bluuebunny/crossref_metadata_2025 huggingface dataset:
Forming Covalent Crosslinks between Polymer‐Grafted Nanoparticles as a Route to Highly Filled and Mechanically Robust Nanocomposites
Authors: Kubiak Joshua M. , Macfarlane Robert J.
Published: August 2019

Filler aggregation in polymer matrix nanocomposites leads to inhomogeneity in particle distribution and deterioration of mechanical properties. The use of polymer‐grafted nanoparticles (PGNPs) with polymers directly attached to the particle surfaces precludes aggregation of the filler. However, solids composed of PGNPs are mechanically weak unless the grafted chains are long enough to form entanglements between particles, and requiring long grafts limits the achievable filler density of the nanocomposite. In this work, long, entangled grafts are replaced with short reactive polymers that form covalent crosslinks between particles. Crosslinkable PGNPs, referred to as XNPs, can be easily processed from solution and subsequently cured to yield a highly filled yet mechanically robust composite. In this specific instance, silica nanoparticles are grafted with poly(glycidyl methacrylate), cast into films, and crosslinked with multifunctional amines at elevated temperatures. Indentation and scratch experiments show significant enhancement of hardness, modulus, and scratch resistance compared to non‐crosslinked PGNPs and to crosslinked polymer films without nanoparticle reinforcement. Loadings of up to 57 wt% are achieved while yielding uniform films that deform locally in a predominantly elastic manner. XNPs therefore potentially allow for the formulation of robust nanocomposites with a high level of functionality imparted by the selected filler particles.
Facile and Versatile Functionalization of Two‐Dimensional Carbon Nitrides by Design: Magnetism/Multiferroicity, Valleytronics, and Photovoltaics
Authors: Li Lei , Wu Menghao , Zeng Xiao Cheng
Published: August 2019

Ab initio calculation evidence has shown that two‐dimensional (2D) carbon nitrides may enable “facile functionalization” when a domain of carbon nitride is wetted by a solution of metal halides with mobile cations/anions. During the wetting process, each cavity can be functionalized by a unit of metal halide. Compared with prevailing functionalization or doping strategies through either high‐temperature diffusion of source ions or ion implantation by using accelerators, such a room‐temperature “wet‐lab” functionalization approach is more facile and efficient. The wet‐lab functionalization not only can facilitate isolation of the 2D monolayer, but also, with applying different metal halides, enable various new and desirable properties for broad applications, e.g., 2D magnetism and 2D ferroelectricity with high piezoelectric coefficient. The latter can be implemented in spin‐independent valleytronics for non‐volatile electrical manipulations. Notably, tunable bandgaps, ranging from 1.0 to 2.5 eV, can be realized by controlling the metal‐halide functionalization density, while the separation of electrons/holes can be facilitated by the ferroelectric polarizations and heterostructure band alignments. Moreover, multifunctional domains like P/N doped or magnetic/ferroelectric domains can be selectively constructed through such solution‐processed functionalization with different halides, followed by seamless integration into a single sheet of carbon nitride, akin to the P/N channels in silicon wafers.
Quasi‐Single‐Crystalline ZnGa2O4Films via Solid Phase Epitaxy for Enhancing Deep‐Ultraviolet Photoresponse
Authors: Chen Po‐Wei , Huang Shiau‐Yuan , Yuan Shuo‐Huang , Chen Yi‐An , Hsiao Po‐Wen , Wuu Dong‐Sing
Published: August 2019

The complex‐oxide materials are multifunctional materials, which have wide applications to the semiconductor and microelectronic fields. The ZnGa2O4having a wide bandgap of 5.1 eV is one of the promising materials for deep‐ultraviolet photodetector (PD) applications. The ZnGa2O4films are deposited by using conventional radio‐frequency magnetron sputtering which is extensively employed in the industry. However, the as‐deposited ZnGa2O4films show the disordered nanocrystalline structure, resulting in the relatively poor performance. Since the Zn atoms can diffuse out of the film structure during the annealing, the ZnGa2O4material is difficult to get the single‐crystalline structure by using the sputtering method. Here, the solid‐phase epitaxy method is used for crystallizing the ZnGa2O4structure via rapid thermal annealing process. The disordered crystal grains as incubated seeds are obtained in the as‐deposited ZnGa2O4film at the substrate temperature of 400 °C. Further annealing under the temperature of 700 °C in 1 min, the ZnGa2O4film structure approaches the quasi‐single‐crystalline ZnGa2O4structure, which is evidenced by checking the transmission electron microscopy. The responsivity of annealed ZnGa2O4PDs can reach 2.53 A W−1(at 240 nm and 5 V), which shows a relative enhancement of 256% compared with the as‐deposited ZnGa2O4PDs.
Mechanisms and Dynamics of Mineral Dissolution: A New Kinetic Monte Carlo Model
Authors: Martin Pablo , Manzano Hegoi , Dolado Jorge S.
Published: August 2019

Mineral dissolution is a fundamental process in geochemistry and materials science. It is controlled by the complex interplay of atomic level mechanisms like adatoms and terraces removal, pit opening, and spontaneous vacancy creation that can be gradually activated at different energies. Though the development of a comprehensive atomistic model is key to go deeper into the understanding of this phenomenon, existing models have failed to reproduce the abrupt dependence of the dissolution rate with the Gibbs free energy (). Herein, a new atomistic kinetic Monte Carlo (KMC) model is presented, which, invoking the microscopic reversibility of chemical reactions, captures the experimentally observed sigmoid dependence of the dissolution rate and provides new insights on the concomitant dissolution mechanisms. As a salient result, the model predicts the possible existence of unreported close‐to‐equilibrium dissolution modes where spontaneous vacancies creation and pit opening can occur before adatom and terrace removal.
Titanium(IV) Inclusion as a Versatile Route to Photoactivity in Metal–Organic Frameworks
Authors: Mancuso Jenna L. , Hendon Christopher H.
Published: August 2019

Titanium‐containing metal–organic frameworks (MOFs) are known to perform light‐promoted chemical transformations. Formation of these frameworks, accessed either natively or via transmetallation, can instill beneficial photocatalytic properties in previously photo‐inert scaffolds. Band edge diagrams coupled with their density of states illustrate the persistent nature of the accessible titanium d‐states at the conduction band edge, independent of linker identity. In essentially all of these Ti‐containing frameworks, the valence band edge localizes on the organic component, permitting facile modulation of the band gap. In sum, the spatial separation of photogenerated excitons will be observed in both the native and titanium(IV)‐substituted MOFs, and this exciton pair is useful in photocatalysis.
Self‐Assembled Flexible and Integratable 3D Microtubular Asymmetric Supercapacitors
Authors: Li Fei , Wang Jinhui , Liu Lixiang , Qu Jiang , Li Yang , Bandari Vineeth Kumar , Karnaushenko Daniil , Becker Christian , Faghih Maryam , Kang Tong , Baunack Stefan , Zhu Minshen , Zhu Feng , Schmidt Oliver G.
Published: August 2019

The rapid development of microelectronics has equally rapidly increased the demand for miniaturized energy storage devices. On‐chip microsupercapacitors (MSCs), as promising power candidates, possess great potential to complement or replace electrolytic capacitors and microbatteries in various applications. However, the areal capacities and energy densities of the planar MSCs are commonly limited by the low voltage window, the thin layer of the electrode materials and complex fabrication processes. Here, a new‐type three‐dimensional (3D) tubular asymmetric MSC with small footprint area, high potential window, ultrahigh areal energy density, and long‐term cycling stability is fabricated with shapeable materials and photolithographic technologies, which are compatible with modern microelectronic fabrication procedures widely used in industry. Benefiting from the novel architecture, the 3D asymmetric MSC displays an ultrahigh areal capacitance of 88.6 mF cm−2 and areal energy density of 28.69 mW h cm−2, superior to most reported interdigitated MSCs. Furthermore, the 3D tubular MSCs demonstrate remarkable cycling stability and the capacitance retention is up to 91.8% over 12 000 cycles. It is believed that the efficient fabrication methodology can be used to construct various integratable microscale tubular energy storage devices with small footprint area and high performance for miniaturized electronics.
Time‐Tailoring van der Waals Heterostructures for Human Memory System Programming
Authors: Chen Huawei , Liu Chunsen , Wu Zuheng , He Yongli , Wang Zhen , Zhang Heng , Wan Qing , Hu Weida , Zhang David Wei , Liu Ming , Liu Qi , Zhou Peng
Published: August 2019

The human memory system plays an indispensable role in oblivion, learning, and memorization. Implementing a memory system within electronic devices contributes an important step toward constructing a neuromorphic system that emulates advanced mental functions of the human brain. Given the complex time‐tailoring requirement, integrating a human memory system into one system is a great challenge. Here, one van der Waals heterostructure with flexible time‐tailoring ability is demonstrated, which can meet the high requirement of human memory system programming. By stacking volatile and nonvolatile function layers, all basic memory types, including sensory memory, short‐term and long‐term memory are integrated into the device and the transition between these memory types are flexible. Moreover, decision‐making action and in situ result storage are also demonstrated. It is anticipated that the demonstrated time‐tailoring system will support the model of a human memory system.
In Situ Nanostructural Analysis of Volatile Threshold Switching and Non‐Volatile Bipolar Resistive Switching in Mixed‐Phased a‐VOx Asymmetric Crossbars
Authors: Nirantar Shruti , Mayes Edwin , Rahman Md. Ataur , Ahmed Taimur , Taha Mohammad , Bhaskaran Madhu , Walia Sumeet , Sriram Sharath
Published: August 2019

Vanadium oxide is a multi‐functional, phase‐change material that shows both apolar threshold switching (TS) and bipolar resistive switching (BRS) in a mixed‐phase film. However, the origins of its multifunctional behavior and respective switching mechanisms are still unproven. Here, asymmetric cross‐point devices are introduced based on an amorphous mixed‐phase vanadium oxide film. The devices show condition‐dependent volatile TS post‐electroforming as well as electroforming‐free non‐volatile BRS. An interesting two‐step volatile TS is also observed post‐electroforming in few devices. This work proves that the volatile TS is due to the insulator‐to‐metal (IMT) transition in local crystal islands of vanadium dioxide based on the electrical in situ transmission electron microscopy and highlights origins of two‐step volatile TS based on nanostructural changes. This insight will not only pave a path to adopt vanadium oxide in crossbar arrays and control its functionality with electrical conditions, but also highlights the process of crystallizing vanadium dioxide just with electrical bias without any high temperature annealing. Stimuli‐triggered or condition‐dependent switching control of memory elements will enable programmable logic and neuromorphic circuits incorporating vanadium oxide.
Flexible and High‐Loading Lithium–Sulfur Batteries Enabled by Integrated Three‐In‐One Fibrous Membranes
Authors: Wang Jianan , Yang Guorui , Chen Jie , Liu Yunpeng , Wang Yuankun , Lao Cheng‐Yen , Xi Kai , Yang Duowen , Harris Christopher J. , Yan Wei , Ding Shujiang , Kumar Ramachandran Vasant
Published: August 2019

Lithium–sulfur batteries are appealing as high‐energy storage systems and hold great application prospects in wearable and portable electronics. However, severe shuttle effects, low sulfur conductivity, and especially poor electrode mechanical flexibility restrict sulfur utilization and loading for practical applications. Herein, high‐flux, flexible, electrospun fibrous membranes are developed, which succeed in integrating three functional units (cathode, interlayer, and separator) into an efficient composite. This structure helps to eliminate negative interface effects, and effectively drives synergistic boosts to polysulfide confinement, electron transfer, and lithium‐ion diffusion. It delivers a high initial capacity of 1501 mA h g−1 and a discharge capacity of 933 mA h g−1 after 400 cycles, with slow capacity attenuation (0.069% per cycle). Even under high sulfur loading (13.2 mg cm−2, electrolyte/sulfur ratio = 6 mL g−1) or in an alternative folded state, this three‐in‐one membrane still exhibits high areal capacity (11.4 mA h cm−2) and exceptional application performance (powering an array of over 30 light‐emitting diodes (LEDs)), highlighting its huge potential in high‐energy flexible devices.
Spontaneous Interface Ion Exchange: Passivating Surface Defects of Perovskite Solar Cells with Enhanced Photovoltage
Authors: Li Zhipeng , Wang Li , Liu Ranran , Fan Yingping , Meng Hongguang , Shao Zhipeng , Cui Guanglei , Pang Shuping
Published: August 2019

Interface engineering is of great concern in photovoltaic devices. For the solution‐processed perovskite solar cells, the modification of the bottom surface of the perovskite layer is a challenge due to solvent incompatibility. Herein, a Cl‐containing tin‐based electron transport layer; SnOx‐Cl, is designed to realize an in situ, spontaneous ion‐exchange reaction at the interface of SnOx‐Cl/MAPbI3. The interfacial ion rearrangement not only effectively passivates the physical contact defects, but, at the same time, the diffusion of Cl ions in the perovskite film also causes longitudinal grain growth and further reduces the grain boundary density. As a result, an efficiency of 20.32% is achieved with an extremely high open‐circuit voltage of 1.19 V. This versatile design of the underlying carrier transport layer provides a new way to improve the performance of perovskite solar cells and other optoelectronic devices.
The role of early care and education in addressing early childhood trauma
Authors: Bartlett Jessica Dym , Smith Sheila
Published: August 2019

Young children's experience of trauma is associated with a wide range of adverse events and circumstances, including abuse and neglect, domestic violence, loss of a parent, and community violence. Policymakers and practitioners are increasingly aware that trauma during the first few years of life is especially widespread, and there is growing interest in new ways to support these young children and their families. Many young children who experience trauma attend early care and education (ECE) programs, and these settings offer important opportunities to promote their well‐being. This paper examines strategies currently being implemented in ECE to address early childhood trauma. The paper first examines research on how trauma affects young children's development, ECE environments, and society. We then describe the unique needs of young, traumatized children and features of trauma‐informed care that can address their needs, along with emerging interventions and supports that can be incorporated into or linked with ECE settings as part of a trauma‐informed approach. We conclude with a discussion of future directions for ECE and trauma research, policy, and practice, bearing in mind both the promise of new approaches and a limited evidence base to date.
Narrative Psychiatry and Family Therapy: Promoting Resilience and Collaboration with Persons with Intense Mental and Emotional Experiences at Risk of Causing Violence
Authors: Hamkins SuEllen
Published: August 2019

Narrative psychiatry identifies meaning‐making as a primal force in our lives and guides family therapists and psychiatrists in cultivating narratives of resilience that support safety and wellbeing when working with families in which a member is dealing with intense mental and emotional experiences and may be at risk of causing violence. These contexts are fraught with implications about power, control, identity, and ethical responsibilities of care for those consulting with us and for the wider community. Offering benefits distinct from pathology‐focused psychiatric practice, narrative psychiatry applies the practices of narrative therapy in psychiatric contexts, focusing on strengths and meaning and honouring how values, intentions, and commitments compel and constrain our actions. Illustrated by case conversations, this paper describes five key practices of narrative psychiatry, including emotional attunement, understanding the person without the problem, externalising problems, creating narratives of resilience, and collaborative treatment planning. It shows how narrative psychiatry facilitates risk reduction through helping a person identify values and narratives that support non‐violence and strengthening abilities, relationships and resources that help them stay true to this commitment. Practical ways that family therapists and psychiatrists can use conversations about resources, including medicines, to deconstruct damaging discourses and generate narratives of resilience are described. Discussion is offered about how narrative psychiatry can support clinicians in ethically negotiating clinical dilemmas in which the preferences of the person or family are in conflict with the clinician's ethical and legal duty to protect life.
Related physicochemical, rheological, and dielectric properties of nanocomposites of superparamagnetic iron oxide nanoparticles with polyethyleneglycol
Authors: Javanbakht Taraneh , Laurent Sophie , Stanicki Dimitri , David Eric
Published: August 2019

In this study, we present the physicochemical, rheological, and dielectric properties of the superparamagnetic iron oxide nanoparticles (SPIONs) coated with polyethyleneglycol (PEG). It was observed that the increase of the concentration of PEG prohibited the sedimentation of nanoparticles, which increased the colloidal stability of nanocomposites. The surface study of the polymer and the nanocomposites using TOF‐SIMS showed that the samples did not have the same surface properties. The analysis of the intensity ratios of the FeO+/Fe+and OH−/O−peaks of the nanocomposites of bare, positively, and negatively charged SPIONs with PEG revealed that no reduction occurred for these nanoparticles when coated with PEG, whereas the iron atoms on the surface of PEG negatively charged SPIONs were less oxidized than those on the surface of PEG‐bare SPIONs, and the iron atoms on the surface of PEG positively charged SPIONs were more oxidized than the second ones. The rheological study of the polymer and the nanocomposites revealed that the presence of SPIONs did not change the rheological behavior of PEG. The analysis of the dielectric properties of PEG and its composites with SPIONs showed that when SPIONs particles (bare and positively charged) were included in PEG, low frequency dispersion (LFD) was strongly enhanced, that the iron oxide nanoparticles reduced the impedance of PEG in the nanocomposites and that the difference in their surface charge affected their impedance. Taken together, these results suggest that the nanocomposites of PEG with SPIONs have appropriate properties for fluid modification and applications in the nanotechnology and photovoltaic devices. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2020,137, 48280.
Eutectic Molecular Liquids Based on Hydrogen Bonding and π–π Interaction for Exfoliating Two‐dimensional Materials and Recycling Polymers
Authors: Yu Dongkun , Mou Hongyu , Zhao Xinhui , Wang Yaqing , Mu Tiancheng
Published: August 2019

Eutectic molecular liquids (EMLs) based on hydrogen‐bonding interaction and π–π stacking were prepared. We found that the thermodynamic properties like initial decomposition temperature and glass transition temperature of EMLs are mainly dominated by the hydrogen bond donor, which is beneficial for designing and preparing new EMLs. These new liquid systems could be applied in the field of environmental and material science.
A Gas Diffusion Layer Impregnated with Mn3O4‐Decorated N‐Doped Carbon Nanotubes for the Oxygen Reduction Reaction in Zinc‐Air Batteries
Authors: Aasen Drew , Clark Michael , Ivey Douglas G.
Published: August 2019

Mn3O4‐decorated N‐CNTs are synthesized and impregnated into porous carbon paper (gas diffusion layer or GDL) to form a composite catalyst‐GDL material in a simple and novel one‐pot process. The impregnated electrode features high active surface area, improved discharge performance, and reduced vulnerability to flooding when compared with other electrode preparation techniques for similar catalysts. Electrochemical and battery testing show catalytic activity and a maximum discharge potential superior to other CNT supported Mn3O4 catalysts, and comparable to commercially used Pt−Ru (1.21 V at 20 mA cm−2). The composite is cycled at 10 mA cm−2 and 20 mA cm−2 as a bifunctional catalyst and as an oxygen reduction reaction (ORR) exclusive catalyst, respectively. Discharge performance is stable over 200 cycles at 20 mA cm−2 when used exclusively for ORR with a discharge‐charge efficiency superior to Pt−Ru when coupled with electrodeposited Co−Fe as the OER catalyst (efficiency of 59 % after cycling).
Overcoming lignocellulose‐derived microbial inhibitors: advancing the Saccharomyces cerevisiae resistance toolbox
Authors: Brandt Bianca A. , Jansen Trudy , Görgens Johann F. , van Zyl Willem H.
Published: August 2019

Lignocellulose‐derived biofuels present an attractive carbon‐neutral alternative to fossil fuels amidst growing global energy and climate concerns. Bioethanol in particular, has been shown to be a viable additive to and / or replacement for petroleum in countries such as Brazil. The bioconversion of lignocellulose biomass to bioethanol is a developing technology with the yeast Saccharomyces cerevisiae playing a pivotal role in the fermentation‐based processes. This yeast however, is challenged to ferment under harsh conditions, specifically, during exposure to lignocellulose‐derived microbial inhibitors that are formed during pretreatment processes. This detrimentally affects biocatalyst performance, ultimately decreasing ethanol productivity and yield. To this end, S. cerevisiae strains are in development to increase the yeast microbial inhibitor resistance towards cost‐effective cellulosic bioethanol production. This review discusses the current status of inhibitor resistance in S. cerevisiae strains and perspectives on the future of multi‐tolerant phenotypes with a specific focus on existing and emerging strain development strategies designed to improve resistance phenotypes. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.
Further Results in Estimating the Classification Error in Discriminance Analysis
Authors: Wernecke K.‐D. , Kalb G.
Published: August 2019

Basing on the approach by McLachlan (1977) a procedure for the conditional and common error estimation of the classification error in discriminance analysis is described for k ≧ 2 classes.

As a rapid procedure for large sample sizes and feature numbers, a modification of the resubstitution method is proposed being favourable with respect to computing time.

Both methods provide useful estimations for the probability of misclassification.

In calculating the weighting function w, deviations from preconditions known from the MANOVA such as the skewness, the truncation or the inequality of the covariance matrices, hardly play any role; it appears that only a variation of the sample sizes of the classes substantially influences the weighting functions.

The error rates of the tested error estimation methods likewise in effect depend on the sample sizes of the classes. Violations of the mentioned preconditions in the form described above result in different variations of the error estimates, depending on these sample sizes.

A comparison between error estimation and allocation relative to a simulated population demonstrates the goodness of the used error estimation procedures.
Sample Variances for Several MINQ‐Estimators in the One‐way Classification
Authors: Sánchez J.
Published: August 2019

A generalization of Ahrens' (1965) formulas for sample variances is done, considering the case of MINQ‐Estimators which may be biased. The formulas are generally valid, but are restricted for the sake of simplicity to those of the one‐way classification. Some MINQ‐Estimators are considered and their sample variances calculated.
A Note on Contingency Tables with one Structural Zero
Authors: Victor N.
Published: August 2019

Based on a definition of Quasi‐Independence, which is equivalent to the usual one but easier to interpret, rules for the calculation of ML‐estimates in Contingency Tables with one structural zero are given. These rules are much simpler than the usual ones; even explicit solutions exist up to five dimensions. Possible extensions for other hypotheses and for more than one structural zero are suggested.
Computational Algorithm for Least Squares Estimation of Parameters in Compartmental Analysis
Authors: Shah A. C.
Published: August 2019

This paper presents a new computational algorithm for the estimation of the parameters in multi‐compartmental processes. By assuming the initial state of compartmental process known, the Newton‐Raphson iterative process is vised to obtain weighted least squares estimates. The estimation procedure considers broad class of structural properties (defined in the sequel) of compartmental models, such as open‐closed processes, cyclic pathways, conservative processes, connectivity etc. A computer program, which includes these structural properties is supplied. Two examples of simulated processes illustrate the estimation procedure.
Simple Test Statistics for a Fixed Number of Matched Samples with Ordinal Outcome Variables
Authors: Nurminen M. , Järvinen E. , Mutanen P.
Published: August 2019

In a preceding paper, we (Nurminen et al. 1981) advocated the use of the sole referent series as the basis of estimating moments in the construction of test statistics for comparative studies. Three simple test statistics, two metric approaches and one procedure based on ranks, incorporating this principle are introduced for small matched samples with ordinal outcome variables. Associated methods for computing an “exact” probability value are derived. The techniques are illustrated by real data from a study in the field of occupational health epidemiology.
Modelling the Evolution of the Number of Genera in Animal Groups (Yule's Problem Revisited)
Authors: Stoyan D. , Stoyan H. , Fiksel Th.
Published: August 2019

The evolution of the number of genera in animal groups such as families, orders etc. is studied using paleontological data. The aim is to estimate birth‐rates and mean existence‐times of genera, which are here parameters of a birth‐and‐death process model. Two examples illustrate the method.
Insensitivity of Minimax Linear Estimators
Authors: Toutenburg H.
Published: August 2019

If one has prior information on the unknown parameter vectorβof a linear model such thatßmay be assumed to lie in a concentration ellipsoid, then the resulting minimax linear estimator (MILE) is of ridge type and has smaller quadratic risk than the GLSE. This holds whenever the prior information is a true one. The relation between MILE and GLSE is investigated under incorrect specified prior regions. The MILE is said to be robust against misspecification of the prior region, if its risk stays smaller than the risk of the GLSE.
Antler and Body Weight Allometry in Red Deer: A Comparison of Statistical Estimators
Authors: Schröder J.
Published: August 2019

In allometric expressions, both variables are measured with error. Such structural relationships require specific statistical techniques for precise and valid estimation of equation parameters. The relative growth pattern for antler weight and body weight was examined for 1700 red deer (Cervus elaphusL.) stags from the Harz mountain district in West Germany. Coefficients for the allometric equation were determined using several statistical estimation procedures and the results were compared and evaluated. There is evidence that the magnitude of the exponent in the allometric expression increases with the onset of sexual maturity.
Modeling alginate encapsulation system for biological hydrogen production
Authors: Zhu Kuang , Arnold William A. , Novak Paige J.
Published: August 2019

Wastewater treatment using encapsulated biomass is a promising approach for high‐rate resource recovery. Encapsulation matrices can be customized to achieve desired biomass retention and mass transport performance. This, in turn, facilitates treatment of different waste streams. In this study, a model was developed to describe calcium‐alginate beads encapsulating hydrogen‐producing biomass, with the goal of enabling appropriate a priori customization of the system. The model was based on a classic diffusion‐reaction model, but also included the growth of encapsulated biomass and product inhibition. Experimental data were used to verify the model, which accurately described the effect of hydraulic retention time, bead size, and feed concentration on resource (hydrogen) recovery from brewery wastewater. Sensitivity analyses revealed that the hydrogen production rate was insensitive to substrate diffusivity and bead size, but sensitive to the substrate partition coefficient, initial encapsulated biomass concentration, and the total volume of beads in the reactor, demonstrating that this system was growth‐limited rather than diffusion‐limited under the tested conditions. Because the model quantifies the relationship between the hydrogen production rate and various input and operating parameters, it should be possible to extend the model to determine the most cost‐effective system for optimal performance with a given waste stream.
Reciprocal associations between job strain and depression: A 2‐year follow‐up study from the Survey of Health, Ageing and Retirement in Europe
Authors: Qiao Ya‐Mei , Lu Ya‐Ke , Yan Zhen , Yao Wu , Pei Jin‐Jing , Wang Hui‐Xin
Published: August 2019

Background

A growing number of people suffered from depression. This study examined the depression prevalence in workers across 10 European countries plus Israel and the reciprocal associations between job strain and depression.

Methods

The study population consisted of 7,879 workers aged 50–63 years at baseline (2004) from the Survey of Health, Ageing, and Retirement in Europe (SHARE). Job demands (physical or psychosocial) and job control variables were derived from the Job Content Questionnaire (JCQ). Two 4‐category job strains (physical and psychosocial) were obtained based on the cross‐tabulation of these dichotomized demands and control variables. There were 4,284 depression‐free, 3,259 high physical strain‐free and 3,195 high psychosocial strain‐free participants at baseline who were followed up for 2 years to detect incident depression, high physical job strain, or high psychosocial strain, respectively. The reciprocal associations between job strain and depression were analyzed by multivariate logistic regression and multivariate multilevel logistic regression adjusting for potential confounders.

Results

The prevalence of depression varied from the lowest 12.5% in Germany to the highest 27.2% in France. Compared to individuals with low strain, a significantly higher risk of depression were found in individuals with high physical strain (OR = 1.39) and high psychosocial strain (OR = 1.55), after adjusting for potential confounders. Depression at baseline was not significantly associated with subsequent high job strain. Similar results were observed from multilevel models that took into consideration of the potential country‐level influences.

Conclusions

The prevalence of depression varies across countries in Europe. Avoiding high job strain may be an effective preventive strategy to prevent depression epidemic.
Chemosensitizing Effect of Cernumidine Extracted from Solanum cernuum on Bladder Cancer Cells in Vitro
Authors: Miranda Mariza A. , Mondal Arindam , Sachdeva Mandip , Cabral Hamilton , Neto Youssef A. A. H. , Khan Ikhlas , Groppo Milton , McChesney James D. , Bastos Jairo K.
Published: August 2019

Cernumidine (CER) is a guanidinic alkaloid isolated from Solanum cernuum leaves. In this work, we investigated the cytotoxicity, chemosensitizing effect of cernumidine to cisplatin (cDDP) and the possible mechanism of action of the combination on bladder cancer cells. Cernumidine showed cytotoxicity and could sensitize bladder cancer cells to cisplatin. The combination of CER+cDDP inhibited cell migration on T24 cells. CER+cDDP down‐regulated MMP‐2/9 and p‐ERK1/2, while it increased EGFR activity corroborating the observed cell migration inhibition. Down‐regulation of Bcl‐2 and up‐regulation pro‐apoptotic Bax and further depletion of the mitochondrial membrane potential (ΔΨm) indicates that mitochondria play a central role in the combination treatment inducing the mitochondrial signaling pathway of apoptosis in T24 cells. Our data showed that the alkaloid cernumidine is worthy of further studies as a chemosensitizing agent to be used in complementary chemotherapy.
Effects of mechanical vibration on cell morphology, proliferation, apoptosis, and cytokine expression/secretion in osteocyte‐like MLO‐Y4 cells exposed to high glucose
Authors: Sun Tao , Yan Zedong , Cai Jing , Shao Xi , Wang Dan , Ding Yuanjun , Feng Ying , Yang Jingyue , Luo Erping , Feng Xue , Jing Da
Published: August 2019

Diabetic patients exhibit significant bone deterioration. Our recent findings demonstrate that mechanical vibration is capable of resisting diabetic bone loss, whereas the relevant mechanism remains unclear. We herein examined the effects of mechanical vibration on the activities and functions of osteocytes (the most abundant and well‐recognized mechanosensitive cells in the bone) exposed to high glucose (HG). The osteocytic MLO‐Y4 cells were incubated with 50 mM HG for 24 h, and then stimulated with 1 h/day mechanical vibration (0.5 g, 45 Hz) for 3 days. We found that mechanical vibration significantly increased the proliferation and viability of MLO‐Y4 cells under the HG environment via the MTT, BrdU, and Cell Viability Analyzer assays. The apoptosis detection showed that HG‐induced apoptosis in MLO‐Y4 cells was inhibited by mechanical vibration. Moreover, increased cellular area, microfilament density, and anisotropy in HG‐incubated MLO‐Y4 cells were observed after mechanical vibration via the F‐actin fluorescence staining. The real‐time polymerase chain reaction and western blotting results demonstrated that mechanical vibration significantly upregulated the gene and protein expression of Wnt3a, β‐catenin, and osteoprotegerin (OPG) and decreased the sclerostin, DKK1, and receptor activator for nuclear factor‐κB ligand (RANKL) expression in osteocytes exposed to HG. The enzyme‐linked immunosorbent assay assays showed that mechanical vibration promoted the secretion of prostaglandin E2 and OPG, and inhibited the secretion of tumor necrosis factor‐α and RANKL in the supernatant of HG‐treated MLO‐Y4 cells. Together, this study demonstrates that mechanical vibration improves osteocytic architecture and viability, and regulates cytokine expression and secretion in the HG environment, and implies the potential great contribution of the modulation of osteocytic activities in resisting diabetic osteopenia/osteoporosis by mechanical vibration.
Cold sintering to form bulk maghemite for characterization beyond magnetic properties
Authors: Spencer Mychal P. , Lee Wonho , Alsaati Albraa , Breznak Corey M. , Braga Nogueira Branco Ricardo , Dai Jingyao , Gomez Enrique D. , Marconnet Amy , von Lockette Paris , Yamamoto Namiko
Published: August 2019

Maghemite nanoparticles have been sought after for electronic, biomedical, and environment applications, for their soft ferrimagnetic properties and large coercivity. While their magnetic properties are well characterized, their nonmagnetic properties are currently not available because maghemite is prepared as nanoparticles and their bulk forms often have contaminants. In this work, thermodynamically unstable maghemite nanoparticles are cold sintered (130‐250°C) to form bulk samples with submicron‐size grains. Electrical and thermal conductivities of maghemite were evaluated for the first time: 3.5 × 10−7 S/m and 0.86‐1.30 W/(mK). The relative densities of these cold‐sintered samples are low (55.9%‐64.2%) but comparable with or slightly lower than those previously achieved with higher sintering temperature (~55% at 500°C and ~76% at 1250°C). Such porous maghemite samples with large surface areas can potentially be used as an anode of lithium‐ion batteries, while further densification will be pursued in the future by sintering process modification.
Utilization pattern and service settings of palliative care for patients with metastatic non–small cell lung cancer
Authors: Huo Jinhai , Hong Young‐Rock , Turner Kea , Bian Jiang , Grewal Reetu , Wilkie Diana J.
Published: August 2019

Background

Although the benefits of palliative care for patients with cancer has been well established, the current utilization pattern remains largely unknown. The authors investigated the temporal trends and service settings of palliative care among Medicare beneficiaries with newly diagnosed, metastatic non–small cell lung cancer (NSCLC).

Methods

In total, 69,414 patients with NSCLC were identified between January 1, 2001 and December 31, 2013 from the Surveillance, Epidemiology, and End Results‐Medicare–linked database. Temporal trends in palliative care use and the temporal shift in palliative care service settings were assessed using the Cochran‐Armitage test. Multivariable logistic regression models were used to identify predictors for the receipt of palliative care, controlling for patients' sociodemographic and clinical characteristics.

Results

Fifteen percent (10,359) of patients with NSCLC received palliative care within 1 year of a diagnosis of metastatic NSCLC. The proportion of beneficiaries receiving palliative care increased from 3.6% in 2001 to 31.9% in 2013 (P for trend <.001). Multivariable analyses demonstrated that receipt of palliative care varied significantly by sex, race, and region. Most patients (53.5%) had their first receipt of palliative care in a hospital. Less than one‐third of patients (27.6%) received palliative care in an outpatient setting or received palliative care in more than 1 service setting (26.3%) in 2013.

Conclusions

The number of patients with metastatic NSCLC receiving palliative care has increased substantially. Although the hospital‐based program is still the main form of palliative care delivery, more patients in recent years have received palliative care services in multiple locations.
Artificial neural network approach for protection of the color of dried golden and pink oyster mushrooms with pretreatments
Authors: Gürgen Ayşenur , Yıldız Sibel
Published: August 2019

In this study, the possibilities of protecting the color of dried golden and pink mushrooms were investigated, and color parameters of dried mushrooms were modeled by artificial neural network (ANN). For this purpose, first, the golden oyster mushroom (Pleurotus citrinopileatus) and pink oyster mushroom (Pleurotus djamor) were cultivated. Then, pretreatments were applied using citric acid (CA) and potassium metabisulfite (KMS) with different rates (0.5%, 1.0%, and 1.5%) separately, excluding control group mushrooms. All mushrooms were dried for 330 minutes in a laboratory type oven at two different temperatures (40°C and 50°C) until completely dehydrated. Colorimetric values (L*, a*, and b*) were determined using Konica Minolta CM‐2600d spectrophotometer for 30 minute intervals during the drying process. The obtained data were modeled using the ANN technique. The results show that darkening of mushrooms increased as the drying temperature increased. CA and KMS showed better results for dried golden and pink mushrooms, respectively. Thanks to the pretreatment, the mushroom's original color was protected compared with control samples. All mean absolute percentage error values of models were determined, which were lower than 4.0%. It was concluded that ANN can be a good way to predict the color of dried golden and pink mushrooms (pretreated or not) with a high degree of accuracy.
Crystal Growth and Scintillation Properties of Non‐Stoichiometric Cs2LiLaBr6:Ce
Authors: Lin Jia , Wei Qinhua , Zhang Di , Tang Gao , Qin Laishun , Shi Hongsheng
Published: August 2019

Because of incongruent melting, phase separation occurs when Cs2LiLaBr6:Ce (CLLB:Ce) is grown from a melt using stoichiometric raw materials. In this study, raw materials with different amounts of excess LiBr are used to grow CLLB:Ce crystals. It is found that enough excess of LiBr is beneficial to the crystal growth of CLLB:Ce. A transparent 1 × 2‐in. CLLB:Ce single crystal is successfully grown by the vertical Bridgman method. The differential scanning calorimeter‐thermogravimetric analysis (DSC‐TG), X‐ray diffraction, and inductively coupled plasma mass spectrometry results are used to understand the crystallization behavior at different stages of the crystal growth process. The luminescence and related scintillation properties of the CLLB:Ce single crystal are investigated. The relative light output of the CLLB:Ce single crystal is about 48 000 ph MeV−1, which is 80% that of the LaBr3:Ce crystal. The energy resolution of the CLLB:Ce single crystal is 4.0% at 137Cs 662 keV.
Highly Efficient Photocatalytic Conversion of CO2 to CO Catalyzed by Surface‐Ligand‐Removed and Cd‐Rich CdSe Quantum Dots
Authors: Xia Wu , Wu Jin , Hu Jun‐Chao , Sun Shanshan , Li Ming‐De , Liu Hongfang , Lan Minhuan , Wang Feng
Published: August 2019

Surface ligand‐removed and Cd‐rich CdSe quantum dots (QDs) exhibited exceptional activity as photocatalyst for the conversion of CO2 to CO. A CO production rate up to 789 mmol g−1 h−1 was achieved in a triethylamine/dimethylformamide mixture under visible‐light irradiation. Mechanistic studies revealed that improving the Cd/Se stoichiometric ratio and exposing more active surface Cd atoms significantly enhanced the activity of CdSe QDs for CO2 photoreduction.
Phosphine‐Catalyzed β‐Selective Conjugate Addition of α‐Fluoro‐β‐ketoamides to Allenic Esters
Authors: Vaishanv Narendra Kumar , Zaheer Mohd Khalid , Kant Ruchir , Mohanan Kishor
Published: August 2019

A Strategy for the β‐selective conjugate addition of α‐fluoro‐β‐ketoamides to allenic esters has been developed via phosphine catalysis. This protocol exhibits a broad substrate scope, and a wide range of compounds bearing fluorinated quaternary carbon center was obtained in good to excellent yields. This protocol allows the use of γ‐substituted allenic esters to furnish the products with exclusive β‐selectivity.
Salt‐enhanced cultivation as a morphology engineering tool for filamentous actinomycetes: Increased production of labyrinthopeptin A1 in Actinomadura namibiensis
Authors: Tesche Sebastian , Rösemeier‐Scheumann René , Lohr Jonas , Hanke René , Büchs Jochen , Krull Rainer
Published: August 2019

Salt‐enhanced cultivation as a morphology engineering tool for the filamentous actinomycete Actinomadura namibiensis was evaluated in 500‐mL shaking flasks (working volume 100 mL) with the aim of increasing the concentration of the pharmaceutically interesting peptide labyrinthopeptin A1. Among the inorganic salts added to a complex production medium, the addition of (NH4)2SO4 led to the highest amount of labyrinthopeptin A1 production. By using 50 mM (NH4)2SO4, the labyrinthopeptin A1 concentration increased up to sevenfold compared to the non‐supplemented control, resulting in 325 mg L−1 labyrinthopeptin A1 after 10 days of cultivation. The performance of other ammonium‐ and sulfate‐containing salts (e.g., NH4Cl, K2SO4) was much lower than the performance of (NH4)2SO4. A positive correlation between the uptake of glycerol as one of the main carbon sources and nongrowth‐associated labyrinthopeptin productivity was found. The change in the cell morphology of A. namibiensis in conjunction with increased osmolality by the addition of 50 mM (NH4)2SO4, was quantified by image analysis. A. namibiensis always developed a heterogeneous morphology with pellets and loose mycelia present simultaneously. In contrast to the non‐supplemented control, the morphology of (NH4)2SO4‐supplemented cultures was characterized by smaller and circular pellets that were more stable against disintegration in the stationary production phase.
Structure and thermal property of intumescent char produced by flame‐retardant high‐impact polystyrene/expandable graphite/microencapsulated red phosphorus composite
Authors: Liu Jichun , Li Hang , Chang Haibo , He Yunpeng , Xu Airong , Pan Bingli
Published: August 2019

This paper is aimed to illustrate the structure and thermal property of intumescent char produced by flame‐retardant polymers containing expandable graphite (EG). For this purpose, high‐impact polystyrene (HIPS) flame retarded by EG individually or in combination with microencapsulated red phosphorus (MRP) was prepared. The results indicate that the intumescent char from HIPS/EG/MRP composite, which contains a small amount of phosphorus element and more oxygen element, is much more compact and continuous than that from HIPS/EG composite with identical loading of flame retardant due to binding effect of phosphoric acid and its derivatives. The intumescent char produced by HIPS/EG/MRP composite exhibits much enhanced thermal and thermo‐oxidative stability as well as thermal‐insulating effect, which can withstand destruction of heat and oxygen effectively and thus provide a good fire‐proof barrier. The temperature beneath this intumescent char is decreased significantly in case of action by flame. By comparison, the porous and loose intumescent char generated by HIPS/EG composite has poor thermo‐oxidative endurance, and most of it can be consumed in air at high temperature without effective protection for the polymer. This has resulted in remarkable increase in flame retardancy of the HIPS/EG/MRP composite.
Shape optimization of screwdriver handle for improving grasping comfort of precision and power grips
Authors: Chihara Takanori , Seo Akihiko , Sakamoto Jiro
Published: August 2019

Improving grasping comfort is a significant factor in enhancing the value of industrial products, as most products are handled by human hands. Our aim was to optimize hand tool shapes and maximize grasping comfort, considering multiple‐shape parameters and grasping types. A screwdriver handle was used as the reference tool for this case study. The measurements of handle length, end diameter, and middle diameter were utilized as the shape parameters of the handle. Twelve participants were included in this study. We measured the participants' subjective perceptions of comfort while grasping the precision and power grips during screw‐driving and screw‐tightening tasks, respectively. The design of the screwdriver handle was formulated as a bi‐objective optimization problem with respect to the grasping comfort of the precision and power grips. A Pareto frontier was determined by optimizing the formulated problem. Well‐balanced and optimal shapes for the precision and power grips were identified.