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2.
Math Biosci Eng ; 17(4): 2970-2983, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32987511

RESUMO

Computational models and inverse dynamic optimization methods are used to predict in-vivo spinal loading. Spinal force is conventionally predicted using the constant loading path method, which is based on the concept that the physiological directions of the spine loads follow the same path of the spinal curve. However, the global convergence optimization method, in which the instantaneous center of rotation of the joint should be also predicted, is necessary for accurate prediction of joint forces of the human body. In this study, we investigate the joint forces, instantaneous centers of rotation, and muscle forces of the human lumbar spine using both global convergence optimization method and constant loading path method during flexion, upright standing, and extension postures. The joint forces predicted using the constant loading path method were 130%, 234%, and 253% greater than those predicted using the global convergence optimization method for the three postures. The instantaneous centers of rotation predicted using the global convergence optimization method were segment level-dependent and moved anteriorly in the flexion and posteriorly in the extension, whereas those predicted using the constant loading path method moved posteriorly in both the flexion and extension. The data indicated that compared to the global convergence optimization method, the constant loading path method introduces additional constraints to the spinal joint model, and thus, it results in greater joint and muscle forces.


Assuntos
Vértebras Lombares , Postura , Fenômenos Biomecânicos , Humanos , Amplitude de Movimento Articular , Rotação
3.
Ying Yong Sheng Tai Xue Bao ; 28(11): 3627-3633, 2017 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-29692106

RESUMO

A long-term fertilizer experiment was conducted to determine the precise effects of nitrogen (N) fertilization on the yield and quality of cucumber, which were grown in greenhouse located in the coastal hilly region of East China. This work included four treatments with varying levels of chemical N application (N1, 800 kg·hm-2, N2, 600 kg·hm-2 and N3, 400 kg·hm-2, CK, no fertilization) plus ON (organic N 400 kg·hm-2). Results showed that a 50% reduction of N fertilization (N3) produced no significant effects on yield, when compared with the local conventional practice (N1). Importantly, fruit nitrate content for cucumbers with N fertilization ranged from 94.2 to 136.1 mg·kg-1, which was acceptable according to the National Food Safety Standard of China. However, when compared with no fertilization control, N fertilization increased nitrate content by 18.1%-44.5%. Chemical N fertilization resulted in a decrease of vitamin C, soluble sugar and soluble protein contents in cucumber, and caused significant temporary changes of soil pH and other chemical and physical properties of the soil. No significant correlations were found between cucumber yields, economic benefit and soil property variables under the excessive use of N fertilizer. It was concluded that N fertilization could be reduced by half with no significant reduction of fruit yield and quality for cucumbers cultivated in greenhouse located in the coastal hilly region of East China.


Assuntos
Cucumis sativus , Fertilizantes , Nitrogênio , Agricultura , China , Frutas , Solo
4.
ACS Nano ; 10(9): 8632-44, 2016 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-27603024

RESUMO

Phosphorus-rich transition metal phosphide CuP2 nanowires were synthesized with high quality and high yield (∼60%) via the supercritical fluid-liquid-solid (SFLS) growth at 410 °C and 10.2 MPa. The obtained CuP2 nanowires have a high aspect ratio and exhibit a single crystal structure of monoclinic CuP2 without any impurity phase. CuP2 nanowires have progressive improvement for semiconductors and energy storages compared with bulk CuP2. Being utilized for back-gate field effect transistor (FET) measurement, CuP2 nanowires possess a p-type behavior intrinsically with an on/off ratio larger than 10(4) and its single nanowire electrical transport property exhibits a hole mobility of 147 cm(2) V(-1) s(-1), representing the example of a CuP2 transistor. In addition, CuP2 nanowires can serve as an appealing anode material for a lithium-ion battery electrode. The discharge capacity remained at 945 mA h g(-1) after 100 cycles, showing a good capacity retention of 88% based on the first discharge capacity. Even at a high rate of 6 C, the electrode still exhibited an outstanding result with a capacity of ∼600 mA h g(-1). Ex-situ transmission electron microscopy and CV tests demonstrate that the stability of capacity retention and remarkable rate capability of the CuP2 nanowires electrode are attributed to the role of the metal phosphide conversion-type lithium storage mechanism. Finally, CuP2 nanowire anodes and LiFePO4 cathodes were assembled into pouch-type lithium batteries offering a capacity over 60 mA h. The full cell shows high capacity and stable capacity retention and can be used as an energy supply to operate electronic devices such as mobile phones and mini 4WD cars.

5.
ACS Appl Mater Interfaces ; 8(20): 13009-17, 2016 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-27144911

RESUMO

Large-area conducting transparent conducting electrodes (TCEs) were prepared by a fast, scalable, and low-cost spray deposition of copper nanowire (CuNW) dispersions. Thin, long, and pure copper nanowires were obtained via the seed-mediated growth in an organic solvent-based synthesis. The mean length and diameter of nanowires are, respectively, 37.7 µm and 46 nm, corresponding to a high-mean-aspect ratio of 790. These wires were spray-deposited onto a glass substrate to form a nanowire conducting network which function as a TCE. CuNW TCEs exhibit high-transparency and high-conductivity since their relatively long lengths are advantageous in lowering in the sheet resistance. For example, a 2 × 2 cm(2) transparent nanowire electrode exhibits transmittance of T = 90% with a sheet resistance as low as 52.7 Ω sq(-1). Large-area sizes (>50 cm(2)) of CuNW TCEs were also prepared by the spray coating method and assembled as resistive touch screens that can be integrated with a variety of devices, including LED lighting array, a computer, electric motors, and audio electronic devices, showing the capability to make diverse sizes and functionalities of CuNW TCEs by the reported method.

6.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(7): 804-7, 2014 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-25137844

RESUMO

OBJECTIVE: To observe the analgesic effect and safety of acupuncture-anesthetic composite anesthesia (AACA) in hysteroscopic surgery. METHODS: Totally 93 patients undergoing hysteroscopic surgery were randomly assigned to the intravenous anesthesia group (A group, 30 cases), the AACA group (B group, 32 cases), and the acupuncture combined with intravenous anesthesia group (C group, 31 cases). Patients in Group A were anesthetized by sufentanil combined propofol. Those in Group B were anesthetized by sufentanil combined acupuncture. Those in Group C were anesthetized by sufentanil, propofol combined acupuncture. Yinlian and Ququan (LR8) were needled for patients in Group B and C. The peri-operative mean arterial pressure (MAP), heart rate (HR), and oxygen saturation (SpO2), the surgical time, the recovery time, the sufentanil and propofol dosages, adverse anesthesia reactions were observed. Meanwhile, the OAA/S score, Ramsay sedation score, and Visual Analogue Score (VAS) were also measured. RESULTS: Compared with Group A and C, patients in Group B were awake, with obvious increased OAA/S score (P < 0.01). Ramsay sedation score was significantly lower (P < 0.01).The MAP and HR were elevated (P < 0.05). The patient case of SpO2 less than 85% during the operation decreased (P < 0.05). The incidence of postoperative dizziness was reduced (P < 0.05). Compared with Group A, the propofol consumption decreased in Group C (P < 0.05). There was no statistical difference in the operation time, the sufentanil dosage, VAS score, the incidence of postoperative nause- a and vomiting among the three groups (P > 0.05). CONCLUSIONS: The patients were awake in AACA. The intraoperative sedation was better than that obtained by intravenous anesthesia. But the analgesic effect was similar to that obtained by intravenous anesthesia.


Assuntos
Analgesia por Acupuntura , Analgesia/métodos , Histeroscopia , Adulto , Anestesia Intravenosa , Feminino , Humanos , Adulto Jovem
7.
Nanoscale ; 5(20): 9875-81, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-23979254

RESUMO

There is strong and growing interest in applying metal silicide nanowires as building blocks for a new class of silicide-based applications, including spintronics, nano-scale interconnects, thermoelectronics, and anti-reflective coating materials. Solution-phase environments provide versatile materials chemistry as well as significantly lower production costs compared to gas-phase synthesis. However, solution-phase synthesis of silicide nanowires remains challenging due to the lack of fundamental understanding of silicidation reactions. In this study, single-crystalline Cu3Si nanowire arrays were synthesized in an organic solvent. Self-catalyzed, dense single-crystalline Cu3Si nanowire arrays were synthesized by thermal decomposition of monophenylsilane in the presence of copper films or copper substrates at 420 to 475 °C and 10.3 MPa in supercritical benzene. The solution-grown Cu3Si nanowire arrays serve dual functions as field emitters and anti-reflective layers, which are reported on copper silicide materials for the first time. Cu3Si nanowires exhibit superior field-emission properties, with a turn-on-voltage as low as 1.16 V µm(-1), an emission current density of 8 mA cm(-2) at 4.9 V µm(-1), and a field enhancement factor (ß) of 1500. Cu3Si nanowire arrays appear black with optical absorption less than 5% between 400 and 800 nm with minimal reflectance, serving as highly efficient anti-reflective layers. Moreover, the Cu3Si nanowires could be grown on either rigid or flexible substrates (PI). This study shows that solution-phase silicide reactions are adaptable for high-quality silicide nanowire growth and demonstrates their promise towards fabrication of metal silicide-based devices.

8.
Zhonghua Zhong Liu Za Zhi ; 34(5): 382-4, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22883462

RESUMO

OBJECTIVE: To improve the understanding of thymic neuroendocrine carcinoma (TNC) by retrospective analysis of the clinical data of 21 cases. METHODS: The clinical data of 21 patients with TNC treated in the Peking Union Medical College Hospital from 1998 to 2010 were retrospectively analyzed. RESULTS: There were 12 males and 9 females, with onset age ranging from 13 to 67 years and the mean age of 43 years. The clinical manifestation was diverse, in which the malaise of chest and back accounted for 57.1% (12/21), Cushing's syndrome 33.3% (7/21), multiple endocrine neoplasia type 1 accounted for 4.8% (1/21), pharyngeal malaise 4.8%, superior vena cava syndrome 4.8% (1/21) and asymptomatic patients accounted for 4.8% (1/21). Eighteen of them demonstrated metastasis, in which 13 had metastasis to lymph nodes and local vascular invasion, 9 to lung or pleura, 5 to bone, 1 to liver and 1 was recurred in situ. Twenty of them were treated by surgical resection. Eleven of them received radiotherapy and 9 chemotherapy after surgery. One patient was too severe to endure surgery, and was a treated by chemotherapy only. CONCLUSION: TNC is rare, and its clinical features are complex, with a high level of malignancy. The first choice of treatment is resection. Adjuvant radiotherapy and/or chemotherapy may be applied in patients with metastasis.


Assuntos
Carcinoma Neuroendócrino/patologia , Timectomia , Neoplasias do Timo/patologia , Adolescente , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Idoso , Neoplasias Ósseas/secundário , Carcinoma Neuroendócrino/metabolismo , Carcinoma Neuroendócrino/secundário , Carcinoma Neuroendócrino/cirurgia , Carcinoma Neuroendócrino/terapia , Quimioterapia Adjuvante , Síndrome de Cushing/metabolismo , Síndrome de Cushing/patologia , Síndrome de Cushing/cirurgia , Síndrome de Cushing/terapia , Feminino , Humanos , Hidrocortisona/metabolismo , Imuno-Histoquímica , Neoplasias Pulmonares/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 1/metabolismo , Neoplasia Endócrina Múltipla Tipo 1/patologia , Neoplasia Endócrina Múltipla Tipo 1/cirurgia , Neoplasia Endócrina Múltipla Tipo 1/terapia , Radioterapia Adjuvante , Estudos Retrospectivos , Neoplasias do Timo/metabolismo , Neoplasias do Timo/cirurgia , Neoplasias do Timo/terapia , Adulto Jovem
9.
Nanoscale ; 4(15): 4562-70, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22699842

RESUMO

Nanocrystal-graphene have been proposed as a new kind of promising hybrid for a wide range of application areas including catalysts, electronics, sensors, biomedicine, and energy storage, etc. Although a variety of methods have been developed for the preparation of hybrids, a facile and general synthetic approach is still highly required. In this study, nanocrystal-graphene hybrids were successfully synthesized in high-boiling-point organic solvents. Graphene oxide (GO) nanosheets were modified by oleylamine (OLA) to form a OLA-GO complex in order to be readily incorporated into hydrophobic synthesis. A rich library of highly crystalline nanocrystals, with types including noble metal, metal oxide, magnetic material and semiconductor were successfully grown on chemically converted graphene (CCG), which is simultaneously reduced from GO during the synthesis. High boiling-point solvents afford sufficient thermal energy to assure the high-quality crystalline nature of NCs, therefore the post-annealing process is obviated. Controlled experiments revealed that OLA-GO triggers heterogeneous nucleation and serves as excellent nuclei anchorage media. The protocol developed here brings one step closer to achieve "unity in diversity" on the preparation of nanocrystal-graphene hybrids.


Assuntos
Grafite/química , Nanopartículas/química , Solventes/química , Aminas/química , Interações Hidrofóbicas e Hidrofílicas , Magnetismo , Metais/química , Óxidos/química
10.
Zhonghua Jie He He Hu Xi Za Zhi ; 35(1): 45-9, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22455943

RESUMO

OBJECTIVE: To improve the understanding of allergic granulomatous vasculitis, also called Churg-Strauss syndrome (CSS). METHODS: The clinical data, including clinical manifestations, laboratory findings, and pathology, of 25 patients with CSS were retrospectively investigated. RESULTS: There were 15 males and 10 females, aging 18 to 72 years (mean 45 ± 16). The clinical manifestations of CSS featured involvement of multiple systems or organs including respiratory system, nervous system, skin, digestive system, heart, and kidney. Eighty percent (20/25) of CSS patients had asthma as their first symptom, whereas 96.0% (24/25) had asthma in the whole course of CSS. The involvement of nasosinusitis of CSS was multi-group and the maxillary sinuses were the most frequently involved, which accounted for 61.1% (11/18). The peripheral nerves were involved in 72.7% (16/22) of patients and the most common manifestation was cerebrovascular event. Skin disease occurred in 60.0% (15/25), whereas heart involvement in 48.0% (12/25), renal involvement in 48.0% (12/25) and digestive system involvement in 32.0% (8/25) of the patients. The positive rate of IgE was 90.0% (18/20), and that of ANCA was 32.0% (8/25), with P-ANCA as the predominant. The main presentation of chest CT scan was patchy infiltration, mostly bilateral, which amounted for 71.4% (15/21). The change in electromyography was mononeuritis multiplex, of which the peroneal nerves and popliteal nerves were the most frequently involved. Electrocardiography of the CSS patients was always normal whereas the echocardiograms showed abnormal finds in 70.0% (14/20) of the patients. The pathological manifestations were necrotizing vasculitis, eosinophilic tissue infiltration, and extravascular granulomas. CONCLUSION: The clinical manifestations of CSS are diverse and complex, with a lack of pathognomonic symptoms. Clinical manifestations, auxiliary examinations and pathology are often required to make a diagnosis. Early diagnosis and treatment will be helpful for a better prognosis.


Assuntos
Síndrome de Churg-Strauss/diagnóstico , Síndrome de Churg-Strauss/terapia , Adolescente , Adulto , Idoso , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
11.
Progress in Modern Biomedicine ; (24): 858-861, 2008.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-737076

RESUMO

The complete nucleotide sequence of a cDNA clone encoding weever ribosomal protein L8, WeevL8, is described here. The WeevL8 cDNA has 848 nucleotides in full length and encodes a 257 amino-acid protein with a calculated molecular mass of 28.02 kDa. Two conserved domains have been identified in WEEVL8. It was concluded fromsequence alignment that WeevL8 gene was quite conservative, consistent with its role as a house-keeping gene. A phylogenetic analysis made by L8 protein showed the similar phylogenetic relationship to that with 18s rDNA. The high similarity supports the notion that ribosomal protein L8 can also be used as phylogenetic criterion.

12.
Progress in Modern Biomedicine ; (24): 858-861, 2008.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-735608

RESUMO

The complete nucleotide sequence of a cDNA clone encoding weever ribosomal protein L8, WeevL8, is described here. The WeevL8 cDNA has 848 nucleotides in full length and encodes a 257 amino-acid protein with a calculated molecular mass of 28.02 kDa. Two conserved domains have been identified in WEEVL8. It was concluded fromsequence alignment that WeevL8 gene was quite conservative, consistent with its role as a house-keeping gene. A phylogenetic analysis made by L8 protein showed the similar phylogenetic relationship to that with 18s rDNA. The high similarity supports the notion that ribosomal protein L8 can also be used as phylogenetic criterion.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-276872

RESUMO

The study was aimed to generate monoclonal antibodies (mAbs) against homo sapiens UDP-glucose pyrophosphorylase 2 (UGP2). Normal human liver tissues homogenized, and cytosolic proteins isolated by centrifugation were used to immunize BALB/c mice to generate mAbs by hybridoma technique. The mAbs were identified by ELISA, Western blot, and immunohistochemistry assay. The antibody specificity was confirmed by Uni-ZAP expression library screening. The results indicated that one hybridoma BAD062 secreting specific mAb against UGP2 was established. The Ig subclass of this mAb was IgG(2b) (kappa), and it could be used in ELISA, Western blot, immunohistochemistry assay. The antigen recognized by BAD062 mAb was localized in the hepatocyte cytoplasm, with molecular weight of 56 kD in the cytosolic proteins of human liver tissue. The BAD062 mAb was further confirmed by immunoscreening of Uni-ZAP XR liver cDNA expression library. It is concluded that a hybridoma cell line stably secretes specific mAb against UGP2. This mAb reacted with UGP2 in ELISA, Western blot, immunohistochemistry assay, and would be very useful for the UGP2 studies.


Assuntos
Animais , Humanos , Camundongos , Anticorpos Monoclonais , Especificidade de Anticorpos , Sequência de Bases , Hibridomas , Secreções Corporais , Fígado , Metabolismo , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , UTP-Glucose-1-Fosfato Uridililtransferase , Alergia e Imunologia
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