Miracle-dz/UniFAR-FTUs huggingface dataset:
A new formulation for above-the-MUF loss

When existing HF ionospheric propagation predictions are compared with measurements, the monthly median signal strength is found to be in error by more than 20 dB in an appreciable number of cases. Probably the main reason for such large discrepancies is the unrealism of any existing treatment of above-the-MUF (maximum usable frequency) loss. A programme of measurements of HF signal and noise intensities on path lengths of 120-2300 km, primarily directed to the study of fading statistics, is providing information relevant to the determination of above-the-MUF loss, because constraints on the frequencies which could be transmitted resulted in the operating frequency equalling and exceeding the basic MUF on a significant number of occasions. The experimental data and the theory support the hypothesis that the main physical mechanism involved in above-the-MUF propagation is ground side-scatter, rather than ionospheric forward-scatter. >
Internal and external factors contributing to variability in consonant accuracy of Arabic–French simultaneous bilingual children

Abstract This study aims to describe the relationships between child-internal and child-external factors and the consonant accuracy of bilingual children. More specifically, the study looks at internal factors: expressive and receptive vocabulary, and external factors: language exposure and language status, of a group of 4-year-old bilingual Arabic–French children. We measured the consonant accuracy of the children by the percentage of correct consonants in a Picture-Naming Task and a Non-Word Repetition Task in each language. The results suggest a significant relationship between vocabulary and consonant accuracy. A cross-language correlation was observed between the expressive vocabulary level of the majority language (French) and the consonant accuracy of the minority language (Arabic). Also, a significant correlation was found between Arabic language exposure and Arabic consonant accuracy. Finally, consonant accuracy was significantly higher in French tasks than in Arabic, despite the individual differences of the children.
Co-Existence of Free-Living Amoebae and Potential Human Pathogenic Bacteria Isolated from Rural Household Water Storage Containers

Simple Summary In many households in rural communities, water needed for drinking and cooking is fetched from rivers, fountains, or boreholes shared by the community. The water is then stored in various storage containers for several days without treatment and exposed to several conditions that could potentially contaminate the water and cause diseases. If the storage containers are not regularly and properly cleaned, biofilms can form inside the containers. Several microorganisms can be found inside the biofilm that can potentially cause diseases in humans. One such group of organisms is called free-living amoebae, which graze on the bacteria found inside the biofilm. Several of these potentially harmful bacteria have adapted and can survive inside these free-living amoebae and potentially cause diseases when ingested by humans. Abstract This study investigated the co-existence of potential human pathogenic bacteria and free-living amoebae in samples collected from stored water in rural households in South Africa using borehole water as a primary water source. Over a period of 5 months, a total of 398 stored water and 392 biofilm samples were collected and assessed. Free-living amoebae were identified microscopically in 92.0% of the water samples and 89.8% of the biofilm samples. A further molecular identification using 18S rRNA sequencing identified Vermamoeba vermiformis, Entamoeba spp. , Stenamoeba spp. , Flamella spp. , and Acanthamoeba spp. including Acanthamoeba genotype T4, which is known to be potentially harmful to humans. Targeted potential pathogenic bacteria were isolated from the water samples using standard culture methods and identified using 16S rRNA sequencing. Mycobacterium spp. , Pseudomonas spp. , Enterobacter spp. , and other emerging opportunistic pathogens such as Stenotrophomonas maltophilia were identified. The results showed the importance of further studies to assess the health risk of free-living amoebae and potential human pathogenic bacteria to people living in rural communities who have no other option than to store water in their homes due to water shortages.
Inducing single-mode oscillation in FabryߝPerot InGaAsP lasers by applying external optical feedback

The authors report on inducing single-mode oscillation in InGaAsP multimode lasers with Fabry-Perot (FP) structures by applying external optical feedback (OFB). The study is based on numerical solution of a time-delay multimode rate equation model taking into account both symmetric gain suppression and asymmetric gain suppression (AGS) of modal gain. The mode dynamics and modal operation are characterised over a wide range of OFB in terms of time trajectories of the most dominant modes and the corresponding time-average output spectrum. The obtained results show that strong OFB reduces AGS relative to the linear gain in the vicinity of the dominant modes. This effect moderates the contribution of AGS to the longitudinal mode competition in such a way to induce oscillation in single mode with the laser operating in continuous wave. In this region of strong OFB, the side-mode suppression ratio increases with strengthening OFB. Increasing the external cavity length was found to decrease the OFB range of single-mode oscillation and enhances chaotic dynamics of the laser.
The role of oxidant status on the etiopathogenesis of unexplained infertility and intracytoplasmic sperm injection – embryo transfer success: a case-control study

Abstract The present study aims to evaluate the role of follicular fluid (FF) and serum (s) total oxidant status (TOS), total antioxidant status (TAS) and oxidative stress index (OSI) on the etiopathogenesis of unexplained infertility (UI) and intracytoplasmic sperm injection-embryo transfer (ICSI-ET) success. Twenty UI patients and 20 controls with male factor undergoing an ICSI-ET cycle were recruited. FF samples aspirated from mature follicles and blood samples collected just before the oocyte retrieval were stored until analysis. Embriyo quality and implantation, clinical pregnancy and living birth rates were evaluated. FF-TOS and FF-OSI of the UI patients were higher than the control group. s-TOS and s-OSI were significantly increased in the UI group compared to the control group. However, only s-TOS was positively associated with UI diagnosis after age-adjustment. FF-OSI was negatively associated with embryo quality in the UI group (but not in the whole group) after age-adjustment. No significant effect of TAS, TOS, and OSI on implantation, clinical pregnancy and live birth rate was observed. In conclusion, especially s-TOS can have a partial role in the etiopathogenesis of UI. High FF-OSI can decrease the quality of embryo in patients with UI. Impact statement What is already known? Total oxidant status (TOS), total antioxidant status (TAS), and oxidative stress index (OSI), which is the ratio of TOS to TAS, provide a broad overview of redox status. What do the results of this study add? An elevated serum TOS (s-TOS) was associated with UI after age-adjustment. Follicular fluid OSI (FF-OSI) was negatively associated with embryo quality and embryo score in the UI group (but not in the whole group) after age-adjustment. No significant effect of TAS, TOS, and OSI was observed on implantation, clinical pregnancy, and live birth rate. What are the implications of these findings for clinical practice and/or further research? Evaluation of FF-OSI in women with unexplained infertility can be considered to predict embryo quality. Further studies that evaluate antioxidant agents to decrease oxidative stress in UI and its’ clinical implications are warranted.
Probabilistic risk assessment and water quality index of a tropical delta river

Water plays a major role in supporting the wellness and life processes in living things as well as in the ecological structure’s stabilities. However, several environmental scientists have recounted the alarming menace unfit water quality portends as well as the shortfalls of its global utilization in various spheres of life. This study aims to determine the fitness of the Ossiomo River and its likely health risk impact when consumed or used for other domestic purposes. The outcome of the physicochemical and heavy metal characterization showed that most of the parameters surpassed the slated benchmarks. Findings from the study revealed a significant difference (p < 0.05) for water temperature, color, TDS, BOD5, HCO3, Na, Fe, Mn, and THC across the four stations respectively. Meanwhile, pH, salinity, turbidity, TSS, DO, Cl, P, NH4H, NO2, NO3, SO4, Zn, Cu, Cr, Ni, Pb, and V showed no significant (p > 0.05) across the four stations respectively. The pH level of the water was slightly acidic at the range of 4.40–6.82. The outcome of the computed water quality index showed that station 1 (66.38) was poor for human ingestion which was above the set slated benchmarks of 26–50. However, stations 2–4 (163.79, 161.79, and 129.95) were unsuitable for drinking which was above the set slated benchmarks of 100. The outcome of the health risk evaluation revealed that the hazard quotients (HQs) were considered greater than 1 (>1) for Cr (2.55). The hazard index (0.46) via the dermal pathway was <1 while the ingestion (4.35) pathway was >1. The sum of the HQs (4.81) was also > 1. Thus, there are possible non-carcinogenic health risks via direct ingestion of the water. The outcome from the carcinogenic risk for Pb, Cr, and Cd (6 × 10–3, 4.00 × 10–1, and 1.22 × 100), was somewhat greater than the target goal (1.0 × 10–6 to 1.0 × 10–4) of carcinogenic risks stipulated by the United States Environmental Protection Agency for drinking water, respectively, especially for Cd. There might be a potential carcinogenic risk if the water is consumed when the metal contents are higher than the target limits set. Sustainable farming and treatment of wastes from industrial outputs should be the main management of this watercourse.
Drug Induced Liver Injury: Perspective of the Adverse Drug Reaction Reports to the Portuguese Pharmacovigilance System from 2010 to 2019

Background: Drug induced liver injury (DILI) is an adverse drug reaction that causes liver damage in a predictable (dose-dependent) or an unpredictable (idiosyncratic) fashion. We performed an assessment of DILI in Portugal, by analyzing the reports, sent to the Portuguese Pharmacovigilance System (PPS). Methods: A search was performed on the PPS database, in a 10-year time frame, from 1 January 2010 to 31 December 2019. Results: There was not a prevalence of either sex in any age group. Most reports (n = 1120, 55.0%) belonged to patients in the age group 19–64 years old. Hepatitis (n = 626, 26.7%) was the most common adverse drug reaction in our study. Hepatotoxicity (n = 362, 15.5%) and hepatitis (n = 333, 14.2%) were more frequent in age group 19–64 years old. Cholestasis was more prevalent in adults independently of age. Hepatic fibrosis and encephalopathy were more common in the elderly. Most patients consumed between one and four suspected drugs (n = 1867, 92%). Most patients in our study evolved to “cure” (n = 796; 39%). Hepatotoxicity (n = 23; 13.8%) and hepatitis (n = 610; 25.9%) had a female predominancy while choluria (n = 8; 4.8%) and splenomegaly (n = 8; 4.8%) were of male predominance. Conclusions: DILI is rare but can be fatal. As such, an active search of DILI is necessary.
Crowd control: Reducing individual estimation bias by sharing biased social information

Cognitive biases are widespread in humans and animals alike, and can sometimes be reinforced by social interactions. One prime bias in judgment and decision-making is the human tendency to underestimate large quantities. Previous research on social influence in estimation tasks has generally focused on the impact of single estimates on individual and collective accuracy, showing that randomly sharing estimates does not reduce the underestimation bias. Here, we test a method of social information sharing that exploits the known relationship between the true value and the level of underestimation, and study if it can counteract the underestimation bias. We performed estimation experiments in which participants had to estimate a series of quantities twice, before and after receiving estimates from one or several group members. Our purpose was threefold: to study (i) whether restructuring the sharing of social information can reduce the underestimation bias, (ii) how the number of estimates received affects the sensitivity to social influence and estimation accuracy, and (iii) the mechanisms underlying the integration of multiple estimates. Our restructuring of social interactions successfully countered the underestimation bias. Moreover, we find that sharing more than one estimate also reduces the underestimation bias. Underlying our results are a human tendency to herd, to trust larger estimates than one’s own more than smaller estimates, and to follow disparate social information less. Using a computational modeling approach, we demonstrate that these effects are indeed key to explain the experimental results. Overall, our results show that existing knowledge on biases can be used to dampen their negative effects and boost judgment accuracy, paving the way for combating other cognitive biases threatening collective systems.
Differences in Attitudes Toward Catalog Retailers of Apparel Among Social/Economic Risk Orientation Groups

This research examined whether perceived social/economic risk related to apparel products influenced attitudes about attributes of apparel catalog retailers, overall attitude toward apparel catalog retailers, and actual purchase of apparel from catalogs. Self administered questionnaires were mailed to a random sample of catalog shoppers resulting in 458 respondents. Data were collected on levels of economic and social risks perceived for purchasing apparel, the importance of various apparel shopping needs and wants, and the belief that catalog retailers possessed attributes that met apparel shopping needs and wants. Results revealed that level of social/ economic risk did influence attitudes toward catalog attributes of economic utility, home environment, merchandise assortment, catalog clientele, and interaction with catalog personnel. Levels of socialleconomic risk also influenced annual apparel expenditures from catalogs but did not affect overall attitude toward catalog retailers and number of annual apparel purchases from catalogs.
Resonant link bidirectional power converter. II. Application to bidirectional AC motor drive without electrolytic capacitor

This paper proposes a new power converter which consists of two identical 3-phase PWM modulators and a novel resonant circuit. A new control strategy is integrated to realize the bidirectional power converter without an electrolytic link capacitor. The power flow between converters is bidirectional and the regenerative braking is inherent. The source side currents maintain sinusoidal waveforms with a unity power factor. It is observed in the experiment that by balancing the active power between the source and load side, the voltage across a small ceramic link capacitor can be maintained within a small deviation from the reference. Simulation results and experimental results are presented to verify the operational principles. >
Model-Based Optimization of a Serial Resonant DC-DC Power Converter

The paper presents a model-based optimization of a serial resonant DC-DC converter. The essence of this method for the optimal design of power electronic devices is on the basis of simple dependences to determine the initial values of the circuit elements, and subsequently by applying optimization procedures to obtain their final values. This avoids the use of more precise but at the same time more complex design procedures and methodologies. The use of this approach is justified from the point of view of the fact that the tolerances of the building blocks of power electronic devices are in a fairly wide range - 20÷30%. In this way, it becomes a natural combination, complement, and development of classical design methods with innovative, based on the application of techniques of modern computational mathematics and modeling.
A novel space-voltage vector modulated sinewave three-phase inverter with high-frequency transformer-coupled resonant DC link

A novel type of quasi-resonant DC link (QRDCL) three-phase voltage-sourced inverter circuit topology operating under a commutation principle of the auxiliary high-frequency (HF) transformer-assisted zero voltage switching (ZVS)-PWM is presented. The basic operating principle of this power conversion circuit using auxiliary transformer-assisted QRDCL (TQRDCL) more suitable for CVCF/UPS, power active filter, switched-mode PWM converter, and new energy-interfaced power supplies for utility-interactive interconnection, is presented in this paper. Its operating characteristics are discussed and evaluated in terms of using the computer-aided simulation results. The experimental inverter circuit is tested and examined for CVCF/UPS systems on the basis of the hard switched PWM inverter. This tested equipment is discussed for linear and nonlinear electrical loads under the conditions of large load variations and voltage fluctuations from a practical point of view. <<ETX>>
Reduction of audible switching noise in induction motor drives using random position space vector PWM

Random pulse width modulation (RPWM) is a switching technique used to spread voltage and current harmonics over a wide frequency range. By using a randomly changing inverter switching frequency, the power spectrum of the electromagnetic acoustic noise can be spread to the wideband area. Wideband noise is much more comfortable and less annoying than narrowband noise. Thus, RPWM has been attracting interest as an excellent method for the reduction of acoustic noise in inverter drive systems. A new RPPWM (random position space vector PWM) is proposed and implemented. Each of three phase pulses is located randomly in each switching interval. Along with randomisation of the PWM pulses, space vector modulation is also executed in a C167 microcontroller. Simulation and experimental results show that the voltage and current harmonics are spread to the wideband area and that the audible switching noise is reduced by using the proposed RPPWM method.
Errors in Analyses for Capacity and Timing Design of Signalized Intersections in Absence of Steady Queue Discharge Rates

Many models for the analysis of capacity and signal timing of signalized intersections are based on the assumption that queue discharge will quickly reach a steady maximum rate after the green interval begins. This assumption leads to a common practice of using saturation flow and lost time as parameters in modeling the requirements for lane capacity, intersection performance, and signal timing. However, recent field data indicate that the queue discharge rate may continue to increase long after green onset. For this type of queue discharge characteristic, the traditional applications of lost time and saturation flow may result in significant errors when lane capacity and modeling optimal cycle length are estimated. The extent of such errors is assessed on the basis of the queue discharge characteristics observed in 38 urban traffic lanes.
A Combined Optimization‐Assimilation Framework to Enhance the Predictive Skill of Community Land Model

Land Surface Model (LSM) predictions are affected by unknown parameters, uncertain meteorological forcings, inaccurate initial conditions, and incomplete process representation. While parameter optimization (PO) algorithms have been used to estimate the model parameter for best model performance, the use of data assimilation (DA) has been receiving increased prominence to characterize the uncertainties in such models. However, it is still an open question that how DA techniques can be used together with PO algorithms to enhance the performance of LSMs for different applications. In this study, a combined framework composed of the PO algorithm—Adaptive Surrogate Modeling Based Optimization (ASMO) and the DA algorithm—Evolutionary Particle Filter with Markov Chain Monte Carlo (EPFM), is used to improve the soil moisture (SM) estimates of Community Land Model (CLM) across the Tibetan Plateau in China. The SM data from the Soil Moisture Active Passive satellite are used as the benchmark data for model improvement. To demonstrate the usefulness and effectiveness of the proposed approach, the simulated SM values are validated against the SM observations collected from the in situ networks in the Tibetan Plateau, China. The findings revealed that the joint application of ASMO and EPFM algorithms results in more accurate and reliable SM estimates of CLM compared to when they are solely employed. This study suggests that the combined optimization‐assimilation framework can be utilized for improving the predictive skill of the other large‐scale complex LSMs while accounting for the uncertainties associated with both model parameters and state variables.
Topological Ring Currents and Bond Currents in Neutral and Dianionic Altans and Iterated Altans of Benzene, Naphthalene, and Azulene.

In previous studies, the Hückel-London-Pople-McWeeny (HLPM) method was used to calculate the "topological" ring currents and bond currents that are associated with the mono-altans, and the doubly and triply iterated altans, of corannulene and coronene and their respective dianions. This gave rise to some intriguing patterns in these currents, which were partially rationalized by a detailed examination of the lone nonbonding orbitals that each of these structures possesses. In the present work, the same HLPM approach is used to investigate whether analogous changes in bond-current patterns are observed when going from the neutral species to the dianions of the iterated altans derived from some other, simpler, "parents" having molecular graphs with a nullity of zero. The altans and iterated altans of three of the simplest parents are studied: the neutral species (altan)n-benzene, (altan)n-naphthalene, and (altan)n-azulene, with n = 1, 2, and 3, together with their corresponding dianions. Analogous bond-current patterns are indeed encountered, some of which are likewise rationalized by a detailed consideration of the nonbonding orbitals.
A Two Input Two Output Step Up Type Transformerless DC-DC Converter

A transformerless two input two output step up DC-DC converter is introduced in this paper. The main features of the presented converter are good efficiency, simultaneous power delivery from the connected energy sources, relatively lower voltage stress across the switching devices, unidirectional power flow etc. The given converter is constructive in the hybrid energy system as it incorporates two sources and supplies two different voltages at the load side. Various working states are explained with the help of supporting equations and equivalent circuits. The output voltage equations are deduced. Converter justification has been done by the help of experimental and simulation results. Different waveforms like voltages and currents of inductor, output voltages etc., obtained from both the experimental and simulation studies are included to underline the skillful function of the converter.