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Complete f-Moment Convergence for Sung’s Type Weighted Sums of Negatively Superadditive Dependent Random Variables
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作者 HU Xueping WANG Liuliu +1 位作者 HU Ke XU Zhonghao 《应用概率统计》 北大核心 2025年第4期585-601,共17页
In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergen... In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergence of NSD random variables.We establish and improve a general result on the complete f-moment convergence for Sung’s type randomly weighted sums of NSD random variables under some general assumptions.As an application,we show the complete consistency for the randomly weighted estimator in a nonparametric regression model based on NSD errors. 展开更多
关键词 Marcinkiewicz-Zygmund inequality Rosenthal-type inequality Sung’s type randomly weighted sums negatively superadditive dependent random variables complete f-moment convergence
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Complete q-Order Moment Convergence of Moving Average Processes Generated by Negatively Dependent Random Variables under Sub-Linear Expectations
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作者 Mingzhou XU 《Journal of Mathematical Research with Applications》 2025年第3期395-410,共16页
Assume that{a_(i),−∞<i<∞}is an absolutely summable sequence of real numbers.We establish the complete q-order moment convergence for the partial sums of moving average processes{X_(n)=Σ_(i=−∞)^(∞)a_(i)Y_(i+... Assume that{a_(i),−∞<i<∞}is an absolutely summable sequence of real numbers.We establish the complete q-order moment convergence for the partial sums of moving average processes{X_(n)=Σ_(i=−∞)^(∞)a_(i)Y_(i+n),n≥1}under some proper conditions,where{Yi,-∞<i<∞}is a doubly infinite sequence of negatively dependent random variables under sub-linear expectations.These results extend and complement the relevant results in probability space. 展开更多
关键词 moving average processes negatively dependent random variables complete moment convergence sub-linear expectations
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Precise Control of the Recollision Dynamics in Nonsequential Double Ionization by Spatially Inhomogeneous Few-Cycle Negatively Chirped Laser Pulses
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作者 Yingbin Li Fengrun Wu +10 位作者 Fanfei Liu Shuaijie Kang Zhengfa Li Ke Zhang Yifan Liu Kuo Li Chunyang Zhai Jingkun Xu Pu Wang Qiming Zhao Benhai Yu 《Chinese Physics Letters》 2025年第5期26-32,共7页
With a three-dimensional semiclassical ensemble method, we theoretically investigated the nonsequential double ionization of Ar driven by the spatially inhomogeneous few-cycle negatively chirped laser pulses. Our resu... With a three-dimensional semiclassical ensemble method, we theoretically investigated the nonsequential double ionization of Ar driven by the spatially inhomogeneous few-cycle negatively chirped laser pulses. Our results show that the recollision time window can be precisely controlled within an isolated time interval of several hundred attoseconds, which is useful for understanding the subcycle correlated electron dynamics. More interestingly, the correlated electron momentum distribution (CEMD) exhibits a strong dependence on laser intensity. That is, at lower laser intensity, CEMD is located in the first quadrant. As the laser intensity increases,CEMD shifts almost completely to the second and fourth quadrants, and then gradually to the third quadrant.The underlying physics governing the CEMD's dependence on laser intensity is explained. 展开更多
关键词 recollision time window recollision dynamics correlated electron momentum distribution nonsequential double ionization precise control understanding subcycle correlated electron dynamics three dimensional semiclassical ensemble method spatially inhomogeneous few cycle negatively chirped laser pulses
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Clinical Effect Analysis of Negative Pressure Chest Drainage in Patients after Two-Port Thoracoscopic Valve Surgery
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作者 Yanfang Wei Aizhen Wei +3 位作者 Yuan Feng Jinmao Lu Shusong Li Linqiang Li 《Natural Science》 2025年第2期7-12,共6页
Objective: This study aims to investigate the drainage effect and clinical outcomes of negative pressure chest drainage in patients after two-port thoracoscopic valve surgery, comparing the differences in postoperativ... Objective: This study aims to investigate the drainage effect and clinical outcomes of negative pressure chest drainage in patients after two-port thoracoscopic valve surgery, comparing the differences in postoperative pain, hospital stay, and other factors between the negative pressure group and the control group. Methods: This study is a prospective controlled trial that selected patients undergoing two-port thoracoscopic valve surgery at a certain hospital from January 2019 to December 2024. Patients were randomly assigned to the control group and the negative pressure group using a random number table method. The control group consisted of 30 patients (20 males, 10 females, mean age 42.03 ± 12.89 years), and the negative pressure group consisted of 35 patients (26 males, 9 females, mean age 41.84 ± 11.83 years). The control group received traditional chest drainage, while the negative pressure group received negative pressure chest drainage. Postoperative pain scores, hospital stay, drainage time, number of tube blockages, and incidences of pneumothorax or subcutaneous emphysema were recorded and statistically analyzed. Results: The negative pressure group had a significantly shorter postoperative drainage time compared to the control group (49.09 ± 11.99 hours vs. 79.10 ± 7.32 hours, P < 0.001). The postoperative pain score was lower in the negative pressure group (4.49 ± 1.27 vs. 7.03 ± 0.85, P < 0.001), and the hospital stay was significantly shorter (9.83 ± 1.69 days vs. 14.73 ± 2.32 days, P < 0.001). The incidence of pneumothorax or subcutaneous emphysema was significantly lower in the negative pressure group than in the control group (14.29% vs. 56.67%, P = 0.0003). Conclusion: The application of negative pressure chest drainage in patients after two-port thoracoscopic valve surgery can effectively reduce postoperative pain, shorten hospital stay, and lower the incidence of tube blockage and pneumothorax, demonstrating good clinical outcomes. 展开更多
关键词 negative Pressure Chest Drainage Two-Port Thoracoscopy Valve Surgery Cardiac Surgery
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EAST装置中新型吸附剂泵(NEG)抽速标定研究
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作者 王超 余耀伟 +4 位作者 孙浩 曹斌 潘浩 凡斌 左桂忠 《真空与低温》 2024年第3期243-247,共5页
粒子排出是控制燃料粒子再循环、提升等离子体性能的关键因素之一。因此研究了新型吸附剂泵(NEG)在粒子排出技术中的潜在应用。NEG泵基于ZAO新型合金材料制成,对氢及其同位素抽速大、容量高,安装、运行、维护简单,兼容等离子体环境,适... 粒子排出是控制燃料粒子再循环、提升等离子体性能的关键因素之一。因此研究了新型吸附剂泵(NEG)在粒子排出技术中的潜在应用。NEG泵基于ZAO新型合金材料制成,对氢及其同位素抽速大、容量高,安装、运行、维护简单,兼容等离子体环境,适用于偏滤器区域的超高热流和复杂的空间结构。在EAST托卡马克装置安装4套HV800模组,开展了定期的抽速标定、再生研究以评估其周期性能变化。EAST真空室壁表面积较大,金属壁放气、杂质气体影响NEG泵抽速计算。通过计算EAST整体漏放率与氢及其同位素放气率,利用计算机模拟抽气过程,提出了一种用于修正NEG泵抽速的方法。研究结果表明在偏滤器区域工作压力下,对氘平均抽速可达1200 L/s。 展开更多
关键词 neg 真空抽气系统 抽气速率标定
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Relativistic Mechanics in Positive and Negative Subspace-Time according to the Inverse Relativity Model
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作者 Michael Girgis 《Journal of Applied Mathematics and Physics》 2024年第11期3784-3815,共32页
In the second paper on the inverse relativity model, we explained in the first paper [1] that analyzing the four-dimensional displacement vector on space-time according to a certain approach leads to the splitting of ... In the second paper on the inverse relativity model, we explained in the first paper [1] that analyzing the four-dimensional displacement vector on space-time according to a certain approach leads to the splitting of space-time into positive and negative subspace-time. Here, in the second paper, we continue to analyze each of the four-dimensional vectors of velocity, acceleration, momentum, and forces on the total space-time fabric. According to the approach followed in the first paper. As a result, in the special case, we obtain new transformations for each of the velocity, acceleration, momentum, energy, and forces specific to each subspace-time, which are subject to the positive and negative modified Lorentz transformations described in the first paper. According to these transformations, momentum remains a conserved quantity in the positive subspace and increases in the negative subspace, while the relativistic total energy decreases in the positive subspace and increases in the negative subspace. In the general case, we also have new types of energy-momentum tensor, one for positive subspace-time and the other for negative subspace-time, where the energy density decreases in positive subspace-time and increases in negative subspace-time, and we also obtain new gravitational field equations for each subspace-time. 展开更多
关键词 4D Velocity Vector Analysis Positive Subspace negative Subspace negative Relativistic Mechanics Positive Tensor of Energy and Momentum Inverse Theory of Relativity
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差压法测定NEG吸氢性能
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作者 王婧华 王蓝陵 +3 位作者 林文豫 吴俊 曹青 王旭迪 《真空》 CAS 2024年第3期51-56,共6页
通过对定压法进行改进提出了差压法,用于测试非蒸散型吸气剂(NEG)的吸氢性能。该方法在进气室和吸气室之间安装固定流导元件,利用调节微调阀提供可控的进气流量,通过测量吸气室、进气室和参考室的压力计算NEG的吸气性能参数。利用两种NE... 通过对定压法进行改进提出了差压法,用于测试非蒸散型吸气剂(NEG)的吸氢性能。该方法在进气室和吸气室之间安装固定流导元件,利用调节微调阀提供可控的进气流量,通过测量吸气室、进气室和参考室的压力计算NEG的吸气性能参数。利用两种NEG比较了差压法和改进的定压法所测吸气性能。结果表明:差压法测得的吸气容量比改进的定压法测得的吸气容量低0.07268 Pa·L;腔室壁面吸附能力使改进定压法的试验结果高于理论结果,而差压法的试验结果不受影响;对改进的定压法进行优化后,其计算结果与差压法的接近。差压法可以获得更准确、更有效的吸气剂性能参数,在差压法中,参考部分和试验部分同时进行测试,可缩短测试时间,减少控制进气带来的误差。 展开更多
关键词 差压法 吸氢性能 非蒸散型吸气剂(neg) 改进的定压法
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The Prevalence of Overweight/Obesity and Related Comorbidities among HIV-Positive and HIV-Negative Patients Attending the Same Clinics in Gaborone, Botswana
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作者 Jose Gaby Tshikuka Matshwenyego Boitshwarelo +3 位作者 Shimeles Genna Hamda Roy Tapera Ngoyi Kashiba Zacharie Bukonda Marie Esako Onokoko 《Advances in Infectious Diseases》 CAS 2024年第3期523-540,共18页
Context: Antiretroviral therapy (ART) helps restore the health status of people living with HIV (PLHIV). Likewise, it increases the risk of overweight/obesity and related comorbidities among the recipients. In countri... Context: Antiretroviral therapy (ART) helps restore the health status of people living with HIV (PLHIV). Likewise, it increases the risk of overweight/obesity and related comorbidities among the recipients. In countries like Botswana where ±84% of PLHIV is on ART, the paucity of data comparing overweight/obesity between HIV-positive on ART and HIV-negative patients may impede clinical and policy decision-making. This study sought to estimate and compare: i) the prevalence of overweight/obesity between HIV-positive on ART and HIV-negative patients;ii) the prevalence of hypertension (HTN), diabetes mellitus (DM)/coronary heart disease (CHD) between HIV-positive patients on ART and HIV-negative patients attending same outpatient departments of general clinics in Gaborone, Botswana. Patients and Methods: Five hundred eighty-one (581) outpatients were recruited in four major clinics of Gaborone, Botswana, between June and July 2019;294 or 51% of them were HIV-negative and 287 or 49% were HIV-positive on ART. The prevalence of overweight/obesity and of HTN and DM/CHD were calculated and examined using stratified analysis. Subgroups were compared using Chi-square analysis with Yates correction or Fisher exact test and t-student test for continuous data. Results: Major findings after stratification of the study population by HIV status were: i) the prevalence of all categories of (BMI), including overweight/obesity, were comparable between HIV-negative-patients and HIV-positive. In fact, there were 24 (8.0%) cases of underweight among HIV-negative-Patients and 15(5%) cases among HIV-positive patients, p = 0.2;145 (49%) HIV-negative-patients and 128 (45%) HIV-positive, p = 0.07 cases of normal weight;72 (25%) HIV-negative-patients and 87 (30%) HIV-positive, p = 0.08, were overweight;53 (18%) HIV-negative-patients and 57 (20%) HIV-positive, p = 0.12, were obese;125 (43%) HIV-negative patients and 144 (50%) HIV-positive, p=0.06 were overweight/obese;ii) the prevalence of HTN and DM/CHD among HIV-positive-patients were significantly lower (p < 0.05) compared to HIV-negative patients: There were 32 (10.9%) cases of HTN among HIV-negative patients compared to 18 (6.3%) cases of HTN among HIV-positive patients, p = 0.001;32 (11%) cases of DM/CHD HIV-negative patients compared to 4 (1.4%) cases of DM/CHD among HIV-positive patients, p = 0.001. Conclusion: the prevalence of overweight/obesity observed between HIV-negative and HIV-positive patients may suggest that the two groups shared the same exposure factors. That HTN and DM/CHD prevalence was lower among HIV-positive compared to HIV-negative patients, is possibly due to interplay factors of ART, HIV or the host population. Further studies are, however, recommended for clarifications. 展开更多
关键词 OVERWEIGHT/OBESITY Related Comorbidities HIV-POSITIVE HIV-negative
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Molecular Detection of Resistance and Virulence Genes in Coagulase Negative Staphylococci Isolated from Blood Cultures at the University Teaching Hospital of Bouake
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作者 Oby Zéphirin Wayoro Ahou Micheline N’Guessan +7 位作者 Adjaratou Traore Akissi Christine Houssou Etilé Augustin Anoh Abdoulaye Diarrassouba Safiatou Karidioula Juste Olivier Tadet Pacôme Monemo Chantal Akoua-Koffi 《Journal of Biosciences and Medicines》 2024年第6期52-63,共12页
Introduction: Coagulase-negative staphylococci (CoNS) are currently recognized as genuine pathogens. However, little is known about the resistance and virulence genes that explain their pathogenicity in hospitals in C... Introduction: Coagulase-negative staphylococci (CoNS) are currently recognized as genuine pathogens. However, little is known about the resistance and virulence genes that explain their pathogenicity in hospitals in Cte d'Ivoire. The aim of this study was to contribute to the genotypic identification of resistance and virulence genes in CoNS isolated from blood cultures at the University Teaching Hospital (CHU) of Bouak, in order to improve patient management. Material and Methods: This was a descriptive study conducted from September to December 2023. The CoNS isolates studied came from the collection of strains isolated from blood cultures of febrile patients hospitalized or attending consultations at the CHU of Bouak. The strains were analyzed using conventional simplex PCR. Results: Of the 45 isolates analyzed, 46.7% carried both the aacA-aphD and tetK genes and 40% carried the mecA gene. With regard to virulence genes, only the LukS-PV gene was observed in S. epidermidis and S. haemolyticus isolates. Conclusion: The high prevalence of CoNS isolates carrying the mecA gene and the presence of virulence genes observed in this study give cause for concern in hospitals. It is important to develop comprehensive surveillance strategies against nosocomial and multi-resistant infections at the CHU of Bouak. 展开更多
关键词 Coagulase-negative Staphylococcus GENE MULTIRESISTANCE VIRULENCE Bouaké
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Low-Level Antibiotic Resistance among Staphylococcus aureus and Gram-Negative Pathogens from Infected Skin and Soft Tissues in Rural Kenya
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作者 Justin Nyasinga Zubair Munshi +3 位作者 Lillian Musila Ephantus Mbugua Geoffrey Omuse Gunturu Revathi 《Open Journal of Medical Microbiology》 2024年第1期23-38,共16页
Introduction: Bacterial skin and soft tissue infections (SSTIs) are a cause of frequent inpatient and outpatient care visits whose causative agents are associated with a high antimicrobial resistance burden. For insig... Introduction: Bacterial skin and soft tissue infections (SSTIs) are a cause of frequent inpatient and outpatient care visits whose causative agents are associated with a high antimicrobial resistance burden. For insights on antimicrobial susceptibilities in a rural setting, we examined specimens from suspected SSTIs from two public health facilities in Kenya. We additionally assessed antibiotic use, appropriateness of empiric therapy and risk factors for SSTI. Methodology: Between 2021 and 2023, 265 patients at Kisii and Nyamira County Referral hospitals were enrolled. Wound swabs/aspirates were collected and processed following standard microbiological procedures. Identification and antimicrobial susceptibility were performed using the VITEK 2 Compact platform. Demographic, clinical, and microbiological data were analyzed with R Statistical software. Results: S. aureus was isolated in 16.2% (43/265) of patients with a methicillin resistance (MRSA) proportion of 14% (6/43). While 13/15 drugs elicited susceptibilities ranging from 84% - 100%, penicillin (16%) and trimethoprim-sulfamethoxazole [TMP-SXT] (23%) yielded the lowest susceptibilities. Escherichia coli (n = 33), Klebsiella pneumoniae (n = 8), Pseudomonas aeruginosa (n = 8), and Citrobacter species (n = 4) were the most commonly isolated gram-negative species. Gram-negative strains showed high susceptibilities to most of the tested drugs (71% - 100%) with the exception of ampicillin (18%), TMP-SXT (33%), and first and second generation cephalosporins. Conclusions: The low MRSA prevalence and generally high antibiotic susceptibilities for S. aureus and gram-negative bacteria present opportunities for antibiotic stewardship in the study setting. Diminished susceptibilities against penicillin/ampicillin and TMP-SXT accord with prevailing local data and add a layer of evidence for their cautious empiric use. 展开更多
关键词 S. aureus MRSA Gram-negative Bacteria Antimicrobial Resistance SSTIs Kenya
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Comparison Study of Different Drainage Tube Diameters with Negative Pressure Suction after Valve Replacement Surgery
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作者 Yanfang Wei Yuan Feng +1 位作者 Shusong Li Linqiang Li 《Open Journal of Nursing》 2024年第11期591-597,共7页
Objective: This study aims to compare the effects of different drainage tube diameters (22F vs. 26F) combined with negative pressure suction on patients after valve replacement surgery, including postoperative indicat... Objective: This study aims to compare the effects of different drainage tube diameters (22F vs. 26F) combined with negative pressure suction on patients after valve replacement surgery, including postoperative indicators and complications. Methods: A total of 104 patients undergoing valve replacement surgery were included and divided into a 22F group (45 patients) and a 26F group (59 patients). The basic characteristics, postoperative ICU stay duration, drainage duration, postoperative complications, and pain scores were compared between the two groups. All data were analyzed using SPSS statistical software, with p Results: There were no significant differences between the two groups in terms of age, sex, and underlying diseases. The ICU stay duration and drainage duration showed no significant differences (p > 0.05). The total drainage volume in the 22F group was significantly lower than that in the 26F group (225 vs. 380 ml, p = 0.035), and the pain scores on the third postoperative day were also significantly lower in the 22F group (p Conclusion: Compared to the 26F group, patients in the 22F group exhibited less postoperative drainage volume and lower pain scores, suggesting that the 22F drainage tube may have better clinical outcomes after valve replacement surgery. 展开更多
关键词 Valve Replacement Surgery Drainage Tube negative Pressure Suction Postoperative Complications Pain Score
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Prevalence of Pneumocystis jirovecii in Smear Negative Sputum Samples at the Coast General Teaching and Refferral Hospital in Kenya
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作者 Anne Saitoti Fred Wamunyokoli +2 位作者 Sally Loroyokie Njerwanna Charles Syego Christine Bii 《Journal of Tuberculosis Research》 2024年第4期215-231,共17页
Pneumcystis jirovecii is a pathogen that causes Pneumocystis pneumonia (PCP), an infection in (HIV/ADS) and other immunocompromised patients. The rare reports of P. jirovecii pneumonia in sub-Saharan Africa are contro... Pneumcystis jirovecii is a pathogen that causes Pneumocystis pneumonia (PCP), an infection in (HIV/ADS) and other immunocompromised patients. The rare reports of P. jirovecii pneumonia in sub-Saharan Africa are controversial due to the high HIV/AIDS seropositivity. The study determined the significance of P. jirovecii in TB smear negative retreatment patients at the Coast General Teaching Referral Hospital-Mombasa. Sputum samples were subjected to toluidine blue O(TBO) stain for microscopy and polymerase chain reaction (PCR). A total of 100 TB smear negative participants were enrolled in the study and expectorated sputum was collected. Out of the 100 patients, 63 men and 37 women. Patients aged 31 to 53 made up 62% of the patients. The patients aged 31 to 53 made up 75% of the patients (Min = 11y, Max = 85y). The median age of the patients was 42 years. Nested PCR has a prevalence of 41% (41 instances). TBO staining has a prevalence of 29% (29 instances). Detecting an additional 13 more patients than toluidine O staining technique. The sensitivity of toluidine blue O staining was 33.82%, which indicates that it correctly identified 33.82% of true positive cases compared to PCR. The specificity of toluidine blue O staining was 97.82%, indicating that it had a high ability to correctly identify true negative cases compared to PCR, suggesting that it was good at ruling out non-P. jirovecii cases. The study confirms that P. jirovecii is as a significant cause of persistent symptoms in TB patients that could be responsible for persistent symptoms despite TB treatment. We recommend fungal diagnostics in such patients before retreatment. 展开更多
关键词 Pneumocystis jirovecii Nested PCR Pulmonary tuberculosis Smear negative
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The ConMan Trial: Coagulase Negative Staphylococcal Infections: To Treat or Not to Treat
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作者 David Levine Henry Spratt +5 位作者 Caitlin Crews-Stowe Ryan Mart Jarle Stone Lani Gao Michael Davis Lindsey Brunton 《Open Journal of Blood Diseases》 2024年第4期91-100,共10页
Background: Coagulase negative Staphylococci (CoNS) positive blood cultures represent a complex and common challenge in clinical medicine. CoNS are common in skin flora and are often mistaken as contamination. Convers... Background: Coagulase negative Staphylococci (CoNS) positive blood cultures represent a complex and common challenge in clinical medicine. CoNS are common in skin flora and are often mistaken as contamination. Conversely, CoNS can also be implicated in severe and life-threatening bacteremia requiring prompt treatment. A gray area in terms of treatment approach exists for health care providers. The primary aim of this study was to examine predictive factors in patients who have positive CoNS blood cultures that met the CDC case definition of a laboratory confirmed bloodstream infection (LCBI-II) that were subsequently found to have clinically significant true bacteremia. Methods: A retrospective cohort of 288 patients that had at least two separate blood cultures positive for a coagulase negative Staphylococci between November 1st, 2017, and November 1st, 2018, were examined to determine if there were any patient specific factors that would indicate a true bacteremia with CoNS. Results: Retrospective regression analysis demonstrated that those subjected to antibiotics for two days or more (OR = 3.01), those subjected to antibiotics for seven days or more (OR = 2.86), and patients with central access (OR = 4.06) were more likely to have a true infection. Although not statistically significant, an association was also found in immunosuppressed patients (OR = 1.65), and in patients with implanted hardware (OR = 1.16). Conclusion: Patients receiving antibiotics for greater than two days and patients with a central line were more likely to have a true bloodstream infection with coagulase negative Staphylococci. 展开更多
关键词 Coagulase negative Staphylococci (CoNS) Positive Blood Culture True Bacterium Central Access IMMUNOSUPPRESSED Infectious Disease
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Assessing the Robustness of the Negative Binomial Multiple Change Point Algorithm Using Synthetic Data
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作者 Shalyne Nyambura Anthony Waititu +1 位作者 Antony Wanjoya Herbert Imboga 《Open Journal of Statistics》 2024年第6期775-789,共15页
The Negative Binomial Multiple Change Point Algorithm is a hybrid change detection and estimation approach that works well for overdispersed and equidispersed count data. This simulation study assesses the performance... The Negative Binomial Multiple Change Point Algorithm is a hybrid change detection and estimation approach that works well for overdispersed and equidispersed count data. This simulation study assesses the performance of the NBMCPA under varying sample sizes and locations of true change points. Various performance metrics are calculated based on the change point estimates and used to assess how well the model correctly identifies change points. Errors in estimation of change points are obtained as absolute deviations of known change points from the change points estimated under the algorithm. Algorithm robustness is evaluated through error analysis and visualization techniques including kernel density estimation and computation of metrics such as change point location accuracy, precision, sensitivity and false positive rate. The results show that the model consistently detects change points that are present and does not erroneously detect changes where there are none. Change point location accuracy and precision of the NBMCPA increases with sample size, with best results for medium and large samples. Further model accuracy and precision are highest for changes located in the middle of the dataset compared to changes located in the periphery. 展开更多
关键词 Kernel Density Estimation PRECISION Changepoint Location Accuracy Sensitivity negative Binomial Multiple Change Point Algorithm
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NEG镀膜真空盒在线激活的初步研究 被引量:2
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作者 马文静 赵壮 +5 位作者 张善才 王思慧 洪远志 范乐 王成宏 尉伟 《强激光与粒子束》 CAS CSCD 北大核心 2022年第8期113-118,共6页
合肥先进光源(HALF)是一台正在规划中的衍射极限同步辐射光源,其紧凑的物理设计和小孔径磁铁导致传统离散分布的真空泵系统很难达到衍射极限储存环所需的超高真空环境。镀有NEG(Non-Evaporable Getter)薄膜的小孔径真空盒不仅节约空间,... 合肥先进光源(HALF)是一台正在规划中的衍射极限同步辐射光源,其紧凑的物理设计和小孔径磁铁导致传统离散分布的真空泵系统很难达到衍射极限储存环所需的超高真空环境。镀有NEG(Non-Evaporable Getter)薄膜的小孔径真空盒不仅节约空间,还具有分布式吸气的能力,能满足衍射极限装置对超高真空的需求。NEG膜层需要在一定温度下激活才能具有吸气作用,因此在满足其他部件安全的前提下,它的激活方法与工艺十分重要。本文通过建立在线激活NEG薄膜的温度分析模型,模拟在加热温度为180℃和200℃情况下的NEG镀膜真空盒及磁铁的温度分布;采用聚酰亚胺加热膜缠绕管道的加热方式对管道的在线激活工艺进行初步研究,完成银铜(OFS)真空管在线激活时的温度测量,测得磁铁最高温度保持在40℃左右,验证了NEG镀膜真空管在线激活时四极磁铁的安全性。此研究为合肥先进光源NEG镀膜真空盒在线激活提供了解决方案和工作基础。 展开更多
关键词 衍射极限装置 超高真空 小孔径 neg镀膜真空盒 neg激活
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原因型“又+Neg+Xp”构式的会话功能 被引量:7
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作者 程亚恒 《汉语学习》 CSSCI 北大核心 2016年第4期27-33,共7页
"又+Neg+Xp"结构是现代汉语中常见的一种否定表达式,依据语境可以划分为不同的语义类型。其中,原因型构式"又+Neg+Xp"通常依据语义背景而存在,是针对语义背景中相关的Vp或Ap做出的分析性解释,具有阐述原因的作用,构... "又+Neg+Xp"结构是现代汉语中常见的一种否定表达式,依据语境可以划分为不同的语义类型。其中,原因型构式"又+Neg+Xp"通常依据语义背景而存在,是针对语义背景中相关的Vp或Ap做出的分析性解释,具有阐述原因的作用,构件"又"是一个引起语义推导的语篇衔接算子。原因型构式"又+Neg+Xp"表达一种"不应该"的情态意义,从会话功能来看,具有引起语义推导的话语提示功能。 展开更多
关键词 “又+neg+Xp”构式 语义背景 推导 语篇衔接
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吉西他滨联合顺铂一线治疗晚期triple-negative乳腺癌41例临床研究 被引量:3
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作者 葛伯建 顾寄树 谭清和 《现代肿瘤医学》 CAS 2011年第9期1780-1782,共3页
目的:观察吉西他滨联合顺铂(GP)一线治疗triple-negative(ER、PR、HER-2均阴性)晚期转移性乳腺癌的疾病进展时间、疗效和安全性。方法:2008年1月-2010年4月共41例经免疫组化检查证实为tri-ple-negative的晚期乳腺癌初治患者参与研究。... 目的:观察吉西他滨联合顺铂(GP)一线治疗triple-negative(ER、PR、HER-2均阴性)晚期转移性乳腺癌的疾病进展时间、疗效和安全性。方法:2008年1月-2010年4月共41例经免疫组化检查证实为tri-ple-negative的晚期乳腺癌初治患者参与研究。患者接受吉西他滨联合顺铂方案治疗:吉西他滨1000mg/m2,静脉滴注30min,d1、d8;顺铂25mg/m2静脉滴注d1-3天,21天重复。结果:全组41例共完成160个周期的治疗,中位数4个周期,范围2-6个周期,均可评价疗效。完全缓解(CR)2例(4.88%),部分缓解(PR)21例(51.22%),病情稳定(SD)7例(17.07%),病情进展(PD)11例(26.83%)。临床总缓解率(CR+PR)56.10%;疾病控制率(CR+PR+SD)73.17%;中位疾病进展时间(mTTP)8.4个月,1年生存率65.85%。不良反应主要为Ⅰ-Ⅱ度骨髓抑制、末梢神经毒性、胃肠道反应、轻度肝功能损伤等。结论:吉西他滨联合顺铂一线治疗triple-negative晚期转移性乳腺癌患者,初步观察疗效较好,不良反应可耐受,值得进一步研究。 展开更多
关键词 triple-negative乳腺癌 吉西他滨 顺铂 化疗
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光电负阻晶体管PNEGIT的电路模型和模拟 被引量:1
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作者 毛陆虹 郭维廉 +4 位作者 李树荣 郑云光 张世林 沙亚男 吴霞宛 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2000年第9期882-886,共5页
给出了光表面控制负阻晶体管 PNEGIT( Photo- Controlled Surface Negative ImpedanceTransistor)的电路模型 ,从栅控晶体管数学模型出发并结合光电池的电路模型 ,用电路模型描写带有表面复合和体复合的器件 ,模型为研究 PNEGIT和表面... 给出了光表面控制负阻晶体管 PNEGIT( Photo- Controlled Surface Negative ImpedanceTransistor)的电路模型 ,从栅控晶体管数学模型出发并结合光电池的电路模型 ,用电路模型描写带有表面复合和体复合的器件 ,模型为研究 PNEGIT和表面控制负阻晶体管 NEGIT( Surface- Controlled Negative Impedance Transistor)以及探讨该类器件的新用途提供了一种手段 。 展开更多
关键词 PnegIT 电路模型 模拟 光电负阻晶管
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Pan-negative型非小细胞肺癌的研究进展 被引量:2
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作者 孙丽 熊志成 韩琤波 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第2期129-138,共10页
近年来随着对肿瘤驱动基因的不断探索和分子检测技术的快速发展,在非小细胞肺癌(non-small cell lung cancer,NSCLC)领域,一系列的驱动基因如EGFR、KRAS、BRAF、PIK3CA、ALK和ROS-1等相继被发现,并逐渐研发出相应的针对特定驱动基因变... 近年来随着对肿瘤驱动基因的不断探索和分子检测技术的快速发展,在非小细胞肺癌(non-small cell lung cancer,NSCLC)领域,一系列的驱动基因如EGFR、KRAS、BRAF、PIK3CA、ALK和ROS-1等相继被发现,并逐渐研发出相应的针对特定驱动基因变异的靶向治疗药物,使NSCLC患者的生存得到极大改善。尽管如此,仍有部分NSCLC患者未能检测到任何已知驱动基因变异,称之为pan-negative型NSCLC。本文就pan-negative型NSCLC的概念、临床病理和流行病学特点以及治疗预后等作一综述。 展开更多
关键词 肺肿瘤 驱动基因 Pan-negative
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Cultural Regeneration of Post-industrial Negative Heritage in Urban Design in China 被引量:3
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作者 廖莹 沈一 《Journal of Landscape Research》 2012年第4期19-21,共3页
Under the background that urban development has been renovated constantly, the paper has analyzed cultural circulation system and recycling effect in urban renovation, and emphasized that traditional culture should be... Under the background that urban development has been renovated constantly, the paper has analyzed cultural circulation system and recycling effect in urban renovation, and emphasized that traditional culture should be extended with industrial heritage as the carrier, so as to transform post- industrial negative heritage into modern civilization adapting to modern life. By taking Beijing "789" for example, its development process and situation have been introduced. Based on the spirit of place, the practical significance of cultural creative park and reuse of industrial heritage have been illustrated. It considers that cultural creation can not only extend cultural context, but also help to find new inspiration in industrial heritage, transforming the function of negative landscape in urban renovation in the form of "catalysis", improving its economic value, social cultural value and cultural effective circulation value. 展开更多
关键词 negATIVE landscape INDUSTRIAL HERITAGE CULTURAL CREATION CULTURAL REGENERATION
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