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SIMULTANEOUS DETERMINATION OF NEODYMIUM AND PRASEODYMIUM BY ZERO-ORDER AND FOURTH-ORDER DFRIVATIVE SPECTROPHOTOMETRY
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作者 Nai Xing Wang Department of Applied Chemistry,Shandong University,Jinan,250100,Shandong,People’s Repulic of China 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第1期41-44,共4页
With derivative spectrophotometric method,the complexes of lanthanides with 2-(5-bromo-2-pyridylazo)-5-diethylaminophen- ol(5-Br-PADAP)in the presence of octylphenol poly(ethyleneg- lycol)ether(TX-100)were studied.It ... With derivative spectrophotometric method,the complexes of lanthanides with 2-(5-bromo-2-pyridylazo)-5-diethylaminophen- ol(5-Br-PADAP)in the presence of octylphenol poly(ethyleneg- lycol)ether(TX-100)were studied.It is found that the maximum absorption of fourth-order derivative spectra of the neodymium complex by 4f electron transitions is at 579(+)nm and 582(-)nm with molar derivative absorptivities of 5.2×10~3 1.mol^(-1).cm^(-1). The maximum absorption of the zero-order derivative spectra of the complexes for neodymium and praseodymium is at 580hm,the molar absorptivities are 1.47×10~5 l.mol^(-1).cm^(-1)for Nd and 1.26 ×10~5 l.mol^(-1).cm^(-1)for Pr.The component ratio of the complex is Nd:5-Br-PADAP=1:4.Beer's law is obeyed in the range of 0-3.75μg of Nd and Pr in 25ml of solution.The method has been used for the simultaneous determination of Nd and Pr in four synthetic samples and the results obtained are satisfactory. 展开更多
关键词 der SIMULTANEOUS DEtermINATION OF NEODYMIUM AND PRASEODYMIUM BY zero-order AND FOURTH-ORDER DFRIVATIVE SPECTROPHOTOMETRY
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Method for eliminating zero-order image in digital holography
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作者 刘雯雯 康新 +1 位作者 戴宜全 何小元 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期113-116,共4页
For eliminating the zero-order image in digital holography, a new method using the differential of the hologram intensity instead of the hologram itself for numerical reconstruction is proposed. This method is based o... For eliminating the zero-order image in digital holography, a new method using the differential of the hologram intensity instead of the hologram itself for numerical reconstruction is proposed. This method is based on digital image processing. By analyzing the spatial spectrum of the off-axis digital hologram, it theoretically proves that the zero-order image can be effectively eliminated by differential before reconstruction. Then, the detected hologram is processed in the program with differential and reconstruction. Both the theoretical analysis and digital reconstruction results show that it can effectively eliminate the large bright spot in the center of the reconstructed image caused by the zero-order image, improve the image quality significantly, and render a better contrast of the reconstructed image. This method is very simple and convenient due to no superfluous optical elements and requiring only one time record. 展开更多
关键词 digital holography zero-order image digital image processing Fresnel integral
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Axial acoustic radiation force on an elastic spherical shell near an impedance boundary for zero-order quasi-Bessel-Gauss beam 被引量:3
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作者 Yu-Chen Zang Wei-Jun Lin +1 位作者 Chang Su Peng-Fei Wu 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期305-318,共14页
Shell structures have increasingly widespread applications in biomedical ultrasound fields such as contrast agents and drug delivery,which requires the precise prediction of the acoustic radiation force under various ... Shell structures have increasingly widespread applications in biomedical ultrasound fields such as contrast agents and drug delivery,which requires the precise prediction of the acoustic radiation force under various circumstances to improve the system efficiency.The acoustic radiation force exerted by a zero-order quasi-Bessel-Gauss beam on an elastic spherical shell near an impedance boundary is theoretically and numerically studied in this study.By means of the finite series method and the image theory,a zero-order quasi-Bessel-Gauss beam is expanded in terms of spherical harmonic functions,and the exact solution of the acoustic radiation force is derived based on the acoustic scattering theory.The acoustic radiation force function,which represents the radiation force per unit energy density and per unit cross-sectional surface,is especially investigated.Some simulated results for a polymethyl methacrylate shell and an aluminum shell are provided to illustrate the behavior of acoustic radiation force in this case.The simulated results show the oscillatory property and the negative radiation force caused by the impedance boundary.An appropriate relative thickness of the shell can generate sharp peaks for a polymethyl methacrylate shell.Strong radiation force can be obtained at small half-cone angles and the beam waist only affects the results at high frequencies.Considering that the quasi-Bessel-Gauss beam possesses both the energy focusing property and the non-diffracting advantage,this study is expected to be useful in the development of acoustic tweezers,contrast agent micro-shells,and drug delivery applications. 展开更多
关键词 acoustic radiation force zero-order quasi-Bessel-Gauss beam impedance boundary elastic spherical shell
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Improved Grid Relaxation with Zero-Order Integrators
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作者 Jan Mueller Hans-Georg Matuttis 《Journal of Applied Mathematics and Physics》 2021年第6期1257-1270,共14页
In this research, we have improved a relaxation method for triangular meshes intended for finite element fluid simulations which contain discrete element particles. The triangle edges are treated as springs which rela... In this research, we have improved a relaxation method for triangular meshes intended for finite element fluid simulations which contain discrete element particles. The triangle edges are treated as springs which relax their lengths towards a “better” force equilibrium where the triangles are closer to equilateral shape. The actual kernel is an improved zero order integrator which is able to follow reconfigurations of the particles faster than earlier methods. The improved relaxation allows larger timesteps in the flow simulation and leads to more stable, faster mesh reconfigurations for fast moving particles in the flow. Additionally, this demonstrates how integrators of the same order zero can nevertheless have different convergence speeds towards 展开更多
关键词 zero-order Solver EQUILIBRATION Grid Generation Fluid Mechanics
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Profile of Full-Term Births in Maternity Wards of Public Hospitals in Douala Cameroon
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作者 Henri Essome Merlin Boten Bounyom +14 位作者 Astrid Ndolo Kondo Ingrid Doriane Ofakem Ilick Fulbert Mangala Nkwele Irène Cyrielle Edjoa Mboe Michel Roger Ekono Alphonse Ngalame Nyong Robert Tchounzou Moustapha Bilkissou Junie Ngaha Yaneu Marga Vanina Ngono Akam Gervais Mounchikpou Ngouhouo Grâce Tocki Toutou Théophile Nana Njamen Valère Mve Koh Pascal Foumane 《Open Journal of Obstetrics and Gynecology》 2024年第5期705-720,共16页
Introduction: Pregnancy as much as childbirth constitutes a risky situation, potentially fraught with sometimes dramatic complications: maternal death. Objective: We conducted this study with the aim of establishing t... Introduction: Pregnancy as much as childbirth constitutes a risky situation, potentially fraught with sometimes dramatic complications: maternal death. Objective: We conducted this study with the aim of establishing the profile of those giving birth in our context with the aim to anticipate operationally in the future on morbidity but more on maternal deaths. Methodology: We conducted, using a structured questionnaire, a prospective descriptive study in representative maternity wards in the city of Douala;the study variables were socio-economic, anthropometric, obstetrical and clinical. Statistical analyses were carried out with CS Pro 7.3 and SPSS version 25.0 software. The Student, Chi-square and Fischer tests were used to compare the means of the variables and the percentages. Results: We recruited 305 births for our study. The average age of our births was 28.7 years ± 6.1 with an average height of 161.6 cm ± 5.06;an average body mass index at the start of pregnancy of 28.0 kilograms/square meter and 31.3 kilograms/square meter at delivery;the average weight gain was 8.4 g ± 5.37;an average gestation of 2.84±1.90;an average parity of 2.2 ± 2.1 with an average birth interval of 27.7 months ± 23.7. The average gestational age was 39.2 weeks ± 1.21 with pregnancy pathology dominated by malaria;85.9% began their prenatal follow-up before the 14th week of amenorrhea. Conclusion: The profile of childbirth in urban Cameroon does not seem potentially dystocic compared to that of the same regional and racial area. 展开更多
关键词 PROFILE Delivery term MALARIA Douala
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A Comparison between Late Preterm and Term Infants with Respiratory Distress Syndrome, Early-Onset Sepsis, and Neonatal Jaundice in Ecuadorian Newborns
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作者 Teresa Altamirano Molina 《Open Journal of Pediatrics》 2024年第1期22-35,共14页
Background: To examine the differences in prevalence of respiratory distress syndrome, early-onset sepsis and jaundice, between late preterm infants versus term infants in Ecuadorian newborns. Methods: Study design: E... Background: To examine the differences in prevalence of respiratory distress syndrome, early-onset sepsis and jaundice, between late preterm infants versus term infants in Ecuadorian newborns. Methods: Study design: Epidemiological, observational, and cross-sectional, with two cohorts of patients. Settings: IESS Quito Sur Hospital at Quito, Ecuador, from February to April of 2020. Participants: This study included 204 newborns, 102 preterm infants, 102 term infants. Results: There are significant differences between late preterm infants and term infants, with a p-value of 0.000 in the prevalence of early sepsis, 70.59% vs. 35.29%. In respiratory distress syndrome between late and term premature infants, significant differences were observed with a p-value of 0.000, the proportion being 55.58% vs. 24.51% respectively. The prevalence of jaundice is higher in term infants with a p value of 0.002, 72.55%, versus 51.96% in late preterm infants, and the mean value of bilirubins in mg/dL was higher in term infants 14.32 versus 12.33 in late preterm infants;this difference is statistically significant with a p value of 0.004. Admission to the NICU is more frequent in late preterm infants with a p-value of 0.000, being 42.16% for late preterm infants vs. 7.84% in term infants;the mean of the hospital days with p-value 0.005, was higher in late preterm infants 4.97 days vs. 3.55 days for term newborns. Conclusion: Due to the conditions of their immaturity, late preterm infants are 2.86 times more likely to present early sepsis than full-term newborns. It is shown that late preterm infants are 2.69 times more likely to have respiratory distress syndrome compared to term infants, therefore, late preterm infants have a longer hospital stay of 4.97 days versus 3.55 days in term infants. Jaundice and mean bilirubin levels are higher in term infants due to blood group incompatibility and insufficient breastfeeding. 展开更多
关键词 Late Preterm term Newborn Respiratory Distress Syndrome Early Onset Sepsis JAUNDICE
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Long-term assessment of collagenase treatment for Dupuytren’s contracture:A 10-year follow-up study
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作者 Marco Passiatore Vitale Cilli +4 位作者 Adriano Cannella Ludovico Caruso Giulia Maria Sassara Giuseppe Taccardo Rocco De Vitis 《World Journal of Orthopedics》 2024年第4期355-362,共8页
BACKGROUND Enzymatic fasciotomy with collagenase clostridium histolyticum(CCH)has revolutionized the treatment for Dupuytren’s contracture(DC).Despite its benefits,the long-term outcomes remain unclear.This study pre... BACKGROUND Enzymatic fasciotomy with collagenase clostridium histolyticum(CCH)has revolutionized the treatment for Dupuytren’s contracture(DC).Despite its benefits,the long-term outcomes remain unclear.This study presented a comprehensive 10-year follow-up assessment of the enduring effects of CCH on patients with DC.AIM To compare the short-term(12 wk)and long-term(10 years)outcomes on CCH treatment in patients with DC.METHODS A cohort of 45 patients was treated with CCH at the metacarpophalangeal(MCP)joint and the proximal interphalangeal(PIP)joint and underwent systematic reevaluation.The study adhered to multicenter trial protocols,and assessments were conducted at 12 wk,7 years,and 10 years post-surgery.RESULTS Thirty-seven patients completed the 10-year follow-up.At 10 years,patients treated at the PIP joint exhibited a 100%recurrence.However,patients treated at the MCP joint only showed a 50%recurrence.Patient satisfaction varied,with a lower satisfaction reported in PIP joint cases.Recurrence exceeding 20 degrees on the total passive extension deficit was observed,indicating a challenge for sustained efficacy.Significant differences were noted between outcomes at the 7-year and 10-year intervals.CONCLUSION CCH demonstrated sustained efficacy when applied to the MCP joint.However,caution is warranted for CCH treatment at the PIP joint due to a high level of recurrence and low patient satisfaction.Re-intervention is needed within a decade of treatment. 展开更多
关键词 COLLAGENASE Xiapex Dupuytren disease Dupuytren recurrence Long term follow-up
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Long-term outcomes of endoscopic submucosal dissection for undifferentiated type early gastric cancer over 2 cm with R0 resection
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作者 Jun Yong Bae Chang Beom Ryu +1 位作者 Moon Sung Lee Kulwinder S Dua 《World Journal of Gastrointestinal Endoscopy》 2024年第6期326-334,共9页
BACKGROUND Endoscopic submucosal dissection(ESD)for over 2 cm in size undifferentiated type(UD type)early gastric cancer(EGC)confined to the mucosa is not only challenging,but also long-term outcomes are not well know... BACKGROUND Endoscopic submucosal dissection(ESD)for over 2 cm in size undifferentiated type(UD type)early gastric cancer(EGC)confined to the mucosa is not only challenging,but also long-term outcomes are not well known.AIM To evaluate the long-term outcomes of ESD done for UD type EGCs confined to the mucosa over 2 cm in size and compare the results with those where the lesions were less than 2 cm.METHODS 143 patients with UD type EGC confirmed on histology after ESD at a tertiary hospital were reviewed.Cases with synchronous and metachronous lesions and a case with emergency surgery after ESD were excluded.A total of 137 cases were enrolled.79 cases who underwent R0 resection were divided into 2 cm or less(group A)and over 2 cm(group B)in size.RESULTS Among 79 patients who underwent R0 resection,the number in group A and B were 51 and 28,respectively.The mean follow-up period(SD)was 79.71±45.42 months.There was a local recurrence in group A(1/51,2%)and group B(1/28,3.6%)respectively.This patient in group A underwent surgery while the patient in group B underwent repeated ESD with no further recurrences in both patients.There was no regional lymph node metastasis,distant metastasis,and deaths in both groups.With R0 resection strategy for ESD on lesions over 2 cm,20.4%(28/137)of patients were able to avoid surgery compared with expanded indication.CONCLUSION If R0 resection is achieved by ESD,UD type EGCs over 2 cm also showed good and similar clinical outcomes as compared to lesions less than 2 cm when followed for over 5 years.With R0 resection strategy,several patients can avoid surgery. 展开更多
关键词 Undifferentiated type early gastric cancer Endoscopic submucosal dissection Long term outcomes Over 2 cm Early gastric cancer
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Draft of an Anthropometric Reference System for Full-Term Cameroonian Newborns: Prospective Study with Analytical Aim in the Maternity Wards of Douala
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作者 Henri Essome Charlotte Epossè Ekoube +16 位作者 Fulbert Mangala Nkwele Rita Carole Mbono Betoko Irène Cyrielle Edjoa Mboe Michel Roger Ekono Alphonse Ngalame Nyong Robert Tchounzou Ingrid Doriane Ofakem Ilick Hassanatou Iyawa Moustapha Bilkissou Astrid Ndolo Kondo Junie Ngaha Yaneu Marga Vanina Ngono Akam Gervais Mounchikpou Ngouhouo Grâce Tocki Toutou Nelly Noubi Valère Mve Koh Théophile Nana Njamen 《Open Journal of Obstetrics and Gynecology》 2024年第3期435-450,共16页
Introduction: Anthropometry applied to newborns is a reliable indicator of the quality of fetal growth. The latter is influenced by genetic, racial and nutritional factors varying from one population to another, expla... Introduction: Anthropometry applied to newborns is a reliable indicator of the quality of fetal growth. The latter is influenced by genetic, racial and nutritional factors varying from one population to another, explaining why a standard cannot be applied to all populations. Research question: should the Caucasian frame of reference be dogmatically applied in our African context? Multicenter studies are therefore necessary;hence the interest of this work, the main objective of which was to describe the anthropometric profile of full-term newborns in the city of Douala. Methodology: We carried out a cross-sectional study with an analytical aim and prospective data collection in the maternity wards of the Douala General Hospital, Laquintinie Hospital, District hospitals of Deido, Nylon and Bonassama over a period of 4 months (January to April 2020). We were interested in any newborn, born alive, vaginally or by cesarean section, seen in the first 24 hours from a full-term single-fetal pregnancy whose mother had given consent. We excluded newborns whose term was unclear and those with congenital malformations or signs of embryo-foetopathy. Data collection was done using structured and pre-tested survey sheets. The study variables were obstetric and anthropometric. Statistical analyzes were carried out with CS Pro 7.3 and SPSS version 25.0 software. The Student, Chi-square and Fischer tests were used to compare the means of the variables, the percentages with a significance threshold P value Results: During the study period, 305 full-term newborns were included, divided into 172 boys and 133 girls. The average anthropometric parameters of the full-term newborn in the city of Douala were: average weight: 3305 grams, average height: 49.8 centimeters, average head circumference: 34.6 centimeters, average upper arm circumference: 11.3 centimeters, circumference average thoracic: 32.8 centimeters. The percentile distribution showed a 10th percentile at 2656 grams and a 90th percentile at 3966 grams for weight defining the limits for small-for-gestational-age neonates and macrosomes. Conclusion: The anthropometric data of the full-term newborn in the city of Douala were: an average weight of 3305.4 grams, an average height of 49.8 centimeters, an average head circumference of 34.2 centimeters, an average upper arm circumference of 11.3 centimeters, and an average thoracic circumference of 32.8 centimeters with higher valuesin male newborns. 展开更多
关键词 ANTHROPOMETRY Full-term Newborn Douala
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Long-Term Mortality of Children with Congenital Heart Disease Admitted to the Departmental University Hospital of Borgou/Alibori from 2011 to 2022
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作者 Serge Hugues Mahougnon Dohou Nicolas Hamondji Amegan +3 位作者 Ahmad Ibrahim Gérard Médétinmè Kpanidja Chabi Olaniran Alphonse Biaou Houétondji Léopold Codjo 《World Journal of Cardiovascular Diseases》 CAS 2024年第3期166-186,共21页
Background: Congenital heart disease is a public health issue due to its incidence and mortality rate. The aim of this study was to investigate the long-term mortality of children with congenital heart disease admitte... Background: Congenital heart disease is a public health issue due to its incidence and mortality rate. The aim of this study was to investigate the long-term mortality of children with congenital heart disease admitted to the Departmental University Hospital of Borgou/Alibori (CHUD-B/A) from 2011 to 2022. Methods: This descriptive longitudinal study with analytical aims covered 11 years (April 1, 2011 to December 31, 2022). It consisted of a review of the records of children under 15 years of age with echocardiographically confirmed congenital heart disease. This was followed by an interview with the parents to assess the children’s current condition. Data were entered using Kobocollect software and analyzed using R Studio 4.2.2. software. Results: A total of 143 complete files were retained. The median age at diagnosis was 14 months (IIQ: Q1 = 4;Q3 = 60) with a range of 2 days and 175 months, and the sex-ratio (M/F) was 0.96. Left-to-right shunts were the most frequent cardiopathy group (62.9%). Only 35 children (24.5%) benefited from restorative treatment. The mortality rate was 31.5%. Median survival under the maximum bias assumption was 114 months and 216 months under the assumption of minimum bias. Survival was significantly better in children with right-to-left shunts (p = 0.0049) under the assumption of minimum bias. The death risk factors were: age at diagnosis less than 12 months (aHR = 7.58;95% CI = 3.36 - 17.24;p Conclusion: The long-term mortality of congenital heart disease is high and favoured by the absence of restorative treatment. Local correction of congenital heart disease and medical follow-up will help to reduce this mortality. 展开更多
关键词 Congenital Heart Disease LONG-term MORTALITY Parakou Risk Factors
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A Prospective Study on Evaluating the Long-Term Effects of Childhood Vaccination from Birth to 13 Years Old in Kuwait
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作者 Nedaa A. Al-Khamees 《Health》 2024年第10期932-969,共38页
Background: To prevent infectious diseases and deaths of children, vaccinations play a crucial role in public health strategies in Kuwait. However, it remained uncertain to demonstrate the potential long-term health o... Background: To prevent infectious diseases and deaths of children, vaccinations play a crucial role in public health strategies in Kuwait. However, it remained uncertain to demonstrate the potential long-term health outcomes of vaccination, including neurodevelopmental disorders (NDD) and autism. This study aimed to evaluate the long-term health outcomes of vaccination among Kuwait children from birth to thirteen years old. Objectives: This study included the significant objectives: (1) to compare long-term health effects, including chronic and acute conditions for unvaccinated, partially vaccinated, and vaccinated children, and (2) to evaluate the association of vaccination with the neurodevelopmental disorders (NDD) and autism, and the preventable illnesses. Methods: This prospective study involved a sample of 976 children from Kuwait based on mothers’ reporting. Data collection about the vaccination status of children and various health outcomes relevant to chronic and acute illnesses was performed based on structured questionnaires through an online survey. However, participants were classified into unvaccinated (n = 40), partially vaccinated (n = 222), and fully vaccinated (n = 714). Statistical analyses, including the chi-square test, Odds Ratios (OR), 95% Confidence Interval (CI), and logistic regression, were performed using SAS (Version 9.4) to determine the associations between vaccination status and health outcomes among children. Results: The study disclosed that vaccinated children showed an increased diagnosis of chronic (allergic rhinitis, allergies, autism spectrum, eczema, neuro-developmental disorders, learning disability, ADHD, and any chronic condition) and acute (whooping cough, pneumonia, rubella, hepatitis A or B, measles, mumps, meningitis, influenza, rotavirus, cancer, chronic fatigue, Crohn’s disease, inflammatory bowel disease, conduct disorder, diabetes type 1 or 2, rheumatoid arthritis, obesity, seizures, hearing loss, polio, diphtheria, tetanus, and depression) illnesses than unvaccinated children. The fully vaccinated children showed an increased prevalence of influenza diagnosis, while partially vaccinated children were more likely to be diagnosed with rheumatoid arthritis than unvaccinated children. In contrast, unvaccinated were more likely to have been diagnosed with chickenpox and encephalopathy than fully and partially vaccinated. Males with chronic and acute conditions had a lower incidence of allergies and pneumonia, respectively, whereas females had a reduced prevalence of acute illnesses, such as whooping cough, inflammatory bowel disease, and hepatitis A or B among vaccinated (n = 936;combination of partially vaccinated and fully vaccinated) children. Regarding medication use and health service applications, vaccinated children were more likely to use medications for fever, antibiotics, and allergies. In addition, they showed an increased rate of sick visits and emergency visits in the past twelve months. On the other hand, factors like age (2 - 5 years, 6 - 9 years, and 10 - 13 years), birth type (cesarian), and mother suffering during pregnancy (gestational diabetes) were significantly associated with NDD (learning disability, autism spectrum, and attention deficient hyperactivity disorder) in the adjusted analysis. In the interaction model of age and birth type, age (6 - 9 years;OR 5.3, 95% CI: 1.1, 25.3) and mother suffering (gestational diabetes;OR 2.5, 95% CI: 1.2, 5.2) during pregnancy were associated with NDD. Conclusion: The findings of this study showed that there are some cases where the infection rate is higher among the vaccinated compared to unvaccinated children, or there are no significant differences between the two groups in Kuwait. Upon controlling the factors in the interaction model, the age of 6 to 9 years and gestational diabetic mothers during pregnancy were associated with the synergistic increment of odds with NDD. These data findings are recommended to verify a larger and diverse group of samples to optimize the vaccination on health outcomes in Kuwait children. 展开更多
关键词 VACCINATION Partial Vaccination Neurodevelopmental Disorders Long-term Health Impacts AUTISM Chronic Conditions Acute Conditions KUWAIT
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Off-Pump Coronary Artery Bypass Grafting in Patients with Left Ventricular Dysfunction: Short-Term Results from a Single Center in Bangladesh
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作者 Muhit Abdullah Md. Abir Tazim Chowdhury +9 位作者 Satyajit Sharma Rehana Akther Munama Magdum Munjerin Refat Synthee Md. Zafar-Al-Nimari Saikat Das Gupta Saleh Ahmed Samir Kumar Biswas M. Quamrul Islam Talukder Farooque Ahmed 《World Journal of Cardiovascular Surgery》 2024年第9期145-156,共12页
Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-... Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-term outcomes and functional improvements in LVD patients post-OPCAB. Methods: The study included 200 coronary artery disease patients who underwent isolated off-pump coronary artery bypass grafting (OPCAB) at the National Heart Foundation Hospital and Research Institute between January 2019 and June 2020. Patients were categorized into Group 1, with a left ventricular ejection fraction (LVEF) of 30% - 39%, and Group 2, with an LVEF of 40% or higher. Echocardiographic assessments of left ventricular dimensions and ejection fraction were performed preoperatively, at discharge, and one month postoperatively. Results: In Group 1, preoperative left ventricular internal dimensions during diastole (LVIDd) and systole (LVIDs) were 53.48 ± 4.40 mm and 44.23 ± 3.93 mm, respectively, with a left ventricular ejection fraction (LVEF) of 35.28% ± 2.26%. At discharge, these values improved to 51.58 ± 4.04 mm (LVIDd), 41.23 ± 5.30 mm (LVIDs), and 39.25% ± 3.75% (LVEF). One month postoperatively, further improvements were observed: 46.29 ± 3.76 mm (LVIDd), 37.45 ± 3.68 mm (LVIDs), and 43.22% ± 4.67% (LVEF). Group 2 showed similar positive outcomes, with preoperative values of 47.09 ± 5.06 mm (LVIDd), 35.11 ± 5.25 mm (LVIDs), and 50.13% ± 7.25% (LVEF), improving to 42.37 ± 4.18 mm (LVIDd), 31.05 ± 4.19 mm (LVIDs), and 55.33% ± 7.05% (LVEF) at one month postoperatively. Both groups demonstrated significant improvements in left ventricular function and NYHA class, with most patients moving from class III/IV to I/II. Complications were minimal, and no mortality was observed. Conclusion: OPCAB is safe and effective for patients with LVEF 30% - 39% and LVEF ≥ 40%, providing significant short-term functional improvements without increased risk. 展开更多
关键词 Off-Pump Coronary Artery Bypass Grafting Left Ventricular Dysfunction (LVD) Short-term Outcomes
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A Trajectory Privacy Protection Method to Resist Long-Term Observation Attacks
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作者 Qixin Zhan 《Journal of Computer and Communications》 2024年第5期53-70,共18页
Users face the threat of trajectory privacy leakage when using location-based service applications, especially when their behavior is collected and stored for a long period of time. This accumulated information is exp... Users face the threat of trajectory privacy leakage when using location-based service applications, especially when their behavior is collected and stored for a long period of time. This accumulated information is exploited by opponents, greatly increasing the risk of trajectory privacy leakage. This attack method is called a long-term observation attack. On the premise of ensuring lower time overhead and higher cache contribution rate, the existing methods cannot utilize cache to answer subsequent queries while also resisting long-term observation attacks. So this article proposes a trajectory privacy protection method to resist long-term observation attacks. This method combines caching technology and improves the existing differential privacy mechanism, while incorporating randomization factors that are difficult for attackers to recognize after long-term observation to enhance privacy. Search for locations in the cache of both the mobile client and edge server that can replace the user’s actual location. If there are replacement users in the cache, the query results can be obtained more quickly. Simultaneously obfuscating the spatiotemporal correlation of actual trajectories by generating confusion regions. If it does not exist, the obfuscated location generation method that resists long-term observation attacks is executed to generate the real anonymous area and send it to the service provider. The above steps can comprehensively protect the user’s trajectory privacy. The experimental results show that this method can protect user trajectories from long-term observation attacks while ensuring low time overhead and a high cache contribution rate. 展开更多
关键词 Location Privacy Long-term Observation Attacks K-ANONYMITY Location Caching
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Photoelectric State with Long-Term Relaxation in CdTe:(Ag, Cu, Cd) and Sb2Se3:Se Photovoltaic Films
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作者 Ozodbek Ravshanboy o‘g‘li Nurmatov Dilkhumor Tolibjonovna Mamadieva Nosirjon Khaydarovich Yuldashev 《Journal of Applied Mathematics and Physics》 2024年第1期43-51,共9页
The results of an experimental study of long-term relaxation of the photoelectret state of polycrystalline CdTe:(Ag, Cu, Cd) and Sb<sub>2</sub>Se<sub>3</sub>:Se films with an anomalous photovol... The results of an experimental study of long-term relaxation of the photoelectret state of polycrystalline CdTe:(Ag, Cu, Cd) and Sb<sub>2</sub>Se<sub>3</sub>:Se films with an anomalous photovoltaic property are presented. In such films, the residual photovoltage is caused by the separation of photocarriers by the built-in electrostatic field of the near-surface region of space charges and their asymmetric capture by deep levels of impurities or complexes, including impurity atoms and intrinsic defects, both in the bulk and on the surface of crystal grains. It has been shown that in activated films, a two-step exponential temporary relaxation of the initial photovoltage of the order of V<sub>APV</sub> ≈ (500-600) V is detected, and only 10% of it experiences long-term relaxation (t ≈ 100-120 min). 展开更多
关键词 Thin Polycrystalline Films Doping Deep Centers Anomalous Photovoltage Photoelectret State Long-term Relaxation
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脂蛋白脂酶Ser447Term多态性和卒中相关危险因素相互作用对缺血性脑卒中发病的影响 被引量:1
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作者 杨玉梅 朱丹 吴江 《中风与神经疾病杂志》 CAS CSCD 北大核心 2013年第6期489-492,共4页
目的本研究旨在探讨脂蛋白脂酶(LPL)Ser447Term多态性与一些常见的卒中危险因素之间的相互影响。方法检测704个汉族缺血性脑卒中患者的基因型,根据这些患者所具有的卒中相关危险因素将其分为2型糖尿病组、高血压组、吸烟组和高脂血症组... 目的本研究旨在探讨脂蛋白脂酶(LPL)Ser447Term多态性与一些常见的卒中危险因素之间的相互影响。方法检测704个汉族缺血性脑卒中患者的基因型,根据这些患者所具有的卒中相关危险因素将其分为2型糖尿病组、高血压组、吸烟组和高脂血症组。应用聚合酶链反应-限制性片段长度多态性方法对Ser447Term的多态性进行基因分型。结果卡方(χ2)检验结果显示:在有糖尿病史的卒中患者中Ser447Term G等位基因的携带率显著高于无糖尿病史的卒中患者(χ2=7.25,P=0.007,OR=1.78,95%CI1.18~2.68)。这样的相关性并未在具有其他3个卒中相关的危险因素的患者中观察到。结论 LPL基因多态性与糖尿病的联合作用可能促成缺血性卒中的一个亚组的发病。 展开更多
关键词 缺血性卒中 糖尿病 脂蛋白脂酶 Ser447term多态性 单核苷酸多态性(SNP)
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长期施肥下土壤氮素指标与小麦/玉米产量关系研究
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作者 丁世杰 黄绍敏 +5 位作者 张水清 郭斗斗 宋晓 张珂珂 岳克 郭腾飞 《核农学报》 CAS 北大核心 2025年第1期157-169,共13页
为明确施肥对典型潮土区土壤氮素指标的影响以及氮素指标与作物产量的量化关系,本研究利用长期定位施肥试验系统评估施肥对土壤全氮、碱解氮、酸解有机氮组分、微生物量氮含量的影响,并进一步定量分析氮素指标与小麦、玉米产量间的关系... 为明确施肥对典型潮土区土壤氮素指标的影响以及氮素指标与作物产量的量化关系,本研究利用长期定位施肥试验系统评估施肥对土壤全氮、碱解氮、酸解有机氮组分、微生物量氮含量的影响,并进一步定量分析氮素指标与小麦、玉米产量间的关系。结果表明,与单施化肥或不施肥相比,长期化肥与秸秆或有机肥配施在显著提高土壤全氮含量的同时,对碱解氮、酸解总氮、酸解铵态氮、氨基酸态氮与微生物量氮含量的提高也有明显的促进作用。除土壤全氮外的其他氮素指标含量在高量化肥-有机肥配施、化肥-秸秆还田和常量化肥-有机肥配施处理间无显著差异。土壤全氮、微生物量氮和碱解氮含量是对作物产量影响程度相对较大的氮素指标。土壤全氮含量每增加0.1 g·kg^(−1),小麦和玉米分别增产822.7和968.2 kg·hm^(-2)。土微生物量氮与碱解氮含量每增加1 mg·kg^(−1),小麦增产195.2与58.1 kg·hm^(-2);玉米增产189.9与79.1 kg·hm^(-2)。酸解总氮与氨基酸态氮含量对小麦产量也有显著影响,酸解总氮与氨基酸态氮含量每增加1 mg·kg^(−1),小麦分别增产15.8与30.0 kg·hm^(-2)。综上所述,化肥与秸秆或有机肥配施可提高潮土氮素库容与供氮能力。小麦、玉米产量随土壤全氮、微生物量氮与碱解氮含量的提高呈线性增长,小麦产量与酸解总氮和氨基酸态氮含量呈显著正相关。本研究为典型潮土区地力培育与粮食丰产提供了理论依据和技术支撑。 展开更多
关键词 长期定位试验 施肥 土壤氮素指标 作物产量
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基于分类的term重要性识别方法
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作者 邱云飞 鲍莉 邵良杉 《计算机科学》 CSCD 北大核心 2013年第11期242-247,共6页
在传统的搜索引擎和信息检索中,用户Query中的term-weight通常是以一种上下文无关的方式得到的。现有的大多数信息检索技术都使用词袋方法,例如布尔模型、向量空间模型和概率模型等,这些方法均没有考虑Query中term之间的相关性。为了能... 在传统的搜索引擎和信息检索中,用户Query中的term-weight通常是以一种上下文无关的方式得到的。现有的大多数信息检索技术都使用词袋方法,例如布尔模型、向量空间模型和概率模型等,这些方法均没有考虑Query中term之间的相关性。为了能够充分利用Query中的信息来提高term-weight的准确度,提出了一种有监督的机器学习方法来学习用户Query中的term-weight。该方法基于分类的方法,并引入了句法分析作为分类的一项重要的特征来训练模型。考虑用户Query中term之间的关系后,既避免了由Query到单个term的信息丢失,又增加了短文本的特征,同时使分类器实现软输出,能够给term的重要程度一个更为准确的量化值。 展开更多
关键词 分类 依存句法分析 查询词权重 查询分析 term重要性 搜索引擎 信息检索
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“Long-term care”概念辨析 被引量:26
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作者 娄方丽 尚少梅 《护士进修杂志》 2012年第22期2035-2037,共3页
Long-term care(LTC)在国外最早是以救济贫穷个人或家庭为目标。随着人口结构、家庭结构以及社会结构的变化,要求医疗护理模式作出相应的调整,也使LTC的存在有了更充分的理由,因此LTC是社会发展到一定时期的必然产物。迄今为止,我国... Long-term care(LTC)在国外最早是以救济贫穷个人或家庭为目标。随着人口结构、家庭结构以及社会结构的变化,要求医疗护理模式作出相应的调整,也使LTC的存在有了更充分的理由,因此LTC是社会发展到一定时期的必然产物。迄今为止,我国学术界对"long-term care"的中文翻译问题依然没有统一的看法。因此,很有必要就此展开深入研究和讨论。笔者将全面辨析和讨论“long-termcare”概念,并在此基础上探讨“long-termcare”的中文翻译问题,从而进一步廓清“long-termcare”的涵义。 展开更多
关键词 长期护理 概念辨析
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On the conceptual metaphor of color terms: A typological view 被引量:1
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作者 宋宏 《Sino-US English Teaching》 2009年第1期23-25,共3页
In different languages and cultures, color terms usually indicate their specific cultural concepts and metaphorical implicature. This paper makes a typological study on the universality and relativity of the Conceptua... In different languages and cultures, color terms usually indicate their specific cultural concepts and metaphorical implicature. This paper makes a typological study on the universality and relativity of the Conceptual Metaphors (CM) of color terms in different languages. It attempts to explore the cognitive differences and similarities in the process of categorization and metaphorization of color terms of oriental and western peoples. It proposes that the CM system of color terms is determined by the interactivity of three factors as neurophysiologic mechanisms, general cognitive psychological mechanisms and socio-cultural selective mechanisms. The CM of color terms in different languages carry their specific cognitive characteristics and cultural values, and reflect self-similarity of the language and culture. 展开更多
关键词 color terms conceptual metaphor COGNITION language typology
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日本FI/F-term分类体系在专利技术/功效矩阵中的应用研究 被引量:18
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作者 霍翠婷 蒋勇青 +1 位作者 凌锋 刘会景 《情报杂志》 CSSCI 北大核心 2013年第11期140-144,共5页
随着创新型企业对专利信息服务品质和服务深度提出越来越高的要求,基于数理统计的基本专利分析方法已经不能满足实际应用需求,针对技术层面深度剖析的专利技术/功效矩阵分析成为能够为企业技术创新提供有力支撑的重要有效手段。本研究... 随着创新型企业对专利信息服务品质和服务深度提出越来越高的要求,基于数理统计的基本专利分析方法已经不能满足实际应用需求,针对技术层面深度剖析的专利技术/功效矩阵分析成为能够为企业技术创新提供有力支撑的重要有效手段。本研究根据专利技术/功效矩阵的制作流程,探索性利用日本专利检索体系中的FI/Fterm分类体系进行数据分类标引预处理,并基于实例进行实际应用可行性验证,从而形成面向特定技术主题的专利技术/矩阵分析方法。最后,简单阐述该方法的相关注意事项以及应用前景。 展开更多
关键词 专利FI F-term分类体系 主题分类应用流程技术 功效矩阵 多点触控
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