Object-X: The Brightest Mid-IR Point Source in M33

We discuss the nature of the brightest mid-IR point source (which we dub Object X) in the nearby galaxy M33. Although multi-wavelength data on this object have existed in the literature for some time, it has not previously been recognized as the most luminous mid-IR object in M33 because it is entirely unremarkable in both optical and near-IR light. In the Local Group Galaxies Survey, Object X is a faint red source visible in VRI and H-alpha but not U or B. It was easily seen at JHK_s in the 2MASS survey. It is the brightest point source in all four Spitzer IRAC bands and is also visible in the MIPS 24-micron band. Its bolometric luminosity is 5x10^5 L_sun. The source is optically variable on short time scales (tens of days) and is also slightly variable in the mid-IR, indicating that it is a star. Archival photographic plates (from 1949 and 1991) show no optical source, so the star has been obscured for at least half a century. Its properties are similar to those of the Galactic OH/IR star IRC+10420 which has a complex dusty circumstellar structure resulting from episodic low velocity mass ejections. We propose that Object X is a M>30 M_sun evolved star obscured in its own dust ejected during episodic mass loss events over at least half a century. It may emerge from its current ultra-short evolutionary phase as a hotter post-RSG star analogous to M33 Var A. The existence and rarity of such objects can be an important probe of a very brief yet eventful stellar evolutionary phase.Comment: 20 pages, 10 figures. Accepted for publication by Ap

Census of Self-Obscured Massive Stars in Nearby Galaxies with Spitzer: Implications for Understanding the Progenitors of SN 2008S-Like Transients

A new link in the causal mapping between massive stars and potentially fatal explosive transients opened with the 2008 discovery of the dust-obscured progenitors of the luminous outbursts in NGC 6946 and NGC 300. Here we carry out a systematic mid-IR photometric search for massive, luminous, self-obscured stars in four nearby galaxies: M33, NGC 300, M81, and NGC 6946. For detection, we use only the 3.6 micron and 4.5 micron IRAC bands, as these can still be used for multi-epoch Spitzer surveys of nearby galaxies (=<10 Mpc). We combine familiar PSF and aperture-photometry with an innovative application of image subtraction to catalog the self-obscured massive stars in these galaxies. In particular, we verify that stars analogous to the progenitors of the NGC 6946 (SN 2008S) and NGC 300 transients are truly rare in all four galaxies: their number may be as low as ~1 per galaxy at any given moment. This result empirically supports the idea that the dust-enshrouded phase is a very short-lived phenomenon in the lives of many massive stars and that these objects constitute a natural extension of the AGB sequence. We also provide mid-IR catalogs of sources in NGC 300, M81, and NGC 6946.Comment: 21 pages, 15 figures, 11 tables. Accepted by ApJ on April 12, 2010. High resolution figures and full length versions of tables 6, 8 and 10 can be accessed at http://www.astronomy.ohio-state.edu/~khan/redstars

Effect of temperature anisotropy on various modes and instabilities for a magnetized non-relativistic bi-Maxwellian plasma

Using kinetic theory for homogeneous collisionless magnetized plasmas, we present an extended review of the plasma waves and instabilities and discuss the anisotropic response of generalized relativistic dielectric tensor and Onsager symmetry properties for arbitrary distribution functions. In general, we observe that for such plasmas only those electromagnetic modes whose magnetic field perturbations are perpendicular to the ambient magneticeld, i.e.,B1 \perp B0, are effected by the anisotropy. However, in oblique propagation all modes do show such anisotropic effects. Considering the non-relativistic bi-Maxwellian distribution and studying the relevant components of the general dielectric tensor under appropriate conditions, we derive the dispersion relations for various modes and instabilities. We show that only the electromagnetic R- and L- waves, those derived from them and the O-mode are affected by thermal anisotropies, since they satisfy the required condition B1\perpB0. By contrast, the perpendicularly propagating X-mode and the modes derived from it (the pure transverse X-mode and Bernstein mode) show no such effect. In general, we note that the thermal anisotropy modifies the parallel propagating modes via the parallel acoustic effect, while it modifies the perpendicular propagating modes via the Larmor-radius effect. In oblique propagation for kinetic Alfven waves, the thermal anisotropy affects the kinetic regime more than it affects the inertial regime. The generalized fast mode exhibits two distinct acoustic effects, one in the direction parallel to the ambient magnetic field and the other in the direction perpendicular to it. In the fast-mode instability, the magneto-sonic wave causes suppression of the firehose instability. We discuss all these propagation characteristics and present graphic illustrations

Population genetic portrait of Pakistani Lahore-Christians based on 32 STR loci.

Phylogenetic relationship and the population structure of 500 individuals from the Christian community of Lahore, Pakistan, were examined based on 15 autosomal short tandem repeats (STRs) using the AmpFℓSTR Identifiler Plus PCR Amplification Kit and our previously published Y-filer kit data (17 Y-STRs) of same samples. A total of 147 alleles were observed in 15 loci and allele 11 at the TPOX locus was the most frequent with frequency value (0.464). The data revealed that the Christian population has unique genetic characteristics with respect to a few unusual alleles and their frequencies relative to the other Pakistani population. Significant deviations from Hardy-Weinberg equilibrium were found at two loci (D13S317, D18S51) after Boneferroni's correction (p ≤ 0.003). The combined power of discrimination, combined power of exclusion and cumulative probability of matching were 0.999999999999999978430815060354, 0.999995039393942 and 2.15692 × 10-17, respectively. On the bases of genetic distances, PCA, phylogenetic and structure analysis Lahore-Christians appeared genetically more associated to south Asian particularly Indian populations like Tamil, Karnataka, Kerala and Andhra Pradesh than rest of global populations

Computation of Space Heating Energy Requirements and Comparative Analysis of Three Cold Desert Region of Jammu and Kashmir (India) -A Case Study for Solar System Designs

Abstract: The aim of this study is to determine and present heating degree days for three locations in Jammu and Kashmir province of India for solar system designs. The heating energy requirement of a typical residential building of floor area ~100 m 2 in Jammu and Kashmir, has been determined and the heating degree days have been calculated for various base temperatures and are presented in tabular form. The numerical results show that the heat loss from a typical structure in the state is in huge quantity and that can be a significantly reduced in the heating load using well fitted doors and windows

Association of maternal serum ferritin level with preterm labor

Background: Preterm labor is a significant contributor to neonatal morbidity and mortality worldwide. Identifying reliable biomarkers for predicting preterm birth can improve maternal and neonatal outcomes. Serum ferritin, an acute-phase reactant and iron storage protein, may play a role in the pathophysiology of preterm labor. This study aimed to evaluate the association between maternal serum ferritin levels and preterm labor. Methods: A case-control study was conducted in the Department of Obstetrics and Gynaecology at Dhaka Medical College Hospital from June 2022 to May 2023. A total of 88 pregnant women were enrolled using purposive sampling, including 44 with preterm labor (cases) and 44 with term labor (controls). Sociodemographic, obstetric, and biochemical data were collected, and maternal serum ferritin levels were measured. Data were analyzed using statistical package for the social sciences (SPSS) version 25, and comparisons between groups were made using the Mann-Whitney U test and Chi-square test where appropriate. Results: There was no significant difference in maternal age between the two groups. However, serum ferritin levels were significantly higher in the preterm group (89.09±106.07 ng/ml) compared to the term group (32.13±31.40 ng/ml) (p=0.004). A weak but statistically significant negative correlation was observed between serum ferritin levels and gestational age (r=-0.313, p&lt;0.05). Conclusions: Elevated maternal serum ferritin levels are significantly associated with preterm labor. Serum ferritin may serve as a useful biomarker for identifying women at risk of preterm delivery, allowing for timely interventions to prevent adverse pregnancy outcomes

A Novel Application of Quantum Speed Limit to String Theory

In this work, we investigate the implications of the concept of quantum speed limit in string field theory. We adopt a novel approach to the problem of time on world-sheet based on Fisher information, and arrive at a minimum time for a particle state to evolve into another particle state. This is done using both the Mandelstam-Tamm bound and the Margolus-Levitin bound. This implies that any interaction has to be smeared over such an interval, and any interaction in the effective quantum field theory has to be non-local. As non-local quantum field theories are known to be finite, it is expected that divergences should be removed from effective quantum field theories due to the quantum speed limit of string theory.Comment: 9 page

Synthesis, Characterization, Antibacterial, α-Glucosidase Inhibition and Hemolytic Studies on Some New N-(2,3- Dimethylphenyl)benzenesulfonamide Derivatives

Purpose: To synthesize a series of new N-(2,3-dimethylphenyl)benzenesulfonamide derivatives with pharmacological analysis.Methods: N-(2,3-Dimethylphenyl)benzenesulfonamide (3) was synthesized by the reaction between 2,3-dimethylaniline (1) and benzenesulfonyl chloride (2) in aqueous basic medium. Compound 3 was further treated with various alkyl/aralakyl halides (4a-m) to yield new compounds, 5a-m, in a weak basic aprotic polar organic medium. The proposed structures of synthesized compounds were confirmed using proton-nuclear magnetic resonance (1H-NMR), infra red spectroscopy (IR) and electron impact mass spectrometry (EIMS). The synthesized compounds were screened for in vitro antibacterial, antienzymatic and hemolytic activities using standard procedures.Results: All the synthesized compounds showed moderate to high activity against Gram-positive and Gram-negative bacterial strains. The molecules 5g and 5j exhibited good inhibition of α-glucosidase enzyme with half-maximal inhibitory concentration (IC50) of 59.53 ± 0.01 and 55.31 ± 0.01 μmoles/L, respectively, relative to acarbose with IC50 of 38.25 ± 0.12 μmoles/L. All the compounds exhibited cytotoxicity levels ranging from 27.20 ± 0.24 to 5.20 ± 0.41 %, relative to Triton X-100.Conclusion: Compound 5f is the most potent antibacterial while 5j is the best α-glucosidase inhibitor; 5e showed the least cytotoxicity.Keywords: 2,3-Dimethylaniline, Antibacterial activity, Anti-enzymatic activity, α-Glucosidase inhibitor, Hemolytic activity, Sulfonamide

Morpho-physiological growth performance and phytoremediation capabilities of selected xerophyte grass species toward Cr and Pb stress

Being sessile organisms, plants cannot escape unwanted changes in the environment. The rapid human population explosion caused significant environmental problems. Heavy metals produced through various sources can cause severe damage to living organisms. The study was planned to evaluate four grass species’ morpho-physiological growth characteristics and phytoremediation capabilities under chromium (Cr) and lead stress (Pb) in the arid climate. Typha angustifolia, Tragus roxburghii, Aeluropus logopoides, and Cenchrus ciliaris grass species were used for the study. One-year-old stubbles from the Cholistan desert were used for the experiment. Cr treatments in the form of K2Cr2O7 were applied at 0, 20, 40, and 80 mg L–1, whereas Pb was applied as PbCl2 at 0, 50, 200, and 500 mg L–1 as control, low, moderate and high-stress, respectively. After 6 weeks of heavy metals treatments, plants were harvested and analyzed for growth performance and phytoremediation capabilities. Results depicted that, regarding morphological attributes, T. angustifolia performed better, followed by C. ciliaris; no clear pattern was observed for T. roxburghii and A. logopoides. The CO2 assimilation rate (Co2d) and water use efficiency (WUE) increased as the heavy metal stress increased in all species under both metals. In contrast, total chlorophyll content was higher under low stress. Other physiological parameters, such as relative humidity (RHd), net photosynthetic rate (A), transpiration rate (E), stomatal conductance (Gs), leaf internal CO2 concentration (Ci) and membrane stability index (MSI) gradually decreased as the Cr, and Pb stress levels increased among all the species. Moreover, Cr and Pb absorption contents of T. angustifolia were higher than the other three species at each stress level. Overall, T. angustifolia thrived against heavy metals stress and showed higher biomass, maximum photosynthetic measurements, WUE and higher metal absorption among all the selected species. Results concluded that although all the selected species behaved fine under stress conditions, T. angustifolia performance was better; thus, it can be used to remediate the soil near industrial estates