bluuebunny/crossref_metadata_2025 huggingface dataset:
Paternal age: Negative impact on sperm genome decays and IVF outcomes after 40 years
Authors: Kaarouch Ismail , Bouamoud Nouzha , Madkour Aicha , Louanjli Noureddine , Saadani Brahim , Assou Said , Aboulmaouahib Smahane , Amzazi Saaid , Copin Henri , Benkhalifa Moncef , Sefrioui Omar
Published: February 2018

This study assessed sperm quality declining on relation to paternal age and its impact on in vitro fertilization (IVF) outcomes in order to estimate the APA (Advanced Paternal Age) cutoff. For this, 83 couples undergoing IVF treatment for male factor infertility were enrolled. The women age was ≤39 years, whereas the men were divided in two groups: APA (n = 41; age ≥ 40 years) and young (Y) (n = 42; age < 40 years). Conventional semen parameters (volume, concentration, motility, vitality, and morphology) were analyzed in the collected sperm samples. Furthermore, sperm genome decays (SGD) was assessed by TUNEL assay (DNA fragmentation), aniline blue staining (chromatin decondensation), and fluorescent in situ hybridization (aneuploidy). No significant difference was found concerning the conventional semen parameters between APA and Y groups. Conversely, SGD analysis showed increased DNA fragmentation; chromatin decondensation and sperm aneuploidy rates in the APA group (respectively, 41%, 43%, and 14% vs. 25%, 23%, and 4% in Y group). IVF outcomes also were affected by paternal age as indicated by the rates of cancelled embryo transfers, clinical pregnancy and miscarriage in the two groups APA and Y (29%, 17%, and 60% vs. 10%, 32%, and 42%). Finally, statistical analysis of the results suggests that the age of 40 should be considered as the APA cutoff during ART attempts.
Pharmacologic treatment of donor cells induced to have a Warburg effect‐like metabolism does not alter embryonic development in vitro or survival during early gestation when used in somatic cell nuclear transfer in pigs
Authors: Mordhorst Bethany R. , Murphy Stephanie L. , Ross Renee M. , Benne Joshua A. , Samuel Melissa S. , Cecil Raissa F. , Redel Bethany K. , Spate Lee D. , Murphy Clifton N. , Wells Kevin D. , Green Jonathan A. , Prather Randall S.
Published: February 2018

Somatic cell nuclear transfer is a valuable technique for the generation of genetically engineered animals, however, the efficiency of cloning in mammalian species is low (1–3%). Differentiated somatic cells commonly used in nuclear transfer utilize the tricarboxylic acid cycle and cellular respiration for energy production. Comparatively the metabolism of somatic cells contrasts that of the cells within the early embryos which predominately use glycolysis. Early embryos (prior to implantation) are evidenced to exhibit characteristics of a Warburg Effect (WE)‐like metabolism. We hypothesized that pharmacologically driven fibroblast cells can become more blastomere‐like and result in improved in vitro embryonic development after SCNT. The goals were to determine if subsequent in vitro embryo development is impacted by (1) cloning pharmacologically treated donor cells pushed to have a WE‐like metabolism or (2) culturing non‐treated donor clones with pharmaceuticals used to push a WE‐like metabolism. Additionally, we investigated early gestational survival of the donor‐treated clone embryos. Here we demonstrate that in vitro development of clones is not hindered by pharmacologically treating either the donor cells or the embryos themselves with CPI, PS48, or the combination of these drugs. Furthermore, these experiments demonstrate that early embryos (or at least in vitro produced embryos) have a low proportion of mitochondria which have high membrane potential and treatment with these pharmaceuticals does not further alter the mitochondrial function in early embryos. Lastly, we show that survival in early gestation was not different between clones from pharmacologically induced WE‐like donor cells and controls.
The impact of a mobile application‐based treatment for urinary incontinence in adult women: Design of a mixed‐methods randomized controlled trial in a primary care setting
Authors: Loohuis Anne M.M. , Wessels Nienke J. , Jellema Petra , Vermeulen Karin M. , Slieker‐ten Hove Marijke C. , van Gemert‐Pijnen Julia E.W.C. , Berger Marjolein Y. , Dekker Janny H. , Blanker Marco H.
Published: February 2018

Aims

We aim to assess whether a purpose‐developed mobile application (app) is non‐inferior regarding effectiveness and cost‐effective when used to treat women with urinary incontinence (UI), as compared to care as usual in Dutch primary care. Additionally, we will explore the expectations and experiences of patients and care providers regarding app usage.

Methods

A mixed‐methods study will be performed, combining a pragmatic, randomized‐controlled, non‐inferiority trial with an extensive process evaluation. Women aged ≥18 years, suffering from UI ≥ 2 times per week and with access to a smartphone or tablet are eligible to participate. The primary outcome will be the change in UI symptom scores at 4 months after randomization, as assessed by the International Consultation on Incontinence Modular Questionnaire UI Short Form. Secondary outcomes will be the change in UI symptom scores at 12 months, as well as the patient‐reported global impression of improvement, quality of life, change in sexual functioning, UI episodes per day, and costs at 4 and 12 months. In parallel, we will perform an extensive process evaluation to assess the expectations and experiences of patients and care providers regarding app usage, making use of interviews, focus group sessions, and log data analysis.

Conclusion

This study will assess both the effectiveness and cost‐effectiveness of app‐based treatment for UI. The combination with the process evaluation, which will be performed in parallel, should also give valuable insights into the contextual factors that influence the effectiveness of such a treatment.
Two‐agent scheduling on a single sequential and compatible batching machine
Authors: Li Shisheng , Cheng T.C.E. , Ng C.T. , Yuan Jinjiang
Published: February 2018

We study two‐agent scheduling on a single sequential and compatible batching machine in which jobs in each batch are processed sequentially and compatibility means that jobs of distinct agents can be processed in a common batch. A fixed setup time is required before each batch is started. Each agent seeks to optimize some scheduling criterion that depends on the completion times of its own jobs only. We consider several scheduling problems arising from different combinations of some regular scheduling criteria, including the maximum cost (embracing lateness and makespan as its special cases), the total completion time, and the (weighted) number of tardy jobs. Our goal is to find an optimal schedule that minimizes the objective value of one agent, subject to an upper bound on the objective value of the other agent. For each problem under consideration, we provide either a polynomial‐time or a pseudo‐polynomial‐time algorithm to solve it. We also devise a fully polynomial‐time approximation scheme when both agents’ scheduling criteria are the weighted number of tardy jobs.
Comparison of Resting Energy Expenditure Assessment in Pediatric Oncology Patients
Authors: Ringwald‐Smith Karen , Hobar Ashley , Flowers Casey , Badgett Katie , Williams‐Hooker Ruth , Roach Robin R. , Sykes April , Lu Zhaohua , Mackert Paul , Mandrell Belinda N.
Published: February 2018

Background: Evaluation of energy requirements is an important part of the nutrition assessment of pediatric oncology patients. Adequate provision of energy in this population is of extreme importance because of the prevalence of malnutrition and its effect on growth, development, quality of life, morbidity, and mortality. Numerous methods are used in clinical practice for estimating the resting energy expenditures (REE), specifically indirect calorimetry and predictive equations. A relatively new instrument used to assess REE is the hand‐held indirect calorimeter. The purpose of this quality improvement project was to compare the accuracy of REE measurements taken by a hand‐held indirect calorimeter and predictive equations to that of a standard indirect calorimeter metabolic cart. Methods: Patients receiving therapy for pediatric cancer, aged 7–18 years, and having a weight ≥15 kg and scheduled for a REE nutrition assessment were eligible. Sequentially, the patient's REE was assessed with the cart and the hand‐held indirect calorimeter along with the predictive equation calculation. Results: Post hoc pairwise comparisons revealed that all 3 methods were significantly different from one another (P < .0001). When compared with the cart, the portable hand‐held calorimeter was found to underestimate REE by 11.9%, whereas predictive equations overestimated REE by 12.4%. Conclusion: Our quality improvement project suggests that the hand‐held indirect calorimeter underestimated REE, and predictive equations overestimated REE in pediatric oncology nutrition assessment. Therefore, we recommend that these limitations in assessment be considered when assessing REE using a hand‐held indirect calorimeter or predictive equations.
Advances in implementation, theoretical motivation, and numerical results for the nested iteration with range decomposition algorithm
Authors: Mitchell Wayne , Manteuffel Tom
Published: February 2018

This paper studies a low‐communication algorithm for solving elliptic PDEs on high‐performance machines, the nested iteration with range decomposition (NIRD) algorithm. Previous work has shown that NIRD converges to a high level of accuracy within a small, fixed number of iterations (usually one or two) when applied to simple elliptic problems. This paper makes some improvements to the NIRD algorithm (including the addition of adaptivity during preprocessing, wider choice of partitioning functions, and modified error measurement) that enhance the method's accuracy and scalability, especially on more difficult problems. In addition, an updated convergence proof is presented based on heuristic assumptions that are supported by numerical evidence. Furthermore, a new performance model is developed that shows increased performance benefits for NIRD when problems are more expensive to solve using traditional methods. Finally, extensive testing on a variety of elliptic problems provides additional insight into the behavior of NIRD and additional evidence that NIRD achieves excellent convergence on a wide class of elliptic PDEs and, as such, should be a very competitive method for solving PDEs on large parallel computers.
A high‐order FEM with exact geometry description for the Laplacian on implicitly defined surfaces
Authors: Gfrerer M.H. , Schanz M.
Published: February 2018

In this paper, a high‐order finite element method for partial differential equations on smooth surfaces is proposed. The surface is defined as the intersection of a rectangular cuboid and an implicitly defined surface. Therefore, the surface of interest may not be closed. The main novel contribution in this work is the incorporation of an exact geometry description of surfaces with boundary into the finite element method. To this end, a piecewise planar triangulation is mapped onto the surface of interest by making use of the implicit surface definition. The mapping uses predefined search directions and can, therefore, be tailored to consider boundaries. High‐order hierarchical shape functions are utilized for the field approximation. They are defined on a reference triangle in the usual way. The proposed method is easy to implement and bypasses the need for a high‐order geometry description. Furthermore, due to the exact geometry, the imposition of Dirichlet boundary conditions, source terms, and mesh refinement are easy to carry out.
An adaptive cracking particle method providing explicit and accurate description of 3D crack surfaces
Authors: Ai Weilong , Augarde Charles E.
Published: February 2018

Cracks in 3‐dimensions (3D) have arbitrary shapes and therefore present difficulties for numerical modelling. A novel adaptive cracking particle method with explicit and accurate description of 3D cracks is described in this paper. In this meshless method, crack surfaces are described by a set of discontinuous segments, which are associated with particles. This group of particles are assumed all to be “cracked” and split into 2 subparticles with modified support domains. Compared to the original method where the spherical supports at particles are equally divided, the proposed method makes use of nonplanar segments to account for changes in crack face direction. The orientations of those segments and the angular changes of cracks during crack propagation steps are recorded using triangular meshes. Supports of weight functions are modified according to those changes so that quasi‐continuous crack surfaces can be obtained, avoiding the spurious cracking seen in earlier cracking particle methods. An adaptive approach in 3D is then introduced to capture stress gradients around crack fronts. Several 3D crack problems with reference results have been tested to validate the proposed method with good agreement being achieved using the new method, showing it to be potentially a significant advance for 3D fracture prediction problems.
Facile synthesis of oligo(4‐methoxyphenol) in water and evaluation of its efficiency in stabilization of polypropylene
Authors: Wu Yufeng , Jiang Fan , Chai Chunxiao , Zheng Ke , Cui Yuanchen , Zhang Lei
Published: February 2018

A hindered polyphenol, oligo(4‐methoxyphenol), has been first successfully synthesized via a mild biocatalytic pathway using horseradish peroxidase as catalyst in water without any additive. Then the efficiency of oligo(4‐methoxyphenol) in stabilization of polypropylene (PP) was evaluated in terms of thermal analysis and accelerated aging test. It was observed that the apparent activation energy for thermal decomposition of PP/oligo(4‐methoxyphenol) calculated by Friedman's method is higher than that of virgin PP. Oligo(4‐methoxyphenol)‐stabilized PP maintains its tensile strength even after aging at 120°C for 800 hours. Oxidation induction time and onset oxidation temperature of PP/oligo(4‐methoxyphenol) are higher than both virgin PP and PP/4‐methoxyphenol, as well as PP stabilized with commercially available 6‐di‐tert‐buty‐4‐methylphenol or 1076. These results indicate that oligo(4‐methoxyphenol) can effectively improve the thermo‐oxidative resistance of PP. Noting that oligo(4‐methoxyphenol) is synthesized via enzymatic polymerization in water under mild condition with a facile procedure, oligo(4‐methoxyphenol) is thus proposed as a new efficiency and readily available antioxidant for PP.
Treatment of premenstrual syndrome: Appraising the effectiveness of cognitive behavioral therapy in addition to calcium supplement plus vitamin D
Authors: Karimi Zahra , Dehkordi Mahnaz Aliakbari , Alipour Ahmad , Mohtashami Tayebeh
Published: February 2018

Premenstrual syndrome (PMS) consists of repetitious physical and psychological symptoms. The symptoms occur during the luteal phase of the menstrual period and cease when the menstrual period starts. This study included pre‐test and post‐test experiments between a control group and a test group. The statistical population involved 40 females, chosen based on multistage cluster sampling. The participants were then divided into four groups to undergo treatment with calcium supplement plus vitamin D together with cognitive behavioral therapy (CBT), and were screened with the Premenstrual Syndrome Screening Test (PSST). The pre‐test and post‐test scores in the PSST, the General Health Questionnaire (GHQ‐28), and Bell's Adjustment Inventory (BAI) were used as assessment tools (p < .05). According to the parameters of PMS symptoms, when evaluating the pre‐test and post‐test scores, the overall score of each individual in the experimental group was improved and a significant effect for the combination of calcium supplement plus vitamin D together with CBT was observed in comparison to the post‐test control group. A comparison of multivariate analysis of covariance (MANCOVA) results collected from the pre‐test and post‐test scores revealed that the method of treatment was beneficial for PMS, adjustment, and general health.
Graft polymerization of 4‐imidazole acrylic acid onto polyurethane for the improvement of water compatibility and antifungal activity
Authors: Chung Yong‐Chan , Kim Ha Youn , Choi Jae Won , Chun Byoung Chul
Published: February 2018

The graft polymerization of 4‐imidazole acrylic acid (IA) onto polyurethane (PU) was conducted to prepare antifungal PU with enhanced water compatibilities. Poly(IA) chains with different IA content were grafted onto PU in an IA series, whereas they were not grafted onto PU in a control CIA series. The carboxyl contents of the IA and CIA series, as determined by acid/base titration, proportionally increased with an increase in the IA feed, but the water contact angles of only the IA series significantly decreased compared with those of the CIA series and plain PU. The maximum tensile stress of the IA series sharply increased because of the chemical linking of the grafted poly(IA) chains, whereas the tensile strain at break was not affected by the grafted poly(IA) chains. The shape recovery of the IA series at 10°C notably improved with the grafting of poly(IA) chains, whereas that of the CIA series did not increase at all. The IA series samples completely suppressed fungal growth on PU because of the grafted imidazole groups and hydrophilic carboxyl groups. POLYM. ENG. SCI., 58:2088–2097, 2018. © 2018 Society of Plastics Engineers
Derivation and Validation of aClostridium difficileInfection Recurrence Prediction Rule in a National Cohort of Veterans
Authors: Reveles Kelly R. , Mortensen Eric M. , Koeller Jim M. , Lawson Kenneth A. , Pugh Mary Jo V. , Rumbellow Sarah A. , Argamany Jacqueline R. , Frei Christopher R.
Published: February 2018

Study Objective

Prior studies have identified risk factors for recurrentClostridium difficileinfection (CDI), but few studies have integrated these factors into a clinical prediction rule that can aid clinical decision‐making. The objectives of this study were to derive and validate aCDIrecurrence prediction rule to identify patients at risk for first recurrence in a national cohort of veterans.

Design

Retrospective cohort study.

Data Source

Veterans Affairs Informatics and Computing Infrastructure.

Patients

A total of 22,615 adult Veterans Health Administration beneficiaries with first‐episodeCDIbetween October 1, 2002, and September 30, 2014; of these patients, 7538 were assigned to the derivation cohort and 15,077 to the validation cohort.

Measurements and Main Results

A 60‐dayCDIrecurrence prediction rule was created in a derivation cohort using backward logistic regression. Those variables significant at p<0.01 were assigned an integer score proportional to the regression coefficient. The model was then validated in the derivation cohort and a separate validation cohort. Patients were then split into three risk categories, and rates of recurrence were described for each category. TheCDIrecurrence prediction rule included the following predictor variables with their respective point values: prior third‐ and fourth‐generation cephalosporins (1 point), prior proton pump inhibitors (1 point), prior antidiarrheals (1 point), nonsevereCDI(2 points), and community‐onsetCDI(3 points). In the derivation cohort, the 60‐dayCDIrecurrence risk for each score ranged from 7.5% (0 points) to 57.9% (8 points). The risk score was strongly correlated with recurrence (R2 = 0.94). Patients were split into low‐risk (0–2 points), medium‐risk (3–5 points), and high‐risk (6–8 points) classes and had the following recurrence rates: 8.9%, 20.2%, and 35.0%, respectively. Findings were similar in the validation cohort.

Conclusion

SeveralCDIand patient‐specific factors were independently associated with 60‐dayCDIrecurrence risk. When integrated into a clinical prediction rule, higher risk scores and risk classes were strongly correlated withCDIrecurrence. This clinical prediction rule can be used by providers to identify patients at high risk forCDIrecurrence and help guide preventive strategy decisions, while accounting for clinical judgment.
Comprehensive branching analysis of polyethylene by combined fractionation and thermal analysis
Authors: Ndiripo Anthony , Eselem Bungu Paul Severin , Pasch Harald
Published: February 2018

Linear low density polyethylene (LLDPE) and low density polyethylene (LDPE) differ significantly in their branching types and branching distributions. For a comprehensive analysis, preparative temperature rising elution fractionation and/or preparative molar mass fractionation are used to fractionate typical LLDPE and LDPE bulk resins into narrowly distributed fractions. The chain structures of the bulk resins and their fractions are further analysed using SEC, crystallization analysis fractionation, DSC and high‐temperature HPLC to provide detailed information on short chain branching in LLDPE and long chain branching in LDPE. For LDPE it is shown that the multiple fractionation approach is a powerful source of sample libraries that may have similar molar masses and different branching structures or alternatively similar branching but different molar masses. The analysis of these library samples by thermal analysis provides a much deeper insight into the molecular heterogeneity of the samples compared to bulk sample analysis. © 2018 Society of Chemical Industry
The social profitability of photovoltaics in Germany
Authors: López Prol Javier , Steininger Karl W.
Published: February 2018

While Germany has led the market in photovoltaic (PV) implementation throughout the last decade, there has been increasing criticism of PV support policies due to their high cost. Although declining, the levelized cost of electricity (LCOE) from PV is still above the German wholesale electricity price. However, using LCOE as an evaluation yardstick falls short in at least 2 respects: It neither takes into account integration costs rising with PV penetration (ie, undervaluing its actual cost) nor avoided externalities of replacing conventional for renewable generation (social cost overvaluation). We thus calculate the social profitability of PV in Germany by including not only private costs and benefits but also integration costs to the electricity system and avoided environmental externalities, using the internal rate of return and the profitability index as indicators. Our results show that when these factors are considered, the social profitability of PV in Germany is higher than 10% at the lower bound of the social cost of carbon (150€/tCO2) up to a penetration level of at least 15% and positive up to a penetration level of at least 25%. Results also show the level of private profitability if all externalities were internalized and assert that subsidies are justified to align private and social profitability. The proposed method could be used as a complementary indicator to private profitability by public institutions, development banks, and companies with social responsibility values.
Dysphagia and associated clinical markers in neurologically intact children with respiratory disease
Authors: Sassi Fernanda C. , Bühler Karina C. B. , Juste Fabiola S. , Almeida Fabiola C. F. , Befi‐Lopes Debora M. , de Andrade Claudia R. F.
Published: February 2018

Objective

The identification of oropharyngeal aspiration is paramount since it can have negative consequences on a compromised respiratory status. Our hypothesis was that dysphagia in neurologically intact children with respiratory disease is associated to specific clinical markers.

Study Design

Using the medical files we conducted a retrospective, observational cohort study on children admitted to the pediatric hospital unit due to respiratory disease. We collected data on specific parameters of a clinical swallowing assessment and dysphagia was classified according to the Dysphagia Management Staging Scale. We also included the following clinical markers: age, days of hospitalization, need for orotracheal intubation (OTI), duration of orotracheal intubation (in hours), number of previous hospital admissions due to respiratory disease, number of previous hospital admissions due to other causes, and previous orotracheal intubations.

Results

The final study sample consisted of 102 patients (mean age of 5.88 months). For the purposes of statistical analysis, the patients were grouped according to the classification of dysphagia (ie, no dysphagia, mild dysphagia, and moderate‐severe dysphagia). Data analysis indicated that the clinical markers of orotracheal intubation (P = 0.042), duration of orotracheal intubation (P = 0.025), and days of hospitalization (P = 0.037) were significant in children with moderate‐severe dysphagia.

Conclusions

Our data indicate that neurologically intact children with respiratory disease who were submitted to prolonged OTI (ie, over 48 h) should be prioritized for receiving a detailed swallowing assessment.
Larvicidal efficacy of Adiantobischrysene from Adiantum latifolium against Oryctes rhinoceros through disrupting metamorphosis and impeding microbial mediated digestion
Authors: Pradeep Kumar Ravindrannair , John Anil , Kumar Praveen , Dinesh Babu Kaleekkal Vasupillai , Evans Dasammal Asirvadam
Published: February 2018

BACKGROUND

Oryctes rhinoceros Linn. (Coleoptera: Scarabaeidae) is a serious pest of coconuts and other palms. Symbiotic gut bacteria play significant roles in the digestion of cellulosic materials as well as in some other physiological processes essential for the existence of O. rhinoceros larvae. The study was undertaken to isolate a compound with antibacterial and larvicidal activities from the leaves of Adiantum latifolium Lam. following a bioassay‐guided method.

RESULTS

Methanol extract (ME) of dry leaf powder of A. latifolium showed larvicidal activity against third‐instar O. rhinoceros (LD50, 5018 mg/kg) with antibacterial activity on its gut microbiota. An in vitro study showed the bacteria Bacillus cereus, Micrococcus lylae, Stenotrophomonas maltophilia, Kocuria rosea, Burkholderia mallei, Staphylococcus epidermidis, S. arlettae and Corynebacterium afermentans identified from the larval gut were sensitive to ME. Bioactivity‐guided isolation of the compound by liquid–liquid extraction and column chromatography resulted in Adiantobischrysene which showed antibacterial and larvicidal activity (LD50, 8.4 mg/kg) and led to weight loss and precocious metamorphosis in larvae. An enzyme immunoassay showed a large peak in 20‐hydroxyecdysone that commits larvae to precocious metamorphosis.

CONCLUSION

This study demonstrated that the antibacterial and metamorphosis disrupting activity of Adiantobischrysene make it a natural pesticidal compound against O. rhinoceros. © 2018 Society of Chemical Industry
Effect of Film Thickness on Photoelectrochemical Performance of SnO2 Prepared via AACVD
Authors: Mohamad Noh Mohamad F. , Soh Mohd F. , Riza Muhammad A. , Safaei Javad , Mohd Nasir Siti N. F. , Mohamad Sapian Norfaizzatul W. , Teh Chin H. , Ibrahim Mohd A. , Ahmad Ludin Norasikin , Mat Teridi Mohd A.
Published: February 2018

Tin (IV) oxide (SnO2) is a stable semiconductor and has been used in a wide range of applications. In this work, aerosol‐assisted chemical vapor deposition (AACVD) technique is employed to deposit SnO2 thin film with different layer thicknesses by controlling the deposition time. The morphological and optical properties of SnO2 layer are investigated thoroughly to understand the relationship between the deposition time and SnO2 performance in photoelectrochemical cells. The bandgap energy of all SnO2 thin films is determined to be 3.65 eV. However, from linear sweep voltammetry (LSV) analysis, it is found that SnO2 layer deposited for 15 min, which produced a layer with thickness of about 50 nm, showed the best photocurrent performance (30.7 µA cm−2 at 1.0 V vs. Ag/AgCl) compared to their thinner or thicker counterparts. The right thickness enables the formation of a film with complete surface coverage, which effectively prevents current leakage and allows optimum light absorption. Besides, electrochemical impedance spectroscopy (EIS) analysis confirms that 50 nm thick SnO2 layer possesses fastest electron transfer property compared to thicker or thinner layers.
Perturbed structures generated using coordinates derived from compliance constants in internal vibrations for QTAIM dual functional analysis: Intrinsic dynamic nature of interactions
Authors: Nakanishi Waro , Hayashi Satoko
Published: February 2018

Perturbed structures for QTAIM dual functional analysis (QTAIM‐DFA) are proposed to generate using the coordinates corresponding to the compliance force constants in internal vibrations (CIV). In QTAIM‐DFA, total electron energy densitiesHb(rc) are plotted versusHb(rc) –Vb(rc)/2 at bond critical points (BCPs) of interactions in question, whereVb(rc) are potential energy densities at BCPs. Each plot of an interaction based on the data from both perturbed structures and fully optimized one takes the form (θp, κp), where θpcorresponds to the tangent line of the plot and κpis the curvature. The θpvalues evaluated with CIV are equal to those obtained by partial optimizations with the interaction distance in question being fixed suitably, within the calculation errors. Very high applicability of CIV is demonstrated to generate the perturbed structures for QTAIM‐DFA. Dynamic nature of interactions based on (θp, κp) with CIV is called “intrinsic dynamic nature of interactions.”
Water adsorption on the surface of Ni‐ and Co‐based layer‐structured cathode materials for lithium‐ion batteries
Authors: Kim Yongseon
Published: February 2018

Ni‐based layer‐structured cathode materials are more vulnerable to moisture than conventional LiCoO2 cathodes, adsorbing more water and easily forming LiOH on the surface. This study investigated the moisture adsorption mechanism on the surface of layer‐structured cathodes. The behavior of water molecules on LiCoO2 and LiNiO2 surfaces were simulated and the structural and chemical changes during the adsorption process were analyzed by first‐principles methods. It was found that the adsorption occurs via two types of mechanism: one involving ionic interactions between Li on the crystal surface and O in the adsorbate, and the other involving covalent bonding between the transition metal (TM) on the surface and O in the adsorbate, which restores the coordination of the TM by recovering its broken bonds. The difference between the water adsorption behaviors of Ni‐based and Co‐based layer‐structured cathodes was found to be mainly due to the ionic‐interaction‐driven adsorption on the (003) surface.
Studies on neuraminidase inhibition
Authors: Paiva Pedro , Costa Inês P. D. , Ferreira Cleide E. , Ferreira Pedro , Pereira Andreia T. , Cerqueira Nuno M. F. S. A. , Fernandes Pedro A. , Ramos Maria J.
Published: February 2018

Neuraminidase (NA) inhibitors are a class of antiviral drugs developed to target the influenza virus— a highly contagious virus that can cause severe respiratory illness and death. Although several NA inhibitors have been developed in the last decade, it is still poorly understood how they interact in the active site of the enzyme and which chemical and structural features potentiate their inhibitory activity. Taking this into account, we analyze in this article the inhibitory activity of 236 known NA inhibitors using molecular docking simulations. The protocol performed in this work, based on AutoDock, demonstrated to be very efficient in differentiating NA inhibitors with ΔGbinding above −11.7 kcal·mol−1. The results have shown that the best inhibitors are those that closely resemble the structure of the natural substrate, but explore additional areas of the active site with which they interact strongly and, therefore, potentiate their inhibitory activity. The best NA inhibitors are characterized by a central saturated six‐member ring filling almost completely the space available in the active site pocket. In addition, they contain both a carboxylate and an acetamide group, bound to the central ring structure, which allow them to interact with five arginines, organized in a triad (Arg371, Arg118, Arg292) and a pair (Arg151, Arg152). These interactions are very strong and act as two anchors that fix the compounds in the active site. The inhibitory activity of the compounds is improved if they have hydrophobic groups pointing toward a hydrophobic region of the active site, where Ile222 is located, and when they have amine or guanidine groups pointing toward three glutamates (Glu277, Glu276, Glu227). The studies performed here lay the foundations for the rational design of new and more efficient drugs to fight the influenza virus.
Agility in Disaster Relief: A Social Construction Approach
Authors: Nelan Mary M. , Wachtendorf Tricia , Penta Samantha
Published: February 2018

The convergence of materiel donations following disaster events is well documented in the literature. This influx of goods is often dubbed a “second disaster” with non‐priority and unnecessary goods causing transportation and storage challenges to the community of survivors. Interviews were conducted following Hurricane Sandy in 2013 and two tornadoes outside of Oklahoma City in May 2013. Findings illustrate conflicting views about how to best achieve agility in disaster donation supply chains, although there was general agreement among interviewees that agility was desirable. From a broader perspective, the findings reveal that individuals involved in the supply chain differentially assign value in the donations process, including if they value donor needs over survivor needs, and hold different views on whether or not cash or goods are of greater value to the donors and survivors. Agility—the timing, flexibility, and reaction time in the supply chain—was viewed as necessary to a healthy supply chain; however, there was not a universal understanding of how to achieve an agile supply chain. This finding is consequential if relief operations hope to ultimately enhance agility in this process.
Ru/ZrO2 Catalysts for Transfer Hydrogenation of Levulinic Acid with Formic Acid/Formate Mixtures: Importance of Support Stability
Authors: Gao Yanxiu , Zhang Hongwei , Han Aijuan , Wang Jie , Tan Hui‐Ru , Tok Eng‐Soon , Jaenicke Stephan , Chuah Gaik‐Khuan
Published: February 2018

The transfer hydrogenation of levulinic acid to γ‐valerolactone using an equimolar mixture of formate/formic acid in water was investigated using Ru/ZrO2 catalysts. Ru/ZrO2 with < 3 wt. % loading were more active than those with higher loadings. The stability of the catalysts is of concern as the reaction occurs under acidic and hydrothermal conditions. To minimize metal leaching, the Ru/ZrO2 catalysts were prepared by a sol‐gel process to entrap the ruthenium nanoparticles within the support. Despite insignificant leaching of Ru, the used catalyst was deactivated after the first run. No agglomeration of Ru particles could be observed by TEM and XRD. However, the zirconia support had transformed from a predominantly tetragonal crystal phase to the monoclinic form. X‐ray photoelectron spectroscopy revealed a decrease in the surface Ru/Zr ratio. Doping with 0.1 wt. % SiO2 successfully stabilized the tetragonal phase of zirconia and the recycled catalyst maintained its high activity in reuse.
A Green and Versatile Route to Highly Functionalized Benzofuran Derivatives Using Biomimetic Oxygenation
Authors: Rebelo Susana L. H. , Pires Sónia M. G. , Simões Mário M. Q. , Medforth Craig J. , Cavaleiro José A. S. , Neves M. Graça P. M. S.
Published: February 2018

One‐pot green reactions useful for the synthesis of novel and potentially biologically active compounds have been developed using metaloporphyrin catalyzed oxidations of benzofurans. Minor variations of the reaction parameters allow direction of the reactivity (furan versus benzene ring) and the production of multifunctional 2,3‐dihydrobenzofurans, salicyl derivatives or an unusual dimerization product. These studies suggest pathways for the metabolic oxidation and activation of pharmaceuticals and other molecules containing the benzofuran core.
A Metal‐Free Oxidative Carboannulation Approach towards Synthesis of 2,3‐Diarylindenones and Its Regioisomers
Authors: Banerji Biswadip , Majumder Leena , Adhikary Saswati
Published: February 2018

A metal free, PIDA (Iodosobenzene diacetate) mediated radical oxidative annulation of aromatic aldehydes with 1,2‐diphenylethyne was developed, resulting an array of 2,3‐diaryl indenones in moderate to good yields. This methodology requires no preactivation of the aldehyde groups and involves activation of the C(sp)‐C(sp) bond of the internal alkyne by in situ generated acyl radical under metal free condition. This procedure is applicable to a large variety of functionalized substrates specially heterocyclic aldehydes and ortho hydroxyl aromatic aldehydes to give 2,3‐diaryl indenones. Interestingly, meta substituted aromatic aldehyde provided two regioisomers in 1:1 ratio when they were subjected to the experimental condition. These two regioisomers were isolated by column chromatography and their colour, spectral data and crystal structures were investigated.
A Ligand‐Based Approach to the Discovery of Lead‐Like Potassium Channel KV1.3 Inhibitors
Authors: Pereira Gilberto , Szwarc Beatriz , Mondragão Miguel A. , Lima Pedro A. , Pereira Florbela
Published: February 2018

Voltage‐gated ion channels are key molecular targets for autoimmune diseases such as multiple sclerosis, rheumatoid arthritis and psoriasis. In silico models, using 340 molecules whose IC50 towards Kv1.3 was determined by reported assays, were developed through exploration of four machine learning (ML) techniques. ML techniques explored included Random Forest, Support Vector Machine, Multilayer Perceptron, and K‐Nearest Neighbors. Two QSAR classification approaches were developed. In the first approach, the compounds were classified into either moderate‐active‐to‐very‐active or inactive‐to‐moderate‐active categories. Only the compounds predicted to be moderate‐active‐to‐very‐active in the first classification model were submitted to the second model, a classification model that predicted two more categories, very‐active and not‐very‐active. The performances of the models were successfully evaluated by internal validation and external test set validation, with an overall predictability (Q) of 0.83 and 0.69 for the test set in the first and second approaches of the best models, respectively. The best models for the two approaches were employed for the virtual screening of KV1.3 inhibitors from ZINC natural products and approved drugs databases. A list of the most promising lead‐like KV1.3 inhibitors was proposed, from which an approved drug and a natural product were experimentally evaluated with whole‐cell voltage‐clamp assays at 1000 nM.
A Practical and Efficient Stereoselective Synthesis of (S)‐Rivastigmine and (R)‐Rivastigmine
Authors: Hua Yong‐Gang , Han Lan‐Ping , Yang Qian‐Qian , Wang Mei‐Jing , Zhang En , Liu Hong‐Min
Published: February 2018

A stereoselective synthesis of (S)‐rivastigmine and (R)‐rivastigmine was developed. The key steps were stereoselective chlorination of a chiral secondary benzylic alcohol intermediate and amination of the corresponding chloride. Based on this method, both stereoisomers of rivastigmine were obtained stereoselectively in high yields.
Thermal Transport in Phosphorene
Authors: Qin Guangzhao , Hu Ming
Published: February 2018

Phosphorene, a novel elemental 2D semiconductor, possesses fascinating chemical and physical properties which are distinctively different from other 2D materials. The rapidly growing applications of phosphorene in nano/optoelectronics and thermoelectrics call for comprehensive studies of thermal transport properties. In this Review, based on the theoretical and experimental progresses, the thermal transport properties of single‐layer phosphorene, multilayer phosphorene (nanofilms), and bulk black phosphorus are summarized to give a general view of the overall thermal conductivity trend from single‐layer to bulk form. The mechanism underlying the discrepancy in the reported thermal conductivity of phosphorene is discussed by reviewing the effect of different functionals and cutoff distances on the thermal transport evaluations. This Review then provides fundamental insight into the thermal transport in phosphorene by reviewing the role of resonant bonding in driving giant phonon anharmonicity and long‐range interactions. In addition, the extrinsic thermal conductivity of phosphorene is reviewed by discussing the effects of strain and substrate, together with phosphorene based heterostructures and nanoribbons. This Review summarizes the progress of thermal transport in phosphorene from both theoretical calculations and experimental measurements, which would be of significance to the design and development of efficient phosphorene based nanoelectronics.
Graphene Scroll‐Coated α‐MnO2 Nanowires as High‐Performance Cathode Materials for Aqueous Zn‐Ion Battery
Authors: Wu Buke , Zhang Guobin , Yan Mengyu , Xiong Tengfei , He Pan , He Liang , Xu Xu , Mai Liqiang
Published: February 2018

The development of manganese dioxide as the cathode for aqueous Zn‐ion battery (ZIB) is limited by the rapid capacity fading and material dissolution. Here, a highly reversible aqueous ZIB using graphene scroll‐coated α‐MnO2 as the cathode is proposed. The graphene scroll is uniformly coated on the MnO2 nanowire with an average width of 5 nm, which increases the electrical conductivity of the MnO2 nanowire and relieves the dissolution of the cathode material during cycling. An energy density of 406.6 Wh kg−1 (382.2 mA h g−1) at 0.3 A g−1 can be reached, which is the highest specific energy value among all the cathode materials for aqueous Zn‐ion battery so far, and good long‐term cycling stability with 94% capacity retention after 3000 cycles at 3 A g−1 are achieved. Meanwhile, a two‐step intercalation mechanism that Zn ions first insert into the layers and then the tunnels of MnO2 framework is proved by in situ X‐ray diffraction, galvanostatic intermittent titration technique, and X‐ray photoelectron spectroscopy characterizations. The graphene scroll‐coated metallic oxide strategy can also bring intensive interests for other energy storage systems.
Modulating the Symmetry of Benzodithiophene by Molecular Tailoring for the Application in Naphthalene Diimide‐Based N‐Type Photovoltaic Polymers
Authors: Yang Jing , Chen Fan , Xiao Bo , Sun Su , Sun Xiangnan , Tajima Keisuke , Tang Ailing , Zhou Erjun
Published: February 2018

To investigate the effect of symmetry of copolymerized unit on the properties of naphthalene diimide (NDI)‐based photovoltaic polymers, three n‐type semiconductor polymers, PNDI‐BDT, PNDI‐T‐BTh, and PNDI‐T‐P‐T are synthesized by copolymerizing NDI with benzodithiophene (BDT), thienylene‐benzothiophene (T‐BTh), and thienylene‐phenylene‐thienylene (T‐P‐T) units, respectively. The latter two building blocks could be regarded as the derivatives from BDT by molecular tailoring and only T‐BTh is an asymmetric segment. The light absorption, carrier mobility, film morphology, crystallinity, and photovoltaic properties of three PNDIs are systematically characterized and compared. Although PNDI‐T‐BTh adopts a face‐on molecular orientation, it shows a high field‐effect electron mobility (μe) of 1.06 × 10−2 cm2 V−1 s−1, which is comparable to the μe of PNDI‐BDT (1.37 × 10−2 cm2 V−1 s−1) with edge‐on molecular orientation. The photovoltaic devices with PNDI‐T‐BTh as the acceptor show the highest power conversion efficiency (PCE) of 5.99% with VOC of 0.87 V, JSC of 10.28 mA cm−2, and FF of 0.67, while PNDI‐BDT and PNDI‐T‐P‐T containing the symmetric copolymerized units give lower PCE of 2.06 and 4.12%, respectively. The higher PCE with PNDI‐T‐BTh could be attributed to the favorable face‐on molecular orientation, fiber‐like blend film morphology and relatively balanced hole and electron mobilities. Our results indicate that the introduction of the asymmetric unit could efficiently improve the photovoltaic performance, which provides a feasible and effective strategy to design novel NDI‐based and even other type rylene diimide‐based photovoltaic polymers.
Exploring architecture blueprints for prioritizing critical code anomalies: Experiences and tool support
Authors: Guimarães E. , Vidal S. , Garcia A. , Diaz Pace J. A. , Marcos C.
Published: February 2018

The manifestation of code anomalies in software systems often indicates symptoms of architecture degradation. Several approaches have been proposed to detect such anomalies in the source code. However, most of them fail to assist developers in prioritizing anomalies harmful to the software architecture of a system. This article presents an investigation on how developers, when supported by architecture blueprints, are able to prioritize architecturally relevant code anomalies. First, we performed a controlled experiment where participants explored both blueprints and source code to reveal architecturally relevant code anomalies. Although the use of blueprints has the potential to improve code anomaly prioritization, the participants often made several mistakes. We found these mistakes might occur because developers miss relationships between implementation and blueprint elements when they prioritize anomalies in an ad hoc manner. Furthermore, the time spent on the prioritization process was considerably high. Aiming to improve the accuracy and effectiveness of the process, we provided means to automate the prioritization process. In particular, we explored 3 prioritization criteria, which establish different ways of relating the blueprint elements with code anomalies. These criteria were implemented in the JSpIRIT tool. The approach was evaluated in the context of 2 applications with satisfactory precision results.
Scenario‐oriented reverse engineering of complex railway system specifications
Authors: Issad Melissa , Kloul Leila , Rauzy Antoine
Published: February 2018

In this article, we present a scenario‐oriented modeling methodology dedicated to the analysis and the formalization of complex system specifications. The methodology relies on the SCOLA semiformal notation to describe scenarios and on a formal execution model described in the AltaRica 3.0 modeling language. We designed this methodology because we had to review thousands of pages of natural language specifications of a railway system in view of their validation with respect to safety constraints. We needed therefore some means to understand what the system was supposed to be and to do as well as to support a dialog with experts. This article aims at introducing the methodology and the modeling formalism that supports it as well as at discussing its application to the railway systems.
A new network intrusion detection algorithm: DA‐ROS‐ELM
Authors: Yu Yi , Kang SongLin , Qiu He
Published: February 2018

In this paper, a novel dual adaptive regularized online sequential extreme learning machine (DA‐ROS‐ELM) is proposed to detect network intrusion. The ridge regression factor based on Tikhonov regularization is introduced to solve the over‐fitting and ill‐posed problems. According to the arrived data in each updating phase and all currently available data, dual adaptive mechanism is designed to respectively select the suitable updating mode of output weight β and regularized parameter C. The performance of our algorithm is assessed by NSL‐KDD dataset, and the results show that the DA‐ROS‐ELM can obtain faster training speed, higher accuracy, lower rate of false positive and false negative, and greater generalization performance than other network intrusion detection algorithms. Besides, the adaptive mechanism makes this algorithm can meet the real‐time requirement of the network intrusion system. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.