Time-evolution of ionization and heating around first stars and miniquasars

A one dimensional radiative transfer code is developed to track the ionization and heating pattern around the first miniquasars and Population III stars. The code follows the evolution of the ionization of the species of hydrogen and helium and the intergalactic medium temperature profiles as a function of redshift. The radiative transfer calculations show that the ionization signature of the first miniquasars and stars is very similar yet the heating pattern around the two is very different. Furthermore, the first massive miniquasars (~>10^5 M_{sun}) do produce large ionized bubbles around them, which can potentially be imaged directly using future radio telescopes. It is also shown that the ionized bubbles not only stay ionized for considerable time after the switching off of the source, but continue to expand for a short while due to secondary collisions prompted by the X-ray part of their spectra. Varying spectral shapes also produced sizable variations in ionized fraction and temperature profile. We also compare the radiative transfer results with the analytical approximation usually adopted for heating by miniquasars and find that, because of the inadequate treatment of the He species, the analytical approach leads to an underestimation of the temperature in the outer radii by a factor ~5. Population III stars - with masses in the range of 10 - 1000 M_{sun} and modelled as blackbodies at a temperature of 50000 K - are found to be efficient in ionizing their surroundings. Observational effects on the 21 cm brightness temperature, the thermal and kinetic Sunyaev-Ze'ldovich effects, are also studied in the context of the upcoming radio and microwave telescopes like LOFAR and SPT.Comment: 19 pages, 24 figures, accepted to be published in MNRAS Typos in formula 1,2 and 21 fixed. Figure 11 caption and Figure 13 change

Detection and extraction of signals from the epoch of reionization using higher-order one-point statistics

Detecting redshifted 21-cm emission from neutral hydrogen in the early Universe promises to give direct constraints on the epoch of reionization (EoR). It will, though, be very challenging to extract the cosmological signal (CS) from foregrounds and noise which are orders of magnitude larger. Fortunately, the signal has some characteristics which differentiate it from the foregrounds and noise, and we suggest that using the correct statistics may tease out signatures of reionization. We generate mock data cubes simulating the output of the Low Frequency Array (LOFAR) EoR experiment. These cubes combine realistic models for Galactic and extragalactic foregrounds and the noise with three different simulations of the CS. We fit out the foregrounds, which are smooth in the frequency direction, to produce residual images in each frequency band. We denoise these images and study the skewness of the one-point distribution in the images as a function of frequency. We find that, under sufficiently optimistic assumptions, we can recover the main features of the redshift evolution of the skewness in the 21-cm signal. We argue that some of these features ¿ such as a dip at the onset of reionization, followed by a rise towards its later stages ¿ may be generic, and give us a promising route to a statistical detection of reionization

Mapping local patterns of childhood overweight and wasting in low- and middle-income countries between 2000 and 2017

A double burden of malnutrition occurs when individuals, household members or communities experience both undernutrition and overweight. Here, we show geospatial estimates of overweight and wasting prevalence among children under 5 years of age in 105 low- and middle-income countries (LMICs) from 2000 to 2017 and aggregate these to policy-relevant administrative units. Wasting decreased overall across LMICs between 2000 and 2017, from 8.4% (62.3 (55.1–70.8) million) to 6.4% (58.3 (47.6–70.7) million), but is predicted to remain above the World Health Organization’s Global Nutrition Target of <5% in over half of LMICs by 2025. Prevalence of overweight increased from 5.2% (30 (22.8–38.5) million) in 2000 to 6.0% (55.5 (44.8–67.9) million) children aged under 5 years in 2017. Areas most affected by double burden of malnutrition were located in Indonesia, Thailand, southeastern China, Botswana, Cameroon and central Nigeria. Our estimates provide a new perspective to researchers, policy makers and public health agencies in their efforts to address this global childhood syndemic

Medical renal disease in tumor nephrectomies: The silent killer

In tumor nephrectomy specimens, the evaluation of the normal renal parenchyma is often overlooked. A patient with both end-stage renal diseases (ESRDs) with a renal cell carcinoma is more likely to die of the ESRD rather than cancer. At the time of nephrectomy, a pathologist has a large amount of tissue available to him to comment upon the presence of disease in the nonneoplastic kidney. Hence, this study was undertaken with the idea of characterizing disease in the nonneoplastic kidney at the time of tumor nephrectomy. A two-year retrospective study was carried out on all tumor nephrectomies and partial nephrectomies. Glomerular, tubulointerstitial, and vascular compartments were evaluated for abnormalities. Twenty-four cases were included in the study. A total of 17 cases showed abnormalities in the nonneoplastic renal parenchyma. In the glomeruli, two cases showed IgA nephropathy, one case showed segmental sclerosis, and one case showed the presence of cellular crescents. A single case showed diabetic glomerulosclerosis. Interstitial fibrosis and tubular atrophy were noted in seven cases. Fifteen cases showed intimal sclerosis and medial hypertrophy and six cases showed nodular hyalinosis. Tumor nephrectomy specimens may very often show the presence of various nonneoplastic diseases. Hypertensive and diabetic renal disease are the major contributors, although primary glomerular diseases may also be present. At the time of the evaluation of a renal tumor on nephrectomy specimen, the status of the nonneoplastic kidney may become as an important predictor of clinical outcome as the tumor itself

Single-center experience of slow thrombolysis in stuck mechanical mitral valve in India

Introduction: India is the rheumatic heart disease (RHD) capital of the world. It is home to 40% of all people of RHD. Many of these patients undergo valve replacement surgeries in our country. These patients present with prosthetic heart valve thrombosis (PHVT) as the international normalized ratio (INR) is not monitored due to several restraints. Many precious lives are lost due to the scarcity of cardiac surgery centers and the high mortality associated with redo procedures. Various international studies have proved the efficacy and low complication rate of slow thrombolysis with tissue plasminogen activator (tPA) compared to surgery in PHVT. Most Indian studies have used streptokinase for PHVT and data on tPA are lacking. Materials and Methods: Twenty-one patients with prosthetic mechanical mitral valve presenting with dyspnea, a high gradient across the prosthetic valve, and decreased leaflet motion were included in the study. As it is not always possible to differentiate pannus from a thrombus and association of some degree of thrombosis even in pannus, we offered thrombolysis as the first line of treatment to all patients. Slow thrombolysis with 25 mg of tPA over 6 h followed by unfractionated heparin for 18 h was given, and thereafter, patients were reassessed for thrombolytic success or complications if any. A total four sessions of thrombolysis were given, and thereafter, patients with failed thrombolysis were referred for valve replacement surgery. Results: Out of 21 patients, 67% were females. The mean age of patients was 54.33 ± 10.6 years. Fifty-seven percent of patients were in the New York Heart Association (NYHA) III/IV. Atrial fibrillation was present in 62% of patients. The mean time of interval from the time of valve surgery to the time of thrombosis was 80 ± 57 months and the mean INR was 1.43 ± 0.4. The total success rate was 71% in this study, 9% had complications, and 19% had failed thrombolysis and underwent redo mitral valve replacement. The mean dose of tPA was 56.58 mg in this study and a mortality rate of 4%. Age had no effect on the success of thrombolysis. The presence of sinus rhythm, NYHA class I/II status, EF more than 40%, and mean gradient <20 mmHg was associated with a higher likelihood of success. Conclusion: In this study of PHVT in Indian patients, slow (6 h) infusion of low-dose (25 mg) tPA proves to be associated with a low complication rate, low mortality, and a promising success rate. This regimen can be offered to PHVT patients in our peripheral centers where cardiac surgical facilities are not readily available

Transcatheter aortic valve implantation using coplanar and cuspal overlap techniques in Indian patients

Introduction: Transcatheter Aortic Valve Implantation (TAVI) techniques gradually evolved since 2002 and have undergone various refinements. Achieving optimal implantation depth has become crucial for good long term outcome. High implantation decreases the likelihood of conduction disturbances. Conventionally TAVI valve is positioned in a tricusp coplanar (CON) fluoroscopic projection however it does not ensure a optimal implantation. In an attempt to attain higher implantation(3 mm) and decrease rate of permanent pacemaker, cuspal overlap technique (COT) view has been developed. There is scarcity of Indian literature comparing TAVI deployment using coplanar and cuspal overlap techniques. Methods: We included 111 patients who underwent TAVR with a self-expanding Core Valve Evolut R (Medtronic, Minneapolis, Minnesota), between January 2017 to September 2022 at our centre.Transcatheter Heart Valves (THV) were implanted using the traditional coplanar in 55 patients, while in 56 patients valves were implanted using the COT. Results: Baseline characteristics including electrocardiographic findings were comparable in both groups. In all patients Evolut R or Evolut PRO valves were used. Procedure was done in conscious sedation in 90.9 % of patients in CON and 96.4 % in COT group. Predilatation and postdilatation was used in 38.8 % vs 33.9 % and 27 % vs 32 % in CON and COT groups respectively. 90 day PPI rate was less in COT group (7.3 % CON vs 3.5 % COP). Majority of patients who received permanent pacemaker implantation (PPI) had baseline ECG abnormality (RBBB in 50 %, LBBB in 16 %, Grade 1 AV block 16 %). Mean time of post procedure PPI was 5.6 days in COT group and 7.3 days in CON group. New onset LBBB was also less in COT group (21 % CON vs 12.5 % COT).There were 3.6 % intraprocedural deaths in CON group and 1.8 % in COT group. Depth of deployed valve was 4.8 ± 2.34 mm in COT and 6.6 ± 2.11 mm in CON group. Valve deployment time was more in COT group(10.40 CON vs 14.34 min COT). Average valve recapture rate was 2.58 in COP and 2.11 in CON. Stroke rate was more in COT group(3.6 % CON vs 7.14 % COT). Pericardial effusions were also more in COT group. All cause mortality at 3 months was 10.9 % in CON group and 5.3 % in COT. Conclusion: In this study we achieved lower rates of PPI and new onset LBBB using COT technique in Indian patients using self-expandable prostheses. However valve deployment time, stroke rate and pericardial effusion were seen more in COT group. All cause mortality was low in cuspal overlap technique

Microfluidic glycosyl hydrolase screening for biomass-to-biofuel conversion

The hydrolysis of biomass to fermentable sugars using glycosyl hydrolases such as cellulases and hemicellulases is a limiting and costly step in the conversion of biomass to biofuels. Enhancement in hydrolysis efficiency is necessary and requires improvement in both enzymes and processing strategies. Advances in both areas in turn strongly depend on the progress in developing high-throughput assays to rapidly and quantitatively screen a large number of enzymes and processing conditions. For example, the characterization of various cellodextrins and xylooligomers produced during the time course of saccharification is important in the design of suitable reactors, enzyme cocktail compositions, and biomass pretreatment schemes. We have developed a microfluidic-chip-based assay for rapid and precise characterization of glycans and xylans resulting from biomass hydrolysis. The technique enables multiplexed separation of soluble cellodextrins and xylose oligomers in around 1 min (10-fold faster than HPLC). The microfluidic device was used to elucidate the mode of action of Tm-Cel5A, a novel cellulase from hyperthermophile Thermotoga maritima. The results demonstrate that the cellulase is active at 80 °C and effectively hydrolyzes cellodextrins and ionic-liquid-pretreated switchgrass and Avicel to glucose, cellobiose, and cellotriose. The proposed microscale approach is ideal for quantitative large-scale screening of enzyme libraries for biomass hydrolysis, for development of energy feedstocks, and for polysaccharide sequencing

Efficacy of stem cell in improvement of left ventricular function in acute myocardial infarction - MI3 Trial

Background and objectives: Acute myocardial infarction (AMI) is characterized by irreparable and irreversible loss of cardiac myocytes. Despite major advances in the management of AMI, a large number of patients are left with reduced left ventricular ejection fraction (LVEF), which is a major determinant of short and long term morbidity and mortality. A review of 33 randomized control trials has shown varying improvement in left ventricular (LV) function in patients receiving stem cells compared to standard medical therapy. Most trials had small sample size and were underpowered. This phase III prospective, open labelled, randomized multicenteric trial was undertaken to evaluate the efficacy in improving the LVEF over a period of six months, after injecting a predefined dose of 5-10 Χ 10 [8] autologous mononuclear cells (MNC) by intra-coronary route, in patients, one to three weeks post ST elevation AMI, in addition to the standard medical therapy. Methods: In this phase III prospective, multicentric trial 250 patients with AMI were included and randomized into stem cell therapy (SCT) and non SCT groups. All patients were followed up for six months. Patients with AMI having left ventricular ejection fraction (LVEF) of 20-50 per cent were included and were randomized to receive intracoronary stem cell infusion after successfully completing percutaneous coronary intervention (PCI). Results: On intention-to-treat analysis the infusion of MNCs had no positive impact on LVEF improvement of ≥ 5 per cent. The improvement in LVEF after six months was 5.17 ± 8.90 per cent in non SCT group and 4.82 ± 10.32 per cent in SCT group. The adverse effects were comparable in both the groups. On post hoc analysis it was noted that the cell dose had a positive impact when infused in the dose of ≥ 5 X 10 [8] (n=71). This benefit was noted upto three weeks post AMI. There were 38 trial deviates in the SCT group which was a limitation of the study. Interpretation and conclusions:Infusion of stem cells was found to have no benefit in ST elevation AMI. However, the procedure was safe. A possible benefit was seen when the predefined cell dose was administered which was noted upto three weeks post AMI, but this was not significant and needs confirmation by larger trials

Improved Activity of a Thermophilic Cellulase, Cel5A, from Thermotoga maritima on Ionic Liquid Pretreated Switchgrass

Ionic liquid pretreatment of biomass has been shown to greatly reduce the recalcitrance of lignocellulosic biomass, resulting in improved sugar yields after enzymatic saccharification. However, even under these improved saccharification conditions the cost of enzymes still represents a significant proportion of the total cost of producing sugars and ultimately fuels from lignocellulosic biomass. Much of the high cost of enzymes is due to the low catalytic efficiency and stability of lignocellulolytic enzymes, especially cellulases, under conditions that include high temperatures and the presence of residual pretreatment chemicals, such as acids, organic solvents, bases, or ionic liquids. Improving the efficiency of the saccharification process on ionic liquid pretreated biomass will facilitate reduced enzyme loading and cost. Thermophilic cellulases have been shown to be stable and active in ionic liquids but their activity is typically at lower levels. Cel5A_Tma, a thermophilic endoglucanase from Thermotoga maritima, is highly active on cellulosic substrates and is stable in ionic liquid environments. Here, our motivation was to engineer mutants of Cel5A_Tma with higher activity on 1-ethyl-3-methylimidazolium acetate ([C(2)mim][OAc]) pretreated biomass. We developed a robotic platform to screen a random mutagenesis library of Cel5A_Tma. Twelve mutants with 25–42% improvement in specific activity on carboxymethyl cellulose and up to 30% improvement on ionic-liquid pretreated switchgrass were successfully isolated and characterized from a library of twenty thousand variants. Interestingly, most of the mutations in the improved variants are located distally to the active site on the protein surface and are not directly involved with substrate binding