Testing the Kerr nature of intermediate-mass and supermassive black hole binaries using spin-induced multipole moment measurements

The gravitational wave measurements of spin-induced multipole moment coefficients of a binary black hole system can be used to distinguish black holes from other compact objects [N. V. Krishnendu et al., PRL 119, 091101 (2017)]. Here, we apply the idea proposed in [N. V. Krishnendu et al., PRL 119, 091101 (2017)] to binary systems composed of intermediate-mass and supermassive black holes and derive the expected bounds on their Kerr nature using future space-based gravitational wave detectors. Using astrophysical models of binary black hole population, we study the measurability of the spin-induced quadrupole and octupole moment coefficients using LISA and DECIGO. The errors on spin-induced quadrupole moment parameter of the binary system are found to be { $\leq 0.1$ for almost $3\%$ of the total supermassive binary black hole population which is detectable by LISA whereas it is $\sim 46\%$ for the intermediate-mass black hole binaries observable by DECIGO at its design sensitivity.} We find that { errors on} {\it both} the quadrupole and octupole moment parameters can be estimated to { be} $\leq 1$ for $\sim 2\%$ and $\sim 50\%$ {of the population} respectively for LISA and DECIGO detectors. { Our findings suggest that a subpopulation of binary black hole events, with the signal to noise ratio thresholds greater than 200 and 100 respectively for LISA and DECIGO detectors, would permit tests of black hole nature to 10\% precision.}Comment: 7 pages, 6 figure

Targeted therapies in the management of locally advanced and metastatic pancreatic cancer: a systematic review

Pancreatic cancer has a dismal prognosis particularly in patients presenting with unresectable tumors. We performed a bibliometric analysis of clinical trials for pancreatic cancer conducted between 2014-2016 focusing on patients that presented with unresectable (locally advanced or metastatic) tumors. We discuss a range of studies that employed FOLFIRINOX, the gemcitabine + nab-paclitaxel combination and studies that used molecularly-targeted therapy. Major areas of focus have been dual targeting of EGFR and VEGFR, immunotherapy or a multimodal approach – combining chemotherapy with radiotherapy. We also point out the need for molecular selection for low prevalence subtypes. Key insights sourced from these pivotal trials should improve clinical outcomes for this devastating cancer

Electrochemical Discharge Machining Process

Electrochemical discharge machining process is evolving as a promising micromachiningprocess. The experimental investigations in the present work substantiate this trend. In the presentwork, in situ, synchronised, transient temperature and current measurements have been carriedout. The need for the transient measurements arose due to the time-varying nature of the dischargeformation and time varying circuit current. Synchronised and transient measurements revealedthe discrete nature of the process. It also helped in formulating the basic mechanism for thedischarge formation and the material removal in the process. Temperature profile on workpieceand in electrochemical discharge machining cell is experimentally measured using pyrometer,and two varieties of K-type thermocouples. Surface topography of the discharge-affected zoneson the workpiece has been carried out using scanning electron microscope. Measurements andsurface topographical studies reveal the potential use of this process for machining in micronregime. With careful experimental set-up design, suitable supply voltage and its polarity, theprocess can be applied for both micromachining and micro-deposition. It can be extended formachining and or deposition of wide range of materials

Artist Statement

Tapestries 2021-2022 editors Anjali Moore and Nicole Salazar reflect on the creation of volume 11 of the journal

A cross sectional study to estimate prevalence of obesity and its risk factors in adolescent school children in Western Maharashtra, India

Background: There is an increase in prevalence of childhood obesity and its chronic health effects especially in developing countries like India in last 2-3 decades. This study is small effort to know prevalence and risk factors causing obesity. Aim of the study was to estimate prevalence of obesity and its risk factors in school students of age group 11 to 16 years.Methods: About 207 adolescent school children from selected school were enrolled in the study. Research tool comprised of questions about demographic characteristics, daily physical activity, frequency of having junk food intake etc. Height and weight were measured on calibrated scales. For statistical analysis MS Excel and SPSS 16 were used.Results: Among participants 58.9% were boys. 66.7% students were in the 13 to 14 years of age group. As per body mass index, 46.9% children were underweight and 8.7% were obese. 77.3% participants were eating junk food more than once in a week.Conclusions: Health education on dietary habits and physical activity is needed for adolescent children to prevent development of obesity and complications related to it

PREVALENCE AND ANTIBIOTIC SUSCEPTIBILITY OF ACINETOBACTERIN A TERTIARY CARE HOSPITAL IN CHENNAI, INDIA

Objective: The present study is to determine the prevalence and antibiotic susceptibility of Acinetobacter species in samples collected from patients in tertiary care hospital in Chennai. Methods: A total of17,827patient’s clinical samples were collected from various wards and ICUs of Saveetha Medical College and Hospital, Chennai, Tamilnadu over a period of 7 mo [between January 2020 and July 2020]. All samples were tested in the microbiology lab of Saveetha Medical College and Hospital using standard operating procedures. Results: Out of 17,827 samples, 2,816 were culture positive. 122 of the isolates tested positive for Acinetobacter spp.and 81.1% of the isolates belonged to Acinetobacterbaumannii. Most of the infection occurred in the age group of 21-40 y and predominantly in female patients (female, male ratio 1.9:1).General wards contributed to 54.9% of the Acinetobacter infection, followed by ICU(27%) and OPD(18%). Maximum isolates were recovered from urine(34.4%) and endotracheal secretions(29.5%).60.7% of the Acinetobacterspp were multidrug-resistant(MDR)i.e. resistant to more than 3 antibiotic group.In our study, most Acinetobactersppwere resistant to penicillin(46-100%), third and fourth generation cephalosporin (36-61.5%), carbapenems (34.4-82.8%)and quinolones(39.3-46.7%). None of the isolates were resistant to colistin. 93.4% ofisolates were sensitive to tigecycline and 87.7% sensitive to amikacin. Conclusion: Our study observed a high incidence of MDR inAcinetobacterspp, which is in line with most of the research findings in recent times. Most of Acinetobacterspp were resistant to penicillin, third and fourth generation cephalosporins, quinolones, carbapenems,which is alarming as it leaves fewer options for the line of treatment. Some strains were sensitive to cefepime, ceftazidime, piperacillin-tazobactam, levofloxacin, imipenem and meropenem. Considering the increasing MDR nature of Acinetobacterspp a combination of the former along with colistin, tigecycline, amikacin(which have shown more than 85% sensitivity) would need to be studied.Also, strict measures to control the spread of Acinetobacter infection, better management of antibiotics usage and newer therapeutic option for treatment need to be looked at

Raman anomalies as signatures of pressure induced electronic topological and structural transitions in black phosphorus: Experiments and Theory

We report high pressure Raman experiments of Black phosphorus up to 24 GPa. The line widths of first order Raman modes A$^1_g$, B$_{2g}$ and A$^2_g$ of the orthorhombic phase show a minimum at 1.1 GPa. Our first-principles density functional analysis reveals that this is associated with the anomalies in electron-phonon coupling at the semiconductor to topological insulator transition through inversion of valence and conduction bands marking a change from trivial to nontrivial electronic topology. The frequencies of B$_{2g}$ and A$^2_g$ modes become anomalous in the rhombohedral phase at 7.4 GPa, and new modes appearing in the rhombohedral phase show anomalous softening with pressure. This is shown to originate from unusual structural evolution of black phosphorous with pressure, based on first-principles theoretical analysis.Comment: 13pages, 12figure