bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Full QM Computational Study of the Catalytic Mechanism of α‐1,4‐Glucan Lyases
Authors: Campesato Lara , Marforio Tainah Dorina , Giacinto Pietro , Calvaresi Matteo , Bottoni Andrea 
Published: April 2018

AbstractWe investigated the catalytic mechanism of α‐1,4‐glucan lyases using a full QM DFT approach based on the M06‐2X functional. The reaction profile of the whole catalytic process can be divided into three phases: glycosylation, deglycosylation‐elimination and tautomerization. Glycosylation is a highly asynchronous SN1‐like process with an energy barrier of 10.2 kcal mol−1. A proton moves from the Asp665 residue to the glycosidic oxygen. Asp553 acts as a nucleophile and attacks the anomeric carbon causing the cleavage of the glycosidic bond. Deglycosilation‐elimination is the rate‐determining step of the entire process with an overall barrier of 18.3 kcal mol−1. The final step (restoring the catalyst and tautomerization) occurs rather easily, since the Asp553carboxylate group “assists” the proton transfer in the tautomerization process. Our computations clearly indicate that tautomerization must occur inside the enzyme before leaving the active site rather than in the aqueous solution. Outside of the protein environment the enol‐AF→keto‐AF process “assisted” by a water molecule has a barrier of 35.8 kcal mol−1.
Complexes of O=C=S with Nitrogen Bases: Chalcogen Bonds, Tetrel Bonds, and Other Secondary Interactions
Authors: Alkorta Ibon , Elguero José , Del Bene Janet E. 
Published: April 2018

AbstractAb initio MP2/aug’‐cc‐pVTZ calculations have been carried out to investigate chalcogen‐bond formation through the σ‐hole at S and tetrel‐bond formation through the π‐hole at C in complexes of OCS with a series of nitrogen bases. The binding energies of chalcogen‐ and tetrel‐bonded complexes with the sp‐hybridized bases correlate exponentially with the N−S and N−C distances, respectively. The presence of secondary interactions between an N−H or C−H group of an sp2‐hybridized base and OCS in chalcogen‐bonded complexes decreases the correlation between binding energies and the N−S distance. These secondary interactions are stronger in the tetrel‐bonded complexes with the sp2bases, particularly in the isomers of OCS:imidazole and OCS : N2H2, where they may be described as distorted N−H⋅⋅⋅O or N−H⋅⋅⋅S hydrogen bonds. Charge‐transfer interactions are consistent with the nature of the primary and secondary interactions in these complexes. The in‐plane OCS bending frequencies are blue‐shift in the chalcogen‐bonded complexes, and red‐shifted in the tetrel‐bonded complexes. EOM‐CCSD spin‐spin coupling constants1cJ(N4−S) across chalcogen bonds have absolute values less than 9.0 Hz, while the two‐bond coupling constants2cJ(N4−C) do not exceed 4.0 Hz. These are greater in absolute value that the one‐bond coupling constants1tJ(N4−C) across tetrel bonds that are less than 0.5 Hz at much shorter N−C distances.
Identifying Different Halogen‐/Hydrogen‐Bonding Interaction Modes in Binary Systems that Contain an Acetate Ionic Liquid and Various Halobenzenes
Authors: Xu Jing , Zhou Yu , Deng Geng , Ashraf Hamad , Yu Zhi‐Wu 
Published: April 2018

AbstractThe front cover artwork is provided by the group of Prof. Zhi‐Wu Yu at Tsinghua University. The image shows two different interaction modes between two halobenzenes and an acetate‐based ionic liquid (IL). The IL is a potentially good solvent to halogenated drug molecules. Read the full text of the Article at 10.1002/cphc.201701302.
CFR: A cooperative link failure recovery scheme in software‐defined networks
Authors: Wang Likun , Yao Lin , Xu Zichuan , Wu Guowei , Obaidat Mohammad S. 
Published: April 2018

SummarySoftware‐defined networking that separates the control plane from the data plane is envisioned as a promising technology to enable resilient and flexible network management. Tolerating link failures is a fundamental problem in enhancing such network resilience in software‐defined networking. Reactive and proactive fault tolerant schemes for conventional networks may not well balance the fault recovery time and network performance, since the proactive scheme typically underutilizes resources and the reactive scheme usually incurs a longer recovery time. In this paper, we propose a cooperative link failure recovery scheme to find a fine‐grained trade‐off between resource utilization and recovery time by combining reactive and proactive methods. We formalize the problem of link failure recovery as a multiobjective optimization problem and devise a 2‐stage algorithm for it. The first stage of the algorithm guarantees connectivity restoration in an acceptable recovery interval based on fast failover feature supported in OpenFlow protocol, meanwhile it assigns virtual local area network tags to back up paths for achieving a lower memory consumption. The second stage of the algorithm guarantees the quality of service for different applications by adjusting the backup paths after rapid connectivity restoration. Extensive simulations highlight that cooperative link failure recovery scheme can satisfy both the carrier‐grade recovery requirements and quality of service requirements in terms of delay and network bandwidth.
LTE channel throughput assessment and comparison under different terrain
Authors: Saxena Ankit , Sindal Ravi 
Published: April 2018

SummaryIn evolved UMTS terrestrial radio access network, long‐term evolution is known as the fourth‐generation mobile network with a leading radio performance metric as a throughput and signal‐to‐noise ratio (SNR) that affect the radio links. In this paper, we analytically describe the different long‐term evolution propagation model and measure and compare the throughput and SNR on different Doppler frequencies. To validate the performance of channel, we implement network on 3 standard models, viz, as pedestrian (EPA), vehicular (EVA), and typical urban (ETU) at different Doppler frequency (5, 70, 300, and 750 Hz), and different value of SNR (10, 13, 16, and 19 dB) on downlink channel and measured the channel throughput rate. We conclude that a performance of the channel for high SNR values severely affected by the high value of the Doppler frequency while for the channels at low SNR values is a negligible effect with high Doppler frequency.
A variant of GRK5 is associated with the therapeutic efficacy of repaglinide in Chinese Han patients with type 2 diabetes mellitus
Authors: Shang Zhenhai , Han Feifei , Zhou Xueyan , Bao Zejun , Zhu Jing , Wang Tao , Lu Qian , Du Lei , Li Wei , Lv Dongmei , Yin Xiaoxing 
Published: April 2018

Abstract

Post‐Market Research

We aimed to investigate the impact of G protein‐coupled receptor kinase 5 (GRK5) rs10886471 polymorphism on repaglinide efficacy in Chinese patients with type 2 diabetes mellitus (T2DM). A total of 300 T2DM patients and 210 healthy controls were genotyped for GRK5 rs10886471 on a three‐dimensional polyacrylamide gel‐based DNA microarray. Eighty‐five patients with the same genotypes of cytochrome P450 (CYP) 2C8*3 139Arg and organic anion‐transporting polypeptide 1B1 (OATP1B1) 521TT were randomly selected to orally take repaglinide for eight consecutive weeks. Then, the biochemical indicators and pharmacodynamic parameters were measured before and after repaglinide treatment. The T allelic frequency of GRK5 rs10886471 was higher in T2DM patients than in healthy subjects (p < .01). T2DM patients with genotypes CC and CT at GRK5 rs10886471 had a significant reduction in terms of fasting plasma glucose (FPG) compared with those with genotype TT (p < .01). In addition, the carriers of genotypes CC and CT at GRK5 rs10886471 had higher differential values of postprandial serum insulin (PINS) compared with genotype TT carriers (p < .05). These findings suggest that GRK5 rs10886471 polymorphism may influence the therapeutic efficacy of repaglinide in Chinese Han T2DM patients.
Can Chromatin Accessibility be Exploited for Axon Regeneration?
Authors: Danzi Matt C. , O’Neill Nick , Bixby John L. , Lemmon Vance P. 
Published: April 2018

AbstractSeveral studies have demonstrated that the intrinsic ability of neurons to regenerate their axons can be stimulated by maneuvers that favor the open state of chromatin, such as inhibiting histone deacetylase activity or increasing histone acetyltransferase activity. Taken together, these experiments suggest that axon regenerative ability can be increased by promoting chromatin accessibility. In this article, we assess the direct evidence in the literature for this hypothesis and re‐examine other axon regeneration‐promoting manipulations to see if they provide additional support. We find that several interventions known to enhance intrinsic axonal growth capability also increase chromatin accessibility. Although the support for this correlation is strong in the literature, we conclude with a word of caution about therapeutics attempting to exploit this relationship.
Salivary gland stem cells: A review of development, regeneration and cancer
Authors: Emmerson Elaine , Knox Sarah M. 
Published: April 2018

SummarySalivary glands are responsible for maintaining the health of the oral cavity and are routinely damaged by therapeutic radiation for head and neck cancer as well as by autoimmune diseases such as Sjögren's syndrome. Regenerative approaches based on the reactivation of endogenous stem cells or the transplant of exogenous stem cells hold substantial promise in restoring the structure and function of these organs to improve patient quality of life. However, these approaches have been hampered by a lack of knowledge on the identity of salivary stem cell populations and their regulators. In this review we discuss our current knowledge on salivary stem cells and their regulators during organ development, homeostasis and regeneration. As increasing evidence in other systems suggests that progenitor cells may be a source of cancer, we also review whether these same salivary stem cells may also be cancer initiating cells.
Problematic eating behaviors and psychopathology in patients undergoing bariatric surgery: The mediating role of loss of control eating
Authors: Conceição Eva M. , de Lourdes Marta , Pinto-Bastos Ana , Vaz Ana Rita , Brandão Isabel , Ramalho Sofia 
Published: April 2018

AbstractObjectiveThis study compares different problematic eating behaviors (PEBs; objective [OBE]/subjective [SBE] binge‐eating and compulsive [CG]/noncompulsive [NCG] grazing) in relation to the severity of loss of control (LOC) and psychopathology. We also investigate LOC as a mediator between PEBs and psychopathology.MethodThis cross‐sectional study assessed a group of patients before bariatric surgery (n = 163), and a group of bariatric patients 12 months or more after surgery (n = 131). Face‐to‐face assessment: Eating Disorders Examination for binge‐eating episodes; Rep(eat) for grazing. LOC was measured by five questions answered in a 5‐point Likert scale. Self‐report measures: disordered eating, grazing, negative urgency, depression, anxiety, and stress.ResultsOBEs were reported by 26(8.8%), SBE by 29(9.8%), CG by 35(11.9%), and NCG by 36(12.2%) of patients. The different PEBs differed significantly in the severity of LOC (F(3,120)= 25.81, p < .001). Patients reporting OBEs scored higher and patients with NCG scored lower in most measures than patients with other PEBs. Patients with any PEBs scored higher in all self‐report measures than those not reporting any PEBs, with statistical significance reached for uncontrolled eating (F(4,288)= 20.21, p < .001), emotional eating (F(4,288)= 23.10, p < .001), repetitive eating F(4,288)= 18.34, p < .001), and compulsive grazing (F(4,288)= 27.14, p < .001). LOC was found to be a full mediator between PEBs and psychopathology.DiscussionThere is no evidence that the different PEBs differ in the psychopathology severity, independently of the experience of LOC eating during the eating episodes. We show evidence for the conceptualization of different PEB, including grazing, on a continuous scale of LOC and psychopathology.
Functional diversity is more sensitive to biotic filters than phylogenetic diversity during community assembly
Authors: Khalil Mohammed I. , Gibson David J. , Baer Sara G. , Willand Jason E. 
Published: April 2018

AbstractEcologically important functional traits and phylogenetic relatedness may provide mechanistic insight into biotic filters influencing community assembly. To assess this, we examined the relationship between functional diversity (FD, functional trait relatedness) and phylogenetic diversity (PD, evolutionary relatedness) during grassland restoration. Temporal changes in FD and PD were used to examine the effect of two biotic filters during community assembly: intraspecific variation in dominant species (different population sources) and interspecific variation among subordinate species (phylogenetically distinct species pools). The experimental grassland restoration contained whole plots sown with either cultivars or local ecotypes of three dominant grasses (Sorghastrum nutans, Andropogon gerardii, and Schizachyrium scoparium). Each whole plot contained subplots sown with three phylogenetically distinct pools of subordinate species. Cover of all species was measured in permanent sampling areas for ten years, and 10 functional traits were measured for 88 species, allowing calculation of PD and FD, respectively. Overall, the communities establishing with local ecotypes of the dominant grasses were functionally more dissimilar than when established with cultivars, particularly among the Asteraceae, suggesting competitive exclusion of functionally dissimilar species by cultivars. This result was opposite to our prediction that cultivars through limiting similarity would exclude more similar species more so than would local ecotypes. The effect of the dominant grass population source was contingent upon interactions with species pools. A supplemental propagule addition of functionally dissimilar species four years since initial sowing increased FD, but this effect varied among species pools. A lack of relationship between FD and PD in this system indicated that measuring PD alone without inclusion of functional traits may miss additional factors affecting species coexistence. In addition, the variation in FD between population sources and among species pools indicated that the measured traits were more sensitive to these factors than to their phylogenetic relationships. This analysis of long‐term data from a field experiment showed new consequences of using different seed sources and species pools (as biotic filters), and supplemental seeding on PD and FD of restored grassland. Quantifying relevant functional traits in a phylogenetic framework could help identify plant population sources that enhance coexistence of desirable species.
Effect of Roasting Temperature and Time on the Chemical Composition and Oxidative Stability of Argan (Argania spinosa L.) Oils
Authors: Demnati Dalila , Pacheco Rafael , Martínez Leopoldo , Sánchez Sebastián 
Published: April 2018

The effect of roasting on the chemical composition and oxidative stability of oils extracted from argan (Argania spinosa L. Skeels) kernel is studied, observing changes in the characteristics of oils from unroasted and roasted kernels. Argan kernels are roasted at different temperatures (150, 175, and 200 °C) and times (10, 30, and 50 min), in an electric air roaster, prior to oil extraction using the Abencor system. Phosphorus content (PC) of oils increases significantly when roasting temperature and time increases. Roasting facilitates the transfer of phenolic compounds to argan oil. However, only minor changes in characteristics such as peroxide value and carotenoid content of argan oils occurs when roasting temperature and time are raised. The amount of γ‐tocopherol still remains over 85% of the total tocopherols after roasting at the harshest conditions (200 °C, 50 min). However, the content of each tocopherol (α, γ, and δ) gradually decreases when roasting temperature and time increases, certainly due to their thermal degradation. The oxidative stability of argan oil improves when the roasting temperature and time rise. Simultaneously, significant augmentations (p < 0.05) are observed in the specific extinction coefficients in oils prepared at high roasting temperature. The color intensity of oils increases markedly over 175 °C roasting temperature.Practical Applications: This research shows the importance of roasting for producing edible argan oils since its composition, quality and stability are influenced by the conditions of this process. Energy transfer by convection avoids the direct heat of the flame onto the argan kernel and allows the possibility that less polycyclic aromatic hydrocarbons (PAHs) are formed. Furthermore, roasting parameters (temperature and time) should be quantitatively controlled to obtain a desired quality of edible argan oils. These results may help to improve roasting processing for edible argan oil extraction.The effect of roasting temperature and time has been studied with a view to obtain oils of high quality in relation to their physicochemical properties. In the extraction process of edible argan oil, the kernel roasting is the key step that improves the quality and stability of the product.
Formation of Ester Bound 2‐ and 3‐MCPD and Esterified Glycidol in Deep‐Fried and Pickled Herring Products
Authors: Merkle Sybille , Ostermeyer Ute , Rohn Sascha , Karl Horst , Fritsche Jan 
Published: April 2018

In Germany, the best‐selling fish products are canned and marinated fish products including deep‐fried and pickled herring products. During processing, pre‐salted herring fillets are breaded, deep‐fried, and covered by an aqueous marinade containing vinegar and sodium chloride. For shelf‐life extension, the packaged fish can be pasteurized. Due to the co‐occurrence of sodium chloride and glycerol derivatives such as tri‐ or diacylglycerides, the deep‐frying and pasteurization procedure may lead to the formation of fatty acid esters of 2‐monochloropropane‐1,3‐diol and 3‐monochloropropane‐1,2‐diol (MCPD‐E) and of glycidol (G‐E). Various product as well as process dependent parameters on the formation of MCPD‐E and G‐E in deep‐fried and pickled herring products are studied. The frying‐life of the oil has the strongest effect on the formation of MCPD‐E in herring products. 3‐MCPD‐E contents increases from 341 ± 48 to 1133 ± 194 μg kg−1 lipid in the products after 9 days frying‐life of the oil. Moreover, it is shown that the major proportion of MCPD‐E in these products originates from the deep‐frying oil. The analyses of total polar material and spectrophotometric measurement of the absorption at 420 nm of the deep‐frying oil are identified as suitable screening methods for estimating MCPD‐E contents in deep‐fried and pickled herring products.Practical Applications: Canned and marinated fish products are the best‐selling fish products (28% market share) on the German market. Up to now, no studies regarding the deep‐frying procedure of pickled herring products are published. Deep‐frying has shown to be a process leading to MCPD‐E and G‐E in fish products mainly affected by intake of deep‐frying oil. The knowledge about the effect of process and product based parameters on the formation of MCPD‐E and G‐E in deep‐fried and pickled herring products may be of particular interest for the fish‐processing industry in order to manage that quality issue. Moreover, methods for the assessment of the deep‐frying oil quality such as the analysis of the total polar material (TPM) and the spectrophotometric measurement of the absorption at 420 nm deemed suitable screening methods for estimating the MCPD‐E contents in deep‐fried and pickled herring products.Deep‐frying of pickled herring products leads to the formation of MCPD‐E and G‐E, mainly affected by intake of deep‐frying oil and the frying‐life of the oil. Methods for the assessment of the frying oil quality, such as the analysis of TPM and the spectrophotometric measurement of the absorption, are suitable screening methods for estimating the MCPD‐E contents in deep‐fried fish products.
Stability of Oil‐in‐Water Emulsions Fortified with Enzymatic Hydrolysates from Porcine Plasma Protein
Authors: Niu Haili , Gao Mingkun , Zhang Huan , Kong Baohua , Liu Qian 
Published: April 2018

The oxidative and physical stability of oil‐in‐water emulsions affected by the addition of porcine plasma protein hydrolysates (PPPH) is investigated. The emulsions are prepared by combining a 10 wt.% oil phase with a 90 wt.% aqueous phase containing 1.25 wt.% Tween 20 and PPPH (0, 2.5, 5, 10, and 20 mg mL−1 in the final emulsion). The results show that PPPH effectively inhibited the formation of hydroperoxides, thiobarbituric acid reactive substances, and conjugated dienes (P < 0.05), enhancing the oxidative stability of oil‐in‐water emulsions. Meanwhile, the addition of PPPH results in a remarkable increase in the ζ‐potentials and viscosities (P < 0.05) as well as a significant decrease in the particle sizes (P < 0.05), which is verified by an optical microscope. During storage, PPPH prevents oil droplets from colliding and hinders their coalescence and aggregation, leading to better emulsion stability. These results suggest that the addition of PPPH results in an improvement in the oxidative and physical stability of emulsions.Practical Applications: Food emulsions are thermodynamically unstable systems, so they often lean toward separation into an aqueous and oil phase during storage. Therefore, food manufacturers are challenged to seek desirable ingredients in order to stabilize food emulsion systems. In a previous study, the authors demonstrate that PPPH shows strong radical‐scavenging and Cu2+‐chelation ability. In this present study, it is found that the addition of PPPH reduces lipid oxidation and increases the ζ‐potential and viscosity of emulsions, enhancing the oxidative and physical stability of oil‐in‐water emulsions. Thus, PPPH has the potential for use as a natural antioxidant and stabilizer in food emulsions.PPPH is added to oil‐in‐water emulsions and the stability of the emulsions is investigated. The results show that the addition of 20 mg mL−1 PPPH results in the lowest thiobarbituric acid reactive substances (TBARS) value. The size of oil droplets in the emulsion without PPPH is larger than the emulsion with 20 mg mL−1 PPPH during storage. Therefore, the addition of PPPH improves the stability of emulsions.
Functionalized Carbon Black Nanospheres Hybrid with MoS2 Nanoclusters for the Effective Electrocatalytic Reduction of Chloramphenicol
Authors: Sakthivel Rajalakshmi , Kubendhiran Subbiramaniyan , Chen Shen‐Ming , Ranganathan Palraj , Rwei Syang‐Peng 
Published: April 2018

AbstractSynthesis of nanomaterials using cheap and highly efficient material is an important aspect of nanotechnology. In this present work, we have used the carbon black (CB) as a highly conductive and inexpensive carbonaceous material for the fabrication of the electrochemical sensor. However, the poor dispersion in water obstructs the usage of CB in electrochemical sensor and biosensor applications. Hence, the CB was functionalized by simple reflux method and the functionalized CB (f‐CB) nanospheres hybrids with hydrothermally synthesized MoS2 nanoclusters by simple ultrasonication process. In addition, the various suitable spectrometric techniques used to probe the surface morphology and chemical modification of the prepared materials. The prepared MoS2 and f‐CB nanohybrids (f‐CB/MoS2) applied for the electrocatalytic reduction of toxic chloramphenicol (CAP). Fascinatingly, the f‐CB/MoS2 modified electrode showed a competitive electrocatalytic performance comparing with other modified electrodes. At the optimized condition, the sensor exhibited the LOD about 0.002 μM, wider linear range 0.015 to 1370 μM with the sensitivity of 3400 μA μM−1 cm−2 for the determination of CAP. Moreover, the practical viability of the sensor was exploited in milk powder and honey samples.