82 research outputs found
Socio-economic factors influencing milk donation in milk banks in India: an institutional study
Background: Exclusive breast-feeding has irrefutably been established as the best form of nourishment for neonatal and early infantile age groups. The aim of this study was to retrospectively analyze the socio-economic factors in a developing country like India, which influence maternal motivation and willingness to donate breast milk and to make policy changes to promote the same.Methods: Ours is a retrospective study carried out over a period of 1 year in Cama and Albless hospital in Mumbai. The 948 women donating breast milk in the year 2013, were retrospectively assessed for their socioeconomic parameters such as age, parity, family income, religion & education. The results were further tabulated and assessed.Results: Milk donation was least in the extremes of the reproductive age group. Parity showed an inverse relationship with milk donation. Per capita income and religion did not influence milk donation. Education showed a linear relationship with milk donation, but the milk donation even in the uneducated group of women remained significantly higher than their western counterparts.Conclusions: Women in extremes of age in the reproductive age group and women with higher parity require more motivation to donate breast milk. In our study, milk donation is independent of per capita income and which religion a person belongs to. Milk donation can be promoted by increasing women education in India. However even uneducated women can be motivated to donated breast milk, If the importance of breast feeding is taught to the woman at a young age, & the practice of breast feeding is inculcated into the social culture of the place
Fast-transient Searches in Real Time with ZTFReST: Identification of Three Optically-discovered Gamma-ray Burst Afterglows and New Constraints on the Kilonova Rate
While optical surveys regularly discover slow transients like supernovae on their own, the most common way to discover extragalactic fast transients, fading away in a few nights, is via follow-up observations of gamma-ray burst and gravitational-wave triggers. However, wide-field surveys have the potential to also identify rapidly fading transients independently of such external triggers. The volumetric survey speed of the Zwicky Transient Facility (ZTF) makes it sensitive to faint and fast-fading objects as kilonovae, the optical counterparts to binary neutron stars and neutron star-black hole mergers, out to almost 200Mpc. We introduce an open-source software infrastructure, the ZTF REaltime Search and Triggering, ZTFReST, designed to identify kilonovae and fast optical transients in ZTF data. Using the ZTF alert stream combined with forced photometry, we have implemented automated candidate ranking based on their photometric evolution and fitting to kilonova models. Automated triggering of follow-up systems, such as Las Cumbres Observatory, has also been implemented. In 13 months of science validation, we found several extragalactic fast transients independent of any external trigger (though some counterparts were identified later), including at least one supernova with post-shock cooling emission, two known afterglows with an associated gamma-ray burst, two known afterglows without any known gamma-ray counterpart, and three new fast-declining sources (ZTF20abtxwfx, ZTF20acozryr, and ZTF21aagwbjr) that are likely associated with GRB200817A, GRB201103B, and GRB210204A. However, we have not found any objects which appear to be kilonovae; therefore, we constrain the rate of GW170817-like kilonovae to Gpcyr. A framework such as ZTFReST could become a prime tool for kilonova and fast transient discovery with the Vera C. Rubin Observatory
Synthesis of macrocyclic receptors with intrinsic fluorescence featuring quinizarin moieties
An unprecedented class of macrocycles with intrinsic fluorescence consisting of phenolic trimers and quinizarin is developed. Though they are lacking strong hydrogen bonds as observed in calixarenes, the two examples introduced here each adopt a vase-like conformation with all four aromatic units pointing in one direction (syn orientation). This “cone” conformation has been confirmed by NMR spectroscopy, molecular modeling, and X-ray crystallography. The laminar, electron-rich fluorophore as part of the macrocycle allows additional contacts to enclosed guest molecules
The long-active afterglow of GRB 210204A: detection of the most delayed flares in a gamma-ray burst
We present results from extensive broadband follow-up of GRB 210204A over the period of 30 d. We detect optical flares in the afterglow at 7.6 × 105 s and 1.1 × 106 s after the burst: the most delayed flaring ever detected in a GRB afterglow. At the source redshift of 0.876, the rest-frame delay is 5.8 × 105 s (6.71 d). We investigate possible causes for this flaring and conclude that the most likely cause is a refreshed shock in the jet. The prompt emission of the GRB is within the range of typical long bursts: it shows three disjoint emission episodes, which all follow the typical GRB correlations. This suggests that GRB 210204A might not have any special properties that caused late-time flaring, and the lack of such detections for other afterglows might be resulting from the paucity of late-time observations. Systematic late-time follow-up of a larger sample of GRBs can shed more light on such afterglow behaviour. Further analysis of the GRB 210204A shows that the late-time bump in the light curve is highly unlikely due to underlying SNe at redshift (z) = 0.876 and is more likely due to the late-time flaring activity. The cause of this variability is not clearly quantifiable due to the lack of multiband data at late-time constraints by bad weather conditions. The flare of GRB 210204A is the latest flare detected to date
Integrity of SRP RNA is ensured by La and the nuclear RNA quality control machinery
The RNA component of signal recognition particle (SRP) is transcribed by RNA polymerase III, and most steps in SRP biogenesis occur in the nucleolus. Here, we examine processing and quality control of the yeast SRP RNA (scR1). In common with other pol III transcripts, scR1 terminates in a U-tract, and ma-ture scR1 retains a U4–5 sequence at its 3 ′ end. In cells lacking the exonuclease Rex1, scR1 terminates in a longer U5–6 tail that presumably represents the primary transcript. The 3 ′ U-tract of scR1 is protected from aberrant processing by the La homologue, Lhp1 and overexpressed Lhp1 apparently competes with both the RNA surveillance system and SRP assem-bly factors. Unexpectedly, the TRAMP and exosome nuclear RNA surveillance complexes are also impli-cated in protecting the 3 ′ end of scR1, which accu-mulates in the nucleolus of cells lacking the activities of these complexes. Misassembled scR1 has a pri-mary degradation pathway in which Rrp6 acts early, followed by TRAMP-stimulated exonuclease degra-dation by the exosome. We conclude that the RNA surveillance machinery has key roles in both SRP biogenesis and quality control of the RNA, poten-tially facilitating the decision between these alterna-tive fates
Design and synthesis of oligoamide-based double a-helix mimetics
An extensive series of bis-oligobenzamides and bis-oligopyridylamides have been efficiently prepared and studied by X-ray analysis and computational methods. A modular synthesis led to double ?-helix mimics bearing between two and ten branched side-chains. The inter-helix angle and distance can be tuned by varying the length and rigidity of the spacer, thereby reproducing the recognition domains of a range of super-secondary structures
Design and synthesis of oligoamide-based double a-helix mimetics (Eur. J. Org. Chem. 17/2013)
The cover picture shows the binding of transcription factors to nucleic acids. Top left: multicomponent protein; bottom right: leucine zipper; centre: bis-oligobenzamide peptidomimetic; background: DNA chains. The xanthene-linked bis-oligobenzamide shown in the centre is an example of a super-secondary structural protein mimic. This work details the synthesis of oligobenzamide and oligopyridylamide strands connected through various spacers, allowing tuning of the inter-helix angle and thus the potential nucleic acid or protein binding properties. Details are discussed in the article by A. D. Hamilton et al. on page 3427 ff
Amphiphilic oligoamide a-helix peptidomimetics inhibit islet amyloid polypeptide aggregation
The abnormal deposition of proteins as insoluble plaques is associated with many diseases, including Alzheimer’s, Parkinson’s and type II diabetes. There is an unmet need for synthetic agents that are able to mediate particular steps in the pathway between soluble proteins in their native unfolded state and their insoluble ?-sheet rich aggregates. We have previously reported classes of ?-helix mimetic that agonize or antagonize islet amyloid polypeptide aggregation, depending on the presence of a lipid bilayer. Here we investigate a novel mixed benzamide and pyridylamide scaffold that gives improved activity and explores the role of side-chain polarity, backbone rigidity and curvature in inhibiting lipid-catalyzed fibrillization
Design and Synthesis of Oligoamide-Based Double α-Helix Mimetics
An extensive series of bis-oligobenzamides and bis-oligopyridylamides have been efficiently prepared and studied by X-ray analysis and computational methods. A modular synthesis led to double -helix mimics bearing between two and ten branched side-chains. The inter-helix angle and distance can be tuned by varying the length and rigidity of the spacer, thereby reproducing the recognition domains of a range of super-secondary structures
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