Theoretical study of Spinel based Transition Metal Oxides is reported. The Density Functional Theory approach is adopted for computational investigation using LAPW code. The structural, elastic properties of (XAl2O4 for X=Mg, Mn, Fe, Co, Ni, Cu, Zn), (MGa2O4 for M=Mg, Mn, Fe, Co, Ni, Cu, Zn, Cd), (NIn2O4 for N=Mg, Zn, In) & (ZnP2O4 for P=V, Cr, Fe, Rh, Sn) along with electronic & magnetic properties of cubic spinel oxides (XAl2O4) and (MGa2O4) have calculated. The calculated structural parameters conform to other experimental and theoretical evidences. Fulfillment of elastic stability criteria proves the reliability of the reported data. The calculated elastic constants show that all materials abide its stability opposing elastic deformations and the Cauchy’s pressure confirms the dynamical stability of these materials. The high values of bulk moduli show the hardness of these materials while the Young moduli data reveal that MgAl2O4 is the stiffer material among all. Further, Poisson’s ratios testify the compressibility, connote stableness to external deformation of these materials and reveal dominance of central forces being the interatomic forces. Out of 24 materials, only 05 are brittle and the rest are ductile with elastic anisotropy. MgAl2O4 is the most brittle and CdGa2O4 is the most ductile material. The electronic structure (Total DOS) show all XAl2O4, MGa2O4 (M=Fe, Co, Zn, Cd) have antiferromagnetic, NiGa2O4 & CuGa2O4 have FM state and the valence near Fermi level due to the transition metal 3d state. The calculation of direct exchange energy Δx(d) shows that the exchange mechanism of electrons is dominant in introducing magnetism and enormous exchange splitting is observed in these materials. The ferromagnetism in the group MGa2O4 of spinel oxide compounds is due to hybridization between the electrons in the 3d-states cation and 2p states anion. Appearance of magnetic moments in these materials is due to unpaired electrons in 3d states of Transition metal ions. The negative value of indirect exchange energy confirms the magnetism by spin of electrons.
تنقید: تنقید عربی زبان کا لفظ ہے۔ جس کے عام معنی اخراج کے ہیں۔نورالغات میں مولوی نورالحسن نے اس کی تعریف یوں کی ہے: "کھوٹا کھرا پرکھنا یا جانچ کرنا۔ایسی جانچ جو ضعیف اور مشکوک چیزوں کو الگ کردے یعنی اچھے اور برے کی تمیز کرنا" اردو ادب میں اس کے مترادف لفظ تنقید استعمال ہوتا ہے لیکن انگریزی میں اس کے مترادف لفظ Criticism استعمال ہوتا ہے۔بعض اوقات اس کے لیے نقد یا انتقاد کے الفاظ بھی استعمال کیے جاتے ہیں۔حامداللہ افسرنے اسی تناظر میں اپنی کتاب "تنقیدی اصول و نظریے" پہلے نقد الادب کے نام سے شائع کی۔ان کی ایک کتاب" انتقاد" اور دوسری "اصول انتقاد ادبیات" کے نام سے شائع ہوئی لیکن ہمارے معاشرے میں اکثریت کے ساتھ چلنا پڑتا ہے۔لہذا حامداللہ افسر اس نتیجے پر پہنچے کہ چونکہ اکثریت اس طرف جا رہی ہے تو میں چونکہ اس کو نام نقد یا انتقاد دینا چاہ رہا ہوں تو شاید کامیاب نہ ہو سکوں تو انہوں نے اپنی کتاب کا نام تبدیل کیا اور اسی کتاب کو پھر شائع کیا اور اس کا نام رکھا" تنقیدی اصول و نظریے"۔ حامد اللہ افسر کی اس کے بارے میں رائے یہ ہے کہ وہ کیوں اس طرف آئے۔وہ کہتے ہیں : "لفظ تنقید عربی صرف و نحو کے اعتبار سے صحیح نہیں ہے جس کی جگہ نقد یا انتقاد ہونا چاہیئے۔لیکن اردو ادب میں اب یہ لفظ رائج ہو گیا ہے۔اس کی جگہ کسی دوسریلفظ کا استعمال مناسب نہ ہوگا۔جہاں تک اردو زبان کا سوال ہے اسے صحیح سمجھنا چاہیئے۔" ادبی اصطلاحات کا تعارف" کے صفحہ 167 پر مصنف ابوالاعجاز صدیقی کی رائے یہ ہے : "تنقید اصل میں کسی بھی فن پارے کو ذاتی پسندو ناپسند سے بالا ہو کر پرکھنے اور جانچنیکا نام ہے۔تنقید کسی ادب کے فنی محاسن کی پرکھ کا نام ہے"
During the period of total containment during the Covid-19 pandemic; our department became the sole treatment center for all surgical emergencies. The influx of many patients made the task very difficult for the surgeon. This is a 3-month descriptive prospective study in the visceral surgery department at the Analankininina Toamasina University Hospital Center. Of the 81 patients hospitalized during the study, 32 patients were admitted for digestive surgery emergency, i.e. 39.50%. The mean age was 34.87 years with a sex ratio of 1.66, predominantly male. Abdominal pain occupied 43.75% of the reason for consultation, the most frequent pathologies were acute intestinal obstruction (18.75%) and acute appendicitis (18.75%). An exploratory laparotomy is performed on 40.62% of patients. Many patients were operated on for proctologic emergency (18.75%). The average length of hospitalization is 4.18 days. The visceral emergencies are present despite the presence of the Covid-19 pandemic and the activities of the health personnel are uninterrupted.
BACKGROUND AND OBJECTIVES: The rare single gene mutations resulting in early onset extreme obesity and hyperphagia have led to the discovery of the central leptin-dependent melanocortin signaling regulating energy homeostasis, food intake and body weight. Energy imbalance is known to influence other physiological mechanisms such as neuroendocrine, reproductive, metabolic and immune functions. Excessive obesity has also been shown to impact bone formation and mineralization as evidenced mainly through imaging techniques. However, the effects of obesity on bone metabolism have remained controversial and often conflicting in various reports presumably due to the heterogeneity of the disease and differences in age, sex and ethnicity of subjects under investigation. Monogenic obesity provides an exceptionally unique paradigm to study the physiological phenotype in relation to specific energy-impaired states in the human. In view of the foregoing, the present study aims to first identify cases of monogenic obesity by screening, a group of children with early onset severe obesity from consanguineous families and subsequently to assess bone metabolism in affected individuals using specific bone turnover biomarkers. In addition, associated changes in metabolic hormone levels are recorded. MATERIALS AND METHODS: Initially, 130 unrelated severely obese children from consanguineous families were recruited from the central Punjab province of Pakistan. The subjects, 0.3-13 years of age, had a body weight percentile >97 and a BMI SDS for age ≥3.0. Anthropometric data and information about family and medical history were recorded. In the first phase of investigation, DNA of all subjects was screened for leptin (LEP) and melanocortin-4 receptor (MC4R) genes mutations, in the coding regions. Subjects found negative for these mutations were subsequently screened by microdroplet PCR targeted against a panel of 27 known obesity associated genes and next generation sequencing. Serum from subjects identified with monogenic obesity and from a control group of 26 age-matched children with normal body weight, was analyzed for bone specific turnover biomarkers, osteocalcin (OC), osteopontin (OPN), osteoprotegerin (OPG) and sclerostin (SOST) using multiplex analyte profiling. In addition, serum levels of leptin, insulin and cortisol were assessed by enzyme linked immunosorbent assay (ELISA). Thyroid stimulating hormone (TSH) and thyroid hormones (T3 and T4) were determined by electro-chemiluminescence immunoassay (ECLIA). RESULTS: The two-step genetic analysis of 130 children with morbid obesity, identified 42 probands with lossof- function homozygous mutations in LEP, leptin receptor (LEPR), or MC4R genes. Amongst these, 23 probands were identified with mutations in LEP, 11 with mutations in LEPR and 8 children with mutations in the MC4R gene. Eleven of the 18 variants identified in the 3 genes associated with obesity, are reported here for the first time. Bone metabolism in affected subjects, was assessed by specific serum bone turnover markers. Serum levels of bone formation indicators, osteocalcin and osteopontin, were significantly lower in LEP and LEPR deficient subjects compared with controls. In contrast, in MC4R deficient children, levels of these two biomarkers were remarkably raised over values observed for all other groups. Serum concentration of bone resorption biomarkers, osteoprotegerin and sclerostin, for the three mutant groups were not remarkably different from the values of normal weight subjects. However, mean sclerostin levels in children with MC4R mutations tended to be lower than those with LEP and LEPR defects and of the control group. As expected, leptin levels were undetectable in subjects with LEP mutations. Hyperleptinemia was more pronounced in subjects with LEPR deficiency compared to those with MC4R deficiency. Insulin levels though raised in all affected subjects were significantly higher in children with MC4R deficiency whereas serum cortisol concentrations were significantly elevated in LEP deficient children compared to all other groups. Interestingly, TSH, T3 and T4 levels in all affected subjects were unremarkable and within the normal range. CONCLUSIONS: The present data in conformity with previous reports in this population, demonstrate a relatively high prevalence (32%) of monogenic obesity among severely obese children. Eighteen different known or novel loss-of-function mutations were identified in LEP, LEPR and MC4R genes. Assessment of bone metabolism in affected subjects revealed a consistent deficit in bone formation in subjects with leptin or leptin receptor deficiency. These results indicate an impaired osteogenic activity and further support a substantial role of leptin in bone homeostasis. Remarkably, opposite alterations in bone turnover presumably due to an up-regulation of bone formation, were associated with MC4R deficiency. The present data advocate investigation of bone health preferably using a combination of imaging and biochemical techniques in cases of severe obesity for individualized management or treatment.