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The study area belongs to the Singhbhum metamorphic belt of Jharkhand, situated in the eastern part of India. The spatial distribution of the index minerals in the pelitic schists of the area shows Barrovian type of metamorphism. Three isograds, viz. garnet, staurolite and sillimanite, have been delineated and the textural study of the schists has revealed a time relation between crystallization and deformation. Series of folds with shifting values of plunges in the supracrustal rocks having axial-planar schistosity to the folds have been widely cited. Development of these folds could be attributed to the second phase of deformation. In total, two phases of deformation, D1 and D2, in association with two phases of metamorphism, M1 and M2, have been lined up in the study area. Chemographic plots of reactant and product assemblages corresponding to various metamorphic reactions suggest that the pattern of metamorphic zones mapped in space is in coherence with the temporal-sequential change during prograde metamorphism. The prograde P–T evolution of the study area has been obtained using conventional geothermobarometry, internally consistent winTWQ program and Perple_X software in the MnNCKFMASHTO model system. Our observations suggest that the progressive metamorphism in the area is not related to granitic intrusion or migmatization but that it was possibly the ascending plume that resulted in the M1 phase of metamorphism followed by D1 deformation. The second and prime metamorphic phase, M2, with its possible heat source generated by crustal overloading, was preceded by D1 and it lasted until late- to post-D2 deformation.
A cross-sectional study was conducted from 2014 to 2017 in 13 organised pig farms located in eight states of India (Northern, North-Eastern and Southern regions) to identify the risk factors, pathotype and antimicrobial resistance of Escherichia coli associated with pre- and post-weaning piglet diarrhoea. The data collected through questionnaire survey were used to identify the risk factors by univariable analysis, in which weaning status, season, altitude, ventilation in the shed, use of heater/cooler for temperature control in the sheds, feed type, water source, and use of disinfectant, were the potential risk factors. In logistic regression model, weaning and source of water were the significant risk factors. The piglet diarrhoea prevalence was almost similar across the regions. Of the 909 faecal samples collected (North – 310, North-East – 194 and South – 405) for isolation of E. coli, pathotyping and antibiotic screening, 531 E. coli were isolated in MacConkey agar added with cefotaxime, where 345 isolates were extended spectrum β-lactamase (ESBL) producers and were positive for blaCTX-M-1 (n = 147), bla TEM (n = 151), qnrA (n = 98), qnrB (n = 116), qnrS (n = 53), tetA (n = 46), tetB (n = 48) and sul1 (n = 54) genes. Multiple antibiotic resistance (MAR) index revealed that 14 (2.64%) isolates had MAR index of 1. On the virulence screening of E. coli, 174 isolates harboured alone or combination of Stx1, Stx2, eaeA, hlyA genes. The isolates from diarrhoeic and post-weaning samples harboured higher number of virulence genes than non-diarrhoeic and pre-weaning. Alleviating the risk factors might reduce the piglet diarrhoea cases. The presence of multidrug-resistant and ESBL-producing pathogenic E. coli in piglets appears a public health concern.
A cross-sectional study on six dairy farms was conducted to ascertain the occurrence of carbapenem-resistant Escherichia coli in calves. Two-hundred and seventy-nine isolates of E. coli were recovered from 90 faecal samples from apparently healthy (45) and diarrhoeal (45) calves. The isolates were screened for phenotypic susceptibility to carbapenems and production of metallo β-lactamase, as well as five carbapenemase resistance genes by PCR, and overexpression of efflux pumps. Eighty-one isolates (29.03%) were resistant to at least one of three carbapenem antibiotics [meropenem (23.30%), imipenem (2.15%) and ertapenem (1.43%)], and one isolate was positive for the blaVIM gene which was located on an Incl1 plasmid of a novel sequence type (ST 297) by multilocus sequence typing. The majority (83.95%) of isolates had an active efflux pump. Calves housed on concrete floors were approximately seven times more likely to acquire meropenem-resistant isolates than those housed on earthen floors (95% CI 1.27–41.54). In India, carbapenem drugs are not used in food animal treatment, hence carbapenem-resistant strains in calves possibly originate from the natural environment or human contact and is of public health importance. To our knowledge, this is the first report of blaVIM carbapenemases gene in calves from India.
Depression frequently co-occurs with disorders of glucose and insulin homeostasis (DGIH) and obesity. Low-grade systemic inflammation and lifestyle factors in childhood may predispose to DGIH, obesity and depression. We aim to investigate the cross-sectional and longitudinal associations among DGIH, obesity and depression, and to examine the effect of demographics, lifestyle factors and antecedent low-grade inflammation on such associations in young people.
Using the Avon Longitudinal Study of Parents and Children birth cohort, we used regression analyses to examine: (1) cross-sectional and (2) longitudinal associations between measures of DGIH [insulin resistance (IR); impaired glucose tolerance] and body mass index (BMI) at ages 9 and 18 years, and depression (depressive symptoms and depressive episode) at age 18 years and (3) whether sociodemographics, lifestyle factors or inflammation [interleukin-6 (IL-6) at age 9 years] confounded any such associations.
We included 3208 participants. At age 18 years, IR and BMI were positively associated with depression. These associations may be explained by sociodemographic and lifestyle factors. There were no longitudinal associations between DGIH/BMI and depression, and adjustment for IL-6 and C-reactive protein did not attenuate associations between IR/BMI and depression; however, the longitudinal analyses may have been underpowered.
Young people with depression show evidence of DGIH and raised BMI, which may be related to sociodemographic and lifestyle effects such as deprivation, smoking, ethnicity and gender. In future, studies with larger samples are required to confirm this. Preventative strategies for the poorer physical health outcomes associated with depression should focus on malleable lifestyle factors.
Background: Children diagnosed with medulloblastoma (MB) that are refractory to upfront therapy or experience recurrence have very poor prognoses. Reports of phase I and II studies for these children exist, but bear significant treatment related morbidity and mortality. Methods: A retrospective review of children diagnosed with a pediatric MB from 2002-2015 from the McMaster Pediatric Brain Tumour Study Group (PBTSG) captured a number of pediatric recurrent MB. Results: Over the 13-year period, 31 children with a histological diagnosis of MB were treated. At two years, 21 (67.7%) of 31 patients were free of recurrence and 25 (80.6%) survived. Thirteen children had recurrent or treatment refractory MB. mean time to recurrence was 14.6 months. The mean follow-up for survivors of recurrent MB was 4.0 years. In 3 recurrent MB, the disease had significantly progressed and the patients palliated. For the remaining children, therapy offered included surgery, radiation, and chemotherapy agents either in isolation or in varying combinations. Conclusions: Recurrent MB in our cohort carried a poor prognosis despite administration of salvage therapy. Though there is standardization of the upfront treatment exists, we observed great heterogeneity in the treatment of our 13 patients experiencing recurrence. A greater understanding of the biology of recurrent MB has the potential to guide salvage therapy.
Introduction: The GridlockED game is a serious game aimed at teaching junior learners about flow and organization in the emergency department(ED). With serious games, the mechanism of learning is thought to be via the gameplay experience. Objectives built into gameplay are aimed at teaching players about a specific concept; in this case, we hoped to teach players about interprofessional collaboration and basic mechanics that drive flow in the ED. However, before a player can be taught, he or she must be engaged and have a positive gameplay experience. From the GridlockED gameplay, we aim to explore how a players gameplay experience related to observed actions while playing the game, including participating in decision making and keeping the team organized. Methods: From April-August 2017, participants were invited to play 4 turns of a GridlockED game session. They were video recorded during gameplay. After playing the game, they were surveyed using the previously derived Game Experience Questionnaire (GEQ) to measure their gameplay experience. The videos were reviewed by two research team members (SH, EJ), tallying various observed game actions. We conducted Pearson correlation between players GEQ total score and their observed actions. Results: A total of 32 participants (13 attendings, 5 senior residents, 10 junior residents, and 4 nurses) played the game. The average total GEQ was 67.2/132 (SD=10.7), suggesting most players had a moderately good gameplay experience. The total GEQ score correlated with component subscores within the questionnaire. Overall observed activity correlated well with each observed action subtype. However, the GEQ total score did not correlate significantly with the total observed action (Pearsons r=0.18,p=0.32). GEQ total score was found to be moderately correlated to an observation that a player participated in determining strategy during gameplay (r=0.36,p=0.04). There was a moderate negative correlation between determining strategy during gameplay and teaching about the game (r=-0.37,p=0.04) or emergency medicine concepts (r=-0.47,p<0.01). Conclusion: The GEQ is internally consistent, but does not have a strong relationship to observed actions, suggesting that game experience does not necessarily correlate with observable actions. This suggests that players may be intellectually stimulated or engaged without necessarily completing any observable actions during gameplay.
Skilled nursing home facilities (SNFs) house a vulnerable population frequently exposed to respiratory pathogens. Our study aims to gain a better understanding of the transmission of nursing home-acquired viral respiratory infections in non-epidemic settings. Symptomatic surveillance was performed in three SNFs for residents exhibiting acute respiratory symptoms. Environmental surveillance of five high-touch areas was performed to assess possible transmission. All resident and environmental samples were screened using a commercial multiplex polymerase chain reaction platform. Bayesian methods were used to evaluate environmental contamination. Among nursing home residents with respiratory symptoms, 19% had a detectable viral pathogen (parainfluenza-3, rhinovirus/enterovirus, RSV, or influenza B). Environmental contamination was found in 20% of total room surface swabs of symptomatic residents. Environmental and resident results were all concordant. Target period prevalence among symptomatic residents ranged from 5.5 to 13.3% depending on target. Bayesian analysis quantifies the probability of environmental shedding due to parainfluenza-3 as 92.4% (95% CI: 86.8–95.8%) and due to rhinovirus/enterovirus as 65.6% (95% CI: 57.9–72.5%). Our findings confirm that non-epidemic viral infections are common among SNF residents exhibiting acute respiratory symptoms and that environmental contamination may facilitate further spread with considerable epidemiological implications. Findings further emphasise the importance of environmental infection control for viral respiratory pathogens in long-term care facilities.
Measurement of Excitation Functions and their Analysis
In the introductory part of this monograph, it has already been mentioned that various interesting phenomena are associated with heavy ion interactions; they have attracted the attention of many researchers during the last couple of decades. In heavy ion reactions, when the projectile energy is more than the Coulomb barrier, the fusion of incident ion and target nucleus is the most likely process. The composite nucleus so formed is excited and is likely to decay initially via particle emission; when the excitation energy decreases, it decays by emitting gamma radiations. Such reactions in which the projectile completely fuses with the target nucleus are referred to as the complete fusion (CF) reactions, as already mentioned in earlier chapters. These complete fusion reactions are dominant at energies slightly above the Coulomb barrier. On the other hand, at considerably higher energies, the interaction between the incident and the target heavy ions proceeds in a different way; only a part of the incident ion fuses with the target nucleus while the remaining unfused part moves on without any interaction. This is referred to as incomplete fusion (ICF), which is likely to dominate at considerably higher incident energies. However, in recent years, it has been observed that incident ions such as 12C and 16O that have an alpha cluster structure exhibit a significant contribution of incomplete fusion (ICF) even at low energies where the CF is expected to dominate. Further, in some recent experiments where non-alpha cluster beams like 19F were used, significant contributions by ICF were observed. With the objective to study the dynamics of complete and incomplete fusion reactions in heavy ion interactions in a variety of projectile–target combinations, several experiments have been carried out using both alpha cluster as well as non-alpha cluster projectiles. Since a direct evidence of incomplete fusion may be obtained from the measurement of the excitation function of a specific reaction channel, excitation functions for a large number of reaction channels have been measured using the stacked foil activation technique. Table 4.1 lists the systems for which excitation functions have been measured, along with the energy range of study and the height of the Coulomb barrier for each system. The specified energy range covers from near the Coulomb barrier to well above it for each system.
The study of incomplete fusion (ICF) reactions in heavy ion (HI) interactions at energies below 10 MeV per nucleon is a topic of resurgent interest. At such low energies, near and/or just above the fusion barrier, the complete fusion (CF) of the interacting ions is expected to be the most dominant process; however, experiments carried out during the last decade or so have indicated that a significant part of the interaction proceeds through ICF process. Some theories have been proposed to explain the process of incomplete fusion but none of them could successfully reproduce the experimental data at energies < 10 MeV/A. In order to understand the dynamics of such low energy ICF processes and to develop a viable theoretical frame work, our group carried out extensive and complementary experiments on the topic during the last decade or so. The monograph presents the details of these experiments and the analysis of the data.
The presentation has five chapters; Chapter-1 gives a historical background of the subject and discusses the motivation for the work. Chapter-2, entitled ‘Theoretical Tools, Reaction Mechanism and Computer Codes’ is intended to develop a sound theoretical background of the subject. Important features of computer codes available in the market for theoretical simulation are discussed in this chapter. All experimental details, including the methodology, experimental setups, formulations used for data reduction etc., are given in Chapter-3. The Chapter-4, entitled ‘Measurements’ contains the details of the measurements of Excitation Functions (EFs), Recoil Range Distributions (RRDs), Angular Distributions (ADs), Spin Distributions (SDs) and Feeding Intensity Profiles (FIPs) of reaction residues. Each measurement is discussed in detail and the recorded experimental data is presented both in tabular form as well as in graphical form. Chapter-5, is ‘Results and Conclusions’ which provides a detailed discussion of the results obtained from the critical analysis and evaluation of the data obtained in the present set of experiments. Conclusions regarding the dependence of ICF component on various entrance channel parameters, presented in this chapter may be of considerable value in developing a theoretical frame work for HI reactions at energies below 10 MeV per nucleon. The experiments detailed in this document were carried out by our research group at the Physics Department, Aligarh Muslim University, Aligarh, India, in collaboration with members of the Nuclear Physics Group of the Inter University Accelerator Centre (IUAC), New Delhi, India.
Though the concept of the nucleus and the subsequent evolution of nuclear physics are credited to Rutherford, the earlier discovery of radioactivity by A. Henri Becquerel, Pierre and Marie Curie (1896–1898) played the most crucial role in these developments. The discovery of radioactivity opened up the way to new techniques of exploring subatomic systems – for example, by bombarding them with fast moving charged particles, a technique which is still in use, and used more vigorously now, even after hundred years.
In 1898, Pierre and Marie Curie succeeded in isolating significant amounts of two new elements from pitchblende, a uranium ore. They named the two elements polonium and radium. These new elements were found to undergo spontaneous self-destruction by emitting mysterious radiations. Passing of the collimated beam of these radiations through electric and magnetic fields revealed that they are made up of three components: negatively charged components, called beta particles; neutral components of electromagnetic waves of very short wavelength or gamma rays and a third component of positively charged particles. The negatively charged beta particles were identified as electrons, while the Curies established that the positively charged particles were doubly-ionized helium atoms, called alpha particles. The average kinetic energies of these alpha particles, beta particles and neutral gamma rays had different values for different radioactive sources. Radium and polonium, the two natural radioactive sources, emit alpha particles of energies in the range of 5 to 7 MeV. Rutherford, in his famous alpha scattering experiments, actually carried out by Geiger and Marsden, bombarded thin metallic foils by a collimated beam of alpha particles obtained from radium. In these experiments, it was observed that, on an average, one to five alpha particles out of about 20,000 particles, get scattered by more than 90°. Rutherford concluded that this is possible only if the target atoms have very small volumes at their centres where total positive charge and almost all mass of the atom are concentrated. Rutherford named this small volume as the nucleus of the atom, a term he borrowed from biological science. The layout of the experimental setup used by Rutherford is shown in Figure 1.1. The alpha particle source (radium) was kept in a lead box with a small hole to get the collimated beam.
An up-to-date text, covering the concept of incomplete fusion (ICF) in heavy ion (HI) interactions at energies below 10 MeV/ nucleon. Important concepts including the exciton model, the Harp Miller and Berne model, Hybrid model, Sum rule model, Hot spot model and promptly emitted particles model are covered in depth. It studies the ICF and PE-emission in heavy ion reactions at low energies using off-beam and in-beam experimental techniques. Theories of complete fusion (CF) of heavy ions based on Compound Nucleus (CN) mechanism of statistical nuclear reactions, details of the Computer code PACE4 based on CN mechanism, pre-equilibrium (PE) emission, modeling of (ICF) and their limits of application are discussed in detail.
As has been mentioned in the introductory chapter, the initial interaction between a projectile and the target may result in the formation of an excited composite system from which nucleons or clusters may be emitted before a completely fused compound nucleus is formed. Such a process is generally referred to as the pre-compound emission (in case of nucleonic emissions) or incomplete fusion (when cluster emission takes place). Incomplete fusion/PE-emissions become more important as the incident beam energy increases; in fact, they become dominant at energies above 15 MeV/n. The measurement and analysis of excitation functions for the population of reaction residues may provide valuable information regarding the dynamics of incomplete fusion reactions. The resulting product nucleus of incomplete fusion has a momentum that is severely reduced as compared to the residues of complete fusion events. The measurement and analysis of momentum transfer via recoil range distribution is one of the most direct and irrefutable method of identifying incomplete fusion events. Details of the measurement of linear recoil range distributions (RRD) will be discussed later in the chapter. In incomplete fusion (ICF), residues recoil before the establishment of a thermodynamic equilibrium, and therefore, carry information about the initial system parameters that is reflected in the angular distribution of residues. Details of the measurement and analysis of residue angular distributions will also be presented in this chapter. In a typical experiment, residues are formed via complete fusion as well as via incomplete fusion processes. The product residues of complete fusion carry larger excitation energy and higher spin angular momentum when compared to the residues populated via incomplete fusion. This difference in their properties affects the spin distributions of their excited levels. In order to further investigate such systems and study the role of input angular momenta in ICF reactions, in-beam experiments involving particle–gamma coincidence method have been performed. Details of these experiments will be presented in the following sections. In recent years, incomplete fusion reactions have been observed even at energies as low as 3 – 7 MeV/n, where only complete fusion is likely to dominate. The present monograph deals with the description of such reactions in the low energy regime.