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1.
Arch Microbiol ; 204(7): 381, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35687177

RESUMO

Based on morphological and phylogenetic analyses, an ectomycorrhizal fungus collected from Jiangxi, China, is described as a new species. R. atrofuscus is morphological characterized by a dark gray to black pileus, white to pale yellowish white hymenophore, a grayish brown to pale yellow context, which turning orange-yellow to rusty yellow when injured, a prominently and coarsely white to pale yellow to black reticulation on upper 3/4 or entire stipe, grayish yellow to pale yellow to yellowish brown basidiospores in KOH with measuring (7-)7.5-13(-13.5) × (3-)3.5-5(-5.5) µm. Phylogenetic analysis results showed that R. atrofuscus formed an independent lineage within Retiboletus. Descriptions and hand drawings of the new species and comparisons with similar species are presented.


Assuntos
Basidiomycota , Basidiomycota/genética , China , DNA Fúngico/genética , Filogenia , Análise de Sequência de DNA
2.
J Assist Reprod Genet ; 39(9): 2019-2026, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35925537

RESUMO

PURPOSE: To compare ovarian response and the number of transferable embryos between women with balanced autosomal translocations and women whose partners carry the translocation (control group). To investigate the predictive value of metaphase II (MII) oocyte number and biopsied embryo number for gaining at lowest one transferable embryo. DESIGN: We retrospectively analyzed 1942 preimplantation genetic testing for structural rearrangements (PGT-SR) cycles of 1505 balanced autosomal translocation couples over 8 years. All cycles were divided into two subgroups: Robertsonian and reciprocal translocations (ROBT and ReBT). Receiver operator characteristic (ROC) curves were plotted to ascertain a cutoff of MII oocytes and biopsied embryos as predictors of gaining at lowest one transferable embryo. RESULT: There were no statistical differences in baseline features or ovarian response indicators regarding the number of retrieved/MII oocytes, E2 level on the day of HCG, and ovarian sensitivity index (OSI) between women with balanced autosomal translocations and control group (P > 0.05). A decreased number of transferable embryos were found in women with balanced autosomal translocations regardless of the type of translocation. The cutoff values for gaining at lowest one transferable embryo are 12.5 MII oocytes and 4.5 biopsied embryos, respectively. CONCLUSION: Women with balanced autosomal translocations have a normal ovarian response, but fewer transferable embryos, meaning that higher gonadotropin (Gn) doses may be required to increase transferable embryos. When fewer than 12.5 MII oocytes or 4.5 blastocysts are obtained in a PGT-SR cycle, couples should be notified that the likelihood of gaining a transferable embryo is low.


Assuntos
Transtornos Cromossômicos , Diagnóstico Pré-Implantação , Transtornos Cromossômicos/genética , Transferência Embrionária , Feminino , Fertilização in vitro , Testes Genéticos , Humanos , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Translocação Genética/genética
3.
World J Surg Oncol ; 19(1): 91, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33781288

RESUMO

BACKGROUND: Lymph node metastasis is a major prognostic sign of colorectal carcinoma and an important indicator for individualized treatment. M2 macrophages play a key role in carcinogenesis and tumor development by enhancing invasiveness and promoting lymph node metastasis. The purpose of this study was to investigate the effect of CD163-positive M2 macrophages on lymph node metastasis in colorectal carcinoma. METHODS: Postoperative lymph node tissues were obtained from 120 patients with colorectal carcinoma who underwent radical surgery in the First Affiliated Hospital of Jinzhou Medical University between December 2019 and May 2020. We detected the expression of the CD163 protein in lymph nodes using immunohistochemistry. Furthermore, the relationships between M2 macrophages identified by expression of CD163 and lymph node metastasis were analyzed using the independent sample t-test and Chi-square test. RESULTS: M2 macrophages were increased in metastatic lymph nodes and non-metastatic lymph nodes adjacent to the cancer. The M2 macrophage count was higher in patients with macro-metastases than in patients with micro-metastases. CONCLUSIONS: The presence of M2 macrophages represents an important indicator for lymph node metastasis in colorectal carcinoma and may be a potential marker for its prediction. Thus, M2 macrophage localization might offer a new target for the comprehensive treatment of colorectal carcinoma.


Assuntos
Neoplasias Colorretais , Humanos , Linfonodos/cirurgia , Metástase Linfática , Macrófagos , Prognóstico
4.
J Environ Manage ; 295: 113048, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34147992

RESUMO

The Action Plan for Water Pollution Prevention and Control (i.e., the "10-Point Water Plan") is a regulation formulated by China to prevent and control water pollution and ensure China's water safety. To test the policy effect of the "10-Point Water Plan", we use data from 269 cities for the period from 2012 to 2017 to examine whether the implementation of the plan can help reduce the intensity of industrial water pollution. The results show that the industrial water pollution intensity in Central and Western China is significantly higher than that in other regions, and the implementation of the "10-Point Water Plan" significantly reduces industrial water pollution intensity in China. We further find that upgrading industrial structures and technological innovation are effective ways to ameliorate the intensity of industrial water pollution. In terms of spatial heterogeneity, the impact of the "10-Point Water Plan" on reducing industrial water pollution is smaller in areas with high environmental regulation intensity than in areas with low environmental regulation intensity. We also find a strong inhibitory effect of environmental regulations on industrial water pollution intensity in areas with low environmental regulation intensity. Our findings support the positive policy effect of the "10-Point Water Plan" and provide significant policy implications for water pollution prevention and control actions in China and other countries.


Assuntos
Indústrias , Água , China , Cidades , Poluição Ambiental , Poluição da Água/prevenção & controle
5.
Zhonghua Nan Ke Xue ; 27(11): 1001-1005, 2021 Nov.
Artigo em Zh | MEDLINE | ID: mdl-37422872

RESUMO

Objective: To investigate the relationship between the level of the stress biomarker salivary alpha amylase (SAA) and semen quality in infertile young men. METHODS: Totally, 313 infertile and 96 normal healthy men, aged 20-40 years old, were enrolled in this study. The SAA levels and semen parameters of the subjects were measured and compared between the two groups. RESULTS: Compared with the normal healthy controls, the young infertility patients showed a significantly higher SAA level (ï¼»141.04 ± 44.13ï¼½ vs ï¼»151.48 ± 38.42ï¼½ µmol/L, P < 0.05) and percentage of immotile sperm (IMS) (ï¼»39.98 ± 14.53ï¼½% vs ï¼»64.48 ± 26.32ï¼½%, P < 0.05), but lower sperm concentration (ï¼»44.23 ± 21.63ï¼½ vs ï¼»32.42 ± 23.07ï¼½ ×106/ml, P < 0.05) and percentage of progressively motile sperm (PMS) (ï¼»52.13 ± 15.42ï¼½% vs ï¼»27.91 ± 21.22ï¼½%, P < 0.05). Sperm concentration (ï¼»26.33 ± 31.83ï¼½ vs ï¼»35.28 ± 27.70ï¼½ ×106/ml, P < 0.05) and the percentage of PMS were remarkably lower in the infertile men with a high than in those with a low SAA level (ï¼»19.85 ± 21.55ï¼½% vs ï¼»31.70 ± 20.02ï¼½%, P < 0.05), while the percentage of IMS was higher in the former than in the latter group (ï¼»74.19 ± 26.84ï¼½% vs ï¼»59.92 ± 24.85ï¼½%, P < 0.05). The SAA level in the young infertility patients was correlated positively with the percentage of IMS (r = 0.170, P < 0.01), but negatively with sperm concentration (r = -0.227, P < 0.01) and the percentage of PMS (r = -0.468, P < 0.01). CONCLUSIONS: The stress biomarker salivary alpha amylase level in infertile young men is negatively correlated with semen quality, and therefore semen parameters can be improved by reducing the stress level.

6.
Angew Chem Int Ed Engl ; 60(28): 15225-15229, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33855792

RESUMO

Inhaled gene therapy poses a unique potential of curing chronic lung diseases, which are currently managed primarily by symptomatic treatments. However, it has been challenging to achieve therapeutically relevant gene transfer efficacy in the lung due to the presence of numerous biological delivery barriers. Here, we introduce a simple approach that overcomes both extracellular and cellular barriers to enhance gene transfer efficacy in the lung in vivo. We endowed tetra(piperazino)fullerene epoxide (TPFE)-based nanoparticles with non-adhesive surface polyethylene glycol (PEG) coatings, thereby enabling the nanoparticles to cross the airway mucus gel layer and avoid phagocytic uptake by alveolar macrophages. In parallel, we utilized a hypotonic vehicle to facilitate endocytic uptake of the PEGylated nanoparticles by lung parenchymal cells via the osmotically driven regulatory volume decrease (RVD) mechanism. We demonstrate that this two-pronged delivery strategy provides safe, wide-spread and high-level transgene expression in the lungs of both healthy mice and mice with chronic lung diseases characterized by reinforced delivery barriers.


Assuntos
Compostos de Epóxi/química , Fulerenos/química , Técnicas de Transferência de Genes , Pneumopatias/terapia , Nanopartículas/química , Doença Crônica , Humanos , Pneumopatias/metabolismo
7.
Appl Opt ; 59(8): 2393-2399, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32225773

RESUMO

The geometrical phase analysis (GPA) method, which is an efficient and powerful noncontact method to obtain the strain field, has already been widely applied in deformation measurement in micro- and nano-scale. It is easy to get the strain field accurately; however, the displacement field is unreliable in some cases. Therefore, a subpixel displacement match method hereby is applied in the GPA method for the first time, to the best of our knowledge, to overcome this defect. The presented algorithm's limit error of 0.01 pixel under ideal conditions can match two corresponding local areas in reference and deformation image, and, thus, the displacement with subpixel precision of this point can be established. Owing to the continuity of the displacement field, the displacements of other points can be obtained subsequently. The error that is associated with the existing method will be dealt with in detail and verified by simulation further. Combined with simulation, the performance of the presented method is demonstrated; furthermore, the noise introduced by the imaging system is taken into consideration. Finally, a typical bending test was performed, and the result agrees well with the theoretical analysis. Both the simulation and experiment results prove that the presented method is effective and robust.

8.
J Environ Manage ; 270: 110806, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32507737

RESUMO

Soil pollution is a serious environmental issue in China. As a key subject of agricultural practices, promoting Chinese farmers' Pro-Environmental Behavior (PEB) through increasing their soil pollution risk perception is an important means for soil protection, agricultural transformation and ecological development. In this study, we distinguish four dimensions of soil pollution risk perception: fact perception (FP), loss perception (LP), cause perception (CP) and response behavior ability perception (RBAP). We conceptualize a model that depicts the relationships between the four dimensions of Chinese farmers' soil pollution risk perception and their PEB and the moderating effect of farms' household income level on these relationships. Using a questionnaire survey to collect empirical data, we find: first, the four dimensions of Chinese farmers' soil pollution risk perception have positive effects on their PEB; second, Chinese farmers' household income level positively moderates the relationships between their FP, LP and CP and their PEB but its moderating effect on the relationship between their RBAP and their PEB is not significant. Relevant theory and policy implications for environmental management are discussed in the paper.


Assuntos
Agricultura , Fazendeiros , China , Poluição Ambiental , Fazendas , Humanos
9.
Reproduction ; 156(1): 81-92, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29752296

RESUMO

The quality of postovulatory metaphase II oocytes undergoes a time-dependent deterioration as a result of the aging process. Melatonin is considered to be an anti-aging agent. However, the underlying mechanisms of how melatonin improves the quality of postovulatory aged oocytes remain largely unclear. In this study, by using mouse model, we found that there were elevated reactive oxygen species levels and impaired mitochondrial function demonstrated by reduced mitochondrial membrane potential and increased mitochondrial aggregation in oocytes aged 24 h, accompanied by an increased number of meiotic errors, unregulated autophagy-related proteins and early apoptosis, which led to decreased oocyte quality and disrupted developmental competence. However, all of these events can be largely prevented by supplementing the oocyte culture medium with 10-3 M melatonin. Additionally, we found that the expression of sirtuin family members (SIRT1, 2 and 3) was dramatically reduced in aged oocytes. In addition, in vitro supplementation with melatonin significantly upregulated the expression of SIRT1 and antioxidant enzyme MnSOD, but this action was not observed for SIRT2 and SIRT3. Furthermore, the protective effect of melatonin on the delay of oocyte aging vanished when the SIRT1 inhibitor EX527 was used to simultaneously treat the oocytes with melatonin. Consistent with this finding, we found that the postovulatory oocyte aging process was markedly attenuated when the oocytes were treated with the SIRT1 activator SRT1720. In conclusion, our data strongly indicate that melatonin delays postovulatory mouse oocyte aging via a SIRT1-MnSOD-dependent pathway, which may provide a molecular mechanism support for the further application of melatonin in the assisted reproductive technology field.


Assuntos
Melatonina/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sirtuína 1/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Células Cultivadas , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Oócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/genética , Superóxido Dismutase/metabolismo
10.
Biochem Biophys Res Commun ; 487(2): 313-319, 2017 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-28412368

RESUMO

Heat shock protein 90 (HSP90) is a molecular chaperone required for maintaining the stability and function of signal proteins that plays an important role in promoting the growth and survival of cancer cells. The incidence of papillary thyroid carcinoma (PTC) has been increasing in recent years. The effect of the novel non-geldanamycin HSP90 inhibitor NVP-AUY922 on apoptosis of papillary thyroid carcinoma cells has not been investigated. The influence of AUY922 on the survival of PTC cell lines K1 and IHH4 was evaluated. Cell viability was determined by cell counting kit method. Cell apoptosis was assessed by flow cytometry and western blotting and the potential mechanism was evaluated by western blotting and immunoprecipitation. Overexpression plasmid was transfected by Lipofectamine 2000 method. In K1 and IHH4 cell lines, after the treatment of AUY922, cell viability decreased, and the proportion of apoptosis cells increased. AUY922 caused the cleavage of PARP and caspase-3 proteins, and altered expression of survivin, which was a client protein of HSP90. In AUY922-treated cells, overexpression of survivin attenuated growth inhibition and cell apoptosis. The results indicate that AUY922 induces apoptotic cell death in PTC cells. Moreover, our findings demonstrate that AUY922 induced apoptosis by downregulating the expression of survivin protein in PTC cells.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma/tratamento farmacológico , Carcinoma/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas Inibidoras de Apoptose/metabolismo , Isoxazóis/administração & dosagem , Resorcinóis/administração & dosagem , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/metabolismo , Antineoplásicos/administração & dosagem , Carcinoma/patologia , Carcinoma Papilar , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Transdução de Sinais/efeitos dos fármacos , Survivina , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/patologia
11.
Clin Endocrinol (Oxf) ; 87(5): 572-580, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28585717

RESUMO

BACKGROUND: The rate of recurrent laryngeal nerve (RLN) palsy, a common complication of thyroid surgery, is especially high in thyroid reoperations. The present meta-analysis assesses whether intraoperative neuromonitoring (IONM) reduces the prevalence of RLN palsy in thyroid reoperations. DESIGN AND METHODS: A systematic literature search was conducted in the PubMed, SCIE and Wan Fang databases for studies published up to 31 August 2016. All data were analysed using STATA (version 11) software. Publication bias was assessed using Begg's funnel plot and Egger's test, and sensitivity analysis was performed. RESULTS: Nine studies including 2436 at-risk nerves met the inclusion criteria. The results were presented as pooled relative risks (RRs) with 95% confidence intervals (CI). The overall RLN palsy rate was significantly lower in reoperations conducted with IONM than in those conducted without IONM (RR=0.434, 95% CI=0.206-0.916, P=.029). High heterogeneity was found (I2 =70.2%, P=.001). The rates of transient RLN palsy with and without IONM did not differ significantly (RR=0.607, 95% CI=0.270-1.366, P=.227). The heterogeneity was high (I2 =67.4%, P=.005). However, IONM was significantly associated with a reduction in permanent RLN palsy (RR=0.426, 95% CI=0.196-0.925, P=.031). No significant heterogeneity was found (I2 =13.7%, P=.325). Funnel plots for overall and transient RLN palsy showed a possible publication bias. CONCLUSIONS: Intraoperative neuromonitoring (IONM) is associated with a reduction in overall and permanent RLN palsy in thyroid reoperations. However, given the limited sample size and heterogeneity in this meta-analysis, further studies are required to confirm our preliminary findings.


Assuntos
Monitorização Intraoperatória/métodos , Glândula Tireoide/cirurgia , Paralisia das Pregas Vocais/cirurgia , Humanos , Reoperação
12.
Acta Radiol ; 58(6): 719-725, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27856802

RESUMO

Background Cobey and Buck described methods to evaluate hindfoot alignment, but it is still unclear which method is better and easier to perform in clinical practice. Purpose To evaluate the optimal method for radiography of hindfoot alignment. Material and Methods We randomly selected 50 patients visiting the foot and ankle surgery outpatient department who underwent hindfoot alignment radiography between 1 July and 31 August 2015. Radiographs were taken using both Cobey's and Buck's methods. The patients were divided into three groups by calcaneal inclination angle. We assessed the calcaneotibial angle, calcaneovertical angle, and the distance from the bottom of the calcaneus to the mid-tibial axis. A comparative analysis was performed separately using the t-test. Results One hundred pairs of data for Cobey's and Buck's methods were obtained. The angles were analyzed separately in valgus, normal, and varus situations. The results showed no significant difference between Cobey's method and Buck's method regardless of any situation ( P > 0.05). Regarding the distance between the bottom of the calcaneus and the mid-tibial axis, the average result of Buck's method was about 1 mm larger than that of Cobey's method in the valgus and normal cases ( P < 0.05), except for varus cases ( P > 0.05). Conclusion Cobey's and Buck's techniques are the classic and popular hindfoot alignment assessment methods. The use of Buck's technique resulted in a better image with a less technical procedure and less time requirement. It is worthy of being popularized and used routinely for hindfoot radiography.


Assuntos
Mau Alinhamento Ósseo/diagnóstico por imagem , Calcâneo/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia/métodos , Radiografia/normas , Adulto Jovem
13.
BMC Musculoskelet Disord ; 18(1): 23, 2017 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-28103870

RESUMO

BACKGROUND: Osteochondral lesions of the talus (OLTs) are amongst the most common foot and ankle disorders. Varus ankle malalignment causes stress concentration on medial side of the joint, resulting in OLTs and osteoarthritis. For large symptomatic OLTs (>10 mm), Osteochondral autograft transplantation is usually recommended. This article highlights biplanar distal tibial osteotomy as an approach and management for patients with concomitant large OLTs and varus ankle malalignment. METHODS: From January 2012 to July 2014, 13 patients (6 male and 7 female) underwent surgery in our faculty and their average age was 55.4 (ranging from 34 to 69) years old. Oblique medial malleolar osteotomy was performed to expose the talar lesion, followed by an osteochondral autograft transplantation and distal tibial opening-wedge osteotomy. Weight-bearing X-rays were conducted and used for the measurement of radiographic parameters such as the tibial articular surface (TAS) and tibial lateral surface (TLS) angles. Ankle function of the subjects was evaluated according to the American Orthopaedic Foot and Ankle Society-Ankle and Hindfoot score (AOFAS-AH) questionnaires and Visual Analog Scale (VAS). RESULTS: 11 patients completed the follow-up over a mean period of 21.2 months. The average area of talar lesion was 135.9 mm2 while the average depth was 11.4 mm. The mean time for osseous union was 8.5 weeks. Donor site morbidity was not recorded in any of the cases. The mean AOFAS-AH and VAS improved from 53 to 90 points (p < 0.05) and 6.7 to 1.9 points (p < 0.05) respectively. The mean TAS angle improved from 83.1 to 90.3° (p < 0.05). CONCLUSIONS: Biplanar distal tibial osteotomy with the combination of osteochondral autograft transplantation could be used to address patients with concomitant large OLTs and varus ankle malalignment as this technique provides excellent visualization of the talar defect, favorable biomechanical environment for the ankle joint with high rate of good and excellent results.


Assuntos
Articulação do Tornozelo/cirurgia , Pé Torto Equinovaro/cirurgia , Osteocondrite/cirurgia , Osteotomia/métodos , Tálus/cirurgia , Tíbia/cirurgia , Adulto , Traumatismos do Tornozelo/complicações , Articulação do Tornozelo/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Transplante Autólogo , Suporte de Carga , Adulto Jovem
14.
Sensors (Basel) ; 17(4)2017 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-28375189

RESUMO

Harmonic force and torque, which are caused by rotor imbalance and sensor runout, are the dominant disturbances in active magnetic bearing (AMB) systems. To eliminate the harmonic force and torque, a novel control method based on repetitive control and notch filters is proposed. Firstly, the dynamics of a four radial degrees of freedom AMB system is described, and the AMB model can be described in terms of the translational and rotational motions, respectively. Next, a closed-loop generalized notch filter is utilized to identify the synchronous displacement resulting from the rotor imbalance, and a feed-forward compensation of the synchronous force and torque related to the AMB displacement stiffness is formulated by using the identified synchronous displacement. Then, a plug-in repetitive controller is designed to track the synchronous feed-forward compensation adaptively and to suppress the harmonic vibrations due to the sensor runout. Finally, the proposed control method is verified by simulations and experiments. The control algorithm is insensitive to the parameter variations of the power amplifiers and can precisely suppress the harmonic force and torque. Its practicality stems from its low computational load.

15.
Sensors (Basel) ; 16(9)2016 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-27657089

RESUMO

This paper describes a small range six-axis accelerometer (the measurement range of the sensor is ±g) with high sensitivity DCB (Double Cantilever Beam) elastic element. This sensor is developed based on a parallel mechanism because of the reliability. The accuracy of sensors is affected by its sensitivity characteristics. To improve the sensitivity, a DCB structure is applied as the elastic element. Through dynamic analysis, the dynamic model of the accelerometer is established using the Lagrange equation, and the mass matrix and stiffness matrix are obtained by a partial derivative calculation and a conservative congruence transformation, respectively. By simplifying the structure of the accelerometer, a model of the free vibration is achieved, and the parameters of the sensor are designed based on the model. Through stiffness analysis of the DCB structure, the deflection curve of the beam is calculated. Compared with the result obtained using a finite element analysis simulation in ANSYS Workbench, the coincidence rate of the maximum deflection is 89.0% along the x-axis, 88.3% along the y-axis and 87.5% along the z-axis. Through strain analysis of the DCB elastic element, the sensitivity of the beam is obtained. According to the experimental result, the accuracy of the theoretical analysis is found to be 90.4% along the x-axis, 74.9% along the y-axis and 78.9% along the z-axis. The measurement errors of linear accelerations ax, ay and az in the experiments are 2.6%, 0.6% and 1.31%, respectively. The experiments prove that accelerometer with DCB elastic element performs great sensitive and precision characteristics.

16.
Reprod Biomed Online ; 31(1): 44-50, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25982091

RESUMO

The ends of eukaryotic chromosomes contain specialized chromatin structures called telomeres, the length of which plays a key role in early human embryonic development. Although the effect of sperm preparation techniques on major sperm characteristics, such as concentration, motility and morphology have been previously documented, the possible status of telomere length and its relation with sperm preparation techniques is not well-known for humans. The aim of this study was to investigate the role of density gradient centrifugation in the selection of spermatozoa with longer telomeres for use in assisted reproduction techniques in 105 samples before and after sperm processing. After density gradient centrifugation, the average telomere length of the sperm was significantly longer (6.51 ± 2.54 versus 5.16 ± 2.29, P < 0.01), the average motile sperm rate was significantly higher (77.9 ± 11.8 versus 44.6 ± 11.2, P < 0.01), but average DNA fragmentation rate was significantly lower (11.1 ± 5.9 versus 25.9 ± 12.9, P < 0.01) compared with raw semen. Additionally, telomere length was positively correlated with semen sperm count (rs = 0.58; P < 0.01). In conclusion, density gradient centrifugation is a useful technique for selection of sperm with longer telomeres.


Assuntos
Centrifugação com Gradiente de Concentração , Técnicas de Reprodução Assistida , Análise do Sêmen , Espermatozoides/fisiologia , Telômero/genética , Separação Celular/métodos , Humanos , Masculino , Manejo de Espécimes/métodos
17.
Sensors (Basel) ; 15(7): 15661-83, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-26147726

RESUMO

In this paper, a new algorithm to improve the accuracy of estimating diameter at breast height (DBH) for tree trunks in forest areas is proposed. First, the information is collected by a two-dimensional terrestrial laser scanner (2DTLS), which emits laser pulses to generate a point cloud. After extraction and filtration, the laser point clusters of the trunks are obtained, which are optimized by an arithmetic means method. Then, an algebraic circle fitting algorithm in polar form is non-linearly optimized by the Levenberg-Marquardt method to form a new hybrid algorithm, which is used to acquire the diameters and positions of the trees. Compared with previous works, this proposed method improves the accuracy of diameter estimation of trees significantly and effectively reduces the calculation time. Moreover, the experimental results indicate that this method is stable and suitable for the most challenging conditions, which has practical significance in improving the operating efficiency of forest harvester and reducing the risk of causing accidents.

18.
J Magn Reson ; 358: 107612, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38118321

RESUMO

Floating cable traps (FCTs) enhance coil tuning, improve the signal-to-noise ratio of magnetic resonance imaging (MRI), and reduce the risks to patients. As MRI technology continues to advance, it becomes crucial to design efficient FCTs that are tailored to different magnetic fields and nuclei. Here, a method is proposed for determining and correcting the appropriate capacitances for FCTs in MRI systems. To validate the effectiveness of this approach, FCTs were designed and manufactured for hydrogen nuclei in magnetic fields of 1.5-14 T. The results of bench testing show that the attenuation of common-mode currents was more than -20 dB, and the maximum frequency deviation in all the FCTs was 0.345%. Furthermore, the results of magnetic resonance spin-echo imaging show that the signal-to-noise ratio was improved significantly by using the FCTs. Overall, this study shows the effectiveness of the designed FCTs in improving signal-to-noise ratio, and it provides valuable insights for designing efficient FCTs tailored to different magnetic fields and nuclei in MRI applications.

19.
Sci Rep ; 14(1): 4342, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38383583

RESUMO

Surgical intervention is typically recommended for thoracic ossification of the ligamentum flavum (TOLF). This study aimed to evaluate the efficacy and safety of a novel non-coaxial one-hole split endoscope (OSE) technique for treating TOLF. We performed OSE procedure on 13 patients with TOLF from June 2022 to July 2023. The mean operative time was 117.5 ± 15.4 min. VAS scores for lower limbs decreased from 6.5 ± 0.8 preoperative to 1.6 ± 0.4 at the last follow-up (P < 0.001). ODI scores improved from 62.4 ± 5.7 preoperative to 18.6 ± 2.2 at the last follow-up (P < 0.001), and mJOA scores increased from 5.1 ± 1.6 preoperative to 8.4 ± 1.5 at the latest follow-up (P < 0.001). All patients achieved ASIA scale grade D or E at the final follow-up, except for two patients remained residual limb numbness. None of the thirteen patients suffered from severe perioperative complications. The OSE technique proves to be a safe and effective procedure for treating TOLF or even with dura mater ossification, characterized by minimal surgical trauma, relatively smooth learning curve and flexible operation.


Assuntos
Ligamento Amarelo , Ossificação Heterotópica , Humanos , Osteogênese , Ossificação Heterotópica/cirurgia , Ossificação Heterotópica/complicações , Ligamento Amarelo/cirurgia , Vértebras Torácicas/cirurgia , Endoscópios , Resultado do Tratamento , Estudos Retrospectivos
20.
Environ Sci Pollut Res Int ; 30(11): 29281-29299, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36409408

RESUMO

The ambition of the Belt and Road Initiative (BRI) became an integral part of carbon emission abatement. The BRI impact on African participating countries' battle against carbon emissions intensity is a contentious subject. Urbanization and industrialization are the main sources of CO2 emissions in Africa and the driving force in the BRI. Using data on variables from 2010 to 2019 in 54 African countries, applying Difference-in-differences model (DID) and Propensity Score Matching-Difference-in-differences regression (PSM-DID), and robustness tests to investigate if the BRI's participation tends to reduce the carbon emissions intensity of African participating countries. This study finds that African countries' participation in the BRI minimizes the intensity of carbon emissions in those countries. Further analysis shows that low carbon development of BRI countries is more significant in countries that joined the BRI than those that did not join it. In addition, our results show that improving economic transformation such as the innovation in technology and industries' structures can boost the CO2 emission reduction technologies. These findings suggest that developing BRI collaboration with China will benefit the environment and African BRI participating countries' ability to achieve sustainable development. Our results further support the BRI's effect and recommend policy implications and methods for those countries' CO2 emission prevention and control actions.


Assuntos
Dióxido de Carbono , Carbono , Dióxido de Carbono/análise , Desenvolvimento Industrial , Desenvolvimento Econômico , África
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