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1.
Front Microbiol ; 14: 1244239, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37779725

RESUMO

Wolbachia have been developed as a tool for protecting humans from mosquito populations and mosquito-borne diseases. The success of using Wolbachia relies on the facts that Wolbachia are maternally transmitted and that Wolbachia-induced cytoplasmic incompatibility provides a selective advantage to infected over uninfected females, ensuring that Wolbachia rapidly spread through the target pest population. Most transinfected Wolbachia exhibit a strong antiviral response in novel hosts, thus making it an extremely efficient technique. Although Wolbachia has only been used to control mosquitoes so far, great progress has been made in developing Wolbachia-based approaches to protect plants from rice pests and their associated diseases. Here, we synthesize the current knowledge about the important phenotypic effects of Wolbachia used to control mosquito populations and the literature on the interactions between Wolbachia and rice pest planthoppers. Our aim is to link findings from Wolbachia-mediated mosquito control programs to possible applications in planthoppers.

3.
J Craniofac Surg ; 34(8): 2302-2307, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37427957

RESUMO

Computational fluid dynamics (CFD) was introduced into the study of palate growth and development to explain the mechanisms by which mouth breathing affects palate descent from an aerodynamic perspective. Cone beam computed tomography (CBCT) data were used to reconstruct a 3-dimensional model during natural mouth breathing of a volunteer. The model was imported into CFX 19.0 for numerical simulation of nasal breathing, mouth-nasal breathing, and mouth breathing. The pressure in the oronasal cavity was analyzed, and the pressure difference between the oral and nasal surfaces of hard palate under different breathing patterns was calculated. CFD can be used to simulate the stress on the oral and nasal surfaces of the palate under different breathing patterns. The pressure differences and resultant force between the oral and nasal surfaces of the hard palate during nasal inspiration, nasal expiration, mouth-nasal inspiration, mouth-nasal expiration, mouth inspiration, and mouth expiration were 0 Pa, 4 Pa (upward), 9 Pa (upward), 3 Pa (downward), 474 Pa (upward), 263 Pa (downward), respectively, and 87.99 N (upward), 88.03 N (upward), 88.01 N (upward), 88.01 N (upward), 88.05 N (upward), 87.94 N (upward), respectively. Therefore, CFD can be used to investigate the growth and development of the palate. When the volunteer opened his mouth, the pressure difference between the oral and nasal surfaces of the hard palate was about 88 N upward regardless of whether there was airflow in the mouth. The reversal of the direction of the force on the hard palate may be one of the factors affecting its descent of it.


Assuntos
Fissura Palatina , Respiração Bucal , Humanos , Hidrodinâmica , Respiração , Nariz , Palato Duro
4.
Orthop Surg ; 15(7): 1756-1762, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37232108

RESUMO

OBJECTIVE: When considering surgical treatment options, many patients who undergo hip arthroscopy value continuing active lifestyles. To address these concerns, the purpose of this study was to determine the effect of preoperative activity level on postoperative patient-reported outcomes (PROs) in femoroacetabular impingement syndrome (FAIS) patients following hip arthroscopy. METHODS: Data was retrospectively reviewed for FAIS patients who received hip arthroscopy between 2016 and 2018. Patients were divided into active group and inactive group based on preoperative HOS-SSS scores. Preoperative active patients were 1:1 propensity-score matched to inactive patients based on age, sex, BMI, and follow-up period. PROs (HOS-ADL, HOS-ADL, iHOT-12, mHHS), VAS scores, radiographic measures, performed procedures, complications, and revision surgery were compared and analyzed for both groups by Student's t test. RESULTS: A total of 71 patients in the active group and 71 patients in the inactive group were found using propensity-score matching. Active patients had superior preoperative HOS-ADL, HOS-SSS, iHOT-12, mHHS (p < 0.001 for all), and VAS (p = 0.002) scores compared with inactive patients. At the final follow-up, active patients still had better PROs in HOS-ADL (p = 0.003), HOS-SSS (p < 0.001), iHOT-12 (p = 0.043), and mHHS scores (p = 0.003). There was no difference detected in postoperative VAS score (p = 0.117) between the two groups. However, inactive patients showed significantly higher net improvement in HOS-ADL (p = 0.009), HOS-SSS (p = 0.005), and iHOT-12 (p = 0.023). CONCLUSIONS: Active patients have absolute higher preoperative PROs and achieve better postoperative PROs than inactive patients. However, inactive patients can obtain greater net improvements in PROs following hip arthroscopic surgery, with comparable pain alleviation as active patients.


Assuntos
Impacto Femoroacetabular , Humanos , Impacto Femoroacetabular/cirurgia , Articulação do Quadril/cirurgia , Artroscopia/métodos , Estudos Retrospectivos , Resultado do Tratamento , Atividades Cotidianas , Seguimentos
5.
Orthop Surg ; 15(1): 223-229, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36440529

RESUMO

OBJECTIVE: Global pincer is a relatively rare form of pincer deformity and is typically associated with technical challenges during surgery. So far, controversy remains whether patients with global pincer have equivalent surgical outcomes compared to patients with focal pincer. This study compares the clinical outcomes of arthroscopic treatment between patients with global pincer femoroacetabular impingement (FAI) and focal pincer FAI in the Chinese population. METHODS: Data were retrospectively collected from patients with global and focal pincer FAI who underwent hip arthroscopy with a minimum two-year follow-up between April 2016 and December 2018. Radiographic measurements, arthroscopic procedures, preoperative and postoperative patient-reported outcomes (PROs) including modified Harris hip score (mHHS), hip outcome score-activities of daily living (HOS-ADL), international hip outcome tool-12 (iHOT-12), and visual analogue scale (VAS) scores, rates of revision surgery and conversion to total hip arthroplasty (THA) were recorded. Achievement of minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) was compared for the VAS, mHHS, HOS-ADL, and iHOT-12 scores between groups. RESULTS: The total of 33 and 167 patients were included in the global and focal group, respectively. There were no intergroup differences in age, gender, body mass index or follow-up times. Lateral center-edge angle (LCEA) was reduced in both groups postoperatively. Both groups demonstrated significant improvements in PROs compared with preoperative levels at the final follow-up. The preoperative scores showed significant differences in terms of mHHS (60.34 vs 62.90, P = 0.031) and HOS-ADL (61.45 vs 64.74, P = 0.022) scores between two groups, and the improvement of HOS-ADL score was significantly higher in global group (P = 0.027). However, the postoperative scores, including VAS, mHHS, HOS-ADL, and iHOT-12 scores, showed no significant differences between two groups. And there were no significant differences in the rate of meeting the PASS and MCID between groups. One (3.0%) in the global group and six (3.6%) patients in the focal group underwent revision arthroscopy respectively, with no significant difference (P = 0.876). There were no conversions to THA in both groups. CONCLUSIONS: Arthroscopic management of global pincer FAI can achieve excellent functional scores at minimum 2-year follow-up. The outcomes were similar to focal pincer FAI patients with a low rate of secondary procedure.


Assuntos
Impacto Femoroacetabular , Humanos , Impacto Femoroacetabular/cirurgia , Estudos Retrospectivos , Articulação do Quadril/cirurgia , Seguimentos , Artroscopia , Atividades Cotidianas , Resultado do Tratamento
6.
Opt Express ; 30(23): 42057-42068, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366667

RESUMO

Photonics physically promises high-speed and low-consumption computing of matrix multiplication. Nevertheless, conventional approaches are challenging to achieve large throughput, high precision, low power consumption, and high density simultaneously in a single architecture, because the integration scale of conventional approaches is strongly limited by the insertion loss of cascaded optical phase shifters. Here, we present a parallel optical coherent dot-product (P-OCD) architecture, which deploys phase shifters in a fully parallel way. The insertion loss of phase shifters does not accumulate at large integration scale. The architecture decouples the integration scale and phase shifter insertion loss, making it possible to achieve superior throughput, precision, energy-efficiency, and compactness simultaneously in a single architecture. As the architecture is compatible with diverse integration technologies, high-performance computing can be realized with various off-the-shelf photonic phase shifters. Simulations show that compared with conventional architectures, the parallel architecture can achieve near 100× higher throughput and near 10× higher energy efficiency especially with lossy phase shifters. The parallel architecture is expected to perform its unique advantage in computing-intense applications including AI, communications, and autonomous driving.

7.
Biochem Biophys Res Commun ; 635: 77-83, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36257195

RESUMO

Articular cartilage defects remain the most common and challenging joint disease. Cartilage lacks the self-healing capacity after injury due to its avascularity. Recently, stem cell-based therapy has been applied for cartilage regeneration. However, the critical target for stem cells during chondrogenesis remains unclear. We first reported that LDL receptor-related protein 3 (LRP3) expression was markedly increased during chondrogenesis in stem cells. Furthermore, LRP3 was an effective chondrogenic stimulator, as confirmed by knockdown and overexpression experiments and RNA sequencing. In addition, inhibition of LRP3 suppressed proliferation and induced apoptosis. Therefore, our study first defined a new chondrogenic stimulator, LRP3, with detailed clarification, which provided a novel target for stem cell-based cartilage regeneration.


Assuntos
Cartilagem Articular , Células-Tronco Mesenquimais , Condrogênese/genética , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular , Células-Tronco , Cartilagem Articular/metabolismo , Apoptose , Proliferação de Células , Receptores de LDL/metabolismo
8.
Orthop J Sports Med ; 10(3): 23259671221083581, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35340730

RESUMO

Background: To better restore the anatomy of the native anterior cruciate ligament (ACL) attachment and fiber arrangement, researchers have developed techniques for changing the shape of the ACL bone tunnel during ACL reconstruction. Purpose: To compare the coverage of the ACL tibial footprint and influence on the anterior root of lateral meniscus (ARLM) between a rounded-rectangular tibial tunnel and a conventional round tibial tunnel for ACL reconstruction. Study Design: Controlled laboratory study. Methods: A total of 16 (8 matched-paired) fresh-frozen human cadaveric knees were distributed randomly into 2 groups: a rounded-rectangular tunnel (RRT) group and a round tunnel (RT) group. One of the knees from each pair was reamed with rounded-rectangular tibial tunnel, whereas the other was reamed with round tibial tunnel. Coverage of the ACL tibial footprint and areas of ARLM attachment before and after reaming were measured using 3-dimensional isotropic magnetic resonance imaging. Results: In the RRT group, the average percentage of ACL tibial footprint covered by the tunnel was 70.8% ± 2.5%, which was significantly higher than that in the RT group (48.2% ± 6.4%) (P = .012). As for the ARLM attachment area, in the RT group, there was a significant decrease (22.5% ± 5.9%) in ARLM attachment area after tibial tunnel reaming compared with the intact state (P < .001). Conversely, in the RRT group, the ARLM attachment area was not significantly affected by tibial tunnel reaming. Conclusion: Rounded-rectangular tibial tunnel was able to better cover the native ACL tibial footprint and significantly lower the risk of iatrogenic injury to the ARLM attachment than round tibial tunnel during ACL reconstruction.

9.
Arthroscopy ; 38(3): 850-859.e2, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34052387

RESUMO

PURPOSE: To investigate the kinematics differences between round-tunnel (ROT) and flat-tunnel (FLT) techniques in anterior cruciate ligament (ACL) reconstruction when using hamstring graft. METHODS: Nine matched pairs of fresh-frozen cadaveric knees were evaluated for the kinematics of intact, ACL-sectioned, and either ROT or FLT reconstructed knees. The graft bundles for FLT technique were separately tensioned. A 6 degrees of freedom robotic system was used to assess knee laxity: (1) 134-N anterior tibial load at 0°, 15°, 30°, 60°, and 90°of knee flexion; (2) 10 Nm of valgus torque followed by 5 Nm of internal rotation torque simulates a pivot-shift test at 15° and 30°; (3) 5-Nm internal and external rotation torques at 0°, 15°, 30°, 60°, and 90°; (4) 10-Nm varus and valgus torques at 15° and 30°. RESULTS: Significant differences were found for ROT versus FLT techniques in terms of the simulated pivot-shift test at 15° (2.5 mm vs 1.4 mm, respectively, difference from intact; P =.039) and the internal rotation test at 15° (2.5° vs 0.5°, respectively, difference from intact; P =.034) and 30° (2.0° vs 0.4°, respectively, difference from intact; P =.014). No significant differences were found between groups during 134-N anterior tibial load, external rotation and valgus/varus rotation. Neither technique was able to reproduce the intact state during an anterior tibial load and simulated pivot-shift test. CONCLUSIONS: The FLT technique with independently tensioned bundles shows the same anterior control as the ROT technique but better restores rotational stability in terms of the simulated pivot-shift test and the internal rotation test in anatomic ACL reconstruction at time zero. CLINICAL RELEVANCE: The FLT technique with independently tensioned bundles of ACL reconstruction appears to be a viable, more anatomic technique than the ROT technique in mimicking flat anatomy and rotational stability of native ACL.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Instabilidade Articular , Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Fenômenos Biomecânicos , Cadáver , Humanos , Instabilidade Articular/cirurgia , Articulação do Joelho/cirurgia , Amplitude de Movimento Articular
12.
Ying Yong Sheng Tai Xue Bao ; 31(4): 1378-1388, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32530214

RESUMO

Non-structural carbohydrates (NSC) are essential substances for the tree growth and metabolism, and play an important role in environmental adaptation of trees. At temporal scale, NSC contents in trees have limited inter-annual variation, which could be attributed to the strategy of tree growth and carbon storage. Different factors influence NSC contents of trees in various climatic regions, which change substantially at the seasonal scale. At spatial scale, the variations of NSC content in trees show an insignificantly decreasing trend with the decreases of latitude at global and continental scales, which are mainly related to the hydrothermal gradients. The trend at regional scale is opposite because of the decrease of hydrothermal gradients and lower sample frequency. More sophisticated relations exist between the variations of NSC content in trees and altitudes, which are caused by species-specific characteristics and the variations of micro-habitat conditions. The variations of NSC content in trees at multiple spatial-temporal scales are generally determined by both biotic and abiotic factors, which are mainly dependent on the tradeoff among photosynthate production, respiratory depletion, and tree growth. Furthermore, the methods used for the determination of NSC content are different, which results in great uncertainties in comparing conclusions from different studies. The methods used for sample collection and measurement of NSC should be improved and unified to enhance the comparison among different studies. The NSC contents of trees in different age classes should be measured with all organs collected at multiple spatial-temporal scales. The underlying mechanisms, significance of NSC storage, transformation and allocation on tree growth and survival should be further discussed.


Assuntos
Metabolismo dos Carboidratos , Árvores , Carboidratos , Carbono , Estações do Ano
13.
Adv Mater ; 31(19): e1900597, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30924972

RESUMO

Graphene has a great potential to replace silicon in prospective semiconductor industries due to its outstanding electronic and transport properties; nonetheless, its lack of energy bandgap is a substantial limitation for practical applications. To date, straining graphene to break its lattice symmetry is perhaps the most efficient approach toward realizing bandgap tunability in graphene. However, due to the weak lattice deformation induced by uniaxial or in-plane shear strain, most strained graphene studies have yielded bandgaps <1 eV. In this work, a modulated inhomogeneous local asymmetric elastic-plastic straining is reported that utilizes GPa-level laser shocking at a high strain rate (dε/dt) ≈ 106 -107 s-1 , with excellent formability, inducing tunable bandgaps in graphene of up to 2.1 eV, as determined by scanning tunneling spectroscopy. High-resolution imaging and Raman spectroscopy reveal strain-induced modifications to the atomic and electronic structure in graphene and first-principles simulations predict the measured bandgap openings. Laser shock modulation of semimetallic graphene to a semiconducting material with controllable bandgap has the potential to benefit the electronic and optoelectronic industries.

14.
Sci Rep ; 4: 6612, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25327155

RESUMO

Synthesis of diamond, a multi-functional material, has been a challenge due to very high activation energy for transforming graphite to diamond, and therefore, has been hindering it from being potentially exploited for novel applications. In this study, we explore a new approach, namely confined pulse laser deposition (CPLD), in which nanosecond laser ablation of graphite within a confinement layer simultaneously activates plasma and effectively confine it to create a favorable condition for nanodiamond formation from graphite. It is noteworthy that due to the local high dense confined plasma created by transparent confinement layer, nanodiamond has been formed at laser intensity as low as 3.7 GW/cm(2), which corresponds to pressure of 4.4 GPa, much lower than the pressure needed to transform graphite to diamond traditionally. By manipulating the laser conditions, semi-transparent carbon films with good conductivity (several kΩ/Sq) were also obtained by this method. This technique provides a new channel, from confined plasma to solid, to deposit materials that normally need high temperature and high pressure. This technique has several important advantages to allow scalable processing, such as high speed, direct writing without catalyst, selective and flexible processing, low cost without expensive pico/femtosecond laser systems, high temperature/vacuum chambers.

15.
Nanoscale ; 6(11): 5853-8, 2014 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-24752401

RESUMO

Laser-induced photo-chemical synthesis of SnO2 nanotubes has been demonstrated by employing a nanoporous polycarbonate membrane as a template. The SnO2 nanotube diameter can be controlled by the nanoporous template while the nanotube length can be tuned by laser parameters and reaction duration. The microstructure characterization of the nanotubes indicates that they consist of mesoporous structures with sub 5 nm size nanocrystals connected by the twinning structure. The application of SnO2 nanotubes as an anode material in lithium ion batteries has also been explored, and they exhibited high capacity and excellent cyclic stability. The laser based emerging technique for scalable production of crystalline metal oxide nanotubes in a matter of seconds is remarkable. The compliance of the laser based technique with the existing technologies would lead to mass production of novel nanomaterials that would be suitable for several emerging applications.

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