bluuebunny/crossref_metadata_2025 huggingface dataset:
Silver nanoparticles biosynthesis using an airborne fungal isolate, Aspergillus flavus: optimization, characterization and antibacterial activity
Authors: Al-Soub Aram , Khleifat Khaled , Al-Tarawneh Amjad , Al-limoun Muhamad , Alfarrayeh Ibrahim , Sarayreh Ahmad Al , Qaisi Yaseen Al , Qaralleh Haitham , Alqaraleh Moath , Albashaireh Anas
Published: August 2022

Background and Objectives: Nanoscience is one of the most important branches of modern science, which deals with the knowledge, structure, and properties of nanoparticles. This study aimed to investigate the ability of an airborne fun- gus (Aspergillus flavus) to synthesize silver nanoparticles (AgNPs) and to test the antibacterial activity of the synthesized AgNPs.
Materials and Methods: The confirmation of AgNPs synthesis and the characterization of their properties were done using UV-Vis spectrophotometer, Zeta potential, Zeta sizer, FT-IR, and XRD analyses. The antibacterial activity was determined using broth microdilution method.
Results: The findings showed that the average diameter of the resultant AgNPs was 474.2 nm with a PDI value of 0.27, and the zeta potential was -33.8 mV. Transmission electron microscopy (TEM) revealed that the AgNPs were regular and spherical in shape. TEM micrographs demonstrated that the AgNPs were smaller than those that were observed by DLS examination because the drying process resulted in particle shrinkage. The average size of AgNPs were less than 35 nm. The AgNPs exhibited a remarkable antibacterial activity against K. pneumoniae, E. coli, E. cloacae, S. aureus, S. epidermidis, and Shigella sp., and the MIC values ranged from 25 to 100 µg/mL. However, an exception was P. aeruginosa in which its MIC was >125 µg/mL.
Conclusion: The results suggest that, the biosynthesized AgNPs by A. flavus could be utilized as a source of potent antibac- terial agents in medicine and biotechnological applications.
Characterization by polyphasic approach of some indigenous halophilic archaea of Djelfa’s rock salt “Hadjr el Meelh”, Algeria
Authors: Beddal Amira , Boutaiba Saad , Laassami Affaf , Hamaidi Fella , Enache Madalin
Published: August 2022

Background and Objectives: Hadjr El Melh of Djelfa is an example of hypersaline ecosystems, which can harbor a wide variety of microorganisms under hostile physicochemical conditions. Given the importance of the study of halophilic mi- croorganisms present there in terms of fundamental and applied microbiology, the purpose of this study was to characterize some halophilic archaea isolated from the brines of this environment.
Materials and Methods: Eight water samples were chosen randomly and collected for physicochemical and microbiolog- ical analyses. Isolation of halophilic archaea was carried out by membrane filter technique. Ten strains were identified by polyphasic approach and tested for enzymes production.
Results: Water samples of Djelfa’s rock salt were slightly acidic to neutral in pH (6.55-7.36) with salinity ranging from 258.68 g/l to 493.91 g/l. Phenotypic, biochemical, taxonomic and phylogenetic characteristics indicated that all strains were classified within the family of Halobacteiaceae. Based on the comparison of DNA sequences encoded 16S rRNA, it was determined that seven strains were affiliated to the genus Haloarcula, two strains were related to the genus Halobacterium and one strain within the genus Haloferax. Production of different enzymes such as protease, amylase, esterase, lipase, leci- thinase, gelatinase and cellulase on solid medium indicated that one strain (S2-2) produced amylase, esterase, lecithinase and protease. However, no strains showed cellulolytic or lipolytic activity. Gelatinase was found in all tested strains.
Conclusion: This report constitutes the first preliminary study of culturable halophilic archaea recovered from the brines of Djelfa’s rock salt with a promising enzymatic potential in various fields of biotechnology.
Assessment of influenza A (H1N1, H3N2) oseltamivir resistance during 2017-2019 in Iran
Authors: Gholami Amytis , Shafiei-Jandaghi Nazanin Zahra , Ghavami Nastaran , Tavakoli Forough , Yavarian Jila , Mokhtari-Azad Talat
Published: August 2022

Background and Objectives: Neuraminidase inhibitors (NAIs) as an imperative antiviral for influenza prophylaxis and treatment are being consumed worldwide. Increasing use of these antivirals might be associated with drug resistance. Re- garding the significance of these variations, this study aimed to investigate the mutations occurring in the NA gene of influ- enza A viruses leading to oseltamivir resistance during 2017-2019 in Iran.
Materials and Methods: In this cross-sectional study, 40 influenza A (H1N1, H3N2) strains, isolated in National Influenza Center (NIC) from patients with Severe Acute Respiratory Infection (SARI) during 2017-2019 were subjected to RT-PCR and sequencing of NA complete gene. The frequency of oseltamivir resistance and variation of NA amino acids in these strains were investigated.
Results: No significant mutation conferring oseltamivir resistance was detected. However, NA antigenic sites in these strains depicted minor changes compared to the vaccine strains. Among H3N2 isolates, mutations at 329, 344, 346 and 385 and among H1N1 isolates mutations at 143 and 188 residues occurred in NA antigenic regions.
Conclusion: Evaluation of NA gene sequences, showed no resistant viruses to oseltamivir. Given that the viruses in the pres- ent study were the last viruses circulating in Iran before COVID-19 pandemic, the results will be beneficial to have a worthy comparison with the strains circulating after the pandemic. Constant monitoring for the emergence of drug-resistant variants and antigenic changes are crucial for all countries.
Evaluation of the association between human herpes virus 6 (HHV-6) and Hashimoto's thyroiditis
Authors: Darvish Molla Zahra , Kalbasi Saeed , Kalantari Shirin , Bidari Zerehpoosh Farahnaz , Shayestehpour Mohammad , Yazdani Shaghayegh
Published: August 2022

Background and Objectives: Hashimoto's thyroiditis is a chronic inflammation and an autoimmune disease of the thyroid gland that causes hypothyroidism. Genetic, internal, and environmental factors are the causes of this disease. Because human herpes viruses such as herpesvirus type 6 (HHV-6) are involved in some autoimmune disorders, they may also play a role in causing this disease. This study aimed to evaluate the association between human herpes virus 6 (HHV-6) with Hashimoto's thyroiditis.
Materials and Methods: In the present study, 64 samples of thyroid paraffin tissue including 32 samples of thyroid paraffin tissue of healthy individuals as control, and 32 samples of thyroid paraffin tissue of Hashimoto's thyroiditis patients were taken from the pathology department of Loghman Hakim Hospital in Tehran. A questionnaire collected demographic infor- mation of patients. After DNA extraction from the samples, the nested-PCR technique was performed using specific primers for HHV-6.
Results: Totally, the HHV6-DNA was found in 34.4% of thyroid tissues of healthy individuals (81.8% female and 18.2% male) and 46.9% of patients with Hashimoto's thyroiditis (73.3% female and 26.7% male). It was found that this difference in virus frequency between the two groups was not statistically significant (P value=0.309). There was also no statistically significant relationship between the prevalence of human herpesvirus type 6 and age or sex.
Conclusion: Based on the present study, the number of HHV-6-infected individuals in Hashimoto's patients and controls did not differ significantly; therefore, HHV-6 appears not to be associated with Hashimoto's thyroiditis.
Molecular study and antifungal susceptibility profile of Trichophyton rubrum and Trichophyton mentagrophytes strains isolated from lesions of humans and cattle
Authors: Mohammadifard Hassan , Amini Kumarss , Bayat Mansour , Hashemi Seyyed Jamal , Noorbakhsh Fatemeh
Published: August 2022

Background and Objectives: Monitoring of contagious diseases is important to advance our knowledge of their epidemi- ology and to enable more impressive investigation and prevention efforts. This study aimed to examine antifungal drug sus- ceptibility and molecular analysis of clinical isolates of Trichophyton rubrum and Trichophyton mentagrophytes in humans and cattle.
Materials and Methods: A total of 400 patients and 500 cattle were evaluated in this study. Dermatophytosis was confirmed in cases by direct microscopy and culture methods. Antifungal drug susceptibility profiles, MIC , and MIC of isolates were 50 90 determined using the broth microdilution method. Multiplex-PCR, RAPD PCR, and sequencing methods were used for the genetic analysis of virulence genes and the ITS1 and ITS2 regions, respectively.
Results: A total of 175 patients and 120 cattle were diagnosed with dermatophytosis. Dermatophytes showed a remarkable rate (30%) of terbinafine resistance. T. mentagrophytes showed lower susceptibility than T. rubrum (MIC=16 μg/mL). Strains harboring Mep1, Mep2, and Mep4 genes had the highest frequency among all genotypes. A RAPD-PCR dendrogram divided T. mentagrophytes and T. rubrum strains into three and six groups, respectively.
Conclusion: A notable rate of resistance to terbinafine in isolated dermatophytes was reported in this study. Examination of RAPD-PCR results showed that T. rubrum strains had higher genetic diversity than T. mentagrophytes. Genetic monitoring of dermatophytes must be considered an important factor in providing fungal infection prevention and treatment approaches.
Pesticide distribution and ecotoxicological risk in the Ayuquila-Armería river
Authors:   Universidad de Guadalajara, Rodríguez-Aguilar Brian Arturo , Martinez-Rivera Luis Manuel ,   Universidad de Guadalajara, Muñiz-Valencia Roberto ,   Universidad de Colima, Mercado-Silva Norman ,   Universidad Autónoma del Estado de Morelos, Iñiguez-Dávalos Luis Ignacio ,   Universidad de Guadalajara, Peregrina-Lucano Alejandro Aarón ,   Universidad de Guadalajara
Published: August 2022

Pesticides make an important contribution to increased global agricultural production; however, their intensive use represents a risk to biota in both the short and long terms. The physical and chemical characteristics of these compounds, as well as their versatility in agricultural, domestic, and public health use, have led them to become widely present in the environment. The objectives of this study were to evaluate the spatiotemporal distribution of pesticides in the surface water of the Ayuquila-Armería river and to conduct an ecotoxicological risk assessment in algae, macroinvertebrates, and fish. The presence of 11 analytes was determined, being λ-cyhalothrin, ametrine, and malathion the pesticides with highest concentrations, and carbendazim, malathion, and glyphosate those with the highest frequency of detection (> 70 %). The number of pesticides detected per sample presented no significant temporal differences, and there was no significant effect of the crops or vegetation adjacent to the study sites on the number of pesticides detected per sample. The sampling conducted in November 2019 (wet season) presented the greatest difference in concentrations of most pesticides, compared to the other samplings. The ecotoxicological risk assessment showed that the macroinvertebrates (Daphnia magna) are the most vulnerable to the concentrations of pesticides in surface water, followed by fish and algae. Regulation of the importation, trade, and management of malathion and λ-cyhalothrin is crucial in order to reduce the presence of their residues and the risks associated with them.
A Complete Proof Of The Riemann Hypothesis Based On A New Expression Of $\xi(s)$
Authors: Zhang Weicun
Published: August 2022

A new expression of the completed zeta function $\xi(s)$ is obtained according to the Hadamard product, i.e., $$\xi(s)=\xi(0)\prod_{i=1}^{\infty}\Big{(}\frac{\beta_i^2}{\alpha_i^2+\beta_i^2}+\frac{(s-\alpha_i)^2}{\alpha_i^2+\beta_i^2}\Big{)}^{d_{i}}$$ where $\rho_i=\alpha_i+j\beta_i, \bar{\rho}_i=\alpha_i-j\beta_i$ are complex conjugate zeros of $\xi(s)$, $0<\alpha_i<1$ and $\beta_i\neq 0$ are real numbers, $d_i\geq 1$ are the multiplicities of $\rho_i$, $i$ are natural numbers from 1 to infinity, $\beta_i$ are in order of increasing $|\beta_i|$, i.e., $|\beta_1|\leq|\beta_2|\leq|\beta_3|\leq \cdots$. Then we have, by the functional equation $\xi(s)=\xi(1-s)$, that $$\xi(0)\prod_{i=1}^{\infty}\Big{(}\frac{\beta_i^2}{\alpha_i^2+\beta_i^2}+\frac{(s-\alpha_i)^2}{\alpha_i^2+\beta_i^2}\Big{)}^{d_{i}} =\xi(0)\prod_{i=1}^{\infty}\Big{(}\frac{\beta_i^2}{\alpha_i^2+\beta_i^2}+\frac{(1-s-\alpha_i)^2}{\alpha_i^2+\beta_i^2}\Big{)}^{d_{i}}$$ i.e., $$\prod_{i=1}^{\infty}\Big{(}1+\frac{(s-\alpha_i)^2}{\beta_i^2}\Big{)}^{d_{i}}=\prod_{i=1}^{\infty}\Big{(}1+\frac{(1-s-\alpha_i)^2}{\beta_i^2}\Big{)}^{d_{i}}$$ which, by Lemma 3, is further equivalent to $$(s-\alpha_i)^2=(1-s-\alpha_i)^2 \Leftrightarrow \alpha_i= \frac{1}{2}, \text{with } i\text{ from 1 to infinity.}$$ Thus, we conclude that the Riemann Hypothesis is true.
A Novel GPPAS Model: Guiding the Implementation of Antimicrobial Stewardship in Primary Care Utilising Collaboration between General Practitioners and Pharmacists
Authors: Saha Sajal K. , Thursky Karin , Kong David C. M. , Mazza Danielle
Published: August 2022

Interprofessional collaboration between general practitioners (GPs) and community pharmacists (CPs) is central to implement antimicrobial stewardship (AMS) programs in primary care. This study aimed to design a GP-pharmacist antimicrobial stewardship (GPPAS) model in Australian primary care. A seven-component exploratory study was conducted since 2017 to 2021 to inform a GPPAS model. We generated both secondary and primary evidence through a systematic review, a scoping review, a rapid review, nationwide surveys of Australian GPs and CPs including qualitative components and a pilot study of a GPPAS model. All study evidence was synthesised, reviewed, merged and triangulated to design a prototype GPPAS model using a Systems Engineering Initiative for Patient Safety theoretical framework. Secondary evidence informed effective GPPAS interventions, and primary evidence captured interprofessional issues, challenges and future needs to implement GPPAS interventions by GPs and CPs. A GPPAS model framework involving GP-pharmacist team-based five GPPAS sub-models were successfully designed to foster AMS education, antimicrobial audits, diagnostic stewardship, delayed prescribing, and routine review of antimicrobial prescription by improved GP-CP collaboration. A GPPAS model could be used as a guide to collaboratively optimise antimicrobial use by GPs and CPs. Implementation studies on GPPAS model and sub-models are required to integrate GPPAS model into GP-pharmacist interprofessional care models in Australia.
A New Perspective on Hcl Scavenging at High Temperatures for Reducing the Smoke Acidity of PVC Cables in Fires. I: An Overview of Theory, Test Methods, and the European Union Regulatory Status
Authors: Sarti Gianluca
Published: August 2022

In the European Union (EU), according to the second basic requirement for construction works of Regulation (EU) N°305/2011 (Construction Product Regulation, or CPR), cables permanently installed in buildings must be classified in terms of their reaction to fire, smoke production, flaming droplets, and acidity. The classification is harmonized at the EU level. Nevertheless, every EU country decides what kind of classification a cable must have to be installed in a specific location depending on its fire risk, following the assumption that the higher the fire risk of the area, the higher the fire performance of the cable. According to CPR, the acidity is indirectly assessed by performing EN 60754-2, giving the additional class based on pH and conductivity measurements. Hydrogen chloride (HCl) is one of the gases PVC cables release when they burn. In some applications out of the scope of CPR, acid scavengers are commonly used in special grade PVC compounds to reduce the emission of acidic smoke. In this first part of the paper, the basic concepts of regulations in the EU on acidity are presented, a review of literature on HCl scavenging is given, and an introduction on acid scavenging at high temperatures is outlined. In the following parts, we will enter more detail about the topic with new data, comparing them with some old ones, mainly from a series of conferences held by some Italian compounders between 2019 and 2022. They were supported in their research and dissemination by PVC4cables, the European Council of Vinyl Manufacturers' (ECVM) platform dedicated to the PVC cables value chain.
Using Multivariate Quality Statistic for Maintenance Decision Support in a Bearing Ring Grinder
Authors: Ahmer Muhammad , Sandin Fredrik , Marklund Pär , Gustafsson Martin , Berglund Kim
Published: August 2022

Grinding processes’ stochastic nature poses a challenge in predicting the quality of the resulting surfaces. Post-production measurements for form, surface roughness, and circumferential waviness are commonly performed due to infeasibility in measuring all quality parameters during the grinding operation. Therefore, it is challenging to diagnose the root cause of quality deviations in real-time resulting from variations in the machine’s operating condition. This paper introduces a novel approach to predicting the overall quality of the individual parts. The grinder is equipped with sensors to implement condition-based maintenance and is induced with five frequently occurring failure conditions for the experimental test runs. The crucial quality parameters are measured for the produced parts. Fuzzy c-means (FCM) and Hotelling’s T-squared (T2) have been evaluated to generate quality labels from the multi-variate quality data. Benchmarked random forest regression models are trained using fault diagnosis feature set and quality labels. Quality labels from the T2 statistic of quality parameters are preferred over FCM approach for their repeatability. The model, trained from T2 labels achieves more than 94% accuracy when compared to the measured ring disposition. The predicted overall quality using the sensors’ feature set is compared against the threshold to reach a trustworthy maintenance decision.
On the Practical Point of View of Option Pricing
Authors: Halidias Nikos
Published: August 2022

In this note we describe a new approach to the option pricing problem by introducing the notion of the safe (and acceptable) for the writer price of an option, in contrast to the fair price used in the Black-Scholes model. We study the problem from the practical point of view concerning mainly the over the counter market. This approach is not affected by the number of the underlying assets and is particularly useful for incomplete markets. In the usual Black-Scholes or binomial or some other approaches one assumes that one can invest or borrow at the same risk free rate $r>0$ which is not true in general. Even if this is the case one can immediately observes that this risk free rate is not a universal constant but is different among different people or institutions. So, the fair price of an option is not so much fair! Even worse, concerning all the continuous time models that assumes construction of replicating portfolios, one should reconstruct the portfolio continuously in time! We also define a variant of the usual binomial model trying to give a cheaper safe or acceptable price for the option.
Accessible Consumer Electronics Are Essential to Closing the Gap in Assistive Technology Provision
Authors: Banes David P
Published: August 2022

Estimates by the World Health Authority suggest that 1 billion people do not have access to the assistive technologies they require. Over the past decade, the design of products that empower people with a disability has shifted from specialised and dedicated products designed only for those with a disability to features and functions integrated into cost-effective consumer technologies for the benefit of all. The opportunity for expansion of the availability of such technologies is at risk of being ignored as a result of models of delivery that are founded in medical devices and which have failed to reflect trends in our understanding of technology and the choices and preferences expressed by persons with a disability. This research undertaken suggests that the opportunities of such expansion offer significant benefits to people with a disability and better both economic and social return on investment for authorities.
Pembelajaran online masa pandemi covid-19 berbasis grup whatsapp untuk meningkatkan motivasi belajar
Authors: Wicaksana Ervan Johan , Atmadja Pramana
Published: August 2022

Penelitian ini untuk meningkatkan motivasi belajar siswa secara online pada masa pandemi Covid-19 pada sistem sirkulasi dengan menggunakan model pembelajaran berbasis masalah. Pengumpulan data dalam penelitian ini dilakukan melalui pengisian kuesioner berupa Google Form yang dikirimkan melalui WhatsApp Group. Data berupa skala likert dianalisis secara deskriptif kuantitatif dan kualitatif. Hasil penelitian menunjukkan bahwa penggunaan WhatsApp Group sebagai media pembelajaran online pada materi Sistem Sirkulasi dapat meningkatkan motivasi belajar siswa yang dibuktikan dengan hasil analisis data berdasarkan jawaban siswa pada angket yang telah dibagikan. Menurut mereka, Sistem Peredaran Darah sangat menarik, hal ini dinyatakan oleh 70% siswa yang bersemangat saat mempelajari Sistem Peredaran Darah. Setelah melakukan pembelajaran online melalui WhatsApp Group. 60% siswa memahami materi Sistem Peredaran Darah yang diberikan menggunakan Grup WhatsApp.

 

Online learning during covid-19 pandemic with whatsapp group to improve students' learning motivation. This research is to improve student motivation to learn online during the Covid-19 pandemic on the circulation system using problem-based learning models. The data collection in this study was carried out through filling out a questionnaire in the form of a Google Form that was sent through WhatsApp Group. Data in the form of a Likert scale were analyzed descriptively quantitatively and qualitatively. The results showed that the use of WhatsApp Group as an online learning medium in the Circulation System material can increase student motivation as evidenced by the results of data analysis based on student answers in the questionnaire that has been distributed. According to them, the Circulatory System is very interesting, this is stated by 70% of students who are excited when studying the Circulatory System. After doing online learning through WhatsApp Group. 60% of students understand the Circulatory System material given using WhatsApp Group.
Evidence for Protracted Intracrustal Reworking of Palaeoarchaean Crust in the Pilbara Craton (Mount Edgar Dome, Western Australia)
Authors: Buzenchi Anda , Moreira Hugo , Bruguier Olivier , Dhuime Bruno
Published: August 2022

~3.5-2.8 Ga granitoids from the Pilbara Craton in Western Australia are one of the most ancient and best-preserved records of early processes of continental crust generation. A number of recent studies have focused on the nature of the mantle source from which Pilbara granitoids derived, yet no consensus has been reached on whether the mantle was chondritic or depleted in the Eo/Palaeoarchaean. Here we present integrated whole-rock (major and trace elements) and zircon (U-Pb and Lu-Hf isotopes) data for 10 granitoids sampled across the Mount Edgar Dome, which recorded four main magmatic events between 3.47 and 3.23 Ga. Whole-rock major and trace element analyses suggest that the samples belong to two distinct petrogenetic groups. The first group is akin to the tonalite-trondhjemite-granodiorite (TTG) suite, representing highly fractionated magmas initially formed by partial melting of a basaltic crust. The second group, here classified as granites, is best interpreted by the remelting of a basaltic crust and the addition of more evolved material, and it is striking that TTG-like and granitic magmas occurred coevally in time and space. Overall, both groups were formed through intense intracrustal differentiation processes that lead to the loss of significant geochemical information about their original sources. High-precision Lu-Hf analyses in zircon allow to obtain such information and to trace back the isotopic composition of the Palaeoarchaean mantle. A clear change from superchondritic to subchondritic Hf isotope compositions is observed between 3.47 and 3.23 Ga. The superchondritic Hf isotope composition of the 3.47 Ga old granitoids substantiates derivation from a depleted mantle source that separated from the chondritic mantle prior to 3.8 Ga. The presence of ca. 3.5 Ga old inherited zircons in younger magmas suggests that crustal remelting processes were involved in their generation. We propose that all granitoids investigated in this study had their crustal sources originated from a single mantle–crust differentiation event that occurred at 3.50 Ga. This event resulted in the differentiation, from the same original mantle, of two distinct crustal reservoirs, i.e., a mafic reservoir with a 176Lu/177Hf ratio of 0.023, and a reservoir of intermediate/felsic composition ( 176Lu/ 177Hf=0.013). 3.32-3.31 Ga-old granitoids were produced by remelting of the mafic reservoir, whereas 3.43 and 3.23 Ga granitoids derived from the intermediate/felsic reservoir. Overall, our data suggest that protracted intracrustal remelting processes and differentiation have played a key role in the formation, evolution, and maturation of the building blocks of continents during the Palaeoarchaean.
Research on the Nucleation Mechanism and Early Warning Method of Strain Rockburst in Deep-Buried Tunnel Based on Microseismic Monitoring
Authors: Yu Qun , Bao Chunyan , Jin Shengji , Wang Junxiang
Published: August 2022

In order to discuss the nucleation mechanism of strain rockburst, this paper takes the rockburst section of deep diversion tunnel of Jinping Hydropower Project of Yalong River as the research object. Through the study of microseismic monitoring technology and the regularity of microseismic parameters, as well as combining the qualitative and quantitative analysis, the nucleation process and instability failure mechanism of strain rockburst were revealed, and the internal relationship between microseismic evolution law and rockburst process was explored. The monitoring results and analysis showed that the development process of strain rockburst under engineering disturbance can be divided into three stages: tensile crack initiation and development stage, macroscopic shear crack formation stage, and overall instability stage, respectively. The failure process was mainly that two macroscopic shear cracks caused by tensile failure were connected and developed to the tunnel wall and then formed a closed triangle region. The rock mass in this area appeared plate-like splitting, spalling, and wedge-shaped rock mass ejection at a certain initial velocity, which eventually lead to intense rockburst and overall instability failure. The results also showed that the rockburst failure process under engineering excavation was in good agreement with the traditional syllogism of rockburst. Meanwhile, based on the evolution characteristics of source parameters and statistical parameters, including microseismic energy, moment magnitude, cumulative apparent volume, energy index, and b value, the quantitative interpretation of the source parameter provided significant evidence and insight into characterization of strainbursts. In addition, these parameter fluctuation characteristics can be effectively used as the precursor information and early warning index of strain rockburst failure. The results of this study can provide reference for monitoring and early warning of rockburst in deep tunnel and taking effective prevention and support measures in time.
Experimental Study on the Fracture Toughness of Granite Affected by Coupled Mechanical-Thermo
Authors: Feng Gan , Liu Chen-Bo , Wang Ji-Lan , Tao Ye , Duan Zhi-Pan , Xiang Wei-Ning
Published: August 2022

Hot dry rock geothermal energy is deep geological energy. Its ability to resist fracture is an important basis for effective reconstruction and scientific evaluation of the stability of geothermal reservoirs. Hot dry rock is typically buried deeply, and the reservoir is often in a high-temperature and high stress environment. There have been limited studies conducted on the effect of different three-dimensional stress and temperature on granite fracture toughness. Thereby, herein an experimental study is conducted on the heat treatment of granite under different external loads and temperatures. The variation in fracture toughness of granite with temperature and pressure is studied using a three-point bending fracture mechanics experiment, scanning electron microscope (SEM) observation, and acoustic wave velocity measurement. The results show that under the joint influence of 25 MPa deviator stress and 200 °C temperature, the Mode I, Mixed mode (I + II), and Mode II fracture toughness of granite show a nonlinear change trend of decreasing and increasing. Among the three modes, the change range of Mode I fracture toughness is not more than 10% which is not significant. Contrarily, the degradation effect of rock mechanical properties caused by the joint action of stress and temperature in Mode II and Mixed mode (I + II) is predominant. The maximum range of Mode II fracture toughness is reduced by 22%, whereas the maximum range of Mixed mode (I + II) fracture toughness is reduced by 18%. However, the compression action of three-dimensional stress causes a slight enhancement in granite mechanical properties, wherein the maximum range of Mixed mode (I + II) fracture toughness is increased by 12%. Furthermore, the change of granite’s ability to resist tensile, shear, and composite (tensile + shear) fracture is not coordinated under the joint action of different temperatures and external loads. This may be due to the small deviator stress effect, which is similar to the early loading stage of uniaxial compression. External loads and thermal stress damage occur in the rock along with the compaction of pore cracks. These mechanisms have different dominant positions under varied temperature and three-dimensional stress coupling conditions, resulting in either the enhancement or weakening of the mechanical properties of granite. The results of this experimental study are conducive to gaining an in-depth understanding of the change law of deep rock mechanical properties and the exploration of hot dry rock reservoir reconstruction.
Assessing the Accuracy of Biogenic Content Estimation from Visible Derivative Spectroscopy of Sedimentary Cores from the Western Pacific
Authors: Pan Hui-Juan , Ortiz Joseph D.
Published: August 2022

The biogenic contents of marine sediments, such as carbonate (CaCO3) and organic carbon (TOC), provide important information about past climatic and environmental changes. For sediment cores, such as those found in the marginal seas of the western Pacific, intensive laboratory study takes considerable time and effort. The previous drilling and coring programs have developed nondestructive methods, which require less time and labor, such as those that utilize visible reflectance derivative spectra measured from the surface of sediment samples to estimate downcore biogenic content. Nevertheless, these methods have been shown to be useful only for on-site estimation of downcore samples and are not considered entirely feasible for testing samples collected from regional or larger spatial scales. The present study presents a novel protocol of spectral decomposition utilizing varimax-rotated principal component analysis (VPCA) for estimating biogenic contents of sediment samples at the basin scale. Using two sediment cores from the South China Sea (SCS) separated by 200 kilometers, we evaluated a new protocol by measuring the visible reflectance spectrum and the biogenic content. Based on six VPCA components of first derivative reflectance spectrum measurements and laboratory analyzed biogenic contents of core MD972148, a set of empirical equations for estimating CaCO3, TOC, and opal contents have been established. The equations were tested using data from core MD012396, and the new regression equations provided accurate estimations. Our study demonstrated that our new methods could achieve better estimates due to the improvement of the regression model with a reduced number of independent variables. Further, this study circumvents the limitation of applying empirical equations to sediment cores outside of the calibration range. Our present findings state that with more comprehensive and systematic reflectance spectral data, the new protocol can be used to estimate biogenic content with more regional or spatial precision in future research.
First report on the acute toxicity of Chloroxylenol to the Whirligig beetle, Orectogyrus alluaudi (Coleoptera: Gyrinidae)
Authors: Amusan Babatunde O. , Koleosho Ayorinde Fola , Richard Godswill E.
Published: August 2022

Environmental contamination by xenobiotics is a worldwide phenomenon being mainly caused by human activities and urbanization. The release of harmful substances leaves short and long term effects in the environment. This study assessed the acute toxicological effects of different concentrations of chloroxylenol (PCMX), an active ingredient in most liquid cleaning products, on the whirligig beetle Orectogyrus alluaudi Regimbart, 1889. This was done with the aim of determining the potential lethal effects of the chemical on this aquatic organism. The beetle’s behaviour and swimming pattern were both altered by PCMX before mortality occurred. The 24-h, 48-h, 72-h, and 96-h calculated LC50 values were 21.587, 16.744, 11.638 and 7.819 mg/L, respectively. The mortality of the test organisms increased with increased concentration and extended exposure duration. Thus giving an indication that the toxicity of PCMX to the beetles was time and concentration-dependent. The altered behaviour and swimming pattern in the beetles could be ascribed to physiological responses and disturbances in their nervous coordination due to exposure to PCMX.
Impact of delay due to the first wave of COVID-19 pandemic on elective surgical patients in a tertiary care center: An observational study.
Authors: Abhinaya Reddy , R Vishnu Prasad N
Published: August 2022

Background: To cope with the stress on the health care system caused by Coronavirus disease 2019 (COVID-19), elective services were withheld in most parts of the world for a variable duration. However, delaying elective services for more than a particular duration adversely affects outcomes of the underly disease. This study was conducted to assess the outcome on elective surgical patients due to delay due to withholding elective surgical services caused by the first wave of the COVID-19 pandemic at our institute. Methodology: This prospective observational study included all the patients planned and waiting for elective surgery till the day elective services were withheld at our institution (24th March 2020) due to the COVID-19 pandemic. All benign and malignant patients were followed until the patients were operated on or three months until elective operative services were resumed at our institution to determine the proportion of patients with worsening symptoms, stage progression, and needing emergency procedures or palliative surgery.Results: Breast cancer was the most common cancer among malignancy patients awaiting surgery. Compared to breast cancer, gastrointestinal cancers had a significantly higher proportion of patients with stage progression (61.3% vs 90%, p = 0.016) and mortality (6.5% vs 53.3%, p < 0.001). In benign patients, symptom progression was seen in 45.9% and emergency surgery/procedure was needed in 5.4 % of patients.Conclusion: Even though the so-called elective surgery, postponing these surgeries, particularly cancer surgeries, can compromise the outcomes of the patients if delayed for more than a certain point. Hence the decision to postpone an elective surgery should be cautioned, even during pandemics.
New calculation of calorie content and determining nutritional level from day-to-day intake of food using Image Processing
Authors: J Roopa Jayasingh. , B Nagajayanthi , Neebha Mary , Sagayam Martin , Elngar Ahmed A.
Published: August 2022

One of the most urgent necessities of all individuals is food. Nowadays people mainly focus on diet because of diabetes, and obesity problems. When we have a healthy diet, it leads to a healthy life span. So, this paper gives a solution for this type of common problem. In this paper, we calculate nutritionally and calorie content utilizing image processing, display in the food segmentation and classification process, etc. This is very useful for dieticians despite the reality Ordinary people can benefit from this as well by manipulating their routine food patterns.
Removal of Methylene Blue Dye by Metal Free Adsorption and Photodegradation Method Using Different Reduction Grades of Graphene Oxide
Authors: Mahich Sanju , Saini Yogesh Kumar , Aggarwal Kanika , Kumar Anuj , Kumar Dinesh , Singh Amanpal
Published: August 2022

Organic pollutant and dyes released into the environment by industries have been highly harmful and toxic for humans as well as for the environment. Graphene oxide (GO) and its reduction form, one of the allotropes of carbon family, were investigated for the removal of pollutant dyes. GO nano-powder was synthesized using an improved version of Hummer’s method and further thermally reduced at different temperatures 125, 150, 175, and 200 °C in the vacuum ambient. An intense (002) diffraction peak was observed at 2θ=9.136° for the pristine GO in the X-ray diffraction spectra which is gradually shifted towards the higher angles with the reduction, and it disappeared if the GO sample reduced at 200°C. I D /I G ratio for GO nano-powder in the Raman spectra decreased from 0.94 to 0.76 due to reduction. GO shows a characteristic absorption band at 3395 cm -1 in Fourier transform infra-red spectra corresponding to stretching of hydroxyl (–OH) group, this peak is flattened with the thermal reduction but not eliminated completely. The band gap of pristine GO significantly reduced from 2.31 to 0.73 eV with the reduction as measured by UV-Vis diffuse reflectance spectrophotometer. Dye adsorption and photocatalytic degradation behaviour of the pristine GO and reduced graphene oxides (rGOs) was examined towards methylene blue dye for 10 mg of GO/rGOs powder in 50 ml of 50 ppm solution by UV-Vis absorption spectroscopy. Pristine GO showed potential adsorption capacity and dye was degraded up to 85.78% within 15 minutes and around 97% after 4 hrs. Meanwhile, highest 47.58% photocatalytic degradation of Methylene blue was achieved for the rGO sample reduced at 150°C in the presence of visible light of 100 watt.
Retinal pigment epithelium exhibits cell size, gene expression, and phagocytic activity alterations when exposed to retinoblastoma chemotherapeutics
Authors: Cerna-Chavez Rodrigo , Rozanska Agata , Poretti Giulia , Benvenisty Nissim , Parulekar Manoj , Lako Majlinda
Published: August 2022

Retinoblastoma (Rb) is a rare malignant disorder affecting the developing retina of children under the age of five. Chemotherapeutic agents used for treating Rb have been associated with defects of the retinal pigment epithelium (RPE), such as hyperplasia, gliosis, mottling, and visual acuity. Herein, we have developed two pluripotent stem cell (PSC)-RPE models to assess the cytotoxicity of known Rb chemotherapeutics such as Melphalan, Topotecan, and TW-37. Our findings demonstrate that these drugs alter the RPE cell size, decrease the monolayer barrier's trans-epithelial resistance and affect the cells' phagocytic activity. Our transcriptional analyses demonstrate an altered expression of genes involved in melanin and retinol processing, tight junction and apical-basal polarity pathways in both models. None of the drug treatments applied within the clinical range caused significant cytotoxic effects, changes to the apical-basal polarity, tight junction network or cell cycle. Together, our results demonstrate that although the most commonly used Rb chemotherapeutic drugs do not cause cytotoxicity in RPE, their application in vitro leads to compromised phagocytosis and strength of the barrier function, in addition to changes in gene expression that could alter the visual cycle.
A New Performance Metric Algorithm in Image Filtering
Authors: R Remya , Nirmala M.
Published: August 2022

Denoising play a vital role in image quality analysis and it is regarded as a challenging task. The quality of the image is analysed based on various performance metrics. This paper focuses on the quality metric for image filtered output and the testing is made on various general and medical images. Denoising is performed by various image filtering approaches and the outcome is good for other stages of image processing such as segmentation and image classification. An enhanced Discrete Wavelet Transform (Enhanced DWT) and a novel performance metrics based on logarithmic estimation are proposed for image denoising and analysing the quality of image. Along with the proposed similarity metrics other metrics like PSNR, NAE, and SSIM are consider for the work. The performance analysis is tested on different images like biomedical images, Barbara, cameraman, vegetables, and remote sensing images as well as a natural image. The experimental result shows that the proposed enhanced DWT yields a better result for all the similarity metrics.
Influence of Hydrogeochemical Factors on the Natural Water Systems of Uburu-Okposi area, Lower Benue Trough, Southeastern Nigeria, using Geochemical and Multivariate Statistical Methods
Authors: Tijani Moshood , Owolabi Tunbosun , Obini Nnamdi
Published: August 2022

The influence of hydrogeological processes on water systems of the Uburu-Okposi area, Lower Benue Trough was investigated to understand the interplay between aquifer materials and the water system resulting in its chemical composition modification. Forty (40) water samples (ground and surface sources) were randomly collected and analyzed for their physicochemical properties. Results from in-situ measured physicochemical parameters are pH: 5.29–8.98, EC: 206–6970 us/cm, and TDS: 112–4690 mg/l. Laboratory results shows Na+ as the dominant cation (4.4–4900 mg/l) with Cl− as the dominant anion (14.4–6300 mg/l). The values were indicative of salinization. Factors influencing water chemistry were determined using Saturation Index (SI), Ionic Ratio, and Bivariate plots. 65% of samples had positive Chloro Alkali Index (CAI) ratio suggesting direct base-exchange reaction as a dominant factor governing water chemistry. CAI 1 & 2 large absolute values show cation exchange as a principal influence on groundwater chemistry. Estimated SI showed Dolomite, Calcite, Aragonite, and Magnesite were supersaturated therefore, they influenced water chemistry. Bivariate plots identified Ion Exchange (carbonate and silicate weathering) as another principal influence on water chemistry. Gibbs plot showed 92.5% samples plotted in the rock–water interaction field with 7.5% plotting within the evaporation-precipitation field. Principal Component Analyses (PCA) extracted six components factors, the first three factors accounted for above 50% of the total variation collectively responsible for the hydrochemical processes in the area via water-rock interactions, carbonate dissolution, and ion exchanges. Conclusively, geogenic factors are the major influence on water chemistry in the study area.
Nonzero-sum Stochastic Differential Gamefor Discrete-Time Markovian jump Linearsystem with incomplete transition rates
Authors: Xu Meng , Zhang ChengKe , Li FangChao , Yang Lu
Published: August 2022

This paper investigates the guaranteed cost control problem and guaranteesthe cost Nash equilibrium for discrete-time Markovian jump Linearsystem (MJLS) with incomplete transition rates. By employing matrixinequalities and the free-connection weighting matrix approach, severalsufficient conditions are proposed to ensure the applicability of theguaranteed cost control strategy. Moreover, we provide sufficient conditionsto highlight further the correctness and lower conservativeness ofthe utilized theorems. Ensuring these conditions for the existence of aguaranteed cost Nash equilibrium affords to transform them into an optimizationproblem that simultaneously satisfies a set of BMI and matrixinequalities. Furthermore, to make the results more general, this paperdesigns guaranteed cost Nash equilibrium strategies for multiple players.Finally, two detailed numerical examples validate the paper’s theorems.
Cerebral blood flow alterations in migraine patients with and without aura: an arterial spin labeling study
Authors: Fu Tong , Liu Lindong , Huang Xiaobin , Zhang Di , Gao Yujia , Yin Xindao , Lin Hai , Dai Yongming , Wu Xinying
Published: August 2022

Background
Migraine aura is a transient, fully reversible visual, sensory, or other central nervous system symptom that classically precedes migraine headache. This study aimed to investigate cerebral blood flow (CBF) alterations of migraine with aura patients (MwA) and without aura patients (MwoA) during inter-ictal periods, using arterial spin labeling (ASL).
Methods
We evaluated 88 migraine patients (32 MwA) and 44 healthy control subjects (HC) who underwent a three-dimensional pseudo-continuous ASL MRI scanning. Voxel-based comparison of normalized CBF was conducted between MwA and MwoA. The relationship between CBF variation and clinical scale assessment was further analyzed. The mean CBF values in brain regions showed significant differences were calculated and considered as imaging features. Based on these features, support vector machine (SVM) models were established to differentiate MwA and MwoA under five-fold cross validation. The predictive ability of the SVM models was further tested in an independent sample of 30 migraine patients (10 MwA).
Results
In comparison to MwoA and HC, MwA exhibited higher CBF levels in the bilateral superior frontal gyrus, bilateral postcentral gyrus and cerebellum, and lower CBF levels in the bilateral middle frontal gyrus, thalamus and medioventral occipital cortex (all p values < 0.05). These variations were also significantly correlated with multiple clinical rating scales about headache severity, quality of life and emotion. On basis of these CBF features, the accuracies and areas under curve of the SVM models in the training and testing samples were 84.3% and 0.872, 83.3% and 0.860 in discriminating patients with and without aura, respectively.
Conclusions
In this study, CBF abnormalities of MwA were identified in multiple brain regions, which might help better understand migraine-stroke connection mechanisms and provide evidence for choosing optimal migraine-specific treatment to avoid aura-associated stroke.
Periodic solutions of quaternionicRiccati equations with periodic coecients
Authors: Grigorian Gevorg
Published: August 2022

In this paper we study the conditions, under which the quaternionic Riccati equations have periodic solutions. The obtained result we compare with one recently obtained important one.