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3.
Phys Rev E ; 109(2-2): 025204, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491565

RESUMO

In this work we present the design of the first controlled fusion laboratory experiment to reach target gain G>1 N221204 (5 December 2022) [Phys. Rev. Lett. 132, 065102 (2024)10.1103/PhysRevLett.132.065102], performed at the National Ignition Facility, where the fusion energy produced (3.15 MJ) exceeded the amount of laser energy required to drive the target (2.05 MJ). Following the demonstration of ignition according to the Lawson criterion N210808, experiments were impacted by nonideal experimental fielding conditions, such as increased (known) target defects that seeded hydrodynamic instabilities or unintentional low-mode asymmetries from nonuniformities in the target or laser delivery, which led to reduced fusion yields less than 1 MJ. This Letter details design changes, including using an extended higher-energy laser pulse to drive a thicker high-density carbon (also known as diamond) capsule, that led to increased fusion energy output compared to N210808 as well as improved robustness for achieving high fusion energies (greater than 1 MJ) in the presence of significant low-mode asymmetries. For this design, the burnup fraction of the deuterium and tritium (DT) fuel was increased (approximately 4% fuel burnup and a target gain of approximately 1.5 compared to approximately 2% fuel burnup and target gain approximately 0.7 for N210808) as a result of increased total (DT plus capsule) areal density at maximum compression compared to N210808. Radiation-hydrodynamic simulations of this design predicted achieving target gain greater than 1 and also the magnitude of increase in fusion energy produced compared to N210808. The plasma conditions and hotspot power balance (fusion power produced vs input power and power losses) using these simulations are presented. Since the drafting of this manuscript, the results of this paper have been replicated and exceeded (N230729) in this design, together with a higher-quality diamond capsule, setting a new record of approximately 3.88MJ of fusion energy and fusion energy target gain of approximately 1.9.

4.
Phys Rev E ; 109(2-2): 025203, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491694

RESUMO

An indirect-drive inertial fusion experiment on the National Ignition Facility was driven using 2.05 MJ of laser light at a wavelength of 351 nm and produced 3.1±0.16 MJ of total fusion yield, producing a target gain G=1.5±0.1 exceeding unity for the first time in a laboratory experiment [Phys. Rev. E 109, 025204 (2024)10.1103/PhysRevE.109.025204]. Herein we describe the experimental evidence for the increased drive on the capsule using additional laser energy and control over known degradation mechanisms, which are critical to achieving high performance. Improved fuel compression relative to previous megajoule-yield experiments is observed. Novel signatures of the ignition and burn propagation to high yield can now be studied in the laboratory for the first time.

5.
Hong Kong Med J ; 29(4): 295-300, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37496328

RESUMO

INTRODUCTION: This study evaluated risk factors for postpartum haemorrhage (PPH) in twin pregnancies, particularly factors associated with major PPH (blood loss of >1000 mL), to facilitate identification of high-risk twin pregnancies. METHODS: This retrospective cohort study included all women with twin pregnancies who delivered at a tertiary obstetric unit in Hong Kong from 2009 to 2018 and experienced PPH (blood loss of ≥500 mL). Postpartum haemorrhage was classified using three thresholds for blood loss volume: ≥500 mL (all PPH), >1000 mL (major PPH), and >1500 mL (severe PPH). Risk factors for each threshold of PPH were analysed. RESULTS: In total, there were 680 twin pregnancies. The overall incidence of all PPH (≥500 mL) in this cohort was 27.8%, including minor PPH (500-1000 mL, 20.1%), major but not severe PPH (1001-1500 mL, 4.4%), and severe PPH (>1500 mL, 3.2%). Logistic regression analysis showed that general anaesthesia and the use of oxytocin were significant risk factors for all PPH (≥500 mL); general anaesthesia, in vitro fertilisation, antepartum haemorrhage, placental abruption, and placenta praevia were significant risk factors for major PPH (>1000 mL); in vitro fertilisation, placenta praevia, and obesity were significant risk factors for severe PPH (>1500 mL). CONCLUSION: Women with twin pregnancies who have obesity, conception by in vitro fertilisation, or placenta praevia exhibit a high risk of severe PPH. They should deliver in obstetric units with readily available blood product transfusions and the appropriate expertise for prompt management of severe PPH.


Assuntos
Hemorragia Pós-Parto , Gravidez de Gêmeos , Fatores de Risco , Hemorragia Pós-Parto/epidemiologia , Hemorragia Pós-Parto/prevenção & controle , Hemorragia Pós-Parto/terapia , Feminino , Gravidez , Índice de Gravidade de Doença , Estudos Retrospectivos , Obesidade/epidemiologia , Fertilização in vitro , Placenta Prévia/epidemiologia , Transfusão de Sangue , Humanos , Adolescente , Adulto Jovem , Adulto
6.
Zhonghua Jie He He Hu Xi Za Zhi ; 46(7): 708-711, 2023 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-37402662

RESUMO

Pulmonary embolism (PE) is one of the leading causes of maternal death. Various clinical and environmental risk factors can cause PE. Here, we reported an uncommon PE case with multiple etiological causes, including caesarean section, overweight, anti-cardiolipin antibody positive, and factor 5 gene mutation. The patient was a 25-year-old woman who developed cardiac asystole and apnea one day after cesarean delivery due to pulmonary embolism. After cardiopulmonary resuscitation and thrombolytic therapy, high doses of epinephrine were still needed to maintain blood pressure and heart rate, so we treated her with venoarterial extracorporeal membrane oxygenation (ECMO) to maintain systemic circulation. She progressively improved and was discharged on oral warfarin treatment. Comprehensive laboratory tests revealed a positive anticardiolipin antibody. Through whole exon gene sequencing, we identified a novel mutation (A2032➝G) in the F5 gene. This mutation was predicted to result in the replacement of lysine with glutamate at position 678, close to one of the APC cleavage sites. P.Lys678Glu was found to be a detrimental mutation by SIFT software and suspected detrimental by Polyphen-2 software. Attention should be paid to the etiological screening of young patients with pulmonary embolism, which is helpful in guiding the anticoagulant scheme and anticoagulant duration, and is of great significance in preventing thrombosis recurrence and complications.


Assuntos
Cesárea , Embolia Pulmonar , Humanos , Gravidez , Feminino , Adulto , Embolia Pulmonar/diagnóstico , Anticoagulantes , Período Pós-Parto , Mutação
7.
Zhonghua Yi Xue Za Zhi ; 103(15): 1119-1126, 2023 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-37055229

RESUMO

Objective: To present efficacy of clinical application of a classification based on crucial curvature of coronal imbalance in degenerative lumbar scoliosis (DLS). Methods: A case series study. Clinical data of 61 cases (8 males, 53 females) who underwent posterior correction surgery for DLS from January 2019 to January 2021 were retrospectively analyzed. The mean age was (71.7±6.2) years (ranged 60-82 years). According to the direction of C7 plumb line (C7PL) deviated from central sacral vertical line (CSVL) and orientation of L4 coronal tilt, the author determined which one was the crucial curve. If C7PL deviated from CSVL in the same direction as concave side of the thoracolumbar curve and L4 coronally tilts opposite direction of C7PL deviates from CSVL, then the crucial curve was thoracolumbar curve (type 1). On the contrary, if C7PL deviated from CSVL in the same direction as concave side of the lumbosacral curve and L4 coronally tilts consist with direction of C7PL deviates from CSVL, then the crucial curve was lumbosacral curve (type 2). According to absolute value of coronal balance distance (|CBD|), each type of patients was divided into two groups, respectively, namely coronal balance (CB) (|CBD|≤3 cm) and coronal imbalance (CIB) (|CBD|>3 cm). Changes of Cobb angles of thoracolumbar curve and lumbosacral curve and CBD were recorded and analyzed. Results: The rate of preoperative CIB was 55.7% (34/61) in all the patients. Of the patients, 23 cases were classified as type 1 and 38 cases as type 2. The rate of preoperative CIB was 34.8% (8/23) in type 1 patients and 68.4% (26/38) in type 2. The rate of postoperative CIB was 27.9% (17/61) in all the patients, with 13.0% (3/23) in type 1 and 36.8% (14/38) in type 2. The |CBD| of CB group in type 1 patients decreased from (2.6±1.4) cm before the operation to (1.5±1.0) cm after (P=0.015); and the correction rate of thoracolumbar curve (68.8%±18.4%) was significantly higher than that of lumbosacral curve (34.5%±23.9%) (P=0.005). The |CBD| of CB group in type 2 patients decreased from (2.6±3.0) cm before the operation to (1.6±1.2) cm after (P=0.027); the correction rate of lumbosacral curve (71.3%±18.6%) was higher than that of thoracolumbar curve (57.3%±21.1%), but the difference was not statistically significant (P=0.546). There was no significant difference in |CBD| of CIB group in type 2 patients before and after the operation (P=0.222); the correction rate of lumbosacral curve (38.3%±14.8%) was significantly lower than that of thoracolumbar curve (53.6%±16.0%) (P=0.001). There was a correlation between the change of CBD (3.8±1.5) cm and the difference in correction rate between thoracolumbar and lumbosacral curve (32.3%±19.6%) in CB group in type 1 patients after surgery (r=0.904, P<0.001). There was a correlation between the change of CBD (1.9±2.2) cm and the difference in correction rate between lumbosacral and thoracolumbar curve (14.0%±26.2%) in CB group in type 2 patients after surgery (r=0.960, P<0.001). Conclusion: Clinical application of a classification based on crucial curvature of coronal imbalance in DLS is satisfactory, and its combination with matching correction can effectively prevent the occurrence of coronal imbalance after spinal correction surgery.


Assuntos
Escoliose , Fusão Vertebral , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Escoliose/cirurgia , Estudos Retrospectivos , Período Pós-Operatório , Sacro , Vértebras Lombares/cirurgia , Resultado do Tratamento , Vértebras Torácicas/cirurgia
8.
Poult Sci ; 102(4): 102505, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36739804

RESUMO

This study aimed to examine the influence of dietary CP on the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of amino acids (AA) and test the additivity of AA digestibility in corn-soybean meal-based diets fed to broilers. Six experimental diets comprising a nitrogen-free diet and five corn-soybean meal-based diets containing 6.0%, 9.5%, 13.0%, 16.5%, and 20.0% CP were prepared. Increments in CP and AA concentrations were achieved by increasing the inclusion rate of corn and soybean meal at the expense of cornstarch. All diets contained 0.5% chromic oxide, which was included as an indigestible index. A total of 960 Ross 308 male broilers 19-day-old male broilers (Ross 308), with a mean BW of 628 g (SD = 58.0), were allocated to six dietary treatment groups in a randomized complete block design, with each treatment group have eight replicate cages and 20 birds per cage. All birds were fed the experimental diets for 4 days. On d 23, individual BW and feed intake were recorded, followed by collection of ileal digesta samples from the distal ileum. Regarding growth, the final BW, weight gain, feed intake, and gain to feed ratio increased linearly (P < 0.001) as dietary CP concentrations increased. With the increase in dietary CP concentrations from 6.0% to 20.0%, the AID of all AA, except Arg, increased linearly (P < 0.05). However, the SID of all AA, except Arg, Cys, and Pro, remained unaffected by CP concentrations in the diets. This study indicated that dietary CP concentrations from 6.0% to 20.0% have an effect on the growth performance of birds and the AID of most AA; however, the SID of most AA was not affected by dietary CP concentrations in the corn-soybean meal-based diets. In conclusion, the SID of AA is more additive than the AID of AA in poultry diets containing CP in the range of 6.0% to 20.0%.


Assuntos
Aminoácidos , Galinhas , Masculino , Animais , Aminoácidos/metabolismo , Galinhas/metabolismo , Zea mays/metabolismo , Digestão , Glycine max/química , Farinha , Íleo/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Dieta/veterinária , Proteínas Alimentares/metabolismo
9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(1): 52-57, 2023 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-36655258

RESUMO

The participants in this study were 20-49 years old rural childbearing age people who received the National Free Preconception Health Examination Project (NFPHEP) in Yunnan Province during 2013 to 2019. The proportion of ABO and RhD blood groups among different ethnic groups and different areas were calculated. The proportion of 2 748 131 participants with blood group A phenotype was highest (32.60%), followed by O (30.60%), B (27.33%) and AB (9.47%). In the RhD blood system, the proportion of the RhD positivity (RhD+) and RhD negativity (RhD-) group were 99.29% and 0.71% respectively. The proportions blood groups were significantly different among ethnic groups and areas (all P<0.001). Among 18 ethnic groups with more than 3 000 participants, Yao (42.75%), Bouyei (40.58%) and Dai (40.37%) ethnic groups had higher proportion of blood group O phenotype than other ethnic groups. Wa ethnic groups had highest proportion of the A (40.15%) and AB phenotypes (11.23%). Miao ethnic group (34.70%) and Lahu ethnic group (34.42%) had higher proportion of blood group B phenotype than other ethnic groups. Wa ethnic group had the highest proportion of RhD-group (1.88%). In all 16 prefectures of Yunnan, the proportion of blood group O phenotype was highest in Xishuangbanna Dai Autonomous Prefecture (40.27%). Baoshan city (36.39%), Lincang city (36.22%) and Dali Bai autonomous prefecture (36.06%) had higher proportion of blood group A phenotype than other regions. Diqing Tibetan Autonomous Prefecture (30.83%) and Qujing city (30.48%) had higher proportion of blood group B phenotype than other areas, while Zhaotong city had a highest proportion of blood group AB phenotype (11.19%). The proportion of RhD-group was highest in Honghe hani and Yi nationality autonomous prefecture(1.37%). The A RhD+(39.36%), A RhD-(0.78%), AB RhD+(11.03%), AB RhD-(0.20%) and O RhD-(0.48%) blood groups were higher proportion in Wa ethnic group than in other ethnic groups (P<0.001).


Assuntos
Antígenos de Grupos Sanguíneos , Adulto , Humanos , Pessoa de Meia-Idade , Adulto Jovem , China , Etnicidade , População Rural
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