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In this study, the ion composition of flux transfer events (FTEs) observed within the magnetosheath proper is examined. These FTEs were observed just upstream of the Earth's postnoon magnetopause by the National Aeronautics and Space Administration (NASA) Magnetospheric Multiscale (MMS) spacecraft constellation. The minor ion characteristics are described using energy spectrograms, flux distributions, and ion moments as the constellation encountered each FTE. In conjunction with electron data and magnetic field observations, such observations provide important contextual information on the formation, topologies, and evolution of FTEs. In particular, minor ions, when combined with the field-aligned streaming of electrons, are reliable indicators of FTE topology. The observations are also placed (i) in context of the solar wind magnetic field configuration, (ii) the connection of the sampled flux tube to the ionosphere, and (iii) the location relative to the modeled reconnection line at the magnetopause. While protons and alpha particles were often depleted within the FTEs relative to the surrounding magnetosheath plasma, the He+ and O+ populations showed clear enhancements either near the center or near the edges of the FTE, and the bulk plasma flow directions are consistent with magnetic reconnection northward of the spacecraft and convection from the dayside toward the flank magnetopause.

Pigeon pea (Cajanus cajan) is widely cultivated for its nutritional and medicinal value yet remains an orphan crop as productivity has not been improved because of a lack of genome and non‐coding genome information. Non‐coding RNAs, like miRNAs and long non‐coding RNAs (lncRNAs), are involved in regulation of growth, metabolism, development, and stress response, and have a critical role in post‐transcriptional gene regulation (PTGR).We attempted to elucidate the roles of miRNAs and lncRNAs in pigeon pea through experimental validation of computationally predicted miRNAs and lncRNAs and targets of miRNAs on mRNAs.We experimentally validated 20 miRNAs and 11 lncRNAs. We predicted cleavage sites of three miRNA targets: serine/threonine‐protein kinase, polygalacturonase, beta‐galactosidase. We identified 469 targets of 265 miRNAs and their functional annotations using computational methods. We built a miRNA‐mRNA‐lncRNA network model, with the miRNAs targeting both mRNAs and lncRNAs, to obtain information on the interplay of these three molecules.A confirmed interaction through experimental validation was established between miRNA, namely cca‐miR1535a targeting the mRNA for beta‐galactosidase, as well as the lncRNA cca‐lnc‐020033. Our findings increase knowledge of the non‐coding genome of pigeon pea and their roles in PTGR and in improving agronomic traits of this pulse crop. [ABSTRACT FROM AUTHOR]

Precise computation of evapotranspiration is critical for an efficient irrigation planning and managing agriculture water. This investigation aimed to study the performance of regression techniques and machine learning (ML) techniques in estimating daily reference evapotranspiration (ET0) and compare them to the ET0 computed by the Penman–Monteith (PM-56) technique of "Food and Agriculture Organization" (FAO). The study used the meteorological data of the Pusa Institute, ICAR-IARI, New Delhi, which is located in a semi-arid climatic zone, for a period of 31 years (1990–2020). Six regression techniques were used, including multiple linear regression (MLR), elastic net regression (ENR), ridge regression (RDR), lasso regression (LASSOR), partial least square regression (PLSR), and Poisson regression (POR). Four machine learning models, namely radial basis function (RBF), M5Tree, locally weighted learning (LWL), and gradient boosted tree (GBT), were also evaluated for predicting daily ET0. The M5Tree model outclassed all other models in predicting daily ET0, with a mean absolute error (MAE), mean squared error (MSE), root-mean-squared error (RMSE), R-squared (R2), mean absolute percentage error (MAPE), and Willmott's index (d) of 0.088, 0.018, 0.136, 0.994, 3.073%, and 0.914, respectively, in training of the models. While during testing period, M5Tree model gave MAE, MSE, RMSE, R2, MAPE and d values as 0.114, 0.16, 0.382, 0.949, 3.946% and 0.988, respectively. During training phase, the GBT model reported MAE, MSE, RMSE, R2, MAPE and d as 0.097, 0.021, 0.145, 0.993, 3.257% and 0.998, respectively, which were slightly poor than the M5Tree model. Further, the GBT model showed the best performance during model testing, with MAE, MSE, RMSE, R2, MAPE, and d of 0.126, 0.053, 0.230, 0.982, 4.166%, and 0.995, respectively. Additionally, the POR model performed the worst in predicting daily ET0 values, as evidenced by the prediction error statistics. In conclusion, the developed ET0 model may be utilized to precisely predict ET0 in semi-arid region for efficient irrigation scheduling, especially in the absence of weighing type field lysimeter. [ABSTRACT FROM AUTHOR]

Temozolomide (TMZ) is a DNA methylating agent used to treat brain cancer. TMZ-induced O6-methylguanine adducts, in the absence of repair by O6-methylguanine DNA methyltransferase (MGMT), mispair during DNA replication and trigger cycles of futile mismatch

Normal tissues express the M1 isoform of pyruvate kinase (PK) that helps generate and funnel pyruvate into the mitochondria for ATP production. Tumors, in contrast, express the less active PKM2 isoform, which limits pyruvate production and spares glycolyti

Nicotine alpha(4)beta(2) receptor subtypes are implicated in the study of Alzheimer's disease, schizophrenia, substance abuse, lung cancer, and other disorders. We report the development and evaluation of a putative antagonist, 5-(3'-fluoropropyl)-3-(2-(S)-pyrrolidinylmethoxy)pyridine (nifrolidine) as a PET agent for nicotine alpha(4)beta(2) receptors. Methods: In vitro binding affinity of nifrolidine was measured in rat brain slices labeled with I-125-iodoepibatidine or I-125-bungaratoxin. Selectivity of binding was measured in the presence of cytisine. F-18 radiolabeling was performed by reacting the tosylate precursor with F-18-fluoride followed by cleprotection. In vitro autoradiographic studies in rat brain slices with 5-(3'-F-18-fluoropropyl)-3-(2-(S)-pyrrolidinylmethoxy)pyridine (F-18-nifrolidine) were read on a phosphor imager. Rats were injected with F-18-nifrolidine (3.7 MBq each), and brain regions were counted at various times (2-120 min). Blocking studies were performed by subcutaneous injection of nicotine (10 mg/kg). A PET study of F-18-nifrolidine (approximately 148 MBq) was performed on an anesthetized rhesus monkey using a high-resolution scanner. Results: In vitro binding affinity of nifrolidine exhibited an inhibition constant of 2.89 nmol/L for the alpha(4)beta(2) sites. Radiosynthesis and high-performance liquid chromatography purifications yielded the product in approximately 20%-40% decay-corrected radiochemical yield to provide 18F-nifrolidine specific activities of approximately 111-185 GBq/mumol. In vitro autoradiography in rat brain slices revealed selective binding of F-18-nifrolidine to the anteroventral thalamic nucleus, ventral posteriomedial thalamus, dorsolateral geniculate, and, to a lesser extent, cortex and striata, which are known to contain alpha(4)beta(2) sites. This specific binding was completely abolished by 300 mumol/L nicotine. Ex vivo rat brain distribution studies indicated selective binding in the thalamus with a maximal thalamus-to-cerebellum ratio of approximately 3. The PET study revealed selective maximal uptake (0.01 % injected dose/mL) in regions of the thalamus (anteroventral and anteromedial mus, ventrolateral thalamus) and extrathalamic regions such as cingulate gyrus, lateral geniculate, temporal cortex, and frontal cortex. Conclusion: Binding of F-18-nifrolidine to alpha(4)beta(2) receptor-rich regions in rats and monkeys indicates promise as a PET agent. Additionally, the thalamus-to-cerebellum ratio approached a plateau of 1.7 in 120 min, indicating relatively faster kinetics compared with previously reported imaging agents.