First principles electron-correlated calculations of optical absorption in magnesium clusters

In this paper, we report large-scale configuration interaction (CI) calculations of linear optical absorption spectra of various isomers of magnesium clusters Mg$_{n}$ (n=2--5), corresponding to valence transitions. Geometry optimization of several low-lying isomers of each cluster was carried out using coupled-cluster singles doubles (CCSD) approach, and these geometries were subsequently employed to perform ground and excited state calculations using either the full-CI (FCI) or the multi-reference singles-doubles configuration interaction (MRSDCI) approach, within the frozen-core approximation. Our calculated photoabsorption spectrum of magnesium dimer (Mg$_{2}$) isomer is in excellent agreement with the experiments both for peak positions, and intensities. Owing to the sufficiently inclusive electron-correlation effects, these results can serve as benchmarks against which future experiments, as well as calculations performed using other theoretical approaches, can be tested.Comment: 23 pages and 21 figures of main tex

Large-scale first principles configuration interaction calculations of optical absorption in boron clusters

We have performed systematic large-scale all-electron correlated calculations on boron clusters B$_{n}$(n=2--5), to study their linear optical absorption spectra. Several possible isomers of each cluster were considered, and their geometries were optimized at the coupled-cluster singles doubles (CCSD) level of theory. Using the optimized ground-state geometries, excited states of different clusters were computed using the multi-reference singles-doubles configuration-interaction (MRSDCI) approach, which includes electron correlation effects at a sophisticated level. These CI wave functions were used to compute the transition dipole matrix elements connecting the ground and various excited states of different clusters, eventually leading to their linear absorption spectra. The convergence of our results with respect to the basis sets, and the size of the CI expansion were carefully examined. The contribution of configurations to many body wavefunction of various excited states suggests that the excitations involved are collective, plasmonic type.Comment: 25 page, 13 figures (included); Invited article for a special issue titled "Theoretical Simulation and Computational Design of Nanomaterials and Biomaterials", of the journal Nano Lif

Study of Performance Characteristics of a Triple Duty Valve using CFD

A triple duty valve is used to control the functions such as on-off, throttling and non-return on the discharge side of hydronic pump systems. In this paper, computational fluid dynamic techniques are used to simulate the 2 inch triple duty valve performance characteristics for various stroke lengths with uniform outgoing velocity. The performance characteristics such as flow coefficient and pressure loss coefficient for triple duty valve are calculated for different stroke lengths (8 mm, 12 mm and 20 mm) through simulation. Numerical simulation is conducted to study effect of various Reynolds number and valve openings on the performance characteristics of triple duty valve. The permanent pressure loss coefficient and its dependence on Reynolds number is computed and analyzed respectively so that the recovery of pressure after passage through valve could be quantitatively understood. The comparison of flow pattern at different stroke length is investigated. Pressure drop across the triple duty valve and formation of vortex flow after the valve section have been discussed. Magnitude of flow coefficient, pressure loss coefficient and permanent pressure loss coefficient calculated through numerical analysis are compared with the experimental results. Furthermore, this study can be used for the evaluation of performance characteristics of triple duty valve at different sizes

Invasive Alien Species of Terrestrial Vegetation of North-Eastern Uttar Pradesh

The vegetational landscape of north-eastern Terai region at the foot hills of Central Himalayas is a mosaic of grassland, old-field, wasteland, and forest ecosystems. Like many other parts of the country, this region is also infested with alien intruders which not only interfere with the growth and production of food crops but also exercise adverse effects on the biodiversity of native species. The present study attempts to catalogue the invasive alien species of the terrestrial vegetation of north-eastern Uttar Pradesh especially with reference to their habit, taxonomic position, and nativity. A total of 1135 plant species within 580 genera under 119 families are so far known to occur in the region. Of these, only 149 species within 100 genera under 41 families have been found to be invasive aliens as evident from their center of origin, past history, nature of aggregation, and invasion observed under field conditions. About 80% of these invaders have been introduced from neotropics. Out of 173 invasive plants across India, this region shares 149 species, out of which 66% of species have come from Tropical America, 14% from African continent, and the rest from other countries. A better planning in the form of early identification and reporting of infestation and spread of noxious weeds is needed for their control

The Robot-Assisted Extravesical Anti-reflux Surgery: How We Overcame the Learning Curve

Management of vesicoureteral reflux (VUR) has evolved over the past several decades, with a trend toward a decrease in surgical management. In spite of this, ureteral reimplantation remains a commonly performed procedure by pediatric urologists in selected cases. Although the basic tenets of the ureteral reimplant procedure remain the same, the extra- vs. intravesical approach, and the traditional open vs. minimally invasive approach remain the primary options to correct reflux. Considering the advantages conferred by the robotic surgery platform, many leading centers have preferentially adopted robot-assisted laparoscopic extravesical anti-reflux surgery, or in common surgical parlance, the robot-assisted laparoscopic ureteral reimplantation (RALUR), over pure laparoscopic or open approaches. Predicated on our experience of performing over 170 cases of RALUR, we have made technical modifications which we posit reduce the morbidity of the procedure while offering acceptable outcomes. This review highlights the evolution and establishment of RALUR as a standardization of care in the surgical management of VUR at our institution. In particular, we emphasize the technical nuances and specific challenges encountered through the learning curve in hopes of facilitating this process for others

Geospatial mapping of antimalarial plants used by the ethnic groups of Anuppur district (Madhya Pradesh, India)

261-271The present ethnobotanical study was conducted to document indigenous knowledge and practices for treatment of malaria in Annupur district, Madhya Pradesh, India. This paper also reports on geographical distribution of prevalent antimalarial plants. Information was collected from 29 traditional healers and 240 other informants about their socio-economy and knowledge of plants by means of semi-structured questionnaires-SSQ and interview-SSI. Global Positioning System (GPS) coordinates were recorded for marked locations and integrated in ArcGIS to develop geospatial map. A total of 19 plants belonging to 15 families were identified against malaria. Majority of these were growing wild in forest area (57.89%). Andrographis paniculata was the most cited plant (19.23%) followed by Vitex negundo (10.57%). Highest AMI was recorded for A. paniculata (0.338), whereas, lowest (0.029) for Schefflera vinosa and Datura metel. Synergic antimalarial recipes prepared from two or more plants were preferred over single plant recipe. Roots (63.15%) were the most frequently used plant part followed by leaves (42.10%) and seeds (21.05%). This is the first ethnopharmacological documentation of antimalarial plants in Central India. It highlights potential sources for the development of novel antimalarial remedies from indiginous traditional knowledge. The spatial maps facilitate the access of local tribal population to these plants

Thyroid Nodule: Approach and Management

A thyroid nodule is a discrete radiologically distinct lesion in the gland parenchyma. These are a common finding in the general population, majority being diagnosed incidentally during neck imaging. The major clinical relevance lies in the fact that 4–6.5% of nodules can be malignant. A thorough clinical evaluation and examination should be followed by serum TSH assessment and ultrasonography for assessment of size, number, imaging characteristics suggestive of malignancy, cervical lymphadenopathy. FNA should be done based on clinical and sonographic characteristics. Further choice of management modality and extent of surgery should be based on cytopathological findings supplemented by molecular testing if available

A Pan-India, Knowledge, Attitudes and Practices (KAP) Study of Healthcare Practitioners in India Regarding Immunomodulatory Role of Vitamin D Supplementation in COVID-19

Introduction: Vitamin D has immunomodulatory effects and vitamin D deficiency has been associated with autoimmune responses and increased risk of infections. Vitamin D-mediated antimicrobial and anti-inflammatory responses play an effective role in the prevention of various respiratory tract infections including coronavirus disease 2019 (COVID-19). Aims and objective: To evaluate the therapeutic role of vitamin D via immunomodulation in COVID-19 through a Knowledge, Attitudes and Practices (KAP) study of pan India healthcare practitioners (HCPs) to arrive at a common consensus statement regarding dosage and duration of vitamin D for immune-modulatory function. Methods: A pan-India, online, questionnaire-based, KAP survey was conducted on vitamin D and its role in immunomodulation in COVID-19 from April 2021 to January 2022 followed by polling obtained from 2,338 HCPs through round table meetings (RTMs). Results: Approximately 64% of HCPs considered the use of vitamin D in COVID-19 patients for various reasons including prevention of illness, reduced ICU stay, reduction in morbidity and mortality along with decrease in the levels of inflammatory markers in COVID-19 patients. For the dosage regime, 47% of HCPs preferred vitamin D 60,000 IUweekly while 45% of HCPs preferred both 60,000 IU weekly and 2,000 IU daily dose for boosting immune system in their patients. Conclusion: The panel agreed that vitamin D levels of 40 ng/mL and above appear to confer better immune-protective response to several infections including COVID-19

Optical absorption in boron clusters B6_{6} and B6+_{6}^{+} : A first principles configuration interaction approach

The linear optical absorption spectra in neutral boron cluster B$_{6}$ and cationic B$_{6}^{+}$ are calculated using a first principles correlated electron approach. The geometries of several low-lying isomers of these clusters were optimized at the coupled-cluster singles doubles (CCSD) level of theory. With these optimized ground-state geometries, excited states of different isomers were computed using the singles configuration-interaction (SCI) approach. The many body wavefunctions of various excited states have been analysed and the nature of optical excitation involved are found to be of collective, plasmonic type.Comment: 22 pages, 38 figures. An invited article submitted to European Physical Journal D. This work was presented in the International Symposium on Small Particles and Inorganic Clusters - XVI, held in Leuven, Belgiu