bluuebunny/crossref_metadata_2025 huggingface dataset:
Differences Between Central Venous and Cerebral Tissue Oxygen Saturation in Anaesthetised Patients With Diabetes Mellitus
Authors: Sudy Roberta , Petak Ferenc , Schranc Almos , Agocs Szilvia , Blaskovics Ivett , Lengyel Csaba , Babik Barna
Published: December 2019

The brain has high oxygen extraction, thus the regional cerebral tissue oxygen saturation (rSO2) is lower than the central venous oxygen saturation (ScvO2). We hypothesised that diabetes widens the physiological saturation gap between ScvO2 and rSO2 (gSO2), and the width of this gap may vary during various phases of cardiac surgery. Cardiac surgery patients with (n = 48) and without (n = 91) type 2 diabetes mellitus (T2DM) underwent either off-pump coronary artery bypass (OPCAB) or other cardiac surgery necessitating cardiopulmonary bypass (CPB) were enrolled. rSO2 was measured by near-infrared spectroscopy (NIRS) and ScvO2 was determined simultaneously from central venous blood. rSO2 was registered before and after anaesthesia induction and at different stages of the surgery. ScvO2 did not differ between the T2DM and control patients at any stage of surgery, whereas rSO2 was lower in T2DM patients, compared to the control group before anaesthesia induction (60.4 ± 8.1%[SD] vs. 67.2 ± 7.9%, p<0.05), and this difference was maintained throughout the surgery. After anaesthesia induction, the gSO2 was higher in diabetic patients undergoing CPB (20.2 ± 10.4% vs. 12.4 ± 8.6%, p < 0.05) and OPCAB grafting surgeries (17.0 ± 7.5% vs. 9.5 ± 7.8%, p < 0.05). While gSO2 increased at the beginning of CPB in T2DM and control patients, no significant intraoperative changes were observed during the OPCAB surgery. The wide gap between ScvO2 and rSO2 and their uncoupled relationship in patients with diabetes indicate that disturbances in the cortical oxygen saturation cannot be predicted from the global clinical parameter, the ScvO2. Thus, our findings advocate the monitoring value of NIRS in T2DM.
Habitual physical activity mediates the acute exercise-induced modulation of anxiety-related amygdala functional connectivity
Authors: Chen Yu-Chun , Chen Chenyi , Martínez Róger Marcelo , Etnier Jennifer L. , Cheng Yawei
Published: December 2019

Aerobic exercise, in relation to physical activity, has been shown to have beneficial effects on anxiety. However, the underlyig neural mechanism remains elusive. Using a within-subject crossover design, this fMRI study examined how exercise (12-min treadmill running versus walking) mediated amygdala reactivity to explicit and implicit (backward masked) perception of emotional faces in young adults (N = 40). Results showed that acute exercise-induced differences of state anxiety (STAI-S) varied as a function of individual’s habitual physical activity (IPAQ). Subjects with high IPAQ levels showed significant STAI-S reduction (P < 0.05). Path analyses indicated that IPAQ explained 14.67% of the variance in acute exercise-induced STAI-S differences. Running elicited stronger amygdala reactivity to implicit happiness than fear, whereas walking did the opposite. The exercise-induced amygdala reactivity to explicit fear was associated with the IPAQ scores and STAI-S differences. Moreover, after running, the amygdala exhibited a positive functional connectivity with the orbitofrontal cortex and insula to implicit happiness, but a negative connectivity with the parahippocampus and subgenual cingulate to implicit fear. The findings suggest that habitual physical activity could mediate acute exercise-induced anxiolytic effects in regards to amygdala reactivity, and help establish exercise training as a form of anxiolytic therapy towards clinical applications.
MitosRNAs and extreme anoxia tolerance in embryos of the annual killifish Austrofundulus limnaeus
Authors: Riggs Claire L. , Woll Steven Cody , Podrabsky Jason E.
Published: December 2019

Embryos of the annual killifish Austrofundulus limnaeus are the most anoxia-tolerant vertebrate. Annual killifish inhabit ephemeral ponds, producing drought and anoxia-tolerant embryos, which allows the species to persist generation after generation. Anoxia tolerance and physiology vary by developmental stage, creating a unique opportunity for comparative study within the species. A recent study of small ncRNA expression in A. limnaeus embryos in response to anoxia and aerobic recovery revealed small ncRNAs with expression patterns that suggest a role in supporting anoxia tolerance. MitosRNAs, small ncRNAs derived from the mitochondrial genome, emerged as an interesting group of these sequences. MitosRNAs derived from mitochondrial tRNAs were differentially expressed in developing embryos and isolated cells exhibiting extreme anoxia tolerance. In this study we focus on expression of mitosRNAs derived from tRNA-cysteine, and their subcellular and organismal localization in order to consider possible function. These tRNA-cys mitosRNAs appear enriched in the mitochondria, particularly near the nucleus, and also appear to be present in the cytoplasm. We provide evidence that mitosRNAs are generated in the mitochondria in response to anoxia, though the precise mechanism of biosynthesis remains unclear. MitosRNAs derived from tRNA-cys localize to numerous tissues, and increase in the anterior brain during anoxia. We hypothesize that these RNAs may play a role in regulating gene expression that supports extreme anoxia tolerance.
Temporal development of the oral microbiome and prediction of early childhood caries
Authors: Dashper S. G. , Mitchell H. L. , Lê Cao K.-A. , Carpenter L. , Gussy M. G. , Calache H. , Gladman S. L. , Bulach D. M. , Hoffmann B. , Catmull D. V. , Pruilh S. , Johnson S. , Gibbs L. , Amezdroz E. , Bhatnagar U. , Seemann T. , Mnatzaganian G. , Manton D. J. , Reynolds E. C.
Published: December 2019

Human microbiomes are predicted to assemble in a reproducible and ordered manner yet there is limited knowledge on the development of the complex bacterial communities that constitute the oral microbiome. The oral microbiome plays major roles in many oral diseases including early childhood caries (ECC), which afflicts up to 70% of children in some countries. Saliva contains oral bacteria that are indicative of the whole oral microbiome and may have the ability to reflect the dysbiosis in supragingival plaque communities that initiates the clinical manifestations of ECC. The aim of this study was to determine the assembly of the oral microbiome during the first four years of life and compare it with the clinical development of ECC. The oral microbiomes of 134 children enrolled in a birth cohort study were determined at six ages between two months and four years-of-age and their mother’s oral microbiome was determined at a single time point. We identified and quantified 356 operational taxonomic units (OTUs) of bacteria in saliva by sequencing the V4 region of the bacterial 16S RNA genes. Bacterial alpha diversity increased from a mean of 31 OTUs in the saliva of infants at 1.9 months-of-age to 84 OTUs at 39 months-of-age. The oral microbiome showed a distinct shift in composition as the children matured. The microbiome data were compared with the clinical development of ECC in the cohort at 39, 48, and 60 months-of-age as determined by ICDAS-II assessment. Streptococcus mutans was the most discriminatory oral bacterial species between health and current disease, with an increased abundance in disease. Overall our study demonstrates an ordered temporal development of the oral microbiome, describes a limited core oral microbiome and indicates that saliva testing of infants may help predict ECC risk.
Raman spectroscopy as a non-invasive diagnostic technique for endometriosis
Authors: Parlatan Ugur , Inanc Medine Tuna , Ozgor Bahar Yuksel , Oral Engin , Bastu Ercan , Unlu Mehmet Burcin , Basar Gunay
Published: December 2019

Endometriosis is a condition in which the endometrium, the layer of tissue that usually covers the inside of the uterus, grows outside the uterus. One of its severe effects is sub-fertility. The exact reason for endometriosis is still unknown and under investigation. Tracking the symptoms is not sufficient for diagnosing the disease. A successful diagnosis can only be made using laparoscopy. During the disease, the amount of some molecules (i.e., proteins, antigens) changes in the blood. Raman spectroscopy provides information about biochemicals without using dyes or external labels. In this study, Raman spectroscopy is used as a non-invasive diagnostic method for endometriosis. The Raman spectra of 94 serum samples acquired from 49 patients and 45 healthy individuals were compared for this study. Principal Component Analysis (PCA), k- Nearest Neighbors (kNN), and Support Vector Machines (SVM) were used in the analysis. According to the results (using 80 measurements for training and 14 measurements for the test set), it was found that kNN-weighted gave the best classification model with sensitivity and specificity values of 80.5% and 89.7%, respectively. Testing the model with unseen data yielded a sensitivity value of 100% and a specificity value of 100%. To the best of our knowledge, this is the first study in which Raman spectroscopy was used in combination with PCA and classification algorithms as a non-invasive method applied on blood sera for the diagnosis of endometriosis.
Vitamin C and aroma composition of fresh leaves from Kalanchoe pinnata and Kalanchoe daigremontiana
Authors: Zawirska-Wojtasiak Renata , Jankowska Beata , Piechowska Paulina , Mildner-Szkudlarz Sylwia
Published: December 2019

Species of kalanchoe are rich in bioactive compounds and are widely used in folk medicine; however, these plants are not well known from the point of view of aroma. Two species, Kalanchoe pinnata and Kalanchoe daigremontiana, were examined after six months and two years of growth and their vitamin C content, succulence, and aroma composition were determined. The efficiency of juice extraction was highest (72%) for the leaves of K. daigremontiana after six months of growth. The concentration of vitamin C was highest in juices from two-year-old plants and much higher in the juice of K. pinnata (81 mg/100 g). SPME/GC/MS analysis identified 32 aroma components, considering those with the spectrum similarity over 75%. The main components were furan-2-ethyl, hexanal, 2-hexenal, 2,4-hexadienal, 1-octen-3-ol, nonanal. The quantitative relations of these compounds were somewhat different in the two species. The most dominant component, 2-hexenal, is responsible for the green-like aroma noted by the sensory panel.
Circular METRN RNA hsa_circ_0037251 Promotes Glioma Progression by Sponging miR-1229-3p and Regulating mTOR Expression
Authors: Cao Qinchen , Shi Yonggang , Wang Xinxin , Yang Jing , Mi Yin , Zhai Guan , Zhang Mingzhi
Published: December 2019

Circular RNAs (circRNAs) are a newly identifed non-coding RNA in many cellular processes and tumours. This study aimed to investigate the role of hsa_circ_0037251, one circRNA generated from several exons of the gene termed METRN, in glioma progression. Through in vitro experiments, we discovered that high expression of hsa_circ_0037251 was related to low expression of the microRNA miR-1229-3p and high expression of mTOR. The over-expressed hsa_circ_0037251 promoted cell proliferation, invasion and migration in glioma, while knockdown of hsa_circ_00037251 promoted cell apoptosis and induced G1 phase arrest. Then, hsa_circ_0037251 was observed to directly sponge miR-1229-3p, and mTOR was identified as a direct target of miR-1229-3p. In addition, knockdown of hsa_circ_0037251 up-regulated the expression of miR-1229-3p and inhibited the expression of mTOR. And overexpression of miR-1229-3p or low-expressed mTOR inhibited the glioma cell progression. Furthermore, transfection with mTOR overexpression vectors can restore the abilities of glioma cell progression even if hsa_circ_00037251 was knocked down using siRNAs. In vivo experiments revealed that hsa_circ_00037251 promoted the growth of xenografted tumours and shortened the survival period. These results indicated that hsa_circ_0037251 may act as a tumour promoter by a hsa_circ_0037251/miR-1229-3p/mTOR axis, and these potential biomarkers may be therapeutic targets for glioma.
Prefrontal parvalbumin cells are sensitive to stress and mediate anxiety-related behaviors in female mice
Authors: Page Chloe E. , Shepard Ryan , Heslin Kelsey , Coutellier Laurence
Published: December 2019

Reduced activity of the prefrontal cortex (PFC) is seen in mood disorders including depression and anxiety. The mechanisms of this hypofrontality remain unclear. Because of their specific physiological properties, parvalbumin-expressing (PV+) inhibitory interneurons contribute to the overall activity of the PFC. Our recent work using a chronic stress mouse model showed that stress-induced increases in prefrontal PV expression correlates with increased anxiety-like behaviors in female mice. Our goal is now to provide a causal relationship between changes in prefrontal PV+ cells and changes in emotional behaviors in mice. We first show that, in addition to increasing overall level of PV expression, chronic stress increases the activity of prefrontal PV+ cells. We then used a chemogenetic approach to mimic the effects of chronic stress and specifically increase the activity of prefrontal PV+ cells. We observed that chemogenetic activation of PV+ cells caused an overall reduction in prefrontal activity, and that chronic activation of PV+ cells lead to increased anxiety-related behaviors in female mice only. These results demonstrate that activity of prefrontal PV+ cells could represent a novel sex-specific modulator of anxiety-related behaviors, potentially through changes in overall prefrontal activity. The findings also support the idea that prefrontal PV+ cells are worth further investigation to better understand mood disorders that are more prevalent in female populations.
A Structurally-Validated Multiple Sequence Alignment of 497 Human Protein Kinase Domains
Authors: Modi Vivek , Dunbrack Roland L.
Published: December 2019

Studies on the structures and functions of individual kinases have been used to understand the biological properties of other kinases that do not yet have experimental structures. The key factor in accurate inference by homology is an accurate sequence alignment. We present a parsimonious, structure-based multiple sequence alignment (MSA) of 497 human protein kinase domains excluding atypical kinases. The alignment is arranged in 17 blocks of conserved regions and unaligned blocks in between that contain insertions of varying lengths present in only a subset of kinases. The aligned blocks contain well-conserved elements of secondary structure and well-known functional motifs, such as the DFG and HRD motifs. From pairwise, all-against-all alignment of 272 human kinase structures, we estimate the accuracy of our MSA to be 97%. The remaining inaccuracy comes from a few structures with shifted elements of secondary structure, and from the boundaries of aligned and unaligned regions, where compromises need to be made to encompass the majority of kinases. A new phylogeny of the protein kinase domains in the human genome based on our alignment indicates that ten kinases previously labeled as “OTHER” can be confidently placed into the CAMK group. These kinases comprise the Aurora kinases, Polo kinases, and calcium/calmodulin-dependent kinase kinases.
Electrocatalytic reduction of carbon dioxide: opportunities with heterogeneous molecular catalysts
Authors: Sun Libo , Reddu Vikas , Fisher Adrian C. , Wang Xin
Published: December 2019

Electrocatalytic CO2 reduction by heterogeneous molecular catalysts is emerging as an important area for CO2 utilization.
Multi-objective optimization of water treatment operations for disinfection byproduct control
Authors: Raseman William J. , Kasprzyk Joseph R. , Summers R. Scott , Hohner Amanda K. , Rosario-Ortiz Fernando L.
Published: December 2019

This paper introduces a novel decision-making framework for the optimization of water treatment plant operations.
A proteome-integrated, carbon source dependent genetic regulatory network in Saccharomyces cerevisiae
Authors: Garcia-Albornoz M. , Holman S. W. , Antonisse T. , Daran-Lapujade P. , Teusink B. , Beynon R. J. , Hubbard S. J.
Published: December 2019

Integrated regulatory networks can be powerful tools to examine and test properties of cellular systems, such as modelling environmental effects on the molecular bioeconomy, where protein levels are altered in response to changes in growth conditions.
RETRACTED: Characterising the spatial and temporal brain metal profile in a mouse model of tauopathy
Authors: Rao Shalini S , Lago Larissa , Gonzalez de Vega Raquel , Bray Lisa , Hare Dominic J , Clases David , Doble Philip A , Adlard Paul A
Published: December 2019

A dysregulation in the homeostasis of metals such as copper, iron and zinc is speculated to be involved in the pathogenesis of tauopathies, which includes Alzheimer's disease (AD). In particular, there is a growing body of evidence to support a role for iron in facilitating the hyperphosphorylation and aggregation of the tau protein into neurofibrillary tangles (NFTs) – a primary neuropathological hallmark of tauopathies. Therefore, the aim of this study was to characterize the spatial and temporal brain metallomic profile in a mouse model of tauopathy (rTg(tauP301L)4510), so as to provide some insight into the potential interaction between tau pathology and iron. Using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), our results revealed an age-dependent increase in brain iron levels in both WT and rTg(tauP301L)4510 mice. In addition, size exclusion chromatography-ICP-MS (SEC-ICP-MS) revealed significant age-related changes in iron bound to metalloproteins such as ferritin. The outcomes from this study may provide valuable insight into the inter-relationship between iron and tau in ageing and neurodegeneration.
The substituent guest effect on four-step spin-crossover behavior
Authors: Zhang Cui-Juan , Lian Kai-Ting , Wu Si-Guo , Liu Yang , Huang Guo-Zhang , Ni Zhao-Ping , Tong Ming-Liang
Published: December 2019

The fluoro substituent strategy on the guest in a three-dimensional Hofmann-type metal–organic framework is explored for four-step spin-crossover properties.
Construction of a bimetallic nickel–cobalt selenide pompon used as a superior anode material for high performance sodium storage
Authors: Zhong Wei , Ma Qianru , Tang Wenwen , Wu Yuanke , Gao Wei , Yang Qiuju , Yang Jingang , Xu Maowen
Published: December 2019

Pompon-like NiCo2Se4 can effectively promote the penetration of an electrolyte, increase electron and ion diffusion channels, alleviate volume expansion and achieve excellent sodium storage performance.
Microwave-assisted in situ large scale synthesis of a carbon dots@g-C3N4 composite phosphor for white light-emitting devices
Authors: Meng Li , Ushakova Elena V. , Zhou Zhengjie , Liu Enshan , Li Di , Zhou Ding , Tan Zhanao , Qu Songnan , Rogach Andrey L.
Published: December 2019

A composite phosphor comprising carbon dots and g-C3N4 is prepared on a large scale through a green microwave assisted in situ heating method, and is used for fabrication of white LEDs with a power efficiency of up to 42 lm W−1.
Microscopic visualization and mechanism investigation of the crystal jumping behavior of a cyclic chalcone derivative
Authors: Cheng Xiao , Yang Fulin , Zhao Jian , Ni Juechen , He Xinrui , Zhou Chuanjian , Sun Jing Zhi , Tang Ben Zhong
Published: December 2019

A highly emissive chalcone crystal which displays fantastic photo-induced jumping behavior is designed and the microscopic dynamic process is easily visualized and captured. The motion mechanism is demonstrated to be a [2+2] cycloaddition reaction.
The stability and reaction mechanism of a LiF/electrolyte interface: insight from density functional theory
Authors: Zhang Bingkai , Lin Zhan , Chen Haibiao , Wang Lin-Wang , Pan Feng
Published: December 2019

A molecular-level understanding of interfacial reactions and dynamics at the sLiF/LE interface in Li-metal battery systems inspire future work in sLiF coating layer for electrode and electrolyte applications.
A composite solid polymer electrolyte incorporating MnO2 nanosheets with reinforced mechanical properties and electrochemical stability for lithium metal batteries
Authors: Li Yuhan , Sun Zongjie , Liu Dongyu , Gao Yiyang , Wang Yuankun , Bu Huaitian , Li Mingtao , Zhang Yanfeng , Gao Guoxin , Ding Shujiang
Published: December 2019

The mechanical properties and electrochemical stability of a PEO based composite solid polymer electrolyte are enhanced by adding MnO2 nanosheets.
A 3D hierarchical dual-metal–organic framework heterostructure up-regulating the pre-concentration effect for ultrasensitive fluorescence detection of tetracycline antibiotics
Authors: Li Chunhua , Yang Weixia , Zhang Xiaoshuo , Han Yong , Tang Wenzhi , Yue Tianli , Li Zhonghong
Published: December 2019

This work demonstrates a 3D hierarchical Al-MOF@Mo/Zn-MOF heterostructure for exceptionally high performance detection of tetracycline antibiotics in environmental and food samples.
Hypochlorous acid-mediated modification of proteins and its consequences
Authors: Hawkins Clare L.
Published: December 2019

Myeloperoxidase (MPO) is a mammalian heme peroxidase released by activated immune cells, which forms chemical oxidants, including hypochlorous acid (HOCl), to kill bacteria and other invading pathogens. In addition to this important role in the innate immune system, there is significant evidence from numerous chronic inflammatory pathologies for the elevated production of HOCl and associated oxidative modification of proteins and damage to host tissue. Proteins are major targets for HOCl in biological systems, owing to their abundance and the high reactivity of several amino acid side-chains with this oxidant. As such, there is significant interest in understanding the molecular mechanisms involved in HOCl-mediated protein damage and defining the consequences of these reactions. Exposure of proteins to HOCl results in a wide range of oxidative modifications and the formation of chlorinated products, which alter protein structure and enzyme activity, and impact the function of biological systems. This review describes the reactivity of HOCl with proteins, including the specific pathways involved in side-chain modification, backbone fragmentation and aggregation, and outlines examples of some of the biological consequences of these reactions, particularly in relation to the development of chronic inflammatory disease.
How It Works in the Real World: Helping Students Navigate Clinical Placements
Authors: Bice Ed M. , Smith Pamela A.
Published: December 2019

Purpose

This article discusses current issues found in external clinical placements and their possible causes, and this offers practical solutions for assisting students to benefit from their experiences. In order to obtain a Certificate of Clinical Competence from the American Speech-Language-Hearing Association, students must obtain a required number of patient contact hours. Many of these experiences are supervised by a mentor outside of the university setting. This provides opportunity for the student to be exposed to various clinical philosophies. It also opens the possibility that the student will be exposed to practices that are not based in sound theory or evidence.

Conclusion

Preparing students to assess and manage clinical placements is vital to their success. Several suggestions for encouraging and facilitating productive clinical conversations between mentor and mentee are proposed.
WKS‐type distributionally robust optimisation for optimal sub‐hourly look‐ahead economic dispatch
Authors: Liu Yang , Chen Xianbang , Li Bin , Li Huaqiang , Ye Yanli
Published: December 2019

Renewable energy sources, particularly wind power, are being increasingly deployed in power systems to reduce environmental contamination. However, the uncertainty of wind power significantly influences power system economy. Therefore, this study presents Wiesemann–Kuhn–Sim (WKS)‐type distributionally robust optimisation for performing an optimal two‐stage sub‐hourly look‐ahead economic dispatch considering uncertain wind power. The dispatch considers the scheduling of thermal generators, wind power generators, and fast‐response resources. The optimisation aims at minimising the expected total operational cost, including the costs of generation, generation shedding, and wind power curtailment. The hourly stage determines the thermal generation that can withstand the worst‐case wind power distribution. The sub‐hourly stage schedules the fast‐response operations to correct the hourly dispatch. To characterise the uncertainty, a novel WKS‐format ambiguity set that can obtain wind power distribution from historical data is constructed using the lifting theorem. Based on the ambiguity set and linear decision rule, a general lemma is employed to convert the model into a tractable conic optimisation that can be directly solved. Experimental results demonstrate the effectiveness of the presented approach compared to adjustable robust optimisation and sample‐based stochastic optimisation.
GNSS intermediate spoofing detection via dual‐peak in frequency domain and relative velocity residuals
Authors: Tu Jiaxun , Zhan Xingqun , Chen Maolin , Gao Han , Chen Yuankang
Published: December 2019

GNSS intermediate spoofing is a big threat to GNSS‐dependent services because of its strong concealment. When the carrier Doppler of the spoofing signal is not locked to that of the authentic signal, such spoofing will result in the presence of dual‐peak in the signal spectrum. In the absence of interference, there should be no dual‐peak. In the multipath scenario, dual‐peak may exist, but the number of dual‐peaks and relative velocity residual magnitudes of dual‐peak signals are different from those in the spoofing scenario. Therefore, an intermediate spoofing detection technique based on dual‐peak in frequency domain and relative velocity residuals is proposed in this study, which can not only detect spoofing but also distinguish spoofing scenario from the multipath scenario. Fast Fourier transform based methods are used to detect the dual‐peak and extract the Doppler difference of the dual‐peak, and the relative velocity residual calculation based on Doppler differences is derived. The performance of this approach is evaluated both analytically and experimentally: simulation results show spoofing false alarm probability in the multipath scenario is small, which indicates that spoofing scenario and multipath scenario can be well distinguished; and the effectiveness is verified based on the Texas Spoofing Test Battery (TEXBAT).
Main lobe jamming suppression via blind source separation sparse signal recovery with subarray configuration
Authors: Ge Mengmeng , Cui Guolong , Yu Xianxiang , Kong Lingjiang
Published: December 2019

The performance of the modern radar systems will degrade significantly in the presence of main lobe jamming. In this study, a new methodology is introduced to suppress multiple main lobe jammings while accomplishing the directions of arrival (DOAs) estimation of the multiple targets. Specifically, the signal model of a specific subarray configuration accounting for jamming and target signals is developed. Then, blind source separation method is utilised to separate the target and jamming signals in each subarray. Furthermore, the separated target signals of all subarrays are jointly imposed to estimate DOAs of targets through resorting to sparse signal recovery approach. Finally, numerical simulations are provided to assess the performance of the proposed algorithm exhibiting the favourable capabilities in terms of the strong main lobe jamming suppression and the DOAs estimation of multiple targets.
PDMS‐based hot embossing method of fabricating SU‐8 photoresist conical nozzle for inkjet print‐head
Authors: Yan Shixia , Wang Xing , Li Kehong , Wang Fengwei , Guo Ran , Zou Helin
Published: December 2019

This work reports a PDMS‐based hot embossing technique. The proposed method enables rapid, low‐cost and mass‐produced fabrication of SU‐8 photoresist conical nozzle for inkjet print‐head with soft PDMS moulds. The hydrophobic time for SU‐8 master mould treated by trimethyldichlorosilane (TMCS) was determined. And the optimised thickness of SU‐8 photoresist before hot embossing was 58.5 ± 1.55 μm corresponding to 3750 r/min of spin coating speed. The imprinting parameters were investigated. The highest replication precision was obtained in the embossed SU‐8 conical nozzle processed by an embossing pressure of 2.57 MPa, an embossing temperature of 80°C, and an embossing time of 6 min. Finally, this work presents the fabrication of the SU‐8 conical nozzle plate with the large aperture of 40.01 ± 1.24 μm, small aperture of 27.12 ± 1.07 μm, and the nozzle height of 50 ± 1.26 μm.
X-ray spectral and flux variability of the microquasar GRS 1758−258 on timescales from weeks to years
Authors: Hirsch Maria , Pottschmidt Katja , Smith David M. , Bodaghee Arash , Cadolle Bel Marion , Grinberg Victoria , Hell Natalie , Krauß Felicia , Kreykenbohm Ingo , Lohfink Anne , Nowak Michael A. , Rodrigues Bárbara H. , Soria Roberto , Tomsick John A. , Wilms Jörn
Published: December 2019

We present the spectral and timing evolution of the persistent black hole X-ray binary GRS 1758−258 based on almost 12 years of observations using the Rossi X-ray Timing Explorer Proportional Counter Array. While the source was predominantly found in the hard state during this time, it entered the thermally dominated soft state seven times. In the soft state GRS 1758−258 shows a strong decline in flux above 3 keV rather than the pivoting flux around 10 keV more commonly shown by black hole transients. In its 3–20 keV hardness intensity diagram, GRS 1758−258 shows a hysteresis of hard and soft state fluxes typical for transient sources in outburst. The RXTE-PCA and RXTE-ASM long-term light curves do not show any orbital modulations in the range of 2–30 d. However, in the dynamic power spectra significant peaks drift between 18.47 and 18.04 d for the PCA data, while less significant signatures between 19 d and 20 d are seen for the ASM data as well as for the Swift/BAT data. We discuss different models for the hysteresis behavior during state transitions as well as possibilities for the origin of the long term variation in the context of a warped accretion disk.
How planets grow by pebble accretion
Authors: Brouwers M. G. , Ormel C. W.
Published: December 2019

Context. Proto-planets embedded in their natal disks acquire hot envelopes as they grow and accrete solids. This ensures that the material they accrete – pebbles, as well as (small) planetesimals – will vaporize to enrich their atmospheres. Enrichment modifies an envelope’s structure and significantly alters its further evolution.

Aims. Our aim is to describe the formation of planets with polluted envelopes from the moment that impactors begin to sublimate to beyond the disk’s eventual dissipation.

Methods. We constructed an analytical interior structure model, characterized by a hot and uniformly mixed high-Z vapor layer surrounding the core, located below the usual unpolluted radiative-convective regions. Our model assumes an ideal equation of state and focuses on identifying trends rather than precise calculations. The expressions we derived are applicable to all single-species pollutants, but we used SiO2 to visualize our results.

Results. The evolution of planets with uniformly mixed polluted envelopes follows four potential phases. Initially, the central core grows directly through impacts and rainout until the envelope becomes hot enough to vaporize and absorb all incoming solids. We find that a planet reaches runaway accretion when the sum of its core and vapor mass exceeds a value that we refer to as the critical metal mass – a criterion that supersedes the traditional critical core mass. The critical metal mass scales positively with both the pollutant’s evaporation temperature and with the planet’s core mass. Hence, planets at shorter orbital separations require the accretion of more solids to reach runaway as they accrete less volatile materials. If the solids accretion rate dries up, we identify the decline of the mean molecular weight – dilution – as a mechanism to limit gas accretion during a polluted planet’s embedded cooling phase. When the disk ultimately dissipates, the envelope’s inner temperature declines and its vapor eventually rains out, augmenting the mass of the core. The energy release that accompanies this does not result in significant mass-loss, as it only occurs after the planet has substantially contracted.
Metal-poor nuclear star clusters in two dwarf galaxies near Centaurus A suggesting formation from the in-spiraling of globular clusters
Authors: Fahrion Katja , Müller Oliver , Rejkuba Marina , Hilker Michael , Lyubenova Mariya , van de Ven Glenn , Georgiev Iskren Y. , Lelli Federico , Pawlowski Marcel S. , Jerjen Helmut
Published: December 2019

Studies of nucleated dwarf galaxies can constrain the scenarios for the formation and evolution of nuclear star clusters (NSC) in low-mass galaxies and give us insights on the origin of ultra compact dwarf galaxies (UCDs). We report the discovery of a NSC in the dwarf galaxy KKs58 and investigate its properties together with those of another NSC in KK197. Both NSCs are hosted by dwarf elliptical galaxies of the Centaurus group. Combining ESO VLT MUSE data with photometry from VLT FORS2, CTIO Blanco DECam, and HST ACS, as well as high-resolution spectroscopy from VLT UVES, we analyse the photometric, kinematic and stellar population properties of the NSCs and their host galaxies. We confirm membership of the NSCs based on their radial velocities and location close to the galaxy centres. We also confirm the membership of two globular clusters (GCs) and detect oblate rotation in the main body of KK197. Based on high signal-to-noise spectra taken with MUSE of the NSCs of both KKs58 and KK197 we measure low metallicities, [Fe/H] = −1.75 ± 0.06 dex and [Fe/H] = −1.84 ± 0.05 dex, and stellar masses of 7.3 × 105 M⊙ and 1.0 × 106 M⊙, respectively. Both NSCs are more metal-poor than their hosts that have metallicities of −1.35 ± 0.23 dex (KKs58) and −0.84 ± 0.12 dex (KK197). This can be interpreted as NSC formation via the in-spiral of GCs. The masses, sizes and metallicities of the two NSCs place them among other NSCs, but also among the known UCDs of the Centaurus group. This indicates that NSCs might constitute the progenitors of a part of the low-mass UCDs, although their properties are almost indistinguishable from typical GCs.
Should We Make More Bone or Not, As Told by Kisspeptin Neurons in the Arcuate Nucleus
Authors: Herber Candice B. , Ingraham Holly A.
Published: December 2019

Since its initial discovery in 2002, the neuropeptide Kisspeptin (Kiss1) has been anointed as the master regulator controlling the onset of puberty in males and females. Over the last several years, multiple groups found that Kiss1 signaling is mediated by the 7TM surface receptor GPCR54. Kiss1 mRNA is highly enriched in the basal medial and lateral subregions of the arcuate nucleus (ARC) in the medial basal hypothalamus. Thus, Kiss1ARC neurons reside in a unique anatomical location ideal for sensing and responding to circulating steroid hormones as well as nutrients. Kiss1 expression is highly responsive to fluctuations of the gonadal hormone, estrogen, with nearly 90% of Kiss1ARC neurons expressing the nuclear hormone estrogen receptor alpha (ERa). Here we review recent research that extends the function of Kiss1ARC neurons beyond the regulation of puberty and highlight their emerging, novel roles in controlling energy allocation, behavioral outputs, and sex-dependent bone remodeling in females. Indeed, some of these previously unknown functions for Kiss1 neurons are quite striking as exemplified by the remarkable increase in bone mass after manipulating estrogen signaling in Kiss1ARC neurons. Taken together, we suggest that Kiss1ARC neurons are highly sensitive to nutritional and hormonal cues that dictate energy utilization and reproduction.
Back-to-back Schottky junction photodetectors based on CVD grown CsPbBr3 microcrystalline striped films
Authors: Cui Di , Tian Cancan , Wang Yunpeng , Wang Fei , Yang Zhe , Mei Jingjing , Liu Hongzhen , Zhao Dongxu
Published: December 2019

In recent years, a new type of lead halide perovskite has attracted a lot of attention for next-generation photodetectors (PDs) with high responsivity, good detectivity, and fast photoresponse speed. Specifically, cesium based all-organic perovskites exhibit better photostability and therefore have achieved increasing success in PDs recently. For reducing the leak current and increasing the response speed of photoconductive PDs, back-to-back Schottky junction PD is designed and fabricated through a direct growth approach of CsPbBr3 microcrystal (MC) films on indium tin oxide (ITO) electrodes by the chemical vapor deposition (CVD) method. Due to the enhanced Schottky barrier height and threshold voltage between CsPbBr3 and ITO electrodes, the PD exhibits the on/off ratio of up to 104, peak responsivity of 3.9 AW−1, detectivity of 3.8 × 1012, and fast response speed of 0.22 ms (rise time) and 0.45 ms (decay time). In addition, the stability of PD is also enhanced by the high crystal quality of CVD grown CsPbBr3 MCs.
Ellagitannins from Punica granatum leaves suppress microsomal prostaglandin E synthase-1 expression and induce lung cancer cells to undergo apoptosis
Authors: Toda Keisuke , Ueyama Mai , Tanaka Shomu , Tsukayama Izumi , Mega Takuto , Konoike Yuka , Tamenobu Asako , Bastian Februadi , Akai Iria , Ito Hideyuki , Kawakami Yuki , Takahashi Yoshitaka , Suzuki-Yamamoto Toshiko
Published: December 2019

Prostaglandin E2 (PGE2), which is a potent pro-inflammatory lipid mediator, is biosynthesized from arachidonic acid by cyclooxygenase-2 (COX-2) and microsomal PGE synthase-1 (mPGES-1). Non-steroidal anti-inflammatory drugs (NSAIDs) are used clinically as COX inhibitors, but they have gastrointestinal and cardiovascular side-effects. Thus, the terminal enzyme mPGES-1 holds promise as the next therapeutic target. In this study, we found that the ellagitannins granatin A and granatin B isolated from pomegranate leaves, and geraniin, which is their structural analog, selectively suppressed mPGES-1 expression without affecting COX-2 in non-small cell lung carcinoma A549 cells. The ellagitannins also down-regulated tumor necrosis factor α, inducible nitric oxide synthase, and anti-apoptotic factor B-cell chronic lymphocytic leukemia/lymphoma 2, and induced A549 cells to undergo apoptosis. These findings indicate that the ellagitannins have anti-inflammatory and anti-carcinogenic effects, due to their specific suppression of mPGES-1.

Abbreviations: Bcl-2: B-cell chronic lymphocytic leukemia/lymphoma 2; COX: cyclooxygenase; CRE: cAMP response element; DHHDP: dehydrohexahydroxydiphenoyl; Et2O: diethyl ether; EtOAc: ethyl acetate; GAPDH: glyceraldehyde 3-phosphate dehydrogenase; iNOS: inducible nitric oxide synthase; mPGES-1: microsomal prostaglandin E synthase-1; n-BuOH: water-saturated n-butanol; NSAIDs: non-steroidal anti-inflammatory drugs; NF-κB: nuclear factor-κB; PG: prostaglandin; TNF: tumor necrosis factor; TUNEL: terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling
Numerical simulations of strong-field processes in momentum space*
Authors: Xu Yan , Bian Xue-Bin
Published: December 2019

The time-dependent Schrödinger equation (TDSE) is usually treated in the real space in the textbook. However, it makes the numerical simulations of strong-field processes difficult due to the wide dispersion and fast oscillation of the electron wave packets under the interaction of intense laser fields. Here we demonstrate that the TDSE can be efficiently solved in the momentum space. The high-order harmonic generation and above-threshold ionization spectra obtained by numerical solutions of TDSE in momentum space agree well with previous studies in real space, but significantly reducing the computation cost.
Water quality simulation for rehabilitation of a eutrophic lake in Selangor, Malaysia
Authors: Koh H L , Tan W K , Teh S Y , Tay C J
Published: December 2019

More than 50 % of lakes worldwide, including 60 % in Malaysia, are contaminated by eutrophication due to excessive nutrient inputs. These nutrients include phosphorus and nitrogen derived from agriculture, industry and domestic wastes. Eutrophication is an undesirable lake condition characterized by turbid water and dominated by abundant growth of algae, resulting in suppressed macrophytes and in reduced ecosystem services. Healthy lakes provide ecosystem services that have been valued to be worth billions to the Malaysian Gross Domestic Production annually. Rehabilitation of eutrophic lakes located in urban areas is therefore urgently needed. A recreational lake located in Selangor Malaysia has shown persistent signs of eutrophication with chlorophyll-a level fluctuating between 10 and 25 µg/L. Left untreated, the lake water quality will deteriorate further, potentially inducing a regime shift to hypereutrophic condition, caused by intense interaction between water column phosphorus and sediment phosphorus. Based upon water and sediment quality data compiled over the last eight years, this paper presents analysis and model simulations for implementation of a sustainable program for controlling eutrophication using low cost technology.
Assessing phytoplankton distribution and water quality in constructed wetlands during dry and wet periods: A Case Study in USM Engineering Campus
Authors: Shaharuddin S , Zakaria NA , Ghani Ab , Wan Maznah WO
Published: December 2019

Constructed wetlands (CW) are built to improve water quality while serving as an alternative sustainable habitat for aquatic life. In Malaysia, CWs are designed according to the guideline for Urban Stormwater Management Manual for Malaysia (MSMA 2nd Edition) 2012. This study shall evaluate the performance of constructed wetland design as stipulated by MSMA through assessment of water quality and phytoplankton growth, which acts as a biodiversity indicator. A 5-month sampling period with phytoplankton abundance in a constructed wetland was correlated with the selected water quality index (WQI) parameters comprising dissolved oxygen (DO), ammoniacal oxygen (AN), chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solid (TSS), and pH. The constructed wetland consists of three main zones, namely the forebay, macrophytes and micropool zones. The highest WQI value was obtained from the micropool zone with a range of 78.98-85.45 (82.71±3.35) while the lowest WQI value was collected from the macrophytes zone with a range of 68.13-77.96 (73.25±3.42). A total of 15 phytoplankton species from 5 different algal phyla were identified in the constructed wetland. Phytoplankton distribution was high in the macrophytes zone (521 cell m-3) during dry season due to high nutrient concentration as opposed to the other zones. The phytoplankton distribution was found to be closely associated with DO, AN, TSS and total phosphorus. At the same time, the macrophyte zone design also affects the distribution of phytoplankton.
Controlling the concentration of gold nanorods during their dielectrophoresis-assisted deposition
Authors: Ali Khan Ghazanfar , Hassan Muhammad Umair , Manzoor Umair , Bhatti Arshad Saleem , Ahmed Waqqar
Published: December 2019

Gold nanorods (AuNRs) have attracted great interest due to their excellent plasmonic properties which makes them a promising candidate for many applications. However, most of the applications require control over the position and concentration of nanorods (NRs) by processes that are fast, reliable and scalable. The focus of this work is to study the effects of variation of various parameters, such as applied voltage, frequency, solvents and drying time on the concentration of dielectrophoresis (DEP) -assisted deposition of AuNRs. We have seen that the concentration of AuNRs within the electrodes can be considerably increased by increasing the applied voltage and deposition time, and by choosing a more volatile solvent. Furthermore, the applied frequency also strongly influences the deposition of AuNRs. At lower frequencies, the electro-osmotic flows drag AuNRs to the top of electrodes, while at higher frequencies NRs are deposited close to the electrode edge where the electric field and the field gradient are maximum. We have also carried out simulations using the finite element method to generate the electric field patterns for coplanar electrodes. Our results provide insight into ways in which the concentration of AuNRs can be controlled during DEP-assisted deposition.
Study on the interfacial bonding mechanism of Al/Mg gradient material
Authors: Long Luping , Peng Yingbiao , Sun Bin , Liu Wensheng
Published: December 2019

Ti/Al/Mg impedance-graded material sheet is an alternative to the homogeneous single-layer sheets, which has been presented to improve shielding performance through the high efficient absorption and dissipation of fragment kinetic energy. Nevertheless, one limitation of the Ti/Al/Mg gradient material is associated with the weak Al/Mg interface. The purpose of this study is to investigation the interfacial bonding mechanism of Al/Mg gradient material interface. Microstructure characteristics at the Al/Mg interface have been investigated. It shows that an isolated island structure preferentially generates at the crystal defect as a consequence of interdiffusion, which is composed of Al3Mg2 and Al12Mg17. Then such intermetallic compounds (IMCs) grow to continuous layers with distinct convex. Finally, the interface is fully transformed into flat. A theoretical analysis and calculation have been carried out to explain the thermodynamically feasibility of IMCs. The evolution mechanism of voids at the interface is also discussed. Fractographic analysis performed on selected specimens shows typical brittle cleavage fracture characteristics, and detailed analyses reveal that the fracture failure is associated with brittle IMCs.
Microstructure and mechanical properties variation with Ni content in Al0.8CoCr0.6Fe0.7Nix (x = 1.1, 1.5, 1.8, 2.0) eutectic high-entropy alloy system
Authors: Ma Lili , Wang Jianing , Jin Peipeng
Published: December 2019

Eutectic high-entropy alloys have drawn extensive attention because of their remarkable performance on the combination of strength and plasticity. In this study, a new Al0.8CoCr0.6Fe0.7Ni
x
(x = 1.1, 1.5, 1.8, 2.0) eutectic high-entropy alloy system was designed; the microstructure and mechanical properties variation of alloys with the change in Ni content were investigated detailly. All of four alloys exhibited FCC+B2 dual-phase structure, while the volume fraction of FCC phase increased from 44% to 90% with an increase in Ni content. Meanwhile, the microstructure of alloys variated from an irregular dendrite morphology to a lamellar eutectic microstructure, and finally to a hypoeutectic microstructure composed by primary FCC phase and the rest eutectic mixture. Accordingly, the yield strength of alloys decreased from 625 MPa to 415 MPa, and the total elongation increased from 7.4% to 21.8%. The Al0.8CoCr0.6Fe0.7Ni1.5 alloy displayed a nano-scale lamellar eutectic microstructure and exhibited a relatively good combination of strength and plasticity in these four alloys, with a yield strength of 490 MPa, a ultimate strength of 980 MPa and a total elongation of 14.8%. The findings could contribute to explore HEAs with good combination of strength and plasticity and promote the applications of high-entropy alloys in industrial fields.