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1.
Phys Rev Lett ; 132(14): 142502, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640383

RESUMEN

A precision measurement of the ß^{+} decay of ^{8}B was performed using the Beta-decay Paul Trap to determine the ß-ν angular correlation coefficient a_{ßν}. The experimental results were combined with new ab initio symmetry-adapted no-core shell-model calculations to yield the second-most precise measurement from Gamow-Teller decays, a_{ßν}=-0.3345±0.0019_{stat}±0.0021_{syst}. This value agrees with the standard model value of -1/3 and improves uncertainties in ^{8}B by nearly a factor of 2. By combining results from ^{8}B and ^{8}Li, a tight limit on tensor current coupling to right-handed neutrinos was obtained. A recent global evaluation of all other precision ß decay studies suggested a nonzero value for right-handed neutrino coupling in contradiction with the standard model at just above 3σ. The present results are of comparable sensitivity and do not support this finding.

2.
Phys Rev Lett ; 130(19): 192502, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37243659

RESUMEN

We present the first measurement of the α-ß-ν angular correlation in the Gamow-Teller ß^{+} decay of ^{8}B. This was accomplished using the Beta-decay Paul Trap, expanding on our previous work on the ß^{-} decay of ^{8}Li. The ^{8}B result is consistent with the V-A electroweak interaction of the standard model and, on its own, provides a limit on the exotic right-handed tensor current relative to the axial-vector current of |C_{T}/C_{A}|^{2}<0.013 at the 95.5% confidence level. This represents the first high-precision angular correlation measurements in mirror decays and was made possible through the use of an ion trap. By combining this ^{8}B result with our previous ^{8}Li results, we demonstrate a new pathway for increased precision in searches for exotic currents.

3.
RSC Adv ; 13(19): 13240-13251, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37123999

RESUMEN

Deoxyglucose conjugated nanoparticles with persistent luminescence have shown theragnostic potential. In this study, deoxyglucose-conjugated nano-particles with persistent luminescence properties were synthesized, and their theragnostic potential was evaluated in fibrosarcoma cancer cells and a tumor model. The uptake of nano-formulation was found to be higher in mouse fibrosarcoma (WEHI-164) cells cultured in a medium without glucose. Nanoparticles showed a higher killing ability for cancer cells compared to normal cells. A significant accumulation of nanoparticles to the tumor site in mice was evident by the increased tumor/normal leg ratio, resulting in a significant decrease in tumor volume and weight. Histopathological studies showed a significant decrease in the number of dividing mitotic cells but a greater number of apoptotic/necrotic cells in nanoparticle-treated tumor tissues, which was correlated with a lower magnitude of Ki-67 expression (a proliferation marker). Consequently, our results showed the potential of our nano-formulation for cancer theragnosis.

4.
Phys Rev Lett ; 131(26): 262701, 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38215364

RESUMEN

Nuclear isomer effects are pivotal in understanding nuclear astrophysics, particularly in the rapid neutron-capture process where the population of metastable isomers can alter the radioactive decay paths of nuclei produced during astrophysical events. The ß-decaying isomer ^{128m}Sb was identified as potentially impactful since the ß-decay pathway along the A=128 isobar funnels into this state bypassing the ground state. We report the first direct mass measurements of the ^{128}Sb isomer and ground state using the Canadian Penning Trap mass spectrometer at Argonne National Laboratory. We find mass excesses of -84564.8(25) keV and -84608.8(21) keV, respectively, resulting in an excitation energy for the isomer of 43.9(33) keV. These results provide the first key nuclear data input for understanding the role of ^{128m}Sb in nucleosynthesis, and we show that it will influence the flow of the rapid neutron-capture process.

5.
Phys Rev Lett ; 128(20): 202502, 2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35657880

RESUMEN

The electroweak interaction in the standard model is described by a pure vector-axial-vector structure, though any Lorentz-invariant component could contribute. In this Letter, we present the most precise measurement of tensor currents in the low-energy regime by examining the ß-ν[over ¯] correlation of trapped ^{8}Li ions with the Beta-decay Paul Trap. We find a_{ßν}=-0.3325±0.0013_{stat}±0.0019_{syst} at 1σ for the case of coupling to right-handed neutrinos (C_{T}=-C_{T}^{'}), which is consistent with the standard model prediction.

6.
Sci Rep ; 8(1): 14766, 2018 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-30283083

RESUMEN

Monodispersed Fe3O4 magnetic nanoparticles (MNPs) having size of 7 nm have been prepared from iron oleate and made water dispersible by functionalization for biomedical applications. Three different reactions employing thioglycolic acid, aspartic acid and aminophosphonate were performed on oleic acid coated Fe3O4. In order to achieve a control on particle size, the pristine nanoparticles were heated in presence of ferric oleate which led to increase in size from 7 to 11 nm. Reaction parameters such as rate of heating, reaction temperature and duration of heating have been studied. Shape of particles was found to change from spherical to cuboid. The cuboid shape in turn enhances magneto-crystalline anisotropy (Ku). Heating efficacy of these nanoparticles for hyperthermia was also evaluated for different shapes and sizes. We demonstrate heat generation from these MNPs for hyperthermia application under alternating current (AC) magnetic field and optimized heating efficiency by controlling morphology of particles. We have also studied intra-cellular uptake and localization of nanoparticles and cytotoxicity under AC magnetic field in human breast carcinoma cell line.


Asunto(s)
Neoplasias de la Mama/terapia , Compuestos Férricos/uso terapéutico , Hipertermia Inducida/métodos , Nanopartículas de Magnetita/uso terapéutico , Anisotropía , Neoplasias de la Mama/patología , Femenino , Compuestos Férricos/química , Humanos , Hierro/química , Células MCF-7 , Campos Magnéticos , Nanopartículas de Magnetita/química , Temperatura , Agua/química
7.
Phys Rev Lett ; 120(26): 262702, 2018 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-30004776

RESUMEN

The Canadian Penning Trap mass spectrometer at the Californium Rare Isotope Breeder Upgrade (CARIBU) facility was used to measure the masses of eight neutron-rich isotopes of Nd and Sm. These measurements are the first to push into the region of nuclear masses relevant to the formation of the rare-earth abundance peak at A∼165 by the rapid neutron-capture process. We compare our results with theoretical predictions obtained from "reverse engineering" the mass surface that best reproduces the observed solar abundances in this region through a Markov chain Monte Carlo technique. Our measured masses are consistent with the reverse-engineering predictions for a neutron star merger wind scenario.

8.
Phys Rev Lett ; 120(18): 182502, 2018 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-29775351

RESUMEN

The structure of deformed neutron-rich nuclei in the rare-earth region is of significant interest for both the astrophysics and nuclear structure fields. At present, a complete explanation for the observed peak in the elemental abundances at A∼160 eludes astrophysicists, and models depend on accurate quantities, such as masses, lifetimes, and branching ratios of deformed neutron-rich nuclei in this region. Unusual nuclear structure effects are also observed, such as the unexpectedly low energies of the first 2^{+} levels in some even-even nuclei at N=98. In order to address these issues, mass and ß-decay spectroscopy measurements of the ^{160}Eu_{97} and ^{162}Eu_{99} nuclei were performed at the Californium Rare Isotope Breeder Upgrade radioactive beam facility at Argonne National Laboratory. Evidence for a gap in the single-particle neutron energies at N=98 and for large deformation (ß_{2}∼0.3) is discussed in relation to the unusual phenomena observed at this neutron number.

9.
Phys Rev Lett ; 115(18): 182501, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26565463

RESUMEN

In the standard model, the weak interaction is formulated with a purely vector-axial-vector (V-A) structure. Without restriction on the chirality of the neutrino, the most general limits on tensor currents from nuclear ß decay are dominated by a single measurement of the ß-ν[over ¯] correlation in ^{6}He ß decay dating back over a half century. In the present work, the ß-ν[over ¯]-α correlation in the ß decay of ^{8}Li and subsequent α-particle breakup of the ^{8}Be^{*} daughter was measured. The results are consistent with a purely V-A interaction and in the case of couplings to right-handed neutrinos (C_{T}=-C_{T}^{'}) limits the tensor fraction to |C_{T}/C_{A}|^{2}<0.011 (95.5% C.L.). The measurement confirms the ^{6}He result using a different nuclear system and employing modern ion-trapping techniques subject to different systematic uncertainties.

10.
J Mater Chem B ; 3(27): 5455-5466, 2015 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32262517

RESUMEN

This investigation reports the preparation of agglomerated Fe3O4 nanoparticles and evaluation of its utility as a viable carrier in the preparation of radiolanthanides as potential therapeutic agents for the treatment of arthritis. The material was synthesized by a chemical route and characterized by XRD, FT-IR, SEM, EDX and TEM analysis. The surface of agglomerated particle possessed ion pairs (-O-:Na+) after dispersing particles in a NaHCO3 solution at pH = 7 which is conducive for radiolanthanide (*Ln = 90Y, 153Sm, 166Ho, 169Er, 177Lu) loading by replacement of Na+ ions with tripositive radiolanthanide ions. Radiolanthanide-loaded particulates exhibited excellent in vitro stability up to ∼3 half-lives of the respective lanthanide radionuclides when stored in normal saline at 37 °C. The radiochemical purities of the loaded particulates were found to be retained to the extent of >70% after 48 h of storage when challenged by a strong chelator DTPA present at a concentration as high as 5 mM, indicating fairly strong chemical association of lanthanides with agglomerated Fe3O4 nanoparticles. Biodistribution studies of 90Y and 166Ho-loaded particulates carried out after intra-articular injection into one of the knee joints of a normal Wistar rat revealed near-complete retention of the radioactive preparations (>98% of the administered radioactivity) within the joint cavity even after 72 h post injection. This was further confirmed by sequential whole-body radio-luminescence imaging. These experimental results are indicative of the potential use of radiolanthanide-loaded agglomerated Fe3O4 nanoparticles for the treatment of arthritis.

12.
Phys Rev Lett ; 111(6): 061102, 2013 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-23971550

RESUMEN

The Canadian Penning Trap mass spectrometer has made mass measurements of 33 neutron-rich nuclides provided by the new Californium Rare Isotope Breeder Upgrade facility at Argonne National Laboratory. The studied region includes the 132Sn double shell closure and ranges in Z from In to Cs, with Sn isotopes measured out to A=135, and the typical measurement precision is at the 100 ppb level or better. The region encompasses a possible major waiting point of the astrophysical r process, and the impact of the masses on the r process is shown through a series of simulations. These first-ever simulations with direct mass information on this waiting point show significant increases in waiting time at Sn and Sb in comparison with commonly used mass models, demonstrating the inadequacy of existing models for accurate r-process calculations.

13.
Eplasty ; 13: e18, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23641297

RESUMEN

OBJECTIVES: Otophyma is a rare condition that can present as the end stage of any chronic inflammatory disease affecting the ear such as rosacea, eczema, or otitis externa. It can result in conductive hearing loss, low self-esteem, and social embarrassment. This report highlights a case of otophyma treated successfully using a full-thickness skin graft. METHODS: We present a case of a 41-year-old lady referred to our department with a 23-year history of bilateral otophyma. During this time, her hearing progressively diminished as the swelling occluded her external auditory meatus. She had been unsuccessfully managed for years with topical emollients, steroids, and regular ear toileting. RESULT: She was treated by excision of the phymatous tissue and full-thickness grafting, which resulted in a patent external auditory meatus and an improvement in her hearing. CONCLUSIONS: The use of a full-thickness skin graft is one of the many treatment options available for the treatment of otophyma. We present a literature review on this uncommon condition and a discussion on the various treatment options available to the patient.

14.
J Plast Reconstr Aesthet Surg ; 66(7): 968-72, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23571016

RESUMEN

BACKGROUND: Space of Parona Infection is a rare and potentially limb threatening complication of pyogenic flexor tenosynovitis. The aim of this study is to review the presentation, management and outcomes of space of Parona infections in our institution. METHOD: This was a retrospective study. Data was collected from patients with confirmed space of Parona infections determined by the presence of pus in this space during the initial surgical debridement; between 2009 and 2011. The following parameters were analysed: patient demographics, presentation, microbiological findings and surgical management. The outcomes assessed included the final active range of motion of the primary affected finger, rate of amputation and duration of hospital stay and follow up. RESULTS: There were nine confirmed space of Parona infections. 7/9 patients reported a history of trauma. The thumb (7/9) followed by the little finger (2/9) were primarily involved in all cases. Seven patients presented with symptoms of acute median nerve compression in addition to forearm tenderness. Patients had a mean of two (range; 1-5) visits to theatre for washout and debridement. Positive swabs were present in 8/9 cases, of which five patients cultured ß haemolytic streptococci. Average hospital stay was six days (range; 3-12) and final active range of movement of the affected finger ranged from 0 to 95%. CONCLUSION: Involvement of space of Parona should be suspected in patients with flexor tendon sheath infections of the thumb or little finger. Early antimicrobial therapy directed particularly at ß haemolytic streptococcus combined with prompt surgical debridement and physiotherapy are critical to optimal functional outcome.


Asunto(s)
Mano , Infecciones Estreptocócicas/terapia , Tenosinovitis/microbiología , Tenosinovitis/terapia , Antibacterianos/uso terapéutico , Estudios de Cohortes , Terapia Combinada , Drenaje/métodos , Femenino , Estudios de Seguimiento , Antebrazo/microbiología , Antebrazo/fisiopatología , Humanos , Masculino , Modalidades de Fisioterapia , Cuidados Posoperatorios/métodos , Recuperación de la Función , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Infecciones Estreptocócicas/diagnóstico , Tenosinovitis/diagnóstico , Irrigación Terapéutica/métodos , Resultado del Tratamiento
15.
Phys Rev Lett ; 110(9): 092501, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23496704

RESUMEN

A novel technique for ß-delayed neutron spectroscopy has been demonstrated using trapped ions. The neutron-energy spectrum is reconstructed by measuring the time of flight of the nuclear recoil following neutron emission, thereby avoiding all the challenges associated with neutron detection, such as backgrounds from scattered neutrons and γ rays and complicated detector-response functions. (137)I(+) ions delivered from a (252)Cf source were confined in a linear Paul trap surrounded by radiation detectors, and the ß-delayed neutron-energy spectrum and branching ratio were determined by detecting the ß(-) and recoil ions in coincidence. Systematic effects were explored by determining the branching ratio three ways. Improvements to achieve higher detection efficiency, better energy resolution, and a lower neutron-energy threshold are proposed.

16.
Phys Rev Lett ; 110(9): 092502, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23496705

RESUMEN

A measurement of the α-ß-ν[over ¯] angular correlation in the Gamow-Teller decay (8)Li→(8)Be(*)+ν[over ¯]+ß, (8)Be(*)→α+α has been performed using ions confined in a linear Paul trap surrounded by silicon detectors. The energy difference spectrum of the α particles emitted along and opposite the direction of the ß particle is consistent with the standard model prediction and places a limit of 3.1% (95.5% confidence level) on any tensor contribution to the decay. From this result, the amplitude of any tensor component C(T) relative to that of the dominant axial-vector component C(A) of the electroweak interaction is limited to |C(T)/C(A)|<0.18 (95.5% confidence level). This experimental approach is facilitated by several favorable features of the (8)Li ß decay and has different systematic effects than the previous ß-ν[over ¯] correlation results for a pure Gamow-Teller transition obtained from studying (6)He ß decay.

17.
Case Rep Surg ; 2013: 765279, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23401838

RESUMEN

We present the first reported case of the prophylactic use of lipid emulsion therapy in the removal of an extensive, circumferential malignant melanoma in a morbidly obese patient, under local anaesthetic. The advantages of this technique allowed the patient to avoid intraoperative invasive monitoring and postoperative critical care admission and assisted during the operation by rotating her leg when needed. This is a useful technique that can be employed in urgent cases where there is a need to excise extensive skin malignancies in patients who are unsuitable for general or regional anaesthesia.

18.
Indian J Exp Biol ; 48(10): 1002-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21299043

RESUMEN

Dielectric constant and loss factor of Raj-4120 variety of Indian wheat were determined in powder form (grain size 125 to 150 micron) at room temperature. Microwaves at three different frequencies were employed in C-band, X-band and Ku-band respectively for investigating frequency dependence of dielectric parameters of the sample. Bulk dielectric values of the sample were determined by employing the dielectric mixture relations, such as, half power mixture equation, Landau and Lifshitz, Looyenga equation etc.


Asunto(s)
Análisis de los Alimentos/métodos , Triticum/química , Espectroscopía Dieléctrica , India , Microondas , Polvos
19.
Phys Rev Lett ; 95(10): 102501, 2005 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-16196923

RESUMEN

The masses of the radioactive nuclei (46)V and its decay daughter (46)Ti have been measured with the Canadian Penning Trap on-line Penning trap mass spectrometer to a precision of 1 x 10(-8). A Q(EC) value of 7052.90(40) keV for the superallowed beta decay of (46)V is obtained from the difference of these two masses. With this precise Q value, the Ft value for this decay is determined with improved precision. An investigation of an earlier Q-value measurement for (46)V uncovers a set of 7 measurements that cannot be reconciled with modern data and affects previous evaluations of V(ud) from superallowed Fermi decays. A new evaluation, adding our new data and removing the discredited subset, yields new values for G(V) and V(ud). When combined with recent results for V(us), this yields modified constraints for the unitarity of the Cabibbo-Kobayashi-Maskawa matrix and other extensions of the standard model.

20.
Palliat Med ; 18(3): 177-83, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15198130

RESUMEN

Breakthrough pain (BKP) is a transitory flare of pain that occurs on a background of relatively well controlled baseline pain. Previous surveys have found that BKP is highly prevalent among patients with cancer pain and predicts more severe pain, pain-related distress and functional impairment, and relatively poor quality of life. An international group of investigators assembled by a task force of the International Association for the Study of Pain (IASP) evaluated the prevalence and characteristics of BKP as part of a prospective, cross-sectional survey of cancer pain. Fifty-eight clinicians in 24 countries evaluated a total of 1095 patients with cancer pain using patient-rated items from the Brief Pain Inventory (BPI) and observer-rated measures. The observer-rated information included demographic and tumor-related data, the occurrence of BKP, and responses on checklists of pain syndromes and pathophysiologies. The clinicians reported BKP in 64.8% of patients. Physicians from English-speaking countries were significantly more likely to report BKP than other physicians. BKP was associated with higher pain scores and functional interference on the BPI. Multivariate analysis showed an independent association of BKP with the presence of more than one pain, a vertebral pain syndrome, pain due to plexopathy, and English-speaking country. These data confirm the high prevalence of BKP, its association with more severe pain and functional impairment, and its relationship to specific cancer pain syndromes. Further studies are needed to characterize subtypes of BKP. The uneven distribution of BKP reporting across pain specialists from different countries suggests that more standardized methods for diagnosing BKP are needed.


Asunto(s)
Neoplasias , Dolor/prevención & control , Análisis de Varianza , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor/clasificación , Dolor/epidemiología , Dimensión del Dolor , Prevalencia , Síndrome
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