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The article focuses on observing and documenting a predation event where a frog, identified as Raorchestes nerostagona (Kalpatta Yellow Bush Frog), was caught and consumed by a snake of the genus Dendrelaphis in Kadanoor, Coorg, Karnataka, India.

Tourism is Australia's fourth-largest exporting sector, yet little research has been done on how satisfied guests are with the indoor environmental quality (IEQ) of Australian guest homes. This research project utilized web-mining, natural language processing and sentiment analysis to analyse customers' IEQ satisfaction in Australian tourist accommodations across ten tourism cities. By analysing 543,213 guest reviews from 1,397 hotels and serviced apartments with two-stars and above at the Booking.com, guests' text comments were classified by semi-supervised word-embedding based models into nine IEQ dimensions. Using a bespoke deep sequence model, sentiment polarities were found, and sentiment scores were computed to estimate the degree of IEQ satisfaction. Results showed that guests were most dissatisfied with facilities, cleanliness and maintenance, and acoustics. As the buildings' star ratings increased, dissatisfaction towards thermal environment, indoor air quality (IAQ), and acoustics decreased. Some IEQ dimensions displayed seasonal trends in customer dissatisfaction. The main sources of dissatisfaction with the thermal environment, IAQ, lighting, and acoustics were identified.

Pyridoxal 5'-phosphate (PLP)-dependent enzymes are the most versatile biocatalysts for synthesizing nonproteinogenic amino acids. α,α-Disubstituted quaternary amino acids, such as 1-aminocyclopentane-1-carboxylic acid (cycloleucine), are useful building blocks for pharmaceuticals. In this study, starting with the biosynthesis of fusarilin A, we discovered a family of PLP-dependent enzymes that can facilitate tandem carbon-carbon forming steps to catalyze an overall [3 + 2]-annulation. In the first step, the cycloleucine synthases use SAM as the latent electrophile and an in situ-generated enamine as the nucleophile for γ-substitution. Whereas previously characterized γ-replacement enzymes protonate the resulting α-carbon and release the acyclic amino acid, cycloleucine synthases can catalyze an additional, intramolecular aldol or Mannich reaction with the nucleophilic α-carbon to form the substituted cyclopentane. Overall, the net [3 + 2]-annulation reaction can lead to 2-hydroxy or 2-aminocycloleucine products. These studies further expand the biocatalytic scope of PLP-dependent enzymes.

G-protein coupled receptors (GPCRs) are the most prominent family of membrane proteins that serve as major targets for one-third of the drugs produced. A detailed understanding of the molecular mechanism of drug-induced activation and inhibition of GPCRs is crucial for the rational design of novel therapeutics. The binding of the neurotransmitter adrenaline to the β 2 -adrenergic receptor (β 2 AR) is known to induce a flight or fight cellular response, but much remains to be understood about binding-induced dynamical changes in β 2 AR and adrenaline. In this article, we examine the potential of mean force (PMF) for the unbinding of adrenaline from the orthosteric binding site of β 2 AR and the associated dynamics using umbrella sampling and molecular dynamics (MD) simulations. The calculated PMF reveals a global energy minimum, which corresponds to the crystal structure of β 2 AR-adrenaline complex, and a meta-stable state in which the adrenaline is moved slightly deeper into the binding pocket with a different orientation compared to that in the crystal structure. The orientational and conformational changes in adrenaline during the transition between these two states and the underlying driving forces of this transition are also explored. Based on the clustering of MD configurations and machine learning-based statistical analyses of time series of relevant collective variables, the structures and stabilizing interactions of these two states of the β 2 AR-adrenaline complex are also investigated.

Isonitrile lipopeptides (INLPs) are known to be related to the virulence of pathogenic mycobacteria by mediating metal transport, but their biosynthesis remains obscure. In this work, we use in vitro biochemical assays, site-directed mutagenesis, chemical synthesis, and spectroscopy techniques to scrutinize the activity of core enzymes required for INLP biosynthesis in mycobacteria. Compared to environmental Streptomyces , pathogenic Mycobacterium employ a similar chemical logic and enzymatic machinery in INLP biosynthesis, differing mainly in the fatty-acyl chain length, which is controlled by multiple enzymes in the pathway. Our in-depth study on the non-heme iron(II) and α-ketoglutarate-dependent dioxygenase for isonitrile generation, including Rv0097 from Mycobacterium tuberculosis ( Mtb ), demonstrates that it recognizes a free-standing small molecule substrate, different from the recent hypothesis that a carrier protein is required for Rv0097 in Mtb . A key residue in Rv0097 is further identified to dictate the varied fatty-acyl chain length specificity between Streptomyces and Mycobacterium .

Background: The available evidence was systematically reviewed to evaluate the effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors (SGLT2i) on cardiovascular (CV) and renal outcomes in people with type 2 diabetes mellitus (T2DM) and atherosclerotic cardiovascular disease (ASCVD) or multiple risk factors (MRF), with or without heart failure (HF), and per estimated glomerular filtration rate (eGFR) rate at baseline., Methods: We comprehensively searched three electronic databases to retrieve publications up to 30th November 2019, which were screened for inclusion. The data extracted for the outcomes according to baseline ASCVD, HF, and eGFR levels were meta-analyzed using fixed effects model., Results: Of the 735 screened citations, 15 primary and secondary publications from five CV or renal outcome trials were included. SGLT2is reduced the risk of CV death or hospitalization for HF (HHF), HHF alone, and composite renal-specific outcome, irrespective of ASCVD and HF at baseline. The three-point major adverse cardiovascular events (3P-MACE) risk was reduced by 14% (p<0.001) in patients with ASCVD and by 10% (p = 0.018) in those without baseline HF compared with their counterparts. SGLT2is significantly reduced the risk of MACE (18%) in patients with mild kidney dysfunction (eGFR within the range of 60-<90 mL/min/1.73 m2 and <60 mL/min/1.73 m2 )., Conclusion: SGLT2is are effective for both secondary and primary prevention of composite CV outcomes, and secondary prevention of MACE. The upcoming evidence may strengthen the primary prevention benefits of SGLT2is., (© Journal of the Association of Physicians of India 2011.)

Parental care is widespread and has fitness benefits. But caregiving parents incur costs including higher predation, and this may lead to selection for body colors or patterns that help mitigate the risks of caring. The evolution of coloration, including sexual dichromatism, however, can be driven by other factors, such as sexual selection. Therefore, examining the associations between parental care and color patterns may provide key insights into evolutionary patterns and selection pressures for parental care. Our comparative analysis of 988 anuran species reveals that dichromatic species are less likely to provide parental care, irrespective of the caregiving sex, and are more likely to breed in aquatic habitats. We then examined whether dorsal colors and patterns that enhance crypticity or function as aposematic signals are associated with the caregiving sex, and the modality of care (transport or stationary). Only caregiving males are more likely to have dorsal Stripes, but none of the colors (Green-Brown, Red, Yellow, Blue-Black) and other patterns (Plain, Bands, Spots, Mottled-Patches) were associated with caregiving females or the modality of care. Overall, sexual dichromatism, breeding ecology, and parental care are associated, but the evolution of caregiving behavior does not appear to influence the myriad colors and patterns characteristic of anurans globally., (© 2022 The Authors. Evolution © 2022 The Society for the Study of Evolution.)