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The industrial production and use of chromium have grown considerably during the past five decades. Abundances of the chromium isotopes in terrestrial samples are identical to 0.01%. Among the dominant species of chromium, the trivalent form widely occurs in nature in chromite ores which is extremely immobilized especially in water bodies. Samples were mixtures of separated chromium isotopes and the calibration was made with the same species as those used in the measurements. The method had simplified the conversion of the ores to chromyl fluoride since the element could be readily separated as lead chromate from the leaching of chromite-sodium peroxide fusions. Isotope assay of chromyl fluoride under certain conditions was measured and the measurements of chromium isotopic anomalies ratios and isotope abundance of the chromite ores have been assessed. These provided sufficient quantitative mass spectrometric data, which were analyzed to calculate the abundance and the mean atomic mass of the questioned isotopes. Based on the high mass spectroscopy stability and the correction factors, the results were of good precision (incl. negligible systematic errors normally associated to inter-laboratory discrepancies) and the Cr isotopes availability (52Cr > 53Cr > 50Cr > 54Cr) was in conjunction with other classical tools such as oxygen isotopes. This paper is important for paleoecological, environmental, archeological, forensic, and nuclear researchers.

Today’s need for renewable energy combined with modern societies' reliability on on-demand power leads us to find solutions that can store excess or produce directly to storage for later use. A MOlecular Solar Thermal (MOST) based on norbornadiene/quadricyclane(NBD/QC) does the latter with an isomeric photoswitching molecule pair. The theoretical studies of molecular solar thermals (MOST) provide a needed understanding of potential synthetic candidates. We have investigated an array of more complex solvation models for the norbornadiene/quadricycle (NBD/QC) photoswitch and the impacts of the models on the first absorption energy. Our results have been obtained with various density functional theoretical methods and basis sets.

Indigenous food processing and preservation methods are on the verge of collapse, yet they proved promising and sustainable. The study assessed the indigenous methods of shea butter processing among rural women in the Borgu Local Government Area of Niger State, Nigeria. Specifically, it described the socioeconomic characteristics of respondents, examined the shea butter processing techniques used and identified the information sources of shea butter processors in the study area. A multistage sampling technique was used to select 100 respondents. Descriptive (such as frequency count, percentage, charts and tables) and inferential statistics (such as Pearson correlation and chi-square) were used to analyze the data. Findings showed the mean age of respondents was 45.61 ± 11.82, with mean years of experience of 20.39 ± 12.96, the majority (85%) were married and the major sources of information on indigenous shea butter processing came from family members and friends. At p ≤ 0.01 there was a significant association between respondents’ usage of indigenous methods and their marital status (ᵡ2 = 84.24; p ≤ 0.01), membership in cooperative society (ᵡ2 = 40.43; p ≤ 0.01), and community membership (ᵡ2 = 53.21; p ≤ 0.01). However, there was a significant relationship between respondents’ usage of indigenous methods and household size (b = 0.290; p ≤ 0.05), quantity produced (b = 0.616; p ≤ 0.10) and annual income (b = -0.765; p ≤ 0.05). It was concluded that indigenous methods of processing shea butter are widespread among respondents; knowledge is acquired through family and friends. Among others, the study recommends that extension agents be posted to rural areas to educate rural women and build on their indigenous knowledge of processing shea butter to introduce high-quality butter.

This article refers to calculations involved with determination of ethanol, analyzed according to redox back titration principle. A quantitative reasoning, based on logical sequence of statements, is presented for derivation of the formulas required to calculate the results of chemical analyses according to stoichiometric principles. The titrations are considered as two-step analytical procedures. This way, one can gain an insight into a classical redox titration and get a knowledge on the advantages of back titrations. 

In this article, an interesting phenomenon has described the geometries and vibrational frequency of the stable AuN clusters with N = 26 to 35. We have found nine out of ten clusters are having the very same C1 symmetry, except the cluster N = 33 (D2). The finite-differentiation method has been implemented within the density-functional tight-binding (DFTB) approach. The effects of the range of interatomic forces were calculated and the desired set of system eigenfrequencies (3N-6) are obtained by diagonalization of the symmetric positive semidefinite Hessian matrix. Mainly, we have observed the vibrational spectra and the range comes in between 2.04 and 347.32 cm−1 at ground state, ∆E = 0. Most significantly, all the clusters have revealed double-state degeneracy. The vibrational spectrum is strongly dependent upon the size, shape, and structure, at the same time, the stretching and the bending mode of the atoms with respect to the bond length plays a major role. We have compared some of our results, which have an excellent agreement, with the less availability of the experimental and the theoretical predictions.

Background: Epidemiological studies report that females experience greater rates of concussion when compared with males. Biomechanical factors may result in greater post-impact head velocities and accelerations for a given force for females when compared with males. Purpose: To quantify the magnitude, frequency, duration and distribution of impacts to the head and body in rugby league match activities for females versus males. Design: Prospective descriptive epidemiological study. Methods: 21 female and 35 male amateur rugby league players wore wireless impact measuring devices (X2Biosystems; xPatch) behind their right ear over the mastoid process during match participation across a single season. All impact data were collected and downloaded for further analysis. Results: Male amateur rugby league players experienced more head impacts than female amateur rugby league players (470 ±208 vs. 184 ±18; t(12)=-3.7; p=0.0028; d=1.94) per-match over the duration of the study. Male amateur rugby league players recorded a higher median resultant Peak Linear Acceleration (PLA(g)) (15.4 vs. 14.6 g; F(824,834)=51.6; p<0.0001; t(1658)=-3.3; p=0.0012; d=0.10) but a lower median resultant Peak Rotational Acceleration (PRA(rad/s2) (2,802.3 vs. 2,886.3 rad/s2; F(831,827)=3.1; p<0.0001; t(1658)=5.7; p<0.0001; d=0.13) when compared with female amateur rugby league players Conclusion: Females recorded lower median values for PLA(g) and Head Impact Telemetry severity profile (HITSP) for all positional groups but had a higher PRA(rad/s2) for Hit-up Forwards (HUF) and Outside Backs (OSB’s) when compared with male HUF and OSB’s. Females also recorded more impacts to the side of the head (48% vs. 42%) and had a higher 95th percentile resultant PRA(rad/s2) (12,015 vs. 9,523 rad/s2) to the top of the head when compared with male rugby league players.

Plant extracts and their constituents have a long history as antifungal agents, but their use in biotechnology as preservatives, due to the increasing resistance of fungi to fungicides, has been rarely reported in Libya. The aim of this study is to evaluate the antifungal activity of ethanol extract and water extract of the wild native plant Artemisia herba-alba against two genera of mold fungi Aspergillus sp. and Rhizopus sp. This mold fungal causes significant damage to crops in the field or during storage. In this study, a hot ethanol extract was prepared using a device Soxhlet, and water extract hot as well as a cold ethanol extract and cold-water extract aqueous extract three concentrations (25% - 50% - 75%) of plant extracts were used on the tested fungi. All extracts showed an effect on the tested fungi. The concentrations of (75% - 50%) of the extracts had an effect on the tested fungi, while most concentrations of 25% of the extracts did not record any effect on the tested fungi. The hot ethanol extract of the Artemisia herba-alba plant was more effective than the other extracts. Aspergillus sp. was recorded with the highest inhibitory zone (0.73 mm).  

Background: Vitamin D deficiency in pregnancy increases several risks of breastfed mothers. To prevent these adverse events, vitamin D supplementation during pregnancy and lactation is recommended, but suggested dose ranges vary. Objective: To determine whether vitamin D3 1,800 IU/d supplementation in lactating mothers improves the vitamin D status of their breastfed infants. Materials and Methods: A randomized, placebo–controlled trial with Thai pregnant women was conducted. Lactating mothers (n=72) and their breastfed infants with insufficient maternal 25 hydroxyvitamin D (25(OH)D) levels in the third trimester were randomly assigned to two groups, one of which received 1,800 IU/d vitamin D supplementation and the other a placebo. Maternal serum 25(OH)D during lactation, cord blood, and 6-week breastfed infant serum were measured using LC-MS/MS. Results: Mean maternal age (±SD) was 27±5 years, and pre-gestational BMI was 22.29±5 kg/m2. Maternal serum 25(OH)D at baseline was 22.29±7.15 nmol/L. At 6 weeks, both maternal 25(OH)D and infant 25 (OH)D levels had increased significantly in the vitamin D supplement group of mothers and infants (68.30±15.40, 40.40±12.56 nmol/L) compared to those in placebo groups (55.15±13.57, 24.28±17.20 nmol/L) (p <0.001, p<0.001). The changes in infant 25(OH)D levels increased substantially in the vitamin D supplement group but decreased in placebo(17.49±16.27 ng/ml compared to -1.34±19.23 nmol/L in the placebo group, p<0.001). The change of maternal 25(OH)D were positively correlation to the change of 25(OH)D level in breastmilk mothers and infants by r=0.697, p<0.001 and r=0.379, p=0.003 respectively. Conclusions: Vitamin D3 supplementation to breastfed mother during lactation can increase serum 25(OH)D level in Thai breastfed mother and infants. Further work is needed to determine the optimum duration of vitamin D supplementation to normalized breastfed infants with 25(OH)D level >75 nmol/L.

Background: Hypoparathyroidism is well known to occur in thalassemia major patients, but it is thought to be uncommon and its incidence is considered to be decreasing with improvements in chelation therapy. The objective of this study was to assess the prevalence of parathyroid dysfunction in the first decade of life of the patients with thalassemia major. Patients and Methods: Ninety children with beta-thalassemia major (55 males and 35 females) with a mean age of 7.17±3.78 years (1-13 years) and age and sex matched control group of 60 healthy children (36 males and 24 females) with a mean age 6.98±3.66 years (1-13) years. Serum parathyroid hormone (PTH), serum total Calcium (Ca), serum phosphorus (P), serum alkaline phosphatase (ALP), serum 25-hydroxyvitamin D (25-OHD) and serum ferritin levels were measured. Result: PTH levels were higher than normal range in 23 (25.6%) patients with a mean value of 75.2±31.3 µg/mL compared to those having normal range level (35.3±15.2 µg/mL). Ca levels were found low in 11 patients (12.2%), and P levels were found high in 2 (2.22%) and low in 4 (4.44%) patients while high ALP levels were found in 6 (6.67%) patients. 25-OHD levels were low in all patients with a mean value of 24.95±5.82. Conclusion: Reports in the literature indicate that parathyroid dysfunction due to iron overload generally occurs in 2nd or 3rd decade of patients with thalassemia major. However, our study shows that PTH due to iron overload may develop in a significant number of thalassemia major patients, therefore, all thalassemics should be carefully watched for endocrine organ function such as hyperparathyroidism might occur even in the first decade of the patients with thalassemia major.

Nutrition is the process of supplying the organism with substances that have certain useful characteristics for the organism. It is through the process of nutrition that the organism receives the necessary amount of energy required for normal life activity. The cell is a structural and functional unit of the human body, and it is from a set of similar formations that tissue, organ, and organ systems are formed. Consequently, each cell of the body must receive the necessary supply of nutrients in order to continue its normal functioning. Cellular nutrition is the ability of each cell of the human body to consume nutrient molecules in the amount they need. In this case, the object of the study is just that nutrition, which begins with the nourishment of an individual cell. This article presents the results obtained by analyzing the data regarding the process of making the cell's consumption of the right nutrients while taking into account how the transition to cellular nutrition affects the environment and its constituents.