The generalized inversion of S-wave amplitude spectra from the free-field strong motion recordings of the China National Strong Motion Observation Network System (NSMONS) are used to evaluate the site effects in the...The generalized inversion of S-wave amplitude spectra from the free-field strong motion recordings of the China National Strong Motion Observation Network System (NSMONS) are used to evaluate the site effects in the Wenchuan area. In this regard, a total of 602 recordings from 96 aftershocks of the Wenchuan earthquake with magnitudes of M3.7-M6.5 were selected as a dataset. These recordings were obtained from 28 stations at a hypocenter distance ranging from 30 km to 150 km. The inversion results have been verified as reliable by comparing the site response at station 62WUD using the Generalized Inversion Technique (GIT) and the Standard Spectral Ratio method (SSR). For all 28 stations, the site predominant frequency F and the average site amplification in different frequency bands of 1.0-5.0 Hz, 5.0-10.0 Hz and 1.0-10.0 Hz have been calculated based on the inversion results. Compared with the results from the horizontal-to-vertical spectral ratio (HVSR) method, it shows that the HVSR method can reasonably estimate the site predominant frequency but underestimates the site amplification. The linear fitting between the average site amplification for each frequency band and the V20 (the average uppermost-20 m shear wave velocity) shows good correlation. A distance measurement called the asperity distance DAspt is proposed to reasonably characterize the source-to-site distance for large earthquakes. Finally, the inversed site response is used to identify the soil nonlinearity in the main shock and aftershocks of Wenchuan earthquake. In ten of the 28 stations analyzed in the main shock, the soil behaved nonlinearly, where the ground motion level is apparently beyond a threshold ofPGA 〉 300 cm/s^2 or PGV 〉 20 cm/s, and only one station coded 51SFB has evidence of soil nonlinear behavior in the aftershocks.展开更多
Objective: To evaluate the efficacy and safety of Tongxiening Granules(痛泻宁颗粒, TXNG) in the treatment of irritable bowel syndrome with predominant diarrhea(IBS-D). Methods: A randomized, double-blind, double-dummy...Objective: To evaluate the efficacy and safety of Tongxiening Granules(痛泻宁颗粒, TXNG) in the treatment of irritable bowel syndrome with predominant diarrhea(IBS-D). Methods: A randomized, double-blind, double-dummy, and positive paral el control ed clinical trial was conducted from October 2014 to March 2016. Total y 342 patients from 13 clinical centers were enrolled and randomly assigned(at the ratio of 1:1) to a treatment group(171 cases) and a control group(171 cases) by a random coding table. The patients in the treatment group were administered oral y with TXNG(5 g per time) combined with pinaverium bromide Tablet simulator(50 mg per time), 3 times per day. The patients in the control group were given TXNG simulator(5 g per time) combined with pinaverium bromide Tablets(50 mg per time), 3 times per day. The treatment course lasted for 6 weeks. The improvement of Irritable Bowel Syndrome Symptom Severity Score(IBS-SSS) was used to evaluate the primary outcome. Secondary outcomes included adequate relief(AR) rate, Irritable Bowel Syndrome-Quality of Life Questionnaire(IBS-QOL), Hamilton Anxiety Scale(HAMA), Hamilton Depression Scale(HAMD), and the recurrence rate at fol ow-ups. Safety indices including the adverse events(AEs) and related laboratory tests were evaluated. Results: Primary outcome: IBS-SSS at baseline, weeks 2, 4, 6 showed no statistical significance in both full analysis set(FAS) and per protocol set(PPS, P>0.05). After 6 weeks of treatment, the total effective rate of IBS-SSS scores in the treatment group(147/171, 86.0%) was higher than the control group(143/171, 83.6%) by FAS(P>0.05). In regard to secondary outcomes, after 6-week treatment, there was no significant difference in AR rate, total score of IBS-QOL, improvement of HAMD and HAMA total scores between the two groups(P>0.05). The recurrence rate at 8-week fol ow-up was 12.35%(10/18) in treatment group and 15.79%(12/76) in control group, respectivery(P>0.05). A total of 21 AEs occurred in 15 cases, of which 11 occurred in 8 cas展开更多
To develop uniform and seismic environment-dependent design spectrum,common acceleration response spectral characteristics need to be identified.In this paper,a bi-normalized response spectrum (BNRS) is proposed,which...To develop uniform and seismic environment-dependent design spectrum,common acceleration response spectral characteristics need to be identified.In this paper,a bi-normalized response spectrum (BNRS) is proposed,which is defined as a spectrum of peak response acceleration normalized with respect to peak acceleration of the excitation plotted vs.the natural period of the system normalized with respect to the spectrum predominant period,Tp.Based on a statistical analysis of records from the 1999 Chi-Chi earthquake,the conventionally normalized response spectrum(NRS) and the BNRS are examined to account for the effects of soil conditions,epicentral distance,hanging wall and damping.It is found that compared to the NRS the BNRS is much less dependent on these factors.Finally,some simple relationships between the BNRS for a specified damping ratio and that for a damping ratio of 5%,and between the spectra predominant period and epicentral distance for different soil types are provided.展开更多
Past researchers have anticipated the occurrence of a great earthquake in the central Himalayas in the near future.This may cause serious damage in the Kathmandu Valley,which sits on an ancient lake bed zone,with lacu...Past researchers have anticipated the occurrence of a great earthquake in the central Himalayas in the near future.This may cause serious damage in the Kathmandu Valley,which sits on an ancient lake bed zone,with lacustrine sediments of more than 500 m depth.In this study,the predominant frequency of ground motion is evaluated using the Horizontal-to-Vertical (H/V) spectral ratio technique and recordings of ambient noise.The results of the H/V ratio show two peaks in about 20 percent of the locations,which are distributed mainly in and around the center and northern part of the Kathmandu Valley.The predominant frequencies vary from 0.5 Hz to 8.9 Hz in the study area,whereas the second resonance fiequency varies from 4 Hz to 6 Hz in the center and northern part of the valley.This indicates that the center and northern part of the valley have a wide range of resonance frequency due to two levels of impedance contrast- one may be from the surface layer and the other may be from the layer undemeath.These two levels of resonance indicate the importance of considering the effects of surface and lower layers during the planning and designing of infrastructures in the Kathmandu Valley.展开更多
Symptomatic improvement of patients with functional dyspepsia after drug therapy is often incomplete and obtained in not more than 60% of patients. This is likely because functional dyspepsia is a heterogeneous diseas...Symptomatic improvement of patients with functional dyspepsia after drug therapy is often incomplete and obtained in not more than 60% of patients. This is likely because functional dyspepsia is a heterogeneous disease. Although great advance has been achieved with the consensus definitions of the Rome I and II criteria, there are still some aspects about the definition of functional dyspepsia that require clarification. The Rome criteria explicitly recognise that epigastric pain or discomfort must be the predominant complaint in patients labelled as suffering from functional dyspepsia. However, this strict definition can create problems in the daily primary care clinical practice, where the patient with functional dyspepsia presents with multiple symptoms. Before starting drug therapy it is recommended to provide the patient with an explanation of the disease process and reassurance. A thorough physical examination and judicious use of laboratory data and endoscopy are also indicated. In general, the approach to treat patients with functional dyspepsia based on their main symptom is practical and effective. Generally, patients should be treated with acid suppressive therapy using proton-pump inhibitors if the predominant symptoms are epigastric pain or gastroesophageal reflux symptoms. Although the role of Helicobacter pylori (H pylon) in functional dyspepsia continues to be a matter of debate, recent data indicate that there is modest but clear benefit of eradication of H pylori in patients with functional dyspepsia. In addition, H pylori is a gastric carcinogen and if found it should be eliminated. Although there are no specific diets for patients with FD, it may be helpful to guide the patients on healthy exercise and eating habits.展开更多
Pneumoconiosis,the predominant occupational disease in China and the world,is a pulmonary disease caused by the inhalation of inorganic dust,that is,particulate matter in the solid phase without living organisms[1].As...Pneumoconiosis,the predominant occupational disease in China and the world,is a pulmonary disease caused by the inhalation of inorganic dust,that is,particulate matter in the solid phase without living organisms[1].As an irreversible,crippling,and even fatal disease,pneumoconiosis places a heavy burden on society.展开更多
Background: Both Parkinson's disease (PD) and multiple system atrophy (MSA) have associated sleep disorders related to the underlying neurodegenerative pathology. Clinically, MSA with predominant parkinsonism (...Background: Both Parkinson's disease (PD) and multiple system atrophy (MSA) have associated sleep disorders related to the underlying neurodegenerative pathology. Clinically, MSA with predominant parkinsonism (MSA-P) resembles PD in the manifestation of prominent parkinsonism, Whether the amount of rapid eye movement (REM) sleep without atonia could be a potential marker for differentiating MSA-P from PD has not been thoroughly investigated. This study aimed to examine whether sleep parameters could provide a method for differentiating MSA-P from PD. Methods: This study comprised 24 MSA-P patients and 30 PD patients, and they were of similar age, gender, and REM sleep behavior disorder (RBD) prevalence. All patients underwent clinical evaluation and one night of video-polysomnography recording. The tonic and phasic chin electromyogram (EMG) activity was manually quantified during REM sleep of each patient. We divided both groups in terms of whether they had RBD to make subgroup analysis. Results: No significant difference between MSA-P group and PD group had been tbund in clinical characteristics and sleep architecture. However, MSA-P patients had higher apnea-hypopnea index (AHI; 1.15 [0.00, 8.73]/h vs. 0.00 [0.00, 0.55]/h, P = 0.024) and higher tonic chin EMG density (34.02 [ 18.48, 57.18]% vs. 8.40 [3.11, 13.061%, P 〈 0.001 ) as compared to PD patients. Subgroup analysis found that tonic EMG density in MSA + RBD subgroup was higher than that in PD + RBD subgroup (55.04 [26.81,69.62]% vs. 11.40 [8.51,20.411%, P 〈 0.001 ). Furthermore, no evidence of any difference in tonic EMG density emerged between PD + RBD and MSA - RBD subgroups (P 〉 0.05). Both disease duration (P = 0.056) and AHI (P = 0.051) showed no significant differences during subgroup analysis although there was a trend toward longer disease duration in PD + RBD subgroup and higher AHI in MSA - RBD subgroup. Stepwise multiple linear regression analysis identified the presence of M展开更多
In the clinic,the diagnosis of Parkinson’s disease(PD)largely depends on clinicians’experience.When the diagnosis is made,approximately 80%of dopaminergic cells in the substantia nigra(SN)have been lost.Additionally...In the clinic,the diagnosis of Parkinson’s disease(PD)largely depends on clinicians’experience.When the diagnosis is made,approximately 80%of dopaminergic cells in the substantia nigra(SN)have been lost.Additionally,it is rather challenging to differentiate PD from atypical parkinsonian disorders(APD).Clinially-available 3T conventional MRI contributes little to solve these problems.The pathologic alterations of parkinsonism show abnormal brain iron deposition,and therefore susceptibility-weighted imaging(SWI),which is sensitive to iron concentration,has been applied to find iron-related lesions for the diagnosis and differentiation of PD in recent decades.Until now,the majority of research has revealed that in SWI the signal intensity changes in deep brain nuclei,such as the SN,the putamen(PUT),the globus pallidus(GP),the thalamus(TH),the red nucleus(RN)and the caudate nucleus(CN),thereby raising the possibility of early diagnosis and differentiation.Furthermore,the signal changes in SN,PUT and TH sub-regions may settle the issues with higher accuracy.In this article,we review the brain iron deposition of PD,MSA-P and PSP in SWI in the hope of exhibiting a profile of SWI features in PD,MSA and PSP and its clinical values.展开更多
It is widely known that the seismic response characteristics of a soil site depends heavily on several key dynamic properties of the soil stratum,such as predominant frequency and damping ratio.A widely used method fo...It is widely known that the seismic response characteristics of a soil site depends heavily on several key dynamic properties of the soil stratum,such as predominant frequency and damping ratio.A widely used method for estimating the predominant frequency of a soil site by using microtremor records,proposed by Nakamura,is investigated to determine its effectiveness in estimating the damping ratio.The authors conducted some microtremor measurements of soil sites in Hong Kong and found that Nakamura's method might also be used to estimate the damping ratio of a soil site.Damping ratio data from several typical soil sites were obtained from both Nakamura's ratio curves using the half power point method and resonant column tests.Regression analysis indicates that there is a strong correlation between the damping ratios derived from these two different approaches.展开更多
On the basis of laboratory-scale-tests, the method of using immobilized biological activated carbon (IBAC) was found to be an efficient method to treat oil wastewater. In this research, pilot-scale studies were conduc...On the basis of laboratory-scale-tests, the method of using immobilized biological activated carbon (IBAC) was found to be an efficient method to treat oil wastewater. In this research, pilot-scale studies were conducted to investigate the optimal range of factors, such as oil concentration, and hydraulic retention time (HRT). 39 strains of bacteria were isolated from activated sludge of a petrochemical wastewater treatment plant. After being acclimated and identified, these bacteria were immobilized on granular activated carbon. The degradation of organic compounds was analyzed by gas chromatography-mass spectromtry (GC-MS). As the results show that when the oil concentration is lower than 50 mg/L and corresponding values of HRT are longer than 1.0 h, the removal rate of immobilized biological activated carbon column can stably reach at least 70%. In the field studies, electron microscope analyses show that the predominant bacteria have been changed from Pseudomonas and Bacillus at the beginning to Bacillus only after 60 days of continuous operation, which suggests that the method with immobilized biological activated carbon column is the one with higher efficiency than that of the secondary floatation tank traditionally used in oil wastewater treatment.展开更多
Reconnaissance reports and pertinent research on seismic hazards show that liquefaction is one of the key sources of damage to geotechnical and structural engineering systems. Therefore, identifying site liquefaction ...Reconnaissance reports and pertinent research on seismic hazards show that liquefaction is one of the key sources of damage to geotechnical and structural engineering systems. Therefore, identifying site liquefaction conditions plays an important role in seismic hazard mitigation. One of the widely used approaches for detecting liquefaction is based on the time-frequency analysis of ground motion recordings, in which short-time Fourier transform is typically used. It is known that recordings at a site with liquefaction are the result of nonlinear responses of seismic waves propagating in the liquefied layers underneath the site. Moreover, Fourier transform is not effective in characterizing such dynamic features as time-dependent frequency of the recordings rooted in nonlinear responses. Therefore, the aforementioned approach may not be intrinsically effective in detecting liquefaction. An alternative to the Fourier-based approach is presented in this study, which proposes time-frequency analysis of earthquake ground motion recordings with the aid of the Hilbert-Huang transform (HHT), and offers justification for the HHT in addressing the liquefaction features shown in the recordings. The paper then defines the predominant instantaneous frequency (PIF) and introduces the PiF-related motion features to identify liquefaction conditions at a given site. Analysis of 29 recorded data sets at different site conditions shows that the proposed approach is effective in detecting site liquefaction in comparison with other methods.展开更多
Summary What is already known about this topic?Anopheles sinensis(An.sinensis)is the predominant malaria vector in China.The impact of S-methoprene on the emergence process of mosquito larvae suggests its potential as...Summary What is already known about this topic?Anopheles sinensis(An.sinensis)is the predominant malaria vector in China.The impact of S-methoprene on the emergence process of mosquito larvae suggests its potential as a control method for vector mosquitoes.However,the efficacy of S-methoprene in controlling An.sinensis has not yet been demonstrated.What is added by this report?展开更多
The dynamic characteristics of ground soil using micro-tremor observation in Asia (Zushi and Ogasawara (Japan), Xi’an (China), Manila (Philippines), and Gujarat (India)) are studied. Ground micro-tremor signals were ...The dynamic characteristics of ground soil using micro-tremor observation in Asia (Zushi and Ogasawara (Japan), Xi’an (China), Manila (Philippines), and Gujarat (India)) are studied. Ground micro-tremor signals were observed and analyzed by fast Fourier transform method (FFT). The response of ground soil to frequency of ground micro-tremor is revealed, and func- tions with frequency-dependence and frequency-selection of micro-tremor for different foundation soil strata are also researched. The horizontal to vertical spectral ratio (H/V, Nakamura technique) of micro-tremor observed at the surface ground was used to evaluate the site’s predominant period. This paper also discusses the application of micro-tremor on site safety evaluation, and gives the observed calculation results obtained at multiple points. The experimental foundation and the deduction process of the method are described in detail. Some problems of the method are pointed out. Potential use of the technique’s good expandable nature makes it a useable means for preventing and reducing disaster’s harmful effects.展开更多
To determine the shear wave velocity structure and predominant period features of Tmaztepe in izmir, Turkey, where new building sites have been planned, active-passive surface wave methods and single-station microtrem...To determine the shear wave velocity structure and predominant period features of Tmaztepe in izmir, Turkey, where new building sites have been planned, active-passive surface wave methods and single-station microtremor measurements are used, as well as surface acquisition techniques, including the multichannel analysis of surface waves (MASW), refraction microtremor (ReMi), and the spatial autocorrelation method (SPAC), to pinpoint shallow and deep shear wave velocity. For engineering bedrock (V 〉 760 m/s) conditions at a depth of 30 m, an average seismic shear wave velocity in the upper 30 m of soil (AVs30) is not only accepted as an important parameter for defining ground behavior during earthquakes, but a primary parameter in the geotechnical analysis for areas to be classified by V30 according to the National Earthquake Hazards Reduction Program (NEHRP). It is also determined that Z1.0, which represents a depth to V = 1000 m/s, is used for ground motion prediction and changed from 0 to 54 m. The sediment-engineering bedrock structure for Tmaztepe that was obtained shows engineering bedrock no deeper than 30 m. When compared, the depth of engineering bedrock and dominant period map and geology are generally compatible.展开更多
For the first time, a nodulin-like gene promoter was isolated from Gossypium hirsutum L. Guo Y 18 by means of inverse PCR. Three plant expression vectors were constructed for functional identification of the promoter....For the first time, a nodulin-like gene promoter was isolated from Gossypium hirsutum L. Guo Y 18 by means of inverse PCR. Three plant expression vectors were constructed for functional identification of the promoter. These vectors were different only in promoter regions; three truncations of the nodulinlike promoter took the place of the CaMV35S promoter in the pBI 121 plant expression vector. Then, the three vectors were introduced into cotton plants via the pollen tube pathway. The expression patterns of the gus gene driven by nodulin-like promoter truncations were investigated in the offspring of transgenic cotton plants. Histochemical GUS staining and fluorescence quantitative analysis were performed to achieve this goal. The results showed that the nodulin-like promoter was a strong, highly reproductive organspecific promoter, which demonstrated a much higher driver activity than the CaMV35S promoter did in cotton reproductive organs, but relatively lower activity in vegetation. Identification of the speciality and strength-determining regions of the nodulin-like promoter was also undertaken.展开更多
Due to increasing life expectancy,the amount of people with dementia worldwide is expected to experience a substantial rise,with estimates indicating a growth from 55 million in 2019 to a staggering 139 million by the...Due to increasing life expectancy,the amount of people with dementia worldwide is expected to experience a substantial rise,with estimates indicating a growth from 55 million in 2019 to a staggering 139 million by the year 2050.Among the various forms of dementia.Alzheimer's disease(AD)stands out as the predominant and most prevalent.展开更多
To the Editor:Spinocerebellar ataxia type 3(SCA3)is the predominant subtype,representing 48-73%of all SCAs in the Chinese population.[1]It primarily manifests as progressive ataxia,characterized by unsteady gait,dysar...To the Editor:Spinocerebellar ataxia type 3(SCA3)is the predominant subtype,representing 48-73%of all SCAs in the Chinese population.[1]It primarily manifests as progressive ataxia,characterized by unsteady gait,dysarthria,and limb clumsiness,due to cerebellar and interconnected gray matter damage.Notably,extracerebellar features such as extrapyramidal and oculomotor abnormalities,and spasticity,often remain underrecognized.This complexity can lead to misdiagnosis,underscoring the necessity for a more comprehensive understanding of both cerebellar and extracerebellar symptoms.展开更多
Objective To observe the clinical efficacy and safety of Shuchang Decoction (SCD) in the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D)with Gan depression and Pi deficiency syndrome.Methods A total...Objective To observe the clinical efficacy and safety of Shuchang Decoction (SCD) in the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D)with Gan depression and Pi deficiency syndrome.Methods A total of 179 patients with IBS-D were recruited from 12 hospitals of Shanghai TCM Gastroenterology Federation.展开更多
基金Nonprofit Industry Research Project of CEA under Grant No. 201208014National Natural Science Fund No. 51278473Environmental Protection Research Fund for Public Interest No. 201209040
文摘The generalized inversion of S-wave amplitude spectra from the free-field strong motion recordings of the China National Strong Motion Observation Network System (NSMONS) are used to evaluate the site effects in the Wenchuan area. In this regard, a total of 602 recordings from 96 aftershocks of the Wenchuan earthquake with magnitudes of M3.7-M6.5 were selected as a dataset. These recordings were obtained from 28 stations at a hypocenter distance ranging from 30 km to 150 km. The inversion results have been verified as reliable by comparing the site response at station 62WUD using the Generalized Inversion Technique (GIT) and the Standard Spectral Ratio method (SSR). For all 28 stations, the site predominant frequency F and the average site amplification in different frequency bands of 1.0-5.0 Hz, 5.0-10.0 Hz and 1.0-10.0 Hz have been calculated based on the inversion results. Compared with the results from the horizontal-to-vertical spectral ratio (HVSR) method, it shows that the HVSR method can reasonably estimate the site predominant frequency but underestimates the site amplification. The linear fitting between the average site amplification for each frequency band and the V20 (the average uppermost-20 m shear wave velocity) shows good correlation. A distance measurement called the asperity distance DAspt is proposed to reasonably characterize the source-to-site distance for large earthquakes. Finally, the inversed site response is used to identify the soil nonlinearity in the main shock and aftershocks of Wenchuan earthquake. In ten of the 28 stations analyzed in the main shock, the soil behaved nonlinearly, where the ground motion level is apparently beyond a threshold ofPGA 〉 300 cm/s^2 or PGV 〉 20 cm/s, and only one station coded 51SFB has evidence of soil nonlinear behavior in the aftershocks.
文摘Objective: To evaluate the efficacy and safety of Tongxiening Granules(痛泻宁颗粒, TXNG) in the treatment of irritable bowel syndrome with predominant diarrhea(IBS-D). Methods: A randomized, double-blind, double-dummy, and positive paral el control ed clinical trial was conducted from October 2014 to March 2016. Total y 342 patients from 13 clinical centers were enrolled and randomly assigned(at the ratio of 1:1) to a treatment group(171 cases) and a control group(171 cases) by a random coding table. The patients in the treatment group were administered oral y with TXNG(5 g per time) combined with pinaverium bromide Tablet simulator(50 mg per time), 3 times per day. The patients in the control group were given TXNG simulator(5 g per time) combined with pinaverium bromide Tablets(50 mg per time), 3 times per day. The treatment course lasted for 6 weeks. The improvement of Irritable Bowel Syndrome Symptom Severity Score(IBS-SSS) was used to evaluate the primary outcome. Secondary outcomes included adequate relief(AR) rate, Irritable Bowel Syndrome-Quality of Life Questionnaire(IBS-QOL), Hamilton Anxiety Scale(HAMA), Hamilton Depression Scale(HAMD), and the recurrence rate at fol ow-ups. Safety indices including the adverse events(AEs) and related laboratory tests were evaluated. Results: Primary outcome: IBS-SSS at baseline, weeks 2, 4, 6 showed no statistical significance in both full analysis set(FAS) and per protocol set(PPS, P>0.05). After 6 weeks of treatment, the total effective rate of IBS-SSS scores in the treatment group(147/171, 86.0%) was higher than the control group(143/171, 83.6%) by FAS(P>0.05). In regard to secondary outcomes, after 6-week treatment, there was no significant difference in AR rate, total score of IBS-QOL, improvement of HAMD and HAMA total scores between the two groups(P>0.05). The recurrence rate at 8-week fol ow-up was 12.35%(10/18) in treatment group and 15.79%(12/76) in control group, respectivery(P>0.05). A total of 21 AEs occurred in 15 cases, of which 11 occurred in 8 cas
基金Heilongjiang Natural Science Foundation Under Project No.ZGJ03-03the Research Fund for the Doctoral Program of Higher Education of China Through Project No.20030213042
文摘To develop uniform and seismic environment-dependent design spectrum,common acceleration response spectral characteristics need to be identified.In this paper,a bi-normalized response spectrum (BNRS) is proposed,which is defined as a spectrum of peak response acceleration normalized with respect to peak acceleration of the excitation plotted vs.the natural period of the system normalized with respect to the spectrum predominant period,Tp.Based on a statistical analysis of records from the 1999 Chi-Chi earthquake,the conventionally normalized response spectrum(NRS) and the BNRS are examined to account for the effects of soil conditions,epicentral distance,hanging wall and damping.It is found that compared to the NRS the BNRS is much less dependent on these factors.Finally,some simple relationships between the BNRS for a specified damping ratio and that for a damping ratio of 5%,and between the spectra predominant period and epicentral distance for different soil types are provided.
文摘Past researchers have anticipated the occurrence of a great earthquake in the central Himalayas in the near future.This may cause serious damage in the Kathmandu Valley,which sits on an ancient lake bed zone,with lacustrine sediments of more than 500 m depth.In this study,the predominant frequency of ground motion is evaluated using the Horizontal-to-Vertical (H/V) spectral ratio technique and recordings of ambient noise.The results of the H/V ratio show two peaks in about 20 percent of the locations,which are distributed mainly in and around the center and northern part of the Kathmandu Valley.The predominant frequencies vary from 0.5 Hz to 8.9 Hz in the study area,whereas the second resonance fiequency varies from 4 Hz to 6 Hz in the center and northern part of the valley.This indicates that the center and northern part of the valley have a wide range of resonance frequency due to two levels of impedance contrast- one may be from the surface layer and the other may be from the layer undemeath.These two levels of resonance indicate the importance of considering the effects of surface and lower layers during the planning and designing of infrastructures in the Kathmandu Valley.
文摘Symptomatic improvement of patients with functional dyspepsia after drug therapy is often incomplete and obtained in not more than 60% of patients. This is likely because functional dyspepsia is a heterogeneous disease. Although great advance has been achieved with the consensus definitions of the Rome I and II criteria, there are still some aspects about the definition of functional dyspepsia that require clarification. The Rome criteria explicitly recognise that epigastric pain or discomfort must be the predominant complaint in patients labelled as suffering from functional dyspepsia. However, this strict definition can create problems in the daily primary care clinical practice, where the patient with functional dyspepsia presents with multiple symptoms. Before starting drug therapy it is recommended to provide the patient with an explanation of the disease process and reassurance. A thorough physical examination and judicious use of laboratory data and endoscopy are also indicated. In general, the approach to treat patients with functional dyspepsia based on their main symptom is practical and effective. Generally, patients should be treated with acid suppressive therapy using proton-pump inhibitors if the predominant symptoms are epigastric pain or gastroesophageal reflux symptoms. Although the role of Helicobacter pylori (H pylon) in functional dyspepsia continues to be a matter of debate, recent data indicate that there is modest but clear benefit of eradication of H pylori in patients with functional dyspepsia. In addition, H pylori is a gastric carcinogen and if found it should be eliminated. Although there are no specific diets for patients with FD, it may be helpful to guide the patients on healthy exercise and eating habits.
基金the National Natural Science Foundation of China:Molecular mechanism of 1-phosphosphingol and lysophosphatidic acid involved in silicosis[No:81641119]。
文摘Pneumoconiosis,the predominant occupational disease in China and the world,is a pulmonary disease caused by the inhalation of inorganic dust,that is,particulate matter in the solid phase without living organisms[1].As an irreversible,crippling,and even fatal disease,pneumoconiosis places a heavy burden on society.
文摘Background: Both Parkinson's disease (PD) and multiple system atrophy (MSA) have associated sleep disorders related to the underlying neurodegenerative pathology. Clinically, MSA with predominant parkinsonism (MSA-P) resembles PD in the manifestation of prominent parkinsonism, Whether the amount of rapid eye movement (REM) sleep without atonia could be a potential marker for differentiating MSA-P from PD has not been thoroughly investigated. This study aimed to examine whether sleep parameters could provide a method for differentiating MSA-P from PD. Methods: This study comprised 24 MSA-P patients and 30 PD patients, and they were of similar age, gender, and REM sleep behavior disorder (RBD) prevalence. All patients underwent clinical evaluation and one night of video-polysomnography recording. The tonic and phasic chin electromyogram (EMG) activity was manually quantified during REM sleep of each patient. We divided both groups in terms of whether they had RBD to make subgroup analysis. Results: No significant difference between MSA-P group and PD group had been tbund in clinical characteristics and sleep architecture. However, MSA-P patients had higher apnea-hypopnea index (AHI; 1.15 [0.00, 8.73]/h vs. 0.00 [0.00, 0.55]/h, P = 0.024) and higher tonic chin EMG density (34.02 [ 18.48, 57.18]% vs. 8.40 [3.11, 13.061%, P 〈 0.001 ) as compared to PD patients. Subgroup analysis found that tonic EMG density in MSA + RBD subgroup was higher than that in PD + RBD subgroup (55.04 [26.81,69.62]% vs. 11.40 [8.51,20.411%, P 〈 0.001 ). Furthermore, no evidence of any difference in tonic EMG density emerged between PD + RBD and MSA - RBD subgroups (P 〉 0.05). Both disease duration (P = 0.056) and AHI (P = 0.051) showed no significant differences during subgroup analysis although there was a trend toward longer disease duration in PD + RBD subgroup and higher AHI in MSA - RBD subgroup. Stepwise multiple linear regression analysis identified the presence of M
基金This work was funded by China National Nature Science Fund(No.81371421).
文摘In the clinic,the diagnosis of Parkinson’s disease(PD)largely depends on clinicians’experience.When the diagnosis is made,approximately 80%of dopaminergic cells in the substantia nigra(SN)have been lost.Additionally,it is rather challenging to differentiate PD from atypical parkinsonian disorders(APD).Clinially-available 3T conventional MRI contributes little to solve these problems.The pathologic alterations of parkinsonism show abnormal brain iron deposition,and therefore susceptibility-weighted imaging(SWI),which is sensitive to iron concentration,has been applied to find iron-related lesions for the diagnosis and differentiation of PD in recent decades.Until now,the majority of research has revealed that in SWI the signal intensity changes in deep brain nuclei,such as the SN,the putamen(PUT),the globus pallidus(GP),the thalamus(TH),the red nucleus(RN)and the caudate nucleus(CN),thereby raising the possibility of early diagnosis and differentiation.Furthermore,the signal changes in SN,PUT and TH sub-regions may settle the issues with higher accuracy.In this article,we review the brain iron deposition of PD,MSA-P and PSP in SWI in the hope of exhibiting a profile of SWI features in PD,MSA and PSP and its clinical values.
基金Research project (PolyU 5076/97E),of the Department of Civil and Structural Engineering,The Hong Kong Polytechnic University
文摘It is widely known that the seismic response characteristics of a soil site depends heavily on several key dynamic properties of the soil stratum,such as predominant frequency and damping ratio.A widely used method for estimating the predominant frequency of a soil site by using microtremor records,proposed by Nakamura,is investigated to determine its effectiveness in estimating the damping ratio.The authors conducted some microtremor measurements of soil sites in Hong Kong and found that Nakamura's method might also be used to estimate the damping ratio of a soil site.Damping ratio data from several typical soil sites were obtained from both Nakamura's ratio curves using the half power point method and resonant column tests.Regression analysis indicates that there is a strong correlation between the damping ratios derived from these two different approaches.
文摘On the basis of laboratory-scale-tests, the method of using immobilized biological activated carbon (IBAC) was found to be an efficient method to treat oil wastewater. In this research, pilot-scale studies were conducted to investigate the optimal range of factors, such as oil concentration, and hydraulic retention time (HRT). 39 strains of bacteria were isolated from activated sludge of a petrochemical wastewater treatment plant. After being acclimated and identified, these bacteria were immobilized on granular activated carbon. The degradation of organic compounds was analyzed by gas chromatography-mass spectromtry (GC-MS). As the results show that when the oil concentration is lower than 50 mg/L and corresponding values of HRT are longer than 1.0 h, the removal rate of immobilized biological activated carbon column can stably reach at least 70%. In the field studies, electron microscope analyses show that the predominant bacteria have been changed from Pseudomonas and Bacillus at the beginning to Bacillus only after 60 days of continuous operation, which suggests that the method with immobilized biological activated carbon column is the one with higher efficiency than that of the secondary floatation tank traditionally used in oil wastewater treatment.
基金National Natural Science Foundation of China Under Grant 50278090 the National Science Foundation of the USA with Grant Nos. 0085272 and 0414363 US-PRC Researcher Exchange Program administered by the MCEER
文摘Reconnaissance reports and pertinent research on seismic hazards show that liquefaction is one of the key sources of damage to geotechnical and structural engineering systems. Therefore, identifying site liquefaction conditions plays an important role in seismic hazard mitigation. One of the widely used approaches for detecting liquefaction is based on the time-frequency analysis of ground motion recordings, in which short-time Fourier transform is typically used. It is known that recordings at a site with liquefaction are the result of nonlinear responses of seismic waves propagating in the liquefied layers underneath the site. Moreover, Fourier transform is not effective in characterizing such dynamic features as time-dependent frequency of the recordings rooted in nonlinear responses. Therefore, the aforementioned approach may not be intrinsically effective in detecting liquefaction. An alternative to the Fourier-based approach is presented in this study, which proposes time-frequency analysis of earthquake ground motion recordings with the aid of the Hilbert-Huang transform (HHT), and offers justification for the HHT in addressing the liquefaction features shown in the recordings. The paper then defines the predominant instantaneous frequency (PIF) and introduces the PiF-related motion features to identify liquefaction conditions at a given site. Analysis of 29 recorded data sets at different site conditions shows that the proposed approach is effective in detecting site liquefaction in comparison with other methods.
基金Project on the Establishment of China-ASEAN Science and Technology Cooperation Center for Public Health(KY202101004)funded by The National Key Research and Development Program of China.
文摘Summary What is already known about this topic?Anopheles sinensis(An.sinensis)is the predominant malaria vector in China.The impact of S-methoprene on the emergence process of mosquito larvae suggests its potential as a control method for vector mosquitoes.However,the efficacy of S-methoprene in controlling An.sinensis has not yet been demonstrated.What is added by this report?
文摘The dynamic characteristics of ground soil using micro-tremor observation in Asia (Zushi and Ogasawara (Japan), Xi’an (China), Manila (Philippines), and Gujarat (India)) are studied. Ground micro-tremor signals were observed and analyzed by fast Fourier transform method (FFT). The response of ground soil to frequency of ground micro-tremor is revealed, and func- tions with frequency-dependence and frequency-selection of micro-tremor for different foundation soil strata are also researched. The horizontal to vertical spectral ratio (H/V, Nakamura technique) of micro-tremor observed at the surface ground was used to evaluate the site’s predominant period. This paper also discusses the application of micro-tremor on site safety evaluation, and gives the observed calculation results obtained at multiple points. The experimental foundation and the deduction process of the method are described in detail. Some problems of the method are pointed out. Potential use of the technique’s good expandable nature makes it a useable means for preventing and reducing disaster’s harmful effects.
文摘To determine the shear wave velocity structure and predominant period features of Tmaztepe in izmir, Turkey, where new building sites have been planned, active-passive surface wave methods and single-station microtremor measurements are used, as well as surface acquisition techniques, including the multichannel analysis of surface waves (MASW), refraction microtremor (ReMi), and the spatial autocorrelation method (SPAC), to pinpoint shallow and deep shear wave velocity. For engineering bedrock (V 〉 760 m/s) conditions at a depth of 30 m, an average seismic shear wave velocity in the upper 30 m of soil (AVs30) is not only accepted as an important parameter for defining ground behavior during earthquakes, but a primary parameter in the geotechnical analysis for areas to be classified by V30 according to the National Earthquake Hazards Reduction Program (NEHRP). It is also determined that Z1.0, which represents a depth to V = 1000 m/s, is used for ground motion prediction and changed from 0 to 54 m. The sediment-engineering bedrock structure for Tmaztepe that was obtained shows engineering bedrock no deeper than 30 m. When compared, the depth of engineering bedrock and dominant period map and geology are generally compatible.
基金国家高技术研究发展计划(863计划),the National Special Project for Cotton Development from Agricultural Department of the Chinese Government
文摘For the first time, a nodulin-like gene promoter was isolated from Gossypium hirsutum L. Guo Y 18 by means of inverse PCR. Three plant expression vectors were constructed for functional identification of the promoter. These vectors were different only in promoter regions; three truncations of the nodulinlike promoter took the place of the CaMV35S promoter in the pBI 121 plant expression vector. Then, the three vectors were introduced into cotton plants via the pollen tube pathway. The expression patterns of the gus gene driven by nodulin-like promoter truncations were investigated in the offspring of transgenic cotton plants. Histochemical GUS staining and fluorescence quantitative analysis were performed to achieve this goal. The results showed that the nodulin-like promoter was a strong, highly reproductive organspecific promoter, which demonstrated a much higher driver activity than the CaMV35S promoter did in cotton reproductive organs, but relatively lower activity in vegetation. Identification of the speciality and strength-determining regions of the nodulin-like promoter was also undertaken.
基金supported by grants PID2020-115823-GB100 funded by MCIN/AEI/10.13039/501100011033SBPLY/21/180501/000150 funded by JCCM/ERDF-A way of making Europe+1 种基金2022-GRIN-34354 grant by UCLM/ERDF intramural funding to LJD and JDNLMargarita Salas Postdoctoral Research Fellow (2021-MS-20549)funded by European Union NextGenerationEU/PRTR。
文摘Due to increasing life expectancy,the amount of people with dementia worldwide is expected to experience a substantial rise,with estimates indicating a growth from 55 million in 2019 to a staggering 139 million by the year 2050.Among the various forms of dementia.Alzheimer's disease(AD)stands out as the predominant and most prevalent.
基金supported by the National Natural Science Foundation of China to Zhiying Wu(Nos.82071260,82230062).
文摘To the Editor:Spinocerebellar ataxia type 3(SCA3)is the predominant subtype,representing 48-73%of all SCAs in the Chinese population.[1]It primarily manifests as progressive ataxia,characterized by unsteady gait,dysarthria,and limb clumsiness,due to cerebellar and interconnected gray matter damage.Notably,extracerebellar features such as extrapyramidal and oculomotor abnormalities,and spasticity,often remain underrecognized.This complexity can lead to misdiagnosis,underscoring the necessity for a more comprehensive understanding of both cerebellar and extracerebellar symptoms.
文摘Objective To observe the clinical efficacy and safety of Shuchang Decoction (SCD) in the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D)with Gan depression and Pi deficiency syndrome.Methods A total of 179 patients with IBS-D were recruited from 12 hospitals of Shanghai TCM Gastroenterology Federation.