122 research outputs found

    SCHOOL PROBLEMS IN THE EDUCATION AND DEVELOPMENT OF GIFTED CHILDREN: PSYCHOLOGICAL ASPECT

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    Purpose of the Study: The urgency of the problem under investigation is due to the fact that the issue of gifted students’ education is one of the most difficult and interesting aspects of contemporary pedagogy. The purpose of the article is to identify the psychological characteristics of the gifted students’ development. In this article, the school difficulties of gifted students are revealed and the causes of internal and external nature are analyzed. The authors pay special attention to the social and emotional consequences, which can be rather destructive if appropriate assistance is not provided by teachers, psychologists, and parents. Methodology: The leading approach to the study of this problem is a method of theoretical analysis and synthesis of social, political and psycho-pedagogical literature. Results: The main result of the study is a theoretical analysis of the relationship between learning and the development of gifted children and their psychological characteristics. Application: The materials of the article can be useful for teachers, students and a wide range of readers interested in the problems of gifted students’ education

    SCHOOL PROBLEMS IN THE EDUCATION AND DEVELOPMENT OF GIFTED CHILDREN: PSYCHOLOGICAL ASPECT

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    Purpose of the Study: The urgency of the problem under investigation is because, the issue of gifted students’ education is one of the most difficult and interesting aspects of contemporary pedagogy. The purpose of the article is to identify the psychological characteristics of the gifted students’ development. In this article, the school difficulties of gifted students are revealed and the causes of internal and external nature are analyzed. Methodology: The leading approach to the study of this problem is a method of a theoretical analysis and synthesis of social, political, and psycho-pedagogical literature. Results: The main result of the study is a theoretical analysis of the relationship between learning and the development of gifted children and their psychological characteristics. Application:The materials of the article can be useful for teachers, students, and a wide range of readers interested in the problems of gifted students’ education. The authors pay special attention to the social and emotional consequences, which can be rather destructive if appropriate assistance is not provided by teachers, psychologists, and parents

    Bone mineral health is sensitively related to environmental cadmium exposure- experimental and human data

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    Exposure to cadmium (Cd) is recognised as one of the risk factors for osteoporosis, although critical exposure levels and exact mechanisms are still unknown. Here, we first confirmed that in male Wistar rats challenged orally with 6 different levels of Cd (0.3–10 mg/kg b.w.), over 28 days, there was a direct dose relationship to bone Cd concentration. Moreover, bone mineral content was significantly diminished by ∼15% (p < 0.0001) plateauing already at the lowest exposure level. For the other essential bone elements zinc (Zn) loss was most marked. Having established the sensitive metrics (measures of Cd exposure), we then applied them to 20 randomly selected human femoral head bone samples from 16 independent subjects. Bone Cd concentration was inversely proportional to trabecular bone mineral density and mineral (calcium) content and Zn content of bone, but not the donor's age. Our findings, through direct bone analyses, support the emerging epidemiological view that bone health, adjudged by mineral density, is extremely sensitive to even background levels of environmental Cd. Importantly, however, our data also suggest that Cd may play an even greater role in compromised bone health than prior indirect estimates of exposure could reveal. Environmental Cd may be a substantially determining factor in osteoporosis and large cohort studies with direct bone analyses are now merited

    Nickel’s Role in Pancreatic Ductal Adenocarcinoma: Potential Involvement of microRNAs

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    Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancer types with a limited overall survival rate due to the asymptomatic progression of symptoms in metastatic stages of the malignancy and the lack of an early reliable diagnostic biomarker. MicroRNAs (miRs/miRNAs) are small (~18–24 nucleotides), endogenous, non-coding RNAs, which are closely linked to the development of numerous malignancies comprising PDAC. Recent studies have described the role of environmental pollutants such as nickel (Ni) in PDAC, but the mechanisms of Ni-mediated toxicity in cancer are still not completely understood. Specifically, Ni has been found to alter the expression and function of miRs in several malignancies, leading to changes in target gene expression. In this study, we found that levels of Ni were significantly higher in cancerous tissue, thus implicating Ni in pancreatic carcinogenesis. Hence, in vitro studies followed by using both normal and pancreatic tumor cell lines and increasing Ni concentration increased lethality. Comparing LC50 values, Ni-acetate groups demonstrated lower values needed than in NiCl2 groups, suggesting greater Ni-acetate. Panc-10.05 cell line appeared the most sensitive to Ni compounds. Exposure to Ni-acetate resulted in an increased phospho-AKT, and decreased FOXO1 expression in Panc-10.05 cells, while NiCl2 also increased PTEN expression in Panc-10.05 cells. Specifically, following NiCl2 exposure to PDAC cells, the expression levels of miR-221 and miR-155 were significantly upregulated, while the expression levels of miR-126 were significantly decreased. Hence, our study has suggested pilot insights to indicate that the environmental pollutant Ni plays an important role in the progression of PDAC by promoting an association between miRs and Ni exposure during PDAC pathogenesis

    Quantized Densely Connected U-Nets for Efficient Landmark Localization

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    In this paper, we propose quantized densely connected U-Nets for efficient visual landmark localization. The idea is that features of the same semantic meanings are globally reused across the stacked U-Nets. This dense connectivity largely improves the information flow, yielding improved localization accuracy. However, a vanilla dense design would suffer from critical efficiency issue in both training and testing. To solve this problem, we first propose order-K dense connectivity to trim off long-distance shortcuts; then, we use a memory-efficient implementation to significantly boost the training efficiency and investigate an iterative refinement that may slice the model size in half. Finally, to reduce the memory consumption and high precision operations both in training and testing, we further quantize weights, inputs, and gradients of our localization network to low bit-width numbers. We validate our approach in two tasks: human pose estimation and face alignment. The results show that our approach achieves state-of-the-art localization accuracy, but using ~70% fewer parameters, ~98% less model size and saving ~75% training memory compared with other benchmark localizers. The code is available at https://github.com/zhiqiangdon/CU-Net.Comment: ECCV201

    Double-loop hysteresis of multisite dilute Sr(Y1x_{1-x}Dyx_x)2_2O4_4 single crystal Kramers paramagnets: electron-phonon interaction, quantum tunneling and cross-relaxation

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    Experimental and theoretical studies of the dynamic magnetization in swept magnetic fields of the orthorhombic SrY2_2O4_4 single-crystals doped with the Dy3+^{3+} Kramers ions (0.01 and 0.5 at.%) with natural abundances of even and odd Dy isotopes are presented. Impurity ions substitute for Y3+^{3+} ions at two nonequivalent crystallographic sites with the same local CsC_s symmetry but strongly different crystal fields. Well pronounced double-loop hysteresis is observed at temperatures 2, 4, 5 and 6 K for sweeping rates of 5 and 1 mT/s. The microscopic model of spectral, magnetic and kinetic properties of Dy3+^{3+} ions is developed based on the results of EPR, site selective optical spectra and magnetic relaxation measurements. The derived approach to the dynamic magnetization in the sweeping field based on the numerical solution of generalized master equations with time-dependent transition probabilities induced by the electron-phonon interaction, quantum tunneling and cross-relaxation allowed us to reproduce successfully the evolution of the hysteresis loop shape with temperature, sweeping rate and concentration of paramagnetic ions.Comment: 11 pages, 6 figures, 2 tables, 52 reference

    Bilijarna funkcija u radnika profesionalno izloženih aluminijskoj prašini i dimu

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    This study investigated billiary secretory function in workers occupationally exposed to aluminium dust and fumes. It included a group of 34 male workers aged (44.1±7.8) years and exposed up to 4.6 mg m-3 of aluminium dust and fumes in workplace air for (21.6±2.5) years, and a group of 30 unexposed control male workers. Serum and urine aluminium levels were measured in both groups before and after chelating treatment with 1 g deferoxamine by intramuscular injection. Billiary function was assessed by measuring gamma-glutamyl transpeptidase, alkaline phosphatase, 5-nucleotidase, cholesterol and its fractions, total and indirect bilirubin, and bile acids. We then analysed the relationship between Al exposure and billiary function. In the exposed group mean serum aluminium was significantly higher [(4.91±3.86) µg L-1] than in controls. The same was true for urine Al before [(1.57±1.93) µg L-1] and after deferoxamine [(11.51±14.97) µg L-1]. Total and indirect bilirubin and alkaline phosphatase were significantly higher in the exposed than in control workers, and they correlated with urine Al after the chelating treatment. Our findings suggest that chronic occupational exposure to aluminium dust and fumes leads to a significant body retention of aluminium. The impaired biliary secretion in the exposed workers manifested itself in subclinical signs of cholestasis.Eksperimentalna istraživanja na životinjama pokazuju da kronična izloženost aluminiju može izazvati smanjen prijenos organskih aniona preko žučnih kanalića, što ima za posljedicu poremećaje sekrecije žuči i kolestazu. Učinci kronične izloženosti aluminiju na bilijarnu funkciju u ljudi do sada nisu istraživani. Procjenjivali smo učinke na bilijarnu funkciju radnika koji su profesionalno izloženi prašini i dimu aluminija. U izloženoj skupini bila su 34 muškarca, životne dobi (44,1±7,8) godina koji su tijekom (21,6±2,5) godina bili izloženi razini do 4,6 mg m-3 prašine i dima aluminija. Kontrolna skupina sastojala se od 30 neizloženih radnika. Vrijednosti aluminija određene su u serumu i mokraći u obje skupine prije i nakon davanja kelatirajućeg spoja (deferoksamin u dozi od 1 g im.). Za procjenu bilijarne funkcije rabljeni su ovi pokazatelji: γ-glutamil transpeptidaza, alkalna fosfataza, 5-nukleozidaza, kolesterol, ukupni i indirektni bilirubin te žučne kiseline. Analizirana je korelacija između izloženosti aluminiju i bilijarne funkcije. Srednja vrijednost Al u serumu izloženih radnika [(4,91±3,86) µg L-1], kao i koncentracije Al u mokraći prije [(1,57±1,93) µg L-1] i nakon primjene kelatirajućeg spoja [(11,5±15,0) µg L-1] bile su statistički značajno više u odnosu na vrijednosti u kontrolnih ispitanika. Vrijednosti ukupnog i indirektnoog bilirubina te alkalne fosfataze bile su statistički značajno više u izloženih radnika i pozitivno su korelirale s ukupnim Al izlučenim mokraćom nakon primjene kelatora. Može se zaključiti da kronična profesionalna izloženost prašini i dimu aluminija dovodi do tjelesnog opterećenja aluminijem i poremećaja bilijarne funkcije, što se odražava supkliničkim znakovima kolestaze

    GC–MS and GC–NPD Determination of Formaldehyde Dimethylhydrazone in Water Using SPME

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    Formaldehyde dimethylhydrazone (FADMH) is one of the important transformation products of residual rocket fuel 1,1-dimethylhydrazine (1,1-DMH). Thus, recent studies show that FADMH toxicity is comparable to that of undecomposed 1,1-DMH. In this study, a new method for quantification of FADMH in water based on solid phase microextraction (SPME) in combination with gas chromatography (GC) with mass spectrometric (MS) and nitrogen-phosphorus detection (NPD) is presented. Effects of SPME fiber coating type, extraction and desorption temperatures, extraction time, and pH on analyte recovery were studied. The optimized method used 65 micron polydimethylsiloxane/divinylbenzene fiber coating for 1 min headspace extractions at 30 °C. Preferred pH and desorption temperature from the SPME fiber are >8.5 and 200 °C, respectively. Detection limits were estimated to be 1.5 and 0.5 μg L−1 for MS and NPD, respectively. The method was applied to laboratory-scale experiments to quantify FADMH. Results indicate applicability for in situ sampling and analysis and possible first-time detection of free FADMH in water

    Lipidna peroksidacija i aktivnost antioksidativnih enzima u eritrocitima radnika profesionalno izloženih aluminiju

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    Current research indicates that lipid peroxidation could have a role in aluminium toxicity. The aim of this study was to asses lipid peroxidation and antioxidative enzyme activity in erythrocytes of workers occupationally exposed to aluminium. We investigated a group of 59 workers (Al group) exposed to aluminium fumes (contamination factor F=8.07 to 13.47, national maximal allowed concentration value is 2 mg m-3). The control group (C group) consisted of 75 subjects employed in lime production who had not been occupationally exposed to aluminium or any known toxic substance. Erythrocyte aluminium concentrations were significantly higher in the exposed group than controls [Al group (8.41±3.66) µg L-1, C group (5.60±0.86) µg L-1, p<0.001]. In the Al group, erythrocyte malondialdehyde concentration was also significantly higher [Al group (189.59±81.27) µmol L-1, C group (105.21±49.62) µmol L-1, p<0.001] and antioxidative enzyme activity reduced for glucoso-6-phosphatedehydrogenase [Al group (5.05±1.70) IU g-1 Hb, C group (12.53±4.12) IU g-1 Hb, p<0.001], glutathione reductase [Al group (1.41±0.56) IU g-1 Hb, C group (1.89±0.57) IU g-1 Hb, p<0.001], glutathione peroxidase [Al group (12.37±5.76) IU g-1 Hb, C group (15.54±4.85) IU g-1 Hb, p<0.001], catalase [Al group (116.76±26.60) IU g-1 Hb, C group (158.81±71.85) IU g-1 Hb, p<0.001] and superoxide dismutase [Al group (1175.8±149.9) IU mg-1 Hb, C group (1377.9±207.5) IU mg-1 Hb, p<0.001].Rezultati suvremenih istraživanja pokazuju da lipidna peroksidacija može imati važnu ulogu u toksičnosti aluminija. Cilj istraživanja bio je da se ispita lipidna peroksidacija i aktivnost antioksidativnih enzima u eritrocitima kod radnika profesionalno izloženih aluminiju. Ispitivanjem je obuhvaćena skupina od 59 radnika (Al skupina) profesionalno izloženih aluminiju (faktor onečišćenja F=8,07 do 13,47, nacionalna maksimalno dopuštena koncentracija je 2 mg m-3). Kontrolna skupina sastojala se od 75 osoba zaposlenih u proizvodnji vapna koje nikada nisu bile profesionalno izložene aluminiju ni drugim toksičnim tvarima. U skupini izloženoj aluminiju utvrđene su statistički signifikantno više koncentracije aluminija u eritrocitima nego u kontrolnoj skupini [Al skupina (8,41±3,66) µg L-1, kontrolna skupina (5,60±0,86) µg L-1, p<0,001]. U Al skupini utvrđene su statistički značajno više koncentracije malondialdehida u eritrocitima [Al skupina (189,59±81,27) µmol L-1, kontrolna skupina (105,21±49,62) µmol L-1, p<0,001]. Također, u Al skupini utvrđene su i statistički značajno niže aktivnosti antioksidativnih enzima u eritrocitima: glukozo- 6-fosfatdehidrogenaza [Al skupina (5,05±1,70) IU g-1 Hb, kontrolna skupina (12,53±4,12) IU g-1 Hb, p<0,001], glutationreduktaza [Al skupina (1,41±0,56) IU g-1 Hb, kontrolna skupina (1,89±0,57) IU g-1 Hb, p<0,001], glutationperoksidaza [Al skupina (12,37±5,76) IU g-1 Hb, kontrolna skupina (15,54±4,85) IU g-1 Hb, p<0,001], katalaza [Al skupina (116,76±26,60) IU g-1 Hb, kontrolna skupina (158,81±71,85) IU g-1 Hb, p<0,001] i superoksiddizmutaza [Al skupina (1175,8±149,9) IU mg-1 Hb, kontrolna skupina (1377,9±207,5) IU mg-1 Hb, p<0,001]
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