Crushing and Grinding : Practice and Problems in Kalyadi Copper Mine Concentrator

At Kalyadi concentrator plant the ROM ore is required to be reduced to 70% - 200 mesh size for liberation of valuable mineral. The metallic minerals that are mainly present in the ore are chalcopyrite, pyrite, magnetite and pyrrhotite the latter two being of minor occurance within quartzite. These minerals occur as disseminations, specks, particles, thin veinlets and concentrations. Ore is highly abrasive in nature with specfic gravity of 2.9. Ore grade varies from 0.5 to 0.8% Cu. giving an average grade of 0. 65% Cu

Birth weight and term of the gestation in pregnancies complicated by isolated oligo and isolated polyhydramnios

Background: To access the birth weight of the newborn and term of the gestation in pregnancies complicated by isolated oligo and polyhydramnios.Methods: A Hospital based study has been conducted in the Department of Obstetrics and Gynaecology, Sri Ramachandra Medical College and Research Institute, Chennai.  All the singleton pregnancies diagnosed with Isolated Oligo and Polyhydramnios were enrolled in the study. All the subjects were followed up to their delivery. Birth weight and Term of the Gestation were recorded immediately after delivery.Results: Out of 3,567 patients 32 (0.9%) and 5 (0.15%) were diagnosed as Isolated Oligo and Polyhydramnios respectively.Among 32 (0.9%) newborns of Isolated Oligohydramnios, 5 (15.62%) were Very Low Birth Weight ( 3800gms). On the other hand Preterm and Term gestations were 17 (53.12%) and 15(46.8%) respectively in this group.Among the 5 (0.15%) cases of Isolated Polyhydramnios group, Very Low Birth Weight and Low Birth Weight newborns were 1(20%) each and newborns with normal Birth weight were 3 (60%). Similarly, Preterm and Term gestations were 2(40%) and 3(60%) respectively.Conclusion:  Isolated Oligo and Polyhydramnios are associated with increased rate of Low Birth Weight (Very Low Birth Weight and Low Birth Weight) neonates and Preterm deliveries.

WILL THE TYPE OF GnRH ANALOGUE AFFECT THE EMBRYO CLEAVAGE

Aim and Objective: The present study is aimed to carry out the effect of the type of GnRH analogue on embryo cleavage. Materials and Methods:A total of 403 patients who underwent Intra Cytoplasmic sperm injection were included in the study .They were divided in to three groups. Group I- Embryos which cleaved before 27 hours after injection. Group II- Embryos which cleaved after 27 hours, Group III-Embryos which cleavaed before and after 27 hours. The effects of GnRh agonist and antagonist on embryo cleavage were compared between the three groups. Results: All the 403 patients were analysed. There was no difference in the mean age, duration of ovarian stimulation, number of oocytes retrieved, fertilization, cleavage rates and embryo quality between the three groups. Out of 403 patients, early cleavage was observed in 165 patients (40.94 %). Late cleavage was observed in 129 patients (32.01%), both early and late cleavage was observed in 109 patients(27.05%).Out of 227 patients in the agonist protocol the early cleavage was observed in 98 patients (43.17%), late cleavage was observed in 71patients (31.28%),and both early and late cleavage was observed in58 patients (25.55%). Out of 176 patients in the antagonist protocol the early cleavage was observed in 67 patients (38.07%), late cleavage was observed in 58 patients (32.95%), and both early and late cleavage was observed in 51 patients (28.98%) P 0.563. We observed there was no statistical significant difference between agonist and antagonist stimulation protocol on embryo cleavage Conclusion: The embryo cleavage was not affected by the type of GnRHanalogue used.KEYWORDS: Early cleavage; Embryo quality; Intracytoplasmic sperm injection; Ovarian stimulation

WILL THE TYPE OF GnRH ANALOGUE AFFECT THE EMBRYO CLEAVAGE

Aim and Objective: The present study is aimed to carry out the effect of the type of GnRH analogue on embryo cleavage. Materials and Methods:A total of 403 patients who underwent Intra Cytoplasmic sperm injection were included in the study .They were divided in to three groups. Group I- Embryos which cleaved before 27 hours after injection. Group II- Embryos which cleaved after 27 hours, Group III-Embryos which cleavaed before and after 27 hours. The effects of GnRh agonist and antagonist on embryo cleavage were compared between the three groups. Results: All the 403 patients were analysed. There was no difference in the mean age, duration of ovarian stimulation, number of oocytes retrieved, fertilization, cleavage rates and embryo quality between the three groups. Out of 403 patients, early cleavage was observed in 165 patients (40.94 %). Late cleavage was observed in 129 patients (32.01%), both early and late cleavage was observed in 109 patients(27.05%).Out of 227 patients in the agonist protocol the early cleavage was observed in 98 patients (43.17%), late cleavage was observed in 71patients (31.28%),and both early and late cleavage was observed in58 patients (25.55%). Out of 176 patients in the antagonist protocol the early cleavage was observed in 67 patients (38.07%), late cleavage was observed in 58 patients (32.95%), and both early and late cleavage was observed in 51 patients (28.98%) P 0.563. We observed there was no statistical significant difference between agonist and antagonist stimulation protocol on embryo cleavage Conclusion: The embryo cleavage was not affected by the type of GnRHanalogue used.KEYWORDS: Early cleavage; Embryo quality; Intracytoplasmic sperm injection; Ovarian stimulation

Molecular Characterization of the Gene of Vertically Transmitted HIV-1 Strains in Children with Virological Failure.

HIV-1 gene sequences were analyzed from 77 HIV-1 positive children infected perinatally and exhibiting virological failure (VF). Viral subtyping, phylogenetic analysis, and genotypic drug resistance analysis were carried out on samples collected before start of anti retroviral treatment (ART) (baseline, BL), and at 12 months post-ART initiation (M12). Subtype C was found to be most predominant, seen in 75 of the 77 (97.4%) children. The level of pretreatment drug resistance (PDR) was 14% among these children. At BL, K103N (5), E138A/G (4), and M184V (3) were the most common mutations. At M12 the prevalence of any resistance-associated mutation (RAM) (acquired drug resistance/ADR) was 81.8% (63/77). Dual class resistance mutations were seen in 64% (49/77) of children. M184V/I, K103N/S, and Y181C were the most commonly occurring mutations, seen in 76%, 51%, and 36% children. RAMs to the second-generation non-nucleoside reverse transcriptase inhibitors (NNRTI), etravirine (ETR) and rilpivirine (RPV), were seen in 40.2% (31/77) and 48.05% (37/77) of the children, respectively. Our findings reveal similar prevalence rates of PDR and ADR in children with VF as reported in other studies. Occurrence of ETR and RPV resistance associated mutations (RAMs) is of concern and highlights the need for timely switch of regimens guided by genotypic resistance testing in perinatally infected children from India

BOBMEX: the Bay of Bengal monsoon experiment

The first observational experiment under the Indian Climate Research Programme, called the Bay of Bengal Monsoon Experiment (BOBMEX), was carried out during July-August 1999. BOBMEX was aimed at measurements of important variables of the atmosphere, ocean, and their interface to gain deeper insight into some of the processes that govern the variability of organized convection over the bay. Simultaneous time series observations were carried out in the northern and southern Bay of Bengal from ships and moored buoys. About 80 scientists from 15 different institutions in India collaborated during BOBMEX to make observations in most-hostile conditions of the raging monsoon. In this paper, the objectives and the design of BOBMEX are described and some initial results presented. During the BOBMEX field phase there were several active spells of convection over the bay, separated by weak spells. Observation with high-resolution radiosondes, launched for the first time over the northern bay, showed that the magnitudes of the convective available potential energy (CAPE) and the convective inhibition energy were comparable to those for the atmosphere over the west Pacific warm pool. CAPE decreased by 2-3 kJ kg-1 following convection, and recovered in a time period of 1-2 days. The surface wind speed was generally higher than 8 m s-1. The thermohaline structure as well as its time evolution during the BOBMEX field phase were found to be different in the northern bay than in the southern bay. Over both the regions, the SST decreased during rain events and increased in cloud-free conditions. Over the season as a whole, the upper-layer salinity decreased for the north bay and increased for the south bay. The variation in SST during 1999 was found to be of smaller amplitude than in 1998. Further analysis of the surface fluxes and currents is expected to give insight into the nature of coupling

Global Retinoblastoma Presentation and Analysis by National Income Level.

Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. Objectives: To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. Design, Setting, and Participants: A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Main Outcomes and Measures: Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. Results: The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (n = 3685 [84.7%]) were from low- and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 [62.8%]), followed by strabismus (n = 429 [10.2%]) and proptosis (n = 309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]). Conclusions and Relevance: This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs

The global retinoblastoma outcome study : a prospective, cluster-based analysis of 4064 patients from 149 countries

DATA SHARING : The study data will become available online once all analyses are complete.BACKGROUND : Retinoblastoma is the most common intraocular cancer worldwide. There is some evidence to suggest that major differences exist in treatment outcomes for children with retinoblastoma from different regions, but these differences have not been assessed on a global scale. We aimed to report 3-year outcomes for children with retinoblastoma globally and to investigate factors associated with survival. METHODS : We did a prospective cluster-based analysis of treatment-naive patients with retinoblastoma who were diagnosed between Jan 1, 2017, and Dec 31, 2017, then treated and followed up for 3 years. Patients were recruited from 260 specialised treatment centres worldwide. Data were obtained from participating centres on primary and additional treatments, duration of follow-up, metastasis, eye globe salvage, and survival outcome. We analysed time to death and time to enucleation with Cox regression models. FINDINGS : The cohort included 4064 children from 149 countries. The median age at diagnosis was 23·2 months (IQR 11·0–36·5). Extraocular tumour spread (cT4 of the cTNMH classification) at diagnosis was reported in five (0·8%) of 636 children from high-income countries, 55 (5·4%) of 1027 children from upper-middle-income countries, 342 (19·7%) of 1738 children from lower-middle-income countries, and 196 (42·9%) of 457 children from low-income countries. Enucleation surgery was available for all children and intravenous chemotherapy was available for 4014 (98·8%) of 4064 children. The 3-year survival rate was 99·5% (95% CI 98·8–100·0) for children from high-income countries, 91·2% (89·5–93·0) for children from upper-middle-income countries, 80·3% (78·3–82·3) for children from lower-middle-income countries, and 57·3% (52·1-63·0) for children from low-income countries. On analysis, independent factors for worse survival were residence in low-income countries compared to high-income countries (hazard ratio 16·67; 95% CI 4·76–50·00), cT4 advanced tumour compared to cT1 (8·98; 4·44–18·18), and older age at diagnosis in children up to 3 years (1·38 per year; 1·23–1·56). For children aged 3–7 years, the mortality risk decreased slightly (p=0·0104 for the change in slope). INTERPRETATION : This study, estimated to include approximately half of all new retinoblastoma cases worldwide in 2017, shows profound inequity in survival of children depending on the national income level of their country of residence. In high-income countries, death from retinoblastoma is rare, whereas in low-income countries estimated 3-year survival is just over 50%. Although essential treatments are available in nearly all countries, early diagnosis and treatment in low-income countries are key to improving survival outcomes.The Queen Elizabeth Diamond Jubilee Trust and the Wellcome Trust.https://www.thelancet.com/journals/langlo/homeam2023Paediatrics and Child Healt

Pregnancy outcome of assisted reproductive technology cycle in patients with hypogonadotropic hypogonadism

CONTEXT: Ovulation induction in patients with hypogonadotropic hypogonadism (HH) is a challenge to the treating physician. The threshold for ovarian response in HH may differ substantially from that of normal patients. To reach that threshold levels of follicle stimulating hormone, in a step-up protocol longer duration of stimulation is required in some cases so as to prevent multiple pregnancy and to eliminate the risk of ovarian hyperstimulation syndrome. AIM: To evaluate the duration of stimulation, quality of oocytes, and embryo, and the pregnancy outcome in the assisted reproductive technology (ART) cycles in patients with HH. MATERIALS AND METHODS: Over the period of 4 years, we had 14 patients with HH in whom 21 cycles of ovulation induction were done. Of these 7 patients underwent oocyte retrieval and intracytoplasmic sperm injection (ICSI). We present a retrospective study of these 7 patients who underwent ART to evaluate the duration of stimulation, quality of oocytes and embryo, and the pregnancy outcome. RESULTS: In the study group on ovulation induction with gonadotropins, only one patient had the duration of stimulation of the standard 12 days, the remaining 6 patients took ≥12 days to respond to stimulation (maxium being 54 days). Mean ET in these patients was 8.9 mm. Six patients had >70% good quality MII oocytes. One patient responded poorly and had only 2 good quality MII oocytes (50%). After ICSI procedure, resultant embryos were of grade 1 and 2 in all the patients irrespective of the duration of stimulation. Fertilization rate in these patients was 85% (except in one 50% fertilization rate), and the cumulative pregnancy rate was 68.6%. CONCLUSION: In the patients with HH the quality of oocytes and embryos, and the pregnancy rate is not affected even if the duration of stimulation is prolonged

Kinetics & Mechanism of Acid Bromate Oxidation of Aliphatic, Aralkyl & Alicyclic Ketones

288-291Oxidation of a few typical aliphatic, aralkyl and alicyclic ketones with acid bromate has been investigated. The reaction is first order in both [bromate] and [ketone]. The rate increases with increase in [acid] of the medium. Ionic strength effect is marginal but, the oxidation rates are susceptible to change in dielectric constant of the medium. The mechanism proposed involves the attack of acid bromate on the enol-form of the ketone in the rate-determining, formation of an intermediate followed by a fast decomposition to products. The order of reactivities is: (i) ethyl methyl ketone > n-propyl methyl ketone > dimethyl ketone for simple aliphatic ketones; (ii) acetophenone > propiophenone > butyrophenone for aralkyl ketones; and (iii) cyclooctanone > cyclohexanone > cycloheptanone for alicyclic ketones. Thermodynamic parameters have been evaluated and discussed