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Gamma-ray bursts (GRBs) are flashes of high-energy radiation arising from energetic cosmic explosions. Bursts of long (greater than two seconds) duration are produced by the core-collapse of massive stars1, and those of short (less than two seconds) duration by the merger of compact objects, such as two neutron stars2. A third class of events with hybrid high-energy properties was identified3, but never conclusively linked to a stellar progenitor. The lack of bright supernovae rules out typical core-collapse explosions4-6, but their distance scales prevent sensitive searches for direct signatures of a progenitor system. Only tentative evidence for a kilonova has been presented7,8. Here we report observations of the exceptionally bright GRB 211211A, which classify it as a hybrid event and constrain its distance scale to only 346 megaparsecs. Our measurements indicate that its lower-energy (from ultraviolet to near-infrared) counterpart is powered by a luminous (approximately 1042 erg per second) kilonova possibly formed in the ejecta of a compact object merger.
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Estrellas CelestialesRESUMEN
Magnetars are strongly magnetized, isolated neutron stars1-3 with magnetic fields up to around 1015 gauss, luminosities of approximately 1031-1036 ergs per second and rotation periods of about 0.3-12.0 s. Very energetic giant flares from galactic magnetars (peak luminosities of 1044-1047 ergs per second, lasting approximately 0.1 s) have been detected in hard X-rays and soft γ-rays4, and only one has been detected from outside our galaxy5. During such giant flares, quasi-periodic oscillations (QPOs) with low (less than 150 hertz) and high (greater than 500 hertz) frequencies have been observed6-9, but their statistical significance has been questioned10. High-frequency QPOs have been seen only during the tail phase of the flare9. Here we report the observation of two broad QPOs at approximately 2,132 hertz and 4,250 hertz in the main peak of a giant γ-ray flare11 in the direction of the NGC 253 galaxy12-17, disappearing after 3.5 milliseconds. The flare was detected on 15 April 2020 by the Atmosphere-Space Interactions Monitor instrument18,19 aboard the International Space Station, which was the only instrument that recorded the main burst phase (0.8-3.2 milliseconds) in the full energy range (50 × 103 to 40 × 106 electronvolts) without suffering from saturation effects such as deadtime and pile-up. Along with sudden spectral variations, these extremely high-frequency oscillations in the burst peak are a crucial component that will aid our understanding of magnetar giant flares.
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Estrellas Celestiales , AtmósferaRESUMEN
Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4-13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.
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AIM: To assess the accuracy of Magnetic Resonance Index of Activity (MaRIA) in evaluating therapeutic efficacy in Crohn's disease (CD) patients with different activity levels using ileocolonoscopy as the reference standard. MATERIALS AND METHODS: Forty-eight patients underwent magnetic resonance enterography (MRE) and ileocolonoscopy at baseline, week 26, and week 52, along with the Simple Endoscopic Score for Crohn's Disease (SES-CD) and MaRIA scores. According to the SES-CD score at baseline, all patients were subdivided into mild, moderate, and severe activity subgroups. The identification of endoscopic mucosal healing (MH) was explored primarily. Moreover, the Crohn's Disease Activity Index (CDAI), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), procalcitonin (PCT), and interleukin-6 (IL-6) levels were collected and analysed. RESULTS: MaRIA correlated significantly with SES-CD and CRP at baseline, week 26, and week 52. The discrepancies in MaRIA and SES-CD were statistically significant before and after treatment. MaRIA = 24.43 and ΔMaRIA = 12.77 as the cut-off points were found to have high diagnostic accuracy for predicting MH. MaRIA (p<0.001), SES-CD (p<0.001), CRP (p<0.05), ESR (p<0.05), and CDAI score (p<0.05) in patients with MH were considerably decreased compared to those in patients without MH. CONCLUSIONS: MRE has good application value in evaluating the therapeutic response of CD patients treated with biological agents. MaRIA is a reliable indicator in the follow-up of CD patients, which is strongly correlated with SES-CD, and it has high accuracy in predicting endoscopic MH.
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Enfermedad de Crohn , Humanos , Enfermedad de Crohn/diagnóstico por imagen , Enfermedad de Crohn/tratamiento farmacológico , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Índice de Severidad de la EnfermedadRESUMEN
OBJECTIVE: The study was conducted to evaluate the effects of the absorbent (a mixture of activated carbon and hydrated sodium calcium aluminosilicate) on growth performance, blood profiles and hepatic genes expression in broilers fed diets naturally contaminated with aflatoxin. METHODS: A total of 1200 one-day-old male chicks were randomly assigned to 6 treatments with 10 replicate cages per treatment. The dietary treatments were as follows: (1) control (basal diets); (2) 50% contaminated corn; (3) 100% contaminated corn; (4) control + 1% adsorbent; (5) 50% contaminated corn + 1% absorbent; (6) 100% contaminated corn + 1% absorbent. RESULTS: During d 1 to 21, feeding contaminated diets reduced (p<0.05) body weight (BW), average daily gain (ADG) and average daily feed intake (ADFI), but increased (p<0.05) feed-to-gain ratio (F/G). The absorbent supplementation increased (p<0.05) BW, ADG and ADFI. There were interactions (p<0.05) in BW, ADG and ADFI between contaminated corn and absorbent. Overall, birds fed 100% contaminated diets had lower (p<0.05) final BW and ADG, but higher (p<0.05) F/G compared to those fed control diets. The absorbent addition increased (p<0.05) serum albumin concentration on d 14 and 28 and total protein (TP) level on d 28, decreased (p<0.05) alanine transaminase activity on d 14 and activities of aspartate aminotransferase and alkaline phosphatase on d 28. Feeding contaminated diets reduced (p<0.05) hepatic TP content on d 28 and 42. The contaminated diets upregulated (p<0.05) expression of interleukin-6, catalase (CAT) and superoxide dismutase (SOD), but downregulated (p<0.05) glutathione S-transferase (GST) expression in liver. The absorbent supplementation increased (p<0.05) interleukin-1ß, CAT, SOD, cytochrome P450 1A1 and GST expression in liver. There were interactions (p<0.05) in the expression of hepatic CAT, SOD and GST between contaminated corn and absorbent. CONCLUSION: The results suggest that the naturally aflatoxin-contaminated corn depressed growth performance, while the adsorbent could partially attenuate the adverse effects of aflatoxin on growth performance, blood profiles and hepatic genes expression in broilers.
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OBJECTIVE: This study was conducted to determine the effects of stale maize on growth performance, immunity, intestinal morphology, and antioxidant capacity in broilers. METHODS: A total of 800 one-day-old male Arbor Acres broilers (45.4±0.5 g) were blocked based on body weight, and then allocated randomly to 2 treatments with 20 cages per treatment and 20 broilers per cage in this 6-week experiment. Dietary treatments included a basal diet and diets with 100% of control maize replaced by stale maize. RESULTS: The content of fat acidity value was higher (p<0.05) while the starch, activities of catalase and peroxidase were lower (p<0.05) than the control maize. Feeding stale maize diets reduced (p<0.05) average daily feed intake (ADFI) throughout the experiment, feed conversion ratio (FCR) during d 0 to 21 and the whole experiment as well as relative weight of liver, spleen, bursa of Fabricius and thymus (p<0.05) on d 21. Feeding stale maize diets decreased jejunum villus height (VH) and VH/crypt depth (CD) (p<0.05) on d 21 and 42 as well as ileum VH/CD on d 42. The levels of immunoglobulin G, acid α-naphthylacetate esterase positive ratios and lymphocyte proliferation on d 21 and 42 as well as lysozyme activity and avian influenza antibody H5N1 titer on d 21 decreased (p<0.05) by the stale maize. Feeding stale maize diets reduced (p<0.05) serum interferon-γ, tumor necrosis factor-α, interleukin-2 on d 21 and interleukin-6 on d 21 and 42. Broilers fed stale maize diets had lower levels of (p<0.05) total antioxidative capacity on d 42, superoxide dismutase and glutathione peroxidase on d 21 and 42, but higher (p<0.05) levels of malondialdehyde on d 21 and 42. CONCLUSION: Feeding 100% stale maize decreased ADFI and FCR, caused adverse effects on immunity and antioxidant function and altered intestinal morphology in broilers.
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OBJECTIVE: A 28-d trial was conducted to evaluate the effect of diets with different energy and lipase levels on performance, nutrient digestibility, serum profiles, gut health, and carcass quality in broilers. METHODS: A total of 720 one-day-old male Ross 308 broilers (45.4±0.5 g) were randomly assigned to one of the following four treatments: i) RET, reduced energy treatment (metabolizable energy = 2,950 and 3,100 kcal/kg for starter and finisher diet), ii) BDT, basal diet treatment (metabolizable energy = 3,050 and 3,200 kcal/kg for starter and finisher diet, iii) RET015, RET+0.15 g/kg lipase, and iv) RET03, RET+0.3 g/kg lipase. There were 10 replications (cages) per treatment with 18 birds per cage. RESULTS: During d 1 to 14, broilers fed BDT, RET015, and RET03 diets had higher (p<0.05) body weight gain than those fed RET diet. During d 1 to 14, 15 to 28 and the overall experiment, feed conversion ratio in RET03 treatment was lower (p<0.05) compared with RET treatment. On d 14, the apparent total tract digestibility (ATTD) of dry matter (DM), ether extract (EE), and gross energy in RET03 treatment was higher (p<0.05) than those in RET treatment, while the ATTD of N was increased (p<0.05) by RET03 treatment. On d 28, broilers fed RET03 diet had higher (p<0.05) ATTD of DM than those fed RET and RET015 diets, while the ATTD of EE in BDT and RET03 treatments was increased (p<0.05) compared with RET and RET015 treatments. Broilers fed RET03 diet had higher villus height (VH) and VH:crypt depth (CD) ratio than those fed RET and BDT diets. The activity of pancreatic lipase in BDT and RET03 treatments was higher (p<0.05) than that in RET treatment. CONCLUSION: Taken together, lipase supplementation (3,000 U/kg feed) increased growth performance, nutrient digestibility, VH, VH:CD ratio and lipase activity, but decreased triglyceride, low-density lipoprotein cholesterol and the abdominal fat percentage in broilers fed reduced energy diet.
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The giant panda, Ailuropoda melanoleuca (Ursidae), has a unique bamboo-based diet; however, this low-energy intake has been sufficient to maintain the metabolic processes of this species since the fourth ice age. As mitochondria are the main sites for energy metabolism in animals, the protein-coding genes involved in mitochondrial respiratory chains, particularly cytochrome c oxidase subunit II (COX2), which is the rate-limiting enzyme in electron transfer, could play an important role in giant panda metabolism. Therefore, the present study aimed to isolate, sequence, and analyze the COX2 DNA from individuals kept at the Giant Panda Protection and Research Center, China, and compare these sequences with those of the other Ursidae family members. Multiple sequence alignment showed that the COX2 gene had three point mutations that defined three haplotypes, with 60% of the sequences corresponding to haplotype I. The neutrality tests revealed that the COX2 gene was conserved throughout evolution, and the maximum likelihood phylogenetic analysis, using homologous sequences from other Ursidae species, showed clustering of the COX2 sequences of giant pandas, suggesting that this gene evolved differently in them.
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Complejo IV de Transporte de Electrones/genética , Ursidae/genética , Animales , Metabolismo Energético/genética , Mitocondrias/genética , Mitocondrias/metabolismo , Ursidae/metabolismoRESUMEN
Objective: To explore a registry method for acute cardiovascular events in large-scale fields across China. Methods: This study was based on a community-based Kazakh cohort, including 1 668 persons with complete baseline data, conducted in Altay, Xinjiang. Acute cardiovascular events included acute myocardial infarction(ICD-10: I21-I22), sudden cardiac death (I46.1), and incident stroke (I60-I64) that occurred during the period from Oct 1, 2012 to Jun 30, 2016. There were three stages, a hospital-based search for checking medical records of inpatients in all four local hospitals, a community-based supplementary registry, and an extra survey for reducing false negatives, to complete this registry. The incidence referred to all events within one year per 100 000 people and mortality rate was the number of fatal events within 28 days per 100 000 people. The incidence and mortality was standardized with the weights from distribution of age and gender in the Sixth National Census of China. Results: Forty two cases with 46 acute cardiovascular events including 7 acute myocardial infarctions, 3 sudden cardiac deaths, and 36 incident strokes were found. The ratio of events was 3.6â¶1 for stroke and heart attacks and this ratio was 1.6â¶1 for ischemic or hemorrhagic strokes. A total of 28(60.9%) events and 18(39.1%) events were collected in the hospitals and by community-based supplementary registry physicians, respectively. False negatives were not found at the last stage. The crude and standardized incidence rates were 742 and 926 per 100 000 people and the related mortality rates were 194 and 272 per 100 000 people, respectively. Conclusion: Primary Care physicians are"net bottom" of a monitoring system which needs to combine preventive and clinical medicine with all kinds of governmental resources including health and social benefit.
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Infarto del Miocardio/epidemiología , Sistema de Registros , Accidente Cerebrovascular/epidemiología , China , Humanos , Incidencia , Proyectos PilotoRESUMEN
BACKGROUND: While oral antidepressants reach efficacy after weeks, single-dose intravenous (i.v.) ketamine has rapid, yet time-limited antidepressant effects. We aimed to determine the efficacy and safety of single-dose i.v. ketamine augmentation of escitalopram in major depressive disorder (MDD). METHOD: Thirty outpatients with severe MDD (17-item Hamilton Rating Scale for Depression total score ⩾ 24) were randomized to 4 weeks double-blind treatment with escitalopram 10 mg/day+single-dose i.v. ketamine (0.5 mg/kg over 40 min) or escitalopram 10 mg/day + placebo (0.9% i.v. saline). Depressive symptoms were measured using the Montgomery-Asberg Depression Rating Scale (MADRS) and the Quick Inventory of Depressive Symptomatology - Self-Report (QIDS-SR). Suicidal ideation was evaluated with the QIDS-SR item 12. Adverse psychopathological effects were measured with the Brief Psychiatric Rating Scale (BPRS)-positive symptoms, Young Mania Rating Scale (YMRS) and Clinician Administered Dissociative States Scale (CADSS). Patients were assessed at baseline, 1, 2, 4, 24 and 72 h and 7, 14, 21 and 28 days. Time to response (⩾ 50% MADRS score reduction) was the primary outcome. RESULTS: By 4 weeks, more escitalopram + ketamine-treated than escitalopram + placebo-treated patients responded (92.3% v. 57.1%, p = 0.04) and remitted (76.9% v. 14.3%, p = 0.001), with significantly shorter time to response [hazard ratio (HR) 0.04, 95% confidence interval (CI) 0.01-0.22, p < 0.001] and remission (HR 0.11, 95% CI 0.02-0.63, p = 0.01). Compared to escitalopram + placebo, escitalopram + ketamine was associated with significantly lower MADRS scores from 2 h to 2 weeks [(peak = 3 days-2 weeks; effect size (ES) = 1.08-1.18)], QIDS-SR scores from 2 h to 2 weeks (maximum ES = 1.27), and QIDS-SR suicidality from 2 to 72 h (maximum ES = 2.24). Only YMRS scores increased significantly with ketamine augmentation (1 and 2 h), without significant BPRS or CADSS elevation. CONCLUSIONS: Single-dose i.v. ketamine augmentation of escitalopram was safe and effective in severe MDD, holding promise for speeding up early oral antidepressant efficacy.
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Antidepresivos/administración & dosificación , Citalopram/administración & dosificación , Trastorno Depresivo Mayor/tratamiento farmacológico , Ketamina/administración & dosificación , Administración Intravenosa , Adolescente , Adulto , Antidepresivos/efectos adversos , China , Citalopram/efectos adversos , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Estimación de Kaplan-Meier , Ketamina/efectos adversos , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Inventario de Personalidad , Modelos de Riesgos Proporcionales , Escalas de Valoración Psiquiátrica , Autoinforme , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto JovenAsunto(s)
Trastornos Mentales , Enfermedades del Sistema Nervioso Periférico , Enfermedades de la Médula Espinal , Humanos , Óxido Nitroso/efectos adversos , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Investigación , Enfermedades de la Médula Espinal/inducido químicamente , Vitamina B 12/efectos adversosRESUMEN
The direction of production for indigenous chicken breeds is currently unknown and this knowledge, combined with the development of chicken genome-wide association studies, led us to investigate differences in specific loci between broiler and layer chicken using bioinformatic methods. In addition, we analyzed the distribution of these seven identified loci in four Chinese indigenous chicken breeds, Caoke chicken, Jiuyuan chicken, Sichuan mountain chicken, and Tibetan chicken, using DNA direct sequencing methods, and analyzed the data using bioinformatic methods. Based on the results, we suggest that Caoke chicken could be developed for meat production, while Jiuyuan chicken could be developed for egg production. As Sichuan mountain chicken and Tibetan chicken exhibited large polymorphisms, these breeds could be improved by changing their living environment.
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Cruzamiento , Pollos/genética , Polimorfismo de Nucleótido Simple/genética , Selección Genética , Animales , Pollos/fisiología , Huevos , Productos de la CarneRESUMEN
Gonadotropin-inhibitory hormone (GnIH) gene is an important gene in reproduction. In this study, we screened single-nucleotide polymorphisms (SNPs) in the chicken GnIH gene among 204 individuals in Erlang mountainous chickens. We then analyzed the associations between polymorphisms of the GnIH gene and 5 egg production traits in chickens. Five SNPs (T3305C, T3310C, G3403C, G3411A, and T3591C) were detected. Associations between polymorphic loci and age at first egg, body weight at first egg, weight at first egg, egg weight in 300 days, and egg production in 300 days were analyzed using analysis of covariance. The results showed that SNP1, SNP3, and SNP4 had large effects on age at first egg, while SNP5 had a large effect on body weight at first egg; of the effect of the TT genotype was significantly higher than that of CT (P < 0.01). Further analysis show that the highest frequency (0.2353) haplotype H1H1 was associated with the latest age at first egg. The H4H5 haplotype had a positive effect on egg production in 300 days and a negative effect on weight at first egg. We observed no association between the H3H3 haplotype and body weight at first egg.
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Proteínas Aviares/genética , Pollos/genética , Huevos , Estudios de Asociación Genética , Polimorfismo de Nucleótido Simple/genética , Alelos , Animales , Frecuencia de los Genes , Genotipo , Haplotipos/genética , Desequilibrio de Ligamiento/genética , Análisis de Secuencia de ADNRESUMEN
Artificial illumination is an important exogenous factor in the control of many physiological and behavioral processes as well as an important environmental factor in the management of laying hens. Melatonin receptors are members of the G protein-coupled receptor family. The hormone melatonin is secreted primarily by the pineal gland, with highest levels occurring during the dark period of a circadian cycle. The aim of this study was to examine the effect of monochromatic light on chicken egg reproduction and expression of melatonin receptors in chicken ovarian follicles. A total of 552 19-week-old hens were randomly divided into 4 groups with 138 birds in each group. Each group was randomly divided into 3 replicates with 46 birds in each replicate. Feed and water were provided for ad libitum. Light treatments were: control cool white (400-760 nm), blue (480 nm), green (560 nm), and red (660 nm). The short wavelength (blue light) group produced a greater total number of eggs at 300 days of age than did the long wavelength (red light) group, and the red light group showed higher melatonin receptor type 1A and melatonin receptor type 1C mRNA and protein expression. These results suggest that the wavelength of light is closely related to chicken egg number at 300 days of age; there is no effect of monochromatic light on melatonin receptor type 1B.
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Regulación de la Expresión Génica/efectos de la radiación , Luz , Folículo Ovárico/metabolismo , Receptores de Melatonina/genética , Animales , Pollos , Femenino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Melatonina/metabolismo , Reproducción/genética , Reproducción/efectos de la radiaciónRESUMEN
The National Health and Nutrition Examination Survey (NHANES) of America has been running for more than 60 years and has achieved many significant achievements with international influence. The application of modern information technologies in NHANES provides a supplementary tool for the project's high quality and refined implementation. This paper introduces the information system of NHANES from seven aspects: project management, survey participant interview, physical examination, laboratory examination, field follow-up, data sharing, and social services. The construction and application prospects of the China National Health Survey Information System, suitable for China's native conditions, are also discussed in this article.
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Sistemas de Información , Examen Físico , China , Humanos , Encuestas Nutricionales , Encuestas y CuestionariosRESUMEN
This study was conducted to determine the effect of methylsulfonylmethane (MSM) on growth performance, immune function, antioxidant capacity, and meat quality in Pekin ducks. A total of 960 female 1-day-old Pekin ducklings (53.3 ± 0.4 g) were randomly allotted to 3 treatments with 8 replicates of 40 birds, based on their body weight (BW). The experiment lasted 6 wks, and dietary treatments included a corn-soybean meal-based diet supplemented with 0%, 0.15%, and 0.3% MSM, that is, CON, MSM1, and MSM2, respectively. Growth performance, serum profiles, and meat quality were determined. During the period of days 22-42, BW gain (BWG) in MSM2 treatment was higher (P < 0.05) and feed-to-gain ratio (F/G) was lower (P < 0.05) than those of CON and MSM1 treatments. BW gain and final BW in MSM2 treatment were increased (P < 0.05) compared with CON and MSM1 treatments during the period of days 1-42. Serum activities of superoxide dismutase and glutathione peroxidase, total antioxidative capacity, and concentrations of interleukin-2 and interleukin-6 were higher (P < 0.05) in MSM2 than in CON treatment. Ducks in the MSM2 treatment group had lower (P < 0.05) serum malondialdehyde, interferon gamma, and tumor necrosis factor-α levels than those in the CON treatment group. The supplementation of MSM increased (P < 0.05) water-holding capacity and redness (a*) and decreased (P < 0.05) values for 2-thiobarbituric acid and drip loss on day 5. Ducks in the MSM2 treatment group had higher (P < 0.05) pH24h than those in the CON treatment group. Taken together, the inclusion of MSM (0.3%) increased final BW and BWG during periods of days 22-42 and days 1-42, reduced feed-to-gain ratio during the period of days 22-42, and resulted in positive effects on immunity, antioxidant capacity, and meat quality.
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Antioxidantes/metabolismo , Dimetilsulfóxido/metabolismo , Patos/fisiología , Carne/análisis , Sulfonas/metabolismo , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Suplementos Dietéticos/análisis , Dimetilsulfóxido/administración & dosificación , Relación Dosis-Respuesta a Droga , Patos/crecimiento & desarrollo , Patos/inmunología , Femenino , Distribución Aleatoria , Sulfonas/administración & dosificaciónRESUMEN
The present study was conducted to determine the impact of dietary energy and protein concentrations and lipid sources on growth performance and carcass traits of Pekin ducks. In Exp. 1, 15-day-old ducks (6 replicate pens, 60 ducks/pen) were randomly assigned to 4 dietary treatments with different metabolizable energy (ME) and crude protein (CP) concentrations (2,850 kcal/kg and 16%, 2,950 kcal/kg and 16.5%, 3,050 kcal/kg and 17.0%, and 3,150 kcal/kg and 17.5%) based on body weight (BW). In Exp. 2, 20-day-old ducks (4 replicate pens, 60 ducks/pen) were randomly allotted to 3 dietary fat sources (soybean oil, lard, and palm oil) with or without emulsifier in a 3 × 2 factorial arrangement. In Exp. 1, increasing ME and CP level improved (P < 0.05) body weight gain (BWG) and cost-to-gain ratio linearly, but reduced (P < 0.05) feed intake (FI) and feed-to-gain ratio (F/G) linearly. Breast skin thickness and liver redness (a*) value increased (P < 0.05) linearly with the increasing ME and CP level. In Exp. 2, no interactions between fat sources and emulsifier were observed. Feeding lard and palm oil diets increased (P < 0.05) final BW and BWG compared to soybean oil. Birds fed soybean oil and palm oil diets had lower (P < 0.05) FI compared to those fed lard diet. F/G in soybean oil and lard groups was higher (P < 0.05) compared to palm oil group. Birds in palm oil and lard groups had higher (P < 0.05) European production efficiency factor than those in soybean oil group. The addition of emulsifier increased (P < 0.05) BWG. In summary, the optimal ME and CP level for roasting was 2,950 kcal/kg ME and 16.5% CP and the palm oil was better than soybean oil and lard in Pekin ducks from 15 to 40 D of age.
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Proteínas en la Dieta/metabolismo , Patos/fisiología , Metabolismo Energético , Carne/análisis , Alimentación Animal/análisis , Animales , Culinaria , Dieta/veterinaria , Relación Dosis-Respuesta a Droga , Patos/crecimiento & desarrollo , Metabolismo Energético/efectos de los fármacos , Femenino , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Distribución AleatoriaRESUMEN
Double neutron star (DNS) merger events are promising candidates of short gamma-ray burst (sGRB) progenitors as well as high-frequency gravitational wave (GW) emitters. On August 17, 2017, such a coinciding event was detected by both the LIGO-Virgo gravitational wave detector network as GW170817 and Gamma-Ray Monitor on board NASA's Fermi Space Telescope as GRB 170817A. Here, we show that the fluence and spectral peak energy of this sGRB fall into the lower portion of the distributions of known sGRBs. Its peak isotropic luminosity is abnormally low. The estimated event rate density above this luminosity is at least [Formula: see text] Gpc-3 yr-1, which is close to but still below the DNS merger event rate density. This event likely originates from a structured jet viewed from a large viewing angle. There are similar faint soft GRBs in the Fermi archival data, a small fraction of which might belong to this new population of nearby, low-luminosity sGRBs.
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The cyclin-dependent kinase inhibitor p16INK4a encoded by the INK4A/CDKN2A/MTS1 gene is a frequent target of 9p21 inactivation in human lung cancers. The p14ARF transcript, which is an alternative spliced form of this locus, is also altered or deleted in a proportion of human lung cancers and has been shown to inhibit cell cycle progression as an endogenous cellular regulator of the p53 protein, raising the possibility that it might constitute an additional lung tumor suppressor gene at the 9p21 locus. To test the candidacy of p14ARF as a lung cancer suppressor and assess the role it plays in radiosensitivity, we transfected the wild-type p14ARF gene into four cell lines which had various endogenous gene backgrounds of INK4A-/p53+/RB+ (A549 and H460), INK4A+/p53+/RB- (H446) as well as p14ARF+/p53-/RB+ (Calu-1). We found that transfection of p14ARF is related to an obvious growth inhibition in all wtp53 cell lines, regardless of INK4A/ARF and RB status. Although it has been shown that p53-induced G1 checkpoint in response to DNA damage by ionizing radiation is p14ARF-independent, we found the radiosensitivity of two p14ARF-deficient cell lines was increased after p14ARF gene transfer. The results indicated that cell cycle redistribution after acquiring the exogenous gene might be the main explanation for the enhanced sensitization. An increased radiation-induced apoptotic proportion in one cell line also suggested a fortified p53 function that might be triggered by the restored p14ARF protein.
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Neoplasias Pulmonares/radioterapia , Proteínas/genética , Tolerancia a Radiación , Ciclo Celular/efectos de la radiación , División Celular , Supervivencia Celular/efectos de la radiación , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Genes Supresores de Tumor , Genes p53 , Terapia Genética , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteínas/fisiología , ARN Mensajero/análisis , Transfección , Células Tumorales Cultivadas , Ensayo de Tumor de Célula Madre , Proteína p14ARF Supresora de TumorRESUMEN
AIM: To study the SARs of 5,6-diaryl-2,3-dihydrol-1-pyrrolizinone derivatives to provide information for the design of new structural compounds. METHODS AND RESULTS: Three dimensional quantitative structure-activity relationship (3D-QSAR) model was constructed by Apex-3D. CONCLUSION: The antiinflammatory activities of 5, 6-diaryl-pyrrolizinones were related to the global hydrophobicity and volume, the properties of the group at 1-position of pyrrolizinone ring and the two secondary sites; improved the pi-electronic density of the group at 1-position of pyrrolizinone ring and lowered the global hydrophobicity and the volume of p-substituent of the phenyl ring at 6-position of pyrrolizinone contributed to the antiinflammatory activities of the title compounds.