Objective To compare the characteristics of suicides in the four main demographic groups: urban males, urban females, rural males and rural females in order to help clarify the demographic pattern of suicides in Chin...Objective To compare the characteristics of suicides in the four main demographic groups: urban males, urban females, rural males and rural females in order to help clarify the demographic pattern of suicides in China. Methods A detailed psychological autopsy survey instrument was independently administered to 895 suicide victims in family members and close associates from 23 geographically representative locations from around the country. Results Pesticide ingestion accounted for 58% (519) of all suicides and 61% (3181519) of deaths were due to unsuccessful medical resuscitation. A substantial proportion (37%) of suicide victims did not have a mental illness. Among the 563 victims with mental illness, only 13% (76/563) received psychiatric treatment. Compared to other demographic groups, young rural females who died from suicide had the highest rate of pesticide ingestion (79%), the lowest prevalence of mental illness (39%), and the highest acute stress from precipitating life events just prior to the suicide. Contusion Many suicides in China are impulsive acts of deliberate self-harm following acute interpersonal crises. Prevention of suicides in China must focus on improving awareness of psychological problems, improving mental health services, providing alternative social support networks for managing acute interpersonal conflicts, limiting access to pesticides, and improving the resuscitation skills of primary care providers.展开更多
We describe a new BVRI multicolor CCD photometric system situated at the prime focus of the 85-cm telescope at the Xinglong Station of NAOC. Atmospheric extinction effects, photometric accuracy and color calibration d...We describe a new BVRI multicolor CCD photometric system situated at the prime focus of the 85-cm telescope at the Xinglong Station of NAOC. Atmospheric extinction effects, photometric accuracy and color calibration dependence of the system are investigated. Additional attention was paid to giving observers guidance in estimating throughput, detection limit, signal-to-noise ratio and exposure time.展开更多
Tobacco smoking is considered to be one of the main risk factors in the development of chronic pain.Long-term chronic exposure to nicotine and other forms of tobacco have been shown to be associated with an increased ...Tobacco smoking is considered to be one of the main risk factors in the development of chronic pain.Long-term chronic exposure to nicotine and other forms of tobacco have been shown to be associated with an increased incidence of pain.Studies have shown that acupuncture can help smokers to reduce their desire to smoke,reduce their withdrawal symptoms,and avoid a relapse after treatment.However,little has been reported about the effects of acupuncture on pain sensitivity caused by long-term smoking.Models of hyperalgesia were established in rats exposed to nicotine for 6 weeks.After 6 weeks of continuous nicotine exposure,electroacupuncture at bilateral acupoints Zusanli(ST36)and Taichong(LR3)was performed 20 minutes per day for 6 days at a continuous wave with a frequency of 2 Hz and a stimulus intensity of 1 m A.The results revealed that electroacupuncture treatment increased the mechanical response threshold of hind paw of nicotine-dependent rats with hyperalgesia and up-regulated the protein expression of pain-related factorsμ-opioid receptor,β-endorphin and glutamic acid decarboxylase 65 in the spinal cord and midbrain periaqueductal gray and the protein expression of glutamic acid decarboxylase 67 in the spinal cord.These findings suggest that electroacupuncture treatment has positive analgesic effects on pain sensitivity caused by long-term chronic nicotine exposure.One possible mechanism for the improved analgesia is that electroacupuncture increases the expression of painrelated factors in the spinal cord and midbrain periaqueductal gray.This study was approved by Institutional Animal Care and Use Committee(IACUC)of the University of Miami(#18-167)on December 12,2018.展开更多
Pitch is one of the most important auditory perception characteristics of sound; however, the mechanism underlying the pitch perception of sound is unclear. Although theoretical researches have suggested that percepti...Pitch is one of the most important auditory perception characteristics of sound; however, the mechanism underlying the pitch perception of sound is unclear. Although theoretical researches have suggested that perception of virtual pitch is connected with physics in cochlea of inner ear, there is no direct experimental observation of virtual pitch processing in the cochlea. By laser interferometry, we observe shift phenomena of virtual pitch in basilar membrane vibration of exsomatized cochlea, which is consistent with perceptual pitch shift observed in psychoacoustic experiments. This means that the complex mechanical vibration of basilar membrane in cochlea plays an important role in pitch information processing during hearing.展开更多
In this study,a novel safety integrity level(SIL)determination methodology of safety instrumented systems(SISs)with parameter uncertainty is proposed by combining multistage dynamic Bayesian networks(DBNs)and Monte Ca...In this study,a novel safety integrity level(SIL)determination methodology of safety instrumented systems(SISs)with parameter uncertainty is proposed by combining multistage dynamic Bayesian networks(DBNs)and Monte Carlo simulation.A multistage DBN model for SIL determination with multiple redundant cells is established.The models of function inspection test interval and function inspection test stages are alternately connected to form the multistage DBNs.The redundant cells can have different M out of N voting system architectures.An automatic modeling of conditional probability between nodes is developed.The SIL determination of SISs with parameter uncertainty is constructed by using the multistage DBNs and Monte Carlo simulation.A high-pressure SIS in the export of oil wellplatform is adopted to demonstrate the application of the proposed approach.The SIL and availability of the SIS and its subsystems are obtained.The influence of single subsystem on the SIL and availability of the SIS is studied.The influence of single redundant element on the SIL and availability of the subsystem is analyzed.A user-friendly SIL determination software with parameter uncertainty is developed on MATLAB graphical user interface.展开更多
Pitch is the most important auditory perception characteristic of sound with respect to speech intelligibility and music appreciation,and corresponds to a frequency of sound stimulus.However,in some cases,we can perce...Pitch is the most important auditory perception characteristic of sound with respect to speech intelligibility and music appreciation,and corresponds to a frequency of sound stimulus.However,in some cases,we can perceive virtual pitch,where the corresponding frequency component does not exist in the stimulating sound.This virtual pitch contains a deviation from the de Boer pitch shift formula,which is known as second pitch shift.It has been theoretically suggested that nonlinear dynamics in the cochlea or in the neural network produce a nonlinear resonance with a frequency corresponding to the virtual pitch;however,there is no direct experimental observation to support this theory.The second virtual pitch shift,expressed via basilar membrane nonlinear vibration temporal patterns,and consistent with psychoacoustic experiments,is observed in situ in the cochlea via laser interferometry.展开更多
The casting-solid extrusion forging plus semi-solid partial remelting route is used to improve the properties of AZ31 magnesium alloy products.The effect of remelting temperature and holding time on the microstructure...The casting-solid extrusion forging plus semi-solid partial remelting route is used to improve the properties of AZ31 magnesium alloy products.The effect of remelting temperature and holding time on the microstructure of AZ31 magnesium alloy is studied.Furthermore,the properties of AZ31 magnesium alloy components produced by the casting-solid extru.sion forging plus partial remelting route are examined.The results show that the AZ31 components have very good smooth surface and are formed completely.The increases in holding time and remelting temperature result in the formation of spheroidal grains surrounded by liquid phases.The best combination of properties of thixoforged alloy is290 MPa of tensile strength,220 MPa of yield strength and 10%of percentage elongation.展开更多
Objective:To investigate the therapeutic effects of Jiangan Xiaozhi decoction on nonalcoholic steatohepatitis(NASH)mice model and its effects on the endoplasmic reticulum stress(ERS)signaling pathway.Methods:NASH mice...Objective:To investigate the therapeutic effects of Jiangan Xiaozhi decoction on nonalcoholic steatohepatitis(NASH)mice model and its effects on the endoplasmic reticulum stress(ERS)signaling pathway.Methods:NASH mice model was established by methionine-choline deficient(MCD)diet induction and intragastric administration of Jiangan Xiaozhi decoction.The therapeutic effects of the decoction on NASH mice model were evaluated by measuring the body weight,hepatic index,and blood lipids and analyzing liver function-related biochemical markers,liver hematoxylin and eosin staining,and liver oil red O staining after the administration of the decoction in the mice model.Next,the levels of glucose-regulated protein 78(GRP78),inositol-requiring enzyme 1(IRE1),and X-box binding protein 1(XBP1)in the liver tissue of the mice were measured using Western blotting to investigate the mechanism underlying the treatment of NASH mice model by Jiangan Xiaozhi decoction.Results:Jiangan Xiaozhi decoction improved the body weight and hepatic index;reduced the levels of total cholesterol,transglutaminase,alanine transaminase,and aspartate aminotransferase;and improved pathological changes caused by hepatocyte necrosis,inflammatory cell infiltration,ballooning,and fat accumulation in the liver tissue of NASH mice model.The Western blot results showed that Jiangan Xiaozhi decoction reduced the levels of GRP78,IRE1,and XBP1 proteins in the liver tissues of NASH mice model.Conclusion:Jiangan Xiaozhi decoction has therapeutic effects on NASH mice model.The mechanism of its action may be related to the regulation of level of GRP78,IRE1,and XBP1 proteins in liver tissue and improvement of ERS.展开更多
Background Brucellosis is a severe zoonotic disease that is often overlooked, particularly in impoverished countries. Timely identification of focal complications in brucellosis is crucial for improving treatment outc...Background Brucellosis is a severe zoonotic disease that is often overlooked, particularly in impoverished countries. Timely identification of focal complications in brucellosis is crucial for improving treatment outcomes. However, there is currently a lack of established indicators or biomarkers for diagnosing these complications. Therefore, this study aimed to investigate potential warning signs of focal complications in human brucellosis, with the goal of providing practical parameters for clinicians to aid in the diagnosis and management of patients.Methods A multi-center cross-sectional study was conducted in China from December 2019 to August 2021. The study aimed to investigate the clinical characteristics and complications of patients with brucellosis using a questionnaire survey and medical record system. The presence of warning signs for complications was assessed using univariate and multivariate logistic regression models. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used for variable screening and model evaluation.Results A total of 880 participants diagnosed with human brucellosis were enrolled. The median age of the patients was 50 years [interquartile range (IQR): 41.5-58.0], and 54.8% had complications. The most common organ system affected by complications was the osteoarticular system (43.1%), with peripheral arthritis (30.0%), spondylitis (16.6%), paravertebral abscess (5.0%), and sacroiliitis (2.7%) being the most prevalent. Complications in other organ systems included the genitourinary system (4.7%), respiratory system (4.7%), and hematologic system (4.6%). Several factors were found to be associated with focal brucellosis. These factors included a long delay in diagnosis [odds ratio (OR) = 3.963, 95% confidence interval(CI): 1.906-8.238 for > 90 days], the presence of underlying disease (OR = 1.675, 95%CI: 1.176-2.384), arthralgia (OR = 3.197, 95%CI: 1.986-5.148), eye bulging pain (OR = 3.482, 95%CI: 1.349-8.988), C-reactive protein (CRP) > 10 mg/L (OR = 1.910, 95%CI: 1.310-2.784) and erythrocyte sedimentation rate (ESR) elevation (OR = 1.663, 95%CI: 1.145-2.415). The optimal cutoff value in ROC analysis was > 5.4 mg/L for CRP (sensitivity 73.4% and specificity 51.9%) and > 25 mm/h for ESR (sensitivity 47.9% and specificity 71.1%).Conclusions More than 50% of patients with brucellosis experienced complications. Factors such as diagnostic delay, underlying disease, arthralgia, eye pain, and elevated levels of CRP and ESR were identified as significant markers for the development of complications. Therefore, patients presenting with these conditions should be closely monitored for potential complications, regardless of their culture results and standard tube agglutination test titers.展开更多
Background: Acute fatty liver of pregnancy (AFLP) is a rare but life-threatening complication occurring in the third trimester. It is often fatal to both mother and fetus. The complicated clinical manifestations as...Background: Acute fatty liver of pregnancy (AFLP) is a rare but life-threatening complication occurring in the third trimester. It is often fatal to both mother and fetus. The complicated clinical manifestations as well as an insufficient understanding of the disease make the precise diagnosis and effective treatment of AF LP challenging. A full understanding of the risk factors, clinical features, and test findings of AFLP is critical for its timely diagnosis and treatment. Methods: We performed a retrospective study of 56 patients with AFLP between June 2008 and July 2013. We analyzed the clinical features, laboratory results, perioperative management, and patient outcomes. Results: The initial symptoms varied considerably, with nausea and vomiting (13/56, 23%) being the most common. Liver-function indexes were remarkable, including elevated levels of serum alanine aminotransferase (262.16 ± 281.71 U/L), aspartate aminotransferase (260.98 ± 237.91 U/L), lactic dehydrogenase (1011.76 ± 530.34 U/L), and direct bilirubin (85.59 ± 90.02 μmol/L). Coagulation disorders were indicated by abnormal levels offibrinogen (245.95 ± 186.11 mg/dL), D-dimer (2.46 ±4.01 mg/L), and fibrin degradation products (43.62 ±48.71 mg/L). The main maternal complications were hypoproteinemia (75%), coagulopathy (54%), and acute renal failure (39%). Multivariate logistic regression analysis identified prothrombin time (PT; odds ratio [OR] = 1.558, 95% confidence interval [CI] =1.248-1.946, P= 0.016) and international normalized ratio (INR; OR = 40.034, 95% CI= 2.517-636.693, P = 0.009) as risk factors. The perinatal infant death rate was related to gestational age at delivery (OR = 1.298, 95% CI- 1.040-1.618, P = 0.021), direct bilirubin (OR = 1.05, 95% CI = 1.008 1.094, P = 0.020), and fibrin degradation products (OR - 0.973, 95% CI = 0.950 0.996, P= 0.021). Conclusions: Nausea and vomiting may be the most common symptoms of AFLP. Indexes of liver dysfunction and coagulation disorders should also be considered. PT and INR are risk factors for fatal complications in patients with AFLP, and perinatal mortality is linked to the level of fibrin degradation products. Timely delivery is crucial to controlling the development of AFLR展开更多
Background:Considering the widespread of coronavirus disease 2019(COVID-19)pandemic in the world,it is important to understand the spatiotemporal development of the pandemic.In this study,we aimed to visualize time-as...Background:Considering the widespread of coronavirus disease 2019(COVID-19)pandemic in the world,it is important to understand the spatiotemporal development of the pandemic.In this study,we aimed to visualize time-associated alterations of COVID-19 in the context of continents and countries.展开更多
A series of nickel complexes{4 a:[(2,6-iPr2C6H3)N=CHC16H12O]Ni(Me)(Py),4b:[(2,6-iPr2C6H2OCH3)N=CHC16H12O]-Ni(Me)(Py),4 c:[(2,6-iPr2C6H2Cl)N=CHC16H12O]Ni(Me)(Py),and 4d:[(2,6-iPr2C6H2CF3)N=CHC16H12O]Ni(Me)(Py)}based on...A series of nickel complexes{4 a:[(2,6-iPr2C6H3)N=CHC16H12O]Ni(Me)(Py),4b:[(2,6-iPr2C6H2OCH3)N=CHC16H12O]-Ni(Me)(Py),4 c:[(2,6-iPr2C6H2Cl)N=CHC16H12O]Ni(Me)(Py),and 4d:[(2,6-iPr2C6H2CF3)N=CHC16H12O]Ni(Me)(Py)}based onβ-ketiminato ligands bearing various electron-donating or electron-withdrawing substituents on the para-position of the aniline group were synthesized and unambiguously characterized.The X-ray crystallographic analysis showed that complexes 4 b and 4 d adopted a nearsquare-planar geometry,and the anilines bearing a para-OMe or―CF3 group were found to situate on the axial position of the metal center.All complexes exhibited high activities up to 1.25×10^7–1.35×10^7 g PNB·molNi^–1·h^–1 toward norbornene(NBE)addition polymerization(conversion>91.2%in 2 min)under low loading of B(C6F5)3(B/Ni=3)at 30°C,affording polymers with high molecular weight up to 2.54×10^6–3.18×10^6.Different levels of decrease in catalytic activities could be observed for all catalysts as the reaction temperature increased;4 d bearing a strong electron-withdrawing―CF3 group showed the highest activity at 70°C,while others exhibited notable decrease in catalytic activity with the raise in reaction temperature.Complexes 4 a–4 d showed remarkable tolerance to polar groups and could efficiently promote the copolymerization of NBE with its polar derivatives,including NBE bearing small acetate and hydroxyl group,as well as bulky oligomers,yielding copolymers with high functional NBE incorporations.Novel NBE copolymers with high functional comonomer incorporations and improved solubility were obtained in high yields.展开更多
Melastomataceae has abundant morphological diversity with high economic and ornamental merit in Myrtales. The phylogenetic position of Myrtales is still contested. Here, we report the chromosome-level genome assembly ...Melastomataceae has abundant morphological diversity with high economic and ornamental merit in Myrtales. The phylogenetic position of Myrtales is still contested. Here, we report the chromosome-level genome assembly of Melastoma dodecandrum in Melastomataceae. The assembled genome size is299.81 Mb with a contig N50 value of 3.00 Mb. Genome evolution analysis indicated that M. dodecandrum,Eucalyptus grandis, and Punica granatum were clustered into a clade of Myrtales and formed a sister group with the ancestor of fabids and malvids. We found that M. dodecandrum experienced four whole-genome polyploidization events: the ancient event was shared with most eudicots, one event was shared with Myrtales, and the other two events were unique to M. dodecandrum. Moreover, we identified MADS-box genes and found that the AP1-like genes expanded, and AP3-like genes might have undergone subfunctionalization. The SUAR63-like genes and AG-like genes showed different expression patterns in stamens, which may be associated with heteranthery. In addition, we found that LAZY1-like genes were involved in the negative regulation of stem branching development, which may be related to its creeping features. Our study sheds new light on the evolution of Melastomataceae and Myrtales, which provides a comprehensive genetic resource for future research.展开更多
A catalyst system of Sevelamer, a phosphate-binding drug, has been prepared and used in the Knoevenagel reaction of aromatic aldehydes in water to produce substituted electrophilic alkenes. The products were obtained ...A catalyst system of Sevelamer, a phosphate-binding drug, has been prepared and used in the Knoevenagel reaction of aromatic aldehydes in water to produce substituted electrophilic alkenes. The products were obtained in excellent yields. Several novel, related catalytic systems showed promising catalytic properties for aromatic and heterocyclic aldehydes. The Sevelamer catalyst can be recovered using simple filtration and reused numerous times(up to 15 times) in the aqueous Knoevenagel reaction without any significant lowering of activity.展开更多
In this work, the optimal clathration condition was investigated for the preparation of aspirin-β-cyclodextrin (Asp-β-CD) inclusion complex using design of experiment (DOE) methodology. A 3-level, 3-factor Box-B...In this work, the optimal clathration condition was investigated for the preparation of aspirin-β-cyclodextrin (Asp-β-CD) inclusion complex using design of experiment (DOE) methodology. A 3-level, 3-factor Box-Behnken design with a total of 17 experimental runs was used. The Asp-β-CD inclusion complex was prepared by saturated solution method. The influence on the embedding rate was investigated, including molar ratio of β-CD to Asp, clathration temperature and clathration time, and the optimum values of such three test variables were found to be 0.82, 49C and 2.0 h, respectively. The embedding rate could be up to 61.19%. The formation of the bonding between -COOH group of Asp and O-H group of β-CD might play an important role in the process of clathration according to FT-IR spectra. Release kinetics of Asp from inclusion complex was studied for the evaluation of drug release mechanism and diffusion coefficients. The results showed that the drug release from matrix occurred through Fickian diffusion mechanism. The cumulative release of Asp reached only 40% over 24 h, so the inclusion complex could potentially be applied as a long-acting delivery system.展开更多
基金This project was supported by grants from the Ford Foundation, the Save the Children Fund, and Befrienders International.
文摘Objective To compare the characteristics of suicides in the four main demographic groups: urban males, urban females, rural males and rural females in order to help clarify the demographic pattern of suicides in China. Methods A detailed psychological autopsy survey instrument was independently administered to 895 suicide victims in family members and close associates from 23 geographically representative locations from around the country. Results Pesticide ingestion accounted for 58% (519) of all suicides and 61% (3181519) of deaths were due to unsuccessful medical resuscitation. A substantial proportion (37%) of suicide victims did not have a mental illness. Among the 563 victims with mental illness, only 13% (76/563) received psychiatric treatment. Compared to other demographic groups, young rural females who died from suicide had the highest rate of pesticide ingestion (79%), the lowest prevalence of mental illness (39%), and the highest acute stress from precipitating life events just prior to the suicide. Contusion Many suicides in China are impulsive acts of deliberate self-harm following acute interpersonal crises. Prevention of suicides in China must focus on improving awareness of psychological problems, improving mental health services, providing alternative social support networks for managing acute interpersonal conflicts, limiting access to pesticides, and improving the resuscitation skills of primary care providers.
基金Supported by the National Natural Science Foundation of China.
文摘We describe a new BVRI multicolor CCD photometric system situated at the prime focus of the 85-cm telescope at the Xinglong Station of NAOC. Atmospheric extinction effects, photometric accuracy and color calibration dependence of the system are investigated. Additional attention was paid to giving observers guidance in estimating throughput, detection limit, signal-to-noise ratio and exposure time.
基金supported by a grant from Department of Anesthesiology,Perioperative Medicine and Pain Management,University of Miami Miller School of Medicine,USA。
文摘Tobacco smoking is considered to be one of the main risk factors in the development of chronic pain.Long-term chronic exposure to nicotine and other forms of tobacco have been shown to be associated with an increased incidence of pain.Studies have shown that acupuncture can help smokers to reduce their desire to smoke,reduce their withdrawal symptoms,and avoid a relapse after treatment.However,little has been reported about the effects of acupuncture on pain sensitivity caused by long-term smoking.Models of hyperalgesia were established in rats exposed to nicotine for 6 weeks.After 6 weeks of continuous nicotine exposure,electroacupuncture at bilateral acupoints Zusanli(ST36)and Taichong(LR3)was performed 20 minutes per day for 6 days at a continuous wave with a frequency of 2 Hz and a stimulus intensity of 1 m A.The results revealed that electroacupuncture treatment increased the mechanical response threshold of hind paw of nicotine-dependent rats with hyperalgesia and up-regulated the protein expression of pain-related factorsμ-opioid receptor,β-endorphin and glutamic acid decarboxylase 65 in the spinal cord and midbrain periaqueductal gray and the protein expression of glutamic acid decarboxylase 67 in the spinal cord.These findings suggest that electroacupuncture treatment has positive analgesic effects on pain sensitivity caused by long-term chronic nicotine exposure.One possible mechanism for the improved analgesia is that electroacupuncture increases the expression of painrelated factors in the spinal cord and midbrain periaqueductal gray.This study was approved by Institutional Animal Care and Use Committee(IACUC)of the University of Miami(#18-167)on December 12,2018.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11374118 and 90820001
文摘Pitch is one of the most important auditory perception characteristics of sound; however, the mechanism underlying the pitch perception of sound is unclear. Although theoretical researches have suggested that perception of virtual pitch is connected with physics in cochlea of inner ear, there is no direct experimental observation of virtual pitch processing in the cochlea. By laser interferometry, we observe shift phenomena of virtual pitch in basilar membrane vibration of exsomatized cochlea, which is consistent with perceptual pitch shift observed in psychoacoustic experiments. This means that the complex mechanical vibration of basilar membrane in cochlea plays an important role in pitch information processing during hearing.
基金supported by the National Natural Science Foundation of China(No.52171287,No.51779267,No.51707204)the National Key Research and Development Program of China(No.2019YFE0105100)+3 种基金the IKTPLUSS program of Research Council of Norway(No.309628)the Taishan Scholars Project(No.tsqn201909063)the Fundamental Research Funds for the Central Universities,that is,the Opening Fund of National Engineering Laboratory of Offshore Geophysical and Exploration Equipment(No.20CX02301A)the Science and Technology Support Plan for Youth Innovation of Universities in Shandong Province(No.2019KJB016)。
文摘In this study,a novel safety integrity level(SIL)determination methodology of safety instrumented systems(SISs)with parameter uncertainty is proposed by combining multistage dynamic Bayesian networks(DBNs)and Monte Carlo simulation.A multistage DBN model for SIL determination with multiple redundant cells is established.The models of function inspection test interval and function inspection test stages are alternately connected to form the multistage DBNs.The redundant cells can have different M out of N voting system architectures.An automatic modeling of conditional probability between nodes is developed.The SIL determination of SISs with parameter uncertainty is constructed by using the multistage DBNs and Monte Carlo simulation.A high-pressure SIS in the export of oil wellplatform is adopted to demonstrate the application of the proposed approach.The SIL and availability of the SIS and its subsystems are obtained.The influence of single subsystem on the SIL and availability of the SIS is studied.The influence of single redundant element on the SIL and availability of the subsystem is analyzed.A user-friendly SIL determination software with parameter uncertainty is developed on MATLAB graphical user interface.
基金Supported by the National Natural Science Foundation of China(Grant Nos.11374118 and 90820001)。
文摘Pitch is the most important auditory perception characteristic of sound with respect to speech intelligibility and music appreciation,and corresponds to a frequency of sound stimulus.However,in some cases,we can perceive virtual pitch,where the corresponding frequency component does not exist in the stimulating sound.This virtual pitch contains a deviation from the de Boer pitch shift formula,which is known as second pitch shift.It has been theoretically suggested that nonlinear dynamics in the cochlea or in the neural network produce a nonlinear resonance with a frequency corresponding to the virtual pitch;however,there is no direct experimental observation to support this theory.The second virtual pitch shift,expressed via basilar membrane nonlinear vibration temporal patterns,and consistent with psychoacoustic experiments,is observed in situ in the cochlea via laser interferometry.
文摘The casting-solid extrusion forging plus semi-solid partial remelting route is used to improve the properties of AZ31 magnesium alloy products.The effect of remelting temperature and holding time on the microstructure of AZ31 magnesium alloy is studied.Furthermore,the properties of AZ31 magnesium alloy components produced by the casting-solid extru.sion forging plus partial remelting route are examined.The results show that the AZ31 components have very good smooth surface and are formed completely.The increases in holding time and remelting temperature result in the formation of spheroidal grains surrounded by liquid phases.The best combination of properties of thixoforged alloy is290 MPa of tensile strength,220 MPa of yield strength and 10%of percentage elongation.
文摘Objective:To investigate the therapeutic effects of Jiangan Xiaozhi decoction on nonalcoholic steatohepatitis(NASH)mice model and its effects on the endoplasmic reticulum stress(ERS)signaling pathway.Methods:NASH mice model was established by methionine-choline deficient(MCD)diet induction and intragastric administration of Jiangan Xiaozhi decoction.The therapeutic effects of the decoction on NASH mice model were evaluated by measuring the body weight,hepatic index,and blood lipids and analyzing liver function-related biochemical markers,liver hematoxylin and eosin staining,and liver oil red O staining after the administration of the decoction in the mice model.Next,the levels of glucose-regulated protein 78(GRP78),inositol-requiring enzyme 1(IRE1),and X-box binding protein 1(XBP1)in the liver tissue of the mice were measured using Western blotting to investigate the mechanism underlying the treatment of NASH mice model by Jiangan Xiaozhi decoction.Results:Jiangan Xiaozhi decoction improved the body weight and hepatic index;reduced the levels of total cholesterol,transglutaminase,alanine transaminase,and aspartate aminotransferase;and improved pathological changes caused by hepatocyte necrosis,inflammatory cell infiltration,ballooning,and fat accumulation in the liver tissue of NASH mice model.The Western blot results showed that Jiangan Xiaozhi decoction reduced the levels of GRP78,IRE1,and XBP1 proteins in the liver tissues of NASH mice model.Conclusion:Jiangan Xiaozhi decoction has therapeutic effects on NASH mice model.The mechanism of its action may be related to the regulation of level of GRP78,IRE1,and XBP1 proteins in liver tissue and improvement of ERS.
基金The study received support from the Public Health Emergency Response Mechanism Operation Program(102393220020010000017).
文摘Background Brucellosis is a severe zoonotic disease that is often overlooked, particularly in impoverished countries. Timely identification of focal complications in brucellosis is crucial for improving treatment outcomes. However, there is currently a lack of established indicators or biomarkers for diagnosing these complications. Therefore, this study aimed to investigate potential warning signs of focal complications in human brucellosis, with the goal of providing practical parameters for clinicians to aid in the diagnosis and management of patients.Methods A multi-center cross-sectional study was conducted in China from December 2019 to August 2021. The study aimed to investigate the clinical characteristics and complications of patients with brucellosis using a questionnaire survey and medical record system. The presence of warning signs for complications was assessed using univariate and multivariate logistic regression models. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used for variable screening and model evaluation.Results A total of 880 participants diagnosed with human brucellosis were enrolled. The median age of the patients was 50 years [interquartile range (IQR): 41.5-58.0], and 54.8% had complications. The most common organ system affected by complications was the osteoarticular system (43.1%), with peripheral arthritis (30.0%), spondylitis (16.6%), paravertebral abscess (5.0%), and sacroiliitis (2.7%) being the most prevalent. Complications in other organ systems included the genitourinary system (4.7%), respiratory system (4.7%), and hematologic system (4.6%). Several factors were found to be associated with focal brucellosis. These factors included a long delay in diagnosis [odds ratio (OR) = 3.963, 95% confidence interval(CI): 1.906-8.238 for > 90 days], the presence of underlying disease (OR = 1.675, 95%CI: 1.176-2.384), arthralgia (OR = 3.197, 95%CI: 1.986-5.148), eye bulging pain (OR = 3.482, 95%CI: 1.349-8.988), C-reactive protein (CRP) > 10 mg/L (OR = 1.910, 95%CI: 1.310-2.784) and erythrocyte sedimentation rate (ESR) elevation (OR = 1.663, 95%CI: 1.145-2.415). The optimal cutoff value in ROC analysis was > 5.4 mg/L for CRP (sensitivity 73.4% and specificity 51.9%) and > 25 mm/h for ESR (sensitivity 47.9% and specificity 71.1%).Conclusions More than 50% of patients with brucellosis experienced complications. Factors such as diagnostic delay, underlying disease, arthralgia, eye pain, and elevated levels of CRP and ESR were identified as significant markers for the development of complications. Therefore, patients presenting with these conditions should be closely monitored for potential complications, regardless of their culture results and standard tube agglutination test titers.
文摘Background: Acute fatty liver of pregnancy (AFLP) is a rare but life-threatening complication occurring in the third trimester. It is often fatal to both mother and fetus. The complicated clinical manifestations as well as an insufficient understanding of the disease make the precise diagnosis and effective treatment of AF LP challenging. A full understanding of the risk factors, clinical features, and test findings of AFLP is critical for its timely diagnosis and treatment. Methods: We performed a retrospective study of 56 patients with AFLP between June 2008 and July 2013. We analyzed the clinical features, laboratory results, perioperative management, and patient outcomes. Results: The initial symptoms varied considerably, with nausea and vomiting (13/56, 23%) being the most common. Liver-function indexes were remarkable, including elevated levels of serum alanine aminotransferase (262.16 ± 281.71 U/L), aspartate aminotransferase (260.98 ± 237.91 U/L), lactic dehydrogenase (1011.76 ± 530.34 U/L), and direct bilirubin (85.59 ± 90.02 μmol/L). Coagulation disorders were indicated by abnormal levels offibrinogen (245.95 ± 186.11 mg/dL), D-dimer (2.46 ±4.01 mg/L), and fibrin degradation products (43.62 ±48.71 mg/L). The main maternal complications were hypoproteinemia (75%), coagulopathy (54%), and acute renal failure (39%). Multivariate logistic regression analysis identified prothrombin time (PT; odds ratio [OR] = 1.558, 95% confidence interval [CI] =1.248-1.946, P= 0.016) and international normalized ratio (INR; OR = 40.034, 95% CI= 2.517-636.693, P = 0.009) as risk factors. The perinatal infant death rate was related to gestational age at delivery (OR = 1.298, 95% CI- 1.040-1.618, P = 0.021), direct bilirubin (OR = 1.05, 95% CI = 1.008 1.094, P = 0.020), and fibrin degradation products (OR - 0.973, 95% CI = 0.950 0.996, P= 0.021). Conclusions: Nausea and vomiting may be the most common symptoms of AFLP. Indexes of liver dysfunction and coagulation disorders should also be considered. PT and INR are risk factors for fatal complications in patients with AFLP, and perinatal mortality is linked to the level of fibrin degradation products. Timely delivery is crucial to controlling the development of AFLR
文摘Background:Considering the widespread of coronavirus disease 2019(COVID-19)pandemic in the world,it is important to understand the spatiotemporal development of the pandemic.In this study,we aimed to visualize time-associated alterations of COVID-19 in the context of continents and countries.
基金financially supported by the National Natural Science Foundation of China (Nos. 21574097 and 21690071)
文摘A series of nickel complexes{4 a:[(2,6-iPr2C6H3)N=CHC16H12O]Ni(Me)(Py),4b:[(2,6-iPr2C6H2OCH3)N=CHC16H12O]-Ni(Me)(Py),4 c:[(2,6-iPr2C6H2Cl)N=CHC16H12O]Ni(Me)(Py),and 4d:[(2,6-iPr2C6H2CF3)N=CHC16H12O]Ni(Me)(Py)}based onβ-ketiminato ligands bearing various electron-donating or electron-withdrawing substituents on the para-position of the aniline group were synthesized and unambiguously characterized.The X-ray crystallographic analysis showed that complexes 4 b and 4 d adopted a nearsquare-planar geometry,and the anilines bearing a para-OMe or―CF3 group were found to situate on the axial position of the metal center.All complexes exhibited high activities up to 1.25×10^7–1.35×10^7 g PNB·molNi^–1·h^–1 toward norbornene(NBE)addition polymerization(conversion>91.2%in 2 min)under low loading of B(C6F5)3(B/Ni=3)at 30°C,affording polymers with high molecular weight up to 2.54×10^6–3.18×10^6.Different levels of decrease in catalytic activities could be observed for all catalysts as the reaction temperature increased;4 d bearing a strong electron-withdrawing―CF3 group showed the highest activity at 70°C,while others exhibited notable decrease in catalytic activity with the raise in reaction temperature.Complexes 4 a–4 d showed remarkable tolerance to polar groups and could efficiently promote the copolymerization of NBE with its polar derivatives,including NBE bearing small acetate and hydroxyl group,as well as bulky oligomers,yielding copolymers with high functional NBE incorporations.Novel NBE copolymers with high functional comonomer incorporations and improved solubility were obtained in high yields.
基金supports from The Innovation and Application Engineering Technology Research Center of Ornamental Plant Germplasm Resources in Fujian Province (115-PTJH16005)The Plateau Discipline Construction Program of Fujian Province (115712018010)Special Fund for Forest Scientific Research in the Public Welfare (201204604)。
文摘Melastomataceae has abundant morphological diversity with high economic and ornamental merit in Myrtales. The phylogenetic position of Myrtales is still contested. Here, we report the chromosome-level genome assembly of Melastoma dodecandrum in Melastomataceae. The assembled genome size is299.81 Mb with a contig N50 value of 3.00 Mb. Genome evolution analysis indicated that M. dodecandrum,Eucalyptus grandis, and Punica granatum were clustered into a clade of Myrtales and formed a sister group with the ancestor of fabids and malvids. We found that M. dodecandrum experienced four whole-genome polyploidization events: the ancient event was shared with most eudicots, one event was shared with Myrtales, and the other two events were unique to M. dodecandrum. Moreover, we identified MADS-box genes and found that the AP1-like genes expanded, and AP3-like genes might have undergone subfunctionalization. The SUAR63-like genes and AG-like genes showed different expression patterns in stamens, which may be associated with heteranthery. In addition, we found that LAZY1-like genes were involved in the negative regulation of stem branching development, which may be related to its creeping features. Our study sheds new light on the evolution of Melastomataceae and Myrtales, which provides a comprehensive genetic resource for future research.
基金financial support by the National Natural Science Foundation of China (Nos. 21242004, 21302168)
文摘A catalyst system of Sevelamer, a phosphate-binding drug, has been prepared and used in the Knoevenagel reaction of aromatic aldehydes in water to produce substituted electrophilic alkenes. The products were obtained in excellent yields. Several novel, related catalytic systems showed promising catalytic properties for aromatic and heterocyclic aldehydes. The Sevelamer catalyst can be recovered using simple filtration and reused numerous times(up to 15 times) in the aqueous Knoevenagel reaction without any significant lowering of activity.
文摘In this work, the optimal clathration condition was investigated for the preparation of aspirin-β-cyclodextrin (Asp-β-CD) inclusion complex using design of experiment (DOE) methodology. A 3-level, 3-factor Box-Behnken design with a total of 17 experimental runs was used. The Asp-β-CD inclusion complex was prepared by saturated solution method. The influence on the embedding rate was investigated, including molar ratio of β-CD to Asp, clathration temperature and clathration time, and the optimum values of such three test variables were found to be 0.82, 49C and 2.0 h, respectively. The embedding rate could be up to 61.19%. The formation of the bonding between -COOH group of Asp and O-H group of β-CD might play an important role in the process of clathration according to FT-IR spectra. Release kinetics of Asp from inclusion complex was studied for the evaluation of drug release mechanism and diffusion coefficients. The results showed that the drug release from matrix occurred through Fickian diffusion mechanism. The cumulative release of Asp reached only 40% over 24 h, so the inclusion complex could potentially be applied as a long-acting delivery system.