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The effects of both Li modification and cooling rate on the microstructure and tensile properties of an in-situ prepared Al-15 pct Mg2Si composite were investigated. Adding 0.3 pct Li reduced the average size of Mg2Si primary particles from ~30 to ~6 μm. The effect of cooling rate was investigated by the use of a mold with different section thicknesses from 3 to 9 mm. The results show a refinement of primary particle size as a result of both Li additions and cooling rate increases, and their effects are additive. Similarly, both effects increased ultimate tensile stress (UTS) and elongation values. The thin sections show somewhat unexpectedly low and scattered tensile results attributed to the casting defects observed in fracture surfaces. The Li-modified alloy displays serrated yielding behavior that is not fully explained here. The refinement by Li and enhanced cooling rate is explained in terms of an analogy with the effect of Sr and cooling rate in Al-Si alloys, and is ultimately attributed to the effect of the alkali and alkaline earth metals deactivating oxide double films (bifilms) suspended in Al melts as favored substrates for intermetallics. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To determine the prevalence of permanent and transient congenital hypothyroidism (CH) in Isfahan, Iran. METHODS: In 256 primarily diagnosed CH patients identified through the neonatal screening programme from May 2002 to February 2005, treatment was discontinued for 4 weeks and T4 and thyroid stimulating hormone (TSH) were measured. Permanent or transient CH was determined from the results of the thyroid function tests and the radiologic findings. Patients with TSH levels >6 (mIU/l) were diagnosed with permanent CH. RESULTS: Results were available from 204 patients, of whom 122 patients were diagnosed with permanent CH (59.8%) (prevalence 1:748 births), and 82 with transient hypothyroidism (prevalence 1:1114). Permanent CH was associated with higher initial TSH levels than transient hypothyroidism (P < 0.05). The most common aetiology of CH was dyshormonogenesis. CONCLUSION: The rates of both permanent and transient CH in our study were higher than the comparable worldwide rates. The transient group had low T4 levels, suggesting that iodine contamination should be investigated. The aetiology of CH was also different from that recorded in many other studies. [ABSTRACT FROM AUTHOR]

Abstract: The effects of both Li modification and cooling rate on the microstructure and tensile properties of an in situ prepared Al–15%Mg2Si composite were investigated. It was found that the addition of 0.3%Li reduces the average size of Mg2Si primary particles from ∼30 to ∼6μm. The effect of cooling rate was investigated by the use of a mold with different section test bars. The results showed an increase in both UTS and elongation values with reduction in section thicknesses corresponding to increasing cooling rates. Adding Li also raised the tensile strength and elongation values and reduced the number of decohered particles observed in fracture surfaces thereby increasing the alloy''s ductility. Data scatter and unexpected low tensile values of 3mm sections were attributed to casting defects observed in fracture surfaces. Large clusters of Mg2Si particles and eutectic cell boundaries were found to be potential crack propagation paths in this alloy. [Copyright &y& Elsevier]

Analisis metode dan isi terhadap sebuah kamus perlu dilakukan dengan tujuan untuk mengetahui sejauh mana aturan ilmiah penulisan kamus digunakan di dalamnya, serta dalam bidang apa kamus tersebut bisa digunakan. Dalam hal ini, kamus Idris al-Marbawi, secara metode dan isi termasuk kamus yang bisa dikatakan memenuhi standard. Dari aspek metode, yang menyangkut pendahuluan kamus di mana masuk di dalamnya sejarah bahasa yang terkandung di dalamnya, tujuan penulisan kamus dan data kamus, serta aspek desainnya yang meliputi struktur mikro, struktur makro, penjelasan dan ilustrasi makna, jumlah makna, singkatan, kode dan tanda baca, kamus Idris al-Marbawi tergolong lengkap. Hanya satu saja dari semua bagian tersebut yang terlewatkan, yaitu sejarah bahasa dalam arti aturan dan struktur bahasa Arab tidak diuraikan di dalamnya. Adapun dilihat dari aspek isi yang meliputi kelengkapannya, fokus isinya, obyektifitas isinya, dan penjelasan dalam pemaparan isinya, kamus Idris al-Marbawi juga memenuhi semuanya. Dengan demikian, kamus ini bisa dinilai sebagai kamus yang masih layak dipakai, meskipun dengan beberapa kekurangannya. Kekurangan tersebut misalnya, penggunaan bahasa Arab Melayu yang bagi sebagian orang tidak mudah untuk dipahami, digunakannya akar kata sebagai awal pencarian makna kata sementara tidak ada penjelasan awal tentang teori dasar pembentukan kata tersebut.

We show that chemistry can be used to trigger a nanofaceting transition. In particular, the segregation of Ag to an asymmetric tilt grain boundary in Cu is investigated. Aberration-corrected electron microscopy reveals that annealing the bicrystal results in the formation of nanometer-sized facets composed of preferentially Ag-segregated symmetric Σ5{210} segments and Ag-depleted {230}/{100} asymmetric segments. Our observations oppose an anticipated trend to form coarse facets. Atomistic simulations confirm the nanofacet formation observed in the experiment and demonstrate a concurrent grain boundary phase transition induced by the anisotropic segregation of Ag.

Background: Considering the higher prevalence of congenital hypothyroidism (CH) in Iran and the importance of determination of the etiology of CH for assessing appropriate treatment strategies, understanding the pathogenesis of CH and the implications of its inheritance and prognosis, the aim of this study was to determine the etiology of CH 7 years after initiation of the program in Isfahan province., Materials and Methods: In this cross-sectional study, children with a primary diagnosis of CH studied. They clinically examined and their medical files were reviewed by a Pediatric Endocrinologist. Considering screening and follow-up lab data and radiologic findings the etiology of CH was determined. Screening properties of different etiologies of CH was compared., Results: In this study, 437 patients with permanent CH (PCH) were studied. Etiology of PCH in 316 (72.3%) and 121 (27.7%) of cases was thyroid dyshormonogenesis and thyroid dysgenesis, respectively. Prevalence of agenesis, ectopia, hypoplasia and hemiagenesis in thyroid dysgenetic patients was 13.3%, 6.4%, 4.3% and 3.7% respectively. Mean of thyroid stimulating hormone in screening, recall and after discontinuing treatment at 3 years of age was significantly lower in dyshormonogenetic CH patients than dysgenetic ones(P < 0.01)., Conclusion: Seven years of our experiences in CH screening program indicated that the etiology of CH in Isfahan, with a higher rate of CH, with a predominance of thyroid dyshormonogenesis is different from most of the studies world-wide and similar to other reports from Iran. The findings of the current study provide us baseline information for determination of CH pathogenesis in this region.

Background: Considering the importance to determine the reasons for the higher occurrence of congenital hypothyroidism (CH) in Iran, in this study we report the prevalence of permanent CH (PCH) in Isfahan province 7 years after initiation of CH screening program in Isfahan., Methods: In this cross-sectional study, children with a primary diagnosis of CH studied. They clinically examined and their medical files were reviewed by a pediatric endocrinologist. Considering screening and follow-up lab data, radiologic findings and the decision of pediatric endocrinologists the final diagnosis of PCH was determined., Results: A total of 464,648 neonates screened in Isfahan province. The coverage percent of the CH screening and recall rate was 98.9% and 2.1%, respectively. A total of 1990 neonates were diagnosed with primary CH. PCH was diagnosed in 410 neonates. The prevalence of PCH and transient CH (TCH) was 1 in 1133 and 1 in 294 live births. The most common etiology of CH was thyroid dyshormonogenesis., Conclusions: Though the prevalence of PCH is high, but the higher prevalence of CH in Isfahan is commonly due to cases with TCH. Hence, the necessity of determining new strategies for earlier diagnosis of patients with TCH is recommended.

Background: Congenital hypothyroidism (CH) considered a common endocrine disorder in Iran. We report the epidemiologic findings of CH screening program in Isfahan, seven years after its development, regarding the prevalence of transient CH (TCH) and its screening properties comparing with permanent CH (PCH)., Materials and Methods: In this cross-sectional study, children with primary diagnosis of CH were studied. Considering screening and follow-up lab data and the decision of pediatric endocrinologists, the final diagnosis of TCH was determined., Results: A total of 464,648 neonates were screened. The coverage percent of the CH screening and recall rate was 98.9 and 2.1%, respectively. Out of which, 1,990 neonates were diagnosed with primary CH. TCH was diagnosed in 1,580 neonates. The prevalence of TCH was 1 in 294 live births. 79.4% of patients with primary CH had TCH. Mean of screening (54.7 ± 59.0 in PCH vs 21.8 ± 28.9 in TCH), recall (56.5 ± 58.8 in PCH vs 36.6 ± 45.0 in TCH), and thyroid stimulating hormone (TSH) and mean of TSH before (2.0 ± 2.9 in PCH vs 1.6 ± 1.6 in TCH) and after (37.7 ± 29.5 in PCH vs 4.3 ± 1.9 in TCH) discontinuing treatment at 3 years of age was significantly higher in PCH than TCH (P < 0.0000)., Conclusion: The higher rate of CH in Isfahan is mainly due to the transient form of the disease. Further studies for evaluating the role of other environmental, autoimmune and/or genetic factors in the pathophysiology of the disease is warranted.

Background: This study aimed to establish a comprehensive screening and referral system for chronic non-communicable diseases (CNCD) in the routine primary health care, and to determine the prevalence of diabetes, pre-diabetes, metabolic syndrome, and dyslipidemia in adult population invited by public announcement to the Health clinics in Isfahan, Iran., Methods: This survey was conducted from March 2010, and the current paper presents data obtained until November 2011. To provide health services for prevention and control of CNCDs, with priority of type2 diabetes mellitus, Health clinics were established in different parts of Isfahan city with a population of approximately 2,100,000 in Iran. The general populations aged 30 years and above were invited to the Health clinics by public announcement., Results: A total of 198972 participants were screened. The mean age of participants was 47.8 years (48.5 men, 47.3 women), with a range of 1 to 95 years old and standard deviation of 12.3 years (12.7 men, 12.1 women). Overall, 22% of participants had impaired fasting glucose, 25% had hypercholesterolemia, 31% had hypertriglyceridemia, and 20% had metabolic syndrome., Conclusion: The high prevalence of dysglycemia and diabetes in our survey may serve as confirmatory evidence about the importance of mass screening and early diagnosis of CNCDs' risk factors. Our model of establishing Health clinics, as a comprehensive referral system in the routine primary health care can be adopted by Middle Eastern countries, where CNCDs notably diabetes are an emerging health problem.

Background. Thyroid peroxidase gene (TPO) mutations are one of the most common causes of thyroid dyshormonogenesis in patients with congenital hypothyroidism (CH). In this study, the prevalence of TPO gene mutations in patients with thyroid dyshormonogenesis in Isfahan was investigated. Methods. In this cross-sectional study, genomic DNA of 41 patients with permanent CH due to thyroid dyshormonogenesis was extracted using the salting out method. The 17 exonic regions of the TPO gene were amplified. SSCP technique was performed for scanning of the exonic regions of the TPO gene, except exon 8. DNA sequencing was performed for those with different migration patterns in SSCP by chain termination method. Exon 8 was sequenced directly in all patients. In 4 patients, all fragments were also sequenced. Results. One missense mutation c.2669G > A (NM&#95;000547.5) at exon 15 (14th coding exon) in one patient in homozygous form and seven different single nucleotide polymorphisms (SNPs) in exons 1, 7, 8, 11, and 15 of TPO gene. Conclusion. The TPO gene mutations among CH patients with dyshormonogenesis in Isfahan were less frequent in comparison with other similar studies. It may be due to the presence of other unknown gene mutations which could not be detected by SSCP and sequencing methods.

Introduction: In view of the high prevalence of Congenital Hypothyroidism (CH) in Iran, in this study we evaluated the role of iodine in the aetiology of CH by comparing urine and milk iodine concentrations in healthy and congenitally hypothyroid neonates and their mothers., Material and Methods: In a cross-sectional study, urinary iodine concentrations (UIC) in newborns with CH, as well as UIC and the milk iodine concentrations (MIC) of their mothers, were measured and compared with a control group. The lower, mid, and upper range of UIC for neonates and lactating mothers was considered to be < 150 μg/L, 150-230 μg/L, and > 230 μg/L, and lower, mid, and upper range of MIC was considered to be < 150 μg/L, 150-180 μg/L, and > 180 μg/L, respectively., Results: The median UICs in subjects with CH (n = 68) and healthy subjects (n = 179) were 300.5 and 290.5 μg/L, respectively (P > 0.05). The median UICs in the case and control groups were 150 and 130 μg/L, respectively (P > 0.05). The median MIC in the case group was higher than in the control group (210 μg/L v. 170 μg/L, P < 0.05).There was a positive correlation between newborn UIC and MIC. There was no significant correlation between newborn UIC and serum TSH, maternal UIC and maternal MIC, or newborn UIC and serum TSH., Conclusions: There is no inadequacy in iodine intake in the studied population. Iodine excess could be a possible risk factor for CH, but there were findings, such as lack of correlation between maternal MIC and UIC, and the median neonatal UIC, which was similar in the two groups, so, drawing conclusions should be done with some caution and requires further studies.