bluuebunny/crossref_metadata_2025 huggingface dataset:
Basic Principles (Indicators) for Assessing the Technical and Economic Potential of Developing Arctic Offshore Oil and Gas Fields
Authors: Stroykov Gennady , Vasilev Yurii N. , Zhukov Oleg V.
Published: December 2021

Sustainable development of the Arctic is the main priority of the state policy regarding regional development of the Russian Federation. The study of the Arctic zone of the Russian Federation for the formation of principles, methods and strategies, as well as organizational and economic mechanisms for its sustainable development is topical at present. This article deals with one of the strategic decision-making tools used in the process of implementing the development program for the Russian Arctic, namely, the assessment of the technical and economic potential of the Arctic fields. The purpose of this assessment is to rank the fields according to the priority of their commissioning for a more optimal distribution of costs in the development of Arctic resources. This paper presents the results and methodology of technical and economic potential estimation in general, and the potential of the Arctic oil and gas fields in particular. An analysis of the conceptual apparatus in the field of the evaluation of various types of potential is carried out. The methodology for assessing the technical and economic potential of a field are investigated. The problems arising in the process of such an assessment are revealed. Recommendations for improving the methodology of assessing the technical and economic potential of oil and gas fields in the Arctic are given. The necessity of expanding the list of indicators for assessing the technical and economic potential of these fields, taking into account current trends, has been noted. A list of 10 technical and 26 economic indicators to assess the technical and economic potential of the development of offshore Arctic fields is proposed.
Differential Requirement for the Cell Wall Integrity Sensor Wsc1p in Diploids Versus Haploids
Authors: Hall Allison E. , Lisci Miriam , Rose Mark D.
Published: December 2021

The primary role of the Cell Wall Integrity Pathway (CWI) in Saccharomyces cerevisiae is monitoring the state of the cell wall in response to general life cycle stresses (growth and mating) and imposed stresses (temperature changes and chemicals). Of the five mechanosensor proteins monitoring cell wall stress, Wsc1p and Mid2p are the most important. We find that WSC1 has a stringent requirement in zygotes and diploids, unlike haploids, and differing from MID2’s role in shmoos. Diploids lacking WSC1 die frequently, independent of mating type. Death is due to loss of cell wall and plasma membrane integrity, which is suppressed by osmotic support. Overexpression of several CWI pathway components suppress wsc1∆ zygotic death, including WSC2, WSC3, and BEM2, as well as the Rho-GAPS, BEM3 and RGD2. Microscopic observations and suppression by BEM2 and BEM3 suggest that wsc1∆ zygotes die during bud emergence. Downstream in the CWI pathway, overexpression of a hyperactive protein kinase C (Pkc1p-R398P) causes growth arrest, and blocks the pheromone response. With moderate levels of Pkc1p-R398P, cells form zygotes and the wsc1∆ defect is suppressed. This work highlights functional differences in the requirement for Wsc1p in diploids Versus haploids and between Mid2p and Wsc1p during mating.
The Solvent Dimethyl Sulfoxide Affects Physiology, Transcriptome and Secondary Metabolism of Aspergillus flavus
Authors: Costes Laura H. , Lippi Yannick , Naylies Claire , Jamin Emilien L. , Genthon Clémence , Bailly Sylviane , Oswald Isabelle P. , Bailly Jean-Denis , Puel Olivier
Published: December 2021

Dimethyl sulfoxide (DSMO) is a simple molecule widely used because of its great solvating ability, but this solvent also has little-known biological effects, especially on fungi. Aspergillus flavus is a notorious pathogenic fungus which may contaminate a large variety of crops worldwide by producing aflatoxins, endangering at the same time food safety and international trade. The aim of this study was to characterize the effect of DMSO on A. flavus including developmental parameters such as germination and sporulation, as well as its transcriptome profile using high-throughput RNA-sequencing assay and its impact on secondary metabolism (SM). After DMSO exposure, A. flavus displayed depigmented conidia in a dose-dependent manner. The four-day exposition of cultures to two doses of DMSO, chosen on the basis of depigmentation intensity (35 mM “low” and 282 mM “high”), led to no significant impact on fungal growth, germination or sporulation. However, transcriptomic data analysis showed that 4891 genes were differentially regulated in response to DMSO (46% of studied transcripts). A total of 4650 genes were specifically regulated in response to the highest dose of DMSO, while only 19 genes were modulated upon exposure to the lowest dose. Secondary metabolites clusters genes were widely affected by the DMSO, with 91% of clusters impacted at the highest dose. Among these, aflatoxins, cyclopiazonic acid and ustiloxin B clusters were totally under-expressed. The genes belonging to the AFB1 cluster were the most negatively modulated ones, the two doses leading to 63% and 100% inhibition of the AFB1 production, respectively. The SM analysis also showed the disappearance of ustiloxin B and a 10-fold reduction of cyclopiazonic acid level when A. flavus was treated by the higher DMSO dose. In conclusion, the present study showed that DMSO impacted widely A. flavus’ transcriptome, including secondary metabolism gene clusters with the aflatoxins at the head of down-regulated ones. The solvent also inhibits conidial pigmentation, which could illustrate common regulatory mechanisms between aflatoxins and fungal pigment pathways. Because of its effect on major metabolites synthesis, DMSO should not be used as solvent especially in studies testing anti-aflatoxinogenic compounds.
Invasive Fungal Infections and Targeted Therapies in Hematological Malignancies
Authors: Little Jessica S. , Weiss Zoe F. , Hammond Sarah P.
Published: December 2021

The use of targeted biologic therapies for hematological malignancies has greatly expanded in recent years. These agents act upon specific molecular pathways in order to target malignant cells but frequently have broader effects involving both innate and adaptive immunity. Patients with hematological malignancies have unique risk factors for infection, including immune dysregulation related to their underlying disease and sequelae of prior treatment regimens. Determining the individual risk of infection related to any novel agent is challenging in this setting. Invasive fungal infections (IFIs) represent one of the most morbid infectious complications observed in hematological malignancy. In recent years, growing evidence suggests that certain small molecule inhibitors, such as BTK inhibitors and PI3K inhibitors, may cause an increased risk of IFI in certain patients. It is imperative to better understand the impact that novel targeted therapies might have on the development of IFIs in this high-risk patient population.
Optimal Returns in Indian Stock Market during Global Pandemic: A Comparative Study
Authors: Debnath Pradip , Srivastava Hari Mohan
Published: December 2021

This research is an extension of our previous work [Debnath and Srivastava (2021)]. In that paper, we designed a portfolio based on data taken from National Stock Exchange (NSE), India, during 1 January 2020 to 31 December 2020 and performance of that portfolio in real-life situation was examined during 1 January 2021 to 21 May 2021 assuming investments were made according to the proposed model. We observed that our proposed portfolio was efficient enough in that period to beat the performance of most of the in-demand mutual funds. It was also conjectured that this portfolio would be sustainable post the second wave of COVID-19 in India. In the present paper, our aim is to validate this conjecture. Here, we examine the performance of this portfolio during the period 1 January 2021 to 18 October 2021 using the same previous data set. We also investigate the performance of this portfolio if it was blindly adopted without applying the stock selection methodology during 1 January 2019 to 31 December 2019. Using paired t-test between the difference of means of the performances in the year 2019 and the year 2021, we show that the performance in 2021 was significantly enhanced because of selecting the stocks applying our proposed model.
Sticky Stock Market Analysts
Authors: Filiz Ibrahim , Judek Jan René , Lorenz Marco , Spiwoks Markus
Published: December 2021

Technological progress in recent years has made new methods available for making forecasts in a variety of areas. We examine the success of ex-ante stock market forecasts of three major stock market indices, i.e., the German Stock Market Index (DAX), the Dow Jones Industrial Index (DJI), and the Euro Stoxx 50 (SX5E). We test whether the forecasts prove true when they reach their effective dates and are therefore suitable for active investment strategies. We revive the thoughts of the American sociologist William Fielding Ogburn, who argues that forecasters consistently underestimate the variability of the future. In addition, we draw on some contemporary measures of forecast quality (prediction-realization diagram, test of unbiasedness, and Diebold–Mariano test). We reveal that (a) unusual events are underrepresented in the forecasts, (b) the dispersion of the forecasts lags behind that of the actual events, (c) the slope of the regression lines in the prediction-realization diagram is <1, (d) the forecasts are highly biased, and (e) the quality of the forecasts is not significantly better than that of naïve forecasts. The overall behavior of the forecasters can be described as “sticky” because their forecasts adhere too strongly to long-term trends in the indices and are thus characterized by conservatism.
Support Mechanisms for Canada’s Cultural and Creative Sectors during COVID-19
Authors: Wall-Andrews Charlie , Walker Emma , Cukier Wendy
Published: December 2021

The cultural and creative industries enhance the quality of life for Canadians and visitors to Canada. However, definitions of the sector vary, presenting challenges for researchers and policymakers. Government data shows that the pandemic job and revenue loss were disproportionate in the arts. The Canadian government created a range of financial tools (grants and subsidies) to support the sector during the Pandemic. This paper analyzes these financial instruments created in response to the Pandemic. This paper offers a case study on how government can support the economic and social success of the creative and cultural sector (CCS) in Canada and avoid the risk of the cultural ecosystem collapsing. In addition, the key findings may be helpful in other industries and markets when exploring ways to support the cultural and creative sectors, which are vital components of domestic and tourism activity.
Can We Prescribe the Physical Parameters of Multiple Black Holes?
Authors: Rácz István
Published: December 2021

The parabolic-hyperbolic form of the constraints and superposed Kerr-Schild black holes have already been used to provide a radically new initialization of binary black hole configurations. The method generalizes straightforwardly to multiple black hole systems. This paper is to verify that each of the global Arnowitt-Deser-Misner quantities of the constructed multiple black hole initial data can always be prescribed, as desired, in advance of solving the constraints. These global charges are shown to be uniquely determined by the physical parameters of the involved individual Kerr-Schild black holes.
A Novel Hybrid Approach for Optimal Placement of Non-Dispatchable Distributed Generations in Radial Distribution System
Authors: Prakash Prem , Meena Duli Chand , Malik Hasmat , Alotaibi Majed A. , Khan Irfan Ahmad
Published: December 2021

The objective of the present paper is to study the optimum installation of Non-dispatchable Distributed Generations (NDG) in the distribution network of given sizes under the given scheme. The uncertainty of various random (uncertain) parameters like load, wind and solar operated DG besides uncertainty of fuel prices has been investigated by the three-point estimate method (3-PEM) and Monte Carlo Simulation (MCS) based methods. Nearly twenty percent of the total number of buses are selected as candidate buses for NDG placement on the basis of system voltage profile to limit the search space. Weibull probability density function (PDF) is considered to address uncertain characteristics of solar radiation and wind speed under different scenarios. Load uncertainty is described by Standard Normal Distribution Function (SNDF). To investigate the solution of optimal probabilistic load flow (OPLF) three-point PEM-based technique was applied. For optimization, Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and GA-PSO hybrid-based Artificial Intelligent (AI) based optimization techniques are employed to achieve the optimum value of the multi-objectives function. The proposed multi-objective function comprises loss and different costs. The proposed methods have been applied to IEEE 33- bus radial distribution network. Simulation results obtained by these techniques are compared based on loss minimization capability, enhancement of system bus voltage profile and reduction of cost and fitness functions. The major findings of the present study are the PEM-based method which provides almost similar results as MCS based method with less computation time and as far as loss minimization capacity, voltage profile improvement etc. is concerned, the hybrid-based optimization methods are compared with GA and PSO based optimization techniques.
Flexible Power-Normal Models with Applications
Authors: Martínez-Flórez Guillermo , Gallardo Diego I. , Venegas Osvaldo , Bolfarine Heleno , Gómez Héctor W.
Published: December 2021

The main object of this paper is to propose a new asymmetric model more flexible than the generalized Gaussian model. The probability density function of the new model can assume bimodal or unimodal shapes, and one of the parameters controls the skewness of the model. Three simulation studies are reported and two real data applications illustrate the flexibility of the model compared with traditional proposals in the literature.
Limits of Quantum B-Algebras
Authors: Gan Aiping , Muzammal Aziz , Yang Yichuan
Published: December 2021

Every set with a binary operation satisfying a true statement of propositional logic corresponds to a solution of the quantum Yang-Baxter equation. Quantum B-algebras and L-algebras are closely related to Yang-Baxter equation theory. In this paper, we study the categories with quantum B-algebras with morphisms of exact ones or spectral ones. We guarantee the existences of both direct limits and inverse limits.
Primary School Teachers’ Conceptions about the Use of Robotics in Mathematics
Authors: Seckel María José , Breda Adriana , Font Vicenç , Vásquez Claudia
Published: December 2021

Learning about the conceptions used by primary school teachers towards the use of robotics in class is essential as the first step towards its application in the classroom. Therefore, with the purpose of describing the understanding applied when teaching and learning mathematics use educational robots, research was conducted by means of mixed methods using a descriptive design by survey. Such research consisted of closed questions (Likert-type scale from 1 to 5) and open questions, given to 83 primary school teachers who currently teach students in the first years of school (First to Fourth grade) in two Chilean districts. The results showed that in general, there is a positive predisposition towards the addition of robots in the learning and teaching of mathematic processes during the first years of school, even though teachers claim there is a struggle to incorporate robots in their lessons due to the high number of students and the reduced space in their classrooms.
Impact of the Age of Cecal Material Transfer Donors on Alzheimer’s Disease Pathology in 5xFAD Mice
Authors: Valeri Francesco , dos Santos Guilherme Malena , He Fuqian , Stoye Nicolai M. , Schwiertz Andreas , Endres Kristina
Published: December 2021

Alzheimer’s disease is a progressive neurodegenerative disorder affecting around 30 million patients worldwide. The predominant sporadic variant remains enigmatic as the underlying cause has still not been identified. Since efficient therapeutic treatments are still lacking, the microbiome and its manipulation have been considered as a new, innovative approach. 5xFAD Alzheimer’s disease model mice were subjected to one-time fecal material transfer after antibiotics-treatment using two types of inoculation: material derived from the caecum of age-matched (young) wild type mice or from middle aged, 1 year old (old) wild type mice. Mice were profiled after transfer for physiological parameters, microbiome, behavioral tasks, and amyloid deposition. A single time transfer of cecal material from the older donor group established an aged phenotype in the recipient animals as indicated by elevated cultivatable fecal Enterobacteriaceae and Lactobacillaceae representative bacteria, a decreased Firmicutes amount as assessed by qPCR, and by increased levels of serum LPS binding protein. While behavioral deficits were not accelerated, single brain regions (prefrontal cortex and dentate gyrus) showed higher plaque load after transfer of material from older animals. We could demonstrate that the age of the donor of cecal material might affect early pathological hallmarks of Alzheimer’s disease. This could be relevant when considering new microbiome-based therapies for this devastating disorder.
Advances in Biosynthesis of Natural Products from Marine Microorganisms
Authors: Zhou Quan , Hotta Kinya , Deng Yaming , Yuan Rui , Quan Shu , Chen Xi
Published: December 2021

Natural products play an important role in drug development, among which marine natural products are an underexplored resource. This review summarizes recent developments in marine natural product research, with an emphasis on compound discovery and production methods. Traditionally, novel compounds with useful biological activities have been identified through the chromatographic separation of crude extracts. New genome sequencing and bioinformatics technologies have enabled the identification of natural product biosynthetic gene clusters in marine microbes that are difficult to culture. Subsequently, heterologous expression and combinatorial biosynthesis have been used to produce natural products and their analogs. This review examines recent examples of such new strategies and technologies for the development of marine natural products.
Antibacterial Activities of Prenylated Isoflavones from Maclura tricuspidata against Fish Pathogenic Streptococcus: Their Structure-Activity Relationships and Extraction Optimization
Authors: Lim Jae-Woong , Jo Yang Hee , Choi Ji-Seok , Lee Mi Kyeong , Lee Ki Yong , Kang So Young
Published: December 2021

Streptococcus zoonotic bacteria cause serious problems in aquaculture with clinical effects on humans. A structure-antibacterial activity relationships analysis of 22 isoflavones isolated from M. tricuspidata (leaves, ripe fruits, and unripe fruits) against S. iniae revealed that prenylation of the isoflavone skeleton was an important key for their antibacterial activities (minimum inhibitory concentrations: 1.95–500 μg/mL). Through principal component analysis, characteristic prenylated isoflavones such as 6,8-diprenlygenistein (4) were identified as pivotal compounds that largely determine each part’s antibacterial activities. M. tiricuspidata ripe fruits (MTF), which showed the highest antibacterial activity among the parts tested, were optimized for high antibacterial activity and low cytotoxicity on fathead minnow cells using Box–Behnken design. Optimized extraction conditions were deduced to be 50%/80 °C/7.5 h for ethanol concentration/extraction temperature/time, and OE-MTF showed contents of 6,8-diprenlygenistein (4), 2.09% with a MIC of 40 µg/mL. These results suggest that OE-MTF and its active isoflavones have promising potential as eco-friendly antibacterial agents against streptococcosis in aquaculture.
Optimization Method for Phenolic Compounds Extraction from Medicinal Plant (Juniperus procera) and Phytochemicals Screening
Authors: Salih Abdalrhaman M. , Al-Qurainy Fahad , Nadeem Mohammad , Tarroum Mohamed , Khan Salim , Shaikhaldein Hassan O. , Al-Hashimi Abdulrahman , Alfagham Alanoud , Alkahtani Jawaher
Published: December 2021

Juniperus procera is a natural source of bioactive compounds with the potential of antitumor, antimicrobial, insecticidal, antifungal, and antioxidant activities. An optimization method was developed for total phenolic content (TPC), total flavonoid content (TFC), and total tannin content (TTC) in leaf and seed extract of Juniperus procera. Organic solvents (methanol (99.8%), ethanol (99%), and acetone (99.5%)), and deionized water (DI) were used for extraction. The estimation of TPC, TFC, and TTC in plant materials was carried out using UV-spectrophotometer and HPLC with the standards gallic acid, quercetin, and tannic acid. Recovery of TPC in leaf extract ranged from 2.9 to 9.7 mg GAE/g DW, TFC from 0.9 to 5.9 mg QE/g DW, and TTC ranged from 1.5 to 4.3 mg TA/g DW while the TPC value in the seed extract ranged from 0.53 to 2.6 mg GAE/g DW, TFC from 0.5 to 1.6 mg QE/g DW, and TTC ranged from 0.5 to 1.4 mg TA/g DW. This result revealed that methanol is the best solvent for recovery of the TPC value (9.7 mg) from leaf extract in comparison to other solvents. Ethanol recorded the highest result of TFC (5.9 mg) in leaf extract among the solvents whereas acetone was the best for TTC yield recovery from leaf extract (4.3 mg). In the case of the seed extract, ethanol was the best solvent for both TPC (2.6 mg), and TFC (1.6 mg) recovery in comparison to other solvents. Total tannin content in methanol resulted in significant recovery from seed extract (1.4 mg). Separation and quantification of gallic acid, quercetin, and tannic acid in plant materials were undertaken using HPLC. Gallic acid in leaf and seed of J. procera ranged from 6.6 to 9.2, 6.5 to 7.2 µg/g DW, quercetin from 6.3 to 18.2, 0.9 to 4.2 µg/g DW, and tannic acid from 16.2 to 29.3, 6.6 to 9.3 µg/g DW, respectively. Solvents have shown a significant effect in the extraction of phenolic compounds. Moreover, phytochemicals in plant materials were identified using GC-MS and resulted in very important bioactive compounds, which include anti-inflammatory, antibacterial, and antitumor agents such as ferruginol, phenanthrene, and n-hexadecanoic acid. In conclusion, the optimal solvent for extraction depends on the part of the plant material and the compounds that are to be isolated.
Attenuation of Tumor Development in Mammary Carcinoma Rats by Theacrine, an Antagonist of Adenosine 2A Receptor
Authors: Jhuo Cian-Fen , Hsu Yu-Yu , Chen Wen-Ying , Tzen Jason T. C.
Published: December 2021

Caffeine has been reported to induce anti-tumor immunity for attenuating breast cancer by blocking the adenosine 2A receptor. Molecular modeling showed that theacrine, a purine alkaloid structurally similar to caffeine, might be an antagonist of the adenosine 2A receptor equivalent to or more effective than caffeine. Theacrine was further demonstrated to be an effective antagonist of the adenosine 2A receptor as its concurrent supplementation significantly reduced the elevation of AMPK phosphorylation level in MCF-7 human breast cells induced by CGS21680, an agonist of adenosine 2A receptors. In an animal model, the development of mammary carcinoma induced by 7,12-Dimethylbenz[a]anthracene in Sprague–Dawley rats could be attenuated by daily supplement of theacrine of 50 or 100 mg/kg body weight. Both expression levels of cleaved-caspase-3/pro-caspase-3 and granzyme B in tumor tissues were significantly elevated when theacrine was supplemented, indicating the induction of programmed cell death in tumor cells might be involved in the attenuation of mammary carcinoma. Similar to the caffeine, significant elevation of interferon-γ and tumor necrosis factor-α was observed in the serum and tumor tissues of rats after the theacrine supplement of 50 mg/kg body weight. Taken together, theacrine is an effective antagonist of adenosine 2A receptors and possesses great potential to be used to attenuate breast cancer.
In Vitro Antileishmanial and Antischistosomal Activities of Anemonin Isolated from the Fresh Leaves of Ranunculus multifidus Forsk
Authors: Sirak Betelhem , Asres Kaleab , Hailu Asrat , Dube Mthandazo , Arnold Norbert , Häberli Cecile , Keiser Jennifer , Imming Peter
Published: December 2021

Leishmaniasis and schistosomiasis are neglected tropical diseases (NTDs) infecting the world’s poorest populations. Effectiveness of the current antileishmanial and antischistosomal therapies are significantly declining, which calls for an urgent need of new effective and safe drugs. In Ethiopia fresh leaves of Ranunculus multifidus Forsk. are traditionally used for the treatment of various ailments including leishmaniasis and eradication of intestinal worms. In the current study, anemonin isolated from the fresh leaves of R. multifidus was assessed for its in vitro antileishmanial and antischistosomal activities. Anemonin was isolated from the hydro-distilled extract of the leaves of R. multifidus. Antileishmanial activity was assessed on clinical isolates of the promastigote and amastigote forms of Leishmania aethiopica and L. donovani clinical isolates. Resazurin reduction assay was used to determine antipromastigote activity, while macrophages were employed for antiamastigote and cytotoxicity assays. Antischistosomal assays were performed against adult Schistosoma mansoni and newly transformed schistosomules (NTS). Anemonin displayed significant antileishmanial activity with IC50 values of 1.33 nM and 1.58 nM against promastigotes and 1.24 nM and 1.91 nM against amastigotes of L. aethiopica and L. donovani, respectively. It also showed moderate activity against adult S. mansoni and NTS (49% activity against adult S. mansoni at 10 µM and 41% activity against NTS at 1 µM). The results obtained in this investigation indicate that anemonin has the potential to be used as a template for designing novel antileishmanial and antischistosomal pharmacophores.
Constructing Co3O4/g-C3N4 Ultra-Thin Nanosheets with Z-Scheme Charge Transfer Pathway for Efficient Photocatalytic Water Splitting
Authors: Guo Yuan , Liu Wanqing , Duan Wei , Wang Siyu , Jia Liqun , Zhang Guoqing , Zhu Baolin , Huang Weiping , Zhang Shoumin
Published: December 2021

Photocatalytic water splitting for hydrogen generation is a significant pathway for sustainable energy conversion and production. The photocatalysts with a Z-scheme water splitting charge transfer pathway is superior due to the good separation and migration ability of photoexcited charge carriers. Herein, Co3O4/g-C3N4 photocatalysts with Z-scheme charge transfer pathway were successfully constructed by an electrostatic interaction-annealing method. The as-prepared Co3O4/g-C3N4 ultra-thin nanosheets were tested and analyzed by XRD, EA, ICP, SEM, TEM, AFM, XPS, UV-Vis DRS, PL and photoelectrochemical measurements. Moreover, the influences of fabrication parameters on performance of Co3O4/g-C3N4 catalysts were investigated, and 0.5% Co3O4/g-C3N4 exhibited the optimal activity. Based on the characterization and catalytic performance, the Z-scheme charge transfer pathway of Co3O4/g-C3N4 was established and put forward. To further improve the catalytic performance of Co3O4/g-C3N4, 0.5% Pt was added as a co-catalyst. The obtained Pt/0.5% Co3O4/g-C3N4 was recyclable and remained the original catalytic water splitting performance within 20 h. The modification of Co3O4 and Pt improved the separation and migration of e− and h+, and induced the increased hydrogen evolution rate of g-C3N4.
Performance Analysis of a Multi-Function Mach-Zehnder Interferometer Based Photonic Architecture on SOI Acting as a Frequency Shifter
Authors: Hasan Gazi Mahamud , Hasan Mehedi , Hall Trevor J.
Published: December 2021

A photonic frequency shifter based on generalized Mach-Zehnder interferometer (GMZI) architecture is presented and experimentally validated. The circuit consists of four Mach-Zehnder modulators (MZM) in a 4 × 4 network bounded by two 4 × 4 multimode interference couplers and functionally equivalent to two parallel dual-parallel MZM (DP-MZM). The circuit can offer static bias free operation, virtual connectivity control of the components, and spatial separation of up- and down-converted carriers, which can be collected from separate ports without using any optical demultiplexing filters. Thus, the design permits remote heterodyning (advantages which cannot be obtained using a commercial DP-MZM or filter based optical frequency shifter). Experimental investigation shows deviation from ideal performance due to possible fabrication error and poor fiber-chip coupling. A carrier suppression of >20 dB and spurious sideband suppression >12 dB relative to the principal harmonics is achieved without any tuning for bias adjustment. In addition to the frequency conversion, the integration feasible circuit can also perform as a sub-carrier generator, IQ modulator, and frequency multiplier.
Towards Ultimate High-Power Scaling: Coherent Beam Combining of Fiber Lasers
Authors: Fathi Hossein , Närhi Mikko , Gumenyuk Regina
Published: December 2021

Fiber laser technology has been demonstrated as a versatile and reliable approach to laser source manufacturing with a wide range of applicability in various fields ranging from science to industry. The power/energy scaling of single-fiber laser systems has faced several fundamental limitations. To overcome them and to boost the power/energy level even further, combining the output powers of multiple lasers has become the primary approach. Among various combining techniques, the coherent beam combining of fiber amplification channels is the most promising approach, instrumenting ultra-high-power/energy lasers with near-diffraction-limited beam quality. This paper provides a comprehensive review of the progress of coherent beam combining for both continuous-wave and ultrafast fiber lasers. The concept of coherent beam combining from basic notions to specific details of methods, requirements, and challenges is discussed, along with reporting some practical architectures for both continuous and ultrafast fiber lasers.
Immunoinformatics Analysis of SARS-CoV-2 ORF1ab Polyproteins to Identify Promiscuous and Highly Conserved T-Cell Epitopes to Formulate Vaccine for Indonesia and the World Population
Authors: Gustiananda Marsia , Sulistyo Bobby Prabowo , Agustriawan David , Andarini Sita
Published: December 2021

SARS-CoV-2 and its variants caused the COVID-19 pandemic. Vaccines that target conserved regions of SARS-CoV-2 and stimulate protective T-cell responses are important for reducing symptoms and limiting the infection. Seven cytotoxic (CTL) and five helper T-cells (HTL) epitopes from ORF1ab were identified using NetCTLpan and NetMHCIIpan algorithms, respectively. These epitopes were generated from ORF1ab regions that are evolutionary stable as reflected by zero Shannon’s entropy and are presented by 56 human leukocyte antigen (HLA) Class I and 22 HLA Class II, ensuring good coverage for the Indonesian and world population. Having fulfilled other criteria such as immunogenicity, IFNγ inducing ability, and non-homology to human and microbiome peptides, the epitopes were assembled into a vaccine construct (VC) together with β-defensin as adjuvant and appropriate linkers. The VC was shown to have good physicochemical characteristics and capability of inducing CTL as well as HTL responses, which stem from the engagement of the vaccine with toll-like receptor 4 (TLR4) as revealed by docking simulations. The most promiscuous peptide 899WSMATYYLF907 was shown via docking simulation to interact well with HLA-A*24:07, the most predominant allele in Indonesia. The data presented here will contribute to the in vitro study of T-cell epitope mapping and vaccine design in Indonesia.
Anti-Inflammatory Potential of the Oleoresin from the Amazonian Tree Copaifera reticulata with an Unusual Chemical Composition in Rats
Authors: de Almeida Júnior José , da Silva Éden , Moraes Tânia , Kasper Aline , Sartoratto Adilson , Baratto Leopoldo , de Oliveira Elaine , Oliveira Euzebio , Barata Lauro , Minervino Antonio , Moraes Waldiney
Published: December 2021

Copaifera reticulata Ducke is a popularly known species known as copaíba that is widely spread throughout the Amazon region. The tree yields an oleoresin which is extensively used in local traditional medicine mainly as an anti-inflammatory and antinociceptive agent. The aim of the present study was to assess the anti-inflammatory potential of this oleoresin obtained from a national forest in the central Amazon which presented an unusual chemical composition. The chemical composition of volatile compounds of oleoresin was analyzed by gas chromatography-mass spectrometry. The acute toxicity assay was performed with a single dose of 2000 mg/kg. The anti-inflammatory potential was evaluated by carrageenan-induced paw edema and air pouch assays using four different C. reticulata oleoresin concentrations (10, 100, and 400 mg/kg). The exudate was evaluated for nitrite concentration through the colorimetric method and for TNF-α, IL-1β, and PGE2 by ELISA. C. reticulata oleoresin collected in the Amazonian summer contained six major sesquiterpene compounds (β-bisabolene, cis-eudesma-6,11-diene, trans-α-bergamotene, β-selinene, α-selinene, and β-elemene) and was nontoxic at a dose of 2000 mg/kg, showing low acute toxicity. Different from oleoresin obtained from other sites of the Brazilian Amazon, the major volatile compound found was β-Bisabolene with 25.15%. This β-Bisabolene-rich oleoresin reduced the formation of paw edema induced by carrageenan and reduced the global number of cells in the air pouch assay, as well as exudate volume and nitrite, TNF-α, IL-1β, and prostaglandin E2 levels (p < 0.05). C. reticulata oleoresin with a high β-Bisabolene concentration showed anti-inflammatory activity, reducing vascular permeability and consequently edema formation, and thus reducing cell migration and the production of inflammatory cytokine, confirming its traditional use by local Amazonian communities.
Ischemia-Induced Cognitive Impairment Is Improved via Remyelination and Restoration of Synaptic Density in the Hippocampus after Treatment with COG-Up® in a Gerbil Model of Ischemic Stroke
Authors: Lee Tae-Kyeong , Hong Junkee , Lee Ji-Won , Kim Sung-Su , Sim Hyejin , Lee Jae-Chul , Kim Dae Won , Lim Soon Sung , Kang Il Jun , Won Moo-Ho
Published: December 2021

Cerebrovascular disease such as ischemic stroke develops cognitive impairment due to brain tissue damage including neural loss, demyelination and decrease in synaptic density. In the present study, we developed transient ischemia in the forebrain of the gerbil and found cognitive impairment using the Barnes maze test and passive avoidance test for spatial memory and learning memory, respectively. In addition, neuronal loss/death was detected in the Cornu Ammonis 1 (CA1) region of the gerbil hippocampus after the ischemia by cresyl violet histochemistry, immunohistochemistry for neuronal nuclei and histofluorescence with Fluoro-Jade B. Furthermore, in the CA1 region following ischemia, myelin and vesicular synaptic density were significantly decreased using immunohistochemistry for myelin basic protein and vesicular glutamate transporter 1. In the gerbils, treatment with COG-up® (a combined extract of Erigeron annuus (L.) Pers. and Brassica oleracea Var.), which was rich in scutellarin and sinapic acid, after the ischemia, significantly improved ischemia-induced decline in memory function when compared with that shown in gerbils treated with vehicle after the ischemia. In the CA1 region of these gerbils, COG-up® treatment significantly promoted the remyelination visualized using immunohistochemistry myelin basic protein, increased oligodendrocytes visualized using a receptor-interacting protein, and restored the density of glutamatergic synapses visualized using double immunofluorescence for vesicular glutamate transporter 1 and microtubule-associated protein, although COG-up® treatment did not protect pyramidal cells (principal neurons) located in the CA1 region form the ischemic insult. Considering the current findings, a gerbil model of ischemic stroke apparently showed cognitive impairment accompanied by ischemic injury in the hippocampus; also, COG-up® can be employed for improving cognitive decline following ischemia-reperfusion injury in brains.
Therapeutic physical factors in restorative treatment of patients with nonalcoholic steatohepatitis combined with biliary sludge
Authors: Kaysinova Agnessa Sardoevna , Fedorov Andrey Alekseevich , Vakhaeva Zarema Adamovna , Efimenko Nataliya Viktorovna , Bolatchieva Leila Khyzyrovna , Bolatchiev Anzor Khyzyrovich
Published: December 2021

Purpose of the study. To study the effectiveness of restorative treatment of patients with nonalcoholic steatohepatitis in combination with biliary sludge at the inpatient stage when low-mineralized mineral water and preformed peloid therapy are included in the basic scheme. Material and methods. A total of 119 patients with nonalcoholic steatohepatitis in combination with biliary sludge were observed and distributed into 3 randomized groups: in the main group, 39 patients received basic drug therapy in accordance with the Federal Clinical Recommendations, «Sernovodskaya» mineral water for ingestion and in the form of gallbladder cleanse, and preformed application peloid therapy; in the comparison group, 40people received only pharmacotherapy and balneotherapy, in the control group — pharmacotherapy. The control of the effectiveness of the treatment was carried out according to the dynamics of clinical, biochemical and functional studies. Results. The inclusion of medium-mineralized mineral water «Sernovodskaya» in the form of drinking treatment and cleanse and preformed peloid therapy in the complex of therapeutic measures for patients provides a significant decrease in the intensity of clinical manifestations by 54.4% versus 40% with the use of pharmaco- and balneotherapy and 28,8% — with only drug therapy; cytolysis and cholestasis syndromes — by 46,2; 39,8 and 28.9%, respectively. Restoration of the contractile function of the gallbladder is observed in 78,8% of cases versus 65.6% when using only pharmacotherapy. The duration of hospitalization in the main group was reduced by 3 days, and in the comparison group — by 1,5 days, compared with the indicators in the control group. Conclusion. The developed new medical technology for the treatment of patients with nonalcoholic steatohepatitis in combination with biliary sludge with the combined use of mineral waters and preformed peloid preparations against the background of basic pharmacotherapy at the inpatient stage provides a significant increase in the efficiency of therapeutic measures.
Hidrogeles derivados de acrilamida y ácido itacónico como soporte en medios de cultivo de plántulas de papa
Authors: Contreras Ramírez Jesús Miguel , Juárez Jessica , Jaimez Juan
Published: December 2021

Hidrogeles de poliacrilamida (PAAm) y de poli(acrilamida-co-ácido itacónico) (P(AAm-co-AI)) sintetizados en agua y en una solución acuosa de buffer de fosfato al 0,2 M, fueron usados como soporte en los medios de cultivo de tejido vegetal sistema autotrófico hidropónico (SAH) y cultivo in-vitro con solución nutritiva Murashige-Skoog (MS) para la producción de plántulas de papa (Solanum Tuberosum, L). En los bioensayos realizados fue evaluado el comportamiento de los hidrogeles mediante el análisis de las características morfológicas de las plántulas: longitud de la parte aérea, longitud de la raíz, número de entrenudos y biomasa. Estos parámetros fueron analizados aplicando el análisis de varianza ANOVA de dos factores con múltiples muestras, en donde los factores evaluados fueron el tipo de hidrogel y el solvente usado para su síntesis. Los resultados obtenidos muestran que según el medio de cultivo estas variables se ven favorecidas por el uso de un determinado tipo de hidrogel, es decir, en el SAH los hidrogeles de PAAm son los que presentaron mejores resultados desde el punto de vista morfológico y estadístico. Para el cultivo in-vitro con solución nutritiva MS, las propiedades morfológicas de las plántulas, se vieron beneficiadas por el hidrogel de P(AAm-co-AI) sintetizado en la solución acuosa de buffer de fosfato.

Palabras clave: Hidrogeles, medios de cultivo, Poliacrilamida, Poli (acrilamida-co-ácido itacónico).

ABSTRACT

Hydrogels from poly (acrylamide) (PAAm) and of poly (acrylamide-co-itaconic acid) (P (AAm-co-AI)) synthesized in water and in an aqueous solution of phosphate buffer 0.2 M, were used as a support in the vegetable tissue culture media hydroponic autotrophic system (HAS) and in-vitro culture with Murashige-Skoog (MS) nutrient solution for the production of potato seedlings (Solanum Tuberosum, L). In the bioassays carried out, the behavior of the hydrogels was evaluated by analyzing the morphological characteristics of the seedlings: length of the aerial part, length of the root, number of internodes and biomass. These parameters were analyzed by applying the ANOVA variance analysis of two factors with multiple samples, in which the factors evaluated were the type of hydrogel and the solvent used for its synthesis. The results obtained show that, according to the culture medium, these variables are favored by the use of a certain type of hydrogel, which, in the SAH the PAAm hydrogels are the ones that presented the best results from the morphological and statistical point of view. For the in-vitro culture with MS nutrient solution, the morphological properties of the seedlings were advantageous due to the P(AAm-co-AI) hydrogel synthesized in the aqueous solution of phosphate buffer. 

Key words: Hydrogels, medium culture, Polyacrylamide, Poly(acrylamide-co-itaconic acid).
Indicadores de cambio climático en las precipitaciones
Authors: López Silva Maiquel , Carmenates Hernández Dayma , Valero Freyre Luis , López Fernández Lizmay
Published: December 2021

El presente trabajo ofrece un estudio que se desarrolló en el municipio de Ciro Redondo de la provincia Ciego de Ávila, Cuba, con el objetivo de estimar los impactos del cambio climático sobre las precipitaciones. Se analizó una serie de 40 años, en el periodo comprendido de 1978 hasta el 2017, obtenidos de forma sistemática en el pluviómetro CA 808. Se realizó la estadística descriptiva para analizar los estadígrafos fundamentales de la serie de lluvias para escala de tiempo mensual y anual. Se determinó el índice de concentración de las precipitaciones, el climograma y el criterio para evaluación de cambio climático en las precipitaciones las anomalías climáticas y el cambio del patrón de lluvias. Los días con lluvia varían entre 9 y 12 días en el mes, con tendencia a la disminución en un 20% de la serie, definiendo el periodo lluvioso y seco en un 81,64% y 18,36% de las precipitaciones del año respectivamente. El climograma identificó que los meses de junio, julio y agosto superan los 30ºC de temperatura lo que califica a la localidad como una zona  de altas temperaturas. Se valoró que existe una elevada anomalía climática negativa que ocurre en el 47,5% de los 40 años estudiados; mientras que en el patrón de desplazamiento de las precipitaciones en los últimos 5 años existen tendencias a disminuir las precipitaciones.

 

Palabras clave: precipitaciones, clima, climograma, húmedo, seco.

 

Abstract

The present work offers a study that was developed in the Ciro Redondo Municipality of the province of Ciego de Ávila, Cuba, with the objective of determining the estimation of the impacts of climate change on rainfall. A series of 40 years was analyzed, in the period from 1978 to 2017, systematically obtained in the CA 808 rain gauge. The descriptive statistics was used to analyze the fundamental statistics of the rainfall series for time scale. monthly and annual. The index of concentration of precipitations, the climogram and the criterion for evaluation of climate change in rainfall were determined by the climatic anomalies and the change of rainfall pattern. The days vary between 9 and 12 days in the month, with a tendency to decrease in 20% of the series, therefore the rainy and dry period is defined in 81.64% and 18.36% of the rainfall of the year respectively. The climogram determined that the months of June, July and August exceed the 30ºC of temperature which allow to describe the location like at high temperatures zone. It was assessed that there is a high negative climatic anomaly occurring in 47.5% out of the 40 years studied was valued; while in the pattern of rainfall displacement in the last 5 years, there is a tendency to decrease rainfall monthly.

 

Key words: rainfall, climate, climogram, wet, dry.
MACROMONÓMEROS: SÍNTESIS Y APLICACIONES
Authors: Contreras Ramírez Jesús Miguel
Published: December 2021

Los macromonómeros son ampliamente usados en la síntesis de polímeros ramificados mediante homo y/o copolimerización. Los macromonómeros se utilizan de forma muy exitosa en las polimerizaciones heterogéneas para la obtención de partículas poliméricas usadas como sistemas de liberación controlada de fármacos con alta aplicabilidad en el campo biomédico. Esta revisión presenta diferentes métodos de síntesis de macromonómeros con dobles enlaces como función polimerizable. Además, se hace referencia al uso de los macromonómeros en la obtención de polímeros que poseen arquitecturas definidas y novedosas, aunado a la evaluación del comportamiento cinético y de la reactividad que presentan estos macromonómeros. Por último, se menciona el uso de los monómeros macromoleculares en las polimerizaciones por dispersión como reactivo y como agente dispersante, los que pueden contribuir en gran medida en la fabricación de microesferas que ofrecen potenciales aplicaciones en diferentes campos de la biomedicina.

 

Palabras clave: macromonómeros, polímeros ramificados, función polimerizable, redes anfifílicas

 

Abstract

Macromonomers are widely used in the synthesis of branched polymers by homo and/or copolymerization. The macromonomers are used very successfully in heterogeneous polymerizations for obtaining polymer particles used as controlled drug release systems with high applicability in the biomedical field. This review presents different synthesis methods for macromonomers with double bonds as a polymerizable function. Besides, it is analyzed the usage of macromonomers in obtaining polymers with defined and novel architectures, besides to the evaluation of the macromonomers' kinetic behavior and reactivity presented. Finally, it is analyzed the use of macromolecular monomers in dispersion polymerizations both as a reagent and as a dispersing agent, which can contribute greatly to the manufacture of microspheres that offer potential applications in different fields of biomedicine.

 

Keywords: macromonomers, branched polymers, polymerizable function, amphiphilic networks