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1.
J Chromatogr A ; 1730: 465091, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38964159

RESUMO

An extraction chromatography resin, prepared by the impregnation of bis-octyloxy-calix[4]arene-mono-crown-6 (BOCMC)onto an acrylic ester based polymeric support material, gave excellent uptake data for the removal of radio-cesium (Cs-137) from nitric acid feed solutions. The weight distribution coefficient (Kd) value of >300 obtained during the present study at 3 M HNO3 was the highest reported so far while using a calix-crown-6 based extraction chromatographic resin material. Analogous resin reported previously has yielded a Kd value <100 at comparable feed conditions. The sorbed metal ions could be efficiently desorbed with de-ionized water. Kinetic modeling of the uptake data indicated that both the film and the intra-particle diffusion mechanism are simultaneously operating in the sorption of Cs+ion onto the BOCMC resin. The metal ion sorption data were fitted to the sorption isotherm models and did not conform to the chemisorptions of physisorption models and indicated a pi-pi interaction between the benzene rings of the calix-crown-6 ligand and the Cs+ ion. The reusability of the resins was quite satisfactory after 5 cycles and the radiation stability of the resin material was very good upto an absorbed dose of 500 kGy. The results of column studies were quite encouraging with 15 mL (9 bed volumes) as the breakthrough volume while the elution was complete in about 12 bed volumes of de-ionized water.

2.
Dalton Trans ; 53(17): 7321-7339, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38591248

RESUMO

The +5 state is an unusual oxidation state of uranium due to its instability in the aqueous phase. As a result, gaining information about its aqueous speciation is extremely difficult. The present work is an attempt in that direction and it provides insight into the existence of a new pentavalent species in the presence of hetero-bifunctional phosphonocarboxylate (PC) chelators, other than the carbonate ion, in the aqueous medium. The aqueous chemistry of pentavalent uranium species with three environmentally relevant PCs was probed using electrochemical and DFT methods to understand the redox energy and kinetics of conversion of the U(VI)/U(V) couple, stability, structure, stoichiometry, binding modes, etc. Interestingly, pentavalent uranium complexes with PCs are quite persistent over a wide range of pH starting from acidic to alkaline conditions. The PC chelators block the cation-cation interaction (CCI) of U(V) through strong hetero-bidentate chelation and intermolecular hydrogen bonding (IMHB) interactions which stabilize the pentavalent metal ion against disproportionation. For uranyl species in the presence of PCs, acting as chelators, CV plots were obtained at varying pH values from 2 to 8. The obtained results indicate an irreversible single redox peak involving U(VI) to U(V) conversion and association of a coupled chemical reaction with the electron transfer step. ESI-MS studies were performed to understand the speciation effect on the U(VI)/U(V) redox couple with varying pH. Speciation modelling of U(V) with the PC ligands was carried out, which indicated that the U(V) is redox stable in nearly 47% of the pH region in the presence of the PCs as compared to the carboxylate-based chelators. The free energy and reduction potential of the U(V) complexes and the reduction free energy and disproportionation free energy for the U(VI)/U(V) couple were determined by DFT computations in the presence of the PCs. In situ spectroelectrochemical spectra were recorded to provide evidence for the existence of U(V) species with PCs in the aqueous medium and to acquire its absorption spectra. The present study is highly significant for understanding the coordination chemistry of pentavalent uranium species, accurate modelling of uranium, and isolation of U(V).

3.
Dalton Trans ; 53(13): 5871-5880, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38415375

RESUMO

Separation of Am3+ and Cm3+ is one of the most challenging yet unavoidable steps in the back end of the nuclear cycle. Various ligands evaluated for Am/Cm separation have their own merits and demerits, and not a single ligand has been uniquely proposed for this purpose. In the present work, we evaluated N,N,N',N'-tetra-n-octyldiglycolamide (TODGA) vis-à-vis N,N,N',N'-tetra-2-ethylhexyldiglycolamide (T2EHDGA) in combination with a hydrophilic 2,6-bis(1,2,4-triazinyl)pyridine (SO3PhBTP) derivative in the aqueous phase for the separation of Am3+ and Cm3+ from nitric acid medium. The results showed that marginal selectivity for Am3+ over Cm3+ was observed with T2EHDGA in the presence of SO3PhBTP, which was attributed to the difference in the entropy change for their extraction from both the temperature-dependent liquid-liquid extraction and computational studies.

5.
Rev Sci Instrum ; 94(4)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38081262

RESUMO

We describe the first implementation of a Josephson Traveling Wave Parametric Amplifier (JTWPA) in an axion dark matter search. The operation of the JTWPA for a period of about two weeks achieved sensitivity to axion-like particle dark matter with axion-photon couplings above 10-13 Ge V-1 over a narrow range of axion masses centered around 19.84 µeV by tuning the resonant frequency of the cavity over the frequency range of 4796.7-4799.5 MHz. The JTWPA was operated in the insert of the axion dark matter experiment as part of an independent receiver chain that was attached to a 0.56-l cavity. The ability of the JTWPA to deliver high gain over a wide (3 GHz) bandwidth has engendered interest from those aiming to perform broadband axion searches, a longstanding goal in this field.

6.
South Asian J Cancer ; 12(2): 93-99, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37969669

RESUMO

Purvish M. ParikhCancer-associated anemia (CAA) remains a major unmet need that compromises overall survival (OS) and quality of life (QoL). Currently, available guidelines do not take into consideration the unique challenges in low- and middle-income countries (LMIC). Our CAA patients have to battle preexisting impaired nutritional status, depleted body iron stores, financial limitations, and difficulty in having easily accessible affordable healthcare. Hence, we fulfilled the need of guidelines for LMIC. A group of subject experts were put together, given background literature, met in a face-to-face discussion, voted using Delphi process, and finally agreed on the contents of this guideline document. As many as 50% of cancer patients will have significant anemia (hemoglobin < 10 g/dL) at initial diagnosis. It is most commonly seen with gastrointestinal malignancies, head and neck cancers, and acute leukemias. The hemoglobin falls further after initiation of cancer directed therapy, due to chemotherapy itself or heightened nutritional deficiency. Its evaluation should include tests for complete blood count, red blood cell morphology, reticulocyte count, Coombs test, and levels of vitamin B12 and folic acid. Iron status should be monitored using test to measure serum iron, total iron binding capacity, transferring saturation, and serum ferritin levels. A minimum of 50% of cancer patients with anemia require iron supplements. The preferred mode of therapy is with intravenous (IV) iron using ferric carboxymaltose (FCM). Most patients respond satisfactorily to single dose of 1000 mg. It is also safe and does not require use of a test dose. Significant anemia is found in at least half of all cancer patients in India, South Asian Association for Regional Cooperation region, and other LMIC countries. Its awareness among healthcare professionals will prevent it from remaining undiagnosed (in up to 70% of all cancer patients) and adversely affecting OS and QoL. The benefits of treating them with IV iron therapy are quick replenishment of iron stores, hemoglobin returning to normal, better QoL, and avoiding risk of infections/reactions with blood transfusions. Many publications have proven the value of single-dose FCM in such clinical situations. CAA has been proven to be an independent prognostic factor that adversely affects both QoL and OS in cancer patients. Use of FCM as single IV dose of 1000 mg is safe and effective in the majority of patients with CAA.

7.
BMC Cancer ; 23(1): 737, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37558975

RESUMO

In advanced Renal Cell Carcinoma (aRCC), systemic therapy is the mainstay of treatment, with no or little role for surgery in these patients. Tyrosine kinase inhibitors (TKIs) and immune-oncological (IOs) therapies, either alone or in combination, are recommended in these patients depending on patient and tumour factors. The sequencing of therapies is critical in RCC because the choice of subsequent line therapy is heavily dependent on the response and duration of the previous treatment. There are additional barriers to RCC treatment in India. Immunotherapy is the cornerstone of treatment in ccRCC, but it is prohibitively expensive and not always reimbursed, effectively putting it out of reach for the vast majority of eligible patients in India. Furthermore, in advanced RCC (particularly the clear cell variety), Indian oncologists consider the disease burden of the patients, which is particularly dependent on the quantum of the disease load, clinical symptoms, and performance status of the patient, before deciding on treatment. There are no India-specific guidelines for clear cell RCC (ccRCC) treatment or the positioning and sequencing of molecules in the management of advanced ccRCC that take these country-specific issues into account. The current consensus article provides expert recommendations and treatment algorithms based on existing clinical evidence, which will be useful to specialists managing advanced ccRCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Consenso , Índia
8.
J Fluoresc ; 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37439921

RESUMO

An anthracene thiazole based Schiff base L was synthesized and employed for fluorescence switch-on detection of maleic acid in aqueous DMSO. The non-fluorescent L (10-5 M) showed an instantaneous and selective fluorescence enhancement at 506 nm upon interaction with maleic acid (10-5 M). Other potential carboxylic acids (10-5 M), such as malic acid, citric acid, acetic acid, cinnamic acid, tartaric acid, succinic acid, fumaric acid, oxalic acid and malonic acid failed to alter the chromo-fluorogenic properties of L. Probe L can be employed to detect maleic acid down to 2.74 × 10-6 M. The probe L showed good linearity from 2.97 to 6.87 µM. Analytical utility of L was examined by detecting maleic acid in various food additives and drosophila larvae.

9.
Phys Rev Lett ; 129(20): 201301, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36462025

RESUMO

Microwave cavities have been deployed to search for bosonic dark matter candidates with masses of a few µeV. However, the sensitivity of these cavity detectors is limited by their volume, and the traditionally employed half-wavelength cavities suffer from a significant volume reduction at higher masses. Axion dark matter experiment (ADMX)-Orpheus mitigates this issue by operating a tunable, dielectrically loaded cavity at a higher-order mode, which allows the detection volume to remain large. The ADMX-Orpheus inaugural run excludes dark photon dark matter with kinetic mixing angle χ>10^{-13} between 65.5 µeV (15.8 GHz) and 69.3 µeV (16.8 GHz), marking the highest-frequency tunable microwave cavity dark matter search to date.

12.
Indian J Med Res ; 156(2): 250-259, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36629184

RESUMO

Background & objectives: Non-communicable diseases (NCDs) are the leading cause of death in India. Although studies have reported a high prevalence of NCD in tribal populations, there are limited data pertaining mortality due to NCDs. Therefore, in this study we estimated the proportion of deaths due to NCDs among 15 yr and older age group in tribal districts in India. Methods: We conducted a community-based survey in 12 districts (one per State) with more than 50 per cent tribal population. Data were collected using a verbal autopsy tool from the family member of the deceased. The estimated sample size was 452 deaths per district. We obtained the list of deaths for the reference period of one year and updated it during the survey. The cause of death was assigned using the International Classification of Diseases-10 classification and analyzed the proportions of causes of death. The age-standardized death rate (ASRD) was also estimated. Results: We surveyed 5292 deaths among those above 15 years of age. Overall, NCDs accounted for 66 per cent of the deaths, followed by infectious diseases (15%) and injuries (11%). Cardiovascular diseases were the leading cause of death in 10 of the 12 sites. In East Garo Hills (18%) and Lunglei (26%), neoplasms were the leading cause of death. ASRD due to NCD ranged from 426 in Kinnaur to 756 per 100,000 in East Garo Hills. Interpretation & conclusions: The findings of this community-based survey suggested that NCDs were the leading cause of death among the tribal populations in India. It is hence suggested that control of NCDs should be one of the public health priorities for tribal districts in India.


Assuntos
Doenças Cardiovasculares , Neoplasias , Doenças não Transmissíveis , Morte Perinatal , Feminino , Humanos , Idoso , Doenças não Transmissíveis/epidemiologia , Doenças Cardiovasculares/epidemiologia , Neoplasias/epidemiologia , Prevalência , Índia/epidemiologia , Causas de Morte
13.
Indian J Med Res ; 156(2): 260-268, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36629185

RESUMO

Background and objectives: Non-communicable diseases (NCDs) are highly prevalent in the tribal populations; however, there are limited data regarding health system preparedness to tackle NCDs among these populations. We estimated the availability of human resources, equipment, drugs, services and knowledge of doctors for NCD management in the selected tribal districts in India. Methods: A cross-sectional survey was conducted in 12 districts (one from each State) with at least 50 per cent tribal population in Andaman and Nicobar Islands, Himachal Pradesh, Madhya Pradesh, Odisha and eight northeastern States. Primary health centres (PHCs), community health centres (CHCs) and district/sub-district hospitals (DHs) were surveyed and data on screening and treatment services, human resources, equipment, drugs and information systems indicators were collected and analysed. The data were presented as proportions. Results: In the present study 177 facilities were surveyed, including 156 PHCs/CHCs and 21 DHs. DHs and the majority (82-96%) of the PHCs/CHCs provided outpatient treatment for diabetes and hypertension. Overall, 97 per cent of PHCs/CHCs had doctors, and 78 per cent had staff nurses. The availability of digital blood pressure monitors ranged from 35 to 43 per cent, and drugs were either not available or inadequate. Among 213 doctors, three-fourths knew the correct criteria for hypertension diagnosis, and a few correctly reported diabetes diagnosis criteria. Interpretation & conclusions: The results of this study suggest that the health system of the studied tribal districts was not adequately prepared to manage NCDs. The key challenges included inadequately trained workforce and a lack of equipment and drugs. It is suggested that capacity building and, procurement and distribution of equipment, drugs and information systems to track NCD patients should be the key focus areas of national programmes.


Assuntos
Diabetes Mellitus , Hipertensão , Doenças não Transmissíveis , Humanos , Doenças não Transmissíveis/epidemiologia , Doenças não Transmissíveis/terapia , Estudos Transversais , Atenção Secundária à Saúde , Atenção Primária à Saúde , Instalações de Saúde , Índia/epidemiologia
15.
Dalton Trans ; 50(22): 7783-7790, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33999062

RESUMO

Selectivity between Am3+ and Cm3+ was investigated after their aqueous complexation with three structurally tailored hydrophilic bis-(1,2,4-triazin-3-yl) ligands followed by their extraction with N,N,N'N'-tetraoctyl diglycolamide (TODGA) dissolved in an ionic liquid (C4mim·Tf2N). The three hydrophilic ligands used were SO3PhBTP, SO3PhBTBP, and SO3PhBTPhen. It was evident from the solvent extraction studies that SO3PhBTP formed a stronger complex with Cm3+ than with Am3+, but SO3PhBTPhen showed better complexation ability for Am3+ than for Cm3+, and SO3PhBTBP showed no selectivity for the two actinide ions. DFT calculations indicated that the coordinating 'N' atoms in BTP were more co-planar in the complex and this co-planarity was higher in the Cm3+ complex as compared to that in Am3+. In the case of BTBP and BTPhen ligands, on the other hand, the co-planarity was more pronounced in the Am3+ complexes. Mayer's bond order calculations of M-N bonds in the complexes also indicated a reversal of the complexation ability of the BTP and BTPhen ligands for Am3+ and Cm3+. Calculations of the complexation energies further supported the higher selectivity of the BTP ligand for Am3+ by -52.0 kJ mol-1, and better selectivity of the BTPhen ligand for Cm3+ by -24.7 kJ mol-1.

16.
Appl Radiat Isot ; 170: 109604, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33550088

RESUMO

An attempt was made in this work to evaluate a simple flat sheet supported liquid membrane technique for the separation of carrier free 90Y from 90Sr using two diglycolamide carrier ligands, (i) N,N,N',N'-tetra-n-octyl-diglycolamide (TODGA), and (ii) N,N,N',N'-tetra-(2-ethylhexyl)-diglycolamide (TEHDGA). Various experimental parameters were optimized to get selective transport of 90Y over 90Sr. At 6 M HNO3 feed acidity, >95% 90Y could be recovered selectively in just 4 h with both the ligands. Under identical experimental conditions, about 0.1% transport of Sr was also recorded which could be completely removed by passing through a Sr selective column to get medical grade 90Y pure product. A mathematical model equation was also derived and experimentally validated for predicting the transport of 90Y through membrane.

17.
Phys Rev Lett ; 127(26): 261803, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35029490

RESUMO

We report the results from a haloscope search for axion dark matter in the 3.3-4.2 µeV mass range. This search excludes the axion-photon coupling predicted by one of the benchmark models of "invisible" axion dark matter, the Kim-Shifman-Vainshtein-Zakharov model. This sensitivity is achieved using a large-volume cavity, a superconducting magnet, an ultra low noise Josephson parametric amplifier, and sub-Kelvin temperatures. The validity of our detection procedure is ensured by injecting and detecting blind synthetic axion signals.

19.
Sci Rep ; 9(1): 13704, 2019 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-31548652

RESUMO

Monitoring of anti-malarial drug resistance is vital in Northeast India as this region shares its international border with Southeast Asia. Genetic diversity of Plasmodium parasites regulates transmission dynamics, disease severity and vaccine efficacy. P. falciparum chloroquine resistance transporter (Pfcrt), multidrug resistance-1 (Pfmdr-1) and kelch 13 propeller (PfK-13) genes which govern antimalarial drug resistance and three genetic diversity markers, merozoite surface protein 1 and 2 (Pfmsp-1, Pfmsp-2) and glutamate rich protein (Pfglurp) were evaluated from Tripura, Northeast India using molecular tools. In the Pfcrt gene, 87% isolates showed triple mutations at codons M74I, N75E and K76T. 12.5% isolates in Pfmdr-1 gene showed mutation at N86Y. No polymorphism in PfK-13 propeller was found. Polyclonal infections were observed in 53.85% isolates and more commonly in adults (p = 0.0494). In the Pfmsp-1 locus, the K1 allelic family was predominant (71.2%) followed by the 3D7/IC family (69.2%) in the Pfmsp-2 locus. RII region of Pfglurp exhibited nine alleles with expected heterozygosity of 0.85. The multiplicity of infection for Pfmsp-1, Pfmsp-2 and Pfglurp were 1.56, 1.31 and 1.06 respectively. Overall, the study demonstrated a high level of chloroquine resistance and extensive parasite diversity in the region, necessitating regular surveillance in this population group.


Assuntos
Antimaláricos/farmacologia , Resistência a Medicamentos/genética , Mutação , Plasmodium falciparum/genética , Cloroquina/farmacologia , Variação Genética , Índia , Malária Falciparum/parasitologia , Plasmodium falciparum/efeitos dos fármacos
20.
Lung India ; 36(Supplement): S1-S35, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31006703

RESUMO

Although a simple and useful pulmonary function test, spirometry remains underutilized in India. The Indian Chest Society and National College of Chest Physicians (India) jointly supported an expert group to provide recommendations for spirometry in India. Based on a scientific grading of available published evidence, as well as other international recommendations, we propose a consensus statement for planning, performing and interpreting spirometry in a systematic manner across all levels of healthcare in India. We stress the use of standard equipment, and the need for quality control, to optimize testing. Important technical requirements for patient selection, and proper conduct of the vital capacity maneuver, are outlined. A brief algorithm to interpret and report spirometric data using minimal and most important variables is presented. The use of statistically valid lower limits of normality during interpretation is emphasized, and a listing of Indian reference equations is provided for this purpose. Other important issues such as peak expiratory flow, bronchodilator reversibility testing, and technician training are also discussed. We hope that this document will improve use of spirometry in a standardized fashion across diverse settings in India.

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