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Concern about responding to the needs of adult patients with bone fragility fractures has extended into risk identification and osteoporosis prevention in children and adolescents. Children with lower bone mass are thought to be at higher risk for fracture during growth and for osteoporosis later in life. The most critical period in skeletal development is that of rapid bone modeling and turnover in adolescence. Determinants of skeletal development include genetic factors; gonadal hormones; physical activity; vitamin D status; and calcium, phosphorus, and protein intake. Secondary causes of osteoporosis during childhood include corticosteroid treatment and chemotherapy. The published worldwide experience of using bisphosphonates to treat children remains limited. Dual energy x-ray absorptiometry is the gold-standard method for evaluating children's skeletal health. [ABSTRACT FROM AUTHOR]

Abstract: It is known from short-term studies that calcium supplementation influences bone accretion during growth, but whether this has any implication with regard to fracture risk reduction is unknown. To address this issue, we have, therefore, evaluated the long-term effects of calcium supplementation (calcium citrate malate 1000 mg/day) on the prevalence of fractures in a cohort of young females, participants of a 7-year clinical trial. A total of 354 females were recruited to participate in a 4-year, randomized, double-blind, placebo-controlled clinical trial covering pubertal growth spurt, with subsequent extension for 3 years into late adolescence. Participants were accustomed to dietary calcium intake of ∼830 mg/day/7 years; supplemented individuals received additional ∼670 mg of calcium per day/7 years. Participants were asked to report on the fracture history at the end of the study, followed by the subsequent verification of the fracture data. Out of 26 verified fracture cases, 9 fracture cases were documented among the calcium-supplemented individuals, and 17 fractures were confirmed among the placebo individuals. Most fractures were at the forearm (50%) and occurred around the time of menarche. The Kaplan–Meier survival analysis showed a consistently lower rate of fractures among the calcium supplemented individuals, however, this was not statistically significant. The results of this study may be important for the design of a larger intervention trial with calcium supplementation with fracture as the main outcome. The results may have the ultimate implication with regard to the prevention of bone fragility during growth. [Copyright &y& Elsevier]

BACKGROUND: Biochemical markers of bone remodeling have been extensively used (independent of bone mass measurements) to document the efficacy of various anticatabolic and anabolic bone-modifying medications in reducing fracture risk. Nonetheless, their usefulness in determining the effectiveness of osteoporosis prevention and treatment, particularly calcium supplementation, has not been well established. OBJECTIVE: This article reviews the use of biochemical markers of bone remodeling as a measure of the effect of calcium supplementation and the implications for prediction of fracture risk. METHODS: A generalized search of MEDLINE from 1966 through April 2004 using the terms osteoporosis, fracture risk, and the specific bone biomarkers of interest was conducted to identify articles relating to these biomarkers and their relationship to prediction of fracture risk. A second MEDLINE search for the same period used the terms calcium, biological markers, and fracture risk to identify studies of calcium supplementation and bone biomarkers. In both cases, the reference lists of identified review articles were searched for additional publications. RESULTS:: Several biochemical markers of bone remodeling have been shown to be positively correlated with bone mineral density and fracture risk. Furthermore, calcium supplementation has been shown to have a significant correlation with levels of a number of these biomarkers (P < 0.05): the markers of bone formation procollagen type I carboxy and amino terminal peptides and serum bone-specific alkaline phosphatase, and the markers of bone resorption urinary hydroxyproline, urinary pyridinoline, urinary deoxypyridinoline, urinary amino terminal crosslinked telopeptide, and urinary and serum carboxy terminal crosslinked telopeptide. CONCLUSIONS: Calcium supplementation has a significant effect on a number of biomarkers of bone remodeling, an effect that is, in turn, correlated with decreased fracture risk. Most studies of the efficacy of calcium supplementation in reducing bone remodeling and influencing bone mineral density and fracture risk have involved calcium carbonate, although a few studies have found that other calcium salts may produce similar results. [ABSTRACT FROM AUTHOR]

Production of non ferrous metals from secondary raw materials is far less costly than its production from primary raw materials, due to lower energy consumption. Besides, by recycling of non ferrous metals from secondary raw materials, the natural resources are saved and the amount of waste materials is reduced, directly protecting the environment. The secondary raw materials can originate in metal production and treatment, accompanied by their incorporation into the final product and its elimination due to amortization. The different methods of preparation and metallurgical treatment are used depending on secondary raw materials type. Some of them are very easy to be recycled by remelting in metallurgical furnace, while others must pass through complicated preparation before metallurgical treatment.

In 2019, 21.1 % of the EU-27 population were at risk of poverty or social exclusion. Energy poverty is one of many poverty forms and it is a widespread problem across Europe, as between 50 and 125 million people are unable to afford proper indoor thermal comfort. Energy poverty is linked to low household income, high energy costs and energy inefficient homes. These challenges are deeply connected with SDG7 and SDG1, and also produce environmental pollution. The roots of energy poverty are in polluting fuels that are the cheapest and at hand to the population in (risk of) poverty. Biomass heating is the inefficient use in old stoves and the lack of wood drying before use (the loss of up to 50% of the energy and higher energy costs of heating). Biomass and coal is also a major contributor to poor air quality in many European regions, especially in eastern part of the EU and Western Balkans. Biomass smoke contains health-damaging substances (particulate matter, PAHs etc). Studies on indoor air pollution show concentrations of PM10 may extremely exceed standards for ambient air pollution levels and put the people (mostly women and children), at increased risk of health impacts. Biomass burning also leads to the release of black carbon, which is not only a concern for health, but also as short-lived climate change forcer (SDG 13). A conservative estimate of the current contribution of biomass smoke to premature mortality in Europe amounts to at least 40,000 deaths per year. The inefficient use of the biomass means higher costs for already ‘disadvantaged’ citizens and those in risk of (energy) poverty. Energy poverty is a distinct form of poverty associated with a range of adverse consequences for people’s health and wellbeing (respiratory diseases, CVD, mental health, and stress associated with unaffordable energy bills). Poverty and energy issues as environmental and health challenges should seen through SDG 1 and SDG 7, but also through SDG 8, SDG1 1 and SD G3. [ABSTRACT FROM AUTHOR]

Evaluates the effects of gallium nitrate on bone turnover in four patients with active Paget's disease. Subjects and methods; Results; Discussion.

The effects of growth, menstrual status, and calcium supplementation on iron status were studied over 4 y in 354 girls in pubertal stage 2 who were premenarcheal at baseline (x+/-SD age: 10.8+/-0.8 y). Girls were randomly assigned to placebo or treatment with 1000 mg Ca/d as calcium citrate malate. Anthropometric characteristics, bone mass, and nutritional status were measured biannually; ferritin was measured annually; and red blood cell indexes were determined at 4 y. The simultaneous effects of iron intake and menstrual status on serum ferritin, after change in lean body mass (LBM) was controlled for, were evaluated in subjects in the upper and lower quartiles of cumulative iron intake. The average maximal accumulation of LBM (386 g/mo; 95% CI: 372, 399) occurred 0.5 y before the onset of menarche. Change in LBM was a significant predictor of serum ferritin (P < 0.0001), with a negative influence on iron status (t ratio=-4.12). The 2 fitted mathematical models representing ferritin concentrations of subjects in the upper and lower quartiles of cumulative iron intake were significantly different (P < 0.018). The regression line of the ferritin concentration in menstruating girls with high iron intakes had a less negative slope than the line fit to serum ferritin concentrations in girls with low iron intakes (NS). Serum ferritin concentrations at 0, 1, 2, 3, and 4 y were not significantly different between groups. In addition, there was no significant difference between groups in any of the red blood cell indexes. In summary, growth spurt and menstrual status had adverse effects on iron stores in adolescent girls with low iron intakes (<9 mg/d), whereas long-term supplementation with calcium (total intake: approximately 1500 mg/d) did not affect iron status. Copyright (c) 1998 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Increasing emphasis is being placed on optimizing calcium intake during growth as a way to enhance peak bone mass. Although some studies in adults have shown that high calcium intake may negatively affect magnesium utilization, few data are available regarding the interaction of calcium and magnesium in healthy children. The purpose of our study was to measure the effect of calcium intake on magnesium balance in 26 adolescent girls (mean age 11.3 y) during a 14-d period. Subjects ate a controlled basal diet containing 667 mg Ca and 176 mg Mg. In addition to the basal diet, subjects were randomly assigned in a double-blind fashion to consume 1000 mg elemental Ca/d as calcium citrate malate or a placebo. Magnesium use did not differ between the low-calcium and high-calcium groups as measured by absorption (50% compared with 55%), urinary excretion (70 compared with 74 mg/d), and fecal excretion (88 compared with 79 mg/d). Accordingly, magnesium balance was not different in subjects consuming 667 or 1667 mg Ca/d and averaged 21 mg Mg/d for the whole study group. Magnesium balance was significantly correlated with magnesium intake (r = 0.511, P = 0.008) and magnesium absorption (r = 0.723, P < 0.001). Prediction intervals from the regression of magnesium balance on intake indicated that the current recommended dietary allowance of magnesium would result in magnesium balance >/=8.5 mg/d in 95% of the girls. This value appears consistent with long-term accretion rates needed to account for the expansion of the total-body magnesium pool during growth. In summary, our observations support the adequacy of the current recommended dietary allowance for magnesium and indicate that alterations in magnesium utilization should not be anticipated in adolescent females consuming a high-calcium diet. [ABSTRACT FROM AUTHOR]

Copper mine "Cerovo"- East Serbia as well as the other ore bodies in its vicinity contain a significant amount of oxide copper minerals in their uper layers (>40%). Processing of such mixed ores by the existing concentration technologies leads to a substantial copper losses (

The experimental investigations defined both the technological scheme of the calcium production from limestone by aluminothermic process and the basic operating parameters of the particular technological phases. The limestone with high content of Mg, Na and K was used in the paper. X-ray analysis reveals that the samples contain mainly calcite with small amount of dolomite. At first, the influence of temperature, time and granulometry on the calcium carbonate calcination was examined. The dissociation process was completed in 10-15 min at 1200°C, and dissociation rate increases with decreasing of particle size up to 5 mm. Afterwards, the aluminothermic reduction process of calcium oxide was investigated. At the temperature 1200°C, and vacuum of at least 3 kPa, the reduction process completed within 2 hours. The chemical composition of calcium oxide and calcium showed increased content of magnesium oxide and alkaline oxides (especially sodium).[Projekat Ministartsva nauke Republike Srbije, br. TR34002 i br. TR34023]

In this paper the procedure of obtaining of high purity magnesium by using the vacuum distillation process has been shown. Vacuum distillation process has been conducted under low and high vacuum at different operating temperatures and times. Also, the condenser structure in vacuum equipment is set up in such a way to get the optimal conditions for obtaining of high purity magnesium. Based on experimental results, optimal process parameters were determined which justify the economy and technology of the process.

Interest for application of hydrometallurgical processes in a processing of complex sulphide ores and concentrates has increased in recent years. Their application provides better metal recoveries and reduced emission of gaseous and toxic ageneses in the environment. The kinetics and mechanism of sphalerite leaching from complex sulphide concentrate with sulphuric acid and sodium nitrate solution at standard conditions was presented in this paper. The influences of temperature and time on the leaching degree of zinc were investigated and kinetic analysis of the process was accomplished. With temperature increasing from 60 to 90°C, the zinc leaching increased from 25.23% to 71.66% after 2 hours, i.e. from 59.40% to 99.83% after 4 hours. The selected kinetic model indicated that the diffusion through the product layer was the rate-controlling step during the sphalerite leaching. The activation energy was determined to be 55 kJ/mol in the temperature range 60-90°C. XRD, light microscopy and SEM/EDX analyses of the complex concentrate and leach residue confirmed formation of elemental sulphur and diffusion-controlled leaching mechanism.

In this work, the process of the chalcopyrite leaching in sulphuric acid solution was investigated. Sodium nitrate was used as oxidant in the leaching process. Chemical reactions of leaching and their thermodynamic possibilities are predicted based on the calculated Gibbs energies and analysis of E−pH diagrams. The negative values of the Gibbs energy show that all chemical reactions are thermodynamically feasible at atmospheric pressure and in a temperature range 25-90°C. At high electrode potential and low pH values, Cu2+, Fe2+ and Fe3+ ions exist in water solutions. The increase of temperature reduces the probability of Fe3+ ion existence in the system. The chalcopyrite concentrate, enriched in the “Rudnik” flotation plant, with 27.08% Cu, 25.12% Fe, 4.15% Zn and 2.28% Pb was used in the work. XRD and DTA analysis of the concentrate reveals that the sample contains mainly the chalcopyrite with small amount of sphalerite. For the description of the reaction of leaching process the leach residuals, obtained at different conditions, were chosen for XRD, TG/DTA and SEM/EDX analyses. The elemental sulphur and chalcopyrite phases identified in leach residuals confirm our prediction that the elemental sulphur is formed during the leaching process. Accordingly, elemental sulphur is the main product of the reaction, while a minor amount of sulphide sulphur is oxidized to sulphate during the leaching. The sulphur formed during the reaction was precipitated at the particle surfaces, and slowed down the leaching rate in the final stage of leaching process. In the initial stage, the reaction rate was controlled by the surface reaction. The mechanism, latter has been changed into a diffusion controlled one.

Presents abstracts of articles adapted from the April 1998 edition of the periodical `Journal of the American College of Nutrition,' which discussed nutrition.

RNA splicing enables the functional adaptation of cells to changing contexts. Impaired splicing has been associated with diseases, including retinitis pigmentosa, but the underlying molecular mechanisms and cellular responses remain poorly understood. In this work, we report that deficiency of ubiquitin-specific protease 39 (USP39) in human cell lines, zebrafish larvae, and mice led to impaired spliceosome assembly and a cytotoxic splicing profile characterized by the use of cryptic 5' splice sites. Disruptive cryptic variants evaded messenger RNA (mRNA) surveillance pathways and were translated into misfolded proteins, which caused proteotoxic aggregates, endoplasmic reticulum (ER) stress, and, ultimately, cell death. The detrimental consequence of splicing-induced proteotoxicity could be mitigated by up-regulating the ubiquitin-proteasome system and selective autophagy. Our findings provide insight into the molecular pathogenesis of spliceosome-associated diseases.

Introduction: Current urban and transport planning practices have significant negative health, environmental, social and economic impacts in most cities. New urban development models and policies are needed to reduce these negative impacts. The Superblock model is one such innovative urban model that can significantly reduce these negative impacts through reshaping public spaces into more diverse uses such as increase in green space, infrastructure supporting social contacts and physical activity, and through prioritization of active mobility and public transport, thereby reducing air pollution, noise and urban heat island effects. This paper reviews key aspects of the Superblock model, its implementation and initial evaluations in Barcelona and the potential international uptake of the model in Europe and globally, focusing on environmental, climate, lifestyle, liveability and health aspects., Methods: We used a narrative meta-review approach and PubMed and Google scholar databases were searched using specific terms., Results: The implementation of the Super block model in Barcelona is slow, but with initial improvement in, for example, environmental, lifestyle, liveability and health indicators, although not so consistently. When applied on a large scale, the implementation of the Superblock model is not only likely to result in better environmental conditions, health and wellbeing, but can also contribute to the fight against the climate crisis. There is a need for further expansion of the program and further evaluation of its impacts and answers to related concerns, such as environmental equity and gentrification, traffic and related environmental exposure displacement. The implementation of the Superblock model gained a growing international reputation and variations of it are being planned or implemented in cities worldwide. Initial modelling exercises showed that it could be implemented in large parts of many cities., Conclusion: The Superblock model is an innovative urban model that addresses environmental, climate, liveability and health concerns in cities. Adapted versions of the Barcelona Superblock model are being implemented in cities around Europe and further implementation, monitoring and evaluation are encouraged. The Superblock model can be considered an important public health intervention that will reduce mortality and morbidity and generate cost savings for health and other sectors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)