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1.
Nature ; 565(7741): 581-586, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30700868

RESUMO

Focusing laser light onto a very small target can produce the conditions for laboratory-scale nuclear fusion of hydrogen isotopes. The lack of accurate predictive models, which are essential for the design of high-performance laser-fusion experiments, is a major obstacle to achieving thermonuclear ignition. Here we report a statistical approach that was used to design and quantitatively predict the results of implosions of solid deuterium-tritium targets carried out with the 30-kilojoule OMEGA laser system, leading to tripling of the fusion yield to its highest value so far for direct-drive laser fusion. When scaled to the laser energies of the National Ignition Facility (1.9 megajoules), these targets are predicted to produce a fusion energy output of about 500 kilojoules-several times larger than the fusion yields currently achieved at that facility. This approach could guide the exploration of the vast parameter space of thermonuclear ignition conditions and enhance our understanding of laser-fusion physics.

2.
Phys Rev Lett ; 133(9): 095101, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39270173

RESUMO

We show that an x-ray emission signature associated with acceleration phase mass injection [R. C. Shah et al., Phys. Rev. E 103, 023201 (2021)PRESCM2470-004510.1103/PhysRevE.103.023201] correlates with poor experimental hot-spot convergence and a reduced neutron production relative to expectations. It is shown that with increased target mass as well as with higher-design adiabats, this signature is reduced, whereas with increased debris on the target, the signature is increased. We estimate that the vapor region in typical best designs may have up to 2× the assumed hydrogen mass at the start of deceleration.

3.
Tech Coloproctol ; 28(1): 89, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085710

RESUMO

BACKGROUND: Fistula-tract laser closure (FiLaC™) has shown promising outcomes in perianal fistulizing Crohn's disease (pfCD). However, most studies assessed a mixed cohort encompassing pfCD and cryptoglandular fistulas during a short follow-up period. This study aimed to evaluate the long-term treatment outcomes of FiLaC™ in patients with complex pfCD. METHODS: Data from patients with complex pfCD who underwent FiLaC™ during deep remission of Crohn's disease between January 2019 and December 2020 were retrospectively analyzed. Patient demographics, surgery history, and medication strategy were registered before surgery. Follow-ups were scheduled at 1, 2, and 3 months after FiLaC™, and at 2-month intervals thereafter. The primary endpoint was clinic healing, while clinic remission/unhealed/recurrence were classified as unhealed. Additionally, adverse events and Wexner fecal incontinence score were documented. RESULTS: Forty-nine patients (40 men and 9 women) with a median age of 26.0 (19.0-35.5) years were included with a median follow-up of 50.0 (39.5-54.0) months. Of these, 31 (63.3%) patients achieved fistula healing, 3 (6.1%) experienced improvement, 3 (6.1%) remained unhealed, and 12 (24.5%) experienced recurrence. Montreal A category was lower in the healed group (P < 0.001). No major complications, such as bleeding or fecal or urinary incontinence, were observed, and pain was transient. The Wexner incontinence score decreased significantly at the last available follow-up, indicating an intact postoperative continence function (P = 0.014). PCDAI scores were significantly higher in the unhealed group (P = 0.041). CONCLUSION: FiLaC™ is an efficient and safe sphincter-saving procedure for patients with complex pfCD.


Assuntos
Doença de Crohn , Terapia a Laser , Fístula Retal , Humanos , Doença de Crohn/complicações , Fístula Retal/etiologia , Fístula Retal/cirurgia , Feminino , Masculino , Adulto , Estudos Retrospectivos , Resultado do Tratamento , Terapia a Laser/métodos , Adulto Jovem , Recidiva , Seguimentos , Incontinência Fecal/etiologia , Incontinência Fecal/cirurgia , Cicatrização , Fatores de Tempo
4.
Zhonghua Fu Chan Ke Za Zhi ; 59(1): 64-69, 2024 Jan 25.
Artigo em Zh | MEDLINE | ID: mdl-38228517

RESUMO

Objective: To evaluate the incidence, treatment, and survival outcomes of Swyer syndrome with gonadal non-dysgerminoma malignant germ cell tumor (MGCT-NDG). Methods: A retrospective study was performed on Swyer syndrome patients with MGCT-NDG between January 2011 and December 2022 in Peking Union Medical College Hospital to investigate their characteristics and outcomes. Results: A total of 15 patients (4.9%, 15/307) with Swyer syndrome were identified in 307 MGCT-NDG patients. The average age at diagnosis of MGCT-NDG and Swyer syndrome were (16.8±6.7) and (16.7±6.6) years, respectively. Six cases were preoperatively diagnosed as Swyer syndrome, of which 4 cases received bilateral gonadectomy with or without hysterectomy, while the other 2 cases underwent removal of gonadal tumor and unilateral gonadectomy with hysterectomy, respectively. Of the 9 patients postoperatively diagnosed as Swyer syndrome, unilateral gonadectomy, removal of gonadal tumor, and unilateral gonadectomy with hysterectomy were performed in 6 patients, 2 patients, and 1 patient, respectively. Mixed malignant germ cell tumor (MGCT;10 cases), yolk sac tumor (4 cases), and immature teratoma (1 case) were the pathological subtypes, in the descending order. There were International Federation of Gynecology and Obstetrics (FIGO) stage Ⅰ in 6 cases, stage Ⅱ in 3 cases, stage Ⅲ in 5 cases, and stage Ⅳ in 1 case, respectively. Eleven patients received reoperation for residual gonadectomy after a average delay of (7.9±6.2) months, including 8 MGCT-NDG patients and 1 gonadoblastoma patient, no tumor involved was seen in the remaining gonads in the other 2 cases. Ten patients experienced at least one recurrence, with a median event free survival of 9 months (5, 30 months), of which 2 patients received surgery only at the time of initial treatment. All patients with recurrence received surgery and combined with postoperative chemotherapy. After a median follow-up of 25 months (15, 42 months), 10 patients were disease-free, 3 patients died of the tumor, 1 died of side effects of leukemia chemotherapy, and 1 survived with disease. Conclusion: The incidence rate of Swyer syndrome in patients with MGCT-NDG is about 4.9%; timely diagnosis and bilateral gonadectomy should be emphasized to reduce the risk of reoperation and second carcinogenesis in this population.


Assuntos
Disgenesia Gonadal 46 XY , Gonadoblastoma , Neoplasias Embrionárias de Células Germinativas , Neoplasias Ovarianas , Feminino , Humanos , Estudos Retrospectivos , Disgenesia Gonadal 46 XY/diagnóstico , Disgenesia Gonadal 46 XY/patologia , Disgenesia Gonadal 46 XY/cirurgia , Gonadoblastoma/patologia , Gonadoblastoma/cirurgia , Neoplasias Embrionárias de Células Germinativas/cirurgia , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/cirurgia , Neoplasias Ovarianas/patologia
5.
Zhonghua Fu Chan Ke Za Zhi ; 59(3): 200-209, 2024 Mar 25.
Artigo em Zh | MEDLINE | ID: mdl-38544449

RESUMO

Objective: To evaluate the surgery combined chemotherapy and radiation in locally advanced neuroendocrine carcinoma of the cervix (NECC) . Methods: This is a single-center retrospective cohort study. Locally advanced NECC patients admitted to Peking Union Medical College Hospital, Chinese Acadmy of Medical Sciences from January 2011 to April 2022 were enrolled. They were divided into concurrent chemoradiotherapy group, and surgery combined with chemotherapy and radiation group. The Kaplan-Meier method was used to analyze the progression free survival (PFS), overall survival (OS), recurrence rate, and mortality rate. Results: (1) Forty-six cases were included, 22 in concurrent chemoradiotherapy group, 24 in surgery combined chemotherapy and radiation group. With 16 patients (35%, 16/46) received neoadjuvant chemotherapy (NACT), the NACT effective rate was 15/16. (2) The median follow-up time was 27.5 months (range: 10-106 months), with 26 (57%, 26/46) experienced recurrences. There were 4 (9%, 4/46) pelvic recurrences and 25 (54%, 25/46) distant recurrences, and 3 (7%, 3/46) both pelvic and distant recurrences. Compared with concurrent chemoradiotherapy group, surgery combined chemotherapy and radiation group had lower pelvic recurrence rate [14% (3/22) vs 4% (1/24); χ2=1.296, P=0.255] but without statistic difference. Both groups had similar distant recurrence rate [55% (12/22) vs 54% (13/24); χ2=0.001, P=0.979] and overall recurrence rate [59% (13/22) vs 54% (13/24); χ2=0.113, P=0.736]. (3) During the follow-up period, 22 cases (48%, 22/46) died, with 11 cases (50%, 11/22) in concurrent chemoradiotherapy group and 11 cases (46%, 11/24) in surgery combined chemotherapy and radiation group, without significant difference (χ2=0.080, P=0.777). The postoperative 3-year and 5-year OS rates were 62.3% and 36.9%. Compared with concurrent chemoradiotherapy group, the patients in surgery combined chemotherapy and radiation group showed an extended trend in PFS (17.0 vs 32.0 months) and OS (37.0 vs 50.0 months) but without statistic differences (P=0.287, P=0.125). Both groups had similar 3-year OS rate (54.2% vs 69.9%; P=0.138) and 5-year OS rate (36.1% vs 38.8%; P=0.217). Conclusions: Our study supports the multi-modality treatment strategy (including surgery, chemotherapy and radiation) as an important component in the treatment of locally advanced NECC. The combination of surgery, chemotherapy and radiation seems to have advantages in the treatment of locally advanced NECC, but needs to be confirmed by further multicenter studies.


Assuntos
Carcinoma Neuroendócrino , Colo do Útero , Feminino , Humanos , Resultado do Tratamento , Estudos Retrospectivos , Quimiorradioterapia , Terapia Neoadjuvante , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Neuroendócrino/cirurgia , Estadiamento de Neoplasias
6.
Phys Rev Lett ; 131(10): 105101, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739360

RESUMO

In direct-drive inertial confinement fusion, the laser bandwidth reduces the laser imprinting seed of hydrodynamic instabilities. The impact of varying bandwidth on the performance of direct-drive DT-layered implosions was studied in targets with different hydrodynamic stability properties. The stability was controlled by changing the shell adiabat from (α_{F}≃5) (more stable) to (α_{F}≃3.5) (less stable). These experiments show that the performance of lower adiabat implosions improves considerably as the bandwidth is raised indicating that further bandwidth increases, beyond the current capabilities of OMEGA, would be greatly beneficial. These results suggest that the future generation of ultra-broadband lasers could enable achieving high convergence and possibly high gains in direct drive ICF.

7.
Zhonghua Fu Chan Ke Za Zhi ; 58(9): 680-690, 2023 Sep 25.
Artigo em Zh | MEDLINE | ID: mdl-37724385

RESUMO

Objective: To evaluate the effect of postoperative radiotherapy and high-risk pathological factors on the prognosis of early-stage neuroendocrine carcinoma of cervix (NECC). Methods: A single-center retrospective cohort study of early-stage NECC in Peking Union Medical College Hospital from January 2011 to April 2022 were enrolled. The patients were treated with radical hysterectomy±adjuvant treatment. They were divided into postoperative non-radiation group and postoperative radiation group. The possible postoperative recurrence risk factors identified by univariate analysis were assessed using multivariate logistic regression. The Kaplan-Meier method was used to analyze the progression free survival (PFS), overall survival (OS), recurrence rate, and mortality rate. Results: (1) Sixty-two cases were included in the study, including 33 cases in postoperative non-radiation group and 29 cases in postoperative radiation group. (2) The median follow-up time was 37 months (ranged 12-116 months), with 23 cases (37%) experienced recurrences. There were 7 cases (11%) pelvic recurrences and 20 cases (32%) distant recurrences, in which including 4 cases (6%) both pelvic and distant recurrences. Compared with postoperative non-radiation group, the postoperative radiation group had a lower pelvic recurrence rate (18% vs 3%; P=0.074) but without statistic difference, a slightly elevated distant recurrence rate (24% vs 41%; P=0.150) and overall recurrence rate (33% vs 41%; P=0.513) without statistically significances. Univariate analysis showed that lymph-vascular space invasion and the depth of cervical stromal invasion≥1/2 were risk factors for postoperative recurrence (all P<0.05). Multivariate analysis showed lymph-vascular space invasion was an independent predictor for postoperative recurrence (OR=23.03, 95%CI: 3.55-149.39, P=0.001). (3) During the follow-up period, 18 cases (29%, 18/62) died with tumor, with 10 cases (30%, 10/33) in postoperative non-radiation group and 8 cases (28%, 8/29) in postoperative radiation group, without significant difference (P=0.814). The postoperative 3-year and 5-year survival rate was 79.2%, 60.8%. The depth of cervical stromal invasion≥1/2 was more common in postoperative radiation group (27% vs 64%; P=0.011), and postoperative radiation in such patients showed an extended trend in PFS (32.3 vs 53.9 months) and OS (39.4 vs 73.4 months) but without statistic differences (P=0.704, P=0.371). Compared with postoperative non-radiation group, the postoperative radiation did not improve PFS (54.5 vs 37.3 months; P=0.860) and OS (56.2 vs 62.4 months; P=0.550) in patients with lymph-vascular space invasion. Conclusions: Postoperative radiation in early-stage NECC patients has a trend to reduce pelvic recurrence but not appear to decrease distant recurrence and overall recurrence, and has not improved mortality. For patients with the depth of cervical stromal invasion≥1/2, postoperative radiation has a trend of prolonging OS and PFS but without statistic difference. Lymph-vascular space invasion is an independent predictor for postoperative recurrence, but postoperative radiation in such patients does not seem to have any survival benefits.


Assuntos
Carcinoma Neuroendócrino , Neoplasias do Colo do Útero , Feminino , Humanos , Colo do Útero/cirurgia , Prognóstico , Estudos Retrospectivos , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia , Carcinoma Neuroendócrino/radioterapia , Carcinoma Neuroendócrino/cirurgia , Recidiva
8.
Zhonghua Wai Ke Za Zhi ; 61(8): 727-732, 2023 Aug 01.
Artigo em Zh | MEDLINE | ID: mdl-37400216

RESUMO

Proximal tibial aspect ratio (PTAR) is closely related to age, disease status and cutting parameters with considerable inter-individual variation independent of gender and race, nevertheless the aspect ratio of tibial components from different manufacturers remains relatively constant from smallest to largest size. As a result, component mismatching is an unavoidable dilemma during tibia preparation in total knee arthroplasty (TKA). Various prosthesis systems all can achieve more than 80% coverage on proximal tibia, whereas their optimal fit rates are generally not more than 50%. It is difficult for symmetrical components to avoid anteroposterior mismatch, internal malrotation tends to occur when maximum coverage is pursued on the resected surface with a medial dominant plateau or lower PTAR. Although it is easier to achieve a balance of rotation and coverage with anatomical components, significant anteromedial overhang tends to appear on the resected surface with a symmetrical or lateral dominant plateau. Further researches should focus on the law of inter-individual variability of proximal tibial morphology, the quantitative definition of "ideal matching" safety zone of key morphological parameters on different areas of proximal tibia and the methodology of realizing"ideal matching"in the majority patients with the least amount of component sizes. In addition, with the rapid development of additive manufacturing and digital orthopedic technology, individual customized implant is expected to become a breakthrough point in the field of TKA component fitting.

9.
Phys Rev Lett ; 129(9): 095001, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36083671

RESUMO

Spherical implosions in inertial confinement fusion are inherently sensitive to perturbations that may arise from experimental constraints and errors. Control and mitigation of low-mode (long wavelength) perturbations is a key milestone to improving implosion performances. We present the first 3D radiation-hydrodynamic simulations of directly driven inertial confinement fusion implosions with an inline package for polarized crossed-beam energy transfer. Simulations match bang times, yields (separately accounting for laser-induced high modes and fuel age), hot spot flow velocities and direction, for which polarized crossed-beam energy transfer contributes to the systematic flow orientation evident in the OMEGA implosion database. Current levels of beam mispointing, imbalance, target offset, and asymmetry from polarized crossed-beam energy transfer degrade yields by more than 40%. The effectiveness of two mitigation strategies for low modes is explored.

10.
Clin Radiol ; 77(8): e576-e584, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35469666

RESUMO

AIM: To assess whether conventional magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), and dynamic susceptibility contrast-enhanced perfusion-weighted imaging (DSC-PWI) could non-invasively predict p53 and Ki-67 labelling index (LI) and O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status in adult isocitrate dehydrogenase (IDH) wild-type glioblastomas. METHODS: The conventional MRI, DWI, and DSC-PWI results of 120 adult patients with IDH wild-type glioblastomas were reviewed retrospectively and their efficacy was analysed using chi-square tests or Fisher's exact test. Relative minimum apparent diffusion coefficient (rADCmin) and relative maximum cerebral blood volume (rCBVmax) values were compared between glioblastomas with different molecular statuses using the Mann-Whitney U-test. Receiver operating characteristic (ROC) curves and logistic regression were used to evaluate predictive performance. RESULTS: Glioblastomas with a high p53 LI were more likely to show a well-defined enhancement margin (p=0.047). Glioblastomas in the high-Ki-67-LI group demonstrated significantly lower rADCmin (p<0.001) and higher rCBVmax (p=0.001) values than those in the low-Ki-67-LI group. Tumours without MGMT promoter methylation showed lower rADCmin (p<0.001) and higher rCBVmax (p<0.001) values than those with it. The rCBVmax value exhibited a greater efficacy in predicting the MGMT promoter methylation status of adult IDH wild-type glioblastomas than the rADCmin value (p=0.001). CONCLUSIONS: The present results suggest that conventional and DWI and DSC-PWI results are influenced by the molecular status of the glioblastoma and indicate that DWI and DSC-PWI may help to identify regions of high invasiveness within heterogeneous glioblastomas.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Adulto , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , DNA , Glioblastoma/diagnóstico por imagem , Glioblastoma/genética , Glioblastoma/patologia , Guanina/análogos & derivados , Humanos , Isocitrato Desidrogenase/genética , Antígeno Ki-67 , Imageamento por Ressonância Magnética/métodos , Metilação , O(6)-Metilguanina-DNA Metiltransferase/genética , Perfusão , Estudos Retrospectivos , Proteína Supressora de Tumor p53/genética
11.
Chaos ; 32(3): 033110, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35364840

RESUMO

In addition to inhibitory interneurons, there exist excitatory interneurons (EINs) in the cortex, which mainly have excitatory projections to pyramidal neurons. In this study, we improve a thalamocortical model by introducing EIN, investigate the dominant role of EIN in generating spike and slow wave discharges (SWDs), and consider a non-rectangular pulse to control absence seizures. First, we display here that the improved model can reproduce typical SWDs of absence seizures. Moreover, we focus on the function of EIN by means of bifurcation analysis and find that EIN can induce transition behaviors under Hopf-type and fold limit cycle bifurcations. Specifically, the system has three stable solutions composing a tri-stable region. In this region, there are three attraction basins, which hints that external stimulation can drive the system trajectory from one basin to another, thereby eliminating abnormal oscillations. Furthermore, we compare the increasing ramp with rectangular pulse and optimize stimulation waveforms from the perspective of electrical charges input. The controlling role of the single increasing ramp to absence seizures is remarkable and the optimal stimulus parameters have been found theoretically. This work provides a computational model containing EIN and a theoretical basis for future physiological experiments and clinical research studies.


Assuntos
Epilepsia Tipo Ausência , Interneurônios , Córtex Cerebral , Estimulação Elétrica , Humanos , Interneurônios/fisiologia , Convulsões
12.
Tech Coloproctol ; 26(10): 775-781, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35962294

RESUMO

BACKGROUND: Most patients with perianal fistulizing Crohn's disease (pfCD) present with complex types of perianal fistulas and need repetitive repair operations, resulting in a high risk of sphincter injury. Fistula-tract Laser Closure (FiLaC™) is a novel sphincter-saving technique that obliterates the fistula tract with a photothermal effect. The aim of the present systematic review and meta-analysis was to evaluate the efficacy and safety of FiLaC in pfCD. METHODS: This study was conducted according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Electronic databases, including PubMed, Embase, Cochrane Library and Wanfang Data were searched for published articles from January 2000 to June 2021. The clinicaltrials.gov website was searched for completed or ongoing trials on pfCD and FiLaC™. The references of each article were also searched for eligible data. The main outcome was the primary healing rate of the FiLaC™ procedure. Additionally, fecal incontinence was analyzed as the secondary outcome to evaluate the safety of FiLaC™. RESULTS: Six studies met the eligibility criteria and were included in the final analysis. All studies were published within the past 6 years and came from European countries. There were 50 pfCD patients recruited, and 31 patients' fistulas were healed after FiLaC™. The pooled primary healing rate was 68% (95% CI 53.0-84.0%, I2 = 27%, p = 0.23). There was no major fecal incontinence after surgery. CONCLUSIONS: These data suggest that FiLaC™ may be an effective and safe procedure for pfCD patients. However, the evidence is poor and there is a need for more high-quality prospective controlled studies with long-term follow-up before this minimally invasive technique is recommended for surgical treatment of pfCD.


Assuntos
Doença de Crohn , Incontinência Fecal , Fístula Retal , Doença de Crohn/complicações , Incontinência Fecal/complicações , Humanos , Lasers , Estudos Prospectivos , Fístula Retal/complicações , Fístula Retal/cirurgia , Resultado do Tratamento
13.
Zhonghua Wai Ke Za Zhi ; 60(3): 268-272, 2022 Mar 01.
Artigo em Zh | MEDLINE | ID: mdl-35078302

RESUMO

Component malrotation is one of the major causes of failure in total knee arthroplasty.Based on previous researches,Insall line has excessive external rotation tendency.Although Akagi line is the most recognized anatomical axis at present,it still has a certain tendency of internal rotation.The tibial posterior condylar axis is not suitable for symmetrical component and yet the Curve-on-Curve technique is not suitable for anatomic component.In addition,reference to any fixed anatomical markers cannot ensure the rotation consistency of tibiofemoral component in extension position.Although range of motion technique is beneficial to tibiofemoral rotation synchronization,its clinical effect seems to be unstable.Nevertheless,Patients can obtain good postoperative results with all major techniques.Before the recognized "gold standard" is defined,orthopedic surgeons can determine the rotation alignment of tibial component according to their most accustomed surgical method.With a deeper understanding of knee anatomy,biomechanics and kinematics,digital assistive technology may be expected to become a breakthrough in the tibial rotational alignment.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Osteoartrite do Joelho , Artroplastia do Joelho/métodos , Fêmur/cirurgia , Humanos , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/cirurgia , Amplitude de Movimento Articular , Tíbia/cirurgia
14.
Phys Rev Lett ; 127(5): 055001, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34397224

RESUMO

Hot electrons generated by laser-plasma instabilities degrade the performance of laser-fusion implosions by preheating the DT fuel and reducing core compression. The hot-electron energy deposition in the DT fuel has been directly measured for the first time by comparing the hard x-ray signals between DT-layered and mass-equivalent ablator-only implosions. The electron energy deposition profile in the fuel is inferred through dedicated experiments using Cu-doped payloads of varying thickness. The measured preheat energy accurately explains the areal-density degradation observed in many OMEGA implosions. This technique can be used to assess the viability of the direct-drive approach to laser fusion with respect to the scaling of hot-electron preheat with laser energy.

15.
Phys Rev Lett ; 127(10): 105001, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34533333

RESUMO

Statistical modeling of experimental and simulation databases has enabled the development of an accurate predictive capability for deuterium-tritium layered cryogenic implosions at the OMEGA laser [V. Gopalaswamy et al.,Nature 565, 581 (2019)10.1038/s41586-019-0877-0]. In this letter, a physics-based statistical mapping framework is described and used to uncover the dependencies of the fusion yield. This model is used to identify and quantify the degradation mechanisms of the fusion yield in direct-drive implosions on OMEGA. The yield is found to be reduced by the ratio of laser beam to target radius, the asymmetry in inferred ion temperatures from the ℓ=1 mode, the time span over which tritium fuel has decayed, and parameters related to the implosion hydrodynamic stability. When adjusted for tritium decay and ℓ=1 mode, the highest yield in OMEGA cryogenic implosions is predicted to exceed 2×10^{14} fusion reactions.

16.
Philos Trans A Math Phys Eng Sci ; 379(2189): 20200011, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33280561

RESUMO

Laser-direct drive (LDD), along with laser indirect (X-ray) drive (LID) and magnetic drive with pulsed power, is one of the three viable inertial confinement fusion approaches to achieving fusion ignition and gain in the laboratory. The LDD programme is primarily being executed at both the Omega Laser Facility at the Laboratory for Laser Energetics and at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. LDD research at Omega includes cryogenic implosions, fundamental physics including material properties, hydrodynamics and laser-plasma interaction physics. LDD research on the NIF is focused on energy coupling and laser-plasma interactions physics at ignition-scale plasmas. Limited implosions on the NIF in the 'polar-drive' configuration, where the irradiation geometry is configured for LID, are also a feature of LDD research. The ability to conduct research over a large range of energy, power and scale size using both Omega and the NIF is a major positive aspect of LDD research that reduces the risk in scaling from OMEGA to megajoule-class lasers. The paper will summarize the present status of LDD research and plans for the future with the goal of ultimately achieving a burning plasma in the laboratory. This article is part of a discussion meeting issue 'Prospects for high gain inertial fusion energy (part 2)'.

17.
Zhonghua Yi Xue Za Zhi ; 101(2): 152-156, 2021 Jan 12.
Artigo em Zh | MEDLINE | ID: mdl-33455133

RESUMO

Objective: To discuss the value and technique of clip remodeling in microsurgical treatment of intracranial aneurysms via keyhole approaches. Methods: The clinical data of patients with intracranial aneurysms, who were treated by microsurgical clipping via keyhole approaches from January 2017 to December 2019, were retrospectively analyzed. The clips were remodeled based on the aneurysmal characteristics during the procedure in 27 cases. Angiography was obtained within one week after surgery in order to evaluate the position of clips and the security of lesions. All patients were followed up at the outpatient clinic to assess the clinical outcomes. Results: A total of 27 patients harbored 30 intracranial aneurysms, including 23 ruptured lesions and 7 unruptured ones. There were 9 middle cerebral artery aneurysms, 11 anterior communicating artery aneurysms, 9 posterior communicating artery aneurysms and 1 anterior cerebral artery aneurysm, respectively. Nine patients were operated via supraorbital keyhole approach, as well as 17 via pterional keyhole approach and one via hemispheric keyhole approach. Postoperative angiography revealed complete obliteration of lesions without residual filling in all cases. Twenty-five patients recovered well at discharge and two presented with mild disability. After 3-36 months of follow-up, no rebleeding and new-onset neurological deficits were noted. Conclusion: Clip remodeling technique is a simple and effective option, which can alleviate the limitation of manipulative freedom under keyhole approaches and improve the microsurgical effect of intracranial aneurysms.


Assuntos
Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/cirurgia , Microcirurgia , Procedimentos Neurocirúrgicos , Estudos Retrospectivos , Instrumentos Cirúrgicos , Resultado do Tratamento
18.
Zhonghua Yi Xue Za Zhi ; 101(8): 573-578, 2021 Mar 02.
Artigo em Zh | MEDLINE | ID: mdl-33663188

RESUMO

Objective: To explore the difference in the expression profile of circular RNA in peripheral blood mononuclear cells between patients with mild and severe influenza pneumonia. Methods: From December 2018 to March 2019, 10 inpatients with mild and 10 inpatients with severe influenza pneumonia admitted to the Department of Infection and Clinical Microbiology of Beijing Chaoyang Hospital were included. Clariom™ D gene chip was used to explore the circRNA expression profiles of peripheral blood mononuclear cells (PBMC) isolated from the patients. The absolute value of the fold change (FC value)>2 and P<0.05 were used as the criteria to screen the differentially expressed circRNA, and the gene ontology (GO) enrichment analysis and the Kyoto Encyclopedia of Gene and Genome database (Kyoto Encyclopedia of Genes and Genomes, KEGG) signal pathway enrichment analysis were also performed. Results: The age of mild patients [M (P25, P75)] was 62.0 (34.5, 69.8) years old, including 4 males; the age of severe patients [M (P25, P75)] was 50.0 (37.0, 60.0) years old, all were males. A total of 137 differentially expressed circRNAs in PBMCs of mild and severe patients were screened. The numbers of up-regulated and down-regulated circRNAs in mild patients were 101 and 36, respectively. Among them, hsa_circ_0091073 (FC value=160.898, P<0.05) was the most significantly up-regulated circRNA and hsa_circ_0092219 (FC value =-17.630, P<0.05) was the most significantly down-regulated circRNA. GO enrichment analysis showed that a total of 111 secondary GO items were significantly associated with related differential expression of circRNA (P<0.05). The GO terms associated with upregulated circRNAs included DNA-templated transcription, regulation of DNA-templated transcription, regulation of transcription from RNA polymerase Ⅱ promoter, etc.; The GO terms associated with downregulated circRNAs included neutrophil degranulation, killing of cells of other organism, defense response to fungus, etc. KEGG signaling pathway analysis showed that there were 37 metabolic pathways related to differentially expressed circRNAs (P<0.05). Signaling pathways related to up-regulated circRNAs included nuclear factor-κB (NF-κB) signaling pathway, mitogen-activated protein kinase (MAPK) signaling pathway, tumor necrosis factor (TNF) signaling pathway, etc. Signaling pathways related to down-regulation of circRNAs included cancer transcription disorders, folate carbon pool, and other types of O-glycan biosynthesis. Conclusion: The expression of circRNA in PBMC of mild and severe influenza pneumonia patients is significantly different, and it may play a role in the pathogenic mechanism of influenza pneumonia through multiple signal pathways.


Assuntos
Influenza Humana , Pneumonia , Idoso , Humanos , Influenza Humana/genética , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , RNA Circular
19.
Zhonghua Fu Chan Ke Za Zhi ; 56(8): 561-568, 2021 Aug 25.
Artigo em Zh | MEDLINE | ID: mdl-34420288

RESUMO

Objective: To analyze the clinical efficacy and pregnancy outcomes of gonadotropin-releasing hormone agonist (GnRH-a) based fertility-sparing re-treatment in women with endometrial carcinoma (EC) and atypical endometrial hyperplasia (AEH) who failed with oral progestin therapy. Methods: Forty cases with EC or AEH who failed to respond to oral progestin were included from January 2012 to December 2020 at Peking Union Medical College Hospital. Combination of GnRH-a with levonorgestrel-releasing intrauterine system (group GLI: a subcutaneous injection of GnRH-a every 4 weeks and LNG-IUS insertion constantly) or the combination of GnRH-a with aromatase inhibitor (group GAI: a subcutaneous injection of GnRH-a every 4 weeks and oral letrozole 2.5 mg, daily) were used for these patients. Histological evaluation were performed at the end of each course (every 3-4 months) by hysteroscopy and curettage. After the complete remission (CR), all patients were followed up regularly. Results: (1) Clinical characteristics:among the 40 patients with EC or AEH, the median age at diagnosis was 31 years (range: 22-40 years) and the median body mass index was 24.7 kg/m2 (range: 18.9-39.5 kg/m2). (2) Efficacy of fertility-sparing re-treatment: 37 (92%, 37/40) patients achieved CR, 6 (6/7) in AEH and 31 (94%, 31/33) in EC patients. The CR rate was 93% (26/28) and 11/12 in group GLI and GAI, respectively. The median time to CR was 5 months (range: 3-12 months). At the end of the first therapy course, the CR rates in AEH and EC were 5/7 and 42% (14/33), at the second course, the CR rates were 6/7 and 82% (27/33), respectively. (3) Recurrence: after 25 months of median follow-up duration (range: 10-75 months), 8 (22%, 8/37) women developed recurrence, 1/6 in AEH and 7 (23%, 7/31) in EC patients, with the median recurrence time of 18 months (range: 9-26 months). Among them, two cases who had completed childbirth chose to receive hysterectomy directly. Six patients met the criteria of fertility-preserving therapy and received conservative treatment again and 5 (5/6) of them achieved CR. (4) Pregnancy: of the 37 patients with CR, 33 desired to conceive. Ten women attempted to get pregnancy spontaneously and 23 cases with assisted reproductive technology. Fourteen (42%, 14/33) patients became pregnant, including 9 (27%, 9/33) live births, 3 (9%, 3/33) missed abortions, and 2 (6%, 2/33) miscarriages at the second trimester. Conclusions: GnRH-a based fertility-sparing re-treatment in AEH or EC patients who failed with oral progestin therapy achieved good treatment effect and reproductive outcomes. It is an encouraging alternative regime for patients who failed with oral progestin therapy.


Assuntos
Neoplasias do Endométrio , Preservação da Fertilidade , Neoplasias do Endométrio/tratamento farmacológico , Feminino , Hormônio Liberador de Gonadotropina , Humanos , Hiperplasia , Recidiva Local de Neoplasia/tratamento farmacológico , Gravidez , Progestinas
20.
Ann Chir Plast Esthet ; 66(6): 440-446, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33966905

RESUMO

BACKGROUND: Improving the survival rate of fat grafts is yet a difficult problem in the field of autologous fat transplantation. Prevailing methods such as making nanofat and SVF are time-consuming. Hence, the role of additives application in the improvement of fat graft survival during fat transplantation was considered and preliminarily evaluated in a rabbit animal model. METHODS: A rabbit animal model was established where rabbit ears were injected with a mixture of 1.5mL of adipose tissue and 1mL of saline (group A), 1.5mL of adipose tissue and 1mL of botulinum toxin A (BoNTA) (group B), 1.5mL of adipose tissue and 1mL of prostaglandin E2 (groupC), 1.5mL of adipose tissue and 1mL of PDRN (group D) respectively. Then, the extents of neovascularization and inflammation were evaluated on the 7th, 14th, 28th, 42nd, 56th and 70th day after injection by ELISA assays and H&E and immunofluorescence staining. RESULTS: The results showed that pre-treatment with BoNTA, prostaglandin E2 and PDRN improved graft volume and weight. The H&E and immunofluorescence staining revealed that BoNTA, prostaglandin E2 and PDRN improved the graft angiogenesis. Simultaneously, TNF-α expression level detected by ELISA was the lowest in the PDRN group. CONCLUSION: Henceforth, the present preliminary study suggests that pre-transplantation treatment with BoNTA, prostaglandin E2 and PDRN can improve the fat graft angiogenesis and graft integrity, whereby the effect of adding PDRN may be significant.


Assuntos
Tecido Adiposo , Sobrevivência de Enxerto , Animais , Modelos Animais de Doenças , Coelhos , Taxa de Sobrevida , Transplante Autólogo
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