Objective:To provide anatomical datum for intrusive operations of lumbar intervertebral foramen,especially that using acupuncture-knife as intrusive tool.Methods:To dissect 10 antisepsis cadavers and observe the expos...Objective:To provide anatomical datum for intrusive operations of lumbar intervertebral foramen,especially that using acupuncture-knife as intrusive tool.Methods:To dissect 10 antisepsis cadavers and observe the exposed blood vessels,ligaments,nerves and their adjacent relations in L1/2~L5/S1intervertebral foramen.Results:Lumbar intervertebral foramen exit zones were almost sealed by nerves and blood vessels.There were two zones with relatively no blood vessel and nerve(triangular working zones)located in the midpoint of the distance between two adjacent roots of transverse processus,and clung to lamina of vertebral arch,and they were also found upon the margo superior of the root of transverse processus,but the ascending lumbar vein or(and)the rami anastomoticus between the remi inferior of intervertebral vein and lumbar veins were observed in 12%triangular working zones upon the margo superior of root of transverse processus.Conclusions:"Triangular working zone"was relatively avascular zone.Pay attention to the possibilty of presence of blood vessels on the entrance passage of intrusive operations on lumbar side rear.The needlepoint should be pierced at the midpoint of the distance between two adjacent roots of transverse processus and cling to the outer edge of lamina of vertebral arch when doing the foraminal lumbar puncture.As lumbar intervertebral foramina exit zone was almost sealed by nerves and blood vessels,blind incising and debonding with acupuncture-knife in this area was relatively much more dangerous.展开更多
Background: Inadequate human resources are a major constraint to improving global health. The health sector is characterized by a high turnover coupled with internal as well as external brain drain but there is little...Background: Inadequate human resources are a major constraint to improving global health. The health sector is characterized by a high turnover coupled with internal as well as external brain drain but there is little information on intention to leave among health professionals in public health centers of Jimma Zone, Oromia Regional State. The aim of this study is to assess intention to leave and associated factors among health professionals in public health centers of Jimma Zone, southwest Ethiopia. Methods: A cross-sectional quantitative and qualitative study was conducted on seven randomly selected woredas (districts) which have 53 public health centers. All health professionals in sampled district public health centers were included (n = 505). Factor analysis was employed for all Likert scale instruments to extract factor(s) representing each of the scales using SPSS version 16.0. The qualitative data was analyzed by thematic analysis methods. Ethical approval was obtained from Jimma University. Results: Four hundred fifty five (90.1%) health professionals participated in the study;out of this, 290 (63.7%) had intention to leave. Among variables, job satisfaction (Beta = -0.298, (95% CI, -0.568 to -0.029), working environment (Beta = -0.612, (95% CI, -0.955 to -0.270), and organizational management (Beta = -0.552, (95% CI, 0.289 to 0.815) had statistically significant association with intention to leave among health professionals in public health centers of Jimma Zone. Conclusions: The overall intention to leave among health professionals was high. Level of job satisfaction, working environment, work pressure, and organizational management had statistically significant association with intention to leave. Thus, responsible bodies should aggressively work on the concerns identified, like, improvements in salary, promotion in terms of training/educational opportunity, improving working environment, and transfer of health professionals, and improvement of the leadership skills of managers.展开更多
The energy efficiency of proton exchange membrane (PEM) fuel cells always keeps changing with load and time. Considering cell diversity and operation variety, it’s of necessity to find a simple method to estimate the...The energy efficiency of proton exchange membrane (PEM) fuel cells always keeps changing with load and time. Considering cell diversity and operation variety, it’s of necessity to find a simple method to estimate the changes. The work is done with the recently developed ideal cell model on behalf of various real cells, and results in a complete set of efficiency formulae including one for the instantaneous and three for the average. The formulae stand for a volt-ampere method which permits the average efficiency to be estimated in the form of state function of cell output like the instantaneous efficiency. With cell constants for cell specialty representation in this method, the formulae can extend to cover various real cells and make it realized to broadly overview the instantaneous and average efficiency movements with both load and time throughout cell operating ranges. The energy efficiency formulization and overviews may help make clear the correlative parameters with the efficiency, help deepen acquaintance with efficiency change and assist in cell operation optimization.展开更多
This paper is dedicated to analytical expression of the maximum electricity-cost ratio (M-ECR) point of the proton exchange membrane (PEM) fuel cell power generation as the function of cell constants and cost constant...This paper is dedicated to analytical expression of the maximum electricity-cost ratio (M-ECR) point of the proton exchange membrane (PEM) fuel cell power generation as the function of cell constants and cost constants. That is to formulize the maximum cost performance (MCP) magnitude and the optimal final operating (OFO) location in the working zone based on the five-constant ideal cell model and the two-constant cost model. The issues are well resolved by introducing the concepts of economic voltage and cost factor and describing the movement of the M-ECR point with cost factor. According to mathematical derivations, the movement can be described in the form of MCP and OFO curves. The derivations lead to a complete set of discriminants and criteria of the M-ECR point of PEM fuel cells that theoretically cover all of cell specialties and all of cost specialties. The discriminants and criteria may act as a general tool for the operation optimization of a diversity of PEM fuel cells and the economic viability estimation of the power generation.展开更多
文摘Objective:To provide anatomical datum for intrusive operations of lumbar intervertebral foramen,especially that using acupuncture-knife as intrusive tool.Methods:To dissect 10 antisepsis cadavers and observe the exposed blood vessels,ligaments,nerves and their adjacent relations in L1/2~L5/S1intervertebral foramen.Results:Lumbar intervertebral foramen exit zones were almost sealed by nerves and blood vessels.There were two zones with relatively no blood vessel and nerve(triangular working zones)located in the midpoint of the distance between two adjacent roots of transverse processus,and clung to lamina of vertebral arch,and they were also found upon the margo superior of the root of transverse processus,but the ascending lumbar vein or(and)the rami anastomoticus between the remi inferior of intervertebral vein and lumbar veins were observed in 12%triangular working zones upon the margo superior of root of transverse processus.Conclusions:"Triangular working zone"was relatively avascular zone.Pay attention to the possibilty of presence of blood vessels on the entrance passage of intrusive operations on lumbar side rear.The needlepoint should be pierced at the midpoint of the distance between two adjacent roots of transverse processus and cling to the outer edge of lamina of vertebral arch when doing the foraminal lumbar puncture.As lumbar intervertebral foramina exit zone was almost sealed by nerves and blood vessels,blind incising and debonding with acupuncture-knife in this area was relatively much more dangerous.
文摘Background: Inadequate human resources are a major constraint to improving global health. The health sector is characterized by a high turnover coupled with internal as well as external brain drain but there is little information on intention to leave among health professionals in public health centers of Jimma Zone, Oromia Regional State. The aim of this study is to assess intention to leave and associated factors among health professionals in public health centers of Jimma Zone, southwest Ethiopia. Methods: A cross-sectional quantitative and qualitative study was conducted on seven randomly selected woredas (districts) which have 53 public health centers. All health professionals in sampled district public health centers were included (n = 505). Factor analysis was employed for all Likert scale instruments to extract factor(s) representing each of the scales using SPSS version 16.0. The qualitative data was analyzed by thematic analysis methods. Ethical approval was obtained from Jimma University. Results: Four hundred fifty five (90.1%) health professionals participated in the study;out of this, 290 (63.7%) had intention to leave. Among variables, job satisfaction (Beta = -0.298, (95% CI, -0.568 to -0.029), working environment (Beta = -0.612, (95% CI, -0.955 to -0.270), and organizational management (Beta = -0.552, (95% CI, 0.289 to 0.815) had statistically significant association with intention to leave among health professionals in public health centers of Jimma Zone. Conclusions: The overall intention to leave among health professionals was high. Level of job satisfaction, working environment, work pressure, and organizational management had statistically significant association with intention to leave. Thus, responsible bodies should aggressively work on the concerns identified, like, improvements in salary, promotion in terms of training/educational opportunity, improving working environment, and transfer of health professionals, and improvement of the leadership skills of managers.
文摘The energy efficiency of proton exchange membrane (PEM) fuel cells always keeps changing with load and time. Considering cell diversity and operation variety, it’s of necessity to find a simple method to estimate the changes. The work is done with the recently developed ideal cell model on behalf of various real cells, and results in a complete set of efficiency formulae including one for the instantaneous and three for the average. The formulae stand for a volt-ampere method which permits the average efficiency to be estimated in the form of state function of cell output like the instantaneous efficiency. With cell constants for cell specialty representation in this method, the formulae can extend to cover various real cells and make it realized to broadly overview the instantaneous and average efficiency movements with both load and time throughout cell operating ranges. The energy efficiency formulization and overviews may help make clear the correlative parameters with the efficiency, help deepen acquaintance with efficiency change and assist in cell operation optimization.
文摘This paper is dedicated to analytical expression of the maximum electricity-cost ratio (M-ECR) point of the proton exchange membrane (PEM) fuel cell power generation as the function of cell constants and cost constants. That is to formulize the maximum cost performance (MCP) magnitude and the optimal final operating (OFO) location in the working zone based on the five-constant ideal cell model and the two-constant cost model. The issues are well resolved by introducing the concepts of economic voltage and cost factor and describing the movement of the M-ECR point with cost factor. According to mathematical derivations, the movement can be described in the form of MCP and OFO curves. The derivations lead to a complete set of discriminants and criteria of the M-ECR point of PEM fuel cells that theoretically cover all of cell specialties and all of cost specialties. The discriminants and criteria may act as a general tool for the operation optimization of a diversity of PEM fuel cells and the economic viability estimation of the power generation.