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1.
Phys Rev Lett ; 129(17): 172701, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36332266

RESUMO

The ß-delayed one- and two-neutron emission probabilities (P_{1n} and P_{2n}) of 20 neutron-rich nuclei with N≥82 have been measured at the RIBF facility of the RIKEN Nishina Center. P_{1n} of ^{130,131}Ag, ^{133,134}Cd, ^{135,136}In, and ^{138,139}Sn were determined for the first time, and stringent upper limits were placed on P_{2n} for nearly all cases. ß-delayed two-neutron emission (ß2n) was unambiguously identified in ^{133}Cd and ^{135,136}In, and their P_{2n} were measured. Weak ß2n was also detected from ^{137,138}Sn. Our results highlight the effect of the N=82 and Z=50 shell closures on ß-delayed neutron emission probability and provide stringent benchmarks for newly developed macroscopic-microscopic and self-consistent global models with the inclusion of a statistical treatment of neutron and γ emission. The impact of our measurements on r-process nucleosynthesis was studied in a neutron star merger scenario. Our P_{1n} and P_{2n} have a direct impact on the odd-even staggering of the final abundance, improving the agreement between calculated and observed Solar System abundances. The odd isotope fraction of Ba in r-process-enhanced (r-II) stars is also better reproduced using our new data.

2.
Am J Transplant ; 18(3): 696-703, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29087035

RESUMO

Preliminary evidence suggests that postoperative cognitive dysfunction (POCD) is common after lung transplantation. The impact of POCD on clinical outcomes has yet to be studied. The association between POCD and longer-term survival was therefore examined in a pilot study of posttransplantation survivors. Forty-nine participants from a prior randomized clinical trial underwent a neurocognitive assessment battery pretransplantation and 6 months posttransplantation, including assessments of the domains of Executive Function (Trail Making Test, Stroop, Digit Span), Processing Speed (Ruff 2 and 7 Test, Digit Symbol Substitution Test), and Verbal Memory (Verbal Paired Associates, Logical Memory, Animal Naming, and Controlled Oral Word Association Test). During a 13-year follow-up, 33 (67%) participants died. Greater neurocognition was associated with longer survival (hazard ratio [HR] = 0.49 [0.25-0.96], P = .039), and this association was strongest on tests assessing Processing Speed (HR = 0.58 [0.36-0.95], P = .03) and Executive Function (HR = 0.52 [0.28-0.97], P = .040). In addition, unadjusted analyses suggested an association between greater Memory performance and lower risk of CLAD (HR = 0.54 [0.29-1.00], P = .050). Declines in Executive Function tended to be predictive of worse survival. These preliminary findings suggest that postoperative neurocognition is predictive of subsequent mortality among lung transplant recipients. Further research is needed to confirm these findings in a larger sample and to examine mechanisms responsible for this relationship.


Assuntos
Transtornos Cognitivos/mortalidade , Rejeição de Enxerto/mortalidade , Transplante de Pulmão/efeitos adversos , Complicações Pós-Operatórias , Qualidade de Vida , Transtornos Cognitivos/etiologia , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Projetos Piloto , Prognóstico , Fatores de Risco , Taxa de Sobrevida
3.
Am J Transplant ; 16(1): 271-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26366639

RESUMO

Lung transplantation has become an increasingly common treatment for patients with end-stage lung disease. Few studies have examined psychosocial risk factors for mortality in transplant recipients, despite evidence suggesting that elevated levels of negative affect are associated with greater mortality following major cardiac surgery. We therefore examined the relationship between negative affect early after lung transplantation and long-term survival in a sample of 132 lung transplant recipients (28 cystic fibrosis, 64 chronic obstructive pulmonary disease, 26 idiopathic pulmonary fibrosis, 14 other) followed for up to 13.5 years (median 7.4 years) following transplantation. Patients underwent both medical and psychosocial assessments 6 months following transplantation, which included the Beck Depression Inventory-II (BDI-II), Spielberger Anxiety Inventory, and General Health Questionnaire (GHQ). Over the course of follow-up, 80 (61%) participants died. Controlling for demographic factors, native lung disease, disease severity, family income, education level, social support, and frequency of posttransplant rejection, elevated symptoms of depression (BDI-II: HR = 1.31, p = 0.011) and distress (GHQ: HR = 1.28, p = 0.003) were associated with increased mortality. Higher levels of depression and general distress, but not anxiety, measured 6 months following lung transplantation are associated with increased mortality, independent of background characteristics and medical predictors.


Assuntos
Ansiedade/mortalidade , Transtorno Depressivo Maior/mortalidade , Transplante de Pulmão/psicologia , Complicações Pós-Operatórias , Transplantados/psicologia , Ansiedade/diagnóstico , Ansiedade/psicologia , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/psicologia , Feminino , Seguimentos , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
4.
Soft Matter ; 12(20): 4530-6, 2016 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-27094902

RESUMO

Dynamic control of the distribution of polystyrene suspended nanoparticles in evaporating droplets is investigated using a 2.9 µm high power laser. Under laser radiation a droplet is locally heated and fluid flows are induced that overcome the capillary flow, and thus a reversal of the coffee-stain effect is observed. Suspension particles are accumulated in a localised area, one order of magnitude smaller than the original droplet size. By scanning the laser beam over the droplet, particles can be deposited in an arbitrary pattern. This finding raises the possibility for direct laser writing of suspended particles through a liquid layer. Furthermore, a highly uniform coating is possible by manipulating the laser beam diameter and exposure time. The effect is expected to be universally applicable to aqueous solutions independent of solutes (either particles or molecules) and deposited substrates.

5.
BMC Infect Dis ; 16: 30, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26818566

RESUMO

BACKGROUND: Artemether-lumefantrine is currently the most widely recommended treatment of uncomplicated malaria. Lopinavir-based antiretroviral therapy is the commonly recommended second-line HIV treatment. Artemether and lumefantrine are metabolised by cytochrome P450 isoenzyme CYP3A4, which lopinavir/ritonavir inhibits, potentially causing clinically important drug-drug interactions. METHODS: An adaptive, parallel-design safety and pharmacokinetic study was conducted in HIV-infected (malaria-negative) patients: antiretroviral-naïve and those stable on lopinavir/ritonavir-based antiretrovirals. Both groups received the recommended six-dose artemether-lumefantrine treatment. The primary outcome was day-7 lumefantrine concentrations, as these correlate with antimalarial efficacy. Adverse events were solicited throughout the study, recording the onset, duration, severity, and relationship to artemether-lumefantrine. RESULTS: We enrolled 34 patients. Median day-7 lumefantrine concentrations were almost 10-fold higher in the lopinavir than the antiretroviral-naïve group [3170 versus 336 ng/mL; p = 0.0001], with AUC(0-inf) and Cmax increased five-fold [2478 versus 445 µg.h/mL; p = 0.0001], and three-fold [28.2 versus 8.8 µg/mL; p < 0.0001], respectively. Lumefantrine Cmax, and AUC(0-inf) increased significantly with mg/kg dose in the lopinavir, but not the antiretroviral-naïve group. While artemether exposure was similar between groups, Cmax and AUC(0-8h) of its active metabolite dihydroartemisinin were initially two-fold higher in the lopinavir group [p = 0.004 and p = 0.0013, respectively]. However, this difference was no longer apparent after the last artemether-lumefantrine dose. Within 21 days of starting artemether-lumefantrine there were similar numbers of treatment emergent adverse events (42 vs. 35) and adverse reactions (12 vs. 15, p = 0.21) in the lopinavir and antiretroviral-naïve groups, respectively. There were no serious adverse events and no difference in electrocardiographic QTcF- and PR-intervals, at the predicted lumefantrine Tmax. CONCLUSION: Despite substantially higher lumefantrine exposure, intensive monitoring in our relatively small study raised no safety concerns in HIV-infected patients stable on lopinavir-based antiretroviral therapy given the recommended artemether-lumefantrine dosage. Increased day-7 lumefantrine concentrations have been shown previously to reduce the risk of malaria treatment failure, but further evidence in adult patients co-infected with malaria and HIV is needed to assess the artemether-lumefantrine risk : benefit profile in this vulnerable population fully. Our antiretroviral-naïve patients confirmed previous findings that lumefantrine absorption is almost saturated at currently recommended doses, but this dose-limited absorption was overcome in the lopinavir group. TRIAL REGISTRATION: Clinical Trial Registration number NCT00869700. Registered on clinicaltrials.gov 25 March 2009.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/farmacocinética , Artemeter , Artemisininas/efeitos adversos , Artemisininas/farmacocinética , Artemisininas/uso terapêutico , Interações Medicamentosas , Etanolaminas/efeitos adversos , Etanolaminas/farmacocinética , Etanolaminas/uso terapêutico , Feminino , Fluorenos/efeitos adversos , Fluorenos/farmacocinética , Fluorenos/uso terapêutico , Infecções por HIV/metabolismo , HIV-1/efeitos dos fármacos , Humanos , Lopinavir/efeitos adversos , Lopinavir/farmacocinética , Lopinavir/uso terapêutico , Lumefantrina , Masculino , Ritonavir/efeitos adversos , Ritonavir/farmacocinética , Ritonavir/uso terapêutico
6.
Water Resour Res ; 51(7): 5531-5546, 2015 07.
Artigo em Inglês | MEDLINE | ID: mdl-26924859

RESUMO

A generalized framework for discharge uncertainty estimation is presentedAllows estimation of place-specific discharge uncertainties for many catchmentsLocal conditions dominate in determining discharge uncertainty magnitudes.

7.
Cytopathology ; 25(2): 108-11, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23551700

RESUMO

OBJECTIVES: Patients diagnosed with bladder carcinoma in situ (CIS) and treated with intravesical Bacillus Calmette-Guerin (BCG) often undergo post-induction random bladder biopsies to assess treatment response. We sought to determine the correlation between post-induction urinary cytology/cystoscopy and histopathological findings obtained by random bladder biopsies. METHODS: Patients who were treated with BCG between 2006 and 2010 for CIS, had surveillance cystoscopy and cytology, and subsequently underwent random bladder biopsies were selected for analysis. Patients with a history of or concomitant urothelial cell carcinoma (UCC) stage T1 or higher were excluded. Cystoscopic finings were characterized as follows: negative - no mucosal erythema, raised lesions or papillary tumours; suspicious - mucosal erythema, but no raised lesions or papillary tumours; and positive - sessile or papillary tumours. The accuracy of cytology in predicting the results of subsequent random bladder biopsies was analysed. RESULTS: Of 21 patients included, surveillance cystoscopy findings were characterized as negative in nine, suspicious in seven and positive in five. Of 16 patients with negative/suspicious cystoscopy, 13 had agreement between cytology and biopsy, nine of whom were negative and four positive. Three of 16 patients had positive cytology, but negative biopsies; on further investigation of these three, one had CIS and two subsequent UCC. In the positive cystoscopy group, four of five patients had agreement between cytology and biopsy, two of whom were negative and two positive. One of the five patients had negative cytology, but a positive biopsy. CONCLUSION: Our data suggest foregoing random bladder biopsies in patients with negative urine cytology and no evidence of intravesical recurrence on cystoscopy following an induction course of BCG for CIS of the urinary bladder.


Assuntos
Biópsia , Carcinoma in Situ/terapia , Citodiagnóstico/métodos , Bexiga Urinária/patologia , Adulto , Vacina BCG/administração & dosagem , Carcinoma in Situ/patologia , Cistoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia
8.
Science ; 381(6660): 867-872, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37616348

RESUMO

Coronal holes are areas on the Sun with open magnetic field lines. They are a source region of the solar wind, but how the wind emerges from coronal holes is not known. We observed a coronal hole using the Extreme Ultraviolet Imager on the Solar Orbiter spacecraft. We identified jets on scales of a few hundred kilometers, which last 20 to 100 seconds and reach speeds of ~100 kilometers per second. The jets are powered by magnetic reconnection and have kinetic energy in the picoflare range. They are intermittent but widespread within the observed coronal hole. We suggest that such picoflare jets could produce enough high-temperature plasma to sustain the solar wind and that the wind emerges from coronal holes as a highly intermittent outflow at small scales.

9.
Nat Commun ; 14(1): 2107, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055427

RESUMO

Magnetic reconnection is a key mechanism involved in solar eruptions and is also a prime possibility to heat the low corona to millions of degrees. Here, we present ultra-high-resolution extreme ultraviolet observations of persistent null-point reconnection in the corona at a scale of about 390 km over one hour observations of the Extreme-Ultraviolet Imager on board Solar Orbiter spacecraft. The observations show formation of a null-point configuration above a minor positive polarity embedded within a region of dominant negative polarity near a sunspot. The gentle phase of the persistent null-point reconnection is evidenced by sustained point-like high-temperature plasma (about 10 MK) near the null-point and constant outflow blobs not only along the outer spine but also along the fan surface. The blobs appear at a higher frequency than previously observed with an average velocity of about 80 km s-1 and life-times of about 40 s. The null-point reconnection also occurs explosively but only for 4 minutes, its coupling with a mini-filament eruption generates a spiral jet. These results suggest that magnetic reconnection, at previously unresolved scales, proceeds continually in a gentle and/or explosive way to persistently transfer mass and energy to the overlying corona.

10.
Am J Transplant ; 12(9): 2519-25, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22548872

RESUMO

Although neurocognitive impairment is relatively common among patients with advanced lung disease, little is known regarding changes in neurocognition following lung transplantation. We therefore administered 10 tests of neurocognitive functioning before and 6 months following lung transplantation and sought to identify predictors of change. Among the 49 study participants, native diseases included chronic obstructive pulmonary disease (n = 22), cystic fibrosis (n = 12), nonfibrotic diseases (n = 11) and other (n = 4). Although composite measures of executive function and verbal memory scores were generally within normal limits both before and after lung transplantation, verbal memory performance was slightly better posttransplant compared to baseline (p < 0.0001). Executive function scores improved in younger patients but worsened in older patients (p = 0.03). A minority subset of patients (29%) exhibited significant cognitive decline (i.e. >1 standard deviations on at least 20% of tests) from baseline to posttransplant. Patients who declined were older (p < 0.004) and tended to be less educated (p = 0.07). Lung transplantation, like cardiac revascularization procedures, appears to be associated with cognitive decline in a subset of older patients, which could impact daily functioning posttransplant.


Assuntos
Cognição , Pneumopatias/cirurgia , Transplante de Pulmão , Adulto , Feminino , Humanos , Pneumopatias/psicologia , Masculino
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