bluuebunny/crossref_metadata_2025 huggingface dataset:
Brain clusterin protein isoforms and mitochondrial localization
Authors: Herring Sarah K , Moon Hee-Jung , Rawal Punam , Chhibber Anindit , Zhao Liqin
Published: November 2019

Clusterin (CLU), or apolipoprotein J (ApoJ), is the third most predominant genetic risk factor associated with late-onset Alzheimer’s disease (LOAD). In this study, we use multiple rodent and human brain tissue and neural cell models to demonstrate that CLU is expressed as multiple isoforms that have distinct cellular or subcellular localizations in the brain. Of particular significance, we identify a non-glycosylated 45 kDa CLU isoform (mitoCLU) that is localized to the mitochondrial matrix and expressed in both rodent and human neurons and astrocytes. In addition, we show that rodent mitoCLU is translated from a non-canonical CUG (Leu) start site in Exon 3, a site that coincides with an AUG (Met) in human CLU. Last, we reveal that mitoCLU is present at the gene and protein level in the currently available CLU–/– mouse model. Collectively, these data provide foundational knowledge that is integral in elucidating the relationship between CLU and the development of LOAD.
Spatiotemporal constraints on optogenetic inactivation in cortical circuits
Authors: Li Nuo , Chen Susu , Guo Zengcai V , Chen Han , Huo Yan , Inagaki Hidehiko K , Chen Guang , Davis Courtney , Hansel David , Guo Caiying , Svoboda Karel
Published: November 2019

Optogenetics allows manipulations of genetically and spatially defined neuronal populations with excellent temporal control. However, neurons are coupled with other neurons over multiple length scales, and the effects of localized manipulations thus spread beyond the targeted neurons. We benchmarked several optogenetic methods to inactivate small regions of neocortex. Optogenetic excitation of GABAergic neurons produced more effective inactivation than light-gated ion pumps. Transgenic mice expressing the light-dependent chloride channel GtACR1 produced the most potent inactivation. Generally, inactivation spread substantially beyond the photostimulation light, caused by strong coupling between cortical neurons. Over some range of light intensity, optogenetic excitation of inhibitory neurons reduced activity in these neurons, together with pyramidal neurons, a signature of inhibition-stabilized neural networks ('paradoxical effect'). The offset of optogenetic inactivation was followed by rebound excitation in a light dose-dependent manner, limiting temporal resolution. Our data offer guidance for the design of in vivo optogenetics experiments.
Steder, stedsfortellinger og livsmot
Authors: Clancy Anne
Published: November 2019

The vital urge to live and find meaning - stories of place

This essay develops an understanding of how attachment to place and how physical, virtual and symbolic places can nurture or constrain a person’s will to carry on and find meaning. The nursing home is presented as an illustration of a physical place and the online gaming world represents a virtual place. Young and old share stories of how the symbolic meaning of place or memories of place can nurture hope and meaning. The stories also show how their attachment to place can result in a constricted understanding of who they are. Memories of vitality and envisioning themselves as strong and active create meaning and provide a welcome distraction in their everyday lives. The author mediates with the philosophies of Levinas, Tillich and Casey in order to develop an understanding of how certain places and our understanding of them can nurture or constrain a person’s will to carry on and find meaning.
Assessment of Inbreeding Depression and Inbreeding Trend of Production Traits in Iraqi Holstein Cows
Authors: Moradpour Farzad , Hamidi Hana
Published: November 2019

Inbreeding is defined as the probability that two alleles at any locus are identical by descent and occur when related individuals are mated to each other. A total of 123427, 115810 and 88361 records of 412-d yields of milk, fat and protein of Iraqi Holstein cows were collected from 1995 to 2010 in 838 herds used to estimation the inbreeding depression and inbreeding trend. Pedigree records of Iraqi Holstein cow were used to assessment inbreeding coefficients and these coefficients ranged from 0 to 42%. Animal model was used to estimation inbreeding depression on traits. Fixed effects included in statistical model were herd – year, age at calving and inbreeding coefficient as continuous and discrete variable. When considering inbreeding as continuous variable in model, the inbreeding depression for 412-d yields of milk, fat and protein were -28.19, -0.98 and -0.88 kg per 1% increase in inbreeding in Iraqi Holsteins, respectively. In this group of animal that inbreeding coefficient was between 0 < F ≤ 5.34 inbreeding was not caused reduction in production traits. However, in group of animal that inbreeding coefficient was greater than 5.34, and inbreeding depression in production traits was observed. The result of this study confirms of inbreeding depression in Iraqi Holstein cows.
Influence of Training Strategy on Growth of Small and Micro Enterprises in Kenya: A Case of Women Enterprise Fund
Authors: Nyamboga Tom Ongesa , Odhuno Edwin , Okibo Bichanga Walter
Published: November 2019

The government of Kenya established Women Enterprise Fund to enhance the growth of Small and Micro Enterprises in the country through its training strategy. The purpose of this study was to establish the influence of training strategy on growth of SMEs in Kenya. This research used a descriptive survey based design. The study’s target population was composed of group leaders’ beneficiaries of Constituency Women Enterprise Scheme. Both cluster sampling and simple random sampling were used to select a sample size of 335 respondents. Quantitative primary data was collected by use of structured questionnaires. The data collected was analyzed according to research objectives. The study utilized both descriptive statistics and inferential statistics to analyze data. Both ANONA and Regression Analysis were computed to assess the correlation between the variables. The findings of the study established that majority of clients had acquired relevant business skills. The training was given to most clients on a regular basis and enabled them to operate their SMEs more effectively. ANOVA results showed a correlation between training strategy and growth of SMEs since the calculated P value 0.001 was less than the critical value 0.005. The study therefore established a positive relationship between training strategy and growth of SMEs. The findings of this study will help the government of Kenya to formulate training strategies that would boost the growth of SMEs in the whole country. The study recommends the government to provide frequent training to all SMEs in the country to make them more efficient and effective.
Expert System Based on Rules and Medical Knowledge for the Medical Diagnosis of Typhoid Fever (XperTyph)
Authors: Cuteso Matumueni Humberto , Neto Simbo Alcides Romualdo
Published: November 2019

Today, common diseases like malaria, typhoid, cholera and others are becoming more dangerous problems for people living in this world. It is simple to use, portable, inexpensive and makes the diagnosis of typhoid faster, more efficient and more accurate, and helps doctors avoid wasting time on the diagnosis of typhoid and the publication of results. The objective is to know how to avoid the queue of patients in the hospital. In this article, the author proposed a model of expert systems using the knowledge of physicians and other health professionals. The expert system Xper Typh is useful for patients who suffer from typhoid fever. This system will give a response similar to that of a doctor or a medical expert. This system is also very useful in rural areas where we have young medical experts or no medical experts. Study cross-sectional between the Cabinda Provincial Hospital and the Center 1st of May Health in Cabinda during June 2015 and July 2018. We included 65 patients (22 men, 28 women and 15 children); age group from 5 to 75 years old. The patients examined presented different symptoms and signs. On 65 patients, 20 patients with confirmed fever, 25 patients without confirmed fever and 20 contraction patients between the expert system and the physician. The results between the doctor and the expert system are as follows: Sixty-five patients were diagnosed with XpertTyph. The XpertTyph correctly identified 20/65 (30%) of patients with typhoid fever and 25/65 (41%) of patients not suffering from typhoid fever. That is 71% concordance and 29% discrepancy. The criterion of validity of the model presented the best content for a certain level of average diagnosis for the diagnosis (k = 0.21 to 0.40) for typhoid fever which corresponds to 69% of confidence.
Qualitative Risk Assessment of Campylobacter jejuni in Street Vended Poultry in Informal Settlements of Nairobi County
Authors: Birgen Beatrice J. , Njue Lucy G. , Kaindi Dasel M. , Ogutu Fredrick O.
Published: November 2019

Aim: To determine the food safety risks of consumption of street-vended poultry products, to evaluate the determinants of microbial safety and the risk rank of these products.

Study Design: A cross-sectional survey was done in the Korogocho and Kariobangi North slums among the consumers and vendors to assess their food safety knowledge and practices. Swab samples of the cooking equipment, utensils, and personnel, raw and cooked portions of poultry were collected for microbial quality evaluation. The most prevalent microorganism was assessed for its qualitative risk rank using the Risk Ranger software.

Place and Duration of Study: The study was carried out in the capital city of Kenya, Nairobi, from June 2018 to July 2018.

Methodology: A total of 15 vendors were exhaustively sampled and included in the study with the food safety and hygiene practices evaluated using a food safety checklist. The snowballing sampling technique was used to locate all the vendors. Samples of raw and cooked street vended poultry products were subjected to microbial analysis. All samples were collected in sterile polythene bags followed by transportation to the laboratory of the Department of Food Science and Technology of the University of Nairobi and microbial analysis.

Results: Campylobacter jejuni contamination, in both raw and cooked poultry products, was 8.95±0.94 log10 CFU g-1 and 4.66±2.67 log10 CFU g-1 respectively; the probability of contamination of raw street-vended poultry was found to be 48.96%. The mean weekly intake of the poultry was reported 140.0 g per person. The probability of campylobacter infection in an individual consumer was found as 7.12x10-3 with the predicted illnesses among the population found as 1.11x106 cases. The qualitative risk estimate from the study was reported as 67, above the limit of 48 for medium risk.

Conclusion: The study concluded that Campylobacter jejuni posed high food safety risks as a resultant from the consumption of street-vended poultry.
Risk Study of Hydrocarbon Impacted Surficial Soil at the Heavy Duty Diesel Generator Plant in Delta Park University of Port Harcourt, Nigeria
Authors: Udume Ogochukwu Ann , Abu Gideon O.
Published: November 2019

Aim: To analyse the potential risk of hydrocarbon polluted surficial soil, from a heavy-duty generator plant at Delta Campus, University of Port Harcourt, Nigeria.

Study Design: Conceptual site model (CSM).

Methodology:  A CSM was designed and applied prior to sample collection in order to screen for heavy metals and other chemicals of concern (COCs) from three different high-risk points. The CSM showed a credible source-pathway-receptor chain at three high-risk points. Risk assessment associated with the heavy metals was significantly reduced based on the Department of Petroleum Resources (DPR) – Environmental Guidelines and Standards for the Petroleum Industry In Nigeria (EGASPIN) values after 28 days of bioremediation study.

Results: The hazard quotient of the target (COCs) namely Arsenic, Cadmium, Chromium and Lead was less than one (< 1). This suggests that the study area does not pose significant risk on both Adults and children.

Conclusion: The evaluation is essential for the formulation of remedial actions and risk-based management plans geared toward risk reduction. In other words, it is an approach to the determination of imminent risk posed by a pollutant to the environmental proxies. Poor education and sensitization of the public on the causal effect of pollution have been identified as a leading cause of indiscriminate pollution of the environment.
Petrophysical Application towards Achieving Optimum Secondary Recovery in Heterogeneous Reservoirs
Authors: Udoinyang I. E. , Akpan Ekere , George N. J.
Published: November 2019

Globally the challenge to meet the increasing energy demand is on with the application of game-changing technologies to maximize recovery from proven reserves in mature assets. Production studies have shown that some Niger delta fields have heterogeneous reservoirs with low to fair recovery factor derived in most cases by software simulations without adequate field acquired reservoir parameters before embarking on the secondary development plan for such reservoirs. Failures recorded in most secondary recovery strategies for heterogeneous reservoirs are accountable for lack of in-depth studies of the reservoir characteristics. There is a direct relationship between reservoir recovery factor and the petrophysics of the reservoir. A sand body in the field can exhibit variable petrophysical changes at different positions in the field. Therefore optimum secondary recovery plan for such reservoirs are designed with the combination of field acquired (not simulated) petrophysical data (porosity and permeability), the environment of deposition, special core analysis and formation evaluation studies. This study emanates from the recently developed project in a field in Niger delta.
Pharmacoinformatics: Development through History and Its Role in Pharmaceutical Industry
Authors: Ahmed Shaikh Zaffar , Orangzeb Panhwar Ali , Kumar Kamlesh , Ahmed Solangi Irfan , Parveen Panhwar Abida
Published: November 2019

Medicine has displayed miraculous developments during the past century or so. Credit goes to the emergence of scientific research methods. Research on the disease, its causes, effects, precaution, and especially cure has revolutionized the world. Man has been liberated from epidemics and other deadly diseases. All this would not have been possible, had there not been research and development in medication simultaneously. The pharmaceutical industry is an integral part of the medical field. A real boost was given to all kinds of research with the invention of the computer. Data saving, processing, and analysis were never easier. This paper aims at highlighting the great role and importance of Pharmacoinformatics in drug discovery. It also elucidates how drug discovery is done. A portion of it also targets how this science has evolved over time. The particular purpose is to trace the transformations that came with the introduction of Information Technology in this field.
Isolation, Screening and Characterization of Exopolysaccharide Producing Bacteria
Authors: Nwosu I. G. , Abu G. O. , Agwa K. O.
Published: November 2019

Exopolysaccharides(EPSs) are essential metabolites synthesized and excreted by certain microorganisms in response to extreme condition of pH, temperature, salinity, osmotic stress and other contaminants for survival in such adverse environment. The present study focuses on isolation of exopolysaccharide producing bacteria from extreme environment of oil polluted soil of Ogoni land and marine water of Bonny Island. Screening of EPS producing abilities of the selected isolates were estimated using two approaches viz gravimetric analysis of EPS dry weight and quantification assay for total carbohydrate content by phenol sulphuric acid method. Result revealed that a total of forty (40) different colonies were suspected to produce exopolysaccharide after preliminary screening by selecting thick ropy-like colony formers on agar medium. Secondary screening indicated that twelve (12) isolates produced precipitates above 1000mg/l of total dry weight and eight (8) isolates produced highest EPS yield above 1000mg/l of culture media with carbohydrate content determination. Five isolates with the code WAS1, WAS11, SC6, SOS7 and SOS10 produced significantly higher EPS compared to other bacterial colonies isolated and were termed as most potent EPS producers. These isolates were identified based on 16S rDNA sequence as Providencia stuarti, Escherichia coli, Shewanella chilikensis and Bacillus nealsonii. The result of the present study indicated that these strains have the potentials of producing high exopolysaccharides and can be explored in biotechnological industries.
Microemulsion Polymerization
Authors: Demirci Sahin , Sahiner Nurettin
Published: November 2019

In this article, recent developments in microemulsion polymerization for polymeric particles preparation are summarized. Polymeric particles with hydrophilic, hydrophobic, and amphiphilic nature can be synthesized by means of microemulsion polymerization employing different formulations. The types, the amounts, and the nature of the used surfactant, solvent, and cosolvent (if any); mixing rate; temperature; the types and the amounts of cross‐linkers (if any); and the nature of monomers and polymers are very important parameters in microemulsion polymerization determining the size and the properties of polymeric particles. These parameters that are effective in the compartmentalization of the reaction medium and their effect on size of the prepared particles are summarized.
Polymer Reaction Engineering
Authors: Saldívar‐Guerra Enrique
Published: November 2019

Polymer reaction engineering is a discipline that encompasses a set of principles and tools for the scaling up, design, analysis, control, troubleshooting, and optimization of industrial polymerization processes. Its tools are widely used in industry and are mainly taken from the fields of reaction kinetics, chemical reactor engineering, thermodynamics, physical chemistry, and applied mathematics. In this article, the basics to go from the polymerization reaction kinetics to reactor modeling are first introduced. Then, molecular weight distribution (MWDs) modeling tools are reviewed; these are classified and discussed as: analytical techniques, the method of moments, and numerical techniques for the complete MWD, covering both deterministic and stochastic methods. Next, the theoretical bases of copolymerization systems are discussed, including copolymerization models for copolymer composition and reactivity ratio estimation, to conclude with the discussion of the pseudo‐homopolymerization approach (or apparent rate constants method) for the modeling of the MWD in copolymerization systems. A section providing a general description of heterogeneous processes and their modeling is also included, covering the topics of population balance equations, suspension polymerization and emulsion polymerization. The article ends with a brief discussion of future perspectives in the field.
The Gα‐interacting vesicle‐associated protein interacts with and promotes cell surface localization of GRP78 during endoplasmic reticulum stress
Authors: Limso Clariss , Ngo Jordan Matthew , Nguyen Peter , Leal Stephanie , Husain Aida , Sahoo Debashis , Ghosh Pradipta , Bhandari Deepali
Published: November 2019

Cell surface translocation of the chaperone glucose‐regulated protein 78 kDa (GRP78) is a key event that promotes cancer cell survival during endoplasmic reticulum (ER) stress. Here, we identify Gα‐interacting vesicle‐associated protein (GIV) – an enhancer of prosurvival signaling during ER stress – as a binding partner of GRP78. We show that GIV and GRP78 interact in an ER stress‐dependent manner through their respective carboxyl terminal domains and that GIV aids in the localization of GRP78 to the plasma membrane. Kaplan–Meier analysis of disease‐free survival in cancer patients shows poor prognosis for patients with high expression of both GIV and GRP78, further suggesting a vital role for these two proteins in enhancing cancer cell viability.
Expression of CCCTC‐binding factor (CTCF) is linked to poor prognosis in prostate cancer
Authors: Höflmayer Doris , Steinhoff Amélie , Hube‐Magg Claudia , Kluth Martina , Simon Ronald , Burandt Eike , Tsourlakis Maria Christina , Minner Sarah , Sauter Guido , Büscheck Franziska , Wilczak Waldemar , Steurer Stefan , Huland Hartwig , Graefen Markus , Haese Alexander , Heinzer Hans , Schlomm Thorsten , Jacobsen Frank , Hinsch Andrea , Poos Alexandra M. , Oswald Marcus , Rippe Karsten , König Rainer , Schroeder Cornelia
Published: November 2019

The chromatin‐organizing factor CCCTC‐binding factor (CTCF) is involved in transcriptional regulation, DNA‐loop formation, and telomere maintenance. To evaluate the clinical impact of CTCF in prostate cancer, we analyzed CTCF expression by immunohistochemistry on a tissue microarray containing 17 747 prostate cancers. Normal prostate tissue showed negative to low CTCF expression, while in prostate cancers, CTCF expression was seen in 7726 of our 12 555 (61.5%) tumors and was considered low in 44.6% and high in 17% of cancers. Particularly, high CTCF expression was significantly associated with the presence of the transmembrane protease, serine 2:ETS‐related gene fusion: Only 10% of ERG‐negative cancers, but 30% of ERG‐positive cancers had high‐level CTCF expression (P < 0.0001). CTCF expression was significantly associated with advanced pathological tumor stage, high Gleason grade (P < 0.0001 each), nodal metastasis (P = 0.0122), and early biochemical recurrence (P < 0.0001). Multivariable modeling revealed that the prognostic impact of CTCF was independent from established presurgical parameters such as clinical stage and Gleason grade of the biopsy. Comparison with key molecular alterations showed strong associations with the expression of the Ki‐67 proliferation marker and presence of phosphatase and tensin homolog deletions (P < 0.0001 each). The results of our study identify CTCF expression as a candidate biomarker for prognosis assessment in prostate cancer.
Mindfulness, impulsivity, and moral disengagement as parameters of bullying and victimization at school
Authors: Georgiou Stelios N. , Charalambous Kyriakos , Stavrinides Panayotis
Published: November 2019

The aim of the present study was to examine the existing association between mindfulness, impulsivity, moral disengagement, and bullying experiences at school. Longitudinal data were collected in three points in time (T1, T2, T3) with 6 months interval between them. Participants were 558 adolescents attending secondary schools in Cyprus, with their ages ranging from 14 to 17 years (M = 15.3; standard deviation = 0.69). Through structural equation modeling, it was found that mindfulness at T1 had a significant negative effect on both impulsivity and moral disengagement at T2 and these, in turn, had a positive effect on bullying and victimization at T3. Thus, mindfulness had an indirect effect on both bullying and victimization, fully mediated by impulsivity and moral disengagement.
Multifunctional High‐Power Sources for Smart Contact Lenses
Authors: Takamatsu Taiki , Sijie Yin , Shujie Fang , Xiaohan Liu , Miyake Takeo
Published: November 2019

Powering an electrical contact lens is a significant challenge for wearable applications such as augmented reality displays and iontophoretic drug delivery to the eye. Here a hybrid power generation device is developed comprising a wireless power transfer system and a bioabsorbable metal–air primary battery, which provides a multifunctional direct current (DC) and/or alternating current (AC) output. The DC power is generated by Zn loop anode and a bilirubin oxidase (BOD) biocathode in an artificial tear. The Zn‐based loop anode is also used as the antenna of a wireless power transfer system that results in high power transfer efficiency of 17.6% at 13.56 MHz. The wireless‐powered AC voltage is boosted from 1.5 to 1.5 V + 0.5 Vpp by a DC offset, enabling red light‐emitting diode (LED) emission. Furthermore, the hybrid AC and DC offset voltages are boosted to 2.3 V + 0.5 Vpp by a capacitive booster circuit that provides blue LED emission. No hydrogen evolution or pH change is observed in the tear electrolyte. The present hybrid power source can potentially power wearable electronics in body fluids.
Boosting Efficiency of Near‐Infrared Organic Light‐Emitting Diodes with Os(II)‐Based Pyrazinyl Azolate Emitters
Authors: Yuan Yi , Liao Jia‐Ling , Ni Shao‐Fei , Jen Alex K.‐Y. , Lee Chun‐Sing , Chi Yun
Published: November 2019

Tremendous effort has been devoted to developing novel near‐infrared (NIR) emitters and to improving the performance of NIR organic light‐emitting diodes (OLEDs). Os(II) complexes are known to be an important class of NIR electroluminescent materials. However, the highest external quantum efficiency achieved so far for Os(II)‐based NIR OLEDs with an emission peak wavelength exceeding 700 nm is still lower than 3%. A new series of Os(II) complexes (1–4) based on functional pyrazinyl azolate chelates and dimethyl(phenyl)phosphane ancillaries is presented. The reduced metal‐to‐ligand charge transfer (MLCT) transition energy gap of pyrazinyl units in the excited states results in efficient NIR emission for this class of metal complexes. Consequently, NIR OLEDs based on 1–4 show excellent device performance, among which complex 4 with a triazolate fragment gives superior performance with maximum external quantum efficiency of 11.5% at peak wavelength of 710 nm, which represent the best Os(II)‐based NIR‐emitting OLEDs with peak maxima exceeding 700 nm.
Role of Excess FAI in Formation of High‐Efficiency FAPbI3‐Based Light‐Emitting Diodes
Authors: Jia Yong‐Heng , Neutzner Stefanie , Zhou Yang , Yang Ming , Tapia Jetsabel Maria Figueroa , Li Nan , Yu Hui , Cao Jie , Wang Jian‐Pu , Petrozza Annamaria , Wong Ching‐Ping , Zhao Ni
Published: November 2019

Introducing extensively excess ammonium halides when forming perovskites has recently been demonstrated as an effective approach to improve the performance of perovskite light‐emitting diodes (PeLEDs). Here, Cs0.17FA0.83PbI2.5Br0.5 is used as a model system to elucidate the impact of introducing excess formamidinium iodide (FAI) on the crystallization process of the perovskite film and operation of the corresponding PeLED. The excess FAI ratio is varied from 0 to 120 mol% and the crystallization process of the perovskite through in situ absorbance, in situ photoluminescence, and ex situ X‐ray diffraction measurements is systematically monitored. The results suggest that excess FAI triggers formation of a compact wide‐bandgap intermediate phase in the as‐deposited film, which then transforms to isolated and highly crystalline perovskite grains upon annealing. Using excitation correlation photoluminescence spectroscopy it is found that excess FAI results in a lower density of deep trap states and therefore a reduction of nonradiative losses in the material. This leads to a greatly enhanced maximum external quantum efficiency (EQE) from 0.25% (stoichiometric) to 12.7% (90 mol% excess). Furthermore, the FAI‐excess perovskite film is optimized with Pb(SCN)2 and 5‐ammonium valeric acid iodide additives and achieve a record radiance of 965 W Sr−1 m−2 for near‐infrared PeLEDs and a high EQE of 17.4%.
Tailored Redox Kinetics, Electronic Structures and Electrode/Electrolyte Interfaces for Fast and High Energy‐Density Potassium‐Organic Battery
Authors: Tong Zhongqiu , Tian Shuang , Wang Hui , Shen Dong , Yang Rui , Lee Chun‐Sing
Published: November 2019

Potassium‐organic batteries have a great potential for applications in large‐scale electricity grids and electric vehicles because of their low cost and sustainability. However, their inferior cycle stability and more importantly low energy density under fast discharge/charge process of organic cathodes limit their applications. This work introduces a simple polymerization processing which enables comprehensive tuning of redox kinetics, electronic structures, and electrode/electrolyte interfaces of the polymer cathodes. With this approach, a potassium‐organic battery with an impressive energy density of 113 Wh kg−1 at a high power of 35.2 kW kg−1 is shown which corresponds to a high current density of 147 C and a fully discharge within 10 s. The battery also has impressive cycling stability that a 100% Columbic efficiency is maintained and shows negligible capacity degradation after 1000 cycle at a high current density of 7.35 C. Using the polymer cathode and a dipotassium terephthalate anode, a full battery with superior energy density and cycling stability is demonstrated among all reported all‐organic full potassium ion batteries.
Fast‐Response, Highly Air‐Stable, and Water‐Resistant Organic Photodetectors Based on a Single‐Crystal Pt Complex
Authors: Periyanagounder Dharmaraj , Wei Tzu‐Chiao , Li Ting‐You , Lin Chun‐Ho , Gonçalves Théo Piechota , Fu Hui‐Chun , Tsai Dung‐Sheng , Ke Jr‐Jian , Kuo Hung‐Wei , Huang Kuo‐Wei , Lu Norman , Fang Xiaosheng , He Jr‐Hau
Published: November 2019

Organic semiconductors demonstrate several advantages over conventional inorganic materials for novel electronic and optoelectronic applications, including molecularly tunable properties, flexibility, low‐cost, and facile device integration. However, before organic semiconductors can be used for the next‐generation devices, such as ultrafast photodetectors (PDs), it is necessary to develop new materials that feature both high mobility and ambient stability. Toward this goal, a highly stable PD based on the organic single crystal [PtBr2(5,5′‐bis(CF3CH2OCH2)‐2,2′‐bpy)] (or “Pt complex (1o)”) is demonstrated as the active semiconductor channel—a material that features a lamellar molecular structure and high‐quality, intraligand charge transfer. Benefitting from its unique crystal structure, the Pt‐complex (1o) device exhibits a field‐effect mobility of ≈0.45 cm2 V−1 s−1 without loss of significant performance under ambient conditions even after 40 days without encapsulation, as well as immersion in distilled water for a period of 24 h. Furthermore, the device features a maximum photoresponsivity of 1 × 103 A W−1, a detectivity of 1.1 × 1012 cm Hz1/2 W−1, and a record fast response/recovery time of 80/90 µs, which has never been previously achieved in other organic PDs. These findings strongly support and promote the use of the single‐crystal Pt complex (1o) in next‐generation organic optoelectronic devices.
Decoding the Polymer p–n Junction: Controlled Dedoping and Reverse Bias Electroluminescence
Authors: Wang Dongze , Desroche Emmett , Gao Jun
Published: November 2019

The polymer light‐emitting electrochemical cell (PLEC) is a unique solid‐state device possessing attractive attributes for low‐cost applications, but also a junction structure that is still poorly understood. In a PLEC, the applied voltage causes in situ electrochemical p‐ and n‐doping of the semiconducting polymer and the formation of a dynamic light‐emitting p–n junction. Once the junction is fixed by cooling or chemical manipulation, the “frozen‐junction” PLEC exhibits a unipolar electroluminescence (EL) and photovoltaic response. Repeated thermal cycling, however, can cause the frozen‐junction PLEC to experience drastically enhanced EL under forward bias and the emergence of reverse bias EL. In this study, a combination of transport measurements and direct imaging is used to elucidate the origin of the mysterious reverse bias EL. A model is developed that explains the reverse bias EL as caused by the tunnel injection of electrons and holes from bandgap states into a dedoped “intrinsic” region between the p‐ and n‐doped regions. The model explains the location, relative intensity, and evolution of EL under both forward and reverse bias. The results hint at a junction that is much narrower than previously resolved.
Tuning Areal Density and Surface Passivation of ZnO Nanowire Array Enable Efficient PbS QDs Solar Cells with Enhanced Current Density
Authors: Tavakoli Dastjerdi Hadi , Prochowicz Daniel , Yadav Pankaj , Tavakoli Mohammad Mahdi
Published: November 2019

Colloidal PbS quantum dots (QDs) have provoked a revolution in the field of optoelectronic devices owing to their low‐cost fabrication processing and excellent physical properties. Recently, the fabrication of nanostructured PbS QD photovoltaic (PV) devices based on zinc oxide (ZnO) nanowire array appears as an effective strategy for improving the overall device performance. Despite its potentially strong impact on the device performance, the role of nanowire areal density on photon absorption and exciton dynamics has not yet been studied and still remains unexplored. Here, for the first time, the areal density of ZnO nanowires is tuned through controlling the precursor concentration and its impact on PbS QD PV performance is studied. It is found that the device with optimized ZnO nanowire areal density yields significantly increased power conversion efficiency (PCE) (10.1% vs 8.5% of control nanowire‐based device) due to improved antireflection effect and reduced surface recombination states. To further improve the photovoltaic performance, the ZnO nanowire surface is treated with hydrogen plasma. Transient photovoltage (TPV) measurement reveals that this passivation process noticeably reduces the nonradiative charge recombination yielding a champion device with a remarkable PCE of 10.8%.
Conducting Polymer‐Based Biocomposites Using Deoxyribonucleic Acid (DNA) as Counterion
Authors: Tekoglu Serpil , Wielend Dominik , Scharber Markus Clark , Sariciftci Niyazi Serdar , Yumusak Cigdem
Published: November 2019

In this work, the preparation of conducting polymer‐based composites using a biological anionic polymer based on salmon deoxyribonucleic acid (DNA) is presented. The most commonly used polymers poly(3,4‐ethylenedioxythiophene) (PEDOT), as well as polypyrrole, are polymerized in the presence of DNA. Since conjugated polymers are in the polycationic state in their electrically conducting form, the role of the counterion is now fulfilled by the low cost biomolecule DNA as an alternative material, which is also a polyanion thanks to its phosphate chain. The resulting synthesized material is a conducting polymer–DNA biocomposite. Such materials are highly attractive for the rising field of bioelectronics and biosensors, especially in organic electrochemical transistors (OECTs) and ion pumps. OECTs made of these conducting polymer biocomposites are fabricated and their electrochemical device operation is compared to the most widely used PEDOT:polystyrenesulfonate.
A Machine Learning Tool for Materials Informatics
Authors: Wang Zhi‐Lei , Ogawa Toshio , Adachi Yoshitaka
Published: November 2019

In response to the increasing demand for the highly efficient design of materials, materials informatics has been proposed for using data and computational sciences to extract data features that provide insight into how properties track with microstructure variables. However, the general metrics of microstructural features often ignore the complexities of the microstructure geometry for many properties of interest. An independently developed machine learning tool called shiny materials genome integration system for phase and property analysis (ShinyMIPHA), which is designed with either standalone software or cloud system based on an R programing package of “Shiny”, is introduced. ShinyMIPHA provides topological microstructure analysis methods based on image processing technology by employing a two‐point correlation function, persistent homology, and mean (H)–Gauss (K) curvature approaches, as well as sparse study and regression analysis methods that enable a data‐driven properties‐to‐microstructure‐to‐processing inverse materials‐design approach. The demo version is available athttps://adachi-lab.shinyapps.io/demo/.
Electromagnetic Vorticity in a Square‐Well Crystal System Described by a Supersymmetric Wave‐Equation
Authors: Manzetti Sergio , Trounev Alexander
Published: November 2019

Vortices occur under all electromagnetic phenomena in quantized systems, as well as macroscopic systems. In particular, vorticity in square‐wells is of great appeal to the scientific community, as it models electromagnetic fields and formation of condensates in crystal lattices. A supersymmetric wave‐equation (SWE) is devised to model vorticity in a square‐well system, and the numerical results of several states of vorticity are shown by increased energy of the system. It is shown that square‐well vorticity obeys specific symmetries when modeled with the SWE and generates non‐overlapping vortices of the same spin. Nucleation of vortices when subjected to increased angular velocity and formation of giant vortices is also shown. This is of importance to the modeling of magnetism in quantum systems, and the generation of new results to describe quantum vorticity.
Lightweight and Flexible Cotton Aerogel Composites for Electromagnetic Absorption and Shielding Applications
Authors: Cheng Yan , Zhao Huanqin , Lv Hualiang , Shi Tengfei , Ji Guangbin , Hou Yanglong
Published: November 2019

Currently, a versatile route is urgently required to achieve excellent electromagnetic wave (EMW) absorption and shielding functions simultaneously. A lightweight, flexible and sustainable 3D framework aerogel is designed to reach this goal, which is assembled by unique “1D‐1D” combination, nanoscale carbon nanotubes (CNTs) grown on microscale carbon fiber. EM absorption requires appropriate conductivity of filler to acquire moderate permittivity. On the contrary, EM shielding requires great conductivity to reflect most of the incident EMW. Based on this design concept, the change of electric conductivity of as‐obtained samples through in situ regulation of the growth state of CNTs is successfully controlled. When the CNTs are short and curly, the optimized conductivity favors excellent microwave absorption with wide absorption bandwidth of 5.08 GHz at only 1.6 mm. When the CNTs are long and straight, the increased conductivity is clearly boosted with 29.8 dB EM shielding effectiveness. This elaborate architecture and controlled CNT growth allow the designed 3D framework aerogel to be applied in both EM wave absorption and shielding. This conductivity tunable route gives inspiration for fabricating other efficient EM absorption and shielding devices.
Large Piezoelectricity in Ternary Lead‐Free Single Crystals
Authors: Wang Yaojin , Luo Chengtao , Wang Shuhao , Chen Chao , Yuan Guoliang , Luo Haosu , Viehland Dwight
Published: November 2019

Since industry‐standard piezoelectric materials, such as lead zirconium titanate ceramics, contain toxic lead, a rapid surge in research on lead‐free piezoelectric materials is occurring due to concerns over environmental safety and human health. A ternary lead‐free (Na0.5Bi0.5)TiO3‐BaTiO3‐(K0.5Na0.5)NbO3 single crystal with a large field induced strain of ≈0.9% and a giant piezoelectric coefficient d33 of 840 pC N−1 at room temperature is reported. It is revealed that the electric‐field‐induced phase transition and phase boundary between energetically comparable polar states (i.e., R3c and P4mm) play an important role in achieving the ultrahigh piezoelectricity. Transmission electron microscopy and scan probe microscopy are employed to verify the weak‐polar ferroelectric R3c and P4bm structure in the ground state. These unprecedentedly high piezoelectric properties make lead‐free ternary single crystals a leading candidate for piezoelectric‐based device applications, especially toward the era of smart homes and implantable medical devices.
Re‐assessing the applicability of the Jarman/Bell model and Kay's threshold to the insectivorous aye‐aye (Daubentonia madagascariensis)
Authors: Sefczek Timothy M. , Randimbiharinirina Doménico R. , Raharivololona Brigitte M. , Razafimahaleo Harison , Randrianarison Olivier , Louis Edward E.
Published: November 2019

Objectives

Jarman/Bell principle and Kay's threshold suggest that large animals should not be able to sustain themselves on insects. However, animals with specialized morphological and/or behavioral adaptations violate these assumptions. Male aye‐ayes were recently identified as having an insectivorous diet despite weighing 2.5 kg. We further explored this diet/body size disparity by studying behaviors of an adult female and juvenile male aye‐aye.

Materials and Methods

We collected behavioral data on an adult female and juvenile male aye‐aye in Torotorofotsy, Madagascar from January 2016 to December 2017. We used instantaneous sampling to determine the frequency of feeding events and continuous sampling during feeding behaviors to assess duration of feeding bouts.

Results

Invertebrates comprised over 88% of the diet for both animals. A Wilcoxon signed‐rank test found no significant difference in the female's feeding frequencies between the hot/rainy seasons and the cold/dry seasons.

Discussion

Our results support earlier findings that invertebrates are the aye‐aye's main resource and corroborate that aye‐ayes violate assumptions of the Jarman/Bell model and Kay's threshold. We suggest that the Jarman/Bell principle and Kay's threshold be used as supporting evidence and not to repudiate findings that do not conform to these guidelines.
Modeling the Ultrafast Response of Two‐Magnon Raman Excitations in Antiferromagnets on the Femtosecond Timescale
Authors: Batignani Giovanni , Pontecorvo Emanuele , Bossini Davide , Ferrante Carino , Fumero Giuseppe , Cerullo Giulio , Mukamel Shaul , Scopigno Tullio
Published: November 2019

Illuminating a magnetic material with femtosecond laser pulses induces complex ultrafast dynamical processes. The resulting optically detectable response usually contains contributions from both the optical properties and the magnetic degrees of freedom. Disentangling all the different components concurring to the generation of the total signal is a major challenge of contemporary experimental solid‐state physics. Here, this problem is tackled, addressing the purely optical, nonmagnetic artifacts on the time resolved two‐magnon stimulated Raman spectrum of an antiferromagnet, rationalizing the recent observation on the exchange energy modification upon photo‐excitation. It is demonstrated how the genuine dynamics of the magnetic eigenmode can be disentangled from the nonlinear optical effects, generated by cross phase modulation, on the femtosecond timescale. The introduced approach can be extended for the investigation of <100 fs dynamic processes by means of coherent Raman scattering.
Towards a better understanding of the release mechanisms of caffeine from PLGA microparticles
Authors: Tamani Fahima , Hamoudi Mounira Chérifa , Danede Florence , Willart Jean‐François , Siepmann Florence , Siepmann Juergen
Published: November 2019

Poly(lactic‐co‐glycolic acid) (PLGA)‐based microparticles can be successfully used to control the release rate of a drug and optimize the therapeutic efficacy of a medical treatment. However, the underlying drug release mechanisms can be complex and are often not fully understood. This renders system optimization cumbersome. In this study, differently sized caffeine‐loaded PLGA microparticles were prepared and the swelling and drug release behaviors of single microparticles were monitored upon exposure to phosphate buffer pH 7.4. Ensembles of microparticles were characterized by X‐ray diffraction, differential scanning calorimetry, scanning electron microscopy, gel permeation chromatography, and optical microscopy. The observed triphasic drug release patterns could be explained as follows. The initial burst release can be attributed to the dissolution of tiny drug crystals with direct surface access. The subsequent second drug release phase (with an about constant release rate) could be attributed to the release of drug crystals in regions, which undergo local swelling. The third release phase (again rapid, leading to complete drug exhaust) could be explained by substantial polymer swelling throughout the systems. Once a critical polymer molecular weight is reached, the PLGA chains are sufficiently hydrophilic, insufficiently entangled and the osmotic pressure created by water soluble degradation products attracts high amounts of water into the system. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48710.
Attempting to prepare a plastic scintillator from a biobased polymer
Authors: Hamel Matthieu , Lebouteiller Guillaume
Published: November 2019

A new plastic scintillator was prepared from a renewable polymer source. It is composed of the mighty 2,5‐diphenyloxazole and 1, 4‐bis(2‐methylstyryl)benzene molecules (PPO and bis‐MSB), acting as primary and secondary fluorophores, respectively, together dissolved in a polylactic acid matrix—PLA. This polymer is indeed considered as the biomass‐based equivalent of petroleum‐derived plastics in terms of mechanical and optical properties. Subsequent to the bis‐MSB emission, the emission wavelength is centered around 424 nm and the fluorescence decay time is in the nanosecond range. The material was fully characterized, and its scintillation performances were compared to a commercial PVT‐based plastic scintillator: EJ‐200. Like polystyrene‐ or polyvinyltoluene‐based scintillators, the material displayed a good response linearity with the energy of the incident gamma‐ray. However, the observed scintillation yield was rather modest, with a reported 500 ph/MeV value when excited with a gamma‐ray‐emitting 60Co source. This preliminary test could pave the way to new and renewable polymers for unexpected applications such as nuclear physics. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48724.
Long‐term trends in tropical cyclone tracks around Korea and Japan in late summer and early fall
Authors: Lee Minkyu , Cha Dong‐Hyun , Moon Jihong , Park Jinyoung , Jin Chun‐Sil , Chan Johnny C. L.
Published: November 2019

This study investigates long‐term trends in tropical cyclones (TCs) over the extratropical western North Pacific (WNP) over a period of 35 years (1982–2016). The area analyzed extended across 30–45°N and 120–150°E, including the regions of Korea and Japan that were seriously affected by TCs. The northward migration of TCs over the WNP to the mid‐latitudes showed a sharp increase in early fall. In addition, the duration of TCs over the WNP that migrated northwards showed an increase, specifically in early to mid‐September. Therefore, more recently, TC tracks have been observed to significantly extend into the mid‐latitudes. The recent northward extension of TC tracks over the WNP in early fall was observed to be associated with changes in environmental conditions that were favorable for TC activities, including an increase in sea surface temperature (SST), decrease in vertical wind shear, expansion of subtropical highs, strong easterly steering winds, and an increase in relative vorticity. In contrast, northward migrations of TCs to Korea and Japan showed a decline in late August, because of the presence of unfavorable environmental conditions for TC activities. These changes in environmental conditions, such as SST and vertical wind shear, can be partially associated with the Pacific decadal oscillation.