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1.
Dalton Trans ; 53(13): 5871-5880, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38415375

RESUMEN

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.

2.
Anaesthesia ; 79(6): 611-626, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38153304

RESUMEN

Despite the existence of evidence-based guidelines for the assessment and management of pain in the critical care setting, the prevalence of acute pain remains high. Inadequate pain management is associated with longer duration of mechanical ventilation, reduced capacity for rehabilitation and long-term psychological sequelae. This study aimed to describe the experiences of pain management from healthcare professionals working in intensive care units. Healthcare professionals were recruited from intensive care units in London, UK using a purposive sampling technique. Semi-structured interviews were transcribed verbatim. Transcripts were analysed using an inductive thematic analysis technique. Thirty participants were recruited from eight diverse intensive care units. Five themes were identified. First, there was a lack of consensus in pain assessment in the ICU where nursing staff described more knowledge and confidence of validated pain measures than physicians, and concerns over validity and usability were raised. Second, there was a universal perception of resource availability impacting the quality of pain management including high clinical workload, staff turnover and availability of certain pain management techniques. Third, acknowledgement of the importance of pain management was highest in those with experience of interacting with critical care survivors. Fourth, participants described their own emotional reaction to managing those in pain which influenced their learning. Finally, there was a perception that, due to the complexity of the intensive care unit population, pain was de-prioritised and there were conflicting views as to whether standardised analgosedation algorithms were useful. This study provides evidence to suggest interdisciplinary training, collaboratively designed decision-making tools, prioritisation initiatives and research priorities are areas that could be targeted to improve pain management in critical care.


Asunto(s)
Personal de Salud , Unidades de Cuidados Intensivos , Manejo del Dolor , Investigación Cualitativa , Humanos , Manejo del Dolor/métodos , Masculino , Femenino , Adulto , Personal de Salud/psicología , Persona de Mediana Edad , Actitud del Personal de Salud , Cuidados Críticos/métodos , Dimensión del Dolor/métodos
3.
Neurol Perspect ; 3(2)2023.
Artículo en Inglés | MEDLINE | ID: mdl-37273896

RESUMEN

Introduction: Informal caregivers of children and adolescents with intellectual disabilities and attention deficit/hyperactivity disorder (ADHD) face numerous challenges. However, no study has yet compared the HRQoL of the caregivers of children and adolescents with these two conditions. We aimed to compare the HRQoL and perceived stress of caregivers of children and adolescents with intellectual disabilities and ADHD. Methods: The HRQoL and perceived stress of informal caregivers of children and adolescents with intellectual disabilities and ADHD (40 in each group) were compared using the perceived stress scale and the Quality of Life Enjoyment and Satisfaction Questionnaire - Short Form, respectively. Results: HRQoL was significantly worse in most dimensions in caregivers of children and adolescents with severe ADHD than in caregivers of children and adolescents with severe intellectual disabilities. However, perceived stress was similar. Conclusion: Differences in the impact of intellectual disability and ADHD on family members' HRQoL should be considered while developing educational programs for patients and their families.

4.
J Phys Condens Matter ; 34(3)2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34592722

RESUMEN

In the present work, we demonstrate that C-doped Zr5Pt3is an electron-phonon superconductor (with critical temperatureTC= 3.8 K) with a nonsymmorphic topological Dirac nodal-line semimetal state, which we report here for the first time. The superconducting properties of Zr5Pt3C0.5have been investigated by means of magnetization, resistivity, specific heat, and muon spin rotation and relaxation (µSR) measurements. We find that at low temperatures, the depolarization rate is almost constant and it can be well described by a single-bands-wave model with a superconducting gap of 2Δ(0)/kBTC= 3.84, somewhat higher than the value of BCS theory. From the transverse field µSR analysis, we estimate the London penetration depthλL= 469 nm, superconducting carrier densityns= 1.83 × 1026 m-3, and effective massm* = 1.428me. The zero field µSR confirms the absence of any spontaneous magnetic field in the superconducting ground state. In order to gain additional insights into the electronic ground state of C-doped Zr5Pt3, we also performed first-principles calculations within the framework of density functional theory (DFT). The observed homogenous electronic character of the Fermi surface as well as the mutual decrease ofTCand density of states at the Fermi level are consistent with the experimental findings of this study. However, the band structure reveals the presence of robust, gapless fourfold-degenerate nodal lines protected by 63screw rotations and glide mirror planes. Therefore, Zr5Pt3represents a novel, unprecedented condensed matter system to investigate the intricate interplay between superconductivity and topology.

5.
Phys Rev Lett ; 126(21): 217202, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-34114835

RESUMEN

CeIrSn with a quasikagome Ce lattice in the hexagonal basal plane is a strongly valence fluctuating compound, as we confirm by hard x-ray photoelectron spectroscopy and inelastic neutron scattering, with a high Kondo temperature of T_{K}∼480 K. We report a negative in-plane thermal expansion α/T below 2 K, which passes through a broad minimum near 0.75 K. Volume and a-axis magnetostriction for B∥a are markedly negative at low fields and change sign before a sharp metamagnetic anomaly at 6 T. These behaviors are unexpected for Ce-based intermediate valence systems, which should feature positive expansivity. Rather they point towards antiferromagnetic correlations at very low temperatures. This is supported by muon spin relaxation measurements down to 0.1 K, which provide microscopic evidence for a broad distribution of internal magnetic fields. Comparison with isostructural CeRhSn suggests that these antiferromagnetic correlations emerging at T≪T_{K} result from geometrical frustration.

6.
J Hazard Mater ; 397: 122476, 2020 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-32416382

RESUMEN

In view of the limited solvent system known for the Sr2+ extraction from acidic media, extraction and recovery of 90Sr from acidic medium using novel Octabenzyloxyoctakis[[[(N,N-diethylamino)carbonyl)]methyl]oxy]calix[8]arene (BOC8A) extractant in nitro alkane medium are presented in this paper. BOC8A and nitro alkanes have been synthesized and characterized by 1H NMR, 13C NMR, FTIR and GC-MS techniques. Solvent composition of 0.01 M BOC8A in nitro octane (NO) has been optimized for substantial amount of extraction of strontium from feed acidity of 3.5-4 M nitric acid, (D3.5-4 M HNO3 = 7.1-7.8). Poor extraction of Pu4+, Ba2+, Na+ and UO22+ and negligible extraction of Am3+, Cs+, Ru3+, Nd3+, Zr2+ and trivalent lanthanides are observed. Ion dissociation mechanism was found to be operative involving an extractable complex having Sr2+, BOC8A and HNO3 in a ratio of 1:1:2. About 99 % of Sr2+ from the loaded solvent was recovered with 0.01 M HNO3. DFT calculations were used to predict the structures of free, protonated BOC8A and its complex with Sr2+. DFT result showed reorientation in conformation of BOC8A due to protonation resulting in the Sr2+ extraction from acidic medium with significantly high interaction energy between Sr2+ and diprotonated form of BOC8A.

7.
Diabet Med ; 37(4): 593-601, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32012347

RESUMEN

In 2008, the US Food and Drug Administration provided guidance for the evaluation of the cardiovascular safety of antidiabetes drugs. The newer antidiabetes drugs, approved after 2008, were therefore evaluated in long-term cardiovascular outcome trials, designed and powered for the assessment of cardiovascular safety. Accordingly, the primary endpoint of these trials was a cardiac composite endpoint. Since 2008, the data from various cardiovascular outcome trials have been reported, including SAVOR-TIMI 53 (saxagliptin), EXAMINE (alogliptin), TECOS (sitagliptin), CARMELINA (linagliptin), CAROLINA (linagliptin), ELIXA (lixisenatide), LEADER (liraglutide), EXSCEL (exenatide once-weekly), SUSTAIN-6 (injectable semaglutide), HARMONY Outcomes (albiglutide), REWIND (dulaglutide), PIONEER-6 (oral semaglutide), EMPA-REG OUTCOME (empagliflozin), the CANVAS Program (canagliflozin) and DECLARE-TIMI 53 (dapagliflozin). Some of these trials subsequently also published data on renal outcomes, although these were secondary or exploratory analyses. Dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 receptor agonists had beneficial effects on albuminuria, while sodium-glucose co-transporter-2 inhibitors additionally showed a positive effect on 'hard' renal outcomes. In contrast to the cardiovascular outcome trials, the renal outcome trial of canagliflozin, CREDENCE, assessed a hard renal endpoint as its primary endpoint and showed positive effects on these hard renal outcomes. In this review, we aim to highlight the renal outcome data from the cardiovascular outcome trials and the CREDENCE trial and understand the differences between their results. The post CREDENCE era would appear to reinforce the position of sodium-glucose co-transporter-2 inhibitors as drugs providing cardiorenal protection, in addition to their anti-glycaemic effects.


Asunto(s)
Diabetes Mellitus/tratamiento farmacológico , Drogas en Investigación/uso terapéutico , Hipoglucemiantes/uso terapéutico , Riñón/efectos de los fármacos , Sistema Cardiovascular/efectos de los fármacos , Sistema Cardiovascular/fisiopatología , Citoprotección/efectos de los fármacos , Diabetes Mellitus/epidemiología , Diabetes Mellitus/fisiopatología , Angiopatías Diabéticas/epidemiología , Angiopatías Diabéticas/prevención & control , Nefropatías Diabéticas/epidemiología , Nefropatías Diabéticas/prevención & control , Humanos , Hipoglucemiantes/clasificación , Riñón/fisiología , Resultado del Tratamiento
9.
J Phys Condens Matter ; 32(6): 065602, 2020 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-31509814

RESUMEN

The superconducting properties of rhombohedral LaIr3 were examined using susceptibility, resistivity, heat capacity, and zero-field (ZF) and transverse-field (TF) muon spin relaxation and rotation ([Formula: see text]SR) measurements. The susceptibility and resistivity measurements confirm a superconducting transition below [Formula: see text] K. Two successive transitions are observed in the heat capacity data, one at [Formula: see text] K and a second at 1.2 K below [Formula: see text]. The heat capacity jump is [Formula: see text], which is lower than 1.43 expected for Bardeen-Cooper-Schrieffer (BCS) weak-coupling limit. TF-[Formula: see text]SR measurements reveal a fully gapped s-wave superconductivity with [Formula: see text], which is small compared to the BCS value of 3.56, suggesting weak-coupling superconductivity. The magnetic penetration depth, [Formula: see text], estimated from TF-[Formula: see text]SR gives [Formula: see text] nm, a superconducting carrier density [Formula: see text] carriers m-3 and a carrier effective-mass enhancement factor [Formula: see text]. ZF-[Formula: see text]SR data show no evidence for any spontaneous magnetic fields below [Formula: see text], which demonstrates that time-reversal symmetry is preserved in the superconducting state of LaIr3.

10.
J Phys Condens Matter ; 32(8): 085601, 2020 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-31689696

RESUMEN

We have investigated the superconducting state of HfIrSi using magnetization, specific heat, muon spin rotation and relaxation ([Formula: see text]SR) measurements. Superconductivity was observed at [Formula: see text] K in both specific heat and magnetization measurements. From an analysis of the transverse-field [Formula: see text]SR data, it is clear that the temperature variation of superfluid density is well fitted by an isotropic Bardeen-Cooper-Schrieffer (BCS) type s-wave gap structure. The superconducting carrier density [Formula: see text] m-3, the magnetic penetration depth, [Formula: see text] nm, and the effective mass, [Formula: see text], were calculated from the TF-[Formula: see text]SR data. Zero-field [Formula: see text]SR data for HfIrSi reveal the absence of any spontaneous magnetic moments below [Formula: see text], indicating that time-reversal symmetry (TRS) is preserved in the superconducting state of HfIrSi. Theoretical investigations suggest that the Hf and Ir atoms hybridize strongly along the c-axis, and that this is responsible for the strong three-dimensionality of this system which screens the Coulomb interaction. As a result, despite the presence of d-electrons in HfIrSi, these correlation effects are weakened, making the electron-phonon coupling more important.

11.
Phys Rev Lett ; 122(14): 147001, 2019 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-31050469

RESUMEN

The newly discovered noncentrosymmetric superconductor ThCoC_{2} exhibits numerous types of unconventional behavior in the field dependent heat capacity data. Here we present the first measurement of the gap symmetry of ThCoC_{2} by muon spin rotation and relaxation (µSR) measurements. The temperature dependence of the magnetic penetration depth measured using the transverse field µSR experiment reveals the evidence of a nodal pairing symmetry. To understand this finding, we carry out calculations of the superconducting pairing eigenvalue and eigenfunction (pairing symmetry) due to the spin-fluctuation mechanism by directly implementing the ab initio band structures. We find that the system possesses a single Fermi surface with considerable three dimensionality and a strong nesting along the k_{z} direction. Such nesting promotes a superconducting state with a cosk_{z}-like pairing symmetry with a prominent nodal line on the k_{z}=±π/2 plane. The result agrees well with the experimental data.

12.
J Phys Condens Matter ; 31(16): 165801, 2019 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-30681979

RESUMEN

We report the zero-field and longitudinal field muon spin relaxation studies in a spin-chain compound Sm2BaNiO5. Two magnetic transitions, that have not been previously detected by the heat capacity and magnetization measurements, are confirmed at 46 and 9 K. The antiferromagnetic order is suggested at 46 K. Analysis of the muon spin polarization unveils the spin-glass transition at 9 K. Time-field scaling relation of the muon spin polarization verifies the spin-spin autocorrelation function following the cut-off power law, which is approximated by the Ogielski form, as employed numerically for characterizing the spin-glasses.

13.
Eur J Neurol ; 26(2): 313-e19, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30266037

RESUMEN

BACKGROUND AND PURPOSE: Data from randomly controlled trials have indicated that a decompressive hemicraniectomy is more clinically effective than medical treatment in the management of space-occupying brain oedema post middle cerebral artery infarction. This economic evaluation compares the impact of the two options in the UK. No recent study has conducted an economic evaluation on this topic for the UK. METHOD: A cost-utility analysis over a time period of 1 year was used, measuring benefits in terms of quality adjusted life years (QALYs) and costs in pound sterling, discounted to 2015 prices. The evaluation was from the perspective of the National Health Service, the largest healthcare provider in the UK. RESULTS: The cost-utility analysis found an incremental cost effectiveness of £116 595.10 for every QALY gained if patients were offered a decompressive hemicraniectomy compared to the best medical treatment. DISCUSSION: This is above the National Institute for Health and Care Excellence (NICE) 'cost-effective' threshold of £20 000-£30 000 per QALY, but lower mortality rates associated with the surgical alternative raises ethical considerations for healthcare providers in the UK.


Asunto(s)
Edema Encefálico/cirugía , Craneotomía/economía , Infarto de la Arteria Cerebral Media/cirugía , Análisis Costo-Beneficio , Craneotomía/métodos , Femenino , Humanos , Masculino , Años de Vida Ajustados por Calidad de Vida , Resultado del Tratamiento
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 207: 354-362, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30292112

RESUMEN

The assessment of cucurbituril (CBn) for selective removal of actinides from nuclear waste streams requires comprehensive understanding of binding parameters and coordination of these complexes. The present work is the first experimental report on complexation of actinide ion with Cucurbit[5]uril (CB5) in solution. The thermodynamic parameters (ΔG, ΔH and ΔS) for complexation of CB5 with U(VI) in formic acid water medium were determined using microcalorimetry and UV-Vis spectroscopy. The enthalpy and entropy of complexation revealed the partial binding of U(VI) to CB5 portal. The partial binding was confirmed by spectroscopic techniques viz. extended X absorption fine structure spectroscopy (EXAFS), 1H and 13C NMR. The EXAFS χ(r) versus r spectra for U-CB5 complex has been fitted from 1.4 to 3.5 Šwith two oxygen shells and a carbon shell. The presence of three carbon atom in secondary shell shows the involvement of only three carbonyl oxygens directly bonding to U(VI) which is in contrast to that calculated from gas phase DFT calculation of unhydrated system. The combined effect of hydration and formic acid encapsulation led to the enhanced stability of partially bound U(VI) to CB5. In the present work the binding of formic acid has also been studied by fluorescence spectroscopy. ESI-MS data shows the unusual stabilization of U(VI) by CB5 in gas phase.

15.
J Phys Condens Matter ; 30(43): 435803, 2018 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-30229750

RESUMEN

The magnetic structure of the ternary equiatomic intermetallic compound PrCuSi is investigated using neutron powder diffraction experiments in 0 T as well as in external magnetic fields up to 2 T. The PrCuSi compound crystallizes in the hexagonal Ni2In-type structure, in the space group P63/mmc. In this structure, cationic ordering of Cu and Si takes place. The antiferromagnetic phase transition in the Pr sublattice takes place at [Formula: see text] K in 0 T. Under an external magnetic field of 2 T, a field-induced ferromagnetic phase is observed. Magnetoelastic coupling is evidenced by an increase in the unit cell volume. Clear signatures of a mixed antiferromagnetic and ferromagnetic phase in weak, intermediate fields, 0.4-0.8 T, are obtained from the present study. Using the present set of experimental data, we construct the H - T phase diagram of PrCuSi.

16.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e957-e963, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29352493

RESUMEN

Two hundred turkey breeder hens and 24 viable toms of 30-35 weeks age of small white variety were distributed into two treatment groups having four replicates of 25 hens and three toms in each treatment. First four replicates were offered a turkey breeder diet (Diet A) (Nutrient requirements of poultry, 1994, National Academic Press, Washington, DC) and the rest four replicates were maintained on a higher plane of nutrition (Diet B) for 8-week duration. After 6 weeks of experimental feeding, two replicates from each treatment groups were vaccinated with ND (R2 B) vaccine. Yolk sac of embryo from birds fed Diet B had a significantly higher (p < .05) IgG, IgM level and HI titre (log 2) than those fed Diet A. HI titre values of embryonic yolk sac from the vaccinated birds fed Diet B were significantly higher (p < .05) than that of the control groups. In addition, HI titre values were significantly higher (p < .05) in the day-old poults of the birds fed Diet B than that of those fed Diet A. There was significantly (p < .01) positive correlation between serum IgG and IgM of the breeder birds and day-old chicks. Similarly, there was significantly (p < .05) positive correlation between yolk IgG and IgM after 1-month experimental feeding and yolk sac IgG and IgM. Positive correlation (p < .05) also existed between yolk sac IgM and day-old chick serum IgM. Furthermore, the HI titres of breeder birds' serum at 14 days post-vaccination were positively correlated with their egg yolk after 10 and 15 days post-vaccination, yolk sac and day-old chicks. Thus, the study envisaged that a higher immunity in neonate poults from turkey breeders maintained on a higher plane of nutrition may be elicited as there was maternal transfer of antibodies from the serum of breeder birds to their offsprings through their yolk sac.


Asunto(s)
Alimentación Animal/análisis , Dieta/veterinaria , Yema de Huevo/química , Inmunoglobulinas/química , Pavos , Saco Vitelino/química , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Femenino , Inmunoglobulinas/metabolismo , Masculino , Necesidades Nutricionales
17.
J Mol Graph Model ; 79: 149-156, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29169059

RESUMEN

The structural stability and electronic properties of pristine and Ga substituted germanane nanosheet were investigated using the density functional theory technique. The stability of bare and Ga substituted germanane nanosheet is substantiated with formation energy. The energy band gap opens upon hydrogenation on germanene sheet, which is utilized as a sensor material for the detection of NH3 and H2O molecules. The interaction of ammonia and humidity on germanane nanosheet is explored using the projected density of states, Bader charge transfer, adsorption energy, average energy gap variation, energy gap and electron density. The interaction of H2O and NH3 gas molecules on germanane material is studied in atomistic level. The interaction of humidity on pristine germanane nanosheet and NH3 on Ga substituted germanane nanosheet is found to be more favorable. The findings recommend that germanane nanosheet can be utilized as a chemi-resistor for the detection of humidity and trace levels of ammonia gas in the environment.


Asunto(s)
Amoníaco/química , Teoría Funcional de la Densidad , Humedad , Nanoestructuras/química , Adsorción , Estructura Molecular
19.
J Phys Condens Matter ; 29(26): 265602, 2017 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-28555613

RESUMEN

The influence of electron doping on semimetallic SrFBiS2 has been investigated by means of resistivity, zero and transverse - field (ZF/TF) muon spin relaxation/rotation (µSR) experiments. SrFBiS2 is semimetallic in its normal state and small amounts of La doping results in bulk superconductivity at 2.8 K, at ambient pressure. The temperature dependence of the superfluid density as determined by TF-µSR can be best modelled by an isotropic s - wave type superconducting gap. We have estimated the magnetic penetration depth [Formula: see text] nm, superconducting carrier density [Formula: see text] carriers m-3 and effective-mass enhancement m * = 1.558 m e. Additionally, there is no clear sign of the occurrence of spontaneous internal magnetic fields below [Formula: see text], which implies that the superconducting state in this material can not be categorized by the broken time-reversal symmetry which is in agreement with the previous theoretical prediction.

20.
Oncogenesis ; 6(5): e327, 2017 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-28481365

RESUMEN

ß-catenin has two different cellular functions: intercellular adhesion and transcriptional activity. The E3 ubiquitin ligase Siah1 causes ubiquitin-mediated degradation of the cytosolic ß-catenin and therefore, impairs nuclear translocation and oncogenic function of ß-catenin. However, the effect of Siah1 on the cell membrane bound ß-catenin has not been studied. In this study, we identified that the carcinogenic bacterium H. pylori increased ETS2 transcription factor-mediated Siah1 protein expression in gastric cancer cells (GCCs) MKN45, AGS and Kato III. Siah1 protein level was also noticeably higher in gastric adenocarcinoma biopsy samples as compared to non-cancerous gastric epithelia. Siah1 knockdown significantly decreased invasiveness and migration of H. pylori-infected GCCs. Although, Siah1 could not increase degradation of the cytosolic ß-catenin and its nuclear translocation, it enhanced degradation of the membrane-bound ß-catenin in the infected GCCs. This loss of membrane-bound pool of ß-catenin was not associated with the proteasomal degradation of E-cadherin. Thus, this work delineated the role of Siah1 in increasing invasiveness of H. pylori-infected GCCs.

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