Diffusion-weighted imaging (DWI) as a new technique of magnetic resonance imaging (MRI) is used to detect focal hepatic lesions. This study was designed to evaluate the significance of DWI to differentiate focal hepat...Diffusion-weighted imaging (DWI) as a new technique of magnetic resonance imaging (MRI) is used to detect focal hepatic lesions. This study was designed to evaluate the significance of DWI to differentiate focal hepatic lesions less than 3 cm in diameter by the quantitation of apparent diffusion coefficient (ADC) values. METHODS:DWI using 1.5T MRI scanner unit was performed with a spin-echo single-shot echo planar imaging (EPI) in 56 cases of small focal hepatic lesions, including hepatocellular carcinoma (11), hepatic metastatic tumor (15 ), hepatic cavernous hemangioma (14), and hepatic cyst (16).The ADC values of these lesions were calculated respectively. The ratios of the ADC values of lesion/liver in hepatocellular carcinomas and hepatic metastatic tumors were also estimated. RESULTS:The mean ADC values (mm2/s) were (0.93±0.06) ×10-3 in hepatocellular carcinomas, (1.09±0.18)×10-3 in hepatic metastatic tumors,(1.95±0.38)×10-3 in hepatic cavernous hemangiomas, and (3.18±0.33) ×10-3 in hepatic cysts. The ratios of ADC values of lesion/liver were 0.90±0.06 and 1.15±0.14 in hepatocellular carcinoma and hepatic metastatic tumors respectively, which were significantly different (P<0.05). CONCLUSION:The measurement of ADC values and the ratios of ADC values of lesion/liver are helpful in MR diagnosis and differentiation of focal hepatic lesions.展开更多
The significance of source rocks for oil and gas accumulation has been indisputably acknowledged.Moreover,it has been gradually realized that there is difference between hydrocarbon generation capacity and hydrocarbon...The significance of source rocks for oil and gas accumulation has been indisputably acknowledged.Moreover,it has been gradually realized that there is difference between hydrocarbon generation capacity and hydrocarbon expulsion capacity,and this has prompted research on hydrocarbon expulsion efficiency.However,these studies dominantly highlight the results of hydrocarbon expulsion,and investigation into the corresponding process and mechanism is primarily from a macroscopic perspective.Despite its wide acceptance as the most direct hydrocarbon expulsion mode,hydrocarbon expulsion through micro-fractures is still not sufficiently understood.Therefore,this study obtains observations and performs experiments on two types of source rocks(mudstones and shales)of the Chang 7 oil group of the Yanchang Formation in Ordos Basin,China.Microscopy reveals that organic matter is non-uniformly distributed in both types of source rocks.Specifically,mudstones are characterized by a cluster-like organic matter distribution,whereas shales are characterized by a layered organic matter distribution.Thermal evolution simulation experiments demonstrate that the hydrocarbon generation process is accompanied by the emergence of micro-fractures,which are favorable for hydrocarbon expulsion.Moreover,based on the theories of rock physics and fracture mechanics,this study establishes micro-fracture development models for both types of source rocks,associated with the calculation of the fracture pressure that is needed for the initiation of fracture development.Furthermore,the relationship between the fluid pressure,fracture pressure,and micro-fracture expansion length during micro-fracture development is quantitatively explored,which helps identify the micro-fracture expansion length.The results indicate that the development of micro-fractures is commonly impacted by the morphology and distribution pattern of the organic matter as well as the mechanical properties of the source rocks.The micro-fractures in turn further affect the hydrocarbon expulsion capacity of the source rocks.The results of this study are expected to provide theoretical and practical guidance for the exploration and exploitation of tight oil and shale oil.展开更多
The fast developing remote sensing techniques play an increasingly important role in earthquake emergency response, disaster survey and loss estimation. As there is a lack of quantitative studies on seismic damage bas...The fast developing remote sensing techniques play an increasingly important role in earthquake emergency response, disaster survey and loss estimation. As there is a lack of quantitative studies on seismic damage based on remote sensing, its practicality in seismic disaster management has usually been questioned. The paper introduces the essential quantitative study idea, the concept of the remote sensing seismic damage index （D1RS） and analysis models, demonstrates the seismic damage indices （ D1G ） of buildings obtained from ground surveying and its quantitative relation to D1RS in Dujiangyan city, Sichuan Province, which was destroyed by the 2008 Wenchuan earthquake with Ms8.0. The primary results show that an obvious relationship exists between the D1RS of buildings obtained from the high resolution satellite or aerial remote sensing images and D1G or the building collapse ratio obtained through ground survey, which suggests that the quantitative study on seismic damage based on remote sensing will provide an effective method for seismic damage survey and loss estimation.展开更多
A method for quantitative evaluating the enhancement of the rate of Type Ⅱ photosensitized oxidation by D_2O was suggested. The effect of substrate concentration on this process was also discussed.
Objective Nowadays, high-resolution remote sensing technology has brought new changes to surveys of earthquakes, and the quantitative study of seismic faults based on this technology has become a trend in the world(Ba...Objective Nowadays, high-resolution remote sensing technology has brought new changes to surveys of earthquakes, and the quantitative study of seismic faults based on this technology has become a trend in the world(Barzegari et al., 2017). An Mw 7.2 earthquake occurred in Yutian of Xinjiang on the western end of the Altyn Tagh fault on March 21 st, 2008. It is difficult to access this depopulated zone because of the high altitude and only 1–2 months of snowmelt. This study utilized high-resolution展开更多
The mechanism for investment, utilization, and management of devices and equipment in universities is different from that of enterprises, because the devices and equipment inuniversities are rarely used for profit. It...The mechanism for investment, utilization, and management of devices and equipment in universities is different from that of enterprises, because the devices and equipment inuniversities are rarely used for profit. It is necessary to establish a new mode for the management of university-owned equipment. Such a mode consists of both technical management and economic management. To this end, the utilization of devices and equipment in the First Military Medical University is investigated qualitatively and quantitatively. The criterion-integrated index for the utilization of equipment is proposed for the first time. By using this criterion, together with such criteria as 'quality index', 'idleness index', and 'average usage index' the utilization and management of each class of equipment are described quantitatively.展开更多
The argyrophilic staining technique was used in differential diagnosis between non-odgkin's lymphoraa (NHL) and reactive hyperplasia (RH) of lymphatic tissues in 30 cases of RH and 71 cases of NHL which were class...The argyrophilic staining technique was used in differential diagnosis between non-odgkin's lymphoraa (NHL) and reactive hyperplasia (RH) of lymphatic tissues in 30 cases of RH and 71 cases of NHL which were classified as low (11 cases), moderate (49 cases) and high malignant (11 cases) groups. The mumber and the area of Ag nucleolar organizer region (AgNORs) in 100 cells of each case were examined by both IBAS-200 cytoimage analyser and microscope. The results showed that there was significant difference in the number, but not in area, of AgNOR granules between RH and low malignant group of NHL (P< 0.001). In NHL, the significant differences in the number and area of AgNORs were found between each groups (P<0.05 or P< 0.001). It was also observed that in NHL, the number of AgNOR was negatively correlated with the area of the granules, and the shapes and distribution patterns of AgNOR were significantly different between each groups. Our results suggest that the quantitative study of AgNOR combining with the histological characteristics is very helpful in the differential diagnosis of RH and NHL and in the classification of NHL.展开更多
Duplex stainless steels(DSSs)are suffering from various localized corrosion attacks such as pitting,selective dissolution,crevice corrosion during their service period.It is of great value to quantitatively analyze an...Duplex stainless steels(DSSs)are suffering from various localized corrosion attacks such as pitting,selective dissolution,crevice corrosion during their service period.It is of great value to quantitatively analyze and grasp the micro-electrochemical corrosion behavior and related mechanism for DSSs on the micrometer or even smaller scales.In this work,scanning Kelvin probe force microscopy(SKPFM)and energy dispersive spectroscopy(EDS)measurements were performed to reveal the difference between the austenite phase and ferrite phase in microregion of DSS 2205.Then traditional electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization(PDP)tests were employed for micro-electrochemical characterization of DSS 2205 with different proportion phases inϕ40 andϕ10μm micro holes.Both of them can only be utilized for qualitative or semi-quantitative micro-electrochemical characterization of DSS 2205.Coulostatic perturbation method was employed for quantitative micro-electrochemical characterization of DSS 2205.What is more,the applicable conditions of coulostatic perturbation were analyzed in depth by establishing a detailed electrochemical interface circuit.A series of microregion coulostatic perturbations for DSS 2205 with different proportion phases inϕ10μm micro holes showed that as the austenite proportion increases,the corresponding polarization resistance of microregion increases linearly.展开更多
The differences in intracellular and extracellular protein expressions between human prostate cancer lines LNCap and DU145 were examined, The proteins of the two cell lines were extracted and condensed by using protei...The differences in intracellular and extracellular protein expressions between human prostate cancer lines LNCap and DU145 were examined, The proteins of the two cell lines were extracted and condensed by using protein extraction kits. And the intracellular and extracellular proteins were quantitatively detected on a micro-plate reader by using bicinchoninic acid （BCA） method. The proteins in cell culture fluid were qualitatively assayed by SELDI-TOF-MS, The results showed that the intracellular protein contents of LNCap cells were extremely higher than those of DU145 cells. After serum-free culture, both intracellular and extracellular protein contents of LNCap and DU145 were decreased to some extent. And the intracellular proteins were decreased by 5% in LNCap and by 36% in DU145 respectively, while the extracellular proteins were decreased by 89% in LNCap and 96% in DU145 respectively. SELDI assay revealed that there were 5 marker proteins in LNCap and 6 in DU145. Although both LNCap and DU145 cell lines originated from human prostate cancer, they had some differences in protein expression.展开更多
After several former studies on the cognitive heuristics and correlating economical influences,the explanatory effectiveness of Status Quo Bias perspective is explained by multiple empirical scenarios.Hence,this essay...After several former studies on the cognitive heuristics and correlating economical influences,the explanatory effectiveness of Status Quo Bias perspective is explained by multiple empirical scenarios.Hence,this essay will focus on three applications in which the Status Quo Bias perspective,correlating models,and research methods would provide insightful opinions.After reviewing the former attempts on the original model and early researchers’empirical examination on the Status Quo Bias,this essay will concentrate on Status Quo Bias and technology resistance among the public sector employees,Status Quo Bias and medical insurance outcomes,Status Quo Bias and shoppers’mobile website purchasing resistance respectively.For each application,research methodology will be explained and be integrated into the Status Quo Bias perspective through the research question.Through researching on these applications’methodology and main studies,discussing cognitive biases existing in the empirical scenarios,the present study could approach to the efficiency of the explanation from Status Quo Bias perspective.展开更多
Background: Orthodontics is a dental specialty focusing on correcting dental irregularities and malocclusion. Knowledge and attitudes towards orthodontic treatment are crucial for promoting oral health and overall wel...Background: Orthodontics is a dental specialty focusing on correcting dental irregularities and malocclusion. Knowledge and attitudes towards orthodontic treatment are crucial for promoting oral health and overall well-being. Education and awareness play a vital role in ensuring optimal treatment outcomes and improving quality of life. Aim: This study aims to determine the knowledge and attitudes of Kwame Nkrumah University of Science and Technology (KNUST) pre-clinical dentistry students concerning orthodontic therapy. Methodology: This research is a quantitative descriptive cross-sectional study. The research used a non-random convenience sampling method to form the desired sample. For data collection, an interview-administered questionnaire was used over one month. The study set its sights on pre-clinical dental students in KNUST. A total of 150 questionnaires were printed to meet the sample size. Results: The results of the research showed that the knowledge level of KNUST pre-clinical students on orthodontic treatment and its nuances is quite limited. They however had a fair level of knowledge on the disease or ailment that orthodontic treatments solved (especially malocclusion). Their interest in orthodontic treatments on the other hand was quite significant, with a large number having interest in it. Conclusion: To conclude, KNUST pre-clinical students in Ghana although having a limited level of knowledge on orthodontic treatments have a keen interest in undergoing them regardless of the discomforts or the length of time.展开更多
BACKGROUND The value of conventional magnetic resonance imaging in the differential diagnosis of thyroid nodules is limited;however,the value of multi-parameter diffusion-weighted imaging(DWI)in the quantitative evalu...BACKGROUND The value of conventional magnetic resonance imaging in the differential diagnosis of thyroid nodules is limited;however,the value of multi-parameter diffusion-weighted imaging(DWI)in the quantitative evaluation of thyroid nodules has not been well determined.AIM To determine the utility of multi-parametric DWI including mono-exponential,biexponential,stretched exponential,and kurtosis models for the differentiation of thyroid lesions.METHODS Seventy-nine patients(62 with benign and 17 with malignant nodules)underwent multi-b value diffusion-weighted imaging of the thyroid.Multiple DWI parameters were obtained for statistical analysis.RESULTS Good agreement was found for diffusion parameters of thyroid nodules.Malignant lesions displayed lower diffusion parameters including apparent diffusion coefficient(ADC),the true diffusion coefficient(D),the perfusion fraction(f),the distributed diffusion coefficient(DDC),the intravoxel water diffusion heterogeneity(α)and kurtosis model-derived ADC(Dapp),and higher apparent diffusional kurtosis(Kapp)than benign entities(all P<0.01),except for the pseudodiffusion coefficient(D*)(P>0.05).The area under the ROC curve(AUC)of the ADC(0 and 1000)was not significantly different from that of the ADC(0 and 2000),ADC(0 to 2000),ADC(0 to 1000),D,DDC,Dapp and Kapp(all P>0.05),but was significantly higher than the AUC of D*,f andα(all P<0.05)for differentiating benign from malignant lesions.CONCLUSION Multiple DWI parameters including ADC,D,f,DDC,α,Dapp and Kapp could discriminate benign and malignant thyroid nodules.The metrics including D,DDC,Dapp and Kapp provide additional information with similar diagnostic performance of ADC,combination of these metrics may contribute to differentiate benign and malignant thyroid nodules.The ADC calculated with higher b values may not lead to improved diagnostic performance.展开更多
Fuzzy mathematics is an important means to quantitatively evaluate the properties of fault sealing in petroleum reservoirs.To accurately study fault sealing,the comprehensive quantitative evaluation method of fuzzy ma...Fuzzy mathematics is an important means to quantitatively evaluate the properties of fault sealing in petroleum reservoirs.To accurately study fault sealing,the comprehensive quantitative evaluation method of fuzzy mathematics is improved based on a previous study.First,the single-factor membership degree is determined using the dynamic clustering method,then a single-factor evaluation matrix is constructed using a continuous grading function,and finally,the probability distribution of the evaluation grade in a fuzzy evaluation matrix is analyzed.In this study,taking the F1 fault located in the northeastern Chepaizi Bulge as an example,the sealing properties of faults in different strata are quantitatively evaluated using both an improved and an un-improved comprehensive fuzzy mathematics quantitative evaluation method.Based on current oil and gas distribution,it is found that our evaluation results before and after improvement are significantly different.For faults in＂best＂and＂poorest＂intervals,our evaluation results are consistent with oil and gas distribution.However,for the faults in＂good＂or＂poor＂intervals,our evaluation is not completelyconsistent with oil and gas distribution.The improved evaluation results reflect the overall and local sealing properties of target zones and embody the nonuniformity of fault sealing,indicating the improved method is more suitable for evaluating fault sealing under complicated conditions.展开更多
Objective:Research suggests that caregivers of children with asthma experience a substantial amount of stress,though no comprehensive study examines this problem.Here we both quantitatively and qualitatively examined ...Objective:Research suggests that caregivers of children with asthma experience a substantial amount of stress,though no comprehensive study examines this problem.Here we both quantitatively and qualitatively examined the burden on caregivers of children with asthma.Methods:Surveys were administered to 138 caregivers of asthmatic children by convenience sampling.The Zarit Caregiver Burden Interview(ZBI)was used to assess the degree of caregiver burden.In addition,13 qualitative semi-structured interviews were carried out via purposive sampling and were used to explore the perception of caregivers.SPSS and content analysis were used to analyze quantitative and qualitative data,respectively.Results:We found that caregiver burden(mean=31.56±14.19)ranged from 24%with no or mild burden,52%with mild to moderate burden,22%with moderate to severe burden and 2%with very severe burden.Caregiver burden was also assessed as 5 different dimensions.Selfcriticism ranked most burdensome(2.09±1.05),followed by sacrifice(1.57±0.94),embarrassment/anger(1.30±0.80),dependency(1.21±0.77),and lastly,loss of control(1.20±0.84).The highest individually scored item on the ZBI was“fear of the future of the relative”(mean=3.04).Interviews of caregiver burden were summarized into three main themes,namely:1)life is too chaotic;2)negative emotions;and 3)gaps in themedical support system.Conclusions:These findings expand our understanding about the burden caregivers of children with asthma face,and may help to propose targeted strategies to help caregivers adapt to their roles,and maintain and promote the health of themselves and their families.展开更多
Objective To study the feasibility of enforcing immunization certificate check before children enroll in primary schools or kindergartens in Guizhou Province. Methods Quantitative and qualitative studies were conducte...Objective To study the feasibility of enforcing immunization certificate check before children enroll in primary schools or kindergartens in Guizhou Province. Methods Quantitative and qualitative studies were conducted. The multi-stage and cluster sampling approach was adopted for the quantitative part of the study. A questionnaire was designed and 996 children and their keepers were interviewed. Principals, doctors or teachers of the primary schools, directors and child care nurses of kindergarten, and staff of immunization agencies were invited to take part in 12 focus group discussions; meanwhile, face-to-face individual in-depth interviews with 16 officials of the Health, Education and Governmental Departments at various levels were conducted. Results The total number of subjects was 996. 16.7% of the children in the study completed all the procedures of the National Immunization Programme. 34.3% of them had immunization certificates while the remainder 44.7% registered in immunization agencies. Factors, including the migrant children, doubt about vaccine efficiency, mother’s occupation and educational background, knowledge of the National Immunization Programme on targeted vaccines, played an important role in obtaining or not immunization certificates. 95% of the keepers interviewed thought the immunization certificates were useful; 94.8% of them considered the check was critical while only 3.6% of them thought it unnecessary. The first reason from those who found it unnecessary was that they feared that repeated immunization might affect their children’s health. The second reason was the cost of immunization, which some of them could not afford to pay. However, the Health Department expressed a favorable attitude to the checking scheme. Though the Education Department agreed that the scheme was essential, they worried that it would affect the enrollment rate.Conclusion In spite of the difficulty in administering immunization certificate check, the effort would be rewarding for raising the immunization coverage rate among the children in Guizhou Province.展开更多
Mating behavior and parturition are important components in the life history of any species. The endangered Chinese crocodile lizard(Shinisaurus crocodilurus) is suffering dramatic population decreases in the wild. Su...Mating behavior and parturition are important components in the life history of any species. The endangered Chinese crocodile lizard(Shinisaurus crocodilurus) is suffering dramatic population decreases in the wild. Successful captive breeding can provide individuals to be reintroduced into their natural habitat and help to restore the wild populations. Studying the mating behavior and parturition of these lizards in captivity will enable us understand how is this ancient species reproduction and optimize artificial reproduction protocol. We studied the mating behavior and parturition of Chinese crocodile lizards in captivity using video recordings at the Daguishan National Nature Reserve, China, from 2015 to 2017. We analyzed pre-copulation and copulation, which occurred in mid-March to late May from all studied years. Pre-copulation and copulation lasted on average 7.51(n=11) and 27.45(n=11) minutes, respectively. We found that large-bodied male lizards have longer copulation periods, a pattern seen in other lizard species. In the mating event, males always initiated sex, while the females were passive. The duration of parturition lasted 153.8 ± 26.8(n=46) minutes, and larger females had heavier clutches. In addition, even though Chinese crocodile lizards represent an ancient lizard clade with primitive characteristics, they still abide by the reproduction patterns seen in most other lizard species.展开更多
The DNA content and morphometric features of hepatocellular carcinoma (HCC) and liver cell dysplasia (LCD), including nuclear area, nuclear perimeter, nuclear maximum diameter and nuclear circle diameter, were quantit...The DNA content and morphometric features of hepatocellular carcinoma (HCC) and liver cell dysplasia (LCD), including nuclear area, nuclear perimeter, nuclear maximum diameter and nuclear circle diameter, were quantitatively determined by means of image analysis technology. The results showed that in comparison with normal hepatocytes, LCD had a markedly increased DNA content and nuclear morphometric parameters, but the values were lower than those for HCC. LCD showed a slight increase in nuclear atypia represented by the nuclear irregular index, which was also less than HCC. The findings indicate that LCD may be a precaneerous lesion of HCC, to the cells in an abnormal proliferative state.展开更多
Charcoal is commonly preserved in both natural and artificial sediments,and is intensively used in paleontological,paleoenvironmental,and archaeological studies due to the abundant bio-information it contains.The bioc...Charcoal is commonly preserved in both natural and artificial sediments,and is intensively used in paleontological,paleoenvironmental,and archaeological studies due to the abundant bio-information it contains.The biochemical properties of charcoal are also used for paleoclimatic reconstruction;however,the reliability of this approach has been challenged due to a lack of clarity on how physicochemical properties change during the charring process,as well as the temperatures required for charcoalification.To address this lack,in this study,Qinghai spruce and Chinese pine wood samples from the northeastern Tibetan Plateau were heated at different temperatures and for different lengths of time under restricted oxygen conditions.The reflectance;carbon,nitrogen,and oxygen content;and tracheid morphology were quantified before and after heating to assess changes related to the charring process.Archaeological charcoal remains were then evaluated to determine the charcoalification temperatures by comparing with the experimental results.The minimum temperature required for wood charcoalification was∼300℃,while temperatures recorded by archaeological charcoal were concentrated at 400-500℃.During the charring experiments,the tracheid cell walls gradually homogenized,and tracheid cell wall thickness and lumen area decreased by∼20%.On average,50%mass losses were observed;the carbon and oxygen content(%wt.)approximately changed from 47%to 60%and 48%to 35%respectively,while the nitrogen content(%wt.)fluctuated around 0.2%.The reflectance increased slightly from 0%to 0.5%.We propose that the charcoalification of wood tissue refers to charring(in restricted air)and carbonization(in the almost absence of air)when the wood is exposed to a heat source,which then finally transforms into a black,inert solid.This quantitative study provided valuable data and a thorough assessment of the process of wood charcoalification,as well as accurately estimated the feasibility of using charcoal physicochemical properties in paleoclimatic research.展开更多
The literature illustrates the important issue of physician adherence to guidelines in their daily practice. In a quantitative study, we asked a random sample of 100 hospital gastroenterologists to evaluate their know...The literature illustrates the important issue of physician adherence to guidelines in their daily practice. In a quantitative study, we asked a random sample of 100 hospital gastroenterologists to evaluate their knowledge of guidelines and awareness of promoters. The degree to which guidelines were considered reliable was not related to the scientific evidence but was significantly associated with the promoter. The French Society of Gastroenterology was considered to be a more reliable promoter than national health agencies and pharmaceutical industries. Gastroenterologists become aware of guidelines mainly through their specialty society (62%). Specialty societies appear to be a more important source of information on guidelines for physicians. National health agencies should involve the specialty societies in the guideline development process to achieve changes in clinical practice.展开更多
Objective:The effect of ankle rehabilitation robot on joint movement of hemiplegic patients was studied and quantitatively evaluated.Methods 90 hemiplegic patients with lower limb dysfunction treated in our hospital f...Objective:The effect of ankle rehabilitation robot on joint movement of hemiplegic patients was studied and quantitatively evaluated.Methods 90 hemiplegic patients with lower limb dysfunction treated in our hospital from April 2017 to March 2019 were selected as subjects.The patients were randomly divided into two groups:control group(n=45)and observation group(n=45).The patients in the two groups received language training,physiotherapy,exercise therapy,spa,occupational therapy,massage and other comprehensive rehabilitation treatment,on the basis of which the observation group received the auxiliary intervention of ankle rehabilitation robot.The soft tissue compliance of the patients was evaluated by ankle metatarsal flexion moment before and after treatment,the metatarsal flexor tension was evaluated by modified Tardieu scale,and the clinical effect was evaluated by ankle active ankle dorsiflexion.Results After treatment,the ankle flexion angles(0°,10°,20°,30°)in the two groups were significantly lower than those in the control group(P<0.05).Results compared with before treatment,the ankle flexion angles(0°,10°,20°,30°)in the two groups were significantly lower than those in the control group(P<0.05).After treatment,the angle of R1 and R2 measured by modified Tardieu scale of ankle plantar flexor group increased significantly,and the difference of R2-R1 decreased significantly(P<0.05).The improvement degree of the observation group was significantly better than that of the control group(P<0.05).After treatment,the active ankle extension activity of the two groups was significantly higher than that before treatment(P<0.05),and the effective rate of the observation group was significantly higher than that of the observation group(P<0.05).Conclusion Auxiliary intervention with ankle rehabilitation robot system can effectively improve the compliance of ankle soft tissue in spastic hemiplegia,reduce the contracture of metatarsal flexor muscle and improve the disturbance of joint movement in a short time.At the same time,the degree of coordination and acceptance of patients and their families is high,which is an effective means to improve the therapeutic effect.展开更多
基金This study was supported by the Natural Science Foundation of Guangdong Province, China (No.101595 and No. 32830).
文摘Diffusion-weighted imaging (DWI) as a new technique of magnetic resonance imaging (MRI) is used to detect focal hepatic lesions. This study was designed to evaluate the significance of DWI to differentiate focal hepatic lesions less than 3 cm in diameter by the quantitation of apparent diffusion coefficient (ADC) values. METHODS:DWI using 1.5T MRI scanner unit was performed with a spin-echo single-shot echo planar imaging (EPI) in 56 cases of small focal hepatic lesions, including hepatocellular carcinoma (11), hepatic metastatic tumor (15 ), hepatic cavernous hemangioma (14), and hepatic cyst (16).The ADC values of these lesions were calculated respectively. The ratios of the ADC values of lesion/liver in hepatocellular carcinomas and hepatic metastatic tumors were also estimated. RESULTS:The mean ADC values (mm2/s) were (0.93±0.06) ×10-3 in hepatocellular carcinomas, (1.09±0.18)×10-3 in hepatic metastatic tumors,(1.95±0.38)×10-3 in hepatic cavernous hemangiomas, and (3.18±0.33) ×10-3 in hepatic cysts. The ratios of ADC values of lesion/liver were 0.90±0.06 and 1.15±0.14 in hepatocellular carcinoma and hepatic metastatic tumors respectively, which were significantly different (P<0.05). CONCLUSION:The measurement of ADC values and the ratios of ADC values of lesion/liver are helpful in MR diagnosis and differentiation of focal hepatic lesions.
基金financially supported by National Natural Science Foundation of China(Grant Nos.41572137,41872165)National Science and Technology Major Project of China(Grant No.2017ZX05001002-003)Research and Innovation fund for Graduate Students of Southwest Petroleum University(Grant No.2019cxyb006)。
文摘The significance of source rocks for oil and gas accumulation has been indisputably acknowledged.Moreover,it has been gradually realized that there is difference between hydrocarbon generation capacity and hydrocarbon expulsion capacity,and this has prompted research on hydrocarbon expulsion efficiency.However,these studies dominantly highlight the results of hydrocarbon expulsion,and investigation into the corresponding process and mechanism is primarily from a macroscopic perspective.Despite its wide acceptance as the most direct hydrocarbon expulsion mode,hydrocarbon expulsion through micro-fractures is still not sufficiently understood.Therefore,this study obtains observations and performs experiments on two types of source rocks(mudstones and shales)of the Chang 7 oil group of the Yanchang Formation in Ordos Basin,China.Microscopy reveals that organic matter is non-uniformly distributed in both types of source rocks.Specifically,mudstones are characterized by a cluster-like organic matter distribution,whereas shales are characterized by a layered organic matter distribution.Thermal evolution simulation experiments demonstrate that the hydrocarbon generation process is accompanied by the emergence of micro-fractures,which are favorable for hydrocarbon expulsion.Moreover,based on the theories of rock physics and fracture mechanics,this study establishes micro-fracture development models for both types of source rocks,associated with the calculation of the fracture pressure that is needed for the initiation of fracture development.Furthermore,the relationship between the fluid pressure,fracture pressure,and micro-fracture expansion length during micro-fracture development is quantitatively explored,which helps identify the micro-fracture expansion length.The results indicate that the development of micro-fractures is commonly impacted by the morphology and distribution pattern of the organic matter as well as the mechanical properties of the source rocks.The micro-fractures in turn further affect the hydrocarbon expulsion capacity of the source rocks.The results of this study are expected to provide theoretical and practical guidance for the exploration and exploitation of tight oil and shale oil.
基金sponsored by the tenth Five-year Plan of Special Social Commonweal Research Programs of the State (2006BAC13B03-01-01)
文摘The fast developing remote sensing techniques play an increasingly important role in earthquake emergency response, disaster survey and loss estimation. As there is a lack of quantitative studies on seismic damage based on remote sensing, its practicality in seismic disaster management has usually been questioned. The paper introduces the essential quantitative study idea, the concept of the remote sensing seismic damage index （D1RS） and analysis models, demonstrates the seismic damage indices （ D1G ） of buildings obtained from ground surveying and its quantitative relation to D1RS in Dujiangyan city, Sichuan Province, which was destroyed by the 2008 Wenchuan earthquake with Ms8.0. The primary results show that an obvious relationship exists between the D1RS of buildings obtained from the high resolution satellite or aerial remote sensing images and D1G or the building collapse ratio obtained through ground survey, which suggests that the quantitative study on seismic damage based on remote sensing will provide an effective method for seismic damage survey and loss estimation.
文摘A method for quantitative evaluating the enhancement of the rate of Type Ⅱ photosensitized oxidation by D_2O was suggested. The effect of substrate concentration on this process was also discussed.
基金supported by the National Natural Science Foundation of China (grants No. 41461164002 and 41631073)
文摘Objective Nowadays, high-resolution remote sensing technology has brought new changes to surveys of earthquakes, and the quantitative study of seismic faults based on this technology has become a trend in the world(Barzegari et al., 2017). An Mw 7.2 earthquake occurred in Yutian of Xinjiang on the western end of the Altyn Tagh fault on March 21 st, 2008. It is difficult to access this depopulated zone because of the high altitude and only 1–2 months of snowmelt. This study utilized high-resolution
文摘The mechanism for investment, utilization, and management of devices and equipment in universities is different from that of enterprises, because the devices and equipment inuniversities are rarely used for profit. It is necessary to establish a new mode for the management of university-owned equipment. Such a mode consists of both technical management and economic management. To this end, the utilization of devices and equipment in the First Military Medical University is investigated qualitatively and quantitatively. The criterion-integrated index for the utilization of equipment is proposed for the first time. By using this criterion, together with such criteria as 'quality index', 'idleness index', and 'average usage index' the utilization and management of each class of equipment are described quantitatively.
文摘The argyrophilic staining technique was used in differential diagnosis between non-odgkin's lymphoraa (NHL) and reactive hyperplasia (RH) of lymphatic tissues in 30 cases of RH and 71 cases of NHL which were classified as low (11 cases), moderate (49 cases) and high malignant (11 cases) groups. The mumber and the area of Ag nucleolar organizer region (AgNORs) in 100 cells of each case were examined by both IBAS-200 cytoimage analyser and microscope. The results showed that there was significant difference in the number, but not in area, of AgNOR granules between RH and low malignant group of NHL (P< 0.001). In NHL, the significant differences in the number and area of AgNORs were found between each groups (P<0.05 or P< 0.001). It was also observed that in NHL, the number of AgNOR was negatively correlated with the area of the granules, and the shapes and distribution patterns of AgNOR were significantly different between each groups. Our results suggest that the quantitative study of AgNOR combining with the histological characteristics is very helpful in the differential diagnosis of RH and NHL and in the classification of NHL.
基金financial support from the Ministry of Science and Technology, China for the national key research and development plan (No. 2017YFB0701904)China Nuclear Power Engineering Co., Ltd. (No. KY1672)the 111 Project (No. B12012)
文摘Duplex stainless steels(DSSs)are suffering from various localized corrosion attacks such as pitting,selective dissolution,crevice corrosion during their service period.It is of great value to quantitatively analyze and grasp the micro-electrochemical corrosion behavior and related mechanism for DSSs on the micrometer or even smaller scales.In this work,scanning Kelvin probe force microscopy(SKPFM)and energy dispersive spectroscopy(EDS)measurements were performed to reveal the difference between the austenite phase and ferrite phase in microregion of DSS 2205.Then traditional electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization(PDP)tests were employed for micro-electrochemical characterization of DSS 2205 with different proportion phases inϕ40 andϕ10μm micro holes.Both of them can only be utilized for qualitative or semi-quantitative micro-electrochemical characterization of DSS 2205.Coulostatic perturbation method was employed for quantitative micro-electrochemical characterization of DSS 2205.What is more,the applicable conditions of coulostatic perturbation were analyzed in depth by establishing a detailed electrochemical interface circuit.A series of microregion coulostatic perturbations for DSS 2205 with different proportion phases inϕ10μm micro holes showed that as the austenite proportion increases,the corresponding polarization resistance of microregion increases linearly.
文摘The differences in intracellular and extracellular protein expressions between human prostate cancer lines LNCap and DU145 were examined, The proteins of the two cell lines were extracted and condensed by using protein extraction kits. And the intracellular and extracellular proteins were quantitatively detected on a micro-plate reader by using bicinchoninic acid （BCA） method. The proteins in cell culture fluid were qualitatively assayed by SELDI-TOF-MS, The results showed that the intracellular protein contents of LNCap cells were extremely higher than those of DU145 cells. After serum-free culture, both intracellular and extracellular protein contents of LNCap and DU145 were decreased to some extent. And the intracellular proteins were decreased by 5% in LNCap and by 36% in DU145 respectively, while the extracellular proteins were decreased by 89% in LNCap and 96% in DU145 respectively. SELDI assay revealed that there were 5 marker proteins in LNCap and 6 in DU145. Although both LNCap and DU145 cell lines originated from human prostate cancer, they had some differences in protein expression.
文摘After several former studies on the cognitive heuristics and correlating economical influences,the explanatory effectiveness of Status Quo Bias perspective is explained by multiple empirical scenarios.Hence,this essay will focus on three applications in which the Status Quo Bias perspective,correlating models,and research methods would provide insightful opinions.After reviewing the former attempts on the original model and early researchers’empirical examination on the Status Quo Bias,this essay will concentrate on Status Quo Bias and technology resistance among the public sector employees,Status Quo Bias and medical insurance outcomes,Status Quo Bias and shoppers’mobile website purchasing resistance respectively.For each application,research methodology will be explained and be integrated into the Status Quo Bias perspective through the research question.Through researching on these applications’methodology and main studies,discussing cognitive biases existing in the empirical scenarios,the present study could approach to the efficiency of the explanation from Status Quo Bias perspective.
文摘Background: Orthodontics is a dental specialty focusing on correcting dental irregularities and malocclusion. Knowledge and attitudes towards orthodontic treatment are crucial for promoting oral health and overall well-being. Education and awareness play a vital role in ensuring optimal treatment outcomes and improving quality of life. Aim: This study aims to determine the knowledge and attitudes of Kwame Nkrumah University of Science and Technology (KNUST) pre-clinical dentistry students concerning orthodontic therapy. Methodology: This research is a quantitative descriptive cross-sectional study. The research used a non-random convenience sampling method to form the desired sample. For data collection, an interview-administered questionnaire was used over one month. The study set its sights on pre-clinical dental students in KNUST. A total of 150 questionnaires were printed to meet the sample size. Results: The results of the research showed that the knowledge level of KNUST pre-clinical students on orthodontic treatment and its nuances is quite limited. They however had a fair level of knowledge on the disease or ailment that orthodontic treatments solved (especially malocclusion). Their interest in orthodontic treatments on the other hand was quite significant, with a large number having interest in it. Conclusion: To conclude, KNUST pre-clinical students in Ghana although having a limited level of knowledge on orthodontic treatments have a keen interest in undergoing them regardless of the discomforts or the length of time.
基金Supported by the Health Commission of Zhejiang Province,No.2019KY690。
文摘BACKGROUND The value of conventional magnetic resonance imaging in the differential diagnosis of thyroid nodules is limited;however,the value of multi-parameter diffusion-weighted imaging(DWI)in the quantitative evaluation of thyroid nodules has not been well determined.AIM To determine the utility of multi-parametric DWI including mono-exponential,biexponential,stretched exponential,and kurtosis models for the differentiation of thyroid lesions.METHODS Seventy-nine patients(62 with benign and 17 with malignant nodules)underwent multi-b value diffusion-weighted imaging of the thyroid.Multiple DWI parameters were obtained for statistical analysis.RESULTS Good agreement was found for diffusion parameters of thyroid nodules.Malignant lesions displayed lower diffusion parameters including apparent diffusion coefficient(ADC),the true diffusion coefficient(D),the perfusion fraction(f),the distributed diffusion coefficient(DDC),the intravoxel water diffusion heterogeneity(α)and kurtosis model-derived ADC(Dapp),and higher apparent diffusional kurtosis(Kapp)than benign entities(all P<0.01),except for the pseudodiffusion coefficient(D*)(P>0.05).The area under the ROC curve(AUC)of the ADC(0 and 1000)was not significantly different from that of the ADC(0 and 2000),ADC(0 to 2000),ADC(0 to 1000),D,DDC,Dapp and Kapp(all P>0.05),but was significantly higher than the AUC of D*,f andα(all P<0.05)for differentiating benign from malignant lesions.CONCLUSION Multiple DWI parameters including ADC,D,f,DDC,α,Dapp and Kapp could discriminate benign and malignant thyroid nodules.The metrics including D,DDC,Dapp and Kapp provide additional information with similar diagnostic performance of ADC,combination of these metrics may contribute to differentiate benign and malignant thyroid nodules.The ADC calculated with higher b values may not lead to improved diagnostic performance.
基金supported by the Science and Technology Project of Universities and Colleges in Shandong Province ‘‘Investigation on diagenetic environment and transformation pattern of red-bed reservoirs in the rift basins’’ (No. J16LH52)
文摘Fuzzy mathematics is an important means to quantitatively evaluate the properties of fault sealing in petroleum reservoirs.To accurately study fault sealing,the comprehensive quantitative evaluation method of fuzzy mathematics is improved based on a previous study.First,the single-factor membership degree is determined using the dynamic clustering method,then a single-factor evaluation matrix is constructed using a continuous grading function,and finally,the probability distribution of the evaluation grade in a fuzzy evaluation matrix is analyzed.In this study,taking the F1 fault located in the northeastern Chepaizi Bulge as an example,the sealing properties of faults in different strata are quantitatively evaluated using both an improved and an un-improved comprehensive fuzzy mathematics quantitative evaluation method.Based on current oil and gas distribution,it is found that our evaluation results before and after improvement are significantly different.For faults in＂best＂and＂poorest＂intervals,our evaluation results are consistent with oil and gas distribution.However,for the faults in＂good＂or＂poor＂intervals,our evaluation is not completelyconsistent with oil and gas distribution.The improved evaluation results reflect the overall and local sealing properties of target zones and embody the nonuniformity of fault sealing,indicating the improved method is more suitable for evaluating fault sealing under complicated conditions.
基金Funding was provided for this manuscript:We receive the fund of Science and technology department of Guangdong province,NO.2014A020212366.
文摘Objective:Research suggests that caregivers of children with asthma experience a substantial amount of stress,though no comprehensive study examines this problem.Here we both quantitatively and qualitatively examined the burden on caregivers of children with asthma.Methods:Surveys were administered to 138 caregivers of asthmatic children by convenience sampling.The Zarit Caregiver Burden Interview(ZBI)was used to assess the degree of caregiver burden.In addition,13 qualitative semi-structured interviews were carried out via purposive sampling and were used to explore the perception of caregivers.SPSS and content analysis were used to analyze quantitative and qualitative data,respectively.Results:We found that caregiver burden(mean=31.56±14.19)ranged from 24%with no or mild burden,52%with mild to moderate burden,22%with moderate to severe burden and 2%with very severe burden.Caregiver burden was also assessed as 5 different dimensions.Selfcriticism ranked most burdensome(2.09±1.05),followed by sacrifice(1.57±0.94),embarrassment/anger(1.30±0.80),dependency(1.21±0.77),and lastly,loss of control(1.20±0.84).The highest individually scored item on the ZBI was“fear of the future of the relative”(mean=3.04).Interviews of caregiver burden were summarized into three main themes,namely:1)life is too chaotic;2)negative emotions;and 3)gaps in themedical support system.Conclusions:These findings expand our understanding about the burden caregivers of children with asthma face,and may help to propose targeted strategies to help caregivers adapt to their roles,and maintain and promote the health of themselves and their families.
文摘Objective To study the feasibility of enforcing immunization certificate check before children enroll in primary schools or kindergartens in Guizhou Province. Methods Quantitative and qualitative studies were conducted. The multi-stage and cluster sampling approach was adopted for the quantitative part of the study. A questionnaire was designed and 996 children and their keepers were interviewed. Principals, doctors or teachers of the primary schools, directors and child care nurses of kindergarten, and staff of immunization agencies were invited to take part in 12 focus group discussions; meanwhile, face-to-face individual in-depth interviews with 16 officials of the Health, Education and Governmental Departments at various levels were conducted. Results The total number of subjects was 996. 16.7% of the children in the study completed all the procedures of the National Immunization Programme. 34.3% of them had immunization certificates while the remainder 44.7% registered in immunization agencies. Factors, including the migrant children, doubt about vaccine efficiency, mother’s occupation and educational background, knowledge of the National Immunization Programme on targeted vaccines, played an important role in obtaining or not immunization certificates. 95% of the keepers interviewed thought the immunization certificates were useful; 94.8% of them considered the check was critical while only 3.6% of them thought it unnecessary. The first reason from those who found it unnecessary was that they feared that repeated immunization might affect their children’s health. The second reason was the cost of immunization, which some of them could not afford to pay. However, the Health Department expressed a favorable attitude to the checking scheme. Though the Education Department agreed that the scheme was essential, they worried that it would affect the enrollment rate.Conclusion In spite of the difficulty in administering immunization certificate check, the effort would be rewarding for raising the immunization coverage rate among the children in Guizhou Province.
基金financially support by the National Key Research & Development Program of China (2016YFC0503200)the Natural Science Foundation of China (31760623)the Financial Project of State Forestry Administration (V2130211)
文摘Mating behavior and parturition are important components in the life history of any species. The endangered Chinese crocodile lizard(Shinisaurus crocodilurus) is suffering dramatic population decreases in the wild. Successful captive breeding can provide individuals to be reintroduced into their natural habitat and help to restore the wild populations. Studying the mating behavior and parturition of these lizards in captivity will enable us understand how is this ancient species reproduction and optimize artificial reproduction protocol. We studied the mating behavior and parturition of Chinese crocodile lizards in captivity using video recordings at the Daguishan National Nature Reserve, China, from 2015 to 2017. We analyzed pre-copulation and copulation, which occurred in mid-March to late May from all studied years. Pre-copulation and copulation lasted on average 7.51(n=11) and 27.45(n=11) minutes, respectively. We found that large-bodied male lizards have longer copulation periods, a pattern seen in other lizard species. In the mating event, males always initiated sex, while the females were passive. The duration of parturition lasted 153.8 ± 26.8(n=46) minutes, and larger females had heavier clutches. In addition, even though Chinese crocodile lizards represent an ancient lizard clade with primitive characteristics, they still abide by the reproduction patterns seen in most other lizard species.
文摘The DNA content and morphometric features of hepatocellular carcinoma (HCC) and liver cell dysplasia (LCD), including nuclear area, nuclear perimeter, nuclear maximum diameter and nuclear circle diameter, were quantitatively determined by means of image analysis technology. The results showed that in comparison with normal hepatocytes, LCD had a markedly increased DNA content and nuclear morphometric parameters, but the values were lower than those for HCC. LCD showed a slight increase in nuclear atypia represented by the nuclear irregular index, which was also less than HCC. The findings indicate that LCD may be a precaneerous lesion of HCC, to the cells in an abnormal proliferative state.
基金This work was supported by the funding from the National Natural Science Foundation of China(41825001 and 41991251)the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(2019QZKK0601).
文摘Charcoal is commonly preserved in both natural and artificial sediments,and is intensively used in paleontological,paleoenvironmental,and archaeological studies due to the abundant bio-information it contains.The biochemical properties of charcoal are also used for paleoclimatic reconstruction;however,the reliability of this approach has been challenged due to a lack of clarity on how physicochemical properties change during the charring process,as well as the temperatures required for charcoalification.To address this lack,in this study,Qinghai spruce and Chinese pine wood samples from the northeastern Tibetan Plateau were heated at different temperatures and for different lengths of time under restricted oxygen conditions.The reflectance;carbon,nitrogen,and oxygen content;and tracheid morphology were quantified before and after heating to assess changes related to the charring process.Archaeological charcoal remains were then evaluated to determine the charcoalification temperatures by comparing with the experimental results.The minimum temperature required for wood charcoalification was∼300℃,while temperatures recorded by archaeological charcoal were concentrated at 400-500℃.During the charring experiments,the tracheid cell walls gradually homogenized,and tracheid cell wall thickness and lumen area decreased by∼20%.On average,50%mass losses were observed;the carbon and oxygen content(%wt.)approximately changed from 47%to 60%and 48%to 35%respectively,while the nitrogen content(%wt.)fluctuated around 0.2%.The reflectance increased slightly from 0%to 0.5%.We propose that the charcoalification of wood tissue refers to charring(in restricted air)and carbonization(in the almost absence of air)when the wood is exposed to a heat source,which then finally transforms into a black,inert solid.This quantitative study provided valuable data and a thorough assessment of the process of wood charcoalification,as well as accurately estimated the feasibility of using charcoal physicochemical properties in paleoclimatic research.
文摘The literature illustrates the important issue of physician adherence to guidelines in their daily practice. In a quantitative study, we asked a random sample of 100 hospital gastroenterologists to evaluate their knowledge of guidelines and awareness of promoters. The degree to which guidelines were considered reliable was not related to the scientific evidence but was significantly associated with the promoter. The French Society of Gastroenterology was considered to be a more reliable promoter than national health agencies and pharmaceutical industries. Gastroenterologists become aware of guidelines mainly through their specialty society (62%). Specialty societies appear to be a more important source of information on guidelines for physicians. National health agencies should involve the specialty societies in the guideline development process to achieve changes in clinical practice.
基金Guangdong provincial medical science and technology research funding project(No.A2017250)Chinese and western medicine for knee osteoarthritis
文摘Objective:The effect of ankle rehabilitation robot on joint movement of hemiplegic patients was studied and quantitatively evaluated.Methods 90 hemiplegic patients with lower limb dysfunction treated in our hospital from April 2017 to March 2019 were selected as subjects.The patients were randomly divided into two groups:control group(n=45)and observation group(n=45).The patients in the two groups received language training,physiotherapy,exercise therapy,spa,occupational therapy,massage and other comprehensive rehabilitation treatment,on the basis of which the observation group received the auxiliary intervention of ankle rehabilitation robot.The soft tissue compliance of the patients was evaluated by ankle metatarsal flexion moment before and after treatment,the metatarsal flexor tension was evaluated by modified Tardieu scale,and the clinical effect was evaluated by ankle active ankle dorsiflexion.Results After treatment,the ankle flexion angles(0°,10°,20°,30°)in the two groups were significantly lower than those in the control group(P<0.05).Results compared with before treatment,the ankle flexion angles(0°,10°,20°,30°)in the two groups were significantly lower than those in the control group(P<0.05).After treatment,the angle of R1 and R2 measured by modified Tardieu scale of ankle plantar flexor group increased significantly,and the difference of R2-R1 decreased significantly(P<0.05).The improvement degree of the observation group was significantly better than that of the control group(P<0.05).After treatment,the active ankle extension activity of the two groups was significantly higher than that before treatment(P<0.05),and the effective rate of the observation group was significantly higher than that of the observation group(P<0.05).Conclusion Auxiliary intervention with ankle rehabilitation robot system can effectively improve the compliance of ankle soft tissue in spastic hemiplegia,reduce the contracture of metatarsal flexor muscle and improve the disturbance of joint movement in a short time.At the same time,the degree of coordination and acceptance of patients and their families is high,which is an effective means to improve the therapeutic effect.
