Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC...Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC semiconductor device,an instrumentation amplifier(IA),two resistors,and a diode for disconnection detection.Based on the basic circuit,a multi-channel interface circuit was also implemented.The CJC was implemented using compensation semiconductor and IA,and disconnection detection was detected by using two resistors and a diode so that IA input voltage became-0.42 V.As a result of the experiment using R-type TC,the error of the designed circuit was reduced from 0.14 mV to 3μV after CJC in the temperature range of 0°C to 1400°C.In addition,it was confirmed that the output voltage of IA was saturated from 88 mV to-14.2 V when TC was disconnected from normal.The output voltage of the designed circuit was 0 V to 10 V in the temperature range of 0°C to 1400°C.The results of the 4-channel interface experiment using R-type TC were almost identical to the CJC and disconnection detection results for each channel.The implemented multi-channel interface has a feature that can be applied equally to E,J,K,T,R,and S-type TCs by changing the terminals of CJC semiconductor devices and adjusting the IA gain.展开更多
With the rapid development of our country’s economy,education has gradually become the focus of social attention.The problem of unbalanced distribution of urban and rural educational resources has become increasingly...With the rapid development of our country’s economy,education has gradually become the focus of social attention.The problem of unbalanced distribution of urban and rural educational resources has become increasingly prominent,urban educational resources are relatively rich,while rural educational resources are relatively scarce,and the balanced development of urban and rural compulsory education has become an urgent task.This paper mainly investigates and studies the distribution of urban and rural educational resources,discusses the unbalanced distribution of urban and rural educational resources and analyzes the reasons,and puts forward a series of corresponding solutions to promote the balanced development of urban and rural compulsory education.展开更多
Background: Cholangiocarcinoma (CCA) is from cholangiocytes, and therefore bile is a potentially rich source of biomarkers for CCA. The aim of the study was to identify and validate microRNAs (miRNAs) in bile samples ...Background: Cholangiocarcinoma (CCA) is from cholangiocytes, and therefore bile is a potentially rich source of biomarkers for CCA. The aim of the study was to identify and validate microRNAs (miRNAs) in bile samples that are differentially expressed between benign biliary disease (BBD) and CCA. Methods: Bile samples from 106 patients with obstructive biliary disease were allocated consecutively to a discovery set (10 patients with BBD and 11 with CCA) and then a validation set (48 patients with BBD and 37 with CCA). An miRNA microarray platform was used to screen 1209 miRNAs in the discovery set. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to validate the pro ling results in the discovery and validation sets. In addition, the levels of carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) were determined from patient serum samples. Results: Microarray pro ling showed that miR-30d-5p and miR-92a-3p were signi cantly upregulated in bile from the CCA group compared with those from the BBD group. qRT-PCR results indicated that the expression levels of miR-30d-5p and of miR-92a-3p were signi cantly upregulated in the CCA group compared to the BBD group, validating the miRNA microarray results. Pathway analysis suggested that putative target genes of miR-30d-5p and of miR-92a-3p were involved in CCA-associated signalling path- ways, such as Hippo, Wnt, p53, MAPK, and EGFR. Receiver operating curve analysis revealed that the areas under the curve for bile miR-30d-5p, miR-92a-3p, serum CA19-9, and CEA were 0.730, 0.652, 0.675, and 0.603, respectively, and bile miR-30d-5p showed the best diagnostic performance with a sensitivity of 81.1% and a speci city of 60.5%. Conclusions: The levels of extracellular miR-30d-5p and miR-92a-3p in bile were signi cantly higher in patients with CCA than those in patients with BBD. Bile-derived circulating extracellular miR-30d-5p and miR-92a-3p are potential biomarkers for discriminating CCA from BBD.展开更多
This study aimed to investigate the effects of exercise-induced muscle fatigue in the unaffected knee joint on postural control and kinematic changes in stroke patients. Forty participants(20 stroke patients, 20 age-...This study aimed to investigate the effects of exercise-induced muscle fatigue in the unaffected knee joint on postural control and kinematic changes in stroke patients. Forty participants(20 stroke patients, 20 age-matched healthy participants) were recruited. To induce fatigue, maximum voluntary isometric contractions were performed in the unaffected knee joint in a Leg Extension Rehab exercise machine using the pneumatic resistance. We measured static and dynamic balance and lower-limb kinematics during gait. Changes in postural control parameters anteroposterior sway speed and total center of pressure distance differed significantly between the stroke and control groups. In addition, changes in gait kinematic parameters knee and ankle angles of initial contact differed significantly between stroke(paretic and non-paretic) and control groups. Muscle fatigue in the unaffected knee and ankle impaired postural control and debilitates kinematic movement of ipsilateral and contralateral lower limbs, and may place the fatigued stroke patients at greater risk for falls.展开更多
Transcranial direct current stimulation (tDCS), an emerging technique for non-invasive brain stimulation, is increasingly used to induce changes in cortical excitability and modulate motor behavior, especially for u...Transcranial direct current stimulation (tDCS), an emerging technique for non-invasive brain stimulation, is increasingly used to induce changes in cortical excitability and modulate motor behavior, especially for upper limbs. The purpose of this study was to investigate the effects of tDCS of the primary motor cortex on visuomotor coordination based on three levels of task difficulty in healthy subjects. Thirty-eight healthy participants underwent real tDCS or sham tDCS. Using a single-blind, sham-controlled crossover design, tDCS was applied to the primary motor cortex. For real tDCS conditions, tDCS intensity was 1 mA while stimulation was applied for 15 minutes. For the sham tDCS, electrodes were placed in the same position, but the stimu- lator was turned off after 5 seconds. Visuomotor tracking task, consisting of three levels (levels 1, 2, 3) of difficulty with higher level indicating greater difficulty, was performed before and after tDCS application. At level 2, real tDCS of the primary motor cortex improved the accurate index compared to the sham tDCS. However, at levels 1 and 3, the accurate index was not significantly increased after real tDCS compared to the sham tDCS. These findings suggest that tasks of mod- erate difficulty may improve visuomotor coordination in healthy subjects when tDCS is applied compared with easier or more difficult tasks.展开更多
AIM:To evaluate the impact of surgical volume on nationwide hospital mortality after pancreaticoduodenectomy(PD) for periampullary tumors in South Korea.METHODS:Periampullary cancer patients who underwent PD between 2...AIM:To evaluate the impact of surgical volume on nationwide hospital mortality after pancreaticoduodenectomy(PD) for periampullary tumors in South Korea.METHODS:Periampullary cancer patients who underwent PD between 2005 and 2008 were analyzed from the database of the Health Insurance Review and Assessment Service of South Korea.A total of 126 hospitals were divided into 5 categories,each similar in terms of surgical volume for each category.We used hospital mortality as a quality indicator,which was defined as death during the hospital stay for PD,and calculated adjusted mortality through multivariate logistic models using several confounder variables.RESULTS:A total of eligible 4975 patients were enrolled in this study.Average annual surgical volume of hospitals was markedly varied,ranging from 215 PDs in the very-high-volume hospital to < 10 PDs in the verylow-volume hospitals.Admission route,type of medical security,and type of operation were significantly different by surgical volume.The overall hospital mortality was 2.1% and the observed hospital mortality by surgical volume showed statistical difference.Surgical volume,age,and type of operation were independent risk factors for hospital death,and adjusted hospital mortality showed a similar difference between hospitals with observed mortality.The result of the HosmerLemeshow test was 5.76(P = 0.674),indicating an acceptable appropriateness of our regression model.CONCLUSION:The higher-volume hospitals showed lower hospital mortality than the lower-volume hospitals after PD in South Korea,which were clarified through the nationwide database.展开更多
Oxycodone hydrochloride is a semi-synthetic opioid agonist that provides very effective relief for moderate to severe pain in cancer and post-operative patients. Controlled release oxycodone formulations have been stu...Oxycodone hydrochloride is a semi-synthetic opioid agonist that provides very effective relief for moderate to severe pain in cancer and post-operative patients. Controlled release oxycodone formulations have been studied to enhance the therapeutic effect by providing constant release over the whole dosing interval and improve patient’s convenience by reducing the frequency of administration as well.展开更多
Recently the importance of intellectual property has been increased. There has been various ways of research on analy- sis of companies, forecast of technology and so on through patents and many investments of money a...Recently the importance of intellectual property has been increased. There has been various ways of research on analy- sis of companies, forecast of technology and so on through patents and many investments of money and time. Unlike traditional method of patent analysis such as company analysis, forecasting technologies, this research is to suggest the ways to forecast registration and rejection of patents which help minimize the efforts to register patents. To do so, in- formation such as inventors, applicants, application date, and IPC codes were extracted to be used as input variables for analyzing Bayesian network. Especially, among various forms of Bayesian network, we used Tree Augmented NBN (TAN) to forecast registration and rejection of patent. This is because, TAN was assumed to have dependence between variables. As a result of this Bayesian network, it was shown that there are nearly more than 80% of accuracy to fore- cast registration and rejection of patents. Therefore, we expect the minimization of time and cost of registration by forecasting registration and rejection of R&D patent through this research.展开更多
This study investigated the effect of transcranial direct current stimulation(t DCS) polarity depending on lateralized function of task property in normal individuals performing visuomotor and simple repetitive task...This study investigated the effect of transcranial direct current stimulation(t DCS) polarity depending on lateralized function of task property in normal individuals performing visuomotor and simple repetitive tasks. Thirty healthy participants with no neurological disorders were recruited to participate in this study. Participants were randomly allocated into active or control condition. For the active condition, t DCS intensity was 2 m A with stimulation applied for 15 minutes to the right hemisphere(t DCS condition). For the sham control, electrodes were placed in the same position, but the stimulator was turned off after 30 seconds(sham condition). The tapping and tracking task tests were performed before and after for both conditions. Univariate analysis revealed significant difference only in the tracking task. For direct comparison of both tasks within each group, the tracking task had significantly higher Z score than the tapping task in the t DCS group(P 〈 0.05). Thus, our study indicates that stimulation of the right hemisphere using t DCS can effectively improve visuomotor(tracking) task over simple repetitive(tapping) task.展开更多
High-voltage nickel-rich layered cathodes possess the requisite,such as excellent discharge capacity and high energy density,to realize lithium batteries with higher energy density.However,such materials suffer from s...High-voltage nickel-rich layered cathodes possess the requisite,such as excellent discharge capacity and high energy density,to realize lithium batteries with higher energy density.However,such materials suffer from structural and interfacial instability at high voltages(>4.3 V).To reinforce the stability of these cathode materials at elevated voltages,lithium borate salts are investigated as electrolyte additives to generate a superior cathode-electrolyte interphase.Specifically,the use of lithium bis(oxalato)borate(LiBOB)leads to an enhanced cycling stability with a capacity retention of 81.7%.Importantly,almost no voltage hysteresis is detected after 200 cycles at 1C.This outstanding electrochemical performance is attributed to an enhanced structural and interfacial stability,which is attained by suppressing the generation of micro-cracks and the superficial structural degradation upon cycling.The improved stability stems from the formation of a fortified borate-containing interphase which protects the highly reactive cathode from parasitic reactions with the electrolyte.Finally,the decomposition process of LiBOB and the possible adsorption routes to the cathode surface are deduced and elucidated.展开更多
Brown adipose tissue (BAT) plays a fundamental role in maintaining body temperature by producing heat. BAT that had been know to exist only in mammals and the human neonate has received great attention for the treat...Brown adipose tissue (BAT) plays a fundamental role in maintaining body temperature by producing heat. BAT that had been know to exist only in mammals and the human neonate has received great attention for the treatment of obesity and diabetes due to its important function in energy metabolism, ever since it is recently reported that human adults have functional BAT. In addition, beige adipocytes, brown adipocytes in white adipose tissue (WAT), have also been shown to take part in whole body metabolism. Multiple lines of evidence demonstrated that transplantation or activation of BAT or/and beige adipocytes reversed obesity and improved insulin sensitivity. Furthermore, many genes involved in BAT activation and/or the recruitment of beige cells have been found, thereby providing new promising strategies for future clinical application of BAT activation to treat obesity and metabolic diseases. This review focuses on recent advances of BAT function in the metabolic aspect and the relationship between BAT and cancer cachexia, a pathological process accompanied with decreased body weight and increased energy expenditure in cancer patients. The underlying possible mechanisms to reduce BAT mass and its activity in the elderly are also discussed.展开更多
The single crystal of this compound has been grown from melt by using a conventional Czochralski technique. The temperature dependent luminescence spectra were measured using a 265 nm laser as an exciting source in th...The single crystal of this compound has been grown from melt by using a conventional Czochralski technique. The temperature dependent luminescence spectra were measured using a 265 nm laser as an exciting source in the range of 10-300 K. The scintillation decay time profile was measured and found to have three components. The influence of the trap centers on the luminescence properties was studied by means of thermoluminescence(TL) glow peak analysis. Low temperature TL glow peaks were measured in the temperature range of 10-300 K at the heating rate of 0.1 K/s for X-ray irradiated sample. The TL glow peak consists of two dominant peaks at 88 and 109 K. Several glow peaks with a complex nature causes the decrease in the light yield at temperatures below 250 K, and along with long scintillation decay components were observed. The trap parameters such as activation energy(E), frequency factor(s)and order of kinetics(b) were calculated using various standard methods such as peak shape(PS),variable heating rate(VHR), initial rise(IR) and computerized glow curve deconvolution(CGCD).展开更多
Understanding the stress-induced phenomena is essential for improving the long-term application of flexible solar cells to non-flat surfaces.Here,we investigated the electronic band structure and carrier transport mec...Understanding the stress-induced phenomena is essential for improving the long-term application of flexible solar cells to non-flat surfaces.Here,we investigated the electronic band structure and carrier transport mechanism of Cu2ZnSn(S,Se)4(CZTSSe)photovoltaic devices under mechanical stress.Highly efficient flexible CZTSSe devices were fabricated controlling the Na incorporation.The electronic structure of CZTSSe was deformed with stress as the band gap,valence band edge,and work function changed.Electrical properties of the bent CZTSSe surface were probed by Kelvin probe force microscopy and the CZTSSe with Na showed less degraded carrier transport compared to the CZTSSe without Na.The local open-circuit voltage(VOC)on the bent CZTSSe surface decreased due to limited carrier excitation.The reduction of local VOC occurred larger with convex bending than in concave bending,which is consistent with the degradation of device parameters.This study paves the way for understanding the stress-induced optoelectronic changes in flexible photovoltaic devices.展开更多
According to a statistic,approximately 6 trillion cigarettes are smoked each year all over the world,which produces approximately 1.2 million tons of discarded cigarette butts.The discarded cigarette filters are non-b...According to a statistic,approximately 6 trillion cigarettes are smoked each year all over the world,which produces approximately 1.2 million tons of discarded cigarette butts.The discarded cigarette filters are non-biodegradable,thus they produce a mass of waste disposal and cause environmental pollution is-sue.For the purpose of transforming waste into wealth and reducing environmental pollution,nitrogen and sulfur co-doped carbon nanofiber/carbon black(N,S-CNF/CB)composite derived from the discarded cigarette filters is employed to modify glass fiber(GF)separator for the first time in this study.N,S-CNF improves binding ability towards sodium polysulfides(SPSs)by chemisorption.Non-polar CB limits the dissolution of SPSs in the liquid electrolyte by physisorption.The experiment and density functional theory calculation results indicate that a RT-Na/S battery with a N,S-CNF/CB+GF separator exhibits good cycling stability and rate performance.After 100 cycles at a low current rate of 0.1 C,a RT-Na/S battery with a sulfur mass fraction of 71%delivers a discharge capacity of 703 mAh g^(−1).In addition,at a high current rate of 0.5 C,a discharge capacity of 527 mAh g^(−1) is still maintained after 900 cycles with a very low capacity fading rate of 0.035%per cycle.展开更多
Objective:SC-E3 is a polyherbal formula that contains five medicinal herbs used frequently in traditional herbal medicine.In our previous study,we demonstrated the antioxidant and anti-inflammatory effects of SC-E3.Th...Objective:SC-E3 is a polyherbal formula that contains five medicinal herbs used frequently in traditional herbal medicine.In our previous study,we demonstrated the antioxidant and anti-inflammatory effects of SC-E3.The present study examined the effects of SC-E3 in a mouse model of type-II collagen-induced arthritis(CIA).Methods:In vivo,male DBA/1 J mice were immunized by intradermal injection of bovine type-II collagen and complete or incomplete Freund’s adjuvant,to induce arthritis.SC-E3 was orally administered daily for 23 days.In vitro,bone marrow-derived macrophages(BMMs)were treated with macrophage colony-stimulating factor(M-CSF)and receptor activator of nuclear factor-j B ligand(RANKL)in the absence or presence of SC-E3.Results:Administrations of SC-E3 were found to have anti-arthritic effects in the joints of CIA mice,as evidenced by reduced paw swelling,bone erosion and deformation,inflammatory cell infiltration,and inflammation in synovial membrane.SC-E3 also reduced serum levels of tumor necrosis factor-a,interleukin-1 b,aspartate aminotransferase and alanine aminotransferase.Furthermore,tartrateresistant acid phosphatase-positive osteoclast numbers in the joints were significantly lower in SC-E3-treated CIA mice than in CIA mice.In addition,the differentiations of BMMs to multinucleated osteoclasts induced by M-CSF and RANKL stimulation were dose-dependently reduced by SC-E3.Conclusion:These results suggest that SC-E3 possesses substantial anti-arthritic activity because it inhibits pro-inflammatory cytokines and osteoclastogenesis,and that SC-E3 has potential therapeutic use for the treatment of rheumatoid arthritis.展开更多
文摘Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC semiconductor device,an instrumentation amplifier(IA),two resistors,and a diode for disconnection detection.Based on the basic circuit,a multi-channel interface circuit was also implemented.The CJC was implemented using compensation semiconductor and IA,and disconnection detection was detected by using two resistors and a diode so that IA input voltage became-0.42 V.As a result of the experiment using R-type TC,the error of the designed circuit was reduced from 0.14 mV to 3μV after CJC in the temperature range of 0°C to 1400°C.In addition,it was confirmed that the output voltage of IA was saturated from 88 mV to-14.2 V when TC was disconnected from normal.The output voltage of the designed circuit was 0 V to 10 V in the temperature range of 0°C to 1400°C.The results of the 4-channel interface experiment using R-type TC were almost identical to the CJC and disconnection detection results for each channel.The implemented multi-channel interface has a feature that can be applied equally to E,J,K,T,R,and S-type TCs by changing the terminals of CJC semiconductor devices and adjusting the IA gain.
文摘With the rapid development of our country’s economy,education has gradually become the focus of social attention.The problem of unbalanced distribution of urban and rural educational resources has become increasingly prominent,urban educational resources are relatively rich,while rural educational resources are relatively scarce,and the balanced development of urban and rural compulsory education has become an urgent task.This paper mainly investigates and studies the distribution of urban and rural educational resources,discusses the unbalanced distribution of urban and rural educational resources and analyzes the reasons,and puts forward a series of corresponding solutions to promote the balanced development of urban and rural compulsory education.
基金supported by grants from a Basic Science Re-search Program through the National Research Foundation of Ko-rea(NRF)funded by the Ministry of Education,Science and Tech-nology(2017R1A5A2015541 and 2019R1A2C1007401)’’+1 种基金supported by a grant from the National R&D Program for Cancer Control,Ministry of Health and Welfare,Republic of Ko-rea(1120330)a National Research Foundation of Korea grant funded by the Korea government(NRF-2013R 1A 1A 2063994)
文摘Background: Cholangiocarcinoma (CCA) is from cholangiocytes, and therefore bile is a potentially rich source of biomarkers for CCA. The aim of the study was to identify and validate microRNAs (miRNAs) in bile samples that are differentially expressed between benign biliary disease (BBD) and CCA. Methods: Bile samples from 106 patients with obstructive biliary disease were allocated consecutively to a discovery set (10 patients with BBD and 11 with CCA) and then a validation set (48 patients with BBD and 37 with CCA). An miRNA microarray platform was used to screen 1209 miRNAs in the discovery set. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to validate the pro ling results in the discovery and validation sets. In addition, the levels of carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) were determined from patient serum samples. Results: Microarray pro ling showed that miR-30d-5p and miR-92a-3p were signi cantly upregulated in bile from the CCA group compared with those from the BBD group. qRT-PCR results indicated that the expression levels of miR-30d-5p and of miR-92a-3p were signi cantly upregulated in the CCA group compared to the BBD group, validating the miRNA microarray results. Pathway analysis suggested that putative target genes of miR-30d-5p and of miR-92a-3p were involved in CCA-associated signalling path- ways, such as Hippo, Wnt, p53, MAPK, and EGFR. Receiver operating curve analysis revealed that the areas under the curve for bile miR-30d-5p, miR-92a-3p, serum CA19-9, and CEA were 0.730, 0.652, 0.675, and 0.603, respectively, and bile miR-30d-5p showed the best diagnostic performance with a sensitivity of 81.1% and a speci city of 60.5%. Conclusions: The levels of extracellular miR-30d-5p and miR-92a-3p in bile were signi cantly higher in patients with CCA than those in patients with BBD. Bile-derived circulating extracellular miR-30d-5p and miR-92a-3p are potential biomarkers for discriminating CCA from BBD.
文摘This study aimed to investigate the effects of exercise-induced muscle fatigue in the unaffected knee joint on postural control and kinematic changes in stroke patients. Forty participants(20 stroke patients, 20 age-matched healthy participants) were recruited. To induce fatigue, maximum voluntary isometric contractions were performed in the unaffected knee joint in a Leg Extension Rehab exercise machine using the pneumatic resistance. We measured static and dynamic balance and lower-limb kinematics during gait. Changes in postural control parameters anteroposterior sway speed and total center of pressure distance differed significantly between the stroke and control groups. In addition, changes in gait kinematic parameters knee and ankle angles of initial contact differed significantly between stroke(paretic and non-paretic) and control groups. Muscle fatigue in the unaffected knee and ankle impaired postural control and debilitates kinematic movement of ipsilateral and contralateral lower limbs, and may place the fatigued stroke patients at greater risk for falls.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT&Future Planning,No.2012R1A1B4003477
文摘Transcranial direct current stimulation (tDCS), an emerging technique for non-invasive brain stimulation, is increasingly used to induce changes in cortical excitability and modulate motor behavior, especially for upper limbs. The purpose of this study was to investigate the effects of tDCS of the primary motor cortex on visuomotor coordination based on three levels of task difficulty in healthy subjects. Thirty-eight healthy participants underwent real tDCS or sham tDCS. Using a single-blind, sham-controlled crossover design, tDCS was applied to the primary motor cortex. For real tDCS conditions, tDCS intensity was 1 mA while stimulation was applied for 15 minutes. For the sham tDCS, electrodes were placed in the same position, but the stimu- lator was turned off after 5 seconds. Visuomotor tracking task, consisting of three levels (levels 1, 2, 3) of difficulty with higher level indicating greater difficulty, was performed before and after tDCS application. At level 2, real tDCS of the primary motor cortex improved the accurate index compared to the sham tDCS. However, at levels 1 and 3, the accurate index was not significantly increased after real tDCS compared to the sham tDCS. These findings suggest that tasks of mod- erate difficulty may improve visuomotor coordination in healthy subjects when tDCS is applied compared with easier or more difficult tasks.
文摘AIM:To evaluate the impact of surgical volume on nationwide hospital mortality after pancreaticoduodenectomy(PD) for periampullary tumors in South Korea.METHODS:Periampullary cancer patients who underwent PD between 2005 and 2008 were analyzed from the database of the Health Insurance Review and Assessment Service of South Korea.A total of 126 hospitals were divided into 5 categories,each similar in terms of surgical volume for each category.We used hospital mortality as a quality indicator,which was defined as death during the hospital stay for PD,and calculated adjusted mortality through multivariate logistic models using several confounder variables.RESULTS:A total of eligible 4975 patients were enrolled in this study.Average annual surgical volume of hospitals was markedly varied,ranging from 215 PDs in the very-high-volume hospital to < 10 PDs in the verylow-volume hospitals.Admission route,type of medical security,and type of operation were significantly different by surgical volume.The overall hospital mortality was 2.1% and the observed hospital mortality by surgical volume showed statistical difference.Surgical volume,age,and type of operation were independent risk factors for hospital death,and adjusted hospital mortality showed a similar difference between hospitals with observed mortality.The result of the HosmerLemeshow test was 5.76(P = 0.674),indicating an acceptable appropriateness of our regression model.CONCLUSION:The higher-volume hospitals showed lower hospital mortality than the lower-volume hospitals after PD in South Korea,which were clarified through the nationwide database.
文摘Oxycodone hydrochloride is a semi-synthetic opioid agonist that provides very effective relief for moderate to severe pain in cancer and post-operative patients. Controlled release oxycodone formulations have been studied to enhance the therapeutic effect by providing constant release over the whole dosing interval and improve patient’s convenience by reducing the frequency of administration as well.
文摘Recently the importance of intellectual property has been increased. There has been various ways of research on analy- sis of companies, forecast of technology and so on through patents and many investments of money and time. Unlike traditional method of patent analysis such as company analysis, forecasting technologies, this research is to suggest the ways to forecast registration and rejection of patents which help minimize the efforts to register patents. To do so, in- formation such as inventors, applicants, application date, and IPC codes were extracted to be used as input variables for analyzing Bayesian network. Especially, among various forms of Bayesian network, we used Tree Augmented NBN (TAN) to forecast registration and rejection of patent. This is because, TAN was assumed to have dependence between variables. As a result of this Bayesian network, it was shown that there are nearly more than 80% of accuracy to fore- cast registration and rejection of patents. Therefore, we expect the minimization of time and cost of registration by forecasting registration and rejection of R&D patent through this research.
文摘This study investigated the effect of transcranial direct current stimulation(t DCS) polarity depending on lateralized function of task property in normal individuals performing visuomotor and simple repetitive tasks. Thirty healthy participants with no neurological disorders were recruited to participate in this study. Participants were randomly allocated into active or control condition. For the active condition, t DCS intensity was 2 m A with stimulation applied for 15 minutes to the right hemisphere(t DCS condition). For the sham control, electrodes were placed in the same position, but the stimulator was turned off after 30 seconds(sham condition). The tapping and tracking task tests were performed before and after for both conditions. Univariate analysis revealed significant difference only in the tracking task. For direct comparison of both tasks within each group, the tracking task had significantly higher Z score than the tapping task in the t DCS group(P 〈 0.05). Thus, our study indicates that stimulation of the right hemisphere using t DCS can effectively improve visuomotor(tracking) task over simple repetitive(tapping) task.
基金the financial support from the Chinese Scholarship Council(CSC).Moreover,the authors would like to acknowledge the financial support from the Helmholtz Association and the European Commission in the frame of the SiGNE project(875557)Jae-Kwang Kim acknowledges the support from the Advancement of Technology(KIAT)and the National Research Foundation of Korea(NRF)grant funded by the Korea Government(P0011933 and 2021R1A4A2001687).
文摘High-voltage nickel-rich layered cathodes possess the requisite,such as excellent discharge capacity and high energy density,to realize lithium batteries with higher energy density.However,such materials suffer from structural and interfacial instability at high voltages(>4.3 V).To reinforce the stability of these cathode materials at elevated voltages,lithium borate salts are investigated as electrolyte additives to generate a superior cathode-electrolyte interphase.Specifically,the use of lithium bis(oxalato)borate(LiBOB)leads to an enhanced cycling stability with a capacity retention of 81.7%.Importantly,almost no voltage hysteresis is detected after 200 cycles at 1C.This outstanding electrochemical performance is attributed to an enhanced structural and interfacial stability,which is attained by suppressing the generation of micro-cracks and the superficial structural degradation upon cycling.The improved stability stems from the formation of a fortified borate-containing interphase which protects the highly reactive cathode from parasitic reactions with the electrolyte.Finally,the decomposition process of LiBOB and the possible adsorption routes to the cathode surface are deduced and elucidated.
文摘Brown adipose tissue (BAT) plays a fundamental role in maintaining body temperature by producing heat. BAT that had been know to exist only in mammals and the human neonate has received great attention for the treatment of obesity and diabetes due to its important function in energy metabolism, ever since it is recently reported that human adults have functional BAT. In addition, beige adipocytes, brown adipocytes in white adipose tissue (WAT), have also been shown to take part in whole body metabolism. Multiple lines of evidence demonstrated that transplantation or activation of BAT or/and beige adipocytes reversed obesity and improved insulin sensitivity. Furthermore, many genes involved in BAT activation and/or the recruitment of beige cells have been found, thereby providing new promising strategies for future clinical application of BAT activation to treat obesity and metabolic diseases. This review focuses on recent advances of BAT function in the metabolic aspect and the relationship between BAT and cancer cachexia, a pathological process accompanied with decreased body weight and increased energy expenditure in cancer patients. The underlying possible mechanisms to reduce BAT mass and its activity in the elderly are also discussed.
基金Project supported by the National Research Foundation of Korea(NRF) funded by the Ministry of Science and Technology,Korea(MEST)(NRF2017M2A8A4018678)
文摘The single crystal of this compound has been grown from melt by using a conventional Czochralski technique. The temperature dependent luminescence spectra were measured using a 265 nm laser as an exciting source in the range of 10-300 K. The scintillation decay time profile was measured and found to have three components. The influence of the trap centers on the luminescence properties was studied by means of thermoluminescence(TL) glow peak analysis. Low temperature TL glow peaks were measured in the temperature range of 10-300 K at the heating rate of 0.1 K/s for X-ray irradiated sample. The TL glow peak consists of two dominant peaks at 88 and 109 K. Several glow peaks with a complex nature causes the decrease in the light yield at temperatures below 250 K, and along with long scintillation decay components were observed. The trap parameters such as activation energy(E), frequency factor(s)and order of kinetics(b) were calculated using various standard methods such as peak shape(PS),variable heating rate(VHR), initial rise(IR) and computerized glow curve deconvolution(CGCD).
基金supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF)funded by the Ministry of Education (NRF-2018R1A6A1A03025340)Ministry of Science,Technology,ICT,and Future Planning (NRF-2021R1A2B5B02001961)+1 种基金supported by the program of Phased development of carbon neutral technologies through the National Research Foundation of Korea (NRF) funded by the Ministry of Science,ICT (NRF2022M3J1A1064229)supported by the DGIST R&D programs of the Ministry of Science and ICT (22-CoE-ET-01).
文摘Understanding the stress-induced phenomena is essential for improving the long-term application of flexible solar cells to non-flat surfaces.Here,we investigated the electronic band structure and carrier transport mechanism of Cu2ZnSn(S,Se)4(CZTSSe)photovoltaic devices under mechanical stress.Highly efficient flexible CZTSSe devices were fabricated controlling the Na incorporation.The electronic structure of CZTSSe was deformed with stress as the band gap,valence band edge,and work function changed.Electrical properties of the bent CZTSSe surface were probed by Kelvin probe force microscopy and the CZTSSe with Na showed less degraded carrier transport compared to the CZTSSe without Na.The local open-circuit voltage(VOC)on the bent CZTSSe surface decreased due to limited carrier excitation.The reduction of local VOC occurred larger with convex bending than in concave bending,which is consistent with the degradation of device parameters.This study paves the way for understanding the stress-induced optoelectronic changes in flexible photovoltaic devices.
基金supported by the National Natural Science Foundation of China(Nos.51631004 and 52130101)the Basic Construction Fund in Jilin Province Budget for 2019(No.2019C042-8).
文摘According to a statistic,approximately 6 trillion cigarettes are smoked each year all over the world,which produces approximately 1.2 million tons of discarded cigarette butts.The discarded cigarette filters are non-biodegradable,thus they produce a mass of waste disposal and cause environmental pollution is-sue.For the purpose of transforming waste into wealth and reducing environmental pollution,nitrogen and sulfur co-doped carbon nanofiber/carbon black(N,S-CNF/CB)composite derived from the discarded cigarette filters is employed to modify glass fiber(GF)separator for the first time in this study.N,S-CNF improves binding ability towards sodium polysulfides(SPSs)by chemisorption.Non-polar CB limits the dissolution of SPSs in the liquid electrolyte by physisorption.The experiment and density functional theory calculation results indicate that a RT-Na/S battery with a N,S-CNF/CB+GF separator exhibits good cycling stability and rate performance.After 100 cycles at a low current rate of 0.1 C,a RT-Na/S battery with a sulfur mass fraction of 71%delivers a discharge capacity of 703 mAh g^(−1).In addition,at a high current rate of 0.5 C,a discharge capacity of 527 mAh g^(−1) is still maintained after 900 cycles with a very low capacity fading rate of 0.035%per cycle.
基金supported by the National Research Foundation of Korea grant funded by the Korea government(No.2019R1F1A1062998)。
文摘Objective:SC-E3 is a polyherbal formula that contains five medicinal herbs used frequently in traditional herbal medicine.In our previous study,we demonstrated the antioxidant and anti-inflammatory effects of SC-E3.The present study examined the effects of SC-E3 in a mouse model of type-II collagen-induced arthritis(CIA).Methods:In vivo,male DBA/1 J mice were immunized by intradermal injection of bovine type-II collagen and complete or incomplete Freund’s adjuvant,to induce arthritis.SC-E3 was orally administered daily for 23 days.In vitro,bone marrow-derived macrophages(BMMs)were treated with macrophage colony-stimulating factor(M-CSF)and receptor activator of nuclear factor-j B ligand(RANKL)in the absence or presence of SC-E3.Results:Administrations of SC-E3 were found to have anti-arthritic effects in the joints of CIA mice,as evidenced by reduced paw swelling,bone erosion and deformation,inflammatory cell infiltration,and inflammation in synovial membrane.SC-E3 also reduced serum levels of tumor necrosis factor-a,interleukin-1 b,aspartate aminotransferase and alanine aminotransferase.Furthermore,tartrateresistant acid phosphatase-positive osteoclast numbers in the joints were significantly lower in SC-E3-treated CIA mice than in CIA mice.In addition,the differentiations of BMMs to multinucleated osteoclasts induced by M-CSF and RANKL stimulation were dose-dependently reduced by SC-E3.Conclusion:These results suggest that SC-E3 possesses substantial anti-arthritic activity because it inhibits pro-inflammatory cytokines and osteoclastogenesis,and that SC-E3 has potential therapeutic use for the treatment of rheumatoid arthritis.