Dynamic characteristic is presented by identifying the model and the dynamic parameters of a precise long stroke linear motor (PLSLM) with the air-bearing in optical lithography. The PLSLM is supported by air-bearin...Dynamic characteristic is presented by identifying the model and the dynamic parameters of a precise long stroke linear motor (PLSLM) with the air-bearing in optical lithography. The PLSLM is supported by air-bearing on the stator, and is driven by on-board two large linear motors in a cross-configuration. Firstly, a model of the PLSLM is established by finite element method (FEM). Secondly, based on the model, the natural frequencies and model shapes are discusse& And the contribution of each active mode is evaluated by computing the modal participation factors (MPF), which indicates the major vibration direction. Furthermore, by the experimental modal analysis, the experimental results are in agreement with simulation results, which it is sure that the FEM is reasonable. What's more, comparing with the effects on the frequency due to the air-bearing stiffness, the relations of the natural frequencies with the air-bearing stiffness are found. It is found that the frequency response curve is fluctuant with the air-bearing stiffness in each direction. Finally, it is conclusion that the natural frequency of the PLSLM is largely affected by the air-bearing stiffness variety. This research is contributed to the dynamic characteristics resulted from the air-beating stiffness. Further work will include better optimization on the dynamic parameter in the controller design through the control algorithm for the precise long stroke motor.展开更多
The equipment has a high and strict requirement of dynamic seals, especially working with Long stroke reciprocating motion under a sandy condition and with a great deal of gas. The seal form of power cylinder on the u...The equipment has a high and strict requirement of dynamic seals, especially working with Long stroke reciprocating motion under a sandy condition and with a great deal of gas. The seal form of power cylinder on the underground part of hydraulic power rodless type oil extraction equipment is studied. We design three seal structures, do the performance testing and the life testing with related equipment. It turned out that the seal form that combines gap seal with sand prevention techniques has high performance, longer life. The power cylinder works stably and reliably.展开更多
Introduction: Stroke is the leading cause of mortality and physical disability in sub-Saharan Africa. Objective: Determining medium-term and long-term mortality for stroke and identifying associated factors. Method: I...Introduction: Stroke is the leading cause of mortality and physical disability in sub-Saharan Africa. Objective: Determining medium-term and long-term mortality for stroke and identifying associated factors. Method: It consists in a cross-sectional, prospective, descriptive and analytical study that was conducted from April 1 to August 31, 2013 in the Neurology Department of CNHU-HKM in Cotonou. It involved patients who have known stroke for at least 6 months, and were all admitted and discharged later on. The disease survivors were re-contacted and examined again at home or at hospital. Then, the number of deceased was systematically recorded with precision of death time-limit. Results: The overall mortality rate was 29%. Mortality was higher with patients over 70 years with a frequency of 57.1%. The medium-term mortality rate was 25% against 4% for long-term. The average time-limit for death occurrence after the vascular incident was 7 months ± 6.4 months. Prognostic factors of mortality were: the age of the patient (IC95% = 7.73 [1.49 - 39.99], p = 0.015 ), marital status (IC95% = 0.27 [0.08 to 0.94], p = 0.039 ) and the presence of aphasia (IC95% = 5.52 [1.45 to 20.94 ], p = 0.012). Conclusion: Stroke mortality still remains significant, even after the patients have been discharged from hospital. A good psychological family support and efficient aphasia coverage are essential for its reduction.展开更多
OBJeCTIve:To systematically evaluate the long-term effect and safety ofXingnao Kaiqiao nee-dling method in ischemic stroke treatment. DATA ReTRIevAL: We retrieved relevant random and semi-random controlled trials th...OBJeCTIve:To systematically evaluate the long-term effect and safety ofXingnao Kaiqiao nee-dling method in ischemic stroke treatment. DATA ReTRIevAL: We retrieved relevant random and semi-random controlled trials that used theXingnao Kaiqiao needling method to treat ischemic stroke compared with various control treatments such as conventional drugs or other acupuncture therapies. Searched databases included China National Knowledge Infrastructure, Weipu Information Resources System, Wanfang Medical Data System, Chinese Biomedical Literature Database, Cochrane Library, and PubMed, from May 2006 to July 2014. SeLeCTION CRITeRIA: Two authors independently conducted literature screening, quality evaluation, and data extraction. The quality of articles was evaluated according to the Cochrane Reviewers’ Handbook 5.1, and the study was carried out using Cochrane system assessment methods. RevMan 5.2 was used for meta-analysis of the included studies. MAIN OUTCOMe MeASUReS: Mortality rate, recurrence rate, and disability rate were observed. ReSULTS:Nine randomized and semi-randomized controlled trials treating 931 cases of ischemic stroke were included in this review. Meta-analysis results showed that there were no sig-niifcant differences in mortality reduction (risk ratio (RR) = 0.58, 95% conifdence interval (CI): 0.17–1.93,Z = 0.89,P = 0.37) or recurrence rate (RR = 0.55, 95%CI: 0.18–1.70,Z = 1.04,P = 0.30) of ischemic stroke patients between theXingnao Kaiqiao needling and control treatment groups. However, theXingnao Kaiqiao needling method had a tendency towards higher efifcacy in mor-tality reduction and recurrence rates. TheXingnao Kaiqiao needling method was signiifcantly better than that of the control treatment in reducing disability rate (RR = 0.51, 95%CI: 0.27–0.98, Z = 2.03,P 〈 0.05). CONCLUSION:TheXingnao Kaiqiao needling method has a better effect than control treatment in reducing disability rate. The long-term effect ofXingnao Kaiqiao needling against ischemic stroke is better than that of control treatment. However, the limitations of this study limit the strength of the conclusions. Randomized controlled trials with a strict, reasonable design, and multi-center, large-scale samples and follow-up are necessary to draw conclusions aboutXingnao Kaiqiao needling.展开更多
Objective: As stroke mortality rates decline in Japan, a large proportion of disabled stroke survivors living in their homes are supported by informal caregivers or formal healthcare services. To evaluate the impact o...Objective: As stroke mortality rates decline in Japan, a large proportion of disabled stroke survivors living in their homes are supported by informal caregivers or formal healthcare services. To evaluate the impact of healthcare provision on outcome of stroke patients living at home, this study investigated the associations of long-term care and health-related quality of life (HRQOL) in patients 1 year after stroke onset. Methods: Data on patient and caregiver characteristics, HRQOL of patients, and healthcare services for those living at home were prospectively collected from 426 patients with stroke at baseline and 12 months. Using general measures of HRQOL, namely, Short Form-36 (SF-36) and EuroQOL 5 dimension (EQ-5D), multivariate regression models were used to determine the contribution of variables to changes in HRQOL scores from discharge to the first year after stroke. Results: Five domains of SF-36—role-physical, vitality, social functioning, role- emotional, and mental health—were significantly improved 1 year after stroke. Factors affecting changes in the five domains of HRQOL were age, independence in activities of daily living, and cognitive function. Home care service was positively associated with role-physical, social functioning, and role-emotional. In addition, home rehabilitation and home bathing services were positively associated with social functioning. Conclusion: This study clarified that improvements of HRQOL 1 year after stroke were associated with use of home-based services involving home care service, home rehabilitation, and home bathing services. The use of home-based services contributed to the improved welfare of patients living at home.展开更多
基金National Basic Research Program of China (973 Program,No.2003CB716206)National Natural Science Foundation of China (No.50605025)
文摘Dynamic characteristic is presented by identifying the model and the dynamic parameters of a precise long stroke linear motor (PLSLM) with the air-bearing in optical lithography. The PLSLM is supported by air-bearing on the stator, and is driven by on-board two large linear motors in a cross-configuration. Firstly, a model of the PLSLM is established by finite element method (FEM). Secondly, based on the model, the natural frequencies and model shapes are discusse& And the contribution of each active mode is evaluated by computing the modal participation factors (MPF), which indicates the major vibration direction. Furthermore, by the experimental modal analysis, the experimental results are in agreement with simulation results, which it is sure that the FEM is reasonable. What's more, comparing with the effects on the frequency due to the air-bearing stiffness, the relations of the natural frequencies with the air-bearing stiffness are found. It is found that the frequency response curve is fluctuant with the air-bearing stiffness in each direction. Finally, it is conclusion that the natural frequency of the PLSLM is largely affected by the air-bearing stiffness variety. This research is contributed to the dynamic characteristics resulted from the air-beating stiffness. Further work will include better optimization on the dynamic parameter in the controller design through the control algorithm for the precise long stroke motor.
文摘The equipment has a high and strict requirement of dynamic seals, especially working with Long stroke reciprocating motion under a sandy condition and with a great deal of gas. The seal form of power cylinder on the underground part of hydraulic power rodless type oil extraction equipment is studied. We design three seal structures, do the performance testing and the life testing with related equipment. It turned out that the seal form that combines gap seal with sand prevention techniques has high performance, longer life. The power cylinder works stably and reliably.
文摘Introduction: Stroke is the leading cause of mortality and physical disability in sub-Saharan Africa. Objective: Determining medium-term and long-term mortality for stroke and identifying associated factors. Method: It consists in a cross-sectional, prospective, descriptive and analytical study that was conducted from April 1 to August 31, 2013 in the Neurology Department of CNHU-HKM in Cotonou. It involved patients who have known stroke for at least 6 months, and were all admitted and discharged later on. The disease survivors were re-contacted and examined again at home or at hospital. Then, the number of deceased was systematically recorded with precision of death time-limit. Results: The overall mortality rate was 29%. Mortality was higher with patients over 70 years with a frequency of 57.1%. The medium-term mortality rate was 25% against 4% for long-term. The average time-limit for death occurrence after the vascular incident was 7 months ± 6.4 months. Prognostic factors of mortality were: the age of the patient (IC95% = 7.73 [1.49 - 39.99], p = 0.015 ), marital status (IC95% = 0.27 [0.08 to 0.94], p = 0.039 ) and the presence of aphasia (IC95% = 5.52 [1.45 to 20.94 ], p = 0.012). Conclusion: Stroke mortality still remains significant, even after the patients have been discharged from hospital. A good psychological family support and efficient aphasia coverage are essential for its reduction.
基金financially supported by grants from Hebei Province Engineering Talent Cultivation Project and Hebei Province Science and Technology Research and Development Projects,No.11276103D-35
文摘OBJeCTIve:To systematically evaluate the long-term effect and safety ofXingnao Kaiqiao nee-dling method in ischemic stroke treatment. DATA ReTRIevAL: We retrieved relevant random and semi-random controlled trials that used theXingnao Kaiqiao needling method to treat ischemic stroke compared with various control treatments such as conventional drugs or other acupuncture therapies. Searched databases included China National Knowledge Infrastructure, Weipu Information Resources System, Wanfang Medical Data System, Chinese Biomedical Literature Database, Cochrane Library, and PubMed, from May 2006 to July 2014. SeLeCTION CRITeRIA: Two authors independently conducted literature screening, quality evaluation, and data extraction. The quality of articles was evaluated according to the Cochrane Reviewers’ Handbook 5.1, and the study was carried out using Cochrane system assessment methods. RevMan 5.2 was used for meta-analysis of the included studies. MAIN OUTCOMe MeASUReS: Mortality rate, recurrence rate, and disability rate were observed. ReSULTS:Nine randomized and semi-randomized controlled trials treating 931 cases of ischemic stroke were included in this review. Meta-analysis results showed that there were no sig-niifcant differences in mortality reduction (risk ratio (RR) = 0.58, 95% conifdence interval (CI): 0.17–1.93,Z = 0.89,P = 0.37) or recurrence rate (RR = 0.55, 95%CI: 0.18–1.70,Z = 1.04,P = 0.30) of ischemic stroke patients between theXingnao Kaiqiao needling and control treatment groups. However, theXingnao Kaiqiao needling method had a tendency towards higher efifcacy in mor-tality reduction and recurrence rates. TheXingnao Kaiqiao needling method was signiifcantly better than that of the control treatment in reducing disability rate (RR = 0.51, 95%CI: 0.27–0.98, Z = 2.03,P 〈 0.05). CONCLUSION:TheXingnao Kaiqiao needling method has a better effect than control treatment in reducing disability rate. The long-term effect ofXingnao Kaiqiao needling against ischemic stroke is better than that of control treatment. However, the limitations of this study limit the strength of the conclusions. Randomized controlled trials with a strict, reasonable design, and multi-center, large-scale samples and follow-up are necessary to draw conclusions aboutXingnao Kaiqiao needling.
文摘Objective: As stroke mortality rates decline in Japan, a large proportion of disabled stroke survivors living in their homes are supported by informal caregivers or formal healthcare services. To evaluate the impact of healthcare provision on outcome of stroke patients living at home, this study investigated the associations of long-term care and health-related quality of life (HRQOL) in patients 1 year after stroke onset. Methods: Data on patient and caregiver characteristics, HRQOL of patients, and healthcare services for those living at home were prospectively collected from 426 patients with stroke at baseline and 12 months. Using general measures of HRQOL, namely, Short Form-36 (SF-36) and EuroQOL 5 dimension (EQ-5D), multivariate regression models were used to determine the contribution of variables to changes in HRQOL scores from discharge to the first year after stroke. Results: Five domains of SF-36—role-physical, vitality, social functioning, role- emotional, and mental health—were significantly improved 1 year after stroke. Factors affecting changes in the five domains of HRQOL were age, independence in activities of daily living, and cognitive function. Home care service was positively associated with role-physical, social functioning, and role-emotional. In addition, home rehabilitation and home bathing services were positively associated with social functioning. Conclusion: This study clarified that improvements of HRQOL 1 year after stroke were associated with use of home-based services involving home care service, home rehabilitation, and home bathing services. The use of home-based services contributed to the improved welfare of patients living at home.