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1.
Phys Rev Lett ; 132(21): 211804, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38856254

RESUMEN

We measure the tau-to-light-lepton ratio of inclusive B-meson branching fractions R(X_{τ/ℓ})≡B(B→Xτν)/B(B→Xℓν), where ℓ indicates an electron or muon, and thereby test the universality of charged-current weak interactions. We select events that have one fully reconstructed B meson and a charged lepton candidate from 189 fb^{-1} of electron-positron collision data collected with the Belle II detector. We find R(X_{τ/ℓ})=0.228±0.016(stat)±0.036(syst), in agreement with standard-model expectations. This is the first direct measurement of R(X_{τ/ℓ}).

2.
Phys Rev Lett ; 130(7): 071802, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36867815

RESUMEN

An absolute measurement of the Λ_{c}^{+} lifetime is reported using Λ_{c}^{+}→pK^{-}π^{+} decays in events reconstructed from data collected by the Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider. The total integrated luminosity of the data sample, which was collected at center-of-mass energies at or near the ϒ(4S) resonance, is 207.2 fb^{-1}. The result, τ(Λ_{c}^{+})=203.20±0.89±0.77 fs, where the first uncertainty is statistical and the second systematic, is the most precise measurement to date and is consistent with previous determinations.

3.
Phys Rev Lett ; 130(7): 071804, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36867830

RESUMEN

The dark photon A^{'} and the dark Higgs boson h^{'} are hypothetical particles predicted in many dark sector models. We search for the simultaneous production of A^{'} and h^{'} in the dark Higgsstrahlung process e^{+}e^{-}→A^{'}h^{'} with A^{'}→µ^{+}µ^{-} and h^{'} invisible in electron-positron collisions at a center-of-mass energy of 10.58 GeV in data collected by the Belle II experiment in 2019. With an integrated luminosity of 8.34 fb^{-1}, we observe no evidence for signal. We obtain exclusion limits at 90% Bayesian credibility in the range of 1.7-5.0 fb on the cross section and in the range of 1.7×10^{-8}-200×10^{-8} on the effective coupling ϵ^{2}×α_{D} for the A^{'} mass in the range of 4.0 GeV/c^{2}

4.
Phys Rev Lett ; 131(5): 051804, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37595249

RESUMEN

We present the first measurement of the ratio of branching fractions of inclusive semileptonic B-meson decays, R(X_{e/µ})=B(B→Xeν)/B(B→Xµν), a precision test of electron-muon universality, using data corresponding to 189 fb^{-1} from electron-positron collisions collected with the Belle II detector. In events where the partner B meson is fully reconstructed, we use fits to the lepton momentum spectra above 1.3 GeV/c to obtain R(X_{e/µ})=1.007±0.009(stat)±0.019(syst), which is the most precise lepton-universality test of its kind and agrees with the standard-model expectation.

5.
Phys Rev Lett ; 131(12): 121802, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37802942

RESUMEN

We report the first search for a nonstandard-model resonance decaying into τ pairs in e^{+}e^{-}→µ^{+}µ^{-}τ^{+}τ^{-} events in the 3.6-10 GeV/c^{2} mass range. We use a 62.8 fb^{-1} sample of e^{+}e^{-} collisions collected at a center-of-mass energy of 10.58 GeV by the Belle II experiment at the SuperKEKB collider. The analysis probes three different models predicting a spin-1 particle coupling only to the heavier lepton families, a Higgs-like spin-0 particle that couples preferentially to charged leptons (leptophilic scalar), and an axionlike particle, respectively. We observe no evidence for a signal and set exclusion limits at 90% confidence level on the product of cross section and branching fraction into τ pairs, ranging from 0.7 to 24 fb, and on the couplings of these processes. We obtain world-leading constraints on the couplings for the leptophilic scalar model for masses above 6.5 GeV/c^{2} and for the axionlike particle model over the entire mass range.

6.
Anaesthesia ; 77(6): 684-690, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35238406

RESUMEN

The use of deliberate deception in simulation allows for a level of realism that is not normally feasible. However, the use of deception is controversial, and carries the risk of psychological harm to learners. There are currently no quantitative data on the effect of deception on learner performance, making it difficult to judge its usefulness. The objective of this study was to examine the impact of deception on learners' performance during a life-threatening scenario. In this simulation study, second-year anaesthesia residents were randomly allocated into two groups: the non-deception group was told that the participating consultant was acting a part, while the deception group was told that the consultant was a subject in the study. Learners then participated in a simulated crisis that presented them with situational opportunities to challenge the consultant regarding clearly wrong decisions. Two independent raters scored the performances using the modified advocacy-inquiry scale. Forty-four participants were analysed. The median (IQR [range]) highest scoring modified advocacy-inquiry scale was 5.0 (4.5-5.1 [4.0-5.5]) for the non-deception group and 4.0 (3.0-4.0 [2.5-5.0]) for the deception group, (p < 0.001), and the median total number of challenges per participant was 26.8 (21.0-31.1 [16.5-35.5]) and 18.0 (14.3-23.3 [7.0-33.0]), respectively (p = 0.001). Trainees exposed to deliberate deception, who thought that the consultant anaesthetist was a subject, had a less-effective best challenge, likely mimicking real-life behaviour. Deliberate deception appears to modify behaviour, particularly relating to communication involving hierarchical relationships. This technique may improve authenticity, especially with a steep power gradient, and so has demonstrable value which must be balanced against the ethical considerations.


Asunto(s)
Anestesia , Anestesiología , Internado y Residencia , Anestesiología/educación , Competencia Clínica , Comunicación , Decepción , Humanos
7.
J Environ Manage ; 307: 114505, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35085973

RESUMEN

Due to increased contribution from agriculture sector to total greenhouse gas emissions, there is need to study the ability of no-tilled diverse cropping systems including crop sequences and bio-covers to mitigate C equivalent emissions. Thus, C-footprint was calculated for a long-term experiment at the University of Tennessee's Research and Education Center in Milan with six-crop sequences: continuous cotton (Gossypium hirsutum L.), cotton-corn (Zea mays L.), continuous corn, corn-soybean (Glycine max L.), continuous soybean, and soybean-cotton interacted with four bio-covers: poultry litter, hairy vetch (Vicia villosa), winter wheat (Triticum aestivum), and fallow control with three replicates in a strip-plot design. During the experiment duration (2002-2017), field inputs (fertilizers, pesticides, and machinery used for planting, chemical applications, and harvesting) and outputs (crop yield, aboveground, and belowground residue) were assessed for each crop sequence/bio-cover combination to calculate total C equivalence of inputs and outputs, net C gain, C footprint per kg yield, sustainability index, and nitrous oxide emissions. For continuous corn, C-based input emissions were significantly higher by 0.28-0.62 Mg CO2 eq. ha-1 yr-1 than all other sequences, however, a greater net C gain (5.4 Mg C eq. ha-1 yr-1) was also observed due to increased crop yield, aboveground and belowground residues. Poultry litter application resulted in lower C-footprint (1.59-2.09 kg CO2 eq. kg-1 yield) than hairy vetch, wheat, and fallow under all crop sequences. Hairy vetch also lowered C-footprint per kg yield (∼2-14%) when compared with wheat under continuous systems of corn, soybean, and cotton, and cotton-corn rotation. Poultry litter application increased sustainability index (23-45) of all cropping sequences compared with other bio-covers. Hairy vetch improved sustainability index of corn including cropping sequences as compared with wheat and fallow. Inclusion of soybean and cotton with corn significantly decreased nitrous oxide emissions by 20-25%. The major factor contributing towards C-based input emissions was N fertilizer with 68% contribution to total emissions on average. It is concluded that application of poultry litter can reduce per yield C-footprint and enhance production system sustainability compared with hairy vetch, wheat, and fallow for monocultures or rotations of corn, soybean, cotton. Additionally, hairy vetch can outperform wheat in reducing the per yield C-footprint for continuous corn/soybean/cotton, and cotton-corn rotation. Especially for corn production systems, hairy vetch can enhance sustainability index compared with wheat and fallow. In order to increase per hectare net C gain, reduce per yield C-footprint and enhance sustainability index simultaneously, integration of continuous corn or corn-soybean/cotton rotation with bio-cover poultry litter or hairy vetch may perform better than the monocultures of soybean or cotton integrated with bio-cover wheat or fallow control in the Mid-south USA.


Asunto(s)
Huella de Carbono , Carbono , Agricultura , Fertilizantes , Nitrógeno/análisis , Suelo , Zea mays
8.
Med Oral Patol Oral Cir Bucal ; 27(1): e85-e93, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34874924

RESUMEN

BACKGROUND: This study reviews the demographic, clinical and radiographic features of adenomatoid odontogenic tumor(AOT) diagnosed in an Indian population over 50 years and also evaluate and compare follicular AOT(F-AOT) and extra-follicular AOT(EF-AOT). MATERIAL AND METHODS: 55 diagnosed cases of AOT from 1971-2020 were studied retrospectively. The data regarding the age, sex, location, variant of AOT, duration, clinical features, radiographic appearance, treatment and recurrence were collected and analysed. RESULTS: Of the 722 odontogenic tumors diagnosed, 7.6% were AOTs with higher prevalence of extra-follicular (67.3%) than follicular (32.7%) variant. All the tumors were intraosseous with a marked predilection for maxilla over mandible, ratio 2:1. The patients mean age was 19.8 years with slightly higher female predilection (male:female ratio - 1:1.5). The anterior region (76.4%) was more frequently affected and entire quadrant was involved in 21.8% cases. Clinically, asymptomatic, slow-growing swelling was seen in 81.8% cases with duration of 15 days to 10 years. Radiographically, AOT appeared as well-corticated radiolucent lesion. Canine was the most commonly impacted tooth. Recurrence was seen in 3 cases. CONCLUSIONS: Interestingly, in this series extra-follicular was twice more common than follicular AOT. Few cases involved the entire quadrant or crossed the midline of either jaws.


Asunto(s)
Ameloblastoma , Tumores Odontogénicos , Diente Impactado , Adolescente , Adulto , Niño , Femenino , Humanos , India , Masculino , Tumores Odontogénicos/diagnóstico por imagen , Tumores Odontogénicos/epidemiología , Estudios Retrospectivos , Adulto Joven
9.
Phys Rev Lett ; 127(18): 181802, 2021 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-34767404

RESUMEN

A search for the flavor-changing neutral-current decay B^{+}→K^{+}νν[over ¯] is performed at the Belle II experiment at the SuperKEKB asymmetric energy electron-positron collider. The data sample corresponds to an integrated luminosity of 63 fb^{-1} collected at the ϒ(4S) resonance and a sample of 9 fb^{-1} collected at an energy 60 MeV below the resonance. Because the measurable decay signature involves only a single charged kaon, a novel measurement approach is used that exploits not only the properties of the B^{+}→K^{+}νν[over ¯] decay, but also the inclusive properties of the other B meson in the ϒ(4S)→BB[over ¯] event, to suppress the background from other B meson decays and light-quark pair production. This inclusive tagging approach offers a higher signal efficiency compared to previous searches. No significant signal is observed. An upper limit on the branching fraction of B^{+}→K^{+}νν[over ¯] of 4.1×10^{-5} is set at the 90% confidence level.

10.
Phys Rev Lett ; 127(21): 211801, 2021 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-34860075

RESUMEN

We report a measurement of the D^{0} and D^{+} lifetimes using D^{0}→K^{-}π^{+} and D^{+}→K^{-}π^{+}π^{+} decays reconstructed in e^{+}e^{-}→cc[over ¯] data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The data, collected at center-of-mass energies at or near the ϒ(4S) resonance, correspond to an integrated luminosity of 72 fb^{-1}. The results, τ(D^{0})=410.5±1.1(stat)±0.8(syst) fs and τ(D^{+})=1030.4±4.7(stat)±3.1(syst) fs, are the most precise to date and are consistent with previous determinations.

11.
J Appl Microbiol ; 131(6): 3069-3080, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34048109

RESUMEN

AIM: The present study demonstrated the antimicrobial activity of ferulic acid and p-coumaric acid against unstressed and stressed (cold stressed, starved and desiccated) Cronobacter sakazakii in laboratory media (37°C) and reconstituted powdered infant formulation (PIF) with mild heat treatment (50°C). METHODS AND RESULTS: Five phenolics, namely, quercetin, rutin, caffeic acid, ferulic acid and p-coumaric acid, were tested for antimicrobial activities against five strains of C. sakazakii either unstressed or stressed. Strain specific higher resistance to ferulic acid and p-coumaric acid was observed after stress adaptation in laboratory media. The effect of cross protection was validated using reconstituted PIF as delivery vehicle of selected compounds. Both p-coumaric acid and ferulic acid showed inhibition of C. sakazakii in a dose and time dependent manner as revealed by their viable cell counts. Principal component analysis revealed that the desiccated cells were more sensitive to phenolics in reconstituted PIF. CONCLUSIONS: Only ferulic acid and p-coumaric acid showed marked antibacterial activity with minimum inhibitory concentration in the range of 2·5-5 mg ml-1 for unstressed C. sakazakii cells in tryptone soy broth. The maximum inhibition was achieved with 20 mg ml-1 of both the tested polyphenols in reconstituted PIF. Cold stress and starvation stress did not impart any protection nor increased the susceptibility of C. sakazakii, whereas desiccation resulted in increased susceptibility to phenolic compounds. SIGNIFICANCE AND IMPACT OF THE STUDY: The results obtained in this study helps in understanding the effect of environmental stresses during processing on susceptibility of C. sakazakii to natural antimicrobial agents. Future transcriptomic studies and functional genetic studies are warranted to understand the strain specific stress responses for the development of better control methods possibly by using these natural antagonists.


Asunto(s)
Cronobacter sakazakii , Ácidos Cumáricos , Microbiología de Alimentos , Humanos , Lactante , Fórmulas Infantiles , Análisis Multivariante , Estrés Fisiológico
12.
Climacteric ; 24(4): 415-420, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33719783

RESUMEN

OBJECTIVE: The present study aimed to determine the effect of estrogen receptor (ER) agonists on depression and memory impairment in insulin-resistant ovariectomized (OVX) rats. METHODS: Rats underwent bilateral ovariectomy, and low-dose streptozotocin (STZ) and a high-fat diet (58% fat, 25% protein, and 17% carbohydrates as a percentage of kilocalories) were administered to induce an estrogen-deficient insulin-resistant state. After 1 week of STZ administration, rats were treated with 17ß-estradiol (17ßE2) and selective ER-α (propylpyrazoletriol) and ER-ß (diarylpropionitrile) agonists (10 µg/kg subcutaneously). Memory was evaluated using the Morris water maze and depression using the forced swim test. RESULTS: Treatment with selective ER-ß agonist and 17ßE2 but not with selective ER-α agonist significantly modulated the neurobehavioral deficits in insulin-resistant OVX rats. These neurobehavioral parameters were further correlated with brain-derived neurotrophic factor (BDNF) levels and acetylcholinesterase (AChE) activity. Selective ER-ß agonist and 17ßE2 significantly modulated BDNF levels and AChE activity in insulin-resistant OVX rats. Significant increases in estradiol and uterine weight were observed in 17ßE2-treated rats, but selective ER agonists did not show any effect. CONCLUSION: ER-ß agonist can be an effective strategy for the mitigation of memory loss and depression in an estrogen-deficient insulin-resistant state without all of the deleterious feminizing effects that occur with the use of 17ßE2.


Asunto(s)
Estrógenos , Insulina , Acetilcolinesterasa , Animales , Factor Neurotrófico Derivado del Encéfalo , Estradiol/farmacología , Ratas
13.
J Med Biol Eng ; 41(5): 678-689, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34483791

RESUMEN

Purpose: In early 2020, the world is amid a significant pandemic due to the novel coronavirus disease outbreak, commonly called the COVID-19. Coronavirus is a lung infection disease caused by the Severe Acute Respiratory Syndrome Coronavirus 2 virus (SARS-CoV-2). Because of its high transmission rate, it is crucial to detect cases as soon as possible to effectively control the spread of this pandemic and treat patients in the early stages. RT-PCR-based kits are the current standard kits used for COVID-19 diagnosis, but these tests take much time despite their high precision. A faster automated diagnostic tool is required for the effective screening of COVID-19. Methods: In this study, a new semi-supervised feature learning technique is proposed to screen COVID-19 patients using chest CT scans. The model proposed in this study uses a three-step architecture, consisting of a convolutional autoencoder based unsupervised feature extractor, a multi-objective genetic algorithm (MOGA) based feature selector, and a Bagging Ensemble of support vector machines based binary classifier. The proposed architecture has been designed to provide precise and robust diagnostics for binary classification (COVID vs.nonCOVID). A dataset of 1252 COVID-19 CT scan images, collected from 60 patients, has been used to train and evaluate the model. Results: The best performing classifier within 127 ms per image achieved an accuracy of 98.79%, the precision of 98.47%, area under curve of 0.998, and an F1 score of 98.85% on 497 test images. The proposed model outperforms the current state of the art COVID-19 diagnostic techniques in terms of speed and accuracy. Conclusion: The experimental results prove the superiority of the proposed methodology in comparison to existing methods.The study also comprehensively compares various feature selection techniques and highlights the importance of feature selection in medical image data problems.

14.
Phys Rev Lett ; 125(16): 161806, 2020 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-33124872

RESUMEN

We present a search for the direct production of a light pseudoscalar a decaying into two photons with the Belle II detector at the SuperKEKB collider. We search for the process e^{+}e^{-}→γa, a→γγ in the mass range 0.2

15.
Gynecol Endocrinol ; 36(5): 469-472, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31793366

RESUMEN

Primary hyperparathyroidism presenting first time with severe hypercalcemia is rare in pregnancy. We report a case of primary hyperparathyroidism due to a cystic parathyroid adenoma presenting as severe hypercalcemia with acute pancreatitis in second trimester of pregnancy. Acute pancreatitis was managed by conservative treatment. Hypercalcemia failed to respond to medical management and ultimately responded to ultrasound-guided ethanol ablation of parathyroid adenoma. The delivery was uneventful and patient continues to remain normocalcemic during follow up. As such, ethanol ablation of parathyroid adenoma may be considered during pregnancy in case of failure of response to medical management and when surgical removal of parathyroid adenoma is not safe.


Asunto(s)
Adenoma/diagnóstico por imagen , Hipercalcemia/etiología , Hiperparatiroidismo Primario/complicaciones , Pancreatitis/etiología , Neoplasias de las Paratiroides/diagnóstico por imagen , Complicaciones del Embarazo/etiología , Técnicas de Ablación , Adenoma/complicaciones , Adenoma/cirugía , Adulto , Etanol , Femenino , Humanos , Neoplasias de las Paratiroides/complicaciones , Neoplasias de las Paratiroides/cirugía , Embarazo , Ultrasonografía Intervencional
16.
Andrologia ; 49(7)2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27620003

RESUMEN

The present investigation was carried out to evaluate the possible radioprotective potential of an Aloe vera extract against whole-body X-ray irradiation-induced testicular alterations in mice. Male balb/c mice were divided into four groups: control, A. vera, X-ray and A. vera pre-treated + X-ray irradiated. Histopathological examination revealed significant structural alterations in testes after X-ray exposure, which was also associated with the presence of apoptotic cells as assessed by TUNEL assay. X-ray irradiation resulted in elevation in the levels of reactive oxygen species, lipid peroxidation, a reduction in glutathione concentration and enhanced activities of antioxidant enzymes such as glutathione reductase, glutathione peroxidase, catalase, superoxide dismutase and glutathione-S-transferase. Sperm count/motility and testosterone levels were significantly decreased in the irradiated group. Irradiated animals pre-treated with A. vera extract revealed an improvement in antioxidant status, inhibition of lipid peroxides, apoptotic cell formation and enhanced testicular parameters when compared to the X-ray-exposed group. These findings suggest that A. vera extract could ameliorate X-ray-induced damage due to its free radical scavenging properties and its potential to boost cellular antioxidant defence machinery.


Asunto(s)
Aloe/química , Extractos Vegetales/uso terapéutico , Traumatismos por Radiación/prevención & control , Enfermedades Testiculares/etiología , Enfermedades Testiculares/prevención & control , Rayos X/efectos adversos , Animales , Antioxidantes/análisis , Apoptosis/efectos de la radiación , Depuradores de Radicales Libres , Glutatión/análisis , Etiquetado Corte-Fin in Situ , Peroxidación de Lípido/efectos de la radiación , Masculino , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/administración & dosificación , Protectores contra Radiación , Especies Reactivas de Oxígeno/análisis , Recuento de Espermatozoides , Motilidad Espermática/efectos de la radiación , Enfermedades Testiculares/patología , Testículo/patología , Testículo/efectos de la radiación , Testosterona/sangre , Irradiación Corporal Total
17.
J Intellect Disabil Res ; 61(7): 682-696, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28612475

RESUMEN

OBJECTIVE(S): Although rates of human immunodeficiency virus (HIV) are similar for individuals with and without intellectual and developmental disabilities (IDD), very little is known about the health needs and service use of those with IDD and HIV. Among a population with IDD, we compared the physical and mental health profiles, as well as general and mental health service use for those with and without HIV. DESIGN: Retrospective cohort study in Ontario, Canada using linked administrative health and social service databases. METHODS: The prevalence of physical conditions and mental health disorders, and patterns of service use for any reason and service use for mental health issues were compared among Ontario adults with IDD and HIV (n = 107) and without HIV (n = 63 901) in log-binomial models adjusted for age, sex and neighbourhood income and rurality. RESULTS: Adults with IDD and HIV were more likely than those without HIV to have three types of mental health disorders: non-psychotic disorders [aRR: adjusted rate ratio (aRR): 1.22 (95% confidence interval (CI): 1.01-1.47)], psychotic disorders [aRR: 1.57 (1.09, 2.28)] and substance use disorders [aRR: 3.52 (2.53, 4.91)]. Adults with IDD and HIV were also more likely to have emergency department visits [aRR: 1.68 (1.42, 1.98)] and hospital admissions [aRR: 2.55 (1.74, 3.73)] for any reason, and to have mental health emergency department visits and/or admissions [aRR: 2.82 (1.90, 4.18)]. DISCUSSION: Adults with IDD and HIV have complex health profiles and greater health service use than HIV-negative adults with IDD. These findings call for closer integration of programs delivered by the HIV and disability sectors to optimise the health of this patient population.


Asunto(s)
Discapacidades del Desarrollo/epidemiología , Infecciones por VIH/epidemiología , Discapacidad Intelectual/epidemiología , Trastornos Mentales/epidemiología , Evaluación de Necesidades/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Adolescente , Adulto , Comoras , Discapacidades del Desarrollo/terapia , Femenino , Infecciones por VIH/terapia , Humanos , Discapacidad Intelectual/terapia , Masculino , Trastornos Mentales/terapia , Persona de Mediana Edad , Ontario/epidemiología , Estudios Retrospectivos , Adulto Joven
18.
Br J Surg ; 103(4): 427-33, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26805948

RESUMEN

BACKGROUND: Severity classification systems aim to stratify patients with acute pancreatitis reliably into coherent risk groups. Recently, the Atlanta 1992 classification has been revised (Atlanta 2012) and a novel determinant-based classification (DBC) system developed. This study assessed the ability of the three systems to stratify disease severity among patients with acute pancreatitis. METHODS: This was an observational cohort study of patients with acute pancreatitis identified from an institutional database. Cohort characteristics, investigations, interventions and outcomes were identified. Systems were compared using receiver operating characteristic (ROC) analysis and Spearman's correlation coefficients. RESULTS: The in-hospital mortality rate was 6·6 per cent (15 of 228 patients). All of the outcomes considered correlated significantly with the three systems, with the exception of the need for surgery in Atlanta 1992. Atlanta 2012 and the DBC had higher area under the curve (AUC) values than Atlanta 1992 for all outcomes. The revised Atlanta and DBC systems both performed similarly with regard to ICU admission (AUC 0·927 and 0·917 respectively; both P < 0·001), need for percutaneous drainage (AUC 0·879 and 0·891; both P < 0·001), need for surgery (AUC 0·827 and 0·845; P = 0·006 and P = 0·004 respectively) and in-hospital mortality (0·955 and 0·931; both P < 0·001). However, the critical category in the DBC system identified patients with the most severe disease; seven of eight patients in this group died in hospital, compared with 15 of 34 with severe pancreatitis according to Atlanta 2012. CONCLUSION: The Atlanta 2012 and DBC perform equally well for classification of disease severity in acute pancreatitis. The addition of a critical category in the DBC identifies patients with the most severe disease.


Asunto(s)
Pancreatitis Aguda Necrotizante/clasificación , Adulto , Anciano , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria/tendencias , Humanos , Masculino , Persona de Mediana Edad , Pancreatitis Aguda Necrotizante/diagnóstico , Pancreatitis Aguda Necrotizante/mortalidad , Pronóstico , Curva ROC , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Tasa de Supervivencia/tendencias , Reino Unido/epidemiología
19.
Nanotechnology ; 27(49): 495602, 2016 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-27823993

RESUMEN

In intense pulsed light sintering (IPL), pulsed large-area visible light from a xenon lamp is absorbed by nanoparticle films or patterns and converted to heat, resulting in rapid sintering of the nanoparticles. This work experimentally characterizes IPL of silver nanoparticle films. A newly observed turning point in the evolution of film temperature during IPL is correlated to the observation, in literature and in this work, that film densification levels off beyond a critical pulse fluence and number of pulses. A computational model is developed that couples electromagnetic finite element analysis, heat transfer models and densification models to predict the evolution of film temperature and density during IPL. This model is able to capture the experimentally observed turning point in temperature during IPL, whereas current models of IPL are unable to do so. It is shown that the temperature turning point occurs due to a coupling between optical absorption and densification in the nanoparticle film, mediated by a change in nanoscale shape of the deposited nanoparticles due to interparticle neck growth. Further, it is found that the optical fluence per pulse has a greater effect on the achievable film density in IPL, as compared to the number of pulses.

20.
Epidemiol Infect ; 144(6): 1267-77, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26482721

RESUMEN

Seasonal influenza is a significant public health concern globally. While influenza vaccines are the single most effective intervention to reduce influenza morbidity and mortality, there is considerable debate surrounding the merits and consequences of repeated seasonal vaccination. Here, we describe a two-season influenza epidemic contact network model and use it to demonstrate that increasing the level of continuity in vaccination across seasons reduces the burden on public health. We show that revaccination reduces the influenza attack rate not only because it reduces the overall number of susceptible individuals, but also because it better protects highly connected individuals, who would otherwise make a disproportionately large contribution to influenza transmission. We also demonstrate that our results hold on an empirical contact network, in the presence of assortativity in vaccination status, and are robust for a range of vaccine coverage and efficacy levels. Our work contributes a population-level perspective to debates about the merits of repeated influenza vaccination and advocates for public health policy to incorporate individual vaccine histories.


Asunto(s)
Inmunidad Colectiva , Inmunización Secundaria , Virus de la Influenza A/inmunología , Vacunas contra la Influenza/administración & dosificación , Gripe Humana/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Colombia Británica , Niño , Preescolar , Ciudades , Humanos , Lactante , Recién Nacido , Gripe Humana/inmunología , Persona de Mediana Edad , Modelos Teóricos , Salud Pública/tendencias , Estaciones del Año , Adulto Joven
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