bluuebunny/crossref_metadata_2025 huggingface dataset:
The Quest for Value‐Added Products from Carbon Dioxide and Water in a Dielectric Barrier Discharge: A Chemical Kinetics Study
Authors: Snoeckx Ramses , Ozkan Alp , Reniers Francois , Bogaerts Annemie
Published: November 2016

Recycling of carbon dioxide by its conversion into value‐added products has gained significant interest owing to the role it can play for use in an anthropogenic carbon cycle. The combined conversion with H2O could even mimic the natural photosynthesis process. An interesting gas conversion technique currently being considered in the field of CO2 conversion is plasma technology. To investigate whether it is also promising for this combined conversion, we performed a series of experiments and developed a chemical kinetics plasma chemistry model for a deeper understanding of the process. The main products formed were the syngas components CO and H2, as well as O2 and H2O2, whereas methanol formation was only observed in the parts‐per‐billion to parts‐per‐million range. The syngas ratio, on the other hand, could easily be controlled by varying both the water content and/or energy input. On the basis of the model, which was validated with experimental results, a chemical kinetics analysis was performed, which allowed the construction and investigation of the different pathways leading to the observed experimental results and which helped to clarify these results. This approach allowed us to evaluate this technology on the basis of its underlying chemistry and to propose solutions on how to further improve the formation of value‐added products by using plasma technology.
Selective Production of Toluene from Biomass‐Derived Isoprene and Acrolein
Authors: Dai Tao , Li Changzhi , Zhang Bo , Guo Haiwei , Pan Xiaoli , Li Lin , Wang Aiqin , Zhang Tao
Published: November 2016

Toluene is a basic chemical that is currently produced from petroleum resources. In this paper, we report a new route for the effective synthesis of toluene from isoprene and acrolein, two reactants readily available from biomass, through a simple two‐step reaction. The process includes Diels–Alder cycloaddition of isoprene and acrolein in a Zn‐containing ionic liquid at room temperature to produce methylcyclohex‐3‐enecarbaldehydes (MCHCAs) as intermediates, followed by M (M=Pt, Pd, Rh)/Al2O3‐catalyzed consecutive dehydrogenation–decarbonylation of the MCHCAs at 573 K to generate toluene with an overall yield up to 90.7 %. Model reactions indicated that a synergistic inductive effect of the C=C double bond and the aldehyde group in MCHCA plays a key role in initiating the consecutive dehydrogenation–decarbonylation, and that methyl benzaldehydes are the key intermediates in the gas‐phase transformation of MCHCAs. Microcalorimetric adsorption of CO on different catalysts showed that decarbonylation of the substrate occurs more likely on the strong adsorption sites. To the best of our knowledge, it is the first report of Pt/Al2O3‐catalyzed consecutive dehydrogenation–decarbonylation of a given compound in one reactor. This work provides a highly efficient and environmental friendly route to toluene by utilizing two compounds that can be prepared from biomass.
Annual banned‐substance review: analytical approaches in human sports drug testing
Authors: Thevis Mario , Kuuranne Tiia , Geyer Hans , Schänzer Wilhelm
Published: November 2016

There has been an immense amount of visibility of doping issues on the international stage over the past 12 months with the complexity of doping controls reiterated on various occasions. Hence, analytical test methods continuously being updated, expanded, and improved to provide specific, sensitive, and comprehensive test results in line with the World Anti‐Doping Agency's (WADA) 2016 Prohibited List represent one of several critical cornerstones of doping controls. This enterprise necessitates expediting the (combined) exploitation of newly generated information on novel and/or superior target analytes for sports drug testing assays, drug elimination profiles, alternative test matrices, and recent advances in instrumental developments. This paper is a continuation of the series of annual banned‐substance reviews appraising the literature published between October 2015 and September 2016 concerning human sports drug testing in the context of WADA's 2016 Prohibited List. Copyright © 2016 John Wiley & Sons, Ltd.
Organic impurity profiling of methylone and intermediate compounds synthesized from catechol
Authors: Heather Erin , Bortz Adam , Shimmon Ronald , McDonagh Andrew M.
Published: November 2016

This work examined the synthesis and organic impurity profile of methylone prepared from catechol. The primary aim of this work was to determine whether the synthetic pathway used to prepare 3,4‐methylenedioxypropiophenone could be ascertained through analysis of the synthesized methylone. The secondary aim was the structural elucidation and origin determination of the organic impurities detected in methylone and the intermediate compounds. The organic impurities present in the reaction products were identified using GC–MS and NMR spectroscopy. Six organic impurities were detected in 1,3‐benzodioxole and identified as the 1,3‐benzodioxole dimer, 1,3‐benzodioxole trimer, [1,3] dioxolo[4,5‐b]oxanthrene, 4,4′‐, 4,5′‐, and 5,5′‐methylenebis‐1,3‐benzodioxole. Six organic impurities were detected in 3,4‐methylenedioxypropiophenone and identified as (2‐hydroxyphenyl) propanoate, [2‐(chloromethoxy) phenyl] propanoate, (2‐propanoyloxyphenyl)propanoate, 5‐[1‐(1,3‐benzodioxol‐5‐yl)prop‐1‐enyl]‐1,3‐benzodioxole, (5E)‐ and (5Z)‐7‐(1,3‐benzodioxol‐5‐yl)‐5‐ethylidene‐6‐methyl‐cyclopenta[f][1,3]benzodioxole). Exploratory synthetic experiments were also conducted to unambiguously identify the organic impurities detected in 3,4‐methylenedioxypropiophenone. Two organic impurities were detected in 5‐bromo‐3,4‐methylenedioxypropiophenone and identified as [2‐(chloromethoxy)phenyl] propanoate and 3,4‐methylenedioxypropiophenone. Five organic impurities were detected in methylone and identified as 3,4‐methylenedioxypropiophenone, 1‐(1,3‐benzodioxol‐5‐yl)‐N‐methyl‐propan‐1‐imine, 1‐(1,3‐benzodioxol‐5‐yl)‐2‐methylimino‐propan‐1‐one, 1‐(1,3‐benzodioxol‐5‐yl)‐N1,N2‐dimethyl‐propane‐1,2‐diimine and butylated hydroxytoluene. The origin of these organic impurities was also ascertained, providing valuable insight into the chemical profiles of methylone and the intermediate compounds. However, neither the catechol precursor nor the 1,3‐benzodioxole intermediate could be identified based on the organic impurities detected in the synthesized methylone using standard techniques. This demonstrated that the organic impurity profiling of methylone had limitations in the determination of precursor chemical and synthetic pathways used. Copyright © 2017 John Wiley & Sons, Ltd.
Bridge under troubled water: Turbulence and niche partitioning in fish foraging
Authors: Pekcan‐Hekim Zeynep , Hellén Noora , Härkönen Laura , Nilsson Per Anders , Nurminen Leena , Horppila Jukka
Published: November 2016

The coexistence of competing species relies on niche partitioning. Competitive exclusion is likely inevitable at high niche overlap, but such divide between competitors may be bridged if environmental circumstances displace competitor niches to enhance partitioning. Foraging‐niche dimension can be influenced by environmental characteristics, and if competitors react differently to such conditions, coexistence can be facilitated. We here experimentally approach the partitioning effects of environmental conditions by evaluating the influence of water turbulence on foraging‐niche responses in two competing fish species, Eurasian perch Perca fluviatilis and roach Rutilus rutilus, selecting from planktonic and benthic prey. In the absence of turbulence, both fish species showed high selectivity for benthic chironomid larvae. R. rutilus fed almost exclusively on zoobenthos, whereas P. fluviatilis complemented the benthic diet with zooplankton (mainly copepods). In turbulent water, on the other hand, the foraging‐niche widths of both R. rutilus and P. fluviatilis increased, while their diet overlap simultaneously decreased, caused by 20% of the R. rutilus individuals turning to planktonic (mainly bosminids) prey, and by P. fluviatilis increasing foraging on littoral/benthic food sources. We show that moderate physical disturbance of environments, such as turbulence, can enhance niche partitioning and thereby coexistence of competing foragers. Turbulence affects prey but not fish swimming capacities, with consequences for prey‐specific distributions and encounter rates with fish of different foraging strategies (pause‐travel P. fluviatilis and cruise R. rutilus). Water turbulence and prey community structure should hereby affect competitive interaction strengths among fish species, with consequences for coexistence probability as well as community and system compositions.
A landscape‐scale field experiment reveals the importance of dispersal in a resource‐limited metacommunity
Authors: Lancaster Jill , Downes Barbara J.
Published: November 2016

Dispersal may play a strong role in driving species diversity across landscapes. Theoretically, dispersal permits species to remain extant within a metacommunity, even if they are periodically excluded from some local communities. Field tests of dispersal effects are difficult, and most non‐experimental data suggest that environmental conditions play the predominant role in setting species diversity. However, most such studies cannot differentiate between patterns caused primarily by dispersal constraints vs. abiotic factors vs. biotic constraints (e.g., priority effects). In 22 km of a sand‐bed stream in southeastern Australia, strong longitudinal gradients in the abiotic environment and detritus densities (resources) mean that downstream locations have abiotic conditions that may be physiologically stressful, low resource densities and low species diversities. We experimentally increased the retention of detritus over 40 m stream lengths along the gradient, with other sites acting as controls. If dispersal is constrained, or abiotic or biotic factors primarily control community structure, then we predicted that increasing resources would result in no change in species composition. Alternatively, if dispersal is common, we predicted that species diversity would increase at treatment sites through colonization by species able to tolerate abiotic conditions downstream and able to invade established communities. Invertebrates were sampled prior to manipulation and then four times (1, 4, 9 and 12 months) following manipulation. Detrital standing stocks increased by an order of magnitude at treatment sites. Over 1 yr, invertebrate densities and species richness also increased in treatment sites. Effect sizes were strong in middle and downstream areas, which were colonized by upstream species. Thus, faunal composition of the downstream treatment sites became more similar to upstream locales, and β‐diversity across treatment sites declined as α‐diversity increased. Out of 54 common taxa, roughly half responded to the experiment; responders and non‐responders had similar proportions of upstream specialists and of different functional feeding groups. Contrary to many non‐experimental studies, our results demonstrate that extensive dispersal can be very important and, for many species, potentially more important than the abiotic environment or biotic constraints in affecting community structure when adequate resources are available.
Mitochondrial reactive oxygen species suppress humoral immune response through reduction of CD19 expression in B cells in mice
Authors: Ogura Masato , Inoue Takeshi , Yamaki Junko , Homma Miwako K. , Kurosaki Tomohiro , Homma Yoshimi
Published: November 2016

Reactive oxygen species (ROS) are implicated in the modulation of diverse processes including immune responses. To evaluate the effects of metabolic ROS produced by mitochondria on B‐cell function and development, we created transgenic (Tg) mice expressing a phosphorylation‐defective mutant of succinate dehydrogenase A in B cells (bSDHAY215F). Splenic B cells in male, but not female, bSDHAY215F mice produced three times more ROS than those in the control mice, and had decreased production of IgM, IgG1, and IgG3, and affinity maturation of IgG1 against T‐cell‐dependent antigens. Following immunization, the male bSDHAY215F mice further displayed suppressed germinal center (GC) formation, and proliferation of GC B cells. Signaling analysis revealed defects in the intrinsic BCR responses, such as activation of Lyn, Btk, and PLCγ2, thus resulting in reduced intracellular Ca2+ mobilization. Notably, the expression levels of B‐cell co‐receptor CD19 and its interaction with Lyn after BCR ligation were significantly reduced in B cells from male bSDHAY215F mice. These results suggest that mitochondrial ROS suppress humoral immune responses through reduction of CD19 expression and resultant BCR signaling in B cells. Therefore, B‐cell immunity may be more labile to oxidative stress in male mice than in female mice.
Interference‐free mass spectrometric detection of capillary isoelectric focused proteins, including charge variants of a model monoclonal antibody
Authors: Hühner Jens , Jooß Kevin , Neusüß Christian
Published: November 2016

CIEF represents an elegant technique especially for the separation of structural similar analytes, whereas MS is a state‐of‐the‐art instrumentation for the identification and characterization of biomolecules. The combination of both techniques can be realized by hyphenating CIEF with CZE‐ESI‐MS applying a mechanical valve. During the CZE step, the remaining ESI‐interfering components of the CIEF electrolyte are separated from the analytes prior to MS detection. In this work, a multiple heart‐cut approach is presented expanding our previous single heart‐cut concept resulting in a dramatical reduction of analysis time. Moreover, different sample transfer loop volumes are systematically compared and discussed in regard to peak width and transfer efficiency. With this major enhancement, model proteins (1.63–9.75 mg/L), covering a wide pI range (5–10), and charge variants from a deglycosylated model antibody were analyzed on intact level. The promising CIEF‐CZE‐MS setup is expected to be applicable in different bioanalytical fields, e.g. for the fast and information rich characterization of therapeutic antibodies.
A Tubular Polymer Redox Flow Battery with a Ceramic Membrane
Authors: Stolze Christian , Schmerbauch Christoph , Friebe Christian , Schubert Ulrich S.
Published: November 2016

A tubular cell design for redox flow batteries is introduced utilizing chemically, mechanically, and thermally stable ceramic membranes. The basic viability of this new cell design is demonstrated via static and pumped charge and discharge experiments with a laboratory prototype. Electrochemical impedance spectroscopy measurements are presented for the investigation of the internal Ohmic resistance. The technological benefits of a tubular cell design as well as its limitations are discussed.
Effect of spices formulations on the physicochemical and sensory properties ofNnam gon, a Cameroonian dish prepared with cucurbitaceae seeds
Authors: Manejo Djiogue Josiane E. , Nguimbou Richard M. , Tatsadjieu Leopold N. , Mang Yannick D. , Njintang Nicolas Y.
Published: November 2016

Nnam gon, a cake made by steam cooking a mixture of Cucurbitaceae seeds paste and others ingredients specially spices, is a highly prized dish in Central African region. A preliminary investigation conducted as part of this study highlighted that formulations used in the processing ofNnam gonvary according to the spices used. This study was carried out to determine the best formulation for the preparation of this dish. For this purpose,Nnam gonsamples were produced from four formulations which differ according to the number of spices used: F0 (no spices); F1 (0.91 g ofAllium cepapaste); F2 (0.88 g ofA. cepapaste, 0.35 g ofAllium sativumpaste, 0.41 g of freshOfficinale zingiberpaste, 0.41 g of freshPetroselinum crispumpaste, 0.33 g ofMonodora myristica, 0.48 g of freshCelery graveolenspaste, 1.19 g of freshAllium porrumpaste, 0.13 g ofAllium lepidophylluspowder, and 0.13 g ofPiper nigrum), and F3 (0.90 g ofA. cepapaste, 0.35 g ofA. sativumpaste, and 0.42 g of freshO. zingiberpaste). The samples were evaluated for their physicochemical characteristics and sensory profile (Quantitative Descriptive Analysis). The results revealed that proteins (16.56–17.38%), carbohydrates (4.71–5.10%), lipids (23.14–24.25%), ash (4.03–5.92%), and fibers (2.17–2.68%) increased significantly (p < .05) with spices adding. The increase in polyphenols (310.55–592.80 mg/100 g FM) and phytates (2.23–12.49 mg/100 gFM) contents was positively correlated with antioxidant properties ofNnam gonwhich also increased with spices adding. Significant differences were observed between the samples for all attributes generated (appearance, odor, taste, flavor, texture, and oral texture). Spices adding induced a decrease in hardness, cohesivity, elasticity, and granulous of cake but enhanced oily.Nnam gonproduced with spicy formulation (F2 and F3) had higher mean score for general acceptance which was highly correlated (p < .05) with spice odor (r = .99), spice taste (r = .92), and color (r = .84). From this study, it is suggested that spicy Cucurbitaceae paste could improve nutritional value, antioxidant properties, and general acceptance ofNnam gon.
Degradation behaviors of geometric cues and mechanical properties in a 3D scaffold for tendon repair
Authors: Wu Yang , Wong Yoke San , Fuh Jerry Ying Hsi
Published: November 2016

A three‐dimensional (3D) scaffold fabricated via electrohydrodynamic jet printing (E‐jetting) and thermally uniaxial stretching, has been developed for tendon tissue regeneration in our previous study. In this study, more in‐depth biological test showed that the aligned cell morphology guided by the anisotropic geometries of the 3D tendon scaffolds, leading to up‐regulated tendious gene expression including collagen type I, decorin, tenascin‐C, and biglycan, as compared to the electrospun scaffolds. Given the importance of geometric cues to the biological function of the scaffolds, the degradation behaviors of the 3D scaffolds were investigated. Results from accelerated hydrolysis showed that the E‐jetted portion followed bulk‐controlled erosion, while the unaixially stretched portion followed surface‐controlled erosion. The 3D tendon scaffold exhibited consistency between the weight loss and the decline of mechanical properties, which indicated by a 65% decrease in mass with a corresponding 56% loss in ultimate tensile strength after degradation. This study not only reveals that the anisotropic geometries of 3D tendon scaffold could affect cell morphology and lead to desired gene expression toward tendon tissue but also gives an insight into how the degradation impacts geometric cues and mechanical properties of the as‐fabricated scaffold. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1138–1149, 2017.
Osteoblast response to the surface topography of hydroxyapatite two‐dimensional films
Authors: Yang Gai , Liu Zili , Guo Yuming , Zhang Jie , Li Han , Shi Weike , Feng Jing , Wang Kui , Yang Lin
Published: November 2016

In the current study, three hydroxyapatite two‐dimensional films with similar wettability but different topological roughness have been prepared through a facile one‐step method using hydrated polylactic acid discs as substrates. The results indicated that the protein adsorption capabilities of the hydroxyapatite two‐dimensional films and the proliferation of osteoblast cells on the as‐prepared films increased obviously with the increase of the films' roughness. These reveal that the cellular responses to two‐dimensional materials can be efficiently tuned by easily adjusting the topological roughness. This finding affords an efficient strategy to regulate the cellular response to bioinorganic two‐dimensional materials and significantly expanded their application potentials in tissue engineering. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 991–999, 2017.
Interactive Effect of Corticosterone and Lactate on Regulation of Testosterone Production in Rat Leydig Cells
Authors: Chen Chih‐Chieh , Chen Chien‐Wei , Lin Po‐Han , Chou Jou‐Chun , Weng Ting‐Chun , Jian Cai‐Yun , Hu Sindy , Lai Wei‐Ho , Lieu Fu‐Kong , Wang Shyi‐Wu , Wang Paulus S.
Published: November 2016

The increasing intensity of exercise enhanced corticosterone and lactate production in both humans and rodents. Our previous studies also demonstrated that lactate could stimulate testosterone production in vivo and in vitro. However, the production of testosterone in response to combined corticosterone and lactate on Leydig cells, and underlying molecular mechanisms are remained unclear. This study investigated the changes in testosterone levels of Leydig cells upon exposure to lactate, corticosterone or combination of both, and revealed the detailed mechanisms. Leydig cells were isolated from rat testes, and treated with different concentrations of lactate (2.5–20 mM), cortiosterone (10−9–10−4 M) and lactate plus corticosterone. The production of testosterone were assayed by radioimmunoassay, and the key molecular proteins, including luteinizing hormone receptor (LHR), protein kinase A (PKA), steroidogenic acute regulatory protein (StAR), and cholesterol P450 side‐chain cleavage enzyme (P450scc) involved in testosterone production were performed by Western blot. Results showed that testosterone levels were significantly increased with lactate, while decresed with corticosterone and lactate plus corticosterone treatment. Protein expressions of LHR and P450scc were upregulated with lactate treatment. However, PKA and P450scc were downregulated by lactate plus corticosterone treatment. This downregulation was followed by decreased testoterone levels in Leydig cells. Furthermore, acetylated cAMP, which activates testosterone production was increased with lactate, but not altered by conrtiosterone. Our findings conclude that corticosterone may interfere with lactate, and restrict lactate‐stimulated testosterone production in Leydig cells. J. Cell. Physiol. 232: 2135–2144, 2017. © 2016 Wiley Periodicals, Inc.
Modulation of Chloride Currents in Human Lung Epithelial Cells Exposed to Exogenous Oxidative Stress
Authors: Canella Rita , Martini Marta , Borriello Roberta , Cavicchio Carlotta , Muresan Ximena M. , Benedusi Mascia , Cervellati Franco , Valacchi Giuseppe
Published: November 2016

Air pollution continues to be a major public health concern affecting 9 out of 10 individuals living in urban areas worldwide. Respiratory tract is the organ most exposed to gas pollution, and ozone has been shown to be one of the most noxious pollutants to which living organisms are exposed. In the present work, we have investigated the effects of 0.1 ppm of ozone on chloride currents in human lung epithelial cells (A549 line) and whether this effect could be modulated by vitamin E pre‐treatment. Whole‐cell patch clamp technique was applied to not excitable cells in order to obtain information about chloride currents behavior, important for epithelial lung cells homeostasis. Significant alteration of the I–V curve after ozone treatment was observed, with the appearance of a large outward rectifier component decreasing over time and returning to the basal state levels after 24 h. Statistical analysis indicated a modification of the amount of ions passing the membrane in the unit of time as a possible cause of this difference. RT‐qPCR analysis showed an increase in ClC‐2 and ORCC mRNA after ozone exposure. In addition, pre‐treatment with vitamin E was able to suppress the outward rectifier component induced by ozone, bringing back the current values to the control level and preventing ozone induced chloride channels up regulation. Our data suggest that ozone exposure is able to modify chloride current density and the use of vitamin E can prevent the above‐mentioned damage. J. Cell. Physiol. 232: 1817–1825, 2017. © 2016 Wiley Periodicals, Inc.
The role of risk and protective factors in the modification of risk for sexual victimization, sexual risk behaviors, and survival sex among homeless youth: A meta‐analysis
Authors: Heerde Jessica A. , Hemphill Sheryl A.
Published: November 2016

Youth homelessness is a multifaceted and significant social problem. For many homeless youth, the risk for exposure to sexual exploitation is high, with the experience of sexual victimization and engaging in sexual risk behaviors and survival sex commonplace. This meta‐analysis appraised internationally published literature to investigate the role of risk and protective factors in modifying the occurrence of sexual victimization, sexual risk behaviors, and survival sex among homeless youth. A comprehensive search of psychology, sociology, medicine, health, and criminology electronic abstraction databases was conducted for the period 1990–2016. Search terms included “homeless,” “rape,” “sexual victimization,” “unsafe sex,” and “survival sex.” The perpetration of sexual offences was included in the search strategy. Eighteen studies, examining sexual victimization, sexual risk behavior, and survival sex, met the inclusion criteria and were included in the meta‐analysis. All but two studies were conducted in the United States. No retrieved studies examined sexual offending; hence, this could not be included in the meta‐analysis. Findings showed that substance use, exposure to violence and crime (as victims and perpetrators), childhood abuse, sexual behavior, and peers' antisocial and sexual behavior were unique factors increasing the likelihood for each of sexual victimization, engagement in sexual risk behavior, and engagement in survival sex. Protective factors were peer and family social support. Moderator analyses showed that the influence of risk factors may differ based on study design, sample size, study country of origin, and participant age and gender. Findings suggest that risk and protective factors may be important mechanisms by which to modify the occurrence of adverse sexual behavior outcomes and better contextualize prevention and early intervention strategies for homeless youth.
Effect of high hydrostatic pressure on the enzymatic hydrolysis of bovine serum albumin
Authors: De Maria Serena , Ferrari Giovanna , Maresca Paola
Published: November 2016

BACKGROUND

The extent of enzymatic proteolysis mainly depends on accessibility of the peptide bonds, which stabilize the protein structure. The high hydrostatic pressure (HHP) process is able to induce, at certain operating conditions, protein displacement, thus suggesting that this technology can be used to modify protein resistance to the enzymatic attack. This work aims at investigating the mechanism of enzymatic hydrolysis assisted by HHP performed under different processing conditions (pressure level, treatment time). Bovine serum albumin was selected for the experiments, solubilized in sodium phosphate buffer (25 mg mL−1, pH 7.5) with α‐chymotrypsin or trypsin (E/S ratio = 1/10) and HPP treatment (100–500 MPa, 15–25 min).

RESULTS

HHP treatment enhanced the extent of the hydrolysis reaction of globular proteins, being more effective than conventional hydrolysis. At HHP treatment conditions maximizing the protein unfolding, the hydrolysis degree of proteins was increased as a consequence of the increased exposure of peptide bonds to the attack of proteolytic enzymes. The maximum hydrolysis degree (10% and 7% respectively for the samples hydrolyzed with α‐chymotrypsin and trypsin) was observed for the samples processed at 400 MPa for 25 min. At pressure levels higher than 400 MPa the formation of aggregates was likely to occur; thus the degree of hydrolysis decreased.

CONCLUSION

Protein unfolding represents the key factor controlling the efficiency of HHP‐assisted hydrolysis treatments. The peptide produced under high pressure showed lower dimensions and a different structure with respect to those of the hydrolysates obtained when the hydrolysis was carried out at atmospheric pressure, thus opening new frontiers of application in food science and nutrition. © 2016 Society of Chemical Industry
Chemical composition of microalgae Heterochlorella luteoviridis and Dunaliella tertiolecta with emphasis on carotenoids
Authors: Diprat Andressa Bacalau , Menegol Tania , Boelter Juliana Ferreira , Zmozinski Ariane , Rodrigues Vale Maria Goreti , Rodrigues Eliseu , Rech Rosane
Published: November 2016

BACKGROUND

Microalgae have been used as food supplements owing to their high protein, polyunsaturated fatty acid and carotenoid contents. As different carotenoids have distinct properties and the carotenoid composition of microalgae has been poorly explored in the literature, this study determined the complete carotenoid composition of two microalgae species, Heterochlorella luteoviridis and Dunaliella tertiolecta, using high‐performance liquid chromatography coupled with diode array detection and tandem mass spectrometry (HPLC‐DAD/MS2). Additionally, the proximate composition and major minerals were evaluated.

RESULTS

The carotenoid composition of the two microalgae was similar, with 13 carotenoids being found in H. luteoviridis and 12 in D. tertiolecta. The major carotenoids were all‐trans‐lutein (1.18 mg g−1 in H. luteoviridis and 1.59 mg g−1 in D. tertiolecta), all‐trans‐violaxanthin (0.52 mg g−1 in H. luteoviridis and 0.45 mg g−1 in D. tertiolecta) and all‐trans‐β‐carotene (0.50 mg g−1 in H. luteoviridis and 0.62 mg g−1 in D. tertiolecta). All‐trans‐lutein was the predominant carotenoid in both microalgae, representing around 40% (mass fraction) of the total carotenoids. The lutein content found in these microalgae was significantly higher (2–40 times) than that in other important food sources of lutein (e.g. parsley, carrot, red pepper and broccoli).

CONCLUSION

The microalgae H. luteoviridis and D. tertiolecta are excellent sources of lutein that could be commercially exploited by the food and pharmaceutical industries. Moreover, it was confirmed that both microalgae are good sources of protein, lipids and calcium. © 2016 Society of Chemical Industry
Effect of high‐pressure processing and thermal pasteurization on overall quality parameters of white grape juice
Authors: Chang Yin‐Hsuan , Wu Sz‐Jie , Chen Bang‐Yuan , Huang Hsiao‐Wen , Wang Chung‐Yi
Published: November 2016

BACKGROUND

The aim of this study was to investigate the microbial levels, physicochemical and antioxidant properties and polyphenol oxidase (PPO) and peroxidase (POD) activities as well as to conduct a sensory analysis of white grape juice treated with high‐pressure processing (HPP) and thermal pasteurization (TP), over a period of 20 days of refrigerated storage.

RESULTS

HPP treatment of 600 MPa and TP significantly reduced aerobic bacteria, coliform and yeast/mold counts. At day 20 of storage, HPP‐600 juice displayed no significant differences compared with fresh juice in terms of physicochemical properties such as titratable acidity, pH and soluble solids, and retained less than 50% PPO and POD activities. Although significant differences were observed in the color, antioxidant contents and antioxidant capacity of HPP‐treated juice, the extent of these differences was substantially lower than that in TP‐treated juice, indicating that HPP treatment can better retain the quality of grape juice. Sensory testing showed no significant difference between HPP‐treated juice and fresh juice, while TP reduced the acceptance of grape juice.

CONCLUSION

This study shows that HPP treatment maintained the overall quality parameters of white grape juice, thus effectively extending the shelf life during refrigerated storage. © 2016 Society of Chemical Industry
Phytate/calcium molar ratio does not predict accessibility of calcium in ready‐to‐eat dishes
Authors: Erba Daniela , Manini Federica , Meroni Erika , Casiraghi Maria C
Published: November 2016

BACKGROUND

Phytic acid (PA), a naturally occurring compound of plant food, is generally considered to affect mineral bioavailability. The aim of this study was to investigate the reliability of the PA/calcium molar ratio as a predictive factor of calcium accessibility in composed dishes and their ingredients.

RESULTS

Dishes were chosen whose ingredients were rich in Ca (milk or cheese) or in PA (whole‐wheat cereals) in order to consider a range of PA/Ca ratios (from 0 to 2.4) and measure Ca solubility using an in vitro approach. The amounts of soluble Ca in composed dishes were consistent with the sum of soluble Ca from ingredients (three out of five meals) or higher. Among whole‐wheat products, bread showed higher Ca accessibility (71%, PA/Ca = 1.1) than biscuits (23%, PA/Ca = 0.9) and pasta (15%, PA/Ca = 1.5), and among Ca‐rich ingredients, semi‐skimmed milk displayed higher Ca accessibility (64%) than sliced cheese (50%) and Parmesan (38%). No significant correlation between the PA/Ca ratio and Ca accessibility was found (P = 0.077).

CONCLUSION

The reliability of the PA/Ca ratio for predicting the availability of calcium in composed dishes is unsatisfactory; data emphasized the importance of the overall food matrix influence on mineral accessibility. © 2016 Society of Chemical Industry
Sustainability of the grizzly bear hunt in British Columbia, Canada
Authors: Mclellan Bruce N. , Mowat Garth , Hamilton Tony , Hatter Ian
Published: November 2016

The sustainability of the grizzly bear (Ursus arctos) hunt in British Columbia, Canada has been questioned and is a high profile issue, particularly in the media. To investigate the hypothesis that the hunt is unsustainable, we examined the sustainable human‐caused mortality rate for grizzly bears using recent data on vital rates and population projection models and compare these to rates used by the management agency; examined the age and sex ratio of the kill and how the sex ratio changes with age for the entire province, each population unit, and cohorts born each year between 1977 and 1990; summarized population density estimates in hunted population units in British Columbia and compared these to unhunted areas in adjacent jurisdictions; and reviewed case studies of population units that have been highlighted as most likely to have had unsustainable kill levels. Because the natural mortality rate of adult grizzly bears is 1–2% and lower than was estimated when sustainable human‐caused mortality targets were developed, estimated sustainable kill rates are 4–10%, and generally higher than the 4–6% used in British Columbia. We estimated that males have been 3–4 times more vulnerable to being killed by hunters than females, yet males dominate the kill at all ages and the proportion of males increased with age, which is opposite of what is predicted for a heavily hunted population. The average age of female and male grizzly bears killed by hunters increased from 7.1 years and 7.4 years, respectively, in the 1980s to 7.7 years and 8.7 years, respectively, in the 2000s. An average of 107.4 females and 204.9 males per cohort born between 1977 and 1990 were eventually killed by people and recorded, suggesting that many more females than males died for unknown reasons. There have been more population inventories of grizzly bears in British Columbia than in any other jurisdiction. The average density estimate of 21 inventories in hunted areas without salmon (Oncorhynchus spp.) in British Columbia (31.2 bears/1,000 km2) was as high as or higher than nearby unhunted areas. The case studies had the highest kill densities or among the highest kill rates in the province and hunting targets were commonly exceeded and seasons closed or the hunter kill target reduced. Although population inventories in these areas found moderate or even high densities of bears, some are now in decline. Hunter kill data from declining populations had a high proportion of males and these were older, demonstrating that these indices of kill rates are sometimes unreliable. Although more population density, trend, and vital rate measurements would be beneficial, the hypothesis that the grizzly bear hunt has been unsustainable was not supported by our investigation of available information. © 2016 The Wildlife Society.
Evaluating genetic capture‐recapture using a chimpanzee population of known size
Authors: Granjon Anne‐Céline , Rowney Carolyn , Vigilant Linda , Langergraber Kevin E.
Published: November 2016

Genetic capture‐recapture (CR) estimates of population size have potential for aiding the conservation and management of rare or elusive animals. To date, few studies have explored the performance of genetic CR estimates by implementing them in a population of known size. We evaluated the accuracy and precision of genetic CR estimates by genotyping fecal samples collected opportunistically over the territory of a well‐studied group of approximately 190 previously identified and genotyped eastern chimpanzees (Pan troglodytes schweinfurthii) in Kibale National Park, Uganda. We compared the performance of genetic CR estimates based on 3‐month and 3‐year sampling periods to explore the impact of lengthened sample periods, which are expected to increase accuracy and precision of estimates but also increase the chances of violating population closure assumptions. We compared the effects of using spatial and non‐spatial models and equal or heterogeneous detection probabilities upon estimates. Over the 3‐year period, we detected 54% of the group members and produced population size estimates with more accuracy and narrower confidence intervals than the 3‐month sampling period. The population remained effectively closed over the 3 years and detection heterogeneity was linked to age but not sex. Non‐spatial methods estimated group size more accurately than spatially explicit methods, which had a stronger tendency to underestimate population size. This study suggests that genetic CR may produce accurate and precise population size estimates if substantial effort is allocated to sample collection and genotyping. © 2016 The Wildlife Society.
Factors influencing reproductive success in male white‐tailed deer
Authors: Newbolt Chad H. , Acker Peter K. , Neuman Timothy J. , Hoffman Stephanie I. , Ditchkoff Stephen S. , Steury Todd D.
Published: November 2016

Positive relationships between age, sexually selected traits, and male reproductive success have been reported for a number of polygynous ungulates; however, relatively little is known about the factors influencing male reproductive success in ungulate species whose mating system is characterized by tending‐bond behaviors. Broad interest in the genetic consequences of selective harvest supports a greater understanding of the role of these factors as determinants of male reproductive success in important game species (e.g., white‐tailed deer [Odocoileus virginianus]), that exhibit tending‐bond behaviors. We investigated male reproductive success in white‐tailed deer across a range of sex ratios and age structures using a known population of deer housed in a 175‐ha enclosure in central Alabama, USA. We measured age, annual antler size, and annual body size of male white‐tailed deer and assigned paternity to 143 known‐age offspring during 2007–2014. Reproductive success was attributed to a high proportion of males during each of the 6 breeding seasons. Our most supported model indicated that annual body size and antler size of the individual were positively associated with annual male breeding success. The effects of annual antler size were sensitive to changes in mean male age of the herd, with antler size having the greatest effect on male reproductive success under older male age structures. Young (≤1.5 yr) males reproduced most frequently when male age structure was youngest (which correlated with female‐biased sex ratios in this population). Our results suggest that male age structure and sex ratio played a key role in establishing patterns of male reproductive success in white‐tailed deer. Management practices that encourage balanced adult sex ratios and older male age structures (e.g., Quality Deer Management) may promote a highly competitive environment where sexually selected traits are of increased importance to male breeding success. However, the ability of managers to alter herd genetics in a positive or negative direction through selective harvest is limited in white‐tailed deer because of the high proportion of reproducing males. © 2016 The Wildlife Society.
Consistency in coral skeletal amino acid composition offshore of Palau in the western Pacific warm pool indicates no impact of decadal variability in nitricline depth on primary productivity
Authors: Williams Branwen , Thibodeau Benoit , Chikaraishi Yoshito , Ohkouchi Naohiko , Walnum Andrew , Grottoli Andréa G. , Colin Patrick L.
Published: November 2016

The depth of the thermocline and associated nitricline in the western Pacific warm pool (WPWP) vary over time in response to changes in larger ocean‐atmosphere climate patterns. A shoaling of the nitricline in the WPWP brings nitrate‐rich seawater (
 > 4 μmol kg−1) above the base of the euphotic zone, stimulating primary productivity. Here, we test if decadal variability in the nitricline depth is driving changes in regional primary productivity and source nitrate dynamics. We use the nitrogen isotopic composition (δ15N) of amino acids in the skeleton of a proteinaceous coral collected from the base of the euphotic zone in the WPWP. In proteinaceous corals, as in most organic life, the δ15N of phenylalanine matches that of the ambient nitrate while the δ15N of trophic amino acids reflect subsequent trophic transfer of the nitrogen prior to incorporation into the coral's food, suspended particulate organic matter. Consistency of the trophic position of the coral calculated from the δ15N composition of the coral skeletal amino acids over its 56 yr lifespan suggest that decadal variability in nitricline depth and subsequent shifts in nitrate availability to the euphotic zone have not impacted primary productivity offshore of Palau in the WPWP. This is important when considering the current external forcing of Pacific Ocean climate patterns and the resulting impacts on the global carbon cycle in the Palau region of the WPWP.
A theoretical basis for a nanomolar critical oxygen concentration
Authors: Zakem E. J. , Follows M. J.
Published: November 2016

When aerobic microbes deplete oxygen sufficiently, anaerobic metabolisms activate, driving losses of fixed nitrogen from marine oxygen minimum zones. Biogeochemical models commonly prescribe a 1–10μM critical oxygen concentration for this transition, a range consistent with previous empirical and recent theoretical work. However, the recently developed STOX sensor has revealed large regions with much lower oxygen concentrations, at or below its 1–10 nM detection limit. Here, we develop a simplified metabolic model of an aerobic microbe to provide a theoretical interpretation of this observed depletion. We frame the threshold as, the subsistence oxygen concentration of an aerobic microbial metabolism, at which anaerobic metabolisms can coexist with or outcompete aerobic growth. The framework predicts that this minimum oxygen concentration varies with environmental and physiological factors and is in the nanomolar range for most marine environments, consistent with observed concentrations. Using observed grazing rates to calibrate the model, we predict a minimum oxygen concentration of order 0.1–10 nM in the core of a coastal anoxic zone. We also present an argument for why anammox may be energetically favorable at a higher oxygen concentration than denitrification, as some observations suggest. The model generates hypotheses that could be tested in the field and provides a simple, mechanistic, and dynamic parameterization of oxygen depletion for biogeochemical models, without prescription of a fixed critical oxygen concentration.
Spherically Symmetric Solvent is Sufficient to Explain the LCST Mechanism in Polymer Solutions
Authors: Bharadwaj Swaminath , Kumar Palakurissi B. Sunil , Komura Shigeyuki , Deshpande Abhijit P.
Published: November 2016

The mechanism of the lower critical solution temperature (LCST) in thermoresponsive polymer solutions has been studied by means of a coarse‐grained single polymer chain simulation and a theoretical approach. The simulation model includes solvent explicitly and thus accounts for solvent interactions and entropy directly. The theoretical model consists of a single chain polymer in an implicit solvent where the effect of solvent is included through the intrapolymer solvophobic potential proposed by Kolomeisky and Widom. The results of this study indicate that the LCST behavior is determined by the competition between the mean energy difference between the bulk and bound solvent, and the entropy loss due to the bound solvent. At low temperatures, solvent molecules are bound to the polymer and the solvophobicity of the polymer is screened, resulting in a coiled state. At high temperatures the entropy loss due to bound solvent offsets the energy gain due to binding which causes the solvent molecules to unbind, leading to the collapse of the polymer chain to a globular state. Furthermore, the coarse‐grained nature of these models indicates that mean interaction energies are sufficient to explain LCST in comparison to specific solvent structural arrangements.

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A highly compact multiband antenna for Bluetooth/WLAN, WiMAX, and Wi‐Fi applications
Authors: Al‐Khaldi Mohammad
Published: November 2016

Throughout this paper the design, optimization and fabrication of a highly compact, improved multiband IFA (inverted‐F antenna) is presented. The proposed antenna design is poised to operate at 2.3, 2.4, 2.5, 3.5, and 5 GHz for use in Bluetooth/WLAN, WiMAX, and Wi‐Fi applications. At those frequencies, the antenna exhibits good reflection and radiation characteristics. The antenna is highly compact measuring 20 mm (width) × 33 mm (length) × 0.635 mm (thickness). This makes it ideal for conformal and low‐profile applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:77–80, 2017
Design and analysis of monopole patch antenna with triple band rejection characteristics
Authors: Suraj Priyadarshi , Rani Gupta Vibha , Saxena Manish
Published: November 2016

In this paper, a slot loaded ultra wideband monopole patch antenna with triple band‐notched characteristic has been presented. The antenna consists of rectangular patch with three modified inverted U‐shaped slots to create three notches at Wi‐MAX (3.3–3.6 GHz), C‐band (3.7–4.2 GHz), and WLAN (5.15–5.85 GHz) frequencies. Lumped‐element equivalent circuit model and current distribution curves have been used to explain the triple band‐rejection characteristics of the designed antenna. The proposed triple notch structure has been fabricated and tested against simulated data. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:138–142, 2017
Lower limb muscle strength impairment in late‐onset and adult myotonic dystrophy type 1 phenotypes
Authors: Petitclerc Émilie , Hébert Luc J. , Mathieu Jean , Desrosiers Johanne , Gagnon Cynthia
Published: November 2016

Introduction

Lower limb strength has never been characterized separately for late‐onset and adult myotonic dystrophy type 1 (DM1) phenotypes.

Methods

The purpose of this study was to: (1) describe and compare lower limb strength between the 2 DM1 phenotypes; and (2) compare the impairment profiles obtained from 2 assessment methods [manual (MMT) and quantitative (QMT) muscle testing] among 107 patients.

Results

Both MMT and QMT showed more pronounced weakness in the adult phenotype. In the late‐onset phenotype, although MMT showed normal strength, QMT revealed a loss of 11.7%–20.4%. Participants with grade 1 or 2 on the Muscle Impairment Rating Scale had weakness detected using QMT, which suggests earlier muscle impairment than MMT alone would suggest.

Conclusions

To avoid muscle wasting, physical activity recommendations should be made for the late‐onset phenotype and in the early stages of the disease for the adult phenotype. MMT is not recommended for use in clinical trials. Muscle Nerve 56: 57–63, 2017.