20 research outputs found

    On the Selection of Samples in Probability Proportional to Size Sampling: Cumulative Relative Frequency Method

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    Generally in the sense that, the unit with large size contain more ancillary information than the unit with smaller size. So when samples from different sized subgroups or units are used and sampling is taken with the same probability, the chances of selecting a member from a large group are less than selecting a member from a smaller group although here the chances of selecting a member from a large group will be greater than selecting a member from a smaller group. That is it is clear that, the probability of selecting a unit is positively proportional to its size. The aim of this paper is to propose a method of selecting samples in probability proportional to size. This method uses relative frequency to select samples in probability proportional to size. Comparatively it takes less time and easy to apply than Cumulative Total Method and Lahiri’s Method.   Keywords: Probability Proportional to Size (PPS) Sampling, Cumulative Total Method, Lahiri’s Method, Cumulative Relative Frequency Method.

    A New (Proposed) Formula for Interpolation and Comparison with Existing Formula of Interpolation

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    The word “interpolation” originates from the Latin verb interpolare, a contraction of “inter,” meaning “between,” and “polare,” meaning “to polish.” That is to say, to smooth in between given pieces of information. A number of different methods have been developed to construct useful interpolation formulas for evenly and unevenly spaced points. The aim of this paper is to develop a central difference interpolation formula which is derived from Gauss’s Backward Formula and another formula in which we retreat the subscripts in Gauss’s Forward Formula by one unit and replacing by . Also, we make the comparisons of the developed interpolation formula with the existing interpolation formulas based on differences. Results show that the new formula is very efficient and posses good accuracy for evaluating functional values between given data. Keywords: Interpolation, Central Difference, Gauss’s Formula

    Role of GSH and Iron-Sulfur Glutaredoxins in Iron Metabolism—Review

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    Glutathione (GSH) was initially identified and characterized for its redox properties and later for its contributions to detoxification reactions. Over the past decade, however, the essential contributions of glutathione to cellular iron metabolism have come more and more into focus. GSH is indispensable in mitochondrial iron-sulfur (FeS) cluster biosynthesis, primarily by co-ligating FeS clusters as a cofactor of the CGFS-type (class II) glutaredoxins (Grxs). GSH is required for the export of the yet to be defined FeS precursor from the mitochondria to the cytosol. In the cytosol, it is an essential cofactor, again of the multi-domain CGFS-type Grxs, master players in cellular iron and FeS trafficking. In this review, we summarize the recent advances and progress in this field. The most urgent open questions are discussed, such as the role of GSH in the export of FeS precursors from mitochondria, the physiological roles of the CGFS-type Grx interactions with BolA-like proteins and the cluster transfer between Grxs and recipient proteins

    Performance evaluation of a cabinet solar dryer for drying red pepper in Bangladesh

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    A cabinet type solar dryer was designed and fabricated over a collector and dryer area of 4.00 m2 and 7.5 m2 respectively for the geographical condition of Bangladesh. Red pepper was used to test the performance of the dryer. The upper tray and lower tray pepper drying needed 36 and 41 h to reduce moisture from 73% (wet basis) to 10% (wet basis) respectively and found 9 kg dried pepper from 30 kg fresh red ripe pepper. In contrast, open sun drying needed 85 h to reduce moisture from 73% (wet basis) to 11% (wet basis) and produced 2.43 kg dried pepper from 8 kg red ripe pepper. The average global radiation was about 133 W/m2 while the flux incidence and flux absorbed on collector was about 128 W/m2 and 103 W/m2 respectively. The average collector and dryer efficiency was about 48% and 34% respectively. The average exergy efficiency was obtained 63%. The average rate of top, bottom and side collector loss was 37 W/m2, 20 W/m2 and 3 W/m2 respectively. The upper tray, lower tray and open sun pepper seed germination was 76%, 81% and 85% respectively (P≥0.01). The redness value of lower tray pepper (a*=27.1) was higher followed by upper tray (a*=24.7) and open sun pepper powder (a*=21.1), which means direct exposure of sunlight diminishes the quality of pepper colour. The redness value of fabricated solar drying was significantly (P≤0.01) higher than that of open sun drying

    The target specificity of thioredoxin family proteins is determined by electrostatic compatibility

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    The thioredoxin (Trx) family of proteins comprises many key enzymes in redox signaling, that catalyzes specific reversible redox reactions, e.g. dithiol-disulfide exchange reactions, (de-)glutathionylation, trans-nitrosylation, or peroxide reduction. With the analysis of a large number of proteins, as well as a certain redox couple in [article 1] and [article 4], we demonstrated that electrostatic complementarity is the major distinguishing feature that controls the specific interactions of Trxs with their target proteins. The primary aim of this work was to determine the importance of this specific interaction and the prediction, modulation, and engineering of functional redox interactions of Trx family proteins. To understand the role of electrostatic complementarity for the mammalian Trx1-TrxR complex, we generated more than 20 hTrx1 mutants and systematically engineered the electrostatic potential within and outside the contact area with TrxR [article 1]. The effects of these specific alterations distributed all over the protein surface were analyzed by enzyme kinetics, differential scanning fluorimetry (DSF), circular dichroism (CD) spectroscopy, and MD simulations. Trx family proteins have a broad and very distinct substrate specificity, which is a prerequisite for redox switching. In [article 4], we comprehensively compared the classification of various redoxins from all kingdoms of life based on their similarity in amino acid sequence, tertiary structure, and electrostatic properties. These similarities were then correlated to the existence of common interaction partners. Our analyses confirmed that the primary and tertiary structure similarities do not correlate to the target specificity of the proteins as thiol-disulfide oxidoreductases. However, we demonstrated that the electrostatic properties of the protein from both Trx or Grx subfamilies is the major determinant for their target specificity. Although structurally very similar, CxxC/S-type or class I Grxs act as oxidoreductases and CGFS-type or class II Grxs act as FeS cluster transferases. In [article 3], we re-investigated the structural differences between the two main classes of Grxs to solve the mystery of the missing FeS transferase activity of the CxxC/S-type and the lack of oxidoreductase activity of the CGFS-type Grxs. The presence of a distinct loop structure adjacent to the active site is the major determinant of the Grx function. We confirmed that the function of Grxs can be switched from oxidoreductase to FeS cluster transferase by construction of a CxxC/S-type Grx with a CGFS-type Grx loop and vice versa. Results of several in vitro and in vivo assays together with the detailed structural analyses indicate that not a radically different substrate specificity accounts for the lack of activity, but rather slightly different modes of GSH binding, which is an essential nucleophile required in redox and iron homeostasis. Various processes within the cell depend on GSH, including redox reactions, reversible posttranslational modifications, and iron metabolim. GSH is not only important in the export of FeS precursors from mitochondria, but it is also an essential cofactor for cluster binding in iron sulfur Grxs. In [article 2], we discussed the role of GSH and iron sulfur Grxs in iron metabolism, the physiological role of CGFS-type Grx interactions with BolA- like proteins, and the cluster transfer between Grxs and recipient proteins. The first well characterized physiological function of a Grx-BolA hetero complex is presented with the Grx3/4-Fra2-mediated regulation of iron homeostasis in yeast. In synopsis, the results presented and discussed in these articles and the manuscript support the concept of electrostatic properties as the main determinant in substrate specificity towards functional predictions in Trx family proteins. The mathematical model presented here showed significantly accuracy and precision in function prediction. We are aware that our findings are focused on Trx family proteins as a particular family of proteins, but by using a machine learning strategy this mathematical model is being trained with numerous different protein models for better efficacy and accuracy, that may lead to new insights also in the specific interactions of other protein families. The new concept for the substrate specificity determinant doesn’t eliminate previously described aspects for molecular recognition, instead it reveals a deeper understanding of the protein-protein interaction. The 3D structural elements of a protein play a significant role in the specificity and function. We have been able to activate an inactive protein by replacing defined structural elements. Elimination of the loop structure from CGFS-type Grx5 transformed it from an FeS transferase into an oxidoreductase and the activity was further increased by modification of the active site. We believe that the present findings may be useful to investigate proteins in great detail regarding their function based on structure and electrostatic properties. Understanding the nature of the specific interactions may enable us to specifically modify the signal transduction pathways

    Forecasting the Sugarcane Production in Bangladesh by ARIMA Model

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    Around 70% of the world’s sugar is produced from sugarcane. The production of sugarcane is fluctuated from year to year due to fluctuation of area under sugarcane cultivation. According to FAO, sugar requirement per capita/day is 29g and Bangladesh requires 1.0-1.2 million tonnes of sugar/year to meet the demand of domestic consumption. To meet the demand of domestic consumption of sugar, it is too much essential to estimate the production of sugar since sugar is produced mainly from sugarcane in Bangladesh which leads us to do this research. The main purpose of this research is to identify the Auto-Regressive Integrated Moving Average (ARIMA) model that could be used to forecast the production of sugarcane in Bangladesh. This study considered the published secondary data of yearly sugarcane production in Bangladesh over the period 1971 to 2013. The best selected Box-Jenkins ARIMA model for forecasting the sugarcane productions in Bangladesh is ARIMA (0,2,1). The comparison between the original series and forecasted series shows the same manner indicating fitted model are statistically well behaved to forecast sugarcane productions in Bangladesh i.e., the models forecast well during and beyond the estimation period to a satisfactory level

    Forecasting of Wheat Production in Kushtia District & Bangladesh by ARIMA Model: An Application of Box-Jenkin’s Method

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    After independence, in 1971, Bangladesh faced an acute food shortage. Production of rice, the main crop, declined because of the disruption of virtually all agricultural activities during the War of Liberation, and also due to various natural calamities, such as floods, droughts, cyclones, and rapid population growth. It was realized that rice alone could not meet the food requirement of the country. Wheat was therefore chosen as an alternate food crop in the winter season, which remains mostly free from natural calamities. Trend of wheat consumption is increasing over the three decades due to rapid expansion of green revolution technologies, irrigation in dry season, government subsidies in agriculture, improved seeds, increase of arable land, appropriate pesticides use and sufficient fertilizer use. One of the main aims of the Millennium Development Goals (MDG) of Bangladesh by the year 2015 is to eradicate hunger, chronic food insecurity, and extreme destitution. Thus it is essential to estimate the production of food-grains. The main purpose of this paper is to identify the Auto-Regressive Integrated Moving Average (ARIMA) model by Box-Jenkin’s methods that could be used to forecast the production of wheat in Kushtia district as well as Bangladesh. The best selected ARIMA model for forecasting the wheat productions in Kushtia district is ARIMA (1,2,1), and, for whole Bangladesh it is ARIMA (0,2,1). This paper makes a comparison between the original series and forecasted series which also shows the same trend in wheat productions, indicating the fitted model are statistically well behaved to forecast wheat productions in Kushtia district as well as Bangladesh

    A Non-Linear Biostatistical Graphical Modeling of Preventive Actions and Healthcare Factors in Controlling COVID-19 Pandemic

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    Background: With the insurgence of the COVID-19 pandemic, many people died in the past several months, and the situation is ongoing with increasing health, social, and economic panic and vulnerability. As most of the countries relying on different preventive actions to control the outcomes of COVID-19, it is necessary to boost the knowledge about the effectiveness of such actions so that the policymakers take their country-based appropriate actions. This study generates evidence of taking the most impactful actions to combat COVID-19. Objective: In order to generate community-based scientific evidence, this study analyzed the outcome of COVID-19 in response to different control measures, healthcare facilities, life expectancy, and prevalent diseases. Methods: It used more than a hundred countries’ data collected from different databases. We performed a comparative graphical analysis with non-linear correlation estimation using R. Results: The reduction of COVID-19 cases is strongly correlated with the earliness of preventive initiation. The apathy of taking nationwide immediate precaution measures has been identified as one of the critical reasons to make the circumstances worse. There is significant non-linear relationship between COVID-19 case fatality and number of physicians (NCC = 0.22; p-value ≤ 0.001), nurses and midwives (NCC = 0.17; p-value ≤ 0.001), hospital beds (NCC = 0.20; p-value ≤ 0.001), life expectancy of both sexes (NCC = 0.22; p-value ≤ 0.001), life expectancy of female (NCC = 0.27; p-value ≤ 0.001), and life expectancy of male (NCC = 0.19; p-value ≤ 0.001). COVID-19 deaths were found to be reduced with increased medical personnel and hospital beds. Interestingly, no association between the comorbidities and severity of COVID-19 was found excluding asthma, cancer, Alzheimer’s, and smoking. Conclusions: Enhancing healthcare facilities and early imposing the control measures could be valuable to prevent the COVID-19 pandemic. No association between COVID-19 and other comorbidities warranted further investigation at the pathobiological level

    Prevalence and determinants of wife-beating in Bangladesh: evidence from a nationwide survey

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    Background Intimate partner violence (IPV) is a global public health concern, with women in low- and middle-income countries (LMICs) bearing a disproportionately high burden. This study investigates the prevalence and factors correlated with attitudes regarding wife-beating among Bangladeshi women in urban–rural contexts. Methods A sample of 13,033 urban women and 51,344 rural women data from the Bangladesh Multiple Indicator Cluster Survey (MICS) 2019 were analyzed using the Chi-square test and ordinal logistic regression model. Results The findings reveal that arguing with her husband is the widespread reason for wife-beating in Bangladesh (urban: 17.3%, rural: 21.9%), followed by neglecting the children (urban: 12.7%, rural: 15.8%). About 8% of urban women and 10% of rural women favoured the opinion that refusing to involve sexual intercourse is a legitimate justification for wife-beating. In comparison, around 5% feel that a husband has a right to beat his wife due to burning food. The respondents’ age, education, marital status, number of children, socioeconomic level, any health or physical difficulty, having problems becoming pregnant, and the husband’s age are all significant factors in justifying wife-beating. Conclusions Bangladesh has a massive challenge in eliminating IPV. Women from lower socioeconomic classes, low levels of education, other challenges, and residents of rural areas are particularly more vulnerable than their urban counterparts. Therefore, it is vital to develop a proper action plan that considers women’s education and occupation to raise awareness of the various implications of wife-beating in women, particularly in Bangladesh’s rural areas
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