The scarcity of donor organs may be addressed in the future by using pigs to grow humanized organs with lower potential for immunological rejection after transplantation in humans. Previous studies ...have demonstrated that interspecies complementation of rodent blastocysts lacking a developmental regulatory gene can generate xenogeneic pancreas and kidney
. However, such organs contain host endothelium, a source of immune rejection. We used gene editing and somatic cell nuclear transfer to engineer porcine embryos deficient in ETV2, a master regulator of hematoendothelial lineages
. ETV2-null pig embryos lacked hematoendothelial lineages and were embryonic lethal. Blastocyst complementation with wild-type porcine blastomeres generated viable chimeric embryos whose hematoendothelial cells were entirely donor-derived. ETV2-null blastocysts were injected with human induced pluripotent stem cells (hiPSCs) or hiPSCs overexpressing the antiapoptotic factor BCL2, transferred to synchronized gilts and analyzed between embryonic day 17 and embryonic day 18. In these embryos, all endothelial cells were of human origin.
Specific recognition of CN− in sodium cyanide solution was achieved using two imidazole-based receptors (A and B). Visually detectable color changes were associated with the formation of hydrogen ...bonded adducts, A·CN − and B·CN − . Ratiometric fluorescence response was achieved for receptor A on binding to CN−, and this reagent was used for imaging bacterial cells pre-exposed to 1.42 μM CN− solution.
In a sensor cloud system, the sensors collect data and send it to the cloud system so that the end-users can access the data. When the frequency of data transmission is high, more power is consumed ...which reduces the finite battery lifetime of sensors. To reduce the data transmission between sensor and cloud without compromising the frequency of availability of data to end-users, an efficient hybrid forecasting method is developed to forecast the sensor data within the cloud and the end-users get the forecasted data at the same frequency with minimal error. In the proposed hybrid method, the sensor data is first modeled using the support vector machine (SVM) with Gaussian kernel function (SVMG) and SVM with linear kernel function (SVML). The forecasted values of SVMG and SVML are modeled using the artificial neural network to get the true forecasts. To assess the effectiveness of the proposed method, hourly temperature sensor data of Delhi is considered, and the obtained results are compared with the state-of-the-art deep learning, machine learning, ensemble, naïve and hybrid models. In the proposed approach, the sensor communicates with the cloud either every two hours (in case of one-step-ahead forecasting) or six hours (in case of five-step-ahead forecasting), but the user gets the forecasted hourly data from the cloud. Using the proposed approach, the energy consumption is reduced by 50% and 83.56% in comparison to the traditional approach in 1-step-ahead and 5-step-ahead forecasting without compromising much in accuracy.
The vasculature is an essential organ for the delivery of blood and oxygen to all tissues of the body and is thus relevant to the treatment of ischaemic diseases, injury-induced regeneration and ...solid tumour growth. Previously, we demonstrated that ETV2 is an essential transcription factor for the development of cardiac, endothelial and haematopoietic lineages. Here we report that ETV2 functions as a pioneer factor that relaxes closed chromatin and regulates endothelial development. By comparing engineered embryonic stem cell differentiation and reprogramming models with multi-omics techniques, we demonstrated that ETV2 was able to bind nucleosomal DNA and recruit BRG1. BRG1 recruitment remodelled chromatin around endothelial genes and helped to maintain an open configuration, resulting in increased H3K27ac deposition. Collectively, these results will serve as a platform for the development of therapeutic initiatives directed towards cardiovascular diseases and solid tumours.
The abrasive wear response of Al-7.5Si–SiC composite produced by stir casting technique was examined and compared to Al-7.5Si alloy (matrix alloy) and Al-17.5Si (low-cost hypereutectic) alloy in ...as-cast and after heat treatment. The microstructure of the hypereutectic alloy shows the α-Al, α-Si, and Al-Si eutectic phases, and the microstructure of the composite shows the homogeneous dispersion of SiCp in the matrix and excellent bonding of the Al-SiC interface. The wear examinations were performed on pin-on-disc apparatus at 38–80 µm abrasive (grit) sizes, 5–20 N applied loads, 100–400 m sliding (abrading) distances, and 1 m/s constant sliding speed. At 80 µm size of abrasive and 20 N of the applied load, the decrement in wear rate of LM30 alloy and LM25-SiCp composite was 31.82% and 95.37%, respectively, in case of the as-cast condition. However, for heat-treated conditions, the decrement in wear rate of hypereutectic alloy and composite was 32.63% and 96.61%, respectively. The wear rate of specimens was increased with abrasive size and applied load. The wear resistance of the hypereutectic alloy was superior to the matrix alloy but inferior to the composite irrespective of the abrasive size and applied load. The wear surface of the specimens, abrasive papers, and wear debris were analysed by the field-emission scanning electron microscope (FESEM) for the wear mechanism.
The mammalian heart has a limited regenerative capacity and typically progresses to heart failure following injury. Here, we defined a hedgehog (HH)-Gli1-Mycn network for cardiomyocyte proliferation ...and heart regeneration from amphibians to mammals. Using a genome-wide screen, we verified that HH signaling was essential for heart regeneration in the injured newt. Next, pharmacological and genetic loss- and gain-of-function of HH signaling demonstrated the essential requirement for HH signaling in the neonatal, adolescent, and adult mouse heart regeneration, and in the proliferation of hiPSC-derived cardiomyocytes. Fate-mapping and molecular biological studies revealed that HH signaling, via a HH-Gli1-Mycn network, contributed to heart regeneration by inducing proliferation of pre-existing cardiomyocytes and not by de novo cardiomyogenesis. Further, Mycn mRNA transfection experiments recapitulated the effects of HH signaling and promoted adult cardiomyocyte proliferation. These studies defined an evolutionarily conserved function of HH signaling that may serve as a platform for human regenerative therapies.
The rapidly emerging wireless service requirements and deployment demands over last few decades necessitates the application of Mobile Ad hoc Networks in many areas. These application areas vary from ...social networks to safety-critical domains such as environmental monitoring, disaster rescue operations, military communications, etc. The potency of the ad hoc network deployment in a specific context is significantly affected by the underlying routing protocol. Hence, developing an efficient and secure routing protocol for MANETs is an important task in order to achieve the service level requirements and to satisfy the deployment demands effectively. However, development of such routing protocol is a challenging problem due to the inherent characteristics of ad hoc networks: frequent topology changes, open wireless medium, and limited resource constraints, etc. In addition, the stringent requirements: mobility, performance, security, trust and timing constraints, etc. add complexity to this problem. In this paper, we present an adaptive routing protocol for MANETs, which dynamically configures the routing function with respect to the metrics: (1) the varying requirement parameters and (2) the contextual features as per the desired application context. The requirement models include various performance, security, and functional parameters. On the other hand, the contextual features include mobility of nodes/groups of nodes, nodes’ trust values, resource constraints of nodes, geographical context, roles of individual nodes etc. Our routing protocol is evaluated with extensive simulation test cases and the efficacy of the protocol is reported.
Chemical weathering in the Himalayan river basins plays a key role in the global carbon cycle that controls the climate. In this contribution, the spatial distribution of dissolved major ions and ...(inorganic) carbon isotopic compositions of the Teesta River, a major tributary of the Brahmaputra River, has been investigated to constrain solute sources, weathering patterns, and acids involved in these processes. Mixing diagrams and piper plots of major ions indicate a dominant solutes supply by weathering of silicates and carbonates. The average sulfate concentration of the Teesta samples (92 ± 47 µM) is significantly higher than that reported earlier for atmospheric deposition (∼5 µM) in this basin. The carbon isotopic compositions of the dissolved inorganic fractions (δ13CDIC) of the samples vary between −11.87‰ and −3.82‰ (mean: −7‰ ± 2‰). Comparison of δ13CDIC – SO4/(SO4 + HCO3) – HCO3/(Ca + Mg) trends with their corresponding values expected for H2SO4 and H2CO3 acid‐mediated weathering indicates that both these acids contribute to chemical weathering in the Teesta river catchment. Inversion modeling of major ions and δ13CDIC data have been used to quantify the impact of carbonic (H2CO3) and sulfuric acids (H2SO4) on the Teesta water chemistry. On average, the fractions of cations derived from H2CO3‐mediated weathering of carbonates (0.27 ± 0.14) and silicates (0.20 ± 0.09) are comparable with H2SO4‐mediated carbonate (0.38 ± 0.18) and silicate (0.15 ± 0.11) weathering in this basin. These results show that the amount of CO2 uptake (via H2CO3‐mediated silicate weathering) and release (via H2SO4‐mediated carbonate weathering) are in balance for the Teesta River.
Key Points
Sulfate concentrations of the Teesta are higher than that of regional rainwater
About half of the cations are supplied through H2SO4‐mediated weathering
At outflow, the CO2 uptake (silicate weathering) and release (H2SO4‐carbonate weathering) rates are in balance
The increasing human population and rapid development along the east coast of India pose potential threats to coastal water quality. To assess the water quality of two tropical estuaries of Odisha, ...India, diurnal and seasonal variations along with the influence of differential anthropogenic impacts have been studied. From the results, it was evident, the seasonal variations in the water quality were largely influenced by anthropogenic sources at both the estuaries. Relatively lower seasonal variations in salinity were recorded in Mahanadi compared to Dhamara. Dissolved inorganic nitrogen (DIN) concentrations were found to be higher in the Dhamara estuary when compared to the Mahanadi estuary that can be attributed to decay of organic materials followed by the nitrification process. A reverse trend was recorded for dissolved inorganic phosphate (DIP), with significantly higher values recorded in Mahanadi. The partial pressure of carbon dioxide (pCO2) showed strong temporal variations in both the estuaries dominated by moderate CO2 supersaturation with respect to the atmosphere. The mean annual pCO2 was higher in the Mahanadi estuary and was largely attributed to its significant increase during the post-monsoon season. This study indicated the stronger influence of freshwater input and tidal activities compared to that of in situ biological processes in regulating the temporal variations in water quality of both the estuaries. The present study is helpful in understanding the natural state of the estuarine water and protection of ecosystems resources to fulfil the sustainable development at the regional level.
•Mahanadi and Dhamara are two meso-tidal estuaries along the Odisha coast of India.•Surface water quality was monitored diurnally for three seasons.•The influence of freshwater mixing was more in Mahanadi compared to the Dhamara.•Higher DIP in Mahanadi due to the discharge of effluents from fertilizer plants.•Freshwater mixing regulated surface pCO2 higher than biological activities.
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