to the initial state and some (possibly distributed) parameters of the system. Those sensitivities or variations, together with related adjoint systems, are used as inputs for an optimization algorithm to identify the values of the variables to be estimated. Two examples are provided to demonstrate the effectiveness of the proposed method. The first one is concerned with a switched overland flow model, developed from Saint‐Venant equations and Green‐Ampt law; the second example deals with a switched free traffic flow model based on the Lighthill‐Whitham‐Richards representation, modified by the presence of a relief route.
Clinical and genetic associations for carboplatin‐related ototoxicity in children treated for retinoblastoma: A retrospective noncomparative single‐institute experience
Authors: Soliman Sameh E. , D'Silva Crystal N. , Dimaras Helen , Dzneladze Irakli , Chan Helen , Gallie Brenda L.
Published: January 2018

Background

Children with retinoblastoma treated with carboplatin chemotherapy risk moderate to severe, irreversible hearing loss. Based on published evidence, we hypothesized that ototoxicity risk is associated with clinical parameters and variants in candidate genes in drug metabolism pathways (methyltransferases [thiopurine S‐methyltransferase, TPMT] and [catechol‐O‐methyltransferase, COMT], and drug transporter ABCC3).

Procedure

We retrospectively reviewed clinical records of patients with retinoblastoma treated with carboplatin chemotherapy regarding age (at diagnosis and chemotherapy initiation), chemotherapy sessions (cycles number, drug doses, and cumulative carboplatin dose), and hearing loss (defined as ototoxicity ≥grade 2 by at least one classification system). Blood samples were genotyped for genetic variants in TPMT (rs12201199, rs1800460), COMT (rs4646316, rs9332377), and ABCC3 (rs1051640) by quantitative PCR and confirmed by allele‐specific PCR. Univariate statistical tests, receiver‐operating characteristic analysis, and Kaplan–Meier curves were used to examine the association between hearing loss, clinical factors, and variants in candidate genes.

Results

Audiometric data and stored DNA were available for 71 patients with retinoblastoma (88% carried an RB1 pathogenic variant allele). Median carboplatin cumulative dose was 1,400 mg/m2 (260–5,148 mg/m2). Ototoxicity occurred in 18 patients (25%), strongly associated with age at diagnosis (P = 0.01) and age at chemotherapy initiation (OR = 4.99, P = 0.008). The highest likelihood ratio of hearing loss was associated with chemotherapy initiation <4.25 months of age. Ototoxicity was not associated with any tested genetic variants.

Conclusions

We observed a 25% prevalence of ototoxicity in patients with retinoblastoma treated with carboplatin, higher than previously published. Age at chemotherapy initiation was associated with carboplatin‐induced ototoxicity, with children <4.25 months of age at highest risk.
Bleeding and thrombotic complications of pediatric liver transplant
Authors: Borst Alexandra J. , Sudan Debra L. , Wang Laura A. , Neuss Michael J. , Rothman Jennifer A. , Ortel Thomas L.
Published: January 2018

Background

Pediatric patients undergoing liver transplant are at significant risk for bleeding and thrombotic complications due to the complex nature of rebalanced hemostasis in patients with liver disease.

Methods/objectives

We reviewed records of 92 pediatric liver and multivisceral transplant cases at Duke University Medical Center between January 2009 and December 2015. The goal was to define the nature and incidence of bleeding and thrombotic complications in this cohort and define potential risk factors.

Results

There were 24 major bleeding events in 19 transplants (incidence 20.7%) and 30 thrombotic events in 23 transplants (incidence 25%). Five of the 10 retransplantations were for vascular thrombotic complications. Thirty‐day mortality was 4.9%, and three of these four deaths were due to vascular thrombosis. No bleeding events led to retransplantation or mortality. Prophylactic aspirin was associated with decreased risk of thrombosis without increased bleeding. Prophylactic heparin did not increase bleeding risk. Laboratory assays predicted events poorly, apparently failing to capture the nuanced and dynamic interplay between pro‐ and anticoagulant factors in the posttransplant patient.

Conclusions

Both bleeding and thrombosis are frequent in this population, but only thrombotic complications contributed to retransplantation and mortality. A standardized approach to coagulation testing and antithrombotic therapy may be useful in predicting and reducing adverse outcomes. Alternative approaches to monitoring hemostasis need to be prospectively investigated in this complex patient population.
Inflammatory response and treatment tolerance of long‐term infusion of the anti‐GD2 antibody ch14.18/CHO in combination with interleukin‐2 in patients with high‐risk neuroblastoma
Authors: Ceylan Kiraz , Jahns Luciana J. , Lode Bjoern N. , Ehlert Karoline , Kietz Silke , Troschke‐Meurer Sascha , Siebert Nikolai , Lode Holger N.
Published: January 2018

Background

The monoclonal anti‐GD2 antibody ch14.18/CHO in combination with IL‐2 is active and effective in high‐risk neuroblastoma (NB) patients. Here, we investigated the inflammatory response and treatment tolerance of long‐term infusion (LTI) of ch14.18/CHO (10 × 10 mg/m2; 24 hr) in combination with subcutaneous (s.c.) IL‐2 in a single center program.

Methods

Fifty‐three NB patients received up to six cycles of 100 mg/m2 ch14.18/CHO (d8–18, where d represents day(s)) as LTI combined with 6 × 106 IU/m2 s.c. IL‐2 (d1–5; 8–12) and 160 mg/m2 oral 13‐cis retinoic acid (RA) (d19–32). Side effects of ch14.18/CHO and IL‐2 treatment require hospitalization of patients on d8. Treatment tolerance was evaluated daily with clinical parameters (body temperature, vital signs, Lansky performance status, requirement of i.v. concomitant medication) to define an outpatient candidate status. sIL‐2‐R and C‐reactive protein values were determined to assess the inflammatory response.

Results

LTI of ch14.18/CHO (d8–18) in combination with s.c.IL‐2 (d8–12) showed an acceptable treatment tolerance that allowed all patients to receive part of the treatment as an outpatient (median time point of discharge: d15 for all cycles). The treatment tolerance improved from cycle to cycle and the time to become an outpatient candidate decreased from d15 to d13 in subsequent cycles. Clinical and laboratory parameters indicate a maximum inflammatory response at d11 of each cycle. Interestingly, the soluble IL‐2 receptor remained increased at baseline of the next cycle indicating immune activation over the entire treatment period of 6 months.

Conclusions

LTI of ch14.18/CHO combined with s.c.IL‐2 shows an improved tolerance in subsequent cycles allowing outpatient treatment.
Optimization of Aqueous Extraction from Kalanchoe pinnata Leaves to Obtain the Highest Content of an Anti‐inflammatory Flavonoid using a Response Surface Model
Authors: dos Santos Nascimento Luana Beatriz , de Aguiar Paula Fernandes , Leal‐Costa Marcos Vinicius , Coutinho Marcela Araújo Soares , Borsodi Maria Paula Gonçalves , Rossi‐Bergmann Bartira , Tavares Eliana Schwartz , Costa Sônia Soares
Published: January 2018

Introduction

The medicinal plant Kalanchoe pinnata is a phenolic‐rich species used worldwide. The reports on its pharmacological uses have increased by 70% in the last 10 years. The leaves of this plant are the main source of an unusual quercetin‐diglycosyl flavonoid (QAR, quercetin arabinopyranosyl rhamnopyranoside), which can be easily extracted using water. QAR possess a strong in vivo anti‐inflammatory activity.

Objective

To optimize the aqueous extraction of QAR from K. pinnata leaves using a three‐level full factorial design.

Material and methods

After a previous screening design, time (x1) and temperature (x2) were chosen as the two independent variables for optimization. Freeze‐dried leaves were extracted with water (20% w/v), at 30°C, 40°C or 50°C for 5, 18 or 30 min. QAR content (determined by HPLC‐DAD) and yield of extracts were analyzed. The optimized extracts were also evaluated for cytotoxicity.

Results

The optimal heating times for extract yield and QAR content were similar in two‐dimensional (2D) surface responses (between 12.8 and 30 min), but their optimal extraction temperatures were ranged between 40°C and 50°C for QAR content and 30°C and 38°C for extract yield. A compromise region for both parameters was at the mean points that were 40°C for the extraction temperature and 18 min for the total time.

Conclusion

The optimized process is faster and spends less energy than the previous one (water; 30 min at 55°C); therefore is greener and more attractive for industrial purposes. This is the first report of extraction optimization of this bioactive flavonoid. Copyright © 2018 John Wiley & Sons, Ltd.
Regulating hippocampal hyperexcitability through GABAB Receptors
Authors: Lang Min , Moradi‐Chameh Homeira , Zahid Tariq , Gane Jonathan , Wu Chiping , Valiante Taufik , Zhang Liang
Published: January 2018

Disturbances of GABAergic inhibition are a major cause of epileptic seizures. GABA exerts its actions via ionotropic GABAA receptors and metabotropic G protein‐coupled GABAB receptors. Malfunction of GABAA inhibition has long been recognized in seizure genesis but the role of GABAB receptors in controlling seizure activity is still not well understood. Here, we examined the anticonvulsive, or inhibitory effects, of GABAB receptors in a mouse model of hippocampal kindling as well as mouse hippocampal slices through the use of GS 39783, a positive allosteric GABAB receptor modulator, and CGP 55845, a selective GABAB receptor antagonist. When administered via intraperitoneal injections in kindled mice, GS 39783 (5 mg/kg) did not attenuate hippocampal EEG discharges, but did reduce aberrant hippocampal spikes, whereas CGP 55845 (10 mg/kg) prolonged hippocampal discharges and increased spike incidences. When examined in hippocampal slices, neither GS 39783 at 5 μmol/L nor the GABAB receptor agonist baclofen at 0.1 μmol/L alone significantly altered repetitive excitatory field potentials, but GS 39783 and baclofen together reversibly abolished these field potentials. In contrast, CGP 55845 at 1 μmol/L facilitated induction and incidence of these field potentials. In addition, CGP 55845 attenuated the paired pulse depression of CA3 population spikes and increased the frequency of EPSCs in individual CA3 pyramidal neurons. Collectively, these data suggest that GABABB receptors regulate hippocampal hyperexcitability by inhibiting CA3 glutamatergic synapses. We postulate that positive allosteric modulation of GABAB receptors may be effective in reducing seizure‐related hyperexcitability.
Small intestinal permeability in older adults
Authors: Valentini Luzia , Ramminger Sara , Haas Verena , Postrach Elisa , Werich Martina , Fischer André , Koller Michael , Swidsinski Alexander , Bereswill Stefan , Lochs Herbert , Schulzke Jörg‐Dieter
Published: January 2018

It is not yet clear whether intestinal mucosal permeability changes with advancing age in humans. This question is of high importance for drug and nutrition approaches for older adults. Our main objective was to answer the question if small intestinal barrier integrity deteriorates with healthy aging. We conducted a cross‐sectional study including the pooled data of 215 nonsmoking healthy adults (93 female/122 male), 84 of whom were aged between 60 and 82 years. After a 12‐h fast, all participants ingested 10 g of lactulose and 5 g of mannitol. Urine was collected for 5 h afterwards and analyzed for test sugars. The permeability index (PI = lactulose/mannitol) was used to assess small intestinal permeability. Low‐grade inflammation defined by high‐sensitivity C‐reactive protein ≥1 mL/L and kidney function (estimated glomerular filtration rate) were determined in the older age group. The PI was similar in older compared to younger adults (P = 0.887). However, the urinary recovery of lactulose and mannitol was lower in the older adults and this change was neither associated with urinary volume nor glomerular filtration rate. The PI was not significantly correlated with low‐grade inflammation or presence of noninsulin‐dependent type 2 diabetes. However, it significantly deteriorated in the copresence of both conditions compared to low‐grade inflammation alone (P = 0.043) or type 2 diabetes alone (P = 0.015). Small intestinal mucosal barrier does not deteriorate with age per se. But low‐grade inflammation coupled with minor disease challenges, such as type 2 diabetes, can compromise the small intestinal barrier.
Polyimides as cathodic materials in lithium batteries: Effect of the chemical structure of the diamine monomer
Authors: Hernández Guiomar , Salsamendi Maitane , Morozova Sofia M. , Lozinskaya Elena I. , Devaraj Shanmukaraj , Vygodskii Yakov S. , Shaplov Alexander S. , Mecerreyes David
Published: January 2018

Polyimides are being investigated as alternative, environmentally friendly and safe organic electrode materials for lithium and sodium batteries. However, further improvements need the proper chemical design of these polymers. In this paper, the effect of chemical structure of polyimides on their performance as cathodic materials in lithium batteries was investigated in detail. More in particular, we studied polyimides based on seven different diamine monomers in combination with best performing naphthalenic dianhydride monomer. The first set included the so‐called cardo diamines possessing additional redox‐active carbonyl group with the goal to enhance the theoretical capacity of the polymer. Second, several aromatic diamines including additional functionalities such as cyclic amides, anthrone, or quinolidinium groups were investigated. Finally, aliphatic diamines, containing oxyethylene moieties and thus capable to increase the ionic conductivity of the resulting polymer system, were explored. Among the different polyimides, the “cardo” one based on naphthalenic dianhydride and aromatic aniline phthalein with an additional carbonyl group showed the best results in terms of battery performance. Such polyimide was capable to deliver up to 130 mAhg−1 specific capacity (87% of the theoretical value) at 25 °C and at a current density of 250 mAg−1 during 100 charge/discharge cycles. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 714–723
Rejection of mismatched disturbances for systems with input delay via a predictive extended state observer
Authors: Sanz R. , Garcia P. , Fridman E. , Albertos P.
Published: January 2018

The problem of output stabilization and disturbance rejection for input‐delayed systems is tackled in this work. First, a suitable transformation is introduced to translate mismatched disturbances into an equivalent input disturbance. Then, an extended state observer is combined with a predictive observer structure to obtain a future estimation of both the state and the disturbance. A disturbance model is assumed to be known but attenuation of unmodeled components is also considered. The stabilization is proved via Lyapunov‐Krasovskii functionals, leading to sufficient conditions in terms of linear matrix inequalities for the closed‐loop analysis and parameter tuning. The proposed strategy is illustrated through a numerical example.