bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical investigation of the effect of advance ignition timing on combustion process in direct injection rotary engine fueled with biodiesel
Authors: Otchere Peter , Pan Jianfeng , Fan Baowei , Chen Wei , Yao Lu , Jianxing Li 
Published: October 2019

AbstractBiodiesel is a clean energy source that helps in the reduction of environmental pollution as compared to fossil fuel. This study aimed to improve the performance of combustion and reduce emission in direct injection rotary engine by fueling it with biodiesel as well as selecting the best ignition time. A 3D‐dynamic simulation model was established and then coupled with biodiesel chemical kinetics mechanism. On this basis, investigation of five ignition timings (IT) was conducted to know their various effects on combustion process. The simulation results showed that properly advancing IT increased in‐cylinder pressure, with the peak pressure (Pmax) of 35°CA (BTDC) IT of 45.99 bar the largest. Comparing IT of 35°CA (BTDC) with the IT of the original engine showed an 18.14% increase in peak pressure. The corresponding crank angle (φmax) for Pmax values also proved that when the IT was advanced, φmax values decreased and that of 35°CA (BTDC)‐10.37°CA (ATDC), 30°CA (BTDC)‐11.46°CA (ATDC), and 25°CA (BTDC)‐13.88°CA (ATDC) were better because they were generally between 10–15°CA (ATDC), which contributes to better engine performance. With advanced IT, phase of total period during combustion was continuously brought forward due to flame propagation acceleration by tumble as well as increase of tumble residence effect time that aided in improving the combustion rate. The burnt fuel mass fractions at TDC of 40°CA (BTDC) IT of 0.94 was the highest followed by 35°CA (BTDC) IT of 0.88. Under this computational condition, 35°CA (BTDC) was deemed to be the improved combustion scheme though soot exhaust increased.
A state of the art review of PV‐Trombe wall system: Design and applications
Authors: Ahmed Omer K. , Hamada Khalaf I. , Salih Abdulrazzaq M. , Daoud Raid W. 
Published: October 2019

AbstractGlobal energy demand for the future can be met using renewable energy resources, and one of its harvesting tools is the photovoltaic (PV) technology. The combination of solar cell technology and Trombe wall is one of the most important research topics at present. PV‐Trombe walls are receiving great attention because of their applications for simultaneous electricity generation and heating. In this article, a review of available literature covers different designs of a PV‐Trombe wall system besides its thermal and electrical applications. The review covers in detail the influence of design and operational parameters including the glass cover, use of direct current fan, facade width, air vent, air gap thickness, thermal insulation, packing factor, coverage, heat storage, air mass flow rate, PV cell cooling, southern windows, and tilt angle of solar cell on the performance of PV‐Trombe walls. Furthermore, comparison between the PV‐Trombe wall system and classical Trombe wall as well as the applicability of this novel system are revealed. This review article is beneficial to engineers and researchers and can provide information for future studies.
Preparation of NiFe2O4/polythiophene nanocomposite and its enhanced adsorptive uptake of Janus green B and Fuchsin basic from aqueous solution: Isotherm and kinetics studies
Authors: Hussain Daud , Siddiqui M. Fuzail , Khan Tabrez A. 
Published: October 2019

AbstractNiFe2O4/polythiophene nanocomposite was synthesized by in situ chemical oxidative polymerization of thiophene in NiFe2O4 nanoparticles presence, whereas NiFe2O4 nanoparticles were prepared via coprecipitation method. Fourier transform infrared (FTIR), X‐ray diffraction (XRD), UV–Visible, and SEM, EDX techniques were used for characterization of the nanocomposite. The effect of various parameters such as adsorbent dose, contact time, initial dye concentration, and initial pH of solution on the adsorption of Janus green B (JG) and Fuchsin basic (FB) onto the nanocomposite was optimized by batch studies. The equilibrium uptake data ascribed well to the Langmuir model with maximum adsorption capacity of 143 and 498 mg/g at 303 K for JG and FB, respectively. The exceptional high adsorption capacity of NiFe2O4/polythiophene nanocomposite for JG and FB was ascribed to π‐π and electrostatic interactions. Kinetics studies pointed out that JG and FB removal followed pseudo‐second order model. The negative values of ΔH° (JG: –47.28; FB: −38.00 kJ/mol) and ΔG° (JG: −9.347 to −6.442; FB: −14.16 to – 12.85 kJ/mol) pointed out the feasibility, spontaneity, and exothermic nature of removal process. Negative value of ΔS° (JG: –0.125; FB: –0.078 kJ/mol) suggested decrease in randomness at the solid/liquid interface. The results showed that NiFe2O4/polythiophene is an appealing adsorbent for the uptake of JG and FB dyes from aquatic environment.
Optimization and maximum efficiency of concentrating photovoltaic cell‐gas turbine system with spectrum splitting
Authors: Dang Liqin , Yang Zhimin , Lin Guoxing , Chen Jincan 
Published: October 2019

AbstractThe spectrum splitting system (SSS) is an efficient approach to relieve the energy losses in the solar cell and boost the efficiency of solar energy utilization. A model of the concentrated solar spectrum splitting photovoltaic (PV) cell‐gas turbine (GT) hybrid system is established to evaluate the performance of the system and predict the maximum efficiency. The numerical calculations show that the area ratio of the solar collector to the PV cell significantly affects the maximum efficiency of the spectrum system, but most of the previous studies are not considered. The maximum efficiency of the system is 50.6% when the parameters including the cell voltage, collector temperature, and band gap energy of the PV cell are optimized at the same areas of the collector and PV cell. The proposed SSS can achieve the maximum efficiency of 52.3% when the area ratio of the collector to the PV cell is further optimized. The results obtained are compared with those of a single concentrating PV cell or solar‐powered GT, and consequently, the advantages of a concentrating spectrum splitting PV cell‐GT hybrid system are revealed.
Techno‐economic feasibility analysis of integrating grid‐tied solar PV plant in a wind farm at Harapanahalli, India
Authors: Yendaluru Raja Sekhar , Karthikeyan Gautham , Jaishankar Aishwarya , Babu Sarath 
Published: October 2019

AbstractEnergy in different forms is required to drive a nation's growth and its sustenance. However, a significant issue that plagues the world is exploitation of fossil fuel negligently, for domestic and commercial requirements. The Government of India (GoI) has devised its renewable energy policies to encourage and promote the use of renewable energy sources in an efficient manner. In this paper, feasibility is explored for employing solar PV power generation at a wind power generation site through hybridization such that power production can be improved throughout the year. Simulation studies have been conducted for the site using RETScreen to analyze hybrid power generation at Harapanahalli in Karnataka, India. The wind farm has 18 wind turbine generator (WTG's) installed, having 2 MWe capacities each, producing 36 MWe supplied to the local grid. By using sun path and shadow analysis for the site, it is calculated that 344,531.25 m2 of shadow‐free space is available which can be suitably used for alternate methods of power generation. From the present analysis, it is predicted that annual power generation capacity of the site can be improved by about 90% on adopting hybrid power generation. The project cost is pegged at 188 crores Indian rupees (INR) and the payback period of the hybrid system was ascertained to be approximately 7 years.
The diagnosis values of serum STAT4 and sEng in preeclampsia
Authors: Zhang Luyan , Li Xuechun , Zhou Chengcheng , You Zhengming , Zhang Jianwei , Cao Guomei 
Published: October 2019

AbstractObjectiveTo detect the levels of signal transducer and activator of transcription 4 (STAT4) and soluble endoglin (sEng) in preeclampsia patients and analyze the diagnostic values of STAT4 and sEng in preeclampsia.MethodsFifty‐four pregnant women with preeclampsia from October 2017 to June 2018 were included in this study. Twenty‐eight matched healthy pregnant women were set as the control group. The general clinical characteristics were measured. Serum STAT4 and sEng were detected by ELISA. Correlation between STAT4 and sEng, and their diagnostic value in preeclampsia were analyzed.ResultsCompared with control, the prothrombin time in preeclampsia was significantly lower, while the mean arterial pressure, 24‐hour urine protein, serum creatinine, fibrinogen, and ALT were significantly higher. The circulating levels of STAT4 and sEng were significantly increased in the preeclampsia. The serum levels of STAT4 and sEng in preeclampsia were positively correlated. For the diagnosis of preeclampsia by the serum STAT4, AUC is 0.902, and the sensitivity and specificity are 0.893 and 0.929. By the serum sEng, AUC is 0.873, and the sensitivity and specificity are 0.816 and 0.905.ConclusionThe serum levels of STAT4 and sEng were significantly increased in preeclampsia with disease severity status, which have promise as diagnostic markers in preeclampsia.
Aquaporin‐2 and Na+/H+ exchanger isoform 1 modulate the efficiency of renal cell migration
Authors: Di Giusto Gisela , Pizzoni Alejandro , Rivarola Valeria , Beltramone Natalia , White Alan , Ford Paula , Capurro Claudia 
Published: October 2019

AbstractAquaporin‐2 (AQP2) promotes renal cell migration by the modulation of integrin β1 trafficking and the turnover of focal adhesions. The aim of this study was to investigate whether AQP2 also works in cooperation with Na+/H+ exchanger isoform 1 (NHE1), another well‐known protein involved in the regulation of cell migration. Our results showed that the lamellipodia of AQP2‐expressing cells exhibit significantly smaller volumes and areas of focal adhesions and more alkaline intracellular pH due to increased NHE1 activity than AQP2‐null cells. The blockage of AQP2, or its physically‐associated calcium channel TRPV4, significantly reduced lamellipodia NHE1 activity. NHE1 blockage significantly reduced the rate of cell migration, the number of lamellipodia, and the assembly of F‐actin only in AQP2‐expressing cells. Our data suggest that AQP2 modulates the activity of NHE1 through its calcium channel partner TRPV4, thereby determining pH‐dependent actin polymerization, providing mechanical stability to delineate lamellipodia structure and defining the efficiency of cell migration.
Long noncoding MIAT acting as a ceRNA to sponge microRNA‐204‐5p to participate in cerebral microvascular endothelial cell injury after cerebral ischemia through regulating HMGB1
Authors: Deng Wenjing , Fan Chenghe , Shen Ruile , Wu Yanzhi , Du Ran , Teng Junfang 
Published: October 2019

AbstractThis study is applied to the investigation of the long noncoding RNA myocardial infarction associated transcript's (MIAT's) role in regulating the expression of high‐mobility group box 1 (HMGB1) in cerebral microvascular endothelial cell (CMEC) injury after cerebral ischemia by serving as a competitive endogenous RNA (ceRNA) to sponge microRNA‐204‐5p (miR‐204‐5p). The cerebral ischemia model of middle cerebral artery occlusion (MCAO) in rats was established by the suture method, in which rats were injected with empty plasmids and MIAT siRNA plasmids. The cerebral ischemia injury model in vitro was established through oxygen glucose deprivation (OGD) in primary cultured CMECs in rats. The cells were transfected with empty plasmids and MIAT siRNA plasmids. The MIAT/miR‐204‐5p/HMGB1 axis’ function in damage and angiogenesis of CMECs were explored. The binding site between MIAT and miR‐204‐5p along with that between miR‐204‐5p and HMGB1 was determined. MIAT was overexpressed in MCAO rats’ brain tissue and inhibited MIAT attenuated the injury of brain tissue in MCAO rats. Inhibition of MIAT promoted angiogenesis, promoted miR‐204‐5p expression and inhibited HMGB1 expression in brain tissue of MCAO rats. Inhibition of MIAT reduced CMEC damage, induced angiogenesis of CMECs, increased the number of surviving neurons, promoted miR‐204‐5p expression and inhibited HMGB1 expression in CMECs treated with OGD. MIAT promoted HMGB1 expression by competitive binding to miR‐204‐5p to regulate the injury of CMECs after cerebral ischemia. Our study showed that MIAT promoted HMGB1 expression by competitively binding to miR‐204‐5p to regulate the injury of CMECs after cerebral ischemia.
Single‐session multiple stent deployment using moving cell stent without dilating initial stent mesh to treat malignant hilar biliary obstruction (with videos)
Authors: Ogura Takeshi , Takenaka Mamoru , Shiomi Hideyuki , Nishioka Nobu , Ueno Saori , Miyano Akira , Kamiyama Rieko , Higuchi Kazuhide 
Published: October 2019

AbstractBackgroundMalignant hilar biliary obstruction (MHBO) can be treated with bilateral self‐expandable metal stents (SEMS) deployed using side‐by‐side (SBS) or stent‐in‐stent (SIS) techniques. Moving cell stents (MCS) are a novel type of SEMS. The present study evaluated the technical feasibility of treating MHBO using bilateral novel uncovered SEMS to insert an SIS technique without dilating the mesh of a first stent within a single session.MethodWe retrospectively assessed patients who were complicated with obstructive jaundice due to MHBO between August and December 2018. Technical success was defined as the deployment of a bilateral MCS into two or more biliary tracts using SIS technique without a dilation device.ResultsThe present study analyzed data from 23 consecutive patients who were complicated with MHBO. Bilateral SIS technique with MCS was deployed in 22 (95.6%) of the 23 patients without dilating the mesh of the first stent. Multiple guidewire insertion failed in one patient with Bismuth‐type IV. The median procedural duration was 33.6 min. Time to recurrent biliary obstruction was 230 days. Severe adverse events were not seen in any patients.ConclusionIn conclusion, uncovered moving cell SEMS might facilitate bilateral stent deployment using SIS technique.
Extensive full thickness abdominal wall reconstruction using anterolateral thigh compound flap modifications
Authors: Oh Jeongseok , Oh Joon Seok , Eun Seok‐Chan 
Published: October 2019

AbstractPurposeAbdominal wall reconstruction is challenging, which demands adequate skin coverage and structural support. The anterolateral thigh (ALT) flap including fascial portion can be useful in such cases.MethodsRetrospective chart review of five patients that underwent complex abdominal wall defects reconstruction with ALT free flaps with fascia lata was conducted. Patient age ranged from 49 to 69 years (average: 57.4). The etiology of defects was infected liposuction site, small bowel perforation, esophageal cancer, diverticulum perforation, and Hartmann operation. The average size of the defect was 17.4 × 10 cm (9 × 9 ~ 21 × 18). Single‐stage reconstruction using ALT flaps based on the lateral circumflex femoral artery was done in all patients. Exposed intestines were successfully covered and reinforced utilizing fascial component.ResultsThe average size of the flap was 17.4 × 8 cm (9 × 9 cm ~25 × 10 cm). One partial flap necrosis, venous congestion, and infection occurred. These complications were treated successfully. During the follow‐up (12–96 months, mean: 63), all patients achieved functional stabilization and returned to normal activities.ConclusionALT flap combined with its fascial component is useful for abdominal wall. It can be a reliable option in cases of intestinal exposure.
Late‐Night Eating‐Induced Physiological Dysregulation and Circadian Misalignment Are Accompanied by Microbial Dysbiosis
Authors: Ni Yinhua , Wu Lianxin , Jiang Jinlu , Yang Tianqi , Wang Ze , Ma Lingyan , Zheng Liujie , Yang Xin , Wu Zeming , Fu Zhengwei 
Published: October 2019

ScopeIrregular eating habits, such as late‐night eating, will cause increased risk of obesity and other metabolic diseases. The aim of this study is to elucidate the impacts of late‐night eating on physiological function and gut microbiota.Methods and resultsMale Wistar rats under 16 h/8 h‐light/dark cycle are divided into four groups with specific dietary habits, which mimicked breakfast, lunch, dinner, and late‐night eating. Late‐night eating, including skipping dinner for a night eating (BLN) and skipping breakfast and having a night eating (LDN), causes an increase of body weight, which is associated with decreased physical activity. Additionally, late‐night eating results in hepatic lipid accumulation and systemic inflammation in peripheral tissues, compared to those of free feeding (FF) or breakfast, lunch, and dinner (BLD) groups. The phases of key clock genes are similar in FF, BLD, and BLN groups, while LDN feeding causes an overall 4 h phase delay in peripheral tissues. Moreover, late‐night eating, especially LDN feeding, results in a significant alternation in the compositions and functions of gut microbiota, which further contributes to the development of metabolic disorder.ConclusionLate‐night eating causes physiological dysregulation and misalignment of circadian rhythm, together with microbial dysbiosis.
Compact multiband CPW fed monopole antenna with square ring and T‐shaped strips
Authors: Karthikeyan Madurakavi , Sitharthan Ramachandran , Ali Tanweer , Roy Bappadittya 
Published: October 2019

AbstractA novel compact wideband antenna with T‐shaped strips inside square ring is proposed. By stacking a pair of T‐shaped strip one above another, the antenna covers the WIMAX (3.3‐3.8 and 5.25‐5.85 GHz), WLAN (2.41‐2.54, 5.15‐5.35, and 5.72‐5.85 GHz), and lower band of future 5G communications (3.6‐6 GHz). The antenna is fabricated on 17 × 33 × 1.6 mm3 FR‐4 substrate. UWB operation is achieved using a rectangular shaped slot in the ground plane. The designed antenna has been fabricated and measured. Simulation results and measured results are in good agreement.
A compact octagonal‐ring monopole antenna for super wideband applications
Authors: Okan Tayfun 
Published: October 2019

AbstractA compact monopole super wideband antenna has been designed and fabricated in this study. The proposed antenna consists of an octagonal‐ring shaped patch with a stub positioned on the top right corner of it to enhance the impedance bandwidth. Further improvement is ensured by optimally shifting both the patch and feed line away from the center line, and introducing a notch on the ground plane. The fabricated antenna covers the frequency band from 2.59 to 31.14 GHz with a reflection coefficient of |S11| ≤  − 10 dB. It has a bandwidth of 28.55 GHz, fractal bandwidth percentage of 169% and bandwidth ratio of 12.02:1. Omnidirectional radiation characteristics are observed over the operating bandwidth in the far‐field measurements. Furthermore, the far‐field radar cross section measurement of the antenna is also simulated on PC and relatively low values are obtained through the operating bandwidth. Presented antenna has a relatively small size (40 × 40 × 1.01 mm3) and exhibits good gain and efficiency characteristics in comparison to studies with similar bandwidth.
Self‐calibrating wave‐encoded 3D turbo spin echo imaging using subspace model based autofocusing
Authors: Zhou Zechen , Yuan Chun , Börnert Peter 
Published: October 2019

PurposeTo develop a self‐calibrating approach for the estimation of wave point spread function (PSF) and coil sensitivities from the subsampled wave‐encoded k‐space, and evaluate its performance for wave‐encoded 3D turbo spin echo (TSE) imaging.MethodsA low rank subspace parametric model was demonstrated in simulation to improve the representation for practical wave encoding k‐space trajectories with aperiodicity, and an autofocus metric for the entire imaging volume was used to calibrate the wave PSF in a 2‐stage manner from coarse to refined estimation. The coil sensitivities can be extracted from the shifted central region of wave PSF corrected subsampled k‐space, and further used with wave PSF for wave‐encoded parallel imaging (PI) reconstruction. The wave encoding gradients were integrated into the 3D TSE sequence considering eddy current reduction aspects and maintaining of the Carr‐Purcell‐Meiboom‐Gill condition. Phantom and in vivo brain experiments were performed to evaluate the accuracy of wave PSF self‐calibration and to compare the PI reconstruction performance between wave and Cartesian encoding scheme.ResultsThe self‐calibrated wave PSF, estimated from different k‐space undersampling patterns can robustly correct the wave encoding induced image artifacts given sufficient central autocalibration data. The self‐calibrating wave‐encoded PI reconstruction has demonstrated its improved performance in reduced aliasing artifacts and noise amplification in comparison to the Cartesian‐encoded PI reconstruction results for 3D TSE imaging.ConclusionThe proposed self‐calibrating wave‐encoded method allows robust calibration of wave PSF and coil sensitivities from the subsampled k‐space, and improves the overall image quality for accelerated 3D TSE imaging.
Development of intravoxel inhomogeneity correction for chemical exchange saturation transfer spectral imaging: a high‐resolution field map‐based deconvolution algorithm for magnetic field inhomogeneity correction
Authors: Sun Phillip Zhe 
Published: October 2019

PurposeCEST MRI is sensitive to dilute proteins/peptides and microenvironmental properties yet susceptible to magnetic field inhomogeneity. We aimed to develop a high‐resolution field map‐based CEST intravoxel inhomogeneity correction (CIVIC) algorithm for CEST Z‐spectral imaging.MethodsThe proposed CIVIC approach treats the intravoxel inhomogeneity as a point spread function and applies the deconvolution algorithm to reconstruct the original Z‐spectrum. We simulated the effect of B0 field inhomogeneity on CEST measurement and tested the efficacy of the proposed CIVIC algorithm. We also performed CEST MRI on a dual‐pH Creatine‐gel phantom under varied field homogeneity conditions and compared the CEST MRI contrast‐to‐noise ratio from the raw Z‐spectrum, water saturation shift referencing, and the proposed CIVIC methods.ResultsThe numerical simulation showed that the CIVIC algorithm remains effective even in the case of symmetric field dispersion with a 0 mean shift. The experimental results confirmed that the proposed CIVIC method substantially improves the CEST MRI contrast‐to‐noise ratio under different field homogeneity conditions.ConclusionOur study established a new intravoxel B0 inhomogeneity correction algorithm, promising to facilitate CEST spectral imaging in challenging experimental conditions.