Objectives:In the sphere of occupational intensity,nursing stands recognized for its inherently demanding nature,marked by a rapid succession of tasks.Our primary aim was to assess the level of job intensity within nu...Objectives:In the sphere of occupational intensity,nursing stands recognized for its inherently demanding nature,marked by a rapid succession of tasks.Our primary aim was to assess the level of job intensity within nursing by analyzing the frequency and duration of activities performed by nurses,instances of task overlap,and the distribution of break times within a primary healthcare center.Methods:This study was conducted using a descriptive working method.Nursing activities were recorded with the observation of six nurses,each monitored for 37.5 h.We used the Maribor System for measuring Quantity in Nursing Care in Primary Health Care Settings to measure the nursing care activities about direct patient care,indirect patient care,and other unproductive aspects through direct non-participant observations.Results:About 41.5%(n=1,640)of all nursing activities involving direct contact with patients,about 38.2%(n=1,508)was indirect patient care,where a large amount worked with paper files(n=666,16.9%).In addition,about 15.0%were other nursing activities(mostly computer work),and just 5.3%(n=210)of tasks were unproductive.The observational findings indicate a pronounced level of work intensity experienced by nurses in primary health clinics.Significantly,nurses were predominantly engaged in direct patient care tasks,often managing multiple activities simultaneously.Their transitions between tasks occurred approximately every 3 min,frequently without adequate intervals for breaks.Conclusions:This study highlights the need to shift nurses’focus from a task-centric approach to one centered on patient care.The prevailing emphasis on tasks may contribute to enduring fatigue and professional dissatisfaction.Consequently,there is an urgent need to redefine the scope of a nurse’s role and implement a comprehensive computer information system as an integral part of this redefined approach.展开更多
The catalytic performance on jarosite process of jarosite seeds via biosynthesis and chemical processes were studied, respectively. The SEM and XRD results showed that biosynthetic jarosite seeds (BIO seeds) had smo...The catalytic performance on jarosite process of jarosite seeds via biosynthesis and chemical processes were studied, respectively. The SEM and XRD results showed that biosynthetic jarosite seeds (BIO seeds) had smooth surface and mainly consisted of potassium jarosite. The chemical synthesis jarosite seeds (CHM seeds) had a loose cauliflower-like surface and mainly consisted of hydronium jarosite. The catalytic performance of BIO seeds was better than that of CHM seeds on the formation of final jarosite product. The induction time can be shortened to 20 min, the reaction temperature can be reduced to only 75 ℃, and the initial reaction speed was enhanced obviously, up to 3.933%/min. The crystallinity of final jarosite product using BIO seeds can achieve 97.22%, while it was only 12.89% without seeds. This indicates that the precipitation process of jarosite is more complete with BIO seeds.展开更多
Psychophysical experiments on human and animal subjects have proven that aged individuals show significantly reduced visual contrast sensitivity compared with young adults.To uncover the possible neural mechanisms,we ...Psychophysical experiments on human and animal subjects have proven that aged individuals show significantly reduced visual contrast sensitivity compared with young adults.To uncover the possible neural mechanisms,we used extracellular single-unit recording techniques to examine the response of V1(primary visual cortex) neurons as a function of visual stimulus contrast in both old and young adult cats(Felis catus).The mean contrast sensitivity of V1 neurons to visual stimuli in old cats decreased significantly relative to young adult cats,consistent with findings reported in old primates.These results indicate that aging can affect contrast sensitivity of visual cortical cells in both primate and non-primate mammalian animals,and might contribute to the reduction of perceptual visual contrast sensitivity in aged individuals.Further,V1 cells of old cats exhibited increased responsiveness,decreased signal-to-noise ratio,and enlarged receptive field(RF) size compared with that of young adult cats,which indicated that decreased contrast sensitivity of V1 neurons accompanied a reduction of intracortical inhibition during senescence.展开更多
Serious stretch appears in shallow long offsset signals after NMO correction. In this article we study the generation mechanism of NMO stretch, demonstrate that the conventional travel time equation cannot accurately ...Serious stretch appears in shallow long offsset signals after NMO correction. In this article we study the generation mechanism of NMO stretch, demonstrate that the conventional travel time equation cannot accurately describe the travel time of the samples within the same reflection wavelet. As a result, conventional NMO inversion based on the travel time of the wavelet's central point occurs with errors. In this article, a travel time equation for the samples within the same wavelet is reconstructed through our theoretical derivation (the shifted first arrival point travel time equation), a new NMO inversion method based on the wavelet's first arrival point is proposed. While dealing with synthetic data, the semblance coefficient algorithm equation is modified so that wavelet first arrival points can be extracted. After that, NMO inversion based on the new velocity analysis is adopted on shot offset records. The precision of the results is significantly improved compared with the traditional method. Finally, the block move NMO correction based on the first arrival points travel times is adopted on long offset records and non-stretched results are achieved, which verify the proposed new equation.展开更多
The non-linear effects of different initial melt temperatures on the microstructure evolution during the solidification process of liquid Mg7Zn3 alloys were investigated by molecular dynamics simulation, The microstru...The non-linear effects of different initial melt temperatures on the microstructure evolution during the solidification process of liquid Mg7Zn3 alloys were investigated by molecular dynamics simulation, The microstructure transformation mechanisms were analyzed by several methods. The system was found to be solidified into amorphous structures from different initial melt temperatures at the same cooling rate of 1×10^12 K/s, and the 1551 bond-type and the icosahedron basic cluster (12 0 12 0 ) played a key role in the microstructure transition. Different initial melt temperatures had significant effects on the final microstructures. These effects only can be clearly observed below the glass transition temperature Tg; and these effects are non-linearly related to the initial melt temperatures, and fluctuated in a certain range. However, the changes of the average atomic energy of the systems are still linearly related with the initial melt temperatures, namely, the higher the initial melt temperature is, the more stable the amorphous structure is and the stronger the glass forming ability will be.展开更多
Departing from an analytical phase transformation model, a new analytical approach to deduce transformed fraction for non-isothermal phase transformation was developed. In the new approach, the effect of the initial t...Departing from an analytical phase transformation model, a new analytical approach to deduce transformed fraction for non-isothermal phase transformation was developed. In the new approach, the effect of the initial transformation temperature and the accurate "temperature integral" approximations are incorporated to obtain an extended analytical model. Numerical approach demonstrated that the extended analytical model prediction for transformed fraction and transformation rate is in good agreement with the exact numerical calculation. The new model can describe more precisely the kinetic behavior than the original analytical model, especially for transformation with relatively high initial transformation temperature. The kinetic parameters obtained from the new model are more accurate and reasonable than those from the original analytical model.展开更多
文摘Objectives:In the sphere of occupational intensity,nursing stands recognized for its inherently demanding nature,marked by a rapid succession of tasks.Our primary aim was to assess the level of job intensity within nursing by analyzing the frequency and duration of activities performed by nurses,instances of task overlap,and the distribution of break times within a primary healthcare center.Methods:This study was conducted using a descriptive working method.Nursing activities were recorded with the observation of six nurses,each monitored for 37.5 h.We used the Maribor System for measuring Quantity in Nursing Care in Primary Health Care Settings to measure the nursing care activities about direct patient care,indirect patient care,and other unproductive aspects through direct non-participant observations.Results:About 41.5%(n=1,640)of all nursing activities involving direct contact with patients,about 38.2%(n=1,508)was indirect patient care,where a large amount worked with paper files(n=666,16.9%).In addition,about 15.0%were other nursing activities(mostly computer work),and just 5.3%(n=210)of tasks were unproductive.The observational findings indicate a pronounced level of work intensity experienced by nurses in primary health clinics.Significantly,nurses were predominantly engaged in direct patient care tasks,often managing multiple activities simultaneously.Their transitions between tasks occurred approximately every 3 min,frequently without adequate intervals for breaks.Conclusions:This study highlights the need to shift nurses’focus from a task-centric approach to one centered on patient care.The prevailing emphasis on tasks may contribute to enduring fatigue and professional dissatisfaction.Consequently,there is an urgent need to redefine the scope of a nurse’s role and implement a comprehensive computer information system as an integral part of this redefined approach.
基金Projects(511040365137406651304047)supported by the National Natural Science Foundation of China
文摘The catalytic performance on jarosite process of jarosite seeds via biosynthesis and chemical processes were studied, respectively. The SEM and XRD results showed that biosynthetic jarosite seeds (BIO seeds) had smooth surface and mainly consisted of potassium jarosite. The chemical synthesis jarosite seeds (CHM seeds) had a loose cauliflower-like surface and mainly consisted of hydronium jarosite. The catalytic performance of BIO seeds was better than that of CHM seeds on the formation of final jarosite product. The induction time can be shortened to 20 min, the reaction temperature can be reduced to only 75 ℃, and the initial reaction speed was enhanced obviously, up to 3.933%/min. The crystallinity of final jarosite product using BIO seeds can achieve 97.22%, while it was only 12.89% without seeds. This indicates that the precipitation process of jarosite is more complete with BIO seeds.
基金Supported by National Natural Science Foundation of China(31171082)Natural Science Foundation of Anhui Province(070413138)the Key Research Foundation of Anhui Province Education Department(KJ2009A167)
文摘Psychophysical experiments on human and animal subjects have proven that aged individuals show significantly reduced visual contrast sensitivity compared with young adults.To uncover the possible neural mechanisms,we used extracellular single-unit recording techniques to examine the response of V1(primary visual cortex) neurons as a function of visual stimulus contrast in both old and young adult cats(Felis catus).The mean contrast sensitivity of V1 neurons to visual stimuli in old cats decreased significantly relative to young adult cats,consistent with findings reported in old primates.These results indicate that aging can affect contrast sensitivity of visual cortical cells in both primate and non-primate mammalian animals,and might contribute to the reduction of perceptual visual contrast sensitivity in aged individuals.Further,V1 cells of old cats exhibited increased responsiveness,decreased signal-to-noise ratio,and enlarged receptive field(RF) size compared with that of young adult cats,which indicated that decreased contrast sensitivity of V1 neurons accompanied a reduction of intracortical inhibition during senescence.
基金sponsored by the National Natural Science Foundation of China (No. 41074075)
文摘Serious stretch appears in shallow long offsset signals after NMO correction. In this article we study the generation mechanism of NMO stretch, demonstrate that the conventional travel time equation cannot accurately describe the travel time of the samples within the same reflection wavelet. As a result, conventional NMO inversion based on the travel time of the wavelet's central point occurs with errors. In this article, a travel time equation for the samples within the same wavelet is reconstructed through our theoretical derivation (the shifted first arrival point travel time equation), a new NMO inversion method based on the wavelet's first arrival point is proposed. While dealing with synthetic data, the semblance coefficient algorithm equation is modified so that wavelet first arrival points can be extracted. After that, NMO inversion based on the new velocity analysis is adopted on shot offset records. The precision of the results is significantly improved compared with the traditional method. Finally, the block move NMO correction based on the first arrival points travel times is adopted on long offset records and non-stretched results are achieved, which verify the proposed new equation.
基金Projects(50831003,51071065,51101022,51102090) supported by the National Natural Science Foundation of China
文摘The non-linear effects of different initial melt temperatures on the microstructure evolution during the solidification process of liquid Mg7Zn3 alloys were investigated by molecular dynamics simulation, The microstructure transformation mechanisms were analyzed by several methods. The system was found to be solidified into amorphous structures from different initial melt temperatures at the same cooling rate of 1×10^12 K/s, and the 1551 bond-type and the icosahedron basic cluster (12 0 12 0 ) played a key role in the microstructure transition. Different initial melt temperatures had significant effects on the final microstructures. These effects only can be clearly observed below the glass transition temperature Tg; and these effects are non-linearly related to the initial melt temperatures, and fluctuated in a certain range. However, the changes of the average atomic energy of the systems are still linearly related with the initial melt temperatures, namely, the higher the initial melt temperature is, the more stable the amorphous structure is and the stronger the glass forming ability will be.
基金Projects (09-QZ-2008, 24-TZ-2009) supported by the Free Research Fund of State Key Laboratory of Solidification Processing, ChinaProject (B08040) supported by the Program of Introducing Talents of Discipline to Universities, China+3 种基金Projects (51071127, 51134011) supported by the National Natural Science Foundation of ChinaProject (JC200801) supported by the Fundamental Research Fund of Northwestern Polytechnical University, ChinaProject (51125002) supported by the National Science Foundation for Distinguished Young Scholars, ChinaProject (2011CB610403) supported by the National Basic Research Program of China
文摘Departing from an analytical phase transformation model, a new analytical approach to deduce transformed fraction for non-isothermal phase transformation was developed. In the new approach, the effect of the initial transformation temperature and the accurate "temperature integral" approximations are incorporated to obtain an extended analytical model. Numerical approach demonstrated that the extended analytical model prediction for transformed fraction and transformation rate is in good agreement with the exact numerical calculation. The new model can describe more precisely the kinetic behavior than the original analytical model, especially for transformation with relatively high initial transformation temperature. The kinetic parameters obtained from the new model are more accurate and reasonable than those from the original analytical model.