bluuebunny/crossref_metadata_2025 huggingface dataset:
Developing and demonstrating inhibitory stimulus control over repetitive behavior
Authors: Tiger Jeffrey H. , Wierzba Brittany C. , Fisher Wayne W. , Benitez Brittany B.
Published: February 2017

Developing inhibitory stimulus control over repetitive behavior minimizes the social and learning disruptions caused by this behavior while allowing individuals to continue to access this source of reinforcement at nonproblematic times. These procedures involve allowing repetitive behaviors to occur in some stimulus conditions (S+) and blocking the repetitive behavior in order to disrupt the response–reinforcer relation in other stimulus conditions (S‐) such that the onset of the S‐ period results in rapid and sustained reductions in repetitive behavior. However, the demonstration of stimulus control exerted by the S‐ has often been confounded with participants' exposure to programmed reductive contingencies (i.e., behavior is reduced due to direct contact with contingencies rather than the programmed antecedent stimuli). The current study both developed and demonstrated the suppressive effects of S‐ presentation upon repetitive behavior with two children diagnosed with autism spectrum disorders. These demonstration techniques involved (a) introducing the S‐ into novel environments without the programmed contingencies that we used to establish discriminative control, (b) evaluating the reductive effects of programmed contingencies with and without the associated discriminative stimuli, and (c) evaluating latencies to the onset of repetitive behavior given S+ and S‐ presentations.
Cross-sectional observational study of the availability of evidence supporting novel implantable devices used in gastrointestinal surgery
Authors: Chapman S J , Shelton B , Maruthappu M , Singh P , McCulloch P , Bhangu A
Published: February 2017

Background

Evidence supporting the implementation of novel surgical devices is unstandardized, despite recommendations for assessing novel innovations. This study aimed to determine the proportion of novel implantable devices used in gastrointestinal surgery that are supported by evidence from RCTs.

Methods

A list of novel implantable devices placed intra-abdominally during gastrointestinal surgery was produced. Systematic searches were performed for all devices via PubMed and clinical trial registries. The primary outcome measure was the availability of at least one published RCT for each device. Published RCTs were appraised using the Cochrane tool for assessing risk of bias.

Results

A total of 116 eligible devices were identified (implantable mesh 42, topical haemostatics 22, antiadhesion barriers 10, gastric bands 8, suture and staple-line reinforcement 7, artificial sphincters 5, other 22). One hundred and twenty-eight published RCTs were found for 33 of 116 devices (28·4 per cent). Most were assessed as having a high risk of bias, with only 12 of 116 devices (10·3 per cent) supported by a published RCT considered to be low risk. A further 95 ongoing and 23 unpublished RCTs were identified for 42 of 116 devices (36·2 per cent), but many (64 of 116, 55·2 per cent) had no evidence from published, ongoing or unpublished RCTs. The highest stage of innovation according to the IDEAL Framework was stage 1 for 11 devices, stage 2a for 23 devices, stage 2b for one device and stage 3 for 33 devices. The remaining 48 devices had no relevant clinical evidence.

Conclusion

Only one in ten novel implantable devices available for use in gastrointestinal surgical practice is supported by high-quality RCT evidence.
Maximizing the functional lifetime of Protein A resins
Authors: Zhang Jennifer , Siva Sethu , Caple Ryan , Ghose Sanchayita , Gronke Rob
Published: February 2017

Protein A chromatography is currently the industry gold‐standard for monoclonal antibody and Fc‐fusion protein purification. The high cost of Protein A, however, makes resin lifetime and resin reuse an important factor for process economics. Typical resin lifetime studies performed in the industry usually examine the effect of resin re‐use on binding capacity, yield, and product quality without answering the fundamental question of what is causing the decrease in performance. A two part mechanistic study was conducted in an attempt to decouple the effect of the two possible factors (resin hydrolysis and/or degradation vs. resin fouling) on column performance over lifetime of the most commonly used alkali‐stable Protein A resins (MabSelect SuRe and MabSelect SuRe LX). The change in binding capacity as a function of sodium hydroxide concentration (rate of hydrolysis), temperature, and stabilizing additives was examined. Additionally, resin extraction studies and product cycling studies were conducted to determine cleaning effectiveness (resin fouling) of various cleaning strategies. Sodium hydroxide‐based cleaning solutions were shown to be more effective at preventing resin fouling. Conversely, cold temperature and the use of stabilizing additives in conjunction with sodium hydroxide were found to be beneficial in minimizing the rate of Protein A ligand hydrolysis. An effective and robust cleaning strategy is presented here to maximize resin lifetime and thereby the number of column cycles for future manufacturing processes. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:708–715, 2017
Composition, Antifungal and Antiproliferative Activities of the Hydrodistilled Oils from Leaves and Flower Heads of Pterocephalus nestorianus Nábělek
Authors: Abdullah Fuad O. , Hussain Faiq H. S. , Mannucci Barbara , Lappano Rosamaria , Tosi Solveig , Maggiolini Marcello , Vidari Giovanni
Published: February 2017

This article reports the first study of the chemical composition, and antifungal and antiproliferative properties of the volatile extracts obtained by hydrodistillation of the flower heads and leaves of the traditional Kurdish medicinal plant Pterocephalus nestorianus Nábělek, collected in the wild. A total of 55 constituents, 43 of the flower heads’ oil (PFO) and 46 of the leaves’ oil (PLO), respectively, were identified by GC/MS, constituting 99.68% and 99.04% of the two oils, respectively. The oils were obtained in 0.15% and 0.10% yields (w/w), respectively, on air‐dried vegetable material. The prevalent constituents of the PFO were α‐terpineol (2.41%), α‐linalool (6.42%), 6,10,14‐trimethylpentadecan‐2‐one (2.59%), myristic acid (24.65%), and lauric acid (50.44%), while the major components of PLO were (E)‐hex‐2‐enal (2.26%), (E)‐hex‐2‐en‐1‐ol (2.04), myristic acid (34.03%), and lauric acid (50.35%). The two oils showed significant inhibitory and fungicidal activities against the medically important fungi Candida albicans, Candida tropicalis, Microsporum canis, and Trichophyton mentagrophytes, with minimum inhibitory concentration ranging from 0.7 to 3.3 mg/ml and minimum fungicidal concentration varying from 1.4 to 6.6 mg/ml. The antiproliferative activity of the two oils was assayed against one normal and six human tumor cell lines. Both oils showed selective cytotoxic activity, with IC50 values ranging from 1.4 to 3.3 μg/ml.
Hybrid Catalysis: A Suitable Concept for the Valorization of Biosourced Saccharides to Value‐Added Chemicals
Authors: Gimbernat Alexandra , Guehl Marie , Capron Mickaël , Lopes Ferreira Nicolas , Froidevaux Renato , Girardon Jean‐Sébastien , Dhulster Pascal , Delcroix Damien , Dumeignil Franck
Published: February 2017

Through biomass valorization, sugars can become a major carbon resource for the production of fuels and chemicals by using catalysis. Hybrid catalysis, a direct combination of biocatalysis and chemocatalysis, may yield innovative solutions. 5‐Hydroxymethylfurfural (5‐HMF) is a platform molecule derived from glucose, for which fructose is a key intermediate. To overcome the thermodynamic enzymatic equilibrium between glucose and fructose, two methodologies based on hybrid catalysis are described herein. In the first method, the glucose isomerase and fructose‐to‐5‐HMF dehydration chemocatalysts are simultaneously implemented in a multiphasic way to imply the complexation and transport of fructose. The second method proposes a route through sorbitol, obtained by the hydrogenation of glucose. Sorbitol is then enzymatically converted into fructose, whereas regeneration of the cofactor is performed in situ with an organometallic complex as a chemocatalyst.
Effect of Atomic Vacancies on the Structure and the Electrocatalytic Activity of Pt‐rich/C Nanoparticles: A Combined Experimental and Density Functional Theory Study
Authors: Le Bacq Olivier , Pasturel Alain , Chattot Raphaël , Previdello Bruno , Nelayah Jaysen , Asset Tristan , Dubau Laetitia , Maillard Frédéric
Published: February 2017

We present a joint experimental and density functional theory (DFT) study on the effect of atomic vacancies on the restructuring of platinum—transition metal alloy nanocatalysts and the associated changes in electrocatalytic activity. Atomic vacancies were introduced into slabs composed of pure Pt monolayers, and the structures were relaxed using the Vienna ab initio simulation package code. Effects of i) the concentration and ii) the spatial distribution of atomic vacancies in the slabs on surface and bulk restructuring were investigated. Highly disordered nanostructures featuring large variations of the in‐plane and out‐of‐plane nearest‐neighbour distances around the mean were observed upon relaxation. These findings were confirmed experimentally by using hollow PtNi/C nanoparticles synthesized by a combination of galvanic replacement and the nanoscale Kirkendall effect (a vacancy‐mediated interdiffusion mechanism). The experimental results also show that hollow PtNi/C nanoparticles feature a combination of oxophilic and oxophobic catalytic sites on their surface and are thus highly active both for electrochemical oxidation and reduction reactions.
Graphene and Their Hybrid Electrocatalysts for Water Splitting
Authors: Li Jiayuan , Zhao Zeqiong , Ma Yuanyuan , Qu Yongquan
Published: February 2017

Water electrolysis is considered a potentially practical technology for massive production of hydrogen with very high purity. Electrocatalytic water splitting achieved by graphene hybrids has been the subject of extensive investigations, in which graphene plays multiple roles as electroactive component and/or functionalized support. In this Minireview, we summarize the recent significant advances in graphene hybrid electrocatalyst development for water‐splitting, especially highlighting the design strategies of graphene hybrids and the roles of graphene as electrocatalyst and/or support. Finally, the remaining challenges and future perspectives on graphene hybrid electrocatalyst design for water‐splitting are also discussed.
Rheological, Thermodynamic, and Gas Solubility Properties of Phenylacetic Acid‐Based Deep Eutectic Solvents
Authors: Altamash Tausif , Atilhan Mert , Aliyan Amal , Ullah Ruh , Nasser Mustafa , Aparicio Santiago
Published: February 2017

Choline chloride + phenylacetic acid‐based deep eutectic solvents are studied. Their most relevant experimental physicochemical properties at different mixing ratios together with the CO2 solubility data obtained in wide pressure and temperature ranges are reported. The presented materials exhibit a significant CO2 capture performance with low corrosion effect when compared with the most common amine‐based CO2 capture agents. Detailed rheological measurements are carried out and various models are applied to describe the dynamic flow behavior of the solvents. The CO2 absorption mechanism is evaluated by studying the behavior of the liquid gas and interface. Due to the advantages of low cost, nontoxicity, and favorable physical properties, these solvents are an environmentally promising alternative for effective CO2 capture technological applications.
Numerical Simulations of Solid Circulation Characteristics in an Internally Circulating Elevated Fluidized Bed
Authors: Hassan Muhammad , Schwarz M. Philip , Rafique Muhammad , Feng Yuqing , Liu Guodong , Witt Peter J. , Wang Shuai , Lu Huilin
Published: February 2017

A twin‐chamber internally circulating elevated fluidized bed (EFB) with one chamber elevated higher than the other within a single vessel is simulated using a two‐fluid model. Two EFB configurations termed as reaction chamber (RC)‐elevated and heat exchange chamber (HEC)‐elevated is evaluated. The effect of chamber elevation, variation of superficial velocities, and interchanging the two chambers are investigated and the results are quantified in terms of solid flux Gs. By increasing the RC gas velocity UR at constant HEC velocity UH, Gs is increased in both EFBs while an opposite behavior is observed by increasing UH at constant UR. Variation of the chamber elevation as well as interchanging the chambers also affects the performance of the two EFBs.
Changes in left ventricular function after spontaneous coronary artery dissection
Authors: Franco Christopher , Starovoytov Andrew , Heydari Milad , Mancini G.B. John , Aymong Eve , Saw Jacqueline
Published: February 2017

Background

Spontaneous healing of spontaneous coronary artery dissection (SCAD) and left ventricular ejection fraction (LVEF) recovery is frequently observed clinically. However, LVEF on presentation and follow‐up imaging has not been described.

Hypothesis

We hypothesize that LV dysfunction improves at follow‐up after initial SCAD presentation.

Methods

We included patients with nonatherosclerotic SCAD prospectively followed at Vancouver General Hospital, who had baseline assessment of LVEF and wall‐motion abnormality (WMA) during their index presentation. A subset of these patients had repeat assessment of their ventricular function at follow‐up. We compared the baseline LVEF and WMA with follow‐up assessments and correlated to long‐term cardiovascular outcomes.

Results

We included 277 SCAD patients who had baseline ventricular assessment performed. The average age was 52.4 ± 9.4 years, and 90.3% were female. All presented with myocardial infarction (24.2% STEMI, 75.8% NSTEMI). At baseline, the mean LVEF was 55.6% ± 9.1% and 72/277 (26.0%) had LVEF <50%. The presence of WMA was observed in 237/277 (85.6%) cases. Of 164 patients with repeat assessments, the baseline LVEF was 54.6% ± 9.2%, with improvement to 60.7% ± 7.2% at follow‐up (P < 0.001). Baseline LVEF of <50% was observed in 29.9%, but only 6.7% had LVEF <50% at follow‐up (P < 0.001). Baseline WMA was observed in 87.2% but decreased to 44.5% at follow‐up (P < 0.001). Multivariable analysis showed that presentation with STEMI (odds ratio [OR]: 2.71, P = 0.001), troponin I >50 µg/L (OR: 1.02, P = 0.005), and SCAD involvement of the LAD (OR: 2.5, P = 0.002) were independent predictors of baseline LVEF <50%.

Conclusions

In our large, prospectively followed SCAD cohort, the majority of patients presented with WMA and had relatively normal LVEF. Over half had subsequent normalization of WMA and LVEF on follow‐up assessment.
Remediation of Emerging Pollutants in Contaminated Wastewater and Aquatic Environments: Biomass‐Based Technologies
Authors: Ncibi Mohamed Chaker , Mahjoub Borhane , Mahjoub Olfa , Sillanpää Mika
Published: February 2017

The emergence of new kinds of pollutants including pharmaceuticals drugs, endocrine disrupting compounds, radionuclides, flame retardants, surfactants, and microbial toxins, to name a few, is posing new and serious challenges to the conventional wastewater treatment techniques, to the extent that the treatment plants are becoming indirect source of pollution. Thus, in order to meet these new environmental threats, tremendous research, and development efforts were and are being made to optimize the efficiency of several remediation techniques. In this review, recent and valuable research works will be presented and discussed concerning the remediation of emerging pollutants in contaminated wastewaters and aquatic environments through biomass‐based technologies, including bio‐adsorption using both terrestrial and marine bioresources and agro‐industrial wastes along with derived activated carbons. Phytoremediation, microbial remediation using bacteria, fungi, yeasts was also reported, in addition to some interesting combination scenarios such as biodegradtion/filtration, adsorption/biodegradation, and adsorption/ozonation. Eco‐friendliness, efficiency, cost‐effectiveness were the main criteria of choice among the rich literature, in order to prove that renewable biomass and its derived products could be the “sustainable core” for single or hybrid water treatment techniques, targeting emerging pollutants.
Financial toxicity in cancer care—Edging toward solutions
Authors: Goldstein Daniel A.
Published: February 2017

Financial toxicity is now a well established and generally accepted toxicity related to cancer care. While policy makers and politicians continue to debate about system‐wide changes, physicians and patients can seek ways to decrease financial toxicity and to incorporate this issue into every decision‐making process.

See also pages 1453‐63.
Single Molecular Junction Study on H2O@C60: H2O is “Electrostatically Isolated”
Authors: Kaneko Satoshi , Hashikawa Yoshifumi , Fujii Shintaro , Murata Yasujiro , Kiguchi Manabu
Published: February 2017

A water molecule exhibits characteristic properties on the basis of hydrogen bonding. In the past decade, single water molecules placed in non‐hydrogen‐bonding environments have attracted growing attention. To reveal the fundamental properties of a single water molecule, endohedral fullerene H2O@C60 is an ideal and suitable model. We examined the electronic properties of H2O@C60 by performing single‐molecule measurements. The conductance of a single molecular junction based on H2O@C60 was found to be comparable to that of empty C60. The observed values were remarkably higher than those obtained for conventional molecular junctions due to the effective hybridization of the π‐conjugated system to the metal electrode. Additionally, the results undoubtedly exclude the possibility of electrostatic contact of entrapped H2O with the carbon wall of C60. We finally concluded that H2O entrapped inside a C60 cage can be regarded as an electrostatically isolated molecule.
An Improved Strategy for the Synthesis of Ethylene Glycol by Oxamate‐Mediated Catalytic Hydrogenation
Authors: Satapathy Anilkumar , Gadge Sandip T. , Bhanage Bhalchandra M.
Published: February 2017

The present study reports an improved approach for the preparation of ethylene glycol (EG) by using carbon monoxide as C1 chemical by a two‐step oxidative carbonylation and hydrogenation sequence. In the first step, oxamates are synthesized through oxidative cross double carbonylation of piperidine and ethanol by using Pd/C catalyst under phosphine ligand‐free conditions and subsequently hydrogenated by Milstein's catalyst (carbonylhydrido[6‐(di‐t‐butylphosphinomethylene)‐2‐(N,N‐diethylaminomethyl)‐1,6‐dihydropyridine]ruthenium(II)). The presented stepwise oxamate‐mediated coupling provides the basis for a new strategy for the synthesis of EG by selective upgrading of C1 chemicals.
Cluster based resource allocation in two‐tier HetNets with hierarchical throughput constraints
Authors: Li Li , Zhou Zhaorong
Published: February 2017

Two‐tier heterogeneous networks (HetNets), formed by deploying small cell base stations (SBSs) over existing macrocells, can enhance the network performance in future fifth generation network. However, the cross‐/co‐tier interference in HetNets also will severely influence the user throughput of both tiers. In this paper, we investigate the resource allocation and interference mitigation problem in cluster based orthogonal frequency division multiple access (OFDMA) two‐tier HetNets. In a typical cluster, one SBS is selected as the cluster head to allocate resources among all small cells to guarantee their throughput requirements. Hybrid access policy enables small cells to suppress the cross‐tier interference and earn additional revenue from macrocells, but it also leads to decrease of available resources for small cell users (SUs). To compensate hybrid access SBSs for their resources loss, we impose hierarchical SU throughput constraints on the optimization problem, which guarantee these small cells more resources than closed access ones. Besides, the cross‐tier interference constraint is also considered to protect the transmissions of macrocell users. Accordingly, a subgradient iteration based resource allocation algorithm is proposed. Numerical results show that the proposed algorithm can satisfy SU throughput constraints of all small cells with different access policies and guarantee quality of service requirements of all accessed macrocell users in hybrid access small cells.
Performance comparison of dual‐hop hybrid decode‐or‐amplify‐forward relay schemes for M‐ary quadrature amplitude modulation burst transmission over Rayleigh fading channels
Authors: Woo Choongchae , Lim Sungmook , Ko Kyunbyoung
Published: February 2017

This paper shows the analytical performance expressions of M‐ary quadrature amplitude modulation burst symbol transmission for hybrid decode‐or‐amplify‐forward (HDAF) relay schemes over quasi‐static Rayleigh‐fading channels. First, we derive the probability density function of the received instantaneous signal‐to‐noise ratio as the simplified form, which is related to all the possible occurrence probabilities of error‐events for M‐ary quadrature amplitude modulation burst transmission. On the basis of the derived probability density function, we express average bit error probability, average symbol error probability, and average burst error rate as closed forms, which can be also applied to both amplify‐and‐forward and adaptive decode‐and‐forward (ADF) schemes. The analysis and simulation results show that HDAF scheme for burst transmission can achieve the performance of ADF scheme with symbol‐by‐symbol transmission, which is the achievable lower bound. Furthermore, the outage probability, the normalized channel capacity, and the goodput performance are also derived as closed forms. The analysis shows the superiority of HDAF scheme to ADF scheme. Comparison with simulations confirms that the derived analytical expressions are accurate over all signal‐to‐noise ratio regions and for different numbers of relays and modulation orders.
Resource efficiency of calcium silicate units
Authors: Lieblang Peter , Konrad Daniela , Vogdt Frank Ulrich , Schäfers Martin , Eden Wolfgang
Published: February 2017

Due to the current importance of sustainability, the federal association of the calcium silicate masonry unit industry has taken intensive interest in the question of the resource efficiency of calcium silicate masonry units and construction and has carried out an extensive investigation to this end. The study subjected all stages of calcium silicate, from raw materials reserves and their extraction, production and use in building to recycling, including all transport routes and energy demands, to detailed analysis and critically examined the sustainability of calcium silicate blocks. The present article explains and evaluates the entire life cycle of calcium silicate masonry units.
Design according to Eurocode 6 in practice
Authors: Schermer Detleff
Published: February 2017

For the structural design of masonry according to Eurocode 6 with the associated German national annex, the simplified method and the further simplified calculation method in Annex A are available. These procedures provide tools that can be used in practice to design standard cases quickly and easily. One feature of the verification of masonry walls under compressive loading is that no bending moments in the walls have to be determined as part of the determination of section forces and moments since the verification of the load‐bearing capacity of the wall is based solely on the acting vertical force. The effects of floor end restraint and buckling are dealt with by simple equations. One new feature of verification according to Eurocode 6 is that the effect of partially supported floors on the load‐bearing capacity of the wall can be included directly. The code is compact and simple to use and the further simplified calculation method is predestined for verification by manual calculation.
Differential expression patterns of two delta‐9‐acyl‐CoA desaturases in Thitarodes pui (Lepidoptera: Hepialidae) during different seasons and cold exposure
Authors: Min Qiang , Cheng Shiyu , Xi Jianfei , Xin Tianrong , Xia Bin , Zou Zhiwen
Published: February 2017

Thitarodes pui larvae have a limited distribution in the Tibetan Plateau and are the host of a parasitic fungus, Ophiocordyceps sinensis. Low temperature is a main environmental stress. However, understanding of T. pui cold adaptation mechanisms is insufficient. Delta‐9‐acyl‐CoA desaturase (D9D) is closely correlated with cold adaptation for many organisms. To further understand the cold adaptation processes in T. pui larvae, two D9Ds, TpdesatA and TpdesatB were sequenced, and expression patterns were investigated during different seasons and cold exposure (under 0°C) in the laboratory. The full lengths of two cDNAs are 1,290 bp and 1,603 bp, and the ORFs encode a polypeptide of 348 and 359 amino acids, respectively. Four transmembrane domains, three conserved histidine residues and five hydrophobic regions exist in these two sequences. The expression level of TpdesatA is up‐regulated in the long‐term cold exposure and negatively correlated with temperature in seasonal patterns. TpdesatB responds to cold temperature in short‐term cold exposure and positively corresponds temporarily in seasonal expression. Two D9Ds may have different substrate specificities, TpdesatA tends to use C16:0 and C18:0 as substrate while TpdesatB prefers C18:0. In conclusion, TpdesatA may play a very important role in T. pui cold tolerance and TpdesatB regulates function in short‐term cold exposure and content change of fatty acids in the body.
Take a holistic view of enrollment to ensure classroom diversity
Authors: Sutton Halley
Published: February 2017

Doug Christiansen, Ph.D., had no idea when he was earning his bachelor's degree in political science that he would go on to get a doctorate in higher education, focusing on budgeting and finance. Christiansen speculated that many people stumble into the enrollment management profession rather than planning for their career to go in that direction.
Chemical Biology Towards Precision Medicine
Authors: Schreiber Stuart L.
Published: February 2017

Organic chemistry is primed to fill a much‐needed gap in our understanding of human biology and disease on the one hand and our ability to treat disease effectively on the other. The key challenge is to discover compounds having the novel mechanisms of action demanded by these new patient‐derived insights.
Vibrational analysis of implants and tissues: Calibration and mechanical spectroscopy of multi‐component materials
Authors: Shah Ruchit G. , DeVore Dale , Pierce Mark C. , Silver Frederick H.
Published: February 2017

Several new methods have been used to non‐destructively evaluate the mechanical properties of materials and tissues including magnetic resonance elastography, ultrasound elastography, optical coherence elastography, and various forms of vibrational analysis. One of the limitations of using these methods is the need to establish a relationship between the modulus measured using each new technique and moduli measured using well‐established techniques such as constant rate‐of‐strain and incremental stress–strain curves. In addition, there are no available methods for analyzing the mechanical properties of the individual components of multi‐component materials. In this article, we present data showing that there is a strong correlation (correlation coefficient >0.9) between the modulus measured using classical uniaxial tensile incremental stress–strain tests and those made using a combination of optical coherence tomography and vibrational analysis. Beyond this, we demonstrate that the moduli of the major structural components of pig skin can be measured using this technique. These results suggest that optical coherence tomography in concert with vibrational analysis can be used to measure the moduli of biological and implant materials without having to determine Poisson's ratio. In addition, each of the moduli of the major fibrous components of pig skin can be measured concurrently using this technique. These results may be useful in the characterization of synthetic implants and tissue derived materials without requiring removal of one or more components that are to be characterized. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1666–1671, 2017.
Functional analysis of bioactivated and antiinfective PDLLA – coated surfaces
Authors: Haidari Selgai , Boskov Marko , Schillinger Ulrike , Bissinger Oliver , Wolff Klaus‐Dietrich , Plank Christian , Kolk Andreas
Published: February 2017

Common scaffold surfaces such as titanium can have side effects; for example, infections, cytotoxicity, impaired osseointegration, or low regeneration rates for bone tissue. These effects lead to poor implant integration or even implant loss. Therefore, bioactive implants are promising instruments in tissue regeneration. Osteoinductive elements—such as growth factors and anti‐infectives—support wound healing and bone growth and thereby enable faster osseointegration, even in elderly patients. In this study, titanium surfaces were coated with a poly‐(d,l‐lactide) (PDLLA) layer containing different concentrations of copolymer‐protected gene vectors (COPROGs) to locally provide bone morphogenetic protein‐2 (BMP‐2) or activated anti‐infective agents, such as chlorhexidine gluconate, triclosan, and metronidazole, to prevent peri‐implantitis. The coated titanium implants were then loaded with osteoblasts, NIH 3T3 fibroblasts, and human mesenchymal stem cells in 96‐well plates. When shielded by COPROGs as a protective layer and resuspended in PDLLA, BMP‐2‐encoding pDNA at relatively low doses (5.63 µg/implant) induced the local expression of BMP‐2. A linear dose dependence, which is common for recombinant growth factors, was not found, probably due to the retention property of the PDLLA surface. PDLLA, in general, successfully retains additional elements, such as osteoconductive growth factors (BMP‐2) and anti‐infective agents, which was demonstrated using metronidazole, and thus prevents the systemic application of excessive doses. These bioactive implant surfaces that provide the local release of therapeutic gene vectors or anti‐infective agents allow the controlled stimulation of the implant and scaffold osseointegration. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1672–1683, 2017.
Influence of oxygen levels on chondrogenesis of porcine mesenchymal stem cells cultured in polycaprolactone scaffolds
Authors: Rodenas‐Rochina Joaquin , Kelly Daniel J. , Gómez Ribelles Jose Luis , Lebourg Myriam
Published: February 2017

Chondrogenesis of mesenchymal stem cells (MSCs) is known to be regulated by a number of environmental factors, including local oxygen levels. The hypothesis of this study is that the response of MSCs to hypoxia is dependent on the physical and chemical characteristics of the substrate used. The objective of this study was to explore how different modifications to polycaprolactone (PCL) scaffolds influenced the response of MSCs to hypoxia. PCL, PCL‐hyaluronic acid (HA), and PCL‐Bioglass®(BG) scaffolds were seeded with MSCs derived from bone marrow and cultured for 35 days under normoxic or low oxygen conditions, and the resulting biochemical properties of the MSC laden construct were assessed. Low oxygen tension has a positive effect over cell proliferation and macromolecules biosynthesis. Furthermore, hypoxia enhanced the distribution of collagen and glycosaminoglycans (GAGs) deposition through the scaffold. On the other hand, MSCs displayed certain material dependent responses to hypoxia. Low oxygen tension had a positive effect on cell proliferation in BG and HA scaffolds, but only a positive effect on GAGs synthesis in PCL and HA scaffolds. In conclusion, hypoxia increased cell viability and expression of chondrogenic markers but the cell response was modulated by the type of scaffold used. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1684–1691, 2017.
Osteoblastic differentiation of periodontal ligament stem cells on non‐stoichiometric calcium phosphate and titanium surfaces
Authors: Winning Lewis , Robinson Leanne , Boyd Adrian R. , El Karim Ikhlas A. , Lundy Fionnuala T. , Meenan Brian J.
Published: February 2017

Bioactive materials offer particular clinical benefits in the field of dental implantology, where differentiation of stem cells towards an osteoblastic lineage is required for osseointegration and appropriate function of implants in vivo. The aim of this study was to evaluate the osteoblastic response of Stro‐1 +ve periodontal ligament stem cells (PDLSCs) to three well‐characterized biomaterial surfaces: an abraded titanium surface (cpTi) control; a polycrystalline titanium surface, with both micro and nanotopography produced by radio frequency magnetron sputtering (TiTi); and the same surface incorporating a sputter deposited calcium phosphate coating (CaP‐TiTi). The CaP‐TiTi surfaces were nonstoichiometric, carbonated, and calcium rich with a Ca/P ratio of 1.74. PDLSCs were grown on each surface in the absence of supplementary osteogneic‐inducing agents. Osteoblastic responses were assessed for up to 21 days in culture by measuring gene expression using real time q‐PCR and via assessment of intracellular alkaline phosphatase (ALP) activity. Gene expression analysis for the CaP‐TiTi surfaces showed a significant late stage up‐regulation of Secreted Phosphoprotein 1. Additionally, there was a significant up‐regulation of the Wnt signaling genes β‐catenin and Wnt Family Member 5 A on days 14 and 21, respectively for the CaP‐TiTi surface. A significant increase in intracellular ALP at day 21 for the CaP‐TiTi surface was also observed. These data suggest that the CaP‐TiTi surfaces provide the bioactive conditions required for direct osteoblastic differentiation of PDLSCs. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1692–1702, 2017.
Mechanism of capsaicin inhibition of aldose reductase activity
Authors: Alim Zuhal , Kilinc Namık , Sengul Bulent , Beydemir Sukru
Published: February 2017

Aldose reductase (AR) inhibitors play a vital importance as a potential therapeutic and preventive medicine when it comes to hyperglycemia associated diabetic complications. Additionally, capsaicin is used as a food additive and a drug in a number of diverse clinical trials. The aim of this study is to determine the in vitro inhibition behavior of capsaicin on AR enzyme activity, which was obtained from different rat tissues (heart, kidney, liver, and brain). We showed that AR was inhibited by capsaicin in the micromolar range and noncompetitive manner in all of the tissues. Ki values of capsaicin were found to be 8.87, 264, 535, and 597, respectively, in heart AR, kidney AR, liver AR, and brain AR. In conclusion, capsaicin may be an effective molecule when used in low concentrations to prevent diabetic complications associated with the polyol pathway.
Cellular Evidence of Exosomes in the Reproductive Tract of Chinese Soft‐Shelled Turtle Pelodiscus sinensis
Authors: Waqas Muhammad Yasir , Zhang Qian , Ahmed Nisar , Yang Ping , Xing Guipei , Akhtar Masood , Basit Abdul , Liu Tengfei , Hong Chen , Arshad Muhammad , Rahman Hafiz Muhammad Saif‐Ur , Chen Qiusheng
Published: February 2017

The oviduct is a location of egg production, fertilization, and sperm storage. While its secretions have broadly attributes toward different physiological functions. We examined the ultrastructure of oviduct epithelium and glands in relation to the secretions, particularly with exosomes origin in Chinese soft‐shelled turtle Pelodiscus sinensis using immunohistochemistry and transmission electron microscopy. The ciliated epithelial and gland cells were involved in the release of exosomes and secretions into lumen throughout the year. The exosomes were either released directly from epithelium or in relation with multivesicular body (MVB). The average size of the particles varies between 50 and 130 nm. These exosomes were also widely distributed in the epithelial ciliated cells and pericytoplasm of glands lumen. Intracellular MVB was characterized by membrane‐bounded exosomes of different sizes. Exosomes were also found in close contact with the cilia and sperm membrane in the lumen, which is suggestive of their fusogenic properties. Immunohistochemistry results showed strong to moderate positive expression of exosomes, in ciliated and gland cells, during January, September, and December, as it is the time of sperm storage in this turtle, whereas they showed moderate to weak level of expression during breeding season (May). This is first study about identification of the exosomes in female turtles. Epithelial and glandular exosomes, intracellular MVB, secretions, and secretory vesicles give this turtle specie a unique secretory morphology and a potential model for investigating the secretory nature of the oviduct.
Generation of Cubic Graphs and Snarks with Large Girth
Authors: Brinkmann Gunnar , Goedgebeur Jan
Published: February 2017

We describe two new algorithms for the generation of all non‐isomorphic cubic graphs with girth at least that are very efficient for and show how these algorithms can be restricted to generate snarks with girth at least k.

Our implementation of these algorithms is more than 30, respectively 40 times faster than the previously fastest generator for cubic graphs with girth at least six and seven, respectively.

Using these generators we have also generated all nonisomorphic snarks with girth at least six up to 38 vertices and show that there are no snarks with girth at least seven up to 42 vertices. We present and analyze the new list of snarks with girth 6.
Metal induced changes in trivalent chromium resistant Alcaligenes faecalis VITSIM2
Authors: Matilda Shiny C. , Shanthi Chittibabu
Published: February 2017

The changes induced in bacterial strains under stress conditions provide an insight into metal resistance strategies. Trivalent chromium resistant bacterium were isolated and identified by 16S rRNA gene sequencing and designated as Alcaligenes faecalis VITSIM2. The growth pattern was monitored. The organism also showed resistance to copper, cadmium, and certain antibiotics. The differentially expressed proteins in SDS PAGE were identified by mass spectrometry as flagellin and 50S ribosomal L36 protein. The morphological changes were identified by scanning electron microscopy. The changes in the cell wall content were estimated by peptidoglycan analysis and transformation of phosphates was detected by 31P NMR. Flow cytometry was employed to measure the membrane integrity, esterase activity and intracellular pH. In conclusion spectrum of proteomic, physiological, and morphological alterations was observed that aid the organism to overcome chromium stress.
Quaternary evolution of the northern North Sea margin through glacigenic debris‐flow and contourite deposition
Authors: Batchelor Christine L. , Ottesen Dag , Dowdeswell Julian A.
Published: February 2017

The Norwegian Channel Ice Stream of the Scandinavian Ice Sheet extended across the northern North Sea margin during the mid‐ to late Quaternary, eroding older sediment from the continental shelf. Consequently, little is known about early Quaternary sedimentation on this margin. We use two‐ and three‐dimensional seismic‐reflection data to investigate changing sediment volumes and sources in the northern North Sea through the Quaternary. The northern North Sea Basin was infilled during the early Quaternary by intercalated glacigenic debris‐flows and contourites, which provide a record of the delivery of glacigenic sediment to the slope and the intensity of North Atlantic thermohaline circulation during early Quaternary glacial–interglacial cycles. The infilling of the basin reduced accommodation and led to the deflection of mid‐ to late Quaternary sediments into the Norwegian Sea, forming the North Sea Fan. Close to the onset of the mid‐Quaternary, the south‐western Scandinavian Ice Sheet margin was drained by an ice stream located beneath Måløy Plateau, 60 km east of the Last Glacial Maximum Norwegian Channel Ice Stream. The southward‐flowing Norwegian Sea Bottom Water current was directed into the partially filled northern North Sea Basin during the early Quaternary, and deflected progressively northwards as the basin became infilled.
Identification of four cornua by ultra‐performance liquid chromatography with time‐of‐flight mass spectrometry coupled with principal component analysis
Authors: Cheng Xian‐Long , Zhang Qian‐Qian , Li Ming‐Hua , Yan Hua , Yu Kun‐Zi , Zhou Jian‐Li , Li Shao‐Ping , Wei Feng , Ma Shuang‐Cheng
Published: February 2017

An ultra‐high performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry method coupled with principal component analysis was developed and applied to the identification of Cornu Antelopis, Cornu Bubali, Cornu Naemorhedi, and Cornu Bovis. The data obtained from the trypsin‐digested samples were subjected to principal component analysis to classify these four cornua. Additionally, marker peptides of the cornua were determined by orthogonal partial least‐squares discriminant analysis, and fragmentation tandem mass spectra of these marker peptides were evaluated. The results from this study indicate that the proposed method is reliable, and it has been successfully applied to the identification of variants of cornua commonly used in traditional Chinese medicine.
Aminosilanized magnetic carbon microspheres for the magnetic solid‐phase extraction of bisphenol A, bisphenol AF, and tetrabromobisphenol A from environmental water samples
Authors: Gong Sheng‐Xiang , Wang Xiao‐Li , Liu Wei , Wang Ming‐Lin , Wang Xia , Wang Zheng‐Wu , Zhao Ru‐Song
Published: February 2017

Aminosilanized magnetic carbon microspheres as a novel adsorbent were designed and fabricated. The adsorbent was used for the magnetic solid‐phase extraction of bisphenols at trace levels from environmental water samples before liquid chromatography with tandem mass spectrometry analysis. The structure, surface, and magnetic behavior of the as‐prepared aminosilanized magnetic carbon microspheres were characterized by elemental analysis, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, powder X‐ray diffraction, and vibrating sample magnetometry. The effects of the experimental parameters were investigated by the Plackett–Burman design, and then the parameters that were significant to the extraction efficiencies were optimized through a response surface methodology. The aminosilanized magnetic carbon microspheres exhibited high adsorption efficiency and selectivity for bisphenols. Under optimal conditions, low limits of detection (0.011–2.22 ng/L), and a wide linear range (2–3 orders of magnitude), good repeatability (4.7–7.8%, n = 5), and reproducibility (6.0–8.3%, n = 3) were achieved. The results demonstrate that the novel adsorbent possesses great potentials in the determination of trace levels of bisphenols in environmental water samples.
Preparation of a monolithic cation‐exchange material with hydrophilic external layers by two‐step reversible addition‐fragmentation chain transfer polymerization
Authors: Lin Shen , Zhang Yingying , Huang Wei , Dong Xiangchao
Published: February 2017

In recent years, the efficient analysis of biological samples has become more important due to the advances of life science and pharmaceutical research and practice. Because biological sample pretreatment is the bottleneck for fast process, material development for efficient sample process in the high‐performance liquid chromatography analysis is highly desirable. In this research, a cation‐exchange restricted access monolithic column was synthesized by a reversible addition‐fragmentation chain transfer polymerization method. Utilizing the controlled/living property of the reversible addition‐fragmentation chain transfer method, a monolithic column of cross‐linked poly(sulfopropyl methacrylate) was prepared first and then linear poly(glycerol mono‐methacrylate) was immobilized covalently on the surface of the polymer. The monolithic material has both functionalities of cation‐exchange and protein exclusion. Protein recovery of 94.6% was obtained after grafting of poly(glycerol mono‐methacrylate) while the cation‐exchange property of the column is still retained. In the study, the relation between the synthetic conditions and properties of the materials was studied. The synthesis conditions including the porogen, monomer concentration, and ratio of monomers/initiator/reversible addition‐fragmentation chain transfer agent were optimized. The study provided a method for the preparation of restricted access monolithic columns: a bifunctional material by reversible addition‐fragmentation chain transfer polymerization method.
Enantioseparation of 3‐phenyllactic acid by chiral ligand exchange countercurrent chromatography
Authors: Tong Shengqiang , Wang Xiaoping , Shen Mangmang , Lv Liqiong , Lu Mengxia , Bu Zhisi , Yan Jizhong
Published: February 2017

3‐Phenyllactic acid is an antimicrobial compound with broad‐spectrum activity against various bacteria and fungus. The observed difference in pharmacological activity between optical isomeric 3‐phenyllactic acid necessitates a method for enantioseparation. Chiral ligand exchange countercurrent chromatography was investigated for the enantioseparation of 3‐phenyllactic acid with a synthesized chiral ligand. A two‐phase solvent system was composed of n‐butanol/hexane/water (0.4:0.6:1, v/v/v) to which N‐n‐dodecyl‐l‐hydroxyproline was added to the organic phase as chiral ligand and cupric acetate was added in the aqueous phase as a transitional metal ion. The influence factors were optimized by enantioselective liquid–liquid extraction. Baseline enantioseparation of racemic 3‐phenyllactic acid by analytical high‐speed countercurrent chromatography was achieved. The optical purities of enantiomeric 3‐phenyllactic acid reached 99.0%, as determined by chiral high‐performance liquid chromatography.
Effects of Underground Pore Fissures on Soil Erosion and Sediment Yield on Karst Slopes
Authors: Dai Quanhou , Peng Xudong , Zhao Longshan , Shao Hongbo , Yang Zhi
Published: February 2017

Underground pore fissure is one of common ways of soil leakage, and the soil loss in underground pore fissure would aggravate the development of rocky desertification in karst areas. A designed steel tank with varied underground pore fissure degrees was used to measure how underground pore fissure affected soil erosion and sediment yield on karst bare slope. We found that sediment yield rates and its distribution ratios obviously differed between the surface and underground. Surface sediment yield rate greatly responded to rainfall intensity conditions, while underground sediment yield rate rarely changed. Both bed rock bareness and underground pore fissure degree had an insignificant effect on both surface and underground sediment yield rate, but the former greatly influenced sediment distribution between the surface and underground. With increasing of bed rock bareness rate, both the average surface and underground sediment yield rates first increased and then decreased. The later posed an effect on underground sediment yield rate, which increased with increase of underground pore fissure degree. With increase of underground pore fissure degree, critical rainfall intensity for producing surface sediment would increase from 0.8–1.3 mm min−1 to 1.3–2.0 mm min−1. The results provide a mechanistic understanding of how underground pore fissure affects soil erosion and sediment production. Copyright © 2017 John Wiley & Sons, Ltd.