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1.
Rhinology ; 62(3): 271-286, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38353499

RESUMO

BACKGROUND: The prelacrimal window approach (PLWA) is a minimally invasive surgical technique that has been proposed as an alternative to the traditional approaches to access the maxillary sinus. METHODOLOGY: A systematic review with meta-analysis was performed following PRISMA guidelines and identified 368 articles for initial review of which 14 (610 participants) met the criteria for meta-analysis. Four databases, including PubMed, Google Scholar, Web of Science and Scopus, were searched to identify relevant articles. Two independent reviewers conducted the eligibility assessment for the included studies. Methodology quality and risk of bias were evaluated by New Castle Ottawa scale. The outcomes assessed were recurrence of the pathology, postoperative morbidity including epiphora, dry nose, facial, gingival numbness, epistaxis or local infection. RESULTS: The present data suggest a significant reduction in the recurrence rate of maxillary sinus pathology following PLWA when compared to conventional surgery (endoscopic medial maxillectomy, endoscopic sinus surgery and the Caldwell-Luc operation). The rates of epiphora, facial or gingival numbness, epistaxis or infection requiring intervention, were not significantly different between the procedures. CONCLUSIONS: Maxillary sinus pathology can be effectively treated using the PLWA technique, as it has been shown to result in a lower recurrence rate compared to conventional surgeries.


Assuntos
Seio Maxilar , Humanos , Seio Maxilar/cirurgia , Endoscopia/métodos , Doenças dos Seios Paranasais/cirurgia
2.
Phys Rev Lett ; 130(23): 232301, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37354417

RESUMO

For the first time, the (d,^{2}He) reaction was successfully used in inverse kinematics to extract the Gamow-Teller transition strength in the ß^{+} direction from an unstable nucleus. The new technique was made possible by the use of an active-target time-projection chamber and a magnetic spectrometer, and opens a path to addressing a range of scientific challenges, including in astrophysics and neutrino physics. In this Letter, the nucleus studied was ^{14}O, and the Gamow-Teller transition strength to ^{14}N was extracted up to an excitation energy of 22 MeV. The data were compared to shell-model and state-of-the-art coupled-cluster calculations. Shell-model calculations reproduce the measured Gamow-Teller strength distribution up to about 15 MeV reasonably well, after the application of a phenomenological quenching factor. In a significant step forward to better understand this quenching, the coupled-cluster calculation reproduces the full strength distribution well without such quenching, owing to the large model space, the inclusion of strong correlations, and the coupling of the weak interaction to two nucleons through two-body currents.


Assuntos
Núcleo Celular , Física , Fenômenos Biomecânicos
3.
BMC Vet Res ; 19(1): 222, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875898

RESUMO

Human and veterinary medicine have historically presented many medical areas of potential synergy and convergence. Mechanical osteoarthritis (MOA) is characterized by a gradual complex imbalance between cartilage production, loss, and derangement. Any joint instability that results in an abnormal overload of the joint surface can trigger MOA. As MOA has a prevailing mechanical aetiology, treatment effectiveness can only be accomplished if altered joint mechanics and mechanosensitive pathways are normalized and restored. Otherwise, the inflammatory cascade of osteoarthritis will be initiated, and the changes may become irreversible. The management of the disease using non-steroidal anti-inflammatory drugs, analgesics, physical therapy, diet changes, or nutraceuticals is conservative and less effective. MOA is a determinant factor for the development of hip dysplasia in both humans and dogs. Hip dysplasia is a hereditary disease with a high incidence and, therefore, of great clinical importance due to the associated discomfort and significant functional limitations. Furthermore, on account of analogous human and canine hip dysplasia disease and under the One Medicine concept, unifying veterinary and human research could improve the well-being and health of both species, increasing the acknowledgement of shared diseases. Great success has been accomplished in humans regarding preventive conservative management of hip dysplasia and following One Medicine concept, similar measures would benefit dogs. Moreover, animal models have long been used to better understand the different diseases' mechanisms. Current research in animal models was addressed and the role of rabbit models in pathophysiologic studies and of the dog as a spontaneous animal model were highlighted, denoting the inexistence of rabbit functional models to investigate therapeutic approaches in hip MOA.


Assuntos
Doenças do Cão , Luxação do Quadril , Displasia Pélvica Canina , Instabilidade Articular , Osteoartrite do Quadril , Animais , Humanos , Cães , Coelhos , Osteoartrite do Quadril/terapia , Osteoartrite do Quadril/veterinária , Luxação do Quadril/veterinária , Displasia Pélvica Canina/terapia , Instabilidade Articular/veterinária , Suplementos Nutricionais , Doenças do Cão/terapia
4.
J Endocrinol Invest ; 46(9): 1799-1806, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36780067

RESUMO

INTRODUCTION: Primary hyperparathyroidism (PHPT) caused by parathyroid tumours is mostly sporadic, with a genetic cause identified in 5-10% of cases. Familial parathyroid tumours can be included in complex syndromes, such as multiple endocrine neoplasia (MEN) type 1, 2A and 4 or hyperparathyroidism-jaw tumour syndrome (HPT-JT). OBJECTIVE: Characterisation of the familial parathyroid tumours followed-up at our centre and comparison of the different clinicopathological manifestations between the syndromes. METHODS: Retrospective analysis of 48 patients with familial parathyroid tumours harbouring RET (n = 11), CDC73 (n = 20) and MEN1 (n = 17) germline mutations was performed. RESULTS: Cases of PHPT in MEN2A syndrome presented with lower serum PTH (sPTH) and serum calcium (sCa) levels at diagnosis (sPTH = 108.0 (IQR 53.3) pg/mL, sCa = 10.6 ± 1.1 mg/dL) than MEN1 (sPTH = 196.9 (IQR 210.5) pg/mL, sCa = 11.7 ± 1.2 mg/dL) (p = 0.01, p = 0.03, respectively) or HPT-JT cases (sPTH = 383.5 (IQR 775.8) pg/mL, sCa = 12.9 ± 1.8 mg/dL) (p = 0.01; p < 0.001, respectively). There was a statistical difference in sCa levels between MEN1 and HPT-JT (p = 0.02), but not between sPTH (p = 0.07). The predominant first manifestation of the syndrome in MEN1 was gastroenteropancreatic neuroendocrine tumour (GEP-NET) in 47.1% of the cases, in MEN2A was medullary thyroid cancer (90.9%) and in HPT-JT was PHPT in 85% patients. In MEN1 syndrome, the number of affected parathyroid glands was significantly higher than in MEN2A (p < 0.001) and HPT-JT (p = 0.01). CONCLUSION: The first manifestation of the syndrome in MEN1 cases was GEP-NET and not PHPT. Although presenting at similar ages, patients with MEN2A exhibit less severe biochemical and clinical PHPT at diagnosis than the other familial syndromes.


Assuntos
Neoplasia Endócrina Múltipla Tipo 1 , Neoplasia Endócrina Múltipla Tipo 2a , Neoplasias das Paratireoides , Humanos , Glândulas Paratireoides , Neoplasias das Paratireoides/diagnóstico , Neoplasias das Paratireoides/genética , Neoplasia Endócrina Múltipla Tipo 2a/genética , Síndrome , Estudos Retrospectivos , Neoplasia Endócrina Múltipla Tipo 1/complicações , Neoplasia Endócrina Múltipla Tipo 1/diagnóstico , Neoplasia Endócrina Múltipla Tipo 1/genética
5.
J Environ Manage ; 344: 118513, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37418917

RESUMO

The assessment of waste ecotoxicity (hazardous property HP14 in the European Union) is fundamental for proper waste classification and safe application/disposal. Biotests are relevant for evaluating waste complex matrices, but their efficiency is crucial to encourage their adoption at the industrial level. This work aims at evaluating possibilities of improving the efficiency of a biotest battery previously suggested in the literature, regarding test selection, duration, and/or laboratory resources optimization. Fresh incineration bottom ash (IBA) was the case study. The test battery analysed included standard aquatic (bacteria, microalgae, macrophytes, daphnids, rotifers, fairy shrimp) and terrestrial (bacteria, plants, earthworms, collembolans) organisms. The assessment followed an Extended Limit Test design (three dilutions of eluate or solid IBA) and the Lowest Ineffective Dilution (LID-approach) for ecotoxicity classification. The results emphasize the importance of testing different species. It was also evidenced that tests with daphnids and earthworms may be shortened to 24 h; the miniaturization of tests is suitable as e.g. differential sensitivity of microalgae and macrophytes was captured with low variability; alternative testing kits can be used when methodological difficulties are found. Microalgae were more sensitive than macrophytes. Similar results were found for the Thamnotoxkit and daphnids test for eluates with natural pH, so the former may be used as an alternative. B. rapa was the most sensitive organism, suggesting that it may be tested as the only terrestrial plant species and that minimum test duration is appropriate. F. candida does not appear to add information to the battery. The differences in sensitivity of A. fischeri and E. fetida compared to the remaining species were not significant enough to exclude them from the battery. Thus, this work suggests a biotest battery to test IBA comprising aquatic tests - Aliivibrio fischeri, Raphidocelis subcapitata (miniaturised test), and Daphnia magna (24 h when clear deleterious effects are observed) or Thamnocephalus platyurus (toxkit) - and terrestrial tests - Arthrobacter globiformis, Brassica rapa (14 d), and Eisenia fetida (24 h). Testing waste with natural pH is also recommended. The Extended Limit Test design considering the LID-approach seems useful in waste testing, particularly for the industry, involving low effort, test material requirements, and few laboratory resources. The LID-approach allowed for differentiating ecotoxic from non-ecotoxic effects and captured different sensitivities between species. Ecotoxicological assessment of other waste may benefit from these recommendations, but caution should be taken given the properties of each waste type.


Assuntos
Cinza de Carvão , Incineração , União Europeia , Plantas
6.
Phys Rev Lett ; 129(1): 012501, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35841541

RESUMO

A narrow near-threshold proton-emitting resonance (E_{x}=11.4 MeV, J^{π}=1/2^{+}, and Γ_{p}=4.4 keV) was directly observed in ^{11}B via proton resonance scattering. This resonance was previously inferred in the ß-delayed proton emission of the neutron halo nucleus ^{11}Be. The good agreement between both experimental results serves as a ground to confirm the existence of such exotic decay and the particular behavior of weakly bound nuclei coupled to the continuum. R-matrix analysis shows a sizable partial decay width for both, proton and α (Γ_{α}=11 keV) emission channels.

7.
Appl Opt ; 61(14): 4079-4086, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36256083

RESUMO

We revisit the Fabry-Perot (FP) reflectivity method to measure optical indices in the mid-infrared spectrum. This simple approach can be readily implemented using a standard Fourier transform infrared spectrometer. Measuring samples with multiple heights allows for enhanced precision of the measurement, making the FP method consistent in values and uncertainties with more advanced ellipsometric measurements. An extensive discussion about experimental errors is carried out. Results between 4 and 12 µm for AlInAs, n-doped InGaAs, and InP, which are the most standard materials for quantum cascade lasers, are given.

8.
Clin Exp Dermatol ; 47(1): 72-79, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34235774

RESUMO

BACKGROUND: Better understanding of the experience of people living with hidradenitis suppurativa (HS) is essential to identify gaps in current patient care and inform healthcare decision-making. AIM: To describe the patient experience of individuals with HS, including their path to diagnosis, symptom control, treatments, healthcare utilization, patient needs and impact on quality of life. METHODS: The Hidradenitis Suppurativa Patient Experience survey was created, extensively reviewed and disseminated through engaging HS-related patient organizations, physician groups and social media groups. RESULTS: In total, 537 respondents completed the survey; the mean age was 38 years (range 14-73 years) and 95% (510 of 537) were female. The mean number of treatment types per respondent was 15, and included antibacterial soaps (93.3%; 431 of 462), avoidance of tight clothing (90.9%; 419 of 462), use of oral antibiotics (79.7%; 368 of 462), nonprescription drugs (79.7%; 368 of 462) and topical antibiotics (77.1%; 356 of 262). Pain was poorly controlled in 46% of respondents (184 of 401). HS had a negative impact on the ability to work and attend school for 81% of respondents (337 of 415), with 59% (245 of 415) missing at least 2 days of work a month and 16% (66 of 415) missing > 11 days of work. The mean number of misdiagnoses per respondent was three and the median time to diagnosis was 10 years. CONCLUSION: Individuals with HS experience a delay in diagnosis and have suboptimal control of the disease. We propose 11 recommendations to improve diagnosis, treatment and quality of life for individuals living with HS.


Assuntos
Hidradenite Supurativa , Autorrelato , Adolescente , Adulto , Idoso , Feminino , Hidradenite Supurativa/diagnóstico , Hidradenite Supurativa/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Avaliação de Resultados da Assistência ao Paciente , Qualidade de Vida , Adulto Jovem
9.
Neuroimage ; 236: 118070, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33887473

RESUMO

Cognitive trajectories vary greatly across older individuals, and the neural mechanisms underlying these differences remain poorly understood. Here, we investigate the cognitive variability in older adults by linking the influence of white matter microstructure on the task-related organization of fast and effective communications between brain regions. Using diffusion tensor imaging and electroencephalography, we show that individual differences in white matter network organization are associated with network clustering and efficiency in the alpha and high-gamma bands, and that functional network dynamics partly explain individual differences in cognitive control performance in older adults. We show that older individuals with high versus low structural network clustering differ in task-related network dynamics and cognitive performance. These findings were corroborated by investigating magnetoencephalography networks in an independent dataset. This multimodal (fMRI and biological markers) brain connectivity framework of individual differences provides a holistic account of how differences in white matter microstructure underlie age-related variability in dynamic network organization and cognitive performance.


Assuntos
Envelhecimento/fisiologia , Conectoma , Imagem de Tensor de Difusão , Eletroencefalografia , Função Executiva/fisiologia , Magnetoencefalografia , Memória de Curto Prazo/fisiologia , Rede Nervosa , Desempenho Psicomotor/fisiologia , Substância Branca , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Conectoma/métodos , Imagem de Tensor de Difusão/métodos , Eletroencefalografia/métodos , Feminino , Humanos , Magnetoencefalografia/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/anatomia & histologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Substância Branca/anatomia & histologia , Substância Branca/diagnóstico por imagem , Substância Branca/fisiologia , Adulto Jovem
10.
Phys Rev Lett ; 126(15): 152701, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929230

RESUMO

The discrepancy between observations from γ-ray astronomy of the ^{60}Fe/^{26}Al γ-ray flux ratio and recent calculations is an unresolved puzzle in nuclear astrophysics. The stellar ß-decay rate of ^{59}Fe is one of the major nuclear uncertainties impeding us from a precise prediction. The important Gamow-Teller strengths from the low-lying states in ^{59}Fe to the ^{59}Co ground state are measured for the first time using the exclusive measurement of the ^{59}Co(t,^{3}He+γ)^{59}Fe charge-exchange reaction. The new stellar decay rate of ^{59}Fe is a factor of 3.5±1.1 larger than the currently adopted rate at T=1.2 GK. Stellar evolution calculations show that the ^{60}Fe production yield of an 18 solar mass star is decreased significantly by 40% when using the new rate. Our result eliminates one of the major nuclear uncertainties in the predicted yield of ^{60}Fe and alleviates the existing discrepancy of the ^{60}Fe/^{26}Al ratio.

11.
Phys Chem Chem Phys ; 23(11): 6964-6973, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33730138

RESUMO

Some lithium oxyhalides have been proposed as low-cost solid electrolytes for having room-temperature Li+ conductivity close to commercial liquid electrolytes, but with the advantages of enabling higher energy densities through the use of the Li metal anode and not being flammable. However, the stability of anhydrous anti-perovskite lithium oxyhalides, such as Li3OCl, is not well understood yet: whereas theoretical calculations show they should decompose into lithium halides and Li2O (except at high temperatures), there is no experimental evidence of such decomposition. Thus, here we use a combination of analytical calculations and force-field-based atomistic modelling to investigate the role of kinetics in the stability of anhydrous Li3OCl. The results show that due to sluggish Cl- and O2- transport this material has good kinetic stability below ∼400 K under high concentration gradients, below ∼450 K under typical cell voltages, and at all temperatures against local composition fluctuations. Furthermore, the good kinetic stability explains the apparent discrepancy between theoretical thermodynamics calculations and experimental observations and contributes to enlighten the nature and extent of this material's stability. The methods presented here can also be extended to other battery materials that are predicted to decompose, to access the safe temperature range they can undergo without degrading.

12.
J Endocrinol Invest ; 44(11): 2367-2374, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33683662

RESUMO

PURPOSE: Brain tumors are the most common solid tumor in children. The prevalence of survivors from these cancers has been increasing, presenting endocrine sequelae in more than 40% of the cases. Our aim was to characterize the endocrinopathies diagnosed in this population, exploring the outcomes of growth hormone treatment. METHODS: We have performed a retrospective analysis of the survivors that were followed-up through a close protocol at our endocrine late-effects clinic. RESULTS: 242 survivors, followed during 6.4 (0-23.4) years, were considered. The median age at tumor diagnosis was 6.7 (0-18) years and pilocytic astrocytoma was the most frequent neoplasm (33.5%). The prevalence of endocrinopathies was of 71.5%, with growth hormone deficiency being the most frequent (52.9%). An indirect correlation between the age at the beginning of somatropin and growth velocity in the first year of treatment was observed. Those treated with craniospinal radiotherapy presented a smaller final upper/lower segments ratio comparing with those that only received cranial radiotherapy. However, their final height was not compromised when compared to their family height target. We found pubertal delay in 12%; accelerated/precocious puberty in 13.2%; central and primary hypogonadism in 21.9% and 3.3%, respectively; primary and central hypothyroidism in 23.6% and 14.5%, respectively; thyroid nodules in 7.4%; ACTH deficiency in 10.3% and diabetes insipidus in 12%. CONCLUSION: This study reveals a higher prevalence of endocrinopathies in brain tumors survivors and explores the influence of craniospinal irradiation in the adult body proportions. It reinforces the importance of routine follow-up among survivors.


Assuntos
Neoplasias Encefálicas , Sobreviventes de Câncer/estatística & dados numéricos , Doenças do Sistema Endócrino , Transtornos do Crescimento , Hormônio do Crescimento , Radioterapia , Adolescente , Fatores Etários , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Criança , Diabetes Insípido/diagnóstico , Diabetes Insípido/etiologia , Doenças do Sistema Endócrino/diagnóstico , Doenças do Sistema Endócrino/epidemiologia , Doenças do Sistema Endócrino/etiologia , Feminino , Seguimentos , Transtornos do Crescimento/epidemiologia , Transtornos do Crescimento/etiologia , Transtornos do Crescimento/metabolismo , Transtornos do Crescimento/terapia , Hormônio do Crescimento/análise , Hormônio do Crescimento/deficiência , Hormônio do Crescimento/uso terapêutico , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Hipotireoidismo/diagnóstico , Hipotireoidismo/epidemiologia , Hipotireoidismo/etiologia , Masculino , Portugal/epidemiologia , Prevalência , Puberdade Tardia/diagnóstico , Puberdade Tardia/epidemiologia , Puberdade Tardia/etiologia , Radioterapia/efeitos adversos , Radioterapia/métodos , Radioterapia/estatística & dados numéricos
13.
Water Sci Technol ; 83(8): 1781-1796, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33905352

RESUMO

Organochlorines have diverse structures and applications and are included in the list of persistent organic pollutants (POPs) due to their toxicity and environmental persistence. The reduced capacity of conventional wastewater treatment plants to remove these compounds encourages the development of cost-effective and efficient remediation approaches. Fungal biotechnology can contribute to the development of these technologies through their enzymatic machinery but faces several drawbacks related to the use of dispersed mycelium. In this sense, investigations concerning the degradation of organochlorines using immobilized fungi demonstrated an increase in contaminant removal efficiency compared with degradation by free cells. Despite this interest, the mechanisms of immobilized fungi have not been comprehensively reviewed. In this paper, recent advances of laboratory and field studies in organochlorine compounds removal by fungi are reviewed, focusing on the role of immobilization techniques. Firstly, the mechanisms of organochlorines bioconversion by fungi and the factors affecting enzyme activity are elucidated and discussed in detail. Then, the main targeted compounds, fungi, technics, and materials used for immobilization are discussed, as well as their advantages and limitations. Furthermore, critical points for future studies of fungi immobilization for organochlorine removal are proposed.


Assuntos
Hidrocarbonetos Clorados , Purificação da Água , Fungos , Micélio
14.
Bull Environ Contam Toxicol ; 107(1): 131-139, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33847799

RESUMO

The large-scale use of pesticides is one of the main causes of the dramatic degradation of our environment. Pesticides such as imidacloprid (IMID) have been linked to declines in bee health and toxicity to other beneficial insects. They pose a threat to human health due to their persistence in the environment and accumulation in the food chain. Therefore, it is essential to test possible environmentally-friendly solutions for their elimination. The present study evaluates the efficiency of microalgae Nannochloropsis sp. for the removal of IMID from synthetic wastewater. The influence of aeration, light, and the presence of UV radiation on the degradation of IMID were factors considered in the study. A rapid RP-HPLC method was developed and validated for the analysis and quantification of IMID in the context of bioremediation with microalgae. Nannochloropsis sp. removed 4.39 µg mL-1 from an initial content of 9.59 µg mL-1 (reaching approximately 50%) of IMID in the first 20 h. This study demonstrated that the removal of IMID by the marine microalgae Nannochloropsis sp. is both effective and light-dependent.


Assuntos
Microalgas , Estramenópilas , Animais , Abelhas , Cromatografia Líquida de Alta Pressão , Neonicotinoides , Nitrocompostos , Águas Residuárias , Água
15.
Phys Rev Lett ; 125(23): 232501, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33337204

RESUMO

The neutron-rich nuclei in the N=28 island of inversion have attracted considerable experimental and theoretical attention, providing great insight into the evolution of shell structure and nuclear shape in exotic nuclei. In this work, for the first time, quadrupole collectivity is assessed simultaneously on top of the 3/2^{-} ground state and the 7/2^{-} shape-coexisting isomer of ^{43}S, putting the unique interpretation of shape and configuration coexistence at N=27 and 28 in the sulfur isotopic chain to the test. From an analysis of the electromagnetic transition strengths and quadrupole moments predicted within the shell model, it is shown that the onset of shape coexistence and the emergence of a simple collective structure appear suddenly in ^{43}S with no indication of such patterns in the N=27 isotone ^{45}Ar.

16.
Phys Rev Lett ; 125(26): 262701, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33449748

RESUMO

The interpretation of observations of cooling neutron star crusts in quasipersistent x-ray transients is affected by predictions of the strength of neutrino cooling via crust Urca processes. The strength of crust Urca neutrino cooling depends sensitively on the electron-capture and ß-decay ground-state-to-ground-state transition strengths of neutron-rich rare isotopes. Nuclei with a mass number of A=61 are predicted to be among the most abundant in accreted crusts, and the last remaining experimentally undetermined ground-state-to-ground-state transition strength was the ß decay of ^{61}V. This Letter reports the first experimental determination of this transition strength, a ground-state branching of 8.1_{-3.1}^{+4.0}%, corresponding to a log ft value of 5.5_{-0.2}^{+0.2}. This result was achieved through the measurement of the ß-delayed γ rays using the total absorption spectrometer SuN and the measurement of the ß-delayed neutron branch using the neutron long counter system NERO at the National Superconducting Cyclotron Laboratory at Michigan State University. This method helps to mitigate the impact of the pandemonium effect in extremely neutron-rich nuclei on experimental results. The result implies that A=61 nuclei do not provide the strongest cooling in accreted neutron star crusts as expected by some predictions, but that their cooling is still larger compared to most other mass numbers. Only nuclei with mass numbers 31, 33, and 55 are predicted to be cooling more strongly. However, the theoretical predictions for the transition strengths of these nuclei are not consistently accurate enough to draw conclusions on crust cooling. With the experimental approach developed in this work, all relevant transitions are within reach to be studied in the future.

17.
Phys Rev Lett ; 125(20): 202701, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33258618

RESUMO

Type-I x-ray bursts can reveal the properties of an accreting neutron star system when compared with astrophysics model calculations. However, model results are sensitive to a handful of uncertain nuclear reaction rates, such as ^{22}Mg(α,p). We report the first direct measurement of ^{22}Mg(α,p), performed with the Active Target Time Projection Chamber. The corresponding astrophysical reaction rate is orders of magnitude larger than determined from a previous indirect measurement in a broad temperature range. Our new measurement suggests a less-compact neutron star in the source GS1826-24.

18.
Rev Chil Pediatr ; 91(3): 385-390, 2020 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-32730519

RESUMO

INTRODUCTION: Heavy Menstrual Bleeding (EMB) is a frequent problem in adolescence. The prevalence of inherited bleeding disorders (IBD) as a cause of EMB is not well established and the involvement of fibri nolytic pathway defects has been poorly explored. OBJECTIVE: To determine the prevalence of IBD and fibrinolysis defects in adolescents with EMBs. PATIENTS AND METHOD: 93 adolescents (11 to 18 years old) were included. Personal and family history of bleeding were obtained through a standard ized questionnaire. The following lab tests were performed: prothrombin time (PT), activated partial thromboplastin time (aPTT), von Willebrand factor quantification, and platelet count and function. Those patients who were not diagnosed with IBD were further evaluated with clot lysis time assay. RESULTS: 41 patients (44%) were diagnosed as IBD (Von Willebrand disease n = 28, platelet func tion defects n=8, mild hemophilia n = 5. Decreased clot lysis time was found in 31 patients. 54% of patients diagnosed with IBD had EMB as the first hemorrhagic manifestation. CONCLUSION: These results support the need to evaluate the coagulation process, including the fibrinolytic pathway in the study of adolescents with EMB.


Assuntos
Transtornos Herdados da Coagulação Sanguínea/complicações , Transtornos Herdados da Coagulação Sanguínea/diagnóstico , Fibrinólise , Menorragia/etiologia , Adolescente , Transtornos da Coagulação Sanguínea/complicações , Transtornos da Coagulação Sanguínea/diagnóstico , Transtornos Herdados da Coagulação Sanguínea/epidemiologia , Transtornos Herdados da Coagulação Sanguínea/fisiopatologia , Testes de Coagulação Sanguínea , Criança , Estudos Transversais , Feminino , Humanos , Prevalência
19.
Phys Rev Lett ; 122(23): 232701, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31298878

RESUMO

The ^{23}Al(p,γ)^{24}Si reaction is among the most important reactions driving the energy generation in type-I x-ray bursts. However, the present reaction-rate uncertainty limits constraints on neutron star properties that can be achieved with burst model-observation comparisons. Here, we present a novel technique for constraining this important reaction by combining the GRETINA array with the neutron detector LENDA coupled to the S800 spectrograph at the National Superconducting Cyclotron Laboratory. The ^{23}Al(d,n) reaction was used to populate the astrophysically important states in ^{24}Si. This enables a measurement in complete kinematics for extracting all relevant inputs necessary to calculate the reaction rate. For the first time, a predicted close-lying doublet of a 2_{2}^{+} and (4_{1}^{+},0_{2}^{+}) state in ^{24}Si was disentangled, finally resolving conflicting results from two previous measurements. Moreover, it was possible to extract spectroscopic factors using GRETINA and LENDA simultaneously. This new technique may be used to constrain other important reaction rates for various astrophysical scenarios.

20.
Crit Rev Toxicol ; 49(5): 411-429, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31268799

RESUMO

Caenorhabditis elegans has been an invaluable model organism in research fields such as developmental biology and neurobiology. Neurotoxicity is one of the subfields greatly profiting from the C. elegans model within biomedical context, while the corresponding potential of the organism applied to environmental studies is relevant but has been largely underexplored. Within the biomedical scope, the implication of metals and organic chemicals with pesticide activity (hereinafter designated as pesticides) in the etiology of several neurodegenerative diseases has been extensively investigated using this nematode as a primary model organism. Additionally, as a well-known experimental model bearing high sensitivity to different contaminants and representing important functional levels in soil and aquatic ecosystems, C. elegans has high potential to be extensively integrated within Environmental Risk Assessment (ERA) routines. In spite of the recognition of some regulatory agencies, this actual step has yet to be made. The purpose of this review is to discuss the major advantages supporting the inclusion of C. elegans in lower tiers of ERA. Special emphasis was given to its sensitivity to metals and pesticides, which is similar to that of other model organisms commonly used in ERA (e.g. Daphnia magna and Eisenia sp.), and to the large array of endpoints that can be tested with the species, both concerning the aquatic and the soil compartments. The inclusion of C. elegans testing may hence represent a relevant advance in ERA, providing ecologically relevant insights toward improvement of the regulatory capacity for establishing appropriate environmental protection benchmarks.


Assuntos
Caenorhabditis elegans/fisiologia , Monitoramento Ambiental/métodos , Animais , Metais/toxicidade , Modelos Teóricos , Praguicidas/toxicidade , Medição de Risco
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