Si System Research Articles

Alumino-Silico-thermic synthesis of high purity ferroboron alloy and its characterization

High purity ferroboron (Fe–B) alloy is used as an alloying agent for making special grades of steels, Nd-Fe-B magnets etc. In this study, alumino-silico-thermic co-reduction of Fe2O3 and B2O3 was attempted to prepare high purity Fe–B. Extensive differential thermal analysis (DTA) studies were carried out to understand the reduction behaviour of Fe2O3 and B2O3 by Al and Si. DTA exothermic peaks indicated three step reduction of Fe2O3 (Fe2O3→Fe3O4→FeO→Fe) when reacted with Al and Si separately. B2O3–Si system did not show exothermic peaks while heating indicating sluggish or no reduction, however, B2O3–Al DTA peaks indicated two step reduction behaviour. Differential thermal analysis of Fe2O3–B2O3–Al–Si indicated completion of reduction of oxides, and formation of different intermediate phases. Specially designed reduction reactors were used to produce ferroboron alloy in bulk quantities. Thermal analysis results suggested that the formation of aluminium and silicon borides could be avoided using sub-stoichiometric amount of Al and Si, which was further confirmed from the bulk thermit product. Si acted as reducing agent as well as forming low melting slag comprising of Al(Si)–B–O type oxides. Inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and Particle Induced Gamma-ray Emission (PIGE) analysis confirmed the presence of 12 wt% boron in the alloy product with lower content (<1 %) of impurity elements like Al and Si. The relationship between the chemical homogeneity with the thermit process parameters was established. Microstructure and mechanical properties confirmed the formation of Fe2B and FeB phase in the thermit alloy.

Innovations in HbA1c analysis: finding the balance between speed and accuracy. An investigation of a potential new Secondary Reference Measurement Procedure for the IFCC.

The escalating prevalence of diabetes worldwide has resulted in a dramatic increase in the number of people who need testing, which in turn necessitates faster HbA1c measurement. The Tosoh GR01 addresses the need for fast turnaround times of whilst offering pragmatic steps to maintain result accuracy in a single instrument by offering two distinct operating modes: Short Mode (SM) and Long Mode (LM). The aim of this study was to evaluate all relevant aspects of the performance of the Tosoh GR01 with a view to accepting the instrument as a future Secondary Reference Measurement Procedure (SRMP) for the IFCC. Certified Clinical & Laboratory Standards Institute (CLSI) Evaluation Protocols (EP) were used to evaluate precision (EP-5), accuracy (EP-9), linearity (EP-6), carry-over (EP-10) and the effect of hemoglobin variants and other potential interferences. Both modes demonstrated CVs <0.6 % in SI units and <0.4 % in NGSP units at 46 mmol/mol (6.4 %) and 75 mmol/mol (9.0 %) and passed both National Glycohemoglobin Standardization Program (NGSP) and International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) certification procedures when compared with 7 IFCC Certified Secondary Reference Measurement Procedures (SRMP). Sigma for both modes was >6 when using the results of EP-5 and EP-9 at an HbA1c concentration of 50 mmol/mol (6.7 %). Neither mode showed any interference with common Hb-variants except for HbAE when HbA1c was >65 mmol/mol. In the SM HbAS, HbAD and HbAC were recognized but no result was reported. There is a good balance between speed and accuracy for determining HbA1c with the Tosoh GR01 in both analytical modes and the device is suitable for use as an IFCC SRMP.

Formation of Films of Alloys of Cr–Ni, Cr–Ni–Si and Fe–Ni Systems by Sublimation and Evaporation Methods for Electronic Products

The processes of formation of films of alloys of the Cr–Ni, Cr–Ni–Si and Fe–Ni systems with a stab le elemental composition by evaporation methods are considered. It is shown that due to the large difference in the melting temperatures of Ni and Cr, nichrome films are obtained by sublimation. The design of the evaporator is proposed, which makes it possible to stabilize the composition of the films. Calculations of azeotropic compositions of alloys of the Cr–Ni–Si system have been carried out. The position of the isobars of the total pressure of iron and nickel on the state diagram was determined during evaporation in vacuum. The azeotropic composition of the alloy of the Fe–Ni system was calculated and experimentally verified.

External and Internal Loads in Sports Science: Time to Rethink?

The current paper discusses the concepts and definitions of external and internal loads in sports science and the quantification of athletes’ performance and psychobiological responses. We provide practical solutions for improving human performance assessment by suggesting related terms and consistent terminology that align with biomechanical standards. This will help to avoid discrepancies in the meaning of terms across various subdisciplines of sport and exercise science and medicine. Where possible, exercise performance should be characterized and quantified according to physical quantities such as time, distance, displacement, speed, velocity, acceleration, force, torque, work, power, and the International System of Units. These quantifications can be performed for exercises, sessions, microcycles, and mesocycles. Standardization of these terms and measurements would enable consistent communication among scientists of all knowledge areas.

Accurate Determination of Trace Water in Organic Solution by Quantitative Nuclear Magnetic Resonance.

A new method accompanied by a derived equation for accurate determination of trace water was developed by using quantitative 1H nuclear magnetic resonance (qNMR) spectroscopy. Given that the response for each chemically distinct moiety is uniformly proportional to the number of the corresponding resonant nuclei within the analyte, it is practicable to directly quantify the water content via its proton number using qNMR. In this study, three water standards with known water contents (e.g., 10.02, 1.006, and 0.103 mg/g), which were accurately determined by a well-established Coulometric Karl Fischer (CKF) titration method, were measured by using the developed qNMR method. An excellent agreement between the results from these two methods was obtained. Then, the water content of Sudan I was determined by high-field NMR (HF-NMR) spectroscopy, and the water contents of acetone and bioethanol were measured by low-field NMR (LF-NMR) spectroscopy. These results were compared with the water content measured by the CKF method to confirm the applicability of the established qNMR method. The developed method can eliminate the influences of environmental humidity and background water in the solvent; subsequently, the results calculated by the derived equation were comparable to the nominal values. Under the optimal conditions, the limit of quantitation of this method was as low as 6.7 μg. The recommended sample sizes for practical samples with various water contents (e.g., 10.02, 1.006, and 0.103 mg/g) were determined to be 5, 50, and 60 mg, respectively, which are much smaller than those required for the CKF method. The new method has a static and stable process without any side reactions, and the traceability to the SI unit can be directly achieved through the NMR internal standard. This method overcomes the limitations of the CKF method, especially for measuring methanol-insoluble substances.

Measurement of Magnesium, Zinc, and Copper in Human Serum by Using Isotope Dilution Inductively Coupled Plasma Mass Spectrometry (ID ICP-MS).

In order to evaluate the reliability of the ID ICP-MS method for the measurement of magnesium, zinc, and copper in human serum, we investigated the traceability, precision, trueness, and uncertainty of the method. This method traces the contents of magnesium, zinc, and copper in human serum to the standard materials NIST SRM3131a, SRM3168a, and SRM3114 respectively, thus completing the traceability to SI unit. The repeatability of this method for measuring magnesium, zinc, and copper in the human serum reference material GBW09152 was found to be 0.2%, 0.7%, and 0.6% (n = 9), respectively. The measurement, when employed to measure the magnesium, zinc, and copper in standard materials, had caused a maximum deviation of less than 0.88%, 1.35%, and 1.15%, respectively. The measurement results are within the stated uncertainty range of standard materials. The expanded uncertainties were 0.2 mg·kg-1, 0.04 mg·kg-1, and 0.08 mg·kg-1 (K = 2) for magnesium, zinc, and copper, respectively. Therefore, this method has high trueness, good reproducibility, and simple operation and is suitable for tracing the values of magnesium, zinc, and copper in human serum.

Traceable value of immunoglobulin G against receptor-binding domain of SARS-CoV-2 confirmation and application to point-of-care testing system development.

A highly purified and bioactive immunoglobulin G monoclonal antibody against receptor-binding domain of SARS-CoV-2 (RBD-IgG-MAb) has been accurately quantified by amino acid determination using isotope dilution liquid chromatography-mass spectrometry. Absolute quantification of RBD-IgG-MAb was achieved by averaging 4 amino acid certified reference materials, which allows the quantitative value (66.1 ± 5.8 μg/L) to be traced to SI unit (mol). Afterwards, the RBD-IgG-MAb was employed as control and calibrationcompound for the development of a point-of-care testing (POCT) system based on colloidal gold lateral flow immunoassay, which aimed to rapidly and accurately detect the level of protective RBD-IgG after vaccination. Under the detection parameters, a sigmoidal curve has been plotted between signal intensity and the logarithmic concentration for quantitative detection with the limit of detection of about 0.39μg/mL. The relative standard deviations of intra-assay and inter-assay were lower than 2.3% and 14%, and the recoveries ranged from 87 to 100%, respectively. Fingertip blood samples from 37 volunteers after vaccination were analyzed by the POCT system; results showed that levels of RBD-IgG in 33 out of 37 samples ranged from 0.45 to 2.46μg/mL with the average level of 0.91μg/mL. The developed POCT system has been successfully established with the quantity-traceability RBD-IgG-MAb as control and calibration compound, and the scientific contribution of this work can be promoted to other areas.

A-076 Abbott Alinity ci System Automated Sample Interference Indices for Immunoassays

Abstract Background The Alinity ci system Sample Interference Indices (HIL) provides a more accurate and consistent method for interpretation of interferents than time consuming visual interpretation. The Alinity c system uses specific wavelength pairs and an algorithm to provide a Sample Interference Index that can correlate with sample interference due to hemolysis, bilirubin and turbidity present in serum/plasma samples. Using just a single aspiration from a sample, the individual or all 3 indices can be selected to be reported. These values in combination with assay specific endogenous interference can be used to determine the potential for HIL interference in the Alinity i immunoassays. Methods The HIL methodology will be reviewed and discussed. The study followed Clinical and Laboratory Standards Institute (CLSI) protocol EP7-A2. Interferences were studied up to concentrations of 1000 mg/dL for hemoglobin, 30 mg/dL for bilirubin (unconjugated) and 1000 mg/dL for triglycerides in serum. Serial dilutions of the sample pools were analyzed in replicates of 4 on the Alinity c system. A cumulative summary was compiled of the Hemolysis, Icterus and Lipemia indices for 100 Alinity immunoassays. Results Using known concentrations of hemoglobin, bilirubin and Intralipid, the Abbott Semi-Quantitative Index (concentration range in mg/dL) and Qualitative Index (Blank, 1+, 2+, 3+ 4+) were confirmed on the Alinity c system. Correlation studies show a linear relationship (r = 1.0) of the indices with increasing concentration of analyte. An easy-to-use guide was created that combines the HIL Qualitative and Quantitative Index scores with the assay specific interference results to provide a guide to potential interferents for the Alinity i immunoassays. This guide provides background information on the causes of HIL interferences, conversion factors from Conventional to SI units and denotes the specific concentrations of interferents which could lead to an over or under estimation in the presence of hemoglobin, bilirubin and/or lipemia. In addition, the effects of the influence of two or more HIL interferents on assay reported results is discussed. The majority (96%) of the 100 immunoassays had no significant interference using samples with elevated H, I or L index values. The remaining 3 assays showed slight interference. Conclusion The Alinity ci system provides a simple and automated procedure for determining the sample indices (HIL) for patient specimens. These HIL values in combination with assay specific endogenous interference results can be used to determine the potential for HIL interference in the Alinity i immunoassays to avoid misdiagnosis.

The spatio-temporal diversification of SRK alleles in an Arabidopsis polyploid hybrid and introgression zone

Reproductive barriers and directional geneflow may play a key role in maintaining genetic gradients, thereby allowing ecological differentiation along ecological clines. In Brassicaceae, a sporophytic incompatibility system (SI) contributes to such barriers to geneflow, with the maternal component represented by a large diversity of SRK (stigma-specific S locus receptor kinase) alleles at varying frequencies and levels of dominance. Such clinal genetic gradient along an ecological gradient following a shift towards much drier and warmer conditions and also the bedrock type shifts from calcareous to silicious has been found earlier in an Arabidopsis introgression system involving A. lyrata and A. arenosa. The metapopulation system spans from the northeastern Austrian forealps northward towards the Danube river and the Bohemian massif. Here we explore diversification of population-level SRK gene pools across these hybrid Arabidopsis tetraploid metapopulation system and its putative parental source populations. Since it has been demonstrated that A. lyrata served as the maternal parent and A. arenosa introgressed via pollen constituting a genetic cline with decreasing contribution of A. arenosa genetic background, we test the hypothesis that this cline can be also explained by SRK allelic differentiation. A total of 603 individuals from 45 populations of introgressed and non-introgressed A. lyrata and A. arenosa across a 80 km transect were analysed for SRK allele variation. In total, 22 alleles from all four previously described dominance classes have been documented. Although there is clinal morphological and genetic variation following the introgression zone, SRK alleles do not follow this signature of the paternal taxa. Furthermore, the functional SI system is fully maintained across the transect, and crossing experiments show that there is no decrease in fitness depending on varying distances between populations along the transect studied herein. We conclude that transmission and structure of the SRK allelic gene pool contributes to the postglacial colonization success along such a pronounced ecological gradient maintaining a functional SI system and counteracting genetic depletion.

Virus-like Particles: Properties and Characteristics of Reference Materials

Virus-like particles (VLPs) have long attracted the attention of biologists and metrologists due to their dual nature. Despite their similarity to viruses, VLPs lack a virus DNA or RNA, thereby posing no threat of infection. The development of methods for the creation and standardization of VLPs, as well as for monitoring their characteristics, represents an important problem in the field of biotechnology and molecular biology. In this work, we aim to substantiate the requirements, methods, and instruments used to ensure the traceability of VLP-based certified reference materials (CRMs). The following methods for characterization of biological and physicochemical properties of such CRMs were considered: mass balance; high-performance liquid chromatography-mass spectrometry (HPLC–MS); gas chromatography-mass spectrometry (GC–MS); Karl Fischer coulometric titration; ion chromatography; inductively coupled plasma mass spectrometry; and isotope dilution. It was established that VLP-based CRMs should meet the following requirements: the presence of molecular patterns common to many pathogenic biological agents (PBAs) but absent in the organism; traceability to SI units (Systeme international d’unites, SI); the absence of own genetic material; the presence only of inactivated homogenous strains when used for vaccine delivery. VLP-based CRMs facilitate metrological support in the field of medicine and vaccine production.

What is the role of robotic surgery in ovarian cystectomy with fertility preservation?

To investigate the role of robotic single-site (RSS) ovarian cystectomy in fertility preservation, which was compared with single-port laparoscopic (SPL) surgery based on AMH changes. We retrospectively analyzed medical records of total 156 patients who underwent SPL (n = 72) or RSS (n = 84) surgery with the da Vinci® Si or Xi system. The pre/post-operative AMH levels and total diameter of ovarian cysts were measured. In addition to the surgical method, AMH changes were compared according to the laterality, multiplicity, and pathology of ovarian cysts. A comparison of the characteristics of the SPL group and RSS group, revealed that there were no significant differences in the average age, the diameter of the ovarian cyst, and the number of locule. There were also no statistical differences between the pre-operative and post-operative AMH levels and the average surgical time including the docking time in robotic surgery. A comparison based on the surgical methods, revealed that the decrease in post-operative AMH was lower in the RSS group (24.2 ± 35.9%) than in the SPL group (34.9 ± 29.1%) significantly (p = 0.044). In patients with endometriosis, the decrease in AMH was greater, than that in patients without endometriosis. A longer operation time, larger ovarian cysts and multi-locular cysts were associated with lower AMH level in both the SPL and RSS groups (Pearson correlation coefficient: – 0.320, p = 0.0001, – 0.218, p = 0.007, – 0.236, p = 0.003, respectively). RSS ovarian cystectomy could be a promising new therapeutic option for fertility preservation in complex cases to avoid an additional side port.

A Study of Evolution of Cosmological Parameters Based on a Dark Energy Model in the Framework of Brans-Dicke Gravity

The objective of the present study is to find the characteristics of evolution of a homogeneous and isotropic universe in the framework of Brans-Dicke (BD) theory of gravity. FLRW space-time, with zero spatial curvature, has been used to obtain BD field equations. Scale factor and Hubble parameter have been obtained from an ansatz for the deceleration parameter, assumed on the basis of its property of signature flip indicating a change of phase from deceleration to acceleration. Validation of the model has been achieved by a suitable parametrization of that ansatz. Expressions for energy density, pressure, equation of state (EoS) parameter, cosmological constant, gravitational constant have been derived and depicted graphically. The gravitational constant is found to decrease with time at a gradually decreasing rate. The Hubble parameter, deceleration parameter and energy density decrease with time, which is in agreement with many other studies. The value of the EoS parameter at the present epoch is negative, and it becomes more negative with time. The cosmological constant increases very rapidly in the early universe from negative to smaller negative values, becoming positive finally, with a much slower change thereafter. A cosmographic and a geometrical analysis have been carried out. It is observed that a gradual transition takes place from a regime of quintessence to phantom dark energy. An important finding of this study is that the signature flip of the deceleration parameter takes place almost simultaneously with the signature flip of the cosmological constant, implying a connection between accelerated expansion and dark energy, which is represented here by the cosmological constant. Unlike the common practice of using arbitrary units, proper SI units for all measurable quantities have been used. This theoretical investigation provides the reader with a simple method to formulate models in the framework of BD theory.

Calibration and Validation for the Surface Biology and Geology (SBG) Mission Concept: Recommendations for a Multi‐Sensor System for Imaging Spectroscopy and Thermal Imagery

AbstractThe primary objective of the National Aeronautics and Space Administration (NASA) Surface Biology and Geology (SBG) mission is to measure biological, physical, chemical, and mineralogical features of the Earth's surface, realizing a key conceptual component of the envisioned NASA Earth System Observatory (ESO). SBG is planned to launch as a two‐platform mission in the late 2020s, the first of the ESO satellites. Targeted science and applications objectives based on observations of the Earth's SBG helped to define the mission architecture and instrument capabilities for the SBG mission concept. These objectives further drove the need for enabling change detection and trending of surface biological and geological features. These needs implied fundamental calibration goals to achieve the necessary science data quality characteristics. To meet those goals, calibration and validation pre‐launch and on‐orbit methods formed a basis of the calibration and validation concept, including the combined use of on‐board references, vicarious techniques, and routine lunar imaging. International collaboration with space agencies in other countries, an important feature of the recommended SBG mission architecture, uncovered and emphasized the need for inter‐calibration techniques that underscored the importance of collaborative instrument characterization data sharing and the use of common calibration references that are International System of Units (SI) traceable in pre‐launch and post‐launch on orbit calibration mission phases. International collaboration through the use of terrestrial and aquatic networks on six continents for vicarious calibration and validation activities will further assure necessary science data quality while in orbit.

Double folding analysis of the α+28Si elastic scattering system

Using the double folding model (DFM), we reanalyzed 20 sets of experimental angular distributions for the elastic scattering [Formula: see text]+[Formula: see text]Si system in a wide energy range of [Formula: see text]-particles from 12.7[Formula: see text]MeV to 240[Formula: see text]MeV. We used three effective nucleon–nucleon (NN) interactions that are CDM3Y6, São Paulo Potential (SPP2), and Brazilian Nuclear Potential (BNP) to generate the DF potentials. The data analysis was performed using semi-microscopic (SM) and fully microscopic (FM) methods. In the SM approach, the real part of the optical potential (OP) is created with the DFM, and the Woods–Saxon (WS) potential is considered for the imaginary part of the OP. In the FM approach, the DF potential renormalization factors [Formula: see text] and [Formula: see text] for the real and imaginary parts of the OP were extracted. We investigated the energy dependencies of the [Formula: see text] and [Formula: see text] factors, as well as of nuclear potential volume integrals and reaction cross-sections. We reasonably reproduced the data using [Formula: see text] and [Formula: see text] factors obtained from their energy-dependent functions.

Measuring the Rheological and Textural Properties of Thick Purees Used to Manage Patients with Swallowing Disorders.

Texture-modified diets are the first-line compensatory strategy for older patients with swallowing and mastication disorders. However, the absence of a common protocol to assess textural properties inhibits their standardization and quality control and, thus, patient safety. This study aimed to (a) assess the rheological and textural properties of ten thick purees (Texture C, British Dietetic Association), (b) understand the effect of oral processing, and (c) measure the properties of the ready-to-swallow bolus after oral processing in healthy adults. Shear viscosity at 50 s-1 and 300 s-1 and textural properties (maximum force, cohesiveness, and adhesiveness) of boluses of ten thick purees were analyzed with a rheometer and a texture analyzer before and after oral processing (ready-to-swallow) in five healthy volunteers. Viscosity varied by 81.78% at 50 s-1 (900-4800 mPa·s) among purees before oral processing. Maximum force varied by 60% (0.47-1.2 N); cohesiveness, 18% (0.66-0.82), and adhesiveness, 32% (0.74-1.1 N·s). The high variability of viscosity was also present in ready-to-swallow boluses, 70.32% among purees. Oral processing significantly reduced viscosity in most purees (French omelet, zucchini omelet, turkey stew, red lentils, noodles, and hake fish) and also significantly reduced maximum force (7-36%) and adhesiveness (17-51%) but hardly affected cohesiveness (<5%). All thick purees met the qualitative textural descriptors for Level C texture. However, all ten purees showed significant differences in all parameters measured instrumentally and were affected differently by oral processing. This study demonstrates the need to use instrumental quality control using standardized protocols and SI units to narrow the variability and provide the optimal values for patients with dysphagia who require texture-modified diets.

Experimental investigation of phase equilibria in the Al–Ag–Si system

The phase equilibria of the Al-Ag-Si ternary system at 500 °C and 600 °C were investigated by X-ray powder diffraction (XRD) and electron probe microanalysis (EPMA). Three two-phase regions ((Al) + (Si), (Si) + Ag2Al, and (Si) + (Ag)) and two three-phase regions ((Si) + (Ag) + Ag2Al and (Si) + (Ag) + Ag2Al) were observed at 500 °C. The (Si) + Ag2Al and (Si) + (Ag) two-phase regions and (Si) + Ag2Al + liquid and (Si) + (Ag) + Ag2Al three-phase regions were identified in the isothermal section at 600 °C. A vertical section of the Al–Ag–Si system along Al0.6Si0.4–Al0.8Ag0.2 was investigated using differential scanning calorimetry (DSC) from which the temperatures of the phase-transition reactions were determined. The isothermal and vertical sections obtained in this study provide fundamental data for the thermodynamics of the Al–Ag–Si system and knowledge of the thermodynamics associated with aluminium-based alloys.

Direct joining of quartz glass and copper by nanosecond laser

In present study, quartz glass and copper, which are with a large difference of coefficient of thermal expansion by 38 times, were successfully welded without any interlayer by nanosecond (ns) laser under non-optical contact for the first time. By reasonably tuning the welding parameters, well-formed quartz glass/copper joints without any defects such as microcracks or voids can be achieved. The welded seam includes laser-unirradiated smooth region and laser-irradiated spindle melted region and both the region are composed of “Cu2O″-SiO2 system (Cu–O–Si system) and CuO. The formation of such a particular microstructure feature is attributed to the recoil pressure from ns laser ablation and the Marangoni convection at the interface. The parameters of ns laser welding including laser power, scanning velocity and the number of scans influence the laser energy input and thermal accumulation greatly during welding, thus affecting the interfacial feature and the mechanical property of the resultant joints. The shear strength of the joint can reach 33.4 MPa, which is about 80% of quartz glass shear strength. The metallurgical bonding from interfacial reaction and mechanical interlocking from physical spindle structures are the main reasons for achieving a high shear strength of the joint. We expect this study could provide a new idea for joining materials with large differences in thermophysical properties.

Antiviral Activities of Streptomyces KSF 103 Methanolic Extracts against Dengue Virus Type-2.

Dengue has long been a serious health burden to the global community, especially for those living in the tropics. Despite the availability of vaccines, effective treatment for the infection is still needed and currently remains absent. In the present study, the antiviral properties of the Streptomyces sp. KSF 103 methanolic extract (Streptomyces KSF 103 ME), which consists of a number of potential antiviral compounds, were investigated against dengue virus serotype 2 (DENV-2). The effects of this extract against DENV-2 replication were determined using the quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Findings from the study suggested that the Streptomyces KSF 103 ME showed maximum inhibitory properties toward the virus during the virus entry stage at concentrations of more than 12.5 µg/mL. Minimal antiviral activities were observed at other virus replication stages; adsorption (42% reduction at 50 µg/mL), post-adsorption (67.6% reduction at 50 µg/mL), prophylactic treatment (68.4% and 87.7% reductions at 50 µg/mL and 25 µg/mL, respectively), and direct virucidal assay (48% and 56.8% reductions at 50 µg/mL and 25 µg/mL, respectively). The Streptomyces KSF 103 ME inhibited dengue virus replication with a 50% inhibitory concentration (IC50) value of 20.3 µg/mL and an International System of Units (SI) value of 38.9. The Streptomyces KSF 103 ME showed potent antiviral properties against dengue virus (DENV) during the entry stage. Further studies will be needed to deduce the antiviral mechanisms of the Streptomyces KSF 103 ME against DENV.

An optimized enhanced-multi learner approach towards speaker identification based on single-sound segments

AbstractSpeaker Identification (SI) is the task of identifying an unknown speaker of an utterance by comparing the voice biometrics of the unknown speaker with previously stored and known speaker models. Although deep learning algorithms have been successful in different speech and speaker recognition systems, they are computationally expensive and require considerable run-time resources. This paper approaches this issue by proposing an optimized text-independent SI system based on convolutional neural networks (CNNs) that not only delivers accuracies on par with state-of-the-art benchmarks but also demands significantly fewer trainable parameters. The proposed system integrates an Enhanced Multi-Active Learner framework, which distributes the complexity of the learning task among an array of learners, with a novel SI approach in which speakers are identified based on a single sound segment of voice biometrics. Here, experiments were conducted with all 1881 VoxCeleb 1 and TIMIT speakers, and results were compared with the SI systems reported in the literature that were assessed on the same speakers’ data. Results indicate that first, the proposed system outperformed the benchmark systems’ performances by delivering up to 2.43% better top-1 accuracy, and second, it reduced the number of deep learning trainable parameters by up to 95%. The proposed SI could bring offline, large-scale speaker identification to low-end computing machines without specific deep learning hardware and make the technology more affordable.

Diamond growth in a high temperature and high pressure Fe–Ni–C–Si system: Effect of synthesis pressure

Pressure is one of the necessary conditions for diamond growth. Exploring the influence of pressure on growth changes in silicon-doped diamonds is of great value for the production of high-quality diamonds. This work reports the morphology, impurity content and crystal quality characteristics of silicon-doped diamond crystals synthesized under different pressures. Fourier transform infrared spectroscopy shows that with the increase of pressure, the nitrogen content in the C- center inside the diamond crystal decreases. X-ray photoelectron spectroscopy test results show the presence of silicon in the diamond crystals synthesized by adding silicon powder. Raman spectroscopy data shows that the increase in pressure in the Fe–Ni–C–Si system shifts the Raman peak of diamonds from 1331.18 cm−1 to 1331.25 cm−1, resulting in a decrease in internal stress in the crystal. The half-peak width decreased from 5.41 cm−1 to 5.26 cm−1, and the crystallinity of the silicon-doped diamond crystals improved, resulting in improved quality. This work provides valuable data that can provide a reference for the synthesis of high-quality silicon-doped diamonds.