bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alpha (α)-amylase Inhibitory Property of Anthocleista nobilis Leaf Extract
Authors: Dabie Kwabena , Adulley Felix , Ababio Boansi Adu , Yamoah Emmanuel Peprah , Owusuaa Elizabeth 
Published: May 2022

Aims: Alpha (α)-amylase inhibitors from plants are preferable for type 2 diabetes treatment because of their relative potency and safety. This study examined, in vitro, the inhibitory effect of Anthocleista nobilis leaf extract on starch hydrolysis catalyzed by α -amylase (extracted from moated sorghum).
Place and Duration of Study: Department of Biochemistry (School of Biological Sciences) and Department of Chemistry, School of Physical Sciences, University of Cape Coast, Ghana, between June 2021 and August 2021.
Methodology: Leaves of A. nobilis were air-dried, pulverized, and macerated in 70% aqueous ethanol for 72 hrs. The filtrate was concentrated and reconstituted in 0.02M Sodium phosphate buffer (pH 6.9) for further analysis including Phytoconstituents screening. In vitro analysis of α -amylase activity as well as inhibitory effect of A. nobilis extract on α -amylase was performed. The Lineweaver-Burk plot was employed in the inhibition analysis to determine the inhibition type, maximum initial reaction rate (Vmax), as well as the Michaelis constant (KM).
Results: The percentage inhibition of α-amylase ranged from 25.0 ± 0.46% - 85.7 ± 2.17% for 0.1mg/mL and 0.9mg/mL of the A. nobilis leaf extract respectively. The mode of α-amylase inhibition was found from the Lineweaver-Burk plot as mixed noncompetitive. The KM and Vmax were determined as 0.2043 mM and 0.1282 mM/min respectively. In contrast, KM for the control were 0.1537mM and Vmax of 0.09750 mM/min. The inhibition property of A. nobilis could be attributed to its phytochemicals such as flavonoids, saponins, alkaloids, tannins, and terpenoids that were present.
Conclusion: Anthocleista Nobilis leaf extract contains certain naturally occurring anti-diabetic compounds and could be explored for treating type 2 diabetic patients. These findings, however, need further work to validate the exact bioactive constituents responsible for the inhibitory effect.
Study of Selenoprotein P as a Marker of Hepatocellular Carcinoma Diagnosis and Therapeutic Intervention Outcome
Authors: Elqatary Yara Mohamed , Shehata Mona Ahmed Helmy , Elenein Amany Mohamed Abo , Ali Lobna Ahmed Fahmy Abo 
Published: May 2022

Background: Hepatocellular carcinoma is the main public health issue on a global scale, and its diagnosis remains difficult. HCC is now believed to be a common malignancy and a foremost cause of death in Egypt, owing to the high prevalence of cirrhosis associated with chronic HCV. Its incidence has increased in recent years, and it is expected that there will be continuous a rise in the number of occurrences. This study aimed to evaluate the role of serum selenoprotein P as a marker for diagnosis and follow up of therapeutic intervention outcome in hepatocellular carcinoma patients.
Methods: This was a prospective study that took place in Tropical medicine department, Tanta university. Seventy patients with cirrhosis of the liver were included, either with or without hepatocellular carcinoma. The studied patients were divided into group I A of 20 HCC patients who underwent HCC therapeutic intervention, those patients were evaluated before and after their therapeutic intervention, group I B of 25 HCC patients who did not undergo HCC therapeutic intervention as unsuitable and group II of 25 patients with liver cirrhosis as controls
Results: Selenoprotein P was decreased significantly in group IB than group IA and group II (P <0.001) and was significantly decreased in group IA than group II (P <0.001). At cut-off <11 ng/ml selenoprotein P can differentiate between HCC and liver cirrhosis with 80% sensitivity, 76% specificity, 85.7% PPV, 67.9% NPV and 0.851 AUC. After therapeutic intervention, increased serum level of selenoprotein P can be an indicator of good response to treatment. While decreased serum selenoprotein P level can be an indicator of poor response (P <0.001).
Conclusions: Serum selenoprotein P could be useful as a possible diagnostic biomarker for HCC. Detecting that biomarker in serum is a simple, non-invasive procedure that is more realistic than measuring it in tissue samples procured only through procedures that are invasive. Selenoprotein P could be used as a predictive marker of better therapeutic intervention outcome in hepatocellular carcinoma patients. Additionally, our findings imply that Se may be utilised as a supportive treatment for HCC by influencing the level of selenoprotein P.
Efficacy of Direct Acting Anti-Viral Agents in Patients Infected with Chronic Hepatitis C Virus: A Single Center Experience
Authors: Ahsam Salman , Kumar Sanjay Kirshan , Semejo Khadim Hussain , Lail Ghulamullah , Hanif Farina , Luck Nasir Hassan 
Published: May 2022

Background: Hepatitis virus C (HCV) infection is affecting millions of people globally with an estimated prevalence in Pakistan ranging from 4.5 to 8%. Advent of oral direct acting antiviral agents (DAAs) in combination therapy has made possible the treatment of decompensated cirrhosis secondary to hepatitis C (HCV) infection. Therefore, this study focused to evaluate safety and efficacy of direct antiviral agents (DAAs) in compensated and decompensated cirrhotic patients.
Materials and Methods: This cross sectional study was conducted in the Department of Hepatogastroenterology, Sindh Institute of Urology and Transplantation (SIUT) Karachi, from 1st September 2017 to 30th June 2018. Patients diagnosed with HCV, presenting in outpatient department were enrolled. All patients received Daclatasavir, Sofosbuvir and Ribavirin combination. Patient without cirrhosis and with cirrhosis received treatment for 12 and 24 weeks, respectively. End of treatment response was taken as primary end point. Statistical analysis was performed by SPSS version 20.0.
Results: Out of 180 patients, 88(48.9%) were male and 92(51.1%) were female, with mean age of 44.59±11.29 years. Majority had genotype 3 i.e., 145(80.6%). In this study population, 97(53.9%) patients were non-cirrhotic and received 3 months treatment while 83(46.1%) cirrhotic patient got 6 months treatment. Post- stratification observed that young patients have better treatment response rate than older individuals (p-=0.031) On the other hand, statistical insignificant association was observed between end of treatment response with regards to gender, duration of treatment, history of hepatic encephalopathy and ascites.
Conclusion: This study concluded that treatment with direct antiviral agents of Hepatitis C virus related chronic liver disease is effectual and has shown equivalent response in cirrhotic and non-cirrhotic patients. Age is an important factor affecting treatment response i.e, better response achieved in patient with less than 45 years.
Helicobacter Pylori Infection in Paediatric Age Group and Recurrent Abdominal Pain
Authors: Khalid Maria , Liaqat Sadaf , Sherazi Sajid Hussain , Rehman Rabeya , Nisar Rabia , Wajahat Hassan 
Published: May 2022

Background: The term ‘recurrent abdominal pain’ or RAP is defined in terms of duration and frequency of pain. The duration is to be defined as: minimum preceding three months, and over this three-month period, minimum3 episodes of pain having severe intensity causing impairment to perform the daily activities by the affected patients. Over many years, more and more organic causes have been identified because of various advances and better knowledge as well as better investigations tools. The commonest cause of RAP in paediatric age group is found to be H. Pylori infection and it is also treatable.
Objective: To find out helicobacter pylori infection frequency in paediatric age group with recurrent abdominal pain.
Study Design: Cross sectional study.
Place and Duration of Hospital: Pediatrics, DHQ teaching hospital Sargodha from 10th June 2018 to 9th December 2018.
Methodology: One hundred children with recurrent abdominal pain were selected using non probability consecutive sampling. H. Pylori serology was done and results presented.
Results: The mean age was 7.28±2.6 years. H. pylori infection was seen in 27%. More patients belonged to middle socio economic status.
Conclusion: Recurrent abdominal pain in paediatric age group is caused commonly by H. pylori infection and it is easily treatable if detected in early stages.
Virtual patient‐specific QA with DVH‐based metrics
Authors: Lay Lam M. , Chuang Kai‐Cheng , Wu Yuyao , Giles William , Adamson Justus 
Published: May 2022

AbstractWe demonstrate a virtual pretreatment patient‐specific QA (PSQA) procedure that is capable of quantifying dosimetric effect on patient anatomy for both intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT). A machine learning prediction model was developed to use linear accelerator parameters derived from the DICOM‐RT plan to predict delivery discrepancies at treatment delivery (defined as the difference between trajectory log file and DICOM‐RT) and was coupled with an independent Monte Carlo dose calculation algorithm for dosimetric analysis. Machine learning models for IMRT and VMAT were trained and validated using 120 IMRT and 206 VMAT fields of prior patients, with 80% assigned for iterative training and testing, and 20% for post‐training validation. Various prediction models were trained and validated, with the final models selected for clinical implementation being a boosted tree and bagged tree for IMRT and VMAT, respectively. After validation, these models were then applied clinically to predict the machine parameters at treatment delivery for 7 IMRT plans from various sites (61 fields) and 10 VMAT multi‐target intracranial radiosurgery plans (35 arcs) and compared to the dosimetric effect calculated directly from trajectory log files. Dose indices tracked for targets and organs at risk included dose received by 99%, 95%, and 1% of the volume, mean dose, percent of volume receiving 25%–100% of the prescription dose. The average coefficient of determination (r2) when comparing intra‐field predicted and actual delivery error was 0.987 ± 0.012 for IMRT and 0.895 ± 0.095 for VMAT, whereas r2 when comparing inter‐field predicted versus actual delivery error was 0.982 for IMRT and 0.989 for VMAT. Regarding dosimetric analysis, r2 when comparing predicted versus actual dosimetric changes for all dose indices was 0.966 for IMRT and 0.907 for VMAT. Prediction models can be used to anticipate the dosimetric effect calculated from trajectory files and have potential as a “delivery‐free” pretreatment analysis to enhance PSQA.
A new Gaussian–Student's t mixing distribution‐based Kalman filter with unknown measurement random delay rate
Authors: Shan Chenghao , Zhou Weidong , Yang Yefeng , Shan Hanyu 
Published: May 2022

SummaryIn this article, a new Gaussian–Student's t mixing distribution‐based Kalman filter is presented to investigate the filtering issue for linear stochastic system with unknown measurement random delay rate and non‐stationary heavy‐tailed measurement noise. Firstly, by employing a Bernoulli distributed variable and introducing system state extension method, the form of measurement likelihood function of double measurement noise distributions is converted from the weighted sum to an exponential product. Secondly, the non‐stationary heavy‐tailed measurement noises of current time and last time are modeled as Gaussian–Student's t mixing distributions by introducing extra Bernoulli distributed variables. Thirdly, the variational Bayesian technique is utilized to jointly infer the system state, the Bernoulli distributed variables of measurement noises, distribution mixing probabilities, the intermediate random variables, the Bernoulli distributed variable of measurement delay and the unknown measurement random delay rate. Finally, the effectiveness of the proposed Kalman filter is demonstrated by a target tracking simulation experiment.
Understanding the Site‐Selective Electrocatalytic Co‐Reduction Mechanism for Green Urea Synthesis Using Copper Phthalocyanine Nanotubes
Authors: Mukherjee Jit , Paul Sourav , Adalder Ashadul , Kapse Samadhan , Thapa Ranjit , Mandal Sumit , Ghorai Biswajit , Sarkar Sougata , Ghorai Uttam Kumar 
Published: May 2022

AbstractGreen synthesis of urea under ambient conditions by electrochemical co‐reduction of N2 and CO2 gases using effective electrocatalyst essentially pushes the conventional two steps (N2 + H2 = NH3 and NH3 + CO2 = CO(NH2)2) industrial process at high temperature and high pressure, to the brink. The single step electrochemical green urea synthesis process has hit a roadblock due to the lack of efficient and economically viable electrocatalyst with multiple active sites for dual reduction of N2 and CO2 gas molecules to urea. Herein, copper phthalocyanine nanotubes (CuPc NTs) having multiple active sites (such as metal center, Pyrrolic‐N3, Pyrrolic‐N2, and Pyridinic‐N1) as an efficient electrocatalyst which exhibits urea yield of 143.47 µg h–1 mg–1cat and faradaic efficiency of 12.99% at –0.6 V versus reversible hydrogen electrode by co‐reduction of N2 and CO2 are reported. Theoretical calculation suggests that Pyridinic‐N1 and Cu centers are responsible to form CN bonds for urea by co‐reduction of N2 to NN* and CO2 to *CO, respectively. This study provides the new mechanistic insight about the successful electro‐reduction of dual gases (N2 and CO2) in a single molecule as well as rational design of efficient noble metal‐free electrocatalyst for the synthesis of green urea.
Programmable Controlling of Multiple Spatial Harmonics via a Nonlinearly Phased Grating Metasurface
Authors: Tian Han Wei , Zhang Xin Ge , Jiang Wei Xiang , Li Xin , Liu Yuan Ke , Qiu Cheng‐Wei , Cui Tie Jun 
Published: May 2022

AbstractBy modulating physical characteristics (amplitude, phase, polarization, etc.) at the subwavelength scale, metasurfaces have shown prominence in controlling electromagnetic waves. However, metasurfaces with linear phase distributions face difficulties in various wavefront reconstructions intentionally and efficiently, and complex‐amplitude metasurfaces with independent amplitude and phase modulations are preferable. Here, a new scheme of the reprogrammable nonlinearly‐phased grating metasurface, comparable to complex‐amplitude metasurfaces, enabling real‐time and versatile control of multiple spatial harmonics by modulating the phase is reported. Through elaborate and instantaneous programming of nonlinear phase distributions at the metasurface interface, desired electromagnetic wavefronts can be reconstructed in real‐time by reconfiguring the generation and suppression of multiple spatial harmonics and by customizing reflection angles and reflection intensities of each spatial harmonic. To corroborate this design, generation and suppression, intensity tailoring, and retro‐reflection of multiple spatial harmonics are presented and verified experimentally. This work provides a real‐time and efficient way to implement dynamical reconstruction of various electromagnetic wavefronts and can be further applied to other potential scenarios such as holography, imaging, and wireless communication.
Liquid Film Sculpture via Droplet Impacting on Microstructured Heterowettable Surfaces
Authors: Chu Fuqiang , Ni Zhongyuan , Wen Dongsheng , Feng Yanhui , Li Shaokang , Jiang Lei , Dong Zhichao 
Published: May 2022

AbstractLiquid manipulation plays an increasingly critical role in daily life and future technological processes. Although intensive attention is paid on controlling droplets, how to manipulate the behavior of larger scale liquid film still remains mysterious. Here, a droplet‐impact‐induced liquid film sculpture strategy is demonstrated on a microstructured heterowettable surface that can precisely sculpt a liquid film into any graphic pattern. The fundamental principles of the liquid film sculpture are elucidate and a phase diagram is drawn to distinguish three liquid film states upon droplet impacting including dewetting, rupture, and nonrupture. To precisely guide the film sculpture, the microstructured heterowettable surface is designed so that water film will naturally rupture at the top of the microstructure after the droplet impact and subsequently dewet into desired pattern. Liquid film sculpture is accompanied by self‐propulsion and high construction speed, both of which are preferred in no‐spray printing, painting, cleaning, and drawing, inspiring future artistic and engineering applications.
Modulated Photoluminescence of Single‐Layer MoS2 via Nanostructured SrTiO3 Surface
Authors: Huang Chenxi , Chen Chen , Wang Wenyuan , Fu Jun , Xiang Miaomiao , Xing Yue , Chen Qi , Zeng Hualing , Shao Xiang 
Published: May 2022

AbstractThe structure and morphology of the substrate surface play critical roles in tuning the properties of the supported two‐dimension materials (2DM). In this work, a simple strategy to engineer the SrTiO3 single crystal into a trenched structure which is composed of atomically flat terraces and high steps of several nanometers is developed. Through the conventional chemical vapor deposition method, high quality single‐layered MoS2 nanosheets are successfully fabricated directly on the trenched SrTiO3 (Tr‐STO) substrate, which thus result in a heterostructure with well‐defined interface and controllable corrugated morphology. The corrugated MoS2/Tr‐STO sample displays a drastically suppressed photoluminescence as compared to those grown on atomically flat substrates. Detailed scanning probe microscopy in combination with optical spectroscopy measurements demonstrates that the photoluminescence quenching occurs exclusively in the MoS2 area carpeting the high SrTiO3 steps, which can be attributed to the significantly reduced bandgaps hence massively enriched free charges in these regions. This work not only provides a new strategy to tailor the 2DM properties by simply engineering the substrate surface corrugations, but also brings deep insights into the dependence of properties of the hybridized system on the interface morphologies.
Atomic Layer Engineering of Aluminum‐Doped Zinc Oxide Films for Efficient and Stable Perovskite Solar Cells
Authors: Kruszyńska Joanna , Ostapko Jakub , Ozkaya Veysel , Surucu Belkis , Szawcow Oliwia , Nikiforow Kostiantyn , Hołdyński Marcin , Tavakoli Mohammad Mahdi , Yadav Pankaj , Kot Małgorzata , Kołodziej Grzegorz Piotr , Wlazło Mateusz , Satapathi Soumitra , Akin Seckin , Prochowicz Daniel 
Published: May 2022

AbstractAtomic layer deposition (ALD) has been considered as an efficient method to deposit high quality and uniform thin films of various electron transport materials for perovskite solar cells (PSCs). Here, the effect of deposition sequence in the ALD process of aluminum‐doped zinc oxide (AZO) films on the performance and stability of PSCs is investigated. Particularly, the surface of AZO film is terminated by diethylzinc (DEZ)/H2O (AZO‐1) or trimethylaluminum (TMA)/H2O pulse (AZO‐2), and investigated with surface‐sensitive X‐ray photoelectron spectroscopy technique. It is observed that AZO‐2 significantly enhances the thermal stability of the upcoming methylammonium lead iodide (MAPbI3) layer and facilitates charge transport at the interface as evidenced by photoluminescence spectroscopes and favorable interfacial band alignment. Finally, planar‐type PSC with AZO‐2 layer exhibits a champion power conversion efficiency of 18.09% with negligible hysteresis and retains 82% of the initial efficiency after aging for 100 h under ambient conditions (relative humidity 40 ± 5%). These results highlight the importance of atomic layer engineering for developing efficient and stable PSCs.
Investigation and Modeling of the Electrical Bias Stress in Electrolyte‐Gated Organic Transistors
Authors: Segantini Matteo , Ballesio Alberto , Palmara Gianluca , Zaccagnini Pietro , Frascella Francesca , Garzone Giovanna , Marasso Simone Luigi , Cocuzza Matteo , Parmeggiani Matteo 
Published: May 2022

AbstractElectrolyte‐gated organic transistors (EGOTs) are emerging as an important tool in advanced biosensing applications. However, their widespread exploitation is still limited by their poor operational stability. In order to understand the causes of this unreliability, the proposed study focuses on the influence of electrical bias stress (EBS) on EGOTs operating in aqueous electrolytes. Poly(3‐hexylthiophene) (P3HT)‐ and poly[3‐(5‐carboxypentyl)thiophene)] (P3CPT)‐based transistors are studied under the application of a bias in the continuous and pulse mode. Combining electrical and spectroscopic characterizations, it is possible to ascribe the performance variation of P3HT devices to backbone rearrangements induced by side chain oxidation, hydration, and interfacial electrochemical doping at the semiconductor/electrolyte interface, while the presence of polar side chains in P3CPT enhances the oxidative degradation of the polymer throughout the bulk of the film. The charge‐trapping model based on a stretched exponential is commonly exploited for the description of EBS in solid dielectric organic field‐effect transistors (OFETs). The same model is here applied to fit liquid dielectric EGOT behavior. The extracted material parameters are in good agreement with those found in the literature for P3HT‐based OFETs. Finally, a novel improvement of the model is proposed to allow reproducing P3CPT data by accounting for its different degradation process.
Combining Experimental and Theoretical Techniques to Gain an Atomic Level Understanding of the Defect Binding Mechanism in Hard Carbon Anodes for Sodium Ion Batteries
Authors: Surta T. Wesley , Koh Edward , Li Zhifei , Fast Dylan B. , Ji Xiulei , Greaney P. Alex , Dolgos Michelle R. 
Published: May 2022

AbstractSodium ion batteries (NIBs) are an attractive alternative to lithium‐ion batteries in applications that require large‐scale energy storage due to sodium's high natural abundance and low cost. Hard carbon (HC) is the most promising anode material for NIBs; however, there is a knowledge gap in the understanding of the sodium binding mechanism that prevents a rational design of HC. This study tunes sucrose‐derived HC via synthesis temperature then evaluates the structural, physical, and electrochemical properties. Neutron total scattering is used to generate structural models by fitting pair distribution functions (PDF) with a combination of molecular dynamics and reverse Monte Carlo methods. From this model, the number and type of structural features are identified, quantified, and correlated to the galvanostatic charge/discharge. A method of PDF “fingerprinting” binding sites using Na probe atoms is developed and analyzing these PDFs reveals an atomistic view of ion binding sites responsible for “defect” storage mechanisms. Combining these techniques results in an atomic‐level study that provides a big picture of the Na‐binding mechanism in NIBs, which allows for more precise tuning of the structure–property relationships in the future. The methodologies developed will also enable new strategies for the analysis of amorphous functional materials.