A Summary of Satellite Orbit Related Calculations

The configuration of satellite network systems is based on the quantities and properties related to the satellite orbit. It is extremely important to carefully define parameters and equations describing the orbit path correctly to make the whole configuration correct. Three different coordinate systems are in use to define satellite orbit: the Latitude-Longitude-Altitude coordinate system, the Right Ascension-Declination coordinate system and the Azimuth-Elevation coordinate system. These coordinate systems are equivalent with respect to the position of the satellite of interest and can easily be converted one to another. One of these coordinate systems would be used depending on the nature of the problem to be solved. Based upon these coordinate systems, the position of a satellite, the visibility of a satellite and antenna direction from a ground station, and a footprint radius of a satellite, etc. can be calculated.<P

High prevalence of an alpha variant lineage with a premature stop codon in ORF7a in Iraq, winter 2020–2021

Publisher Copyright: Copyright: © 2022 Al-Rashedi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Since the first reported case of coronavirus disease 2019 (COVID-19) in China, SARS-CoV-2 has been spreading worldwide. Genomic surveillance of SARS-CoV-2 has had a critical role in tracking the emergence, introduction, and spread of new variants, which may affect transmissibility, pathogenicity, and escape from infection or vaccine-induced immunity. As anticipated, the rapid increase in COVID-19 infections in Iraq in February 2021 is due to the introduction of variants of concern during the second wave of the COVID-19 pandemic. To understand the molecular epidemiology of SARS-CoV-2 during the second wave in Iraq (2021), we sequenced 76 complete SARS-CoV-2 genomes using NGS technology and identified genomic mutations and proportions of circulating variants among these. Also, we performed an in silico study to predict the effect of the truncation of NS7a protein (ORF7a) on its function. We detected nine different lineages of SARS-CoV-2. The B.1.1.7 lineage was predominant (80.20%) from February to May 2021, while only one B.1.351 strain was detected. Interestingly, the phylogenetic analysis showed that multiple strains of the B.1.1.7 lineage clustered closely with those from European countries. A notable frequency (43.33%) of stop codon mutation (NS7a Q62stop) was detected among the B.1.1.7 lineage sequences. In silico analysis of NS7a with Q62stop found that this stop codon had no considerable effect on the function of NS7a. This work provides molecular epidemiological insights into the spread variants of SARS-CoV-2 in Iraq, which are most likely imported from Europe.Peer reviewe

Distributed Decoding of Cyclic Block Codes Using a Generalization of Majority-Logic Decoding

One-step majority-logic decoding is one of the simplest algorithms for decoding cyclic block codes. However, it is an effective decoding scheme for very few codes. This paper presents a generalization based on the "common-symbol decoding problem." Suppose one is given M (possibly different) codes over the same field; suppose further that the codewords share a single symbol in common. The common-symbol decoding problem is that of estimating the symbol in the common position. (This is equivalent to one-step majority logic decoding when each of the "constituent" codes is a simple parity check.) This paper formulates conditions under which this decoding is possible and presents a simple algorithm that accomplishes the same. When applied to decoding cyclic block codes, this technique yields a decoder structure ideal for parallel implementation. Furthermore, this approach frequently results in a decoder capable of correcting more errors than one-step majority-logic decoding. To demonstrate the simplicity of the resulting decoders, an example is presented

Mortalidade infantil por causas no Estado de São Paulo (Brasil) em 1983: análise sob a perspectiva das causas múltiplas de morte Infant mortality by causes in the State of S.Paulo (Brazil) in 1983: analysis under the perspective of multiple causes of death

Objetivou-se apresentar a mortalidade infantil por causas no Estado de São Paulo, Brasil, com base nos dados de 1983 obtidos a partir da classificação por causas múltiplas de morte, disponíveis desde a implantação do Sistema de Classificação Automática de Causas de Morte. Detectaram-se dois tipos de casos bem definidos: os óbitos ocorridos predominantemente no período neonatal, e cujo processo mórbido envolve quase que exclusivamente as afecções pertencentes ao Capítulo das Perinatais da Classificação Internacional de Doenças; e os óbitos ocorridos principalmente no período pós-neonatal, em cujo processo mórbido aparecem mencionadas significativamente as infecções intestinais, a septicemia, a desnutrição, a desidratação e a broncopneumonia. O estudo da associação entre as principais causas de morte mostrou, por um lado, a imaturidade e a prematuridade fortemente relacionadas com as afecções respiratórias do recém-nascido e com as infecções específicas do período perinatal; e por outro lado, um complexo inter-relacionamento entre as outras cinco causas mencionadas.<br>An analysis of child mortality by causes was made on the basis of classification by multiple causes of death. For this archives containing records of child deaths in the State of S.Paulo (Brazil) for 1983 were used. The underlying cause and the associated causes, according to various clustering types, were, among other variables, retrieved from each record. Two types of cases with clearly determined characteristics were detected: those occurring predominantly during the neonatal period with the morbid process involving almost exclusively diseases in the Perinatal chapter (Chapter XV of the International Classification of Diseases, 9th Revision), and those occurring after the neonatal period with their morbid process showing a significant presence of intestinal infections, septicemia, malnutrition, dehydration and bronchopneumonia. An analysis of M/B ratios, between the number of mentions of each cause and the number recorded as the underlying cause, shows the importance of the study by multiple causes of death in order to avoid the underestimation of the incidence of some diseases that represent more frequently a terminal phase of the morbid process, and are thus mentioned mainly as associated causes. The study of the association of the main causes of death, using a measure of association called "Yule's Q", revealed that the respiratory diseases of the newborn as well as the specific infections of the perinatal period are intimately linked to immaturity and prematurity. It revealed, at the same time, the existence of a complex interrelationship between the 5 most frequent causes in the post-neonatal period, since one of them always occurs significantly associated with at least one of the others in the same group

Novel Indole-Pyrazine Alkaloid: Synthesis, Characterization, and Crystal Structure

A heterocyclic molecule of a novel class with a multiple ring system has been synthesized using a new and simple strategy and acetic acid as catalyst. The structure of the title molecule has been determined by spectral analysis and single crystal X-ray diffraction analysis. The compound crystallizes in monoclinic system, space group P21/c, with two crystallographically independent molecules in an asymmetric unit. The two molecules show close comparable geometric parameters and a similar conformation of fused-ring systems. The crystal structure is stabilized by a combination of N–H⋅⋅⋅O and C–H⋅⋅⋅O hydrogen bonds, where independent molecules display equivalent interaction patterns

High prevalence of an alpha variant lineage with a premature stop codon in ORF7a in Iraq, winter 2020–2021

Publisher Copyright: Copyright: © 2022 Al-Rashedi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Since the first reported case of coronavirus disease 2019 (COVID-19) in China, SARS-CoV-2 has been spreading worldwide. Genomic surveillance of SARS-CoV-2 has had a critical role in tracking the emergence, introduction, and spread of new variants, which may affect transmissibility, pathogenicity, and escape from infection or vaccine-induced immunity. As anticipated, the rapid increase in COVID-19 infections in Iraq in February 2021 is due to the introduction of variants of concern during the second wave of the COVID-19 pandemic. To understand the molecular epidemiology of SARS-CoV-2 during the second wave in Iraq (2021), we sequenced 76 complete SARS-CoV-2 genomes using NGS technology and identified genomic mutations and proportions of circulating variants among these. Also, we performed an in silico study to predict the effect of the truncation of NS7a protein (ORF7a) on its function. We detected nine different lineages of SARS-CoV-2. The B.1.1.7 lineage was predominant (80.20%) from February to May 2021, while only one B.1.351 strain was detected. Interestingly, the phylogenetic analysis showed that multiple strains of the B.1.1.7 lineage clustered closely with those from European countries. A notable frequency (43.33%) of stop codon mutation (NS7a Q62stop) was detected among the B.1.1.7 lineage sequences. In silico analysis of NS7a with Q62stop found that this stop codon had no considerable effect on the function of NS7a. This work provides molecular epidemiological insights into the spread variants of SARS-CoV-2 in Iraq, which are most likely imported from Europe.Peer reviewe

Happiness among dentists: a multi-scale, multi-national study from 21 countries

Objectives: The extent to which dentists are happy with their profession and their life has not been well studied. The present study aimed to explore the level of happiness, satisfaction with life and psychological well-being among a sample of dental professionals from 21 countries. Materials and Methods: The sample comprised 2,200 dentists from 21 countries. Three scales – Subjective Happiness Scale (SHS), Satisfaction With Life Scale (SWLS), and Affect Balance Scale (ABS) – were used to measure the subjective responses. Data related to demographic and social characteristics were recorded. Mann–Whitney and Kruskal–Wallis tests were used as appropriate. Scales were correlated, and multiple linear regression analyses were employed to identify the independent determinants of SHS, SWLS and ABS. Data were analysed using the SPSS software program; a value of P lt 0.05 was considered significant. Results: The overall mean scores of SHS, SWLS and ABS were 18.53 ± 5.06, 23.06 ± 6.25 and 1.26 ± 2.40, respectively, with significant differences found across countries: dentists working in Croatia, Peru and Serbia recorded the highest scores, unlike dentists practicing in Yemen, Syria, and Iraq, who recorded the lowest scores. There were significant, moderately positive correlations between the various scales: SHS and SWLS: r = 0.535, P  lt  0.001; SHS and ABS: r = 0.58, P  lt  0.001; and SWLS and ABS: r = 0.533, P  lt  0.001. Country of practice, age, qualification and monthly income were the significant independent predictors of SHS, SWLS and ABS. Conclusion: Country of residence and social characteristics were associated with dentists’ responses regarding their feelings and subjective well-being