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Abstract At extreme energies, both low and high, the spacetime symmetries of relativistic quantum field theories (QFTs) are expected to change with Galilean symmetries emerging in the very low energy domain and, as we will argue, Carrollian symmetries appearing at very high energies. The formulation of Wilsonian renormalisation group seems inadequate for handling these changes of the underlying Poincare symmetry of QFTs and it seems unlikely that these drastic changes can be seen within the realms of relativistic QFT. We show that contrary to this expectation, changes in the spacetime algebra occurs at the very edges of parameter space. In particular, we focus on the very high energy sector and show how bilinears of U(1) currents added to a two dimensional (massless) scalar field theory deform the relativistic spacetime conformal algebra to conformal Carroll as the effective coupling of the deformation is dialed to infinity. We demonstrate this using both a symmetric and an antisymmetric current-current deformation for theories with multiple scalar fields. These two operators generate distinct kinds of quantum flows in the coupling space, the symmetric driven by Bogoliubov transformations and the antisymmetric by spectral flows, both leading to Carrollian CFTs at the end of the flow.

Background: Serum prolactin level has been previously used in distinguishing epileptic seizure from non-epileptic seizure, as prolactin level usually rises following an epileptic seizure in children. Aims and Objectives: We conducted this study to determine the role of serum prolactin as a surrogate marker of seizure disorder and whether serum prolactin level varies between different types of seizure, febrile seizure, and seizure mimics. Materials and Methods: This cross-sectional comparative study was conducted for 1 year among 113 children between 6 months and 16 years of age of either sex. They were divided into 3 groups (1) epileptic seizure, (2) febrile seizure, and (3) seizure mimics. The blood sample was collected within 1 h of the occurrence of seizure for estimation of serum prolactin level. Each child was investigated and treated according to the protocol. Results: Mean post-ictal prolactin level was found significantly higher in epileptic seizure (29.94±7.97 ng/mL) compared to febrile seizure (10.21±0.94 ng/mL), and seizure mimics (8.73±0.67 ng/mL). Among group 1, serum prolactin levels significantly elevated in children with generalized tonic-clonic seizure (GTCS) (34.18±2.76 ng/mL) and complex partial seizure (CPS) (31.38±1.59 ng/mL) compared to simple partial seizure (SPS) (14.36±2.33 ng/mL). Post-ictal serum prolactin levels remain elevated for a longer duration in GTCS (54.26±5.19 min) and CPS (45.19±1.73 min) compared to children with SPS (26.76±2.33 min). Conclusion: Estimation of serum prolactin level within 1 h after a seizure can be used for screening purposes to distinguish between epileptic and non-epileptic seizures. A high prolactin level is suggestive of GTCS or CPS whereas a low level is indicative of SPS, febrile convulsion, or seizure mimics with a prolactin cutoff taken 24 ng/mL in our study.

ABSTRACTOpen pit technique is often the simplest and most cost effective mining technology. Coal mining, which began in 1774 in Raniganj, West Bengal, India, led to many abandoned pits, which led to the formation of pit lakes. Mining has a tablvariety of environmental ramifications around the world. On the other hand, the pit lakes of the Raniganj coal field (RCF) are being used for recreational purposes. Knowledge of the spatial pattern in the zooplankton population and surface water quality in pit lakes waters of the Raniganj coal field region is rather limited. Sixteen pit lakes in the RCF in West Bengal, India, were investigated from January 2019 to December 2021. In the present study, we analyzed the spatial pattern and mode of distribution of zooplankton communities based on Coefficient of dispersion methods. To perform a comprehensive analysis of the water quality condition of this study area, we apply water quality index (WQI) methods. A total of 51 taxa were identified and the density was primarily dominated by rotifers. The most dominant species were: Brachionus forficula, Paracyclops sp. and Sida sp. Clumped type of zooplankton distribution pattern was observed in the studied pit lakes. The water quality in most of the studied pit lakes was poor. All the water quality parameters showed significant spatial variations as per Kruskal-Wallis test. The clustering technique produces three groups of pit lakes that are particularly convincing as the pit lakes in these groups showed comparable characteristics.

ABSTRACTCoal mine generated open pit lakes are well distributed in Raniganj coal field area, West Bengal, India. This paper screened out ecological state macrophyte index (ESMI), water quality index (WQI) and multivariate statistical methods to assess the ecological status of four pit lakes, Nagrakonda, Joyalbhanga, Dalurbandh, and Kumardihi. Seven water quality parameters (pH, total dissolved solids, dissolved oxygen, Secchi depth nitrate, chloride, and phosphate) and six sediment quality parameters (pH, organic carbon, bulk density, particle density, available nitrogen and phosphorus) were analyzed for one year on a monthly basis from four pit lakes. The abundance and diversity of aquatic macrophytes were also analyzed. In the studied pit lakes, water and sediment quality variables showed significant spatial variation. WQI showed that the water quality in all pit lakes was good and according to ESMI these lakes were categorized into good ecological status. The results of this study indicated the values of water quality and macrophyte based indices highlighted the ecological condition of the pit lakes of the study sites thus should be considered it as reliable tool for assessing of the ecological status of any wetlands.

Abstract Two-dimensional (2d) field theories invariant under the Bondi-Metzner-Sachs algebra, or 2d BMSFTs in short, are putative holographic duals of Einstein gravity in 3d asymptotically flat spacetimes. When defined on a torus, these field theories come equipped with a modified modular structure. We use the modular covariance of the BMS torus two-point function to develop formulae for different three-point structure constants of the field theory. These structure constants indicate that BMSFTs follow the eigenstate thermalization hypothesis, albeit with some interesting changes to usual 2d CFTs. The singularity structures of the structure constants contain information on perturbations of cosmological horizons in 3d asymptotically flat spacetimes, which we show can also be obtained as a limit of BTZ quasinormal modes.

Abstract Non-centrosymmetric molecular crystals have a plethora of applications, such as piezoelectric transducers, energy storage and nonlinear optical materials owing to their unique structural order which is absent in other synthetic materials. As most crystals are brittle, their efficiency declines upon prolonged usage due to fatigue or catastrophic failure, limiting their utilities. Some natural substances, like bone, enamel, leaf and skin, function efficiently, last a life-time, thanks to their inherent self-healing nature. Therefore, incorporating self-healing ability in crystalline materials will greatly broaden their scope. Here, we report single crystals of a dibenzoate derivative, capable of self-healing within milliseconds via autonomous actuation. Systematic quantitative experiments reveal the limit of mechanical forces that the self-healing crystals can withstand. As a proof-of-concept, we also demonstrate that our self-healed crystals can retain their second harmonic generation (SHG) with high efficiency. Kinematic analysis of the actuation in our system also revealed its impressive performance parameters, and shows actuation response times in the millisecond range.

Background: When a neonate is born under a hypoxic state, there is increased production of uric acid due to hypoxic tissue damage, which is excreted via the kidney, and the ratio of uric acid and creatinine (UA/Cr) in urine is used as an early predictor of perinatal hypoxia. Objectives: We conducted this study to compare urine UA/Cr ratio between normal and asphyxiated newborns and between different stages of HIE to evaluate its usefulness as a diagnostic and prognostic marker of perinatal asphyxia. Patients and method: This observational cross-sectional study is conducted for one year with 75 asphyxiated neonates in different stages of HIE and 75 healthy neonates as control. Uric acid and creatinine values are measured with an auto-analyzer from a single urine sample taken between 6 to 24 hours of birth. Results: We found urine UA(38 ±2.81 mg/dl vs 19.24±0.75 mg/dl ) and urine UA/Cr value (2.81±0.32 vs 1.40±0.13 ) significantly high in cases compared to control. Also, the urine UA and UA/Cr values are increasing with advanced stages of HIE (p 2.45 with an AUC of 0.96, accuracy of 90%, sensitivity of 98.07% , specificity of 85.70% , PPV 78.46%, and NPV 98.82%. Conclusion: Urine UA/Cr appears to be a simple, inexpensive and reliable indicator of perinatal hypoxia for risk stratification based on functional impairment in the HIE babies.

Abstract The Carroll algebra is constructed as the c → 0 limit of the Poincare algebra and is associated to symmetries on generic null surfaces. In this paper, we begin investigations of Carrollian fermions or fermions defined on generic null surfaces. Due to the availability of two different (degenerate) metrics on Carroll spacetimes, there is the possibility of two different versions of Carroll Clifford algebras. We consider both possibilities and construct explicit representations of Carrollian gamma matrices and show how to build higher spacetime dimensional representations out of lower ones. Actions for Carroll fermions are constructed with these gamma matrices and the properties of these actions are investigated. We show that in condensed matter systems where the dispersion relation becomes trivial i.e. the energy is not dependent on momentum and bands flatten out, Carroll symmetry generically appears. We give explicit examples of this including that of twisted bi-layer graphene, where superconductivity appears at so called magic angles and connect this to Carroll fermions.

Context: The COVID-19 vaccination drive globally was supposedly a game-changing event. However, the emerging variants of the virus and waning immunity over time posed new challenges for breakthrough infections. Standing at the frontline of defense against COVID-19, healthcare personnel (HCP) were vulnerable to such infections. Aims: This study estimates i) the vaccine breakthrough infections (VBI) among HCP following exposure to COVID-19 cases, and ii) the mean interval between the second dose of vaccine and laboratory-confirmed SARS-CoV-2 infection. Materials and Methods: A cross-sectional study was conducted including 385 HCP with a history of exposure to COVID-19 cases during January and February 2022. Demographic details and clinical and vaccination history were collected from the test forms and the Web-based hospital management system. Laboratory testing of COVID-19 was carried out by real-time RT-PCR test. Results: The majority of the HCP were males (262; 68.05%) and nurses (180; 46.75%) by occupation. Two doses of vaccines were received by 278 (87.7%) HCP. VBI was confirmed in 185 (66.55%) HCP. No significant difference in VBI between the COVAXIN and COVISHIELD recipients (P = 0.69) was observed. The interval between the second dose and confirmed SARS-CoV-2 infection was significantly higher (P < 0.00001) in COVAXIN recipients (median 228 days) than in COVISHIELD recipients (median 95 days). Conclusions: The incidence of VBI was very high among the HCP, but not statistically different among the COVAXIN and COVISHIELD-recipients. Waning immunity over time suggests boosting immunity with a third dose because of emerging variants.

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an important cause of neonatal indirect hyperbilirubinemia or even kernicterus leading to long-term neurological sequelae specially in countries like India where G6PD deficiency is quite prevalent. Aims and Objectives: We have planned this study to know the prevalence of G6PD deficiency among cases of neonatal jaundice and also to evaluate the difference between G6PD deficient and normal neonates with indirect hyperbilirubinemia in terms of laboratory parameters and need of phototherapy or exchange transfusion. Materials and Methods: This observational and cross-sectional study was done for a period of 1 year in the SNCU and NICU of a district Medical College of West Bengal among 200 term neonates presented with indirect hyperbilirubinemia. Birth weight, sex, hemoglobin, G6PD level, serum bilirubin at admission, phototherapy duration, and need for exchange transfusion were recorded along with other necessary parameters. Results: We found G6PD deficiency in 24 neonates (12%) out of 200 cases of neonatal jaundice, 20 of whom were male. There is a statistically significant difference in hemoglobin and serum bilirubin level between two groups. Difference in early presentation of jaundice within 24–48 h (66.7% vs. 34.1%) and need of prolonged phototherapy 72–96 h (45.83% vs. 7.4%) between G6PD deficient and normal group were statistically significant. Difference in requirement of exchange transfusion is not statistically significant. Conclusion: Early screening for G6PD deficiency should be considered in every neonates of G6PD deficient endemic countries so that we can predict the natural course of the jaundice in those G6PD deficient neonate and prevent complication by early initiation of phototherapy or exchange transfusion.

The Sundarban biosphere reserve is the largest mangrove forest in the world, situated partially in India and Bangladesh. This eco-sensitive estuarine delta is designated by UNESCO as a world heritage site. The population density of this estuarine forest region has been relatively low for a long past, but in last few decades it is increasing rapidly, especially after the partition of India. This is creating an immense pressure on forest resources. Mangrove forest area has been converting into arable land, putting all natural animal and local people in a precarious situation. The Sundarban usually is the home of Royal Bengal Tiger, one of the famous endangered species. Due to massive deforestation the habitat of tigers is being destroyed and as a result tigers sometimes attack nearby villagers. The forest dwellers of Sundarban are dependent on the forest resources for their livelihood for which they collect wax, honey, firewood etc. Such human intervention in the forest is changing the composition of core, outer core and buffer forests of Sundarban. This results an increased human–tiger conflict in the study area. The present research work aims to enquire the probable reason of such. Following an intensive study it has been found that, the outer-core of the forest areas are the most vulnerable part of the forest where most of the human–tiger conflicts have been reported and most of the casualties have been identified among the people who are entirely dependent of forest resources for their livelihood.

Nano-crystalline titanium dioxide (TiO2) photocatalyst has been extensively utilized in the last few decades because of its strong oxidizing power, redox selectivity, and higher photocatalytic performance. In this work, TiO2 nanoparticle (NPs) was synthesized, characterized, and applied for the degradation of methyl orange (MO) dye in an aqueous solution under UV and solar light irradiations. The XRD results showed dominated anatase phase (82%) with a smaller crystalline size (18.23 nm). A rough surface with a uniform spherical shape was observed by SEM analysis. FTIR and UV–Vis/DRS spectroscopy confirmed the stretching vibration of the hydroxyl groups and higher absorption edge towards longer wavelength with smaller bandgap energy (3.12 eV) of TiO2 lattice structure. The activity of TiO2 NPs was carried out from the degradation of MO dye as a model contaminant for textile effluent in presence of UV/solar irradiation. The photodegradation efficiency of MO dye (15 mg L−1) was observed at 85.90% and 96.38% for 0.150 g and 0.030 g of TiO2 NPs at natural pH (7.0), after 5 h of UV and solar light irradiation. The respective rate constants were determined to be 0.0063 min−1 and 0.01 min−1 for UV and simulated solar light irradiation respectively, and exhibited the best-fitted kinetic model of pseudo-first-order. The photodegradation efficiency was increased with the decrease of pH, while efficiency decreased with an increase in initial dye concentration. The obtained result from TiO2 NPs was compared with commercially available Degussa P25 catalyst. The photocatalyst reusability test and reaction mechanism were also evaluated. The study suggests that TiO2 NPs are a promising photocatalyst that can be used for the degradation of organic dye compounds from textile wastewater towards the sustainable management of environment.

Background: Neonatal sepsis and meningitis is an important cause of neonatal mortality and morbidity especially in the developing countries. Bacteriological profile of meningitis and antibiotic sensitivity pattern may vary from one region to another. Aims and Objectives: We have planned this study to know the etiological agent of neonatal meningitis with its antibiotic sensitivity profile and to evaluate some other associated risk factors of meningitis. Materials and Methods: This observational, cross-sectional study was done for a period of 1 year in the SNCU and NICU of a district Medical College of West Bengal in neonates presented with clinical sepsis and meningitis. Sepsis screen, blood culture, cerebrospinal fluid (CSF) study, and culture sensitivity was done and recorded along with demographic data, clinical presentation, outcome, and other associated factors. Results: We found meningitis in 55 neonates out of 250 clinical sepsis. CSF culture was positive in 42 cases with Escherichia coli (30.9%), Klebsiella (26.1%), Staphylococcus aureus (16.6%), Acinetobacter (14.2%) and Coagulase negative Staphylococcus (CoNS 11.9%) as prevalent organism. E. coli and Klebsiella were mostly sensitive to Amikacin, Levofloxacin, and Colistin whereas less sensitive to Cefotaxime, Pipercilin-tazobactam or Meropenem and Acinetobacter showed good sensitivity only to Levofloxacin. Among the gram-positive organism, S. aureus and CoNS were only sensitive to Linezolid, Vancomycin, and Teicoplanin. Conclusion: This type of study should help to make a proper antibiotic policy for an institution so that the empirical first-line antibiotic can be started with good effect in cases of neonatal sepsis and meningitis before the arrival of culture sensitivity report.

Background: Early diagnosis and treatment of drug-resistant tuberculosis (TB) is crucial to halt the spread of drug resistance in the community. Aim: The aim of the study was to compare rapid diagnostic tests (GeneXpert and line probe assay, LPA) with conventional liquid culture for the diagnosis of drug-resistant TB and to assess the risk factors for it. Method: This cross-sectional study recruited 229 multidrug-resistant TB suspects who were sputum smear positive. They were evaluated by the rapid diagnostic tests and sensitivity, specificity, positive predictive value and negative predictive value were calculated for drug resistance detection as compared to liquid culture drug susceptibility testing. The risk factors for the development of drug resistance were also assessed and the P value of < 0.05 was considered significant. Results: In the final comparison, 193 samples were included. The sensitivity and specificity of GeneXpert for detection of drug resistance (rifampicin) was 100% (95% confidence interval, CI: 88.8–100%) and 99.4% (95% CI: 96.6–99.9%), respectively. Whereas sensitivity and specificity of LPA was 94.3% (95% CI: 80.8–99.3%) and 100% (95% CI: 97.7–100%), respectively. Only three discordant samples were observed. Defaulting to antitubercular therapy, contact with resistant TB, and disseminated disease were found to be significant risk factors for the development of drug-resistant TB with high statistical significance (P value < 0.05). Conclusion: Both rapid diagnostic tests have very high sensitivity and specificity for detection of drug resistance in sputum smear positive with the advantage of short turn-around time. Defaulting to antitubercular therapy, contact with resistant TB, and disseminated disease are significant risk factors for drug resistance.

Harmonic Radio Frequency Identification (RFID) systems have attracted significant interest over the last decade as it provides many benefits over the conventional RFID systems. Harmonic RFID is desired over conventional RFID systems due to reduced self-jamming, location accuracy from dual frequency, and higher phase noise immunity. In a harmonic RFID system, the tag receives instructions from the reader at an RF carrier frequency and replies back at the harmonic of the RF frequency. A nonlinear element consuming very low power at the tag is required to generate the harmonic carrier for the battery-less system. In this review article, a detailed contrast between conventional and harmonic RFID systems is presented. This is followed by different circuit design techniques to generate harmonics and integration techniques to form a fully operable passive harmonic RFID tag. Also, a wide range of applications, especially sensor integration with harmonic RFID’s, along with the future trends are presented.

In this paper, an efficient passive wireless harmonic communication system is proposed for the real-time monitoring of the pressurized pipelines. A pressure sensor is fabricated using the additive manufacturing technique and a harmonic radio frequency (RF) tag is designed to operate at the fundamental frequency (fo) of 2 GHz that shifts the phase of the back reflected RF signal according to the applied pressure ranging from 0 to 20 psi. A power efficient phase modulation with virtually no losses is achieved using a hybrid coupler-based phase shifter that efficiently reflect back the incoming signal using an end coupled reactive impedance element/sensor. The phase delay introduced by the reactive element gets doubled with the second harmonic communication, which increases the sensitivity by a factor of two. The concept of harmonic backscattering is exploited to reduce the effects of multi-path interference and self jamming, as well as improving the signal-to-noise ratio (SNR).

Background: Thalassemias and hemoglobinopathies are highly prevalent in India. Identification of these disorders is important for epidemiologic purposes and for prevention of thalassemia major and clinically severe hemoglobinopathies. Objectives: The aim of this study was to determine the prevalence of thalassemias and hemoglobinopathies in patients of a tertiary care hospital of West Bengal. Materials and Methods: A prospective study was undertaken in which 90,210 cases were included over a period of 8 years. Clinical history and family history were obtained from each patient. The venous blood samples were analyzed for complete blood count, liver function tests, serum iron, ferritin, cobalamin and folate levels. High-performance liquid chromatography (HPLC) was performed on the samples with Biorad Variant using beta thalassemia short program. Confirmatory tests were done whenever required. Results: Normal hemoglobin (Hb) pattern was observed in 79,897 (88.57%) cases and abnormalities were detected in 10,313 (11.43%) patients. β (beta) thalassemia trait was the most common abnormality found in 3870 (4.29%) patients. HbE trait was found in 2418 (2.68%) cases, and then Eβ thalassemia in 1406 (1.56%) patients and β thalassemia major/intermedia in 1135 (1.26%) cases. Other variants detected included sickle cell trait, HbE disease, sickle cell disease, sickle β thalassemia, HbD-Punjab trait, double heterozygous state of HbS and HbE, double heterozygous state of HbS and HbD, Hb Lepore, HbJ-Meerut and HbH. Conclusion: Premarital and antenatal screenings are important measures to prevent birth of children with severe Hb disorders. HPLC is a rapid and reliable technique for identification of various Hb fractions.