bluuebunny/crossref_metadata_2025 huggingface dataset:
Transcriptomic analysis of the mouse retina after acute and chronic normobaric and hypobaric hypoxia
Authors: Ebner L. J. A. , Samardzija M. , Storti F. , Todorova V. , Karademir D. , Behr J. , Simpson F. , Thiersch M. , Grimm C.
Published: August 2021

Oxygen delivery to the retinal pigment epithelium and the outer retina is essential for metabolism, function, and survival of photoreceptors. Chronically reduced oxygen supply leads to retinal pathologies in patients and causes age-dependent retinal degeneration in mice. Hypoxia can result from decreased levels of inspired oxygen (normobaric hypoxia) or reduced barometric pressure (hypobaric hypoxia). Since the response of retinal cells to chronic normobaric or hypobaric hypoxia is mostly unknown, we examined the effect of six hypoxic conditions on the retinal transcriptome and photoreceptor morphology. Mice were exposed to short- and long-term normobaric hypoxia at 400 m or hypobaric hypoxia at 3450 m above sea level. Longitudinal studies over 11 weeks in normobaric hypoxia revealed four classes of genes that adapted differentially to the hypoxic condition. Seventeen genes were specifically regulated in hypobaric hypoxia and may affect the structural integrity of the retina, resulting in the shortening of photoreceptor segment length detected in various hypoxic groups. This study shows that retinal cells have the capacity to adapt to long-term hypoxia and that consequences of hypobaric hypoxia differ from those of normobaric hypoxia. Our datasets can be used as references to validate and compare retinal disease models associated with hypoxia.
Predation risk is a function of seasonality rather than habitat complexity in a tropical semiarid forest
Authors: Ferreira Anthony Santana , Faria Renato Gomes
Published: August 2021

Predator–prey dynamics are some of the most important species’ interactions in the natural structuring of communities, and are among the more complex ecological processes studied by ecologists. We measured predation risk using artificial lizard replicas to test two competing hypotheses regarding predation pressure in semi-arid environments: (1) predation risk is dependent on the habitat structural complexity; and (2) predation risk is dependent on seasonality. We placed 960 lizard replicas along three sites with different physical structures and in both dry and rainy seasons for seven consecutive days in a caatinga area in northeastern Brazil at Grota do Angico Natural Monument (GANM). Birds were responsible for the majority of attacks and more frequently on artificial lizards placed in trees. Attacks focused on the most vulnerable areas of the body (head and torso), proving that were perceived by predators as true prey items. We found that predation risk is not dependent on the habitat structural complexity, but rather dependent on the caatinga seasonality, with the overall attack rate being 19% higher in the dry season. Our study suggests that potential predation risk is highly context-dependent and that seasonality consistently drives of trophic interactions strength in the caatinga, an important ecological finding that could contribute to better understanding the complex evolution of predator–prey interactions within communities of animals living in different habitats.
Determination of UV-327 and its metabolites in human urine using dispersive liquid-liquid microextraction and gas chromatography-tandem mass spectrometry
Authors: Fischer Corinna , Göen Thomas
Published: August 2021

A method is presented for the extraction of the UV stabilizer UV-327 and its metabolites from urine with acetonitrile (disperser solvent) and chloroform (extraction solvent), followed by instrumental analysis of the trimethylsilylated analytes.
Dual-excitation and dual-emission carbon dots for Fe3+ detection, temperature sensing, and lysosome targeting
Authors: Li Xiaofeng , Bao Yuejing , Dong Xiaorui , Shi Lihong , Shuang Shaomin
Published: August 2021

Dual-excitation and dual-emission carbon dots (CDs) have been prepared by simple one-step hydrothermal treatment of p-phenylenediamine and 5-aminosalicylic acid.
Flexible electrochemical aptasensor for cortisol detection in human sweat
Authors: Mugo Samuel M. , Alberkant Jonathan , Bernstein Nina , Zenkina Olena V.
Published: August 2021

An inexpensive flexible PDMS@CNC/CNT@aptamer sensor for facile detection of cortisol in human sweat with capacity for use as wearable device.
Electrospray deposition for single nanoparticle studies
Authors: Jagdale Gargi S. , Choi Myung-Hoon , Siepser Natasha P. , Jeong Soojin , Wang Yi , Skalla Rebecca X. , Huang Kaixiang , Ye Xingchen , Baker Lane A.
Published: August 2021

Electrospray deposition provides a suitable route to samples for single entity electrochemical (SEE) studies. We detail and parameterize the methods relevant to SEE sample preparation.
Plasmonic enhanced enzyme activity by catalytic cascade induced mutual benefit tumor starvation/immune/photothermal therapy
Authors: Cheng Xin , Hao Zining , Chu Shuzhen , Zhang Tiantian , Cong Cong , Liu Lanxiang , Zhang Weidong , Gu Jianmin , Ni Song , Wang Desong , Gao Dawei
Published: August 2021

Single tumor starvation therapy can activate other signaling pathways in tumor cells and easily induce tumor cell metastasis.
Improvement of thermal stability and photoluminescence in Mg2Y2Al2Si2O12:Ce3+ by the cation substitution of Ca2+, Sr2+ and Ba2+ ions
Authors: Tao Chunjing , Li Panlai , Li Qinshan , Zhang Nan , Wang Dawei , Zhao Jinxin , Yang Zhiping , Wang Zhijun
Published: August 2021

The luminescence of Ce3+ in Mg2Y2Al2Si2O12 (MgYAlSiO6) can be controlled by substituting with Ca2+, Sr2+, and Ba2+ ions.
Solid-state synthesis of single-phase nickel monophosphosulfide for the oxygen evolution reaction
Authors: Wang Miao , Saad Ali , Li Xiaoguang , Peng Tao , Zhang Qi-Tao , Kumar Mohan , Zhao Wei
Published: August 2021

A novel ternary NiPS compound with superior electrocatalytic OER activity fabricated via a simple solid-state route in alkaline media.
Oligopeptides from Jinhua ham prevent alcohol-induced liver damage by regulating intestinal homeostasis and oxidative stress in mice
Authors: Nie Wen , Du Ye-ye , Xu Fei-ran , Zhou Kai , Wang Zhao-ming , Al-Dalali Sam , Wang Ying , Li Xiao-min , Ma Yun-hao , Xie Yong , Zhou Hui , Xu Bao-cai
Published: August 2021

Lys-Arg-Gln-Lys-Tyr-Asp bioactive peptide in JHP prevent ALD by regulating gut microbiota, upregulating the expression of the NRF2/HO-1 antioxidant defense system and reducing oxidative stress injury in liver cells.
Effect of Lactiplantibacillus plantarum HM-22 on immunoregulation and intestinal microbiota in α-lactalbumin-induced allergic mice
Authors: Jiang Shujuan , Hou Yaqi , Meng Lingying , Pu Xueli , Zhu Xuemei , Tuo Yanfeng , Qian Fang , Mu Guangqing
Published: August 2021

This work revealed the protective effect of L. plantarum HM-22 in α-LA-induced allergic mice, demonstrated by the alleviation of allergic symptoms, colon inflammation and intestinal microbiota changes.
The detection of Al3+ and Cu2+ ions using isonicotinohydrazide-based chemosensors and their application to live-cell imaging
Authors: Song In-ho , Torawane Pritam , Lee Jung-Seop , Warkad Shrikant Dashrath , Borase Amulrao , Sahoo Suban K. , Nimse Satish Balasaheb , Kuwar Anil
Published: August 2021

The quick response, easy-synthesis, and high sensitivity make receptor 3 an ideal sensor for detecting Al3+ ions in a semi-aqueous medium and living cells.
Tuneable chemistry at the interface and self-healing towards improving structural properties of carbon fiber laminates: a critical review
Authors: Banerjee Poulami , Raj Rishi , Kumar S. , Bose Suryasarathi
Published: August 2021

Interfacial modification of CFRE laminates and the emerging domain of strength recovery via self-healing.
The biology and total syntheses of bisbenzylisoquinoline alkaloids
Authors: Nguyen Viviene K. , Kou Kevin. G. M.
Published: August 2021

This mini-review provides a concise overview of the biosynthetic pathway and pharmacology of bisbenzylisoquinoline alkaloid (bisBIA) natural products.
Unexpected formation of poly-functionalized fulvenes by the reaction of a tetraaryl[5]cumulene with iodine
Authors: Hoshi Keita , Yasuda Masashi , Nakamura Takumi , Yoshida Yasushi , Ueta Shoko , Minagawa Keiji , Kawamura Yasuhiko , Imada Yasushi , Yagishita Fumitoshi
Published: August 2021

The reaction of tetrakis(p-methoxyphenyl)[5]cumulene with iodine afforded the iodinated fulvene scaffold via iodocyclization followed by unexpected migration of a terminal aryl ring under ambient condition.
A mild and practical method for deprotection of aryl methyl/benzyl/allyl ethers with HPPh2 and tBuOK
Authors: Pan Wenjing , Li Chenchen , Zhu Haoyin , Li Fangfang , Li Tao , Zhao Wanxiang
Published: August 2021

Aryl methyl/benzyl/allyl ethers with various functional groups reacted smoothly to afford deprotected products in high yields, and further investigation showed that deallylation is easier than debenzylation and demethylation.
Recent progress in the radical α-C(sp3)–H functionalization of ketones
Authors: Li Jiao-Zhe , Zhang Wei-Kang , Ge Guo-Ping , Zheng Hongxing , Wei Wen-Ting
Published: August 2021

We outline the recent progress in the development of methods that enable the radical α-C(sp3)–H functionalization of ketones, with an emphasis on radical initiation systems and possible mechanisms.
Slightly congested amino terminal dendrimers. The synthesis of amide-based stable structures on a large scale
Authors: Morgado Anjara , Najera Francisco , Lagunas Anna , Samitier Josep , Vida Yolanda , Perez-Inestrosa Ezequiel
Published: August 2021

Preparation of a new family of stable and aqueous soluble high-generation aliphatic polyamide amino terminal dendrimers. Promising scaffolds for applications where the combination of stability, multivalence and efficient conjugation is required.
Nitrogen-rich tricyclic-based energetic materials
Authors: Tang Jie , Yang Hongwei , Cui Yong , Cheng Guangbin
Published: August 2021

A systematic introduction to the developments in heterocyclic high energy density materials (HEDMs) with various explosive units in the form of tricyclic-based oxadiazole.
A recent overview of porphyrin-based π-extended small molecules as donors and acceptors for high-performance organic solar cells
Authors: Piradi Venkatesh , Yan Feng , Zhu Xunjin , Wong Wai-Yeung
Published: August 2021

Structural development of porphyrin-based small molecules as electron donors and electron acceptors leads to optimal photovoltaic performances, with PCEs of over 12% and 9.6%, respectively, in bulk-heterojunction organic solar cells.
Structural fine-tuning of zwitterionic salts for the discovery of LCST-type thermoresponsive materials
Authors: Chu Yen-Ho , Chen Chien-Yuan
Published: August 2021

In our current work, we discovered N-triflimide (NTf)-based zwitterionic ionic liquids (ZILs) exhibiting LCST phase transitions in water and showed an ability to further fine tune their structure to afford N-pentafluoroethylsulfonimide (NPf)-based ZILs displaying Tc values attractive for potential applications.
Biomass-derived O, N-codoped hierarchically porous carbon prepared by black fungus and Hericium erinaceus for high performance supercapacitor
Authors: Zhong Xinxian , Mao Quanyuan , Li Zesheng , Wu Zhigao , Xie Yatao , Li Shu-Hui , Liang Guichao , Wang Hongqiang
Published: August 2021

Biomass-derived heteroatom self-doped porous carbons are expected to become ideal active materials for high performance supercapacitor.
A self-matting waterborne polyurethane coating with admirable abrasion-resistance
Authors: Lin Zhixian , Sun Zhe , Xu Chengping , Zhang Aiqin , Xiang Jun , Fan Haojun
Published: August 2021

Due to the paradox between abrasion-resistance and extinction, the development of a self-matting waterborne polyurethane (SMWPU) coating accompanied by excellent abrasion-resistance is still a challenge.
α-Oxygenation ofN-aryl/alkyl heterocyclic compoundsviaruthenium photocatalysis
Authors: Kumar Inder , Thakur Ankita , Manisha  , Sharma Upendra
Published: August 2021

We herein report ruthenium(iii) photocatalyzed oxidation ofN-aryl tertiary amines to the corresponding amides.
Engineering proteinaceous colloidosomes as enzyme carriers for efficient and recyclable Pickering interfacial biocatalysis
Authors: Jiang Hang , Hu Xiaofeng , Li Yunxing , Yang Cheng , Ngai To
Published: August 2021

Engineering proteinaceous colloidosomes with magnetic-responsiveness are designed as both enzyme carrier and emulsifier, achieving a breakthrough in protein-based w/o Pickering interfacial biocatalysis.
Two-step anti-cooperative self-assembly process into defined π-stacked dye oligomers: insights into aggregation-induced enhanced emission
Authors: Vonhausen Yvonne , Lohr Andreas , Stolte Matthias , Würthner Frank
Published: August 2021

The self-assembly of a dipolar merocyanine into preferred dimers and small-sized chiral aggregates leads to enhanced emission due to a reduced non-radiative rate as well as amplified circular polarized luminescence.
Excellent ultraviolet optical limiting properties of 2D chromium nanosheets
Authors: Yuan Junjie , Xin Yi , Li Zhao , Xing Fei , Zhang Fang
Published: August 2021

Successfully fabricated 2D chromium nanosheets through the liquid phase exfoliation method and investigated the broadband nonlinear optical properties employed the open aperture Z-scan technique.
FeCO3 as a novel precursor for controllable synthesis of monodisperse iron oxide nanoparticles via solution thermal decomposition
Authors: Wang Guorong , Cui Mengyao , Qiu Ying , Miao Yuqing , Ma Huijun , Zhang Huan , Zhang Yifan , Liu Xiaoli , Yi Jiabao , Peng Mingli , Fan Haiming
Published: August 2021

Thermal decomposition in solution is the most effective approach for achieving highly monodisperse iron oxide nanoparticles (IONPs). However, a simple, economical, and environment‐friendly iron precursor with high iron content remains in great demand. Although siderite (FeCO3) has been reported to produce iron oxide particles via calcination, it is difficult to control the shapes of the obtained particles compared to those obtained by solution methods. Herein, FeCO3 was employed as a precursor in solution thermal decomposition to prepare monodisperse IONPs and investigated the influence of reaction conditions on the particle size, including the concentration of oleic acid, concentration of the precursor, and the reaction temperature. The seed‐mediated growth method with FeCO3 as a precursor was also studied to extend the scope of particle size. The experimental results demonstrate that high‐quality IONPs can be synthesized in solution via FeCO3 thermal decomposition. The particle diameter was tuned between 3 and 20 nm by varying the reaction conditions, and by seed‐mediated growth. FeCO3 is thus a readily available, economical, environment‐friendly precursor with high iron content, which is a novel candidate for the synthesis of IONPs.
Thermal radio absorption as a tracer of the interaction of SNRs with their environments
Authors: Castelletti G. , Supan L. , Peters W. M. , Kassim N. E.
Published: August 2021

We present new images and continuum spectral analysis for 14 resolved Galactic supernova remnants (SNRs) selected from the 74 MHz Very Large Array Low-Frequency Sky Survey Redux (VLSSr). We combine new integrated measurements from the VLSSr with, when available, flux densities extracted from the Galactic and Extragalactic All-Sky Murchison Widefield Array Survey and measurements from the literature to generate improved integrated continuum spectra sampled from ~15 MHz to ~217 GHz. We present the VLSSr images. When possible we combine them with publicly available images at 1.4 GHz, to analyse the resolved morphology and spectral index distribution across each SNR. We interpret the results and look for evidence of thermal absorption caused by ionised gas either proximate to the SNR itself, or along its line of sight. Three of the SNRs, G4.5+6.8 (Kepler), G28.6−0.1, and G120.1+1.4 (Tycho), have integrated spectra which can be adequately fit with simple power laws. The resolved spectral index map forTychoconfirms internal absorption which was previously detected by the Low Frequency Array, but it is insufficient to affect the fit to the integrated spectrum. Two of the SNRs are pulsar wind nebulae, G21.5−0.9 and G130.7+3.1 (3C 58). For those we identify high-frequency spectral breaks at 38 and 12 GHz, respectively. For the integrated spectra of the remaining nine SNRs, a low frequency spectral turnover is necessary to adequately fit the data. In all cases we are able to explain the turnover by extrinsic thermal absorption. For G18.8+0.3 (Kes 67), G21.8−0.6 (Kes 69), G29.7−0.3 (Kes 75), and G41.1−0.3 (3C 397), we attribute the absorption to ionised gas along the line of sight, possibly from extended H IIregion envelopes. For G23.3−0.3 (W41) the absorption can be attributed to H IIregions located in its immediate proximity. Thermal absorption from interactions at the ionised interface between SNR forward shocks and the surrounding medium were previously identified as responsible for the low frequency turnover in SNR G31.9+0.0 (3C 391); our integrated spectrum is consistent with the previous results. We present evidence for the same phenomenon in three additional SNRs G27.4+0.0 (Kes 73), G39.2–0.3 (3C 396), and G43.3–0.2 (W49B), and derive constraints on the physical properties of the interaction. This result indicates that interactions between SNRs and their environs should be readily detectable through thermal absorption by future low frequency observations of SNRs with improved sensitivity and resolution.
Superior functional outcome with dual mobility THR as compared to conventional THR in fracture neck femur: a prospective cohort study
Authors: Agarwala Sanjay , Katariya Ameya , Vijayvargiya Mayank , Shetty Vivek , Swami Pravin Manohar
Published: August 2021

Introduction: Total Hip Replacement (THR) in displaced Fracture Neck of Femur (FNOF) is associated with higher dislocation rates. Conventional THR with a large femoral head and anterior approach has reduced the instability, but it remains higher than THR done for other aetiology. Recent studies have shown reduced dislocation rates with dual mobility THR (DMTHR) for FNOF; however, there is a lack of comparative research to show its superiority over conventional THR. Further, its role in the Asian subcontinent, where the patient requires sitting cross-legged or squatting, has not been studied. Methods: A prospective cohort study of 103 elderly patients with displaced FNOF with a minimum follow-up of 1-year. Fifty-two patients were operated on with DMTHR and fifty-one patients with conventional THR. Both the groups were matched in terms of demographic data, surgical approach, and postoperative protocol. Radiological and functional outcomes in terms of Harris Hip Score (HHS), Range of motion, Patient Reported Outcome Measures (PROM), and Dislocation rate were compared between the two groups. Results: Mean HHS of the DMTHR group was 76.37 at three months and 87.02 at the end of the 1-year postoperatively, which was significantly better than the conventional THR group 65.65 at three months and 72.96 at 1-year. The range of motion was significantly better in the DMTHR group than the conventional THR group. There was no significant difference in radiological outcomes and postoperative dislocation rate between the two groups. Conclusion: Dual mobility implants give better results than conventional implants for primary THA in elderly patients of displaced FNOF regarding better function and greater range of motion.
Its Not about the Destination, Its about the Journey—Plotting 50 Years of Changing Clinical Trends in Plastic Surgery in a Public Sector Teaching Hospital
Authors: Rajan Sheeja , Menedal Akshata , Pereira Carlsen , Chandran Aswathy , Bhaskaran Deepak , Mohammad Najeeb , Thomas Bestin , Sulochana Aabha Das
Published: August 2021

Background The year 2019 marked the 50th anniversary of plastic surgery department of our institution. We present an audit to plot the changing clinical trends in our work in the past five decades.

Methods A single-center retrospective cohort study based on the department demographics was performed and compared across the decades from 1969 to 2019.

Results In 1969, the relative proportion of reconstructive versus cosmetic surgery procedures was 94.32% versus 5.68%; in 2019 this was 76.25% and 23.75%, respectively. An increase of 22 times increase in outpatient registrations, 13.1 times in total surgeries, 642 times in trauma reconstruction, 290 times for hand surgeries, and 323 times for skin tumor surgeries was noted. Male patients (64.9%) increased every decade more than females (35.1%), mostly for trauma surgery and gynecomastia correction. Proportion of pediatric cleft patients have markedly decreased. Spectrum of surgical procedures have widened. Top five reconstructive surgeries in 2019 were limb trauma reconstruction, skin tumor surgeries, hand surgeries, arterio-venous fistula (AV) creation, and oculoplasty. The most common surgery performed was cleft lip surgery in 1969 and hand surgery in 2019. The top five cosmetic surgeries performed in 2019 were scar revisions, nevus excision, liposuction and gynecomastia correction, rhinoplasty, and otoplasty.

Conclusions Data collection and archiving and periodic audits help us study changing trends in our field compared with the global trends. Knowing societal demands will help to improve the resident training in teaching hospitals.
Use of the Vertical Profunda Artery Perforator Flap to Capture the Dominant Perforator: A Cadaver Dissection and Imaging Study
Authors: Artz Jourdain D. , Atamian Elisa K. , Mulloy Clairissa , Stalder Mark W. , Zampell Jamie , Hilaire Hugo St.
Published: August 2021

Background While the originally described transverse profunda artery perforator (tPAP) flap is designed to capture the first profunda perforator, our group hypothesized the dominant perforator may not always be captured in this configuration. This study maps the location of dominant profunda perforators using imaging and cadaveric dissections to determine the probability of capturing dominant perforators with the transverse flap design versus the vertical PAP (vPAP) variant.

Methods Fifty preoperative magnetic resonance angiogram or computed tomographic angiogram scans (100 total extremities) were examined from autologous breast reconstruction patients between 2015 and 2019. Profunda perforator characteristics that were examined included the distance from the pubic tubercle to the infragluteal fold (IGF), the distance of the perforators from the IGF, distance posterior to the gracilis, the diameter of the perforator at fascial exit, and total number of perforators present. Profunda perforator dissection was performed in 18 cadaveric extremities. Analysis included mean distance from pubic tubercle, distance posterior to the gracilis, diameter at fascial exit, and total number of perforators.

Results In imaging analysis, the mean distance from the IGF to the fascial exit of all dominant perforators was 7.04 cm. The mean diameter of the dominant perforator at the fascial exit was 2.61 mm. Twenty-six thighs (26%) demonstrated dominant perforators that exited the fascia greater than 8 cm below the IGF. In cadaver dissections, the mean distance from the pubic tubercle to the fascial exit of all the dominant perforators was 10.17 cm. Nine cadaver specimens (50%) demonstrated perforators that exited the fascia greater than 8 cm below the estimated IGF.

Conclusion The dominant perforator can often be missed in the traditional tPAP design. The vPAP incorporates multiple perforators with a long pedicle, excellent vessel diameter, and favorable donor-site.
Evaluation of CBC Parameters in Relation to PCR Test Results in Diagnosing Pediatric COVID-19 Disease
Authors: Bagci Zafer , Ugur Ayşe Ruveyda , Ugur Cüneyt
Published: August 2021

Objective This study aimed to investigate whether complete blood count parameters have predictive properties in diagnosing coronavirus disease 2019 (COVID-19) in regard to positive polymerase chain reaction (PCR) test in children with a prediagnosis of COVID-19, and whether these parameters are related to the severity of clinical findings in children with COVID-19.

Methods This retrospective cross-sectional study included children who were hospitalized with a possible diagnosis of COVID-19 and had undergone PCR testing in the COVID-19 children's clinic. Probable case definition was made according to the COVID-19 diagnostic and therapeutic guidelines of the Ministry of Health of the Republic of Turkey.

Results A total of 133 patients were included in the study, of which 46 (34.6%) were negative for the PCR test and 87 (65.4%) were positive for the PCR test. white blood cell (WBC), neutrophil, lymphocyte, and platelet levels were significantly lower in the PCR positive group than in the PCR negative group. The platelet to mean platelet volume ratio (PLT/MPV) was significantly lower in the PCR positive group than the PCR negative group, whereas the platelet distribution width (PDW) of the PCR positive patient group was significantly higher than the PCR negative group. For the multivariable model with PDW and neutrophil to lymphocyte ratio/age factors included, F1 score was 0.864, area under the receiver operating characteristics was 0.804, and area under the precision-recall curve was 0.873. The decision tree had a 72.9% cross-validation accuracy value.

Conclusion WBC, neutrophils, lymphocytes, platelets, PLT/MPV, and PDW parameters could be used in conjunction with clinical symptoms and findings to predict the PCR test result.
Method of multi-layer near-field electrohydraulic printing and sintering of nano-silver ink prepared by liquid phase reduction
Authors: Zhang Tiancheng , Yu Zhiheng , Huang Fengli , Tang Chengli , Yang Chao
Published: August 2021

The liquid phase reduction method has a wide application prospect because of its simple equipment and low cost. However, the disadvantages, such as uneven particle size distribution and easy agglomeration of particles, make it difficult to prepare high-concentration nanoparticle ink by this method, which limits its application in the manufacture of high-resolution electronic products. This paper presents a printing and sintering process for low-concentration ink prepared by the liquid reduction method. First, the set pattern is printed by the near-field electrohydraulic printing method. At the same time as multi-layer printing, the substrate is heated by the collecting plate to accelerate the evaporation of the solvent in the printed pattern. Then, the printed multi-layer micro-conductive pattern is solidified by a hot/pressure sintering machine. This method can overcome the edge diffusion effect caused by poor ink viscosity effectively and obtain printing patterns with high thickness, high conductivity, and high resolution. The drying time of different ink layers, the pressure and temperature of hot/pressure sintering, and other parameters were studied in this paper. The electrical conductivity and reliability of the pattern with different printing layers are also analyzed, which provides a reference for the printing and sintering of low-concentration ink in the future.
Analytical modeling and DEM analysis of soil–wheel interaction under cornering and skidding conditions in off-road vehicles
Authors: Hu Cheng , Gao Jingwei , Song Xiaobo , Zhang Min , Tan Xuhong
Published: August 2021

Soil–wheel interaction under cornering and slip conditions (SWICS) has a significant impact on the steering performance of off-road vehicles. In order to analyze the six-dimensional wheel forces in SWICS, a SWICS model based on the analytical method and the discrete element method (DEM) is developed in this paper. First, the modeling process of SWICS using the analytical method was detailed to predict the six-dimensional wheel forces in SWICS. The SWICS was then modeled using the DEM, which involved the following steps: (a) establishment of tire geometry, (b) selection of particle parameters, (c) parameter calibration, and (d) particle generation. Finally, DEM simulations were carried out for different slip angles and slip ratios under three loads, and the results were compared with those of the analytical model. The results show that the SWICS DEM model in this paper maintains a good fit with the analytical model, validating the efficiency of the DEM model and the parameter calibration method. The slip angle has a great influence on the lateral force, overturning moment, and aligning moment and a smaller impact on the normal force, drawbar pull, and rolling resistance moment. The slip ratio promotes an increase in the drawbar pull and rolling resistance moment but reduces the value of the lateral force and aligning moment. The research in this paper provides a DEM modeling approach and an analysis method for solving mechanical problems with different dimensions in SWICS, which will help improve the performance of off-road vehicles.
Nonlinear stability characteristics of rotating plane channel Poiseuille flow with the outcome of nonlinear evolution equation
Authors: Khan Muhammad Ijaz
Published: August 2021

This paper considers the laminar to turbulent transition of pressure-gradient driven Poiseuille flow in a plane channel system rotating with some angular speed under the influence of the Coriolis force. The nonlinearities are taken into account in the fundamental equations of motion for the perturbations grown enough to cause laminar to turbulent transition in rotating channel flow. For the values of Reynolds number slightly greater than the critical values above which the perturbations may grow, the time and length scales are chosen for the slow variations in the amplitude parameter B of a nonlinear two-dimensional perturbation wave in plane channel flow rotating as a whole. By the method of multiple scales, the nonlinear complex evolution equation, called here the Ginzburg–Landau–Stewartson–Stuart equation, is derived for scalar function B dependent on slow and long scale variables of both time and space. The coefficients of this equation are calculated analytically and computationally, which contain all the parameters causing laminar to turbulent transition along with the departure parameter from the neutral stable surface toward the growing side. The laminar to turbulent transition can be analyzed by the solution of this nonlinear equation, which is dependent on its coefficients containing the non-dimensional flow parameters.
Comparative study of modal decomposition and dynamic equation reconstruction in data-driven modeling
Authors: Yin Zhenglong , Fan Bo , Ding Zijing , Wu Zongyu , Chen Yong
Published: August 2021

Due to the increasing complexity of dynamic systems, it is increasingly difficult for traditional mathematical methods to meet the modeling requirements of complex dynamic systems. With the continuous innovation of computer and big data technologies, massive data can be easily obtained and stored. Therefore, studies of dynamic system modeling through data-driven approaches have attracted more and more researchers’ attention. This paper compares the dynamic mode decomposition method and dynamic equation reconstruction. Taking Lorenz and nonlinear Helmholtz resonant systems as examples, the two methods show the ability to reconstruct and describe the evolution characteristics of the dynamic system. Specifically, the dynamic mode decomposition method can describe the characteristics of the dynamic system more intuitively; however, it cannot provide physical insights. On the other hand, the discovery of dynamic equations from data can more accurately express the physical evolution characteristics of the dynamic system; however, it is easily affected by random noise. Because the dynamic mode decomposition method can obtain a reduced-order model, which can not only retain useful information of the original data but also reduce the noise disturbances, it can effectively improve the noise attenuation and finally reconstructions of differential dynamical equations.
Study on vibration transfer characteristics of liquid filled double-walled cylindrical shells with elastic connection
Authors: Yu Anbin , Zhao Yinglong , Chen Meixia
Published: August 2021

In order to study the vibration isolation characteristics in water, based on the Flügge theory, a double-walled cylindrical shell model with spring connection is established using the wave propagation method. The fluid inside the inner shell is considered in the model. The reliability of the theoretical method is verified by comparing the calculation results of the mean square velocity with those of the finite element method. The effects of spring stiffness, spring number, fluid load, and inter-shell fluid thickness on vibration transmission of inner and outer shells are studied. The results show that the fluid loading effect of the water medium inside the inner shell can act on the inner shell and the outer shell simultaneously, while the fluid loading effect of the outboard fluid only acts on the outer shell. Under the condition of keeping the total spring stiffness unchanged, increasing the number of springs can reduce the vibration transmission from the inner shell to the outer shell, especially the vibration transmission from the inner shell to the outer shell at low frequencies. The “vibration short circuit” effect easily occurs in the inter-shell water, which is independent of the thickness of inter-shell water. When the elastic connection stiffness is small, the inter-shell water plays a leading role in vibration transmission in the whole frequency range. When the stiffness of elastic connection is large, the inter-shell water plays a leading role in vibration transmission at low frequencies, while the elastic connection plays a leading role in vibration transmission at high frequencies.
Determining the effects of sperm activation in anuran cloaca on motility and DNA integrity in
Authors: Arregui Lucía , Martinez-Pastor Felipe , Arroyo Francisca , Gosálvez Jaime
Published: August 2021

The effect of time inside the animal’s cloaca on sperm quality after hormone-induced spermiation is unknown. However, this knowledge is critical for the development of assisted reproductive biotechnologies in amphibians. Out-of-season spermatozoa were collected from Epidalea calamita for 4 h after injection of 10 IU g−1 human chorionic gonadotrophin either hourly (Group I (n = 10); four samples per male) or every 2 h (Group II (n = 9); two samples per male). Sperm samples were assessed for motility and DNA integrity using the sperm chromatin dispersion (SCD) test and the sperm chromatin structure assay (SCSA). The collection strategy affected total motility (mean (±s.e.m.) 84.4 ± 9.9% vs 73.6 ± 16.7% in Group I and II respectively; P = 0.014) and the sperm motility index (67.6 ± 17.7% vs 57.6 ± 16.3% in Group I and II respectively; P = 0.034). There was a significant effect of the male in Group II, but not in Group I. In Group I, the quality of the first samples collected was lower than that of samples collected thereafter (P ≤ 0.032). No significant correlations were found between the results of the SCD test and SCSA, showing that these techniques provide different information in this species. In conclusion, collecting spermatozoa every hour resulted in better sperm quality and may be more efficient. However, the between-male differences were considerable and collection of spermatozoa at just 1 h after hormone treatment produced lower-quality spermatozoa.
DISCO is key to successful centriole maturation
Authors: Gaudin Noémie , Martin Gil Paula , Azimzadeh Juliette
Published: August 2021

Centriole maturation is essential for ciliogenesis, but which proteins and how they regulate ciliary assembly is unclear. In this issue, Kumar et al. (2021. J. Cell Biol. https://doi.org/10.1083/jcb.202011133) shed light on this process by identifying a ciliopathy complex at the distal mother centriole that restrains centriole length and supports the formation of distal appendages.
High-efficiency unidirectional wavefront manipulation for broadband airborne sound with a planar device
Authors: Tan Yang , Liang Bin , Cheng Jianchun
Published: August 2021

In the past decade, one-way manipulation of sound has attracted rapidly growing attention with application potentials in a plethora of scenarios ranging from ultrasound imaging to noise control. Here we propose a design of a planar device capable of unidirectionally harnessing the transmitted wavefront for broadband airborne sound. Our mechanism is to use the broken spatial symmetry to give rise to different critical angles for plane waves incident along opposite directions. Along the positive direction, the incoming sound is allowed to pass with high efficiency and be arbitrarily molded into the desired shape while any reversed wave undergoes a total reflection. We analytically derive the working bandwidth and incident angle range, and present a practical implementation of our strategy. The performance of our proposed device is demonstrated both theoretically and numerically via distinct examples of production of broadband anomalous refraction, acoustic focusing and non-diffractive beams for forward transmitted wave while virtually blocking the reversed waves. Bearing advantages of simple design, planar profile, broad bandwidth and high efficiency, our design opens the possibility for novel one-way acoustic device and may have important impact on diverse applications in need of special control of airborne sound.
High amplification laser-pressure optic enables ultra-low uncertainty measurements of optical laser power at kilowatt levels
Authors: Artusio-Glimpse Alexandra B , Rogers Kyle A , Williams Paul A , Lehman John H
Published: August 2021

We present the first measurements of kilowatt laser power with an uncertainty less than 1%. These represent progress toward the most accurate measurements of laser power above 1 kW at 1070 nm wavelength and establish a more precise link between force metrology and laser power metrology. Radiation pressure, or photon momentum, is a relatively new method of non-destructively measuring laser power. We demonstrate how a multiple reflection optical system amplifies the pressure of a kilowatt class laser incoherently to improve the signal to noise ratio in a radiation pressure-based measurement. With 14 incoherent reflections of the laser, we measure a total uncertainty of 0.26% for an input power of 10 kW and 0.46% for an input power of 1 kW at the 95% confidence level. These measurements of absolute power are traceable to the SI kilogram and mark a state-of-the-art improvement in measurement precision by a factor of four.
An efficient hybrid conjugate gradient method with descent properties under strong Wolfe line search
Authors: Sulaiman I M , Mamat M , Hassan Basim A. , Ghazali P L , Ahmad M Z
Published: August 2021

The hybrid conjugate gradient parameters are among the efficient variants of conjugate gradient (CG) methods for solving large-scale unconstrained optimization problems. This is due to their nice convergence properties and low memory requirements. In this paper, we present a new hybrid conjugate gradient method based on famous CG algorithms for large-scale unconstrained optimization. The proposed hybrid CG method can generate a descent search direction at each iteration provided the strong Wolfe line search is employed. Numerical results have been presented which show that the proposed method is efficient and promising.
Modified higher order block backward differentiation formula for third order ordinary differential equations
Authors: Asnor A I , Yatim S A M , Ibrahim Z B
Published: August 2021

This study is aimed to modify higher order block backward differentiation formulae for dealing with the third order stiff ordinary differential equations (ODEs). Two new solutions are acquired at each step by using a few back values in preceding blocks. Apart from that, the differentiation coefficients will be stored, thus, repetitive calculations of the coefficients can be avoided as well as computational cost can also be optimized. A comparative analysis will be presented once the numerical experiments have been conducted to a few considered problems in order to confirm the efficiency of the proposed method with the existing stiff ODE solver. The analysis proves the accuracy and efficiency of the proposed method can be served as another alternative for third order stiff ODEs.
Modeling Fuzzy B-spline Interpolation Series using α-cut operation for spatial earth surface problem
Authors: Abu Bakar N A , Yusoff B , Wahab A F , Mamat M
Published: August 2021

In this paper, the series of α-cut is also known as the α-cut operation used to construct a new model of surface called Fuzzy B-spline Interpolation Series surface. The surface is called Fuzzy B-spline Interpolation Series because of the various values of α chosen in the fuzzification method. Then, the operation is combined into a B-spline surface model. This new proposed model will be used to solve spatial earth surface problems in every collected data points. The spatial earth data have values in latitude, longitude and altitude. All these values are considered as uncertainty data because of the satellite’s measurement errors. Finally, constructed surfaces’ results will be compared between raw data’s surface and Fuzzy B-spline Interpolation Series surface.
First order polarization tensor approximation using multivariate polynomial interpolation method via least square minimization technique
Authors: Sukri Suzarina Ahmed , Hoe Yeak Su , Khairuddin Taufiq Khairi Ahmad
Published: August 2021

This paper proposes a new numerical approach useful in dealing with nearly singular integrals, specifically, the integral of the first order polarization tensor (PT). Polarization tensor represents the integral equations in an asymptotic series, and it can also define the boundary value problem of a partial differential equation (PDE). Since PT has been widely used and implemented in many engineering areas, particularly electric and magnetic field areas, it is crucial to estimate the first order PT solutions accurately. In this regard, the computation of PT for different geometry types is basically from the quadratic interpolation and the multivariate polynomial fitting using the least square method. The numerical calculation of the integral of the singular integral operator, ??∗which is one of the primary integral processes before we obtained the solution of PT uses the multivariate polynomial fitting. This paper aims to provide an accurate numerical solution for first order PT for different geometry types, particularly sphere and ellipsoid geometry. The numerical results of the proposed method are shown together with the comparison of its analytical solutions. From the results obtained, the numerical solution of first order PT shows higher accuracy and higher convergence as the number of surface elements increases. The numerical and the analytical solution of first order PT for a sphere is discussed and represented in graphical form. The utilization of two different software types throughout this study is Netgen Mesh Generator and MATLAB to aid the numerical computation process. The simulation and the numerical examples verify the effectiveness and efficiency of the proposed method.
Determination of trigonometric Fourier’s series by the method of four-dimensional mathematics
Authors: Rakhymova A T , Ahmedov A A , Shapen K M
Published: August 2021

This paper is devoted to the determination of the trigonometric Fourier series by the method of four-dimensional mathematics. In this paper, a new four-dimensional method for evaluation of the sums containing trigonometric function is proposed. Current work provides a first study and finding towards Fourier’s series in four-dimensional space.
Curvelet Based Texture Features for Breast Cancer Classifications
Authors: Yasiran Siti Salmah , Salleh Shaharuddin , Sarmin Norhaniza , Mahmud Rozi , Halim Suhaila Abd
Published: August 2021

One of the sources of death among women is breast cancer. It is well known that Mammogram is the best method for breast cancer detection. Subsequently, there are solid requirements for the improvement of computer aided diagnosis (CAD) systems to assist radiologists in making decision. In this paper, the curvelet changes is proposed to classify the breast cancer. Curvelet refers to multi-level change which have the characteristics of directionality and anisotropy. It splits several characteristic impediments of wavelet to edges of an image. Two component extraction techniques were created associated with curvelet and wavelet coefficients to separate among various classes of breast. Finally, the K-Nearest Neighbor (KNN) classifiers were utilized to decide if the district is unusual or ordinary. The adequacy of the suggested strategies has been implemented with Mammographic Image Analysis Society (MIAS) data images. All the dataset is utilized by the suggested strategies. Then calculations have been applied with both curvelet and wavelet for correlation test were performed. The general outcomes show that curvelet change shows superior compared to the wavelet and the thing that matters is measurably noteworthy.
The ability and analysis of Students’ errors in the topic of algebraic expression
Authors: Adnan Mazlini , Abidin Zulhilmi Zainal , Mustam Afian Akhbar , Maat Siti Mistima , Sutama Sutama , Prihaswati Martyana , Zulnaidi Hutkemri
Published: August 2021

This study aimed to determine the level of ability of Form One students in the topic of algebraic expressions based on the six levels in the Bloom’s Taxonomy Revision. In addition, this study aimed to identify the types of errors of form one students in the topic of algebraic expressions based on Newman’s Error Analysis. Respondents of this study consist of 68 form one students were selected from school in Melaka through simple random sampling method. The data in this study has been analysed in a descriptive basis involving frequency, percentages and mean. This study uses the application of [[CHECK_SINGLEQUOT_ENT]] Statistical Package of Social Science (SPSS) version 26 for the purpose of this analysis. The findings showed that the students have troubled in the topic of algebra. 3 of 6 levels in the Bloom’s Taxanomy cannot be responded well by these students. Students only show high levels of mastery in the first two levels of remembering and understanding levels. Students have the most significant problems at evaluating level with the lowest percentage. The findings of this study also showed that most of students make an error in transformation. This study showed that error reading is lowest. In conclusion, these students have a problem answering the question of algebra and the type of common mistakes that are transformational problems. The implications of this study are, the Ministry and the teachers are able to makes reference to the difficult levels and the types of errors often made by form one students in the topic of algebra.
A robust algorithm for global optimization problems
Authors: Kerk Lee Chang , Lau Gee Choon , Ahmad Shamsatun Nahar , Shamala Palaniappan , Mokhtar Nurkhairany Amyra , Ang Tau Keong
Published: August 2021

In this paper, a global optimization algorithm namely Kerk and Rohanin’s Trusted Region is used to find the global minimizers by employing an interval technique; with it, the algorithm can find the region where a minimizer is located and will not get trapped in a local one. It is able to find the convex part within the non-convex feasible region. This algorithm has descent property and global convergence. The numerical results have shown the algorithm has an outstanding capability in locating global minimizers.