97 research outputs found
Comment on the paper "Calorimetric Dark Matter Detection with Galactic Center Gas Clouds"
The paper "Calorimetric Dark Matter Detection with Galactic Center Gas
Clouds" (Bhoonah et al. 2018) aims to derive limits on dark matter interactions
by demanding that heat transfer due to DM interactions is less than that by
astrophysical cooling, using clouds in the hot, high-velocity nuclear outflow
wind of the Milky Way ( K, 330 km/s).
We argue that clouds in such an extreme environment cannot be assumed to be
stable over the long timescales associated with their radiative cooling rates.
Furthermore, Bhoonah et al. (2018) uses incorrect parameters for their clouds.Comment: 2 pages, 1 figure. Version appearing in Phys. Rev. Let
Low temperature deformation behaviour of ASTM A-203D nuclear structural steel
The steel A-203D in martensitic, tempered martensitic and ferritic-pearlitic microstructural conditions, was deformed in tension at temperatures between 77 to 300 K and at a strain rate of 6.67×10-5 sec-1. The thermal component of the flow stress and the activation parameters were measured as a function of temperature. It was observed that the microstructure did not affect either the thermal part of the flow stress (σ*) or the activation parameters (V* and ΔH) and that its effect was felt only on the athermal component (σμ) of the flow stress. Further the relations of the activation parameters with stress, strain and temperature were found to be consistent with Dorn-Rajnak theory of Peierls mechanism of plastic deformation. In addition measurements of slow-bend and impact transition were also carried out for ferritic-pearlitic structure. Based on these observations, it is shown that the impact transition temperature of this structure can be emperically correlated with the thermal activation parameters
Gastroretentive drug delivery system of captopril and hydrochlorothiazide bilayer tablet: formulation, optimization and in vivo evaluation
The purpose of the present study was to develop and optimize floating-bioadhesive bilayer
gastroretentive drug delivery system (GRDDS) exhibiting a unique combination of floatation and bioadhesion
to prolong residence in the stomach using captopril (CP) and hydrochlorothiazide (HCTZ) as a model
drug. Captopril being unstable in intestinal pH and HCTZ has specific absorption from duodenum and
the first part of the jejunum and to a small extent in the stomach are suitable candidate for GRDDS. 32
factorial design was employed in formulating and optimizing the GRDDS for bilayer tablet of CP and
HCTZ matrix tablet. The main effect and interaction terms were quantitatively evaluated using a mathematical
model. The gastroretentive ability of the tablets was evaluated by X-radiographic studies in
healthy human volunteer. The tablet releases CP and HCTZ for extended period up to 24 h in controlled
manner. The predicted values agreed well with the experimental values and the results demonstrate the
feasibility of the optimization methodology in the development of GRDDS. The tablet was buoyant for up
to 16 h in human stomach. Development of once a day gastroretentive formulation of CP and HCTZ improves
the patience compliance and bioavailability of drugs.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Gastroretentive drug delivery system of captopril and hydrochlorothiazide bilayer tablet: formulation, optimization and in vivo evaluation
The purpose of the present study was to develop and optimize floating-bioadhesive bilayer
gastroretentive drug delivery system (GRDDS) exhibiting a unique combination of floatation and bioadhesion
to prolong residence in the stomach using captopril (CP) and hydrochlorothiazide (HCTZ) as a model
drug. Captopril being unstable in intestinal pH and HCTZ has specific absorption from duodenum and
the first part of the jejunum and to a small extent in the stomach are suitable candidate for GRDDS. 32
factorial design was employed in formulating and optimizing the GRDDS for bilayer tablet of CP and
HCTZ matrix tablet. The main effect and interaction terms were quantitatively evaluated using a mathematical
model. The gastroretentive ability of the tablets was evaluated by X-radiographic studies in
healthy human volunteer. The tablet releases CP and HCTZ for extended period up to 24 h in controlled
manner. The predicted values agreed well with the experimental values and the results demonstrate the
feasibility of the optimization methodology in the development of GRDDS. The tablet was buoyant for up
to 16 h in human stomach. Development of once a day gastroretentive formulation of CP and HCTZ improves
the patience compliance and bioavailability of drugs.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Growth and characterization of heteroepitaxial La-substituted BaSnO films on SrTiO (001) and SmScO (110) substrates
Heteroepitaxial growth of BaSnO (BSO) and BaLaSnO (x = 7
%) (LBSO) thin films on different perovskite single crystal (SrTiO (001)
and SmScO (110)) substrates has been achieved by Pulsed Laser Deposition
(PLD) under optimized deposition conditions. X-ray diffraction measurements
indicate that the films on either of these substrates are relaxed due to the
large mismatch and present a high degree of crystallinity with narrow rocking
curves and smooth surface morphology while analytical quantification by proton
induced x-ray emission (PIXE) confirms the stoichiometric La transfer from a
polyphasic target, producing films with La contents above the bulk solubility
limit. The films show degenerate semiconducting behavior on both substrates,
with the observed room temperature resistivities, Hall mobilities and carrier
concentrations of 4.4 , 10.11 , and 1.38
on SmScO and 7.8 , 5.8 , and 1.36 on SrTiO ruling out any extrinsic
contribution from the substrate. The superior electrical properties observed on
the SmScO3 substrate are attributed to reduction in dislocation density from
the lower lattice mismatch.Comment: 11 pages, 3 figures, supplementary informations 2 figure
History of Premenstrual Mood Change and Postpartum Episodes are Associated with Perimenopausal Episodes in Women with Bipolar Disorder
Background and Aims: Reproductive life events are potential triggers of mood episodes in women with bipolar disorder. We aimed to establish whether a history of premenstrual mood change and postpartum episodes are associated with perimenopausal episodes in women who have bipolar disorder.
Methods: Participants were 339 post-menopausal women with DSM-IV bipolar disorder recruited into the Bipolar Disorder Research Network (www.bdrn.org). Women self-reported presence (N = 200) or absence (N = 139) of an illness episode during the perimenopausal period. History of premenstrual mood change was measured using the self-report Premenstrual Symptoms Screening Tool (PSST), and history of postpartum episodes was measured via semi-structured interview (Schedules for Clinical Assessment in Neuropsychiatry, SCAN) and inspection of case-notes.
Results: History of a postpartum episode within 6 months of delivery (OR = 2.13, p = 0.03) and history of moderate/severe premenstrual syndrome (OR = 6.33, p < 0.001) were significant predictors of the presence of a perimenopausal episode, even after controlling for demographic factors. When we narrowed the definition of premenstrual mood change to premenstrual dysphoric disorder, it remained significant (OR = 2.68, p = 0.007).
Conclusions: Some women who have bipolar disorder may be particularly sensitive to reproductive life events. Previous mood episodes in relation to the female reproductive lifecycle may help clinicians predict individual risk for women with bipolar disorder approaching the menopause. There is a need for prospective longitudinal studies of women with bipolar disorder providing frequent contemporaneous ratings of their mood to overcome the limitations of retrospective self-report data
The SZ flux-mass (-) relation at low halo masses: improvements with symbolic regression and strong constraints on baryonic feedback
Feedback from active galactic nuclei (AGN) and supernovae can affect
measurements of integrated SZ flux of halos () from CMB surveys,
and cause its relation with the halo mass () to deviate from
the self-similar power-law prediction of the virial theorem. We perform a
comprehensive study of such deviations using CAMELS, a suite of hydrodynamic
simulations with extensive variations in feedback prescriptions. We use a
combination of two machine learning tools (random forest and symbolic
regression) to search for analogues of the relation which are more robust
to feedback processes for low masses ();
we find that simply replacing in the
relation makes it remarkably self-similar. This could serve as a robust
multiwavelength mass proxy for low-mass clusters and galaxy groups. Our
methodology can also be generally useful to improve the domain of validity of
other astrophysical scaling relations.
We also forecast that measurements of the relation could provide
percent-level constraints on certain combinations of feedback parameters and/or
rule out a major part of the parameter space of supernova and AGN feedback
models used in current state-of-the-art hydrodynamic simulations. Our results
can be useful for using upcoming SZ surveys (e.g., SO, CMB-S4) and galaxy
surveys (e.g., DESI and Rubin) to constrain the nature of baryonic feedback.
Finally, we find that the an alternative relation, , provides
complementary information on feedback than Comment: Version appearing in MNRAS. Minor change to Fig.6 and added Fig. A5
compared to the previous version. 7+5 pages. The code and data associated
with this paper are available at
https://github.com/JayWadekar/ScalingRelations_M
Ileo-cecal targeting mucoadhesive budesonide tablet
Crohn's disease occurs at any part of gastro-intestinal tract (GIT) but the most susceptible is
the ileo-cecal region. For an effective treatment of this disease is essential the drug to be released at ileo-cecal
region for an extended period of time. The present study is an attempt to design and develop an ileo-cecal
targeting mucoadhesive drug delivery system that may be released specifically and slowly in ileo-cecal
region without being released in the upper GIT for an extended period of time (12 h). Budesonide mucoadhesive
tablets are coated with Eudragit S100, which is a polymer that specifically dissolves at and above
pH 6.8. The in vitro drug release by changing pH method was done and in vivo study using X-ray radiography
was carried out to ascertain the position of tablets in GIT after specific time intervals. The in vitro
performance of the tablet with 10 % w/w coating level showed that the tablet did not disintegrate till 16 h
with constant drug release. An in vivo study also reveals that the tablet lasted till 16 h in the ileo-cecal region.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Gastroretentive drug delivery system of captopril and hydrochlorothiazide bilayer tablet: formulation, optimization and in vivo evaluation
The purpose of the present study was to develop and optimize floating-bioadhesive bilayer
gastroretentive drug delivery system (GRDDS) exhibiting a unique combination of floatation and bioadhesion
to prolong residence in the stomach using captopril (CP) and hydrochlorothiazide (HCTZ) as a model
drug. Captopril being unstable in intestinal pH and HCTZ has specific absorption from duodenum and
the first part of the jejunum and to a small extent in the stomach are suitable candidate for GRDDS. 32
factorial design was employed in formulating and optimizing the GRDDS for bilayer tablet of CP and
HCTZ matrix tablet. The main effect and interaction terms were quantitatively evaluated using a mathematical
model. The gastroretentive ability of the tablets was evaluated by X-radiographic studies in
healthy human volunteer. The tablet releases CP and HCTZ for extended period up to 24 h in controlled
manner. The predicted values agreed well with the experimental values and the results demonstrate the
feasibility of the optimization methodology in the development of GRDDS. The tablet was buoyant for up
to 16 h in human stomach. Development of once a day gastroretentive formulation of CP and HCTZ improves
the patience compliance and bioavailability of drugs.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Two Tetranucleotide Repeats within the Xq21.3/Yp11.2 Human Specific Region of Homology and Their Conservation in Primate Evolution
We locate two tetranucleotide repeat sequences (AT3 and T2C2) between the markers sY44 and sY46 within the Xq21.3/Yp block of homology that has been created since the separation of the chimpanzee and human lineages, and trace their origin in primate evolution. The T2C2 repeat is present only in hominoid primates. The sequence AT3 is present in Old World monkeys but not in New World monkeys, and has been lost in some gibbon species. In the bonobo, the AT3 repeat is the site of a new Alu insertion. These findings and their relationship to the conservation of other markers in this region cast light on the structure of a genomic region that has been subject to change in the course of primate evolution and may include one or more sites of instability
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