Highly toxic Aβ begets more Aβ

Alzheimer’s disease(AD)is the most common form of dementia-the 7th leading cause of death worldwide.At the tissue level,AD is characterized by the presence of extracellular amyloid plaques that are comprised primarily of the amyloid-βpeptide(Aβ),and by intraneuronal neurofibrillary tangles composed of tau.Molecular genetics of early-onset AD and longitudinal brain-imaging studies of late-onset AD indicate that extracellular Aβdeposition,in general,precedes neurofibrillary tangle formation in neurons(Hampel et al.,2021;Young-Pearse et al.,2023).

Advancements in Polymer Science: Synthesis, Characterization, and Biomedical Applications of Homopolymers and Copolymers

Polymer science encompasses a different range of materials critical to industries spanning from packaging to biomedicine. Understanding the synthesis, characterization, and applications of common homopolymers and copolymers is fundamental to advancing polymer research and development. In this comprehensive review, we explore various preparation methods, including free radical, anionic, and cationic polymerization, utilized for synthesizing homopolymers and copolymers. Furthermore, we investigate solvent choices commonly employed for polymer characterization, ranging from neat conditions, polar protic and polar aprotic solvents. We also explored characterization techniques, including Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Atomic Force Microscopy (AFM), Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA). In addition to industrial applications, we highlight the diverse biological applications of homopolymers, poly(2-hydroxyethyl methacrylate) (pHEMA) and polystyrene, which find its extensive use in biomedicine. By synthesizing and analyzing this wealth of information, this review aims to provide a comprehensive understanding of the synthesis, characterization, and applications of homopolymers and copolymers, with a particular focus on their biological applications. This holistic approach not only contributes to advancements in polymer science and technology but also fosters innovation in biomedicine, ultimately benefiting human health and well-being.

Synthesis and Characterization of Poly Styrene-Co-Poly 2-Hydroxyethylmethacrylate (HEMA) Copolymer and an Investigation of Free-Radical Copolymerization Propagation Kinetics by Solvent Effects

A series of homo and copolymers of styrene (ST) and 2-hydroxyethyl methacrylate (HEMA) in three different media (bulk, tetrahydrofuran, and benzene) have been investigated by free radical polymerization method. The samples obtained from the synthesis were characterized by Fourier Transform-Infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NMR), atomic force microscopy (AFM), and differential scanning calorimetry (DSC). The results show that the synthesis of the polymers is more feasible under neat conditions rather than solvent directed reaction. Moreover, the DSC data shows that the polystyrene obtained is amorphous in nature and therefore displayed only a glass transition signal rather than crystallization and melting peaks. In addition, this study indicates that homolopolymerization of styrene via free radical polymerization tends to be preferable in less polar solvents like THF than in non-polar solvents like benzene. Benzene might destabilize the formation of the reactive radicals leading to the formation of the products. In summary, the homolpolymerization of styrene is more feasible than the homopolymerization 2-hydroxyethyl methacrylate under the experimental setup used. Styrene is more reactive than 2-hydroxyethyl methacrylate than free radical polymerization reaction due in part of the generation of the benzylic radical intermediate which is more stable leading to the formation of products than alkyl radical which are less stable. Furthermore, polymerization of styrene under neat conditions is preferable in solvent-assisted environments. The choice of solvent for the synthesis of these polymers is crucial and therefore the selection of solvent that leads to the formation of a more stable reaction intermediate is more favorable. It is worth noting that the structure of the proposed copolymer consists of a highly polar and hydrophilic monomer, 2-hydroxyethyl methacrylate and a highly non-polar and hydrophobic monomer, styrene. These functionalities constitute an amphiphilic copolymer with diverse characteristics. A plausible explanation underlying our observations is that the reaction conditions employed in the synthesis of these copolymers might not be the right route required under free radical polymerization.

Facilitators and Barriers to Cervical Cancer Screening among Female Undergraduate Students of Makerere University

There is a higher Human Papilloma Virus peak prevalence in younger women (18 - 25 years) of university age. The undergraduate university students are more at a risk of acquiring cervical cancer because they are at the stage of exploring which predisposes them to risky behavior like early sexual intercourse and multiple sexual partners among others. This creates a need for cervical cancer screening in the population. The facilitators and barriers to cervical cancer screening have been studied in the Ugandan general population but little is known among University students which this study is taking interest. Objective: This study is aimed at determining the facilitators, barriers and background factors associated to cervical cancer screening among female undergraduate students in Makerere University. Methods: Four hundred twenty-two (422) female undergraduate students of Makerere University who fit the eligibility criteria were recruited in this descriptive cross-sectional quantitative study. A self-administered semi structured questionnaire was administered to these participants chosen by convenient sampling. Data collected was analyzed using SPSS version 23 software and logistic regression models was used. Results: Less than a half of (21.1%) of the participants had ever screened for cervical cancer. At multivariate analysis, only year of study and married status were associated to cervical cancer screening with a P-values were of (0.015) and (0.001) with a (1.173 - 4.261) and (1.594 - 6.130) 95% CI respectively. The facilitators agreed upon by participants included: Access to free cervical cancer screening services, adequate knowledge about cervical cancer screening and advice from a friend, family or physician among others. The reported barriers to screening were fear of bad result, low risk perception and fear of embarrassment among others. Conclusions and Recommendations: Among the female undergraduate students of Makerere University, only 21.1% had screened for cervical cancer. Therefore, there is a critical need for university based cancer education campaign on cervical cancer and the benefits of screening. Screening services should be integrated into the existing university medical services.

The Relationship between Dimensions of Emerging Adulthood and Behavioral Problems among Chinese Emerging Adults: The Mediating Role of Physical Activity and Self- Control

Emerging adulthood(EA)is a critical stage of life to develop and sustain a healthy lifestyle,which is also a time of vulnerability to poor physical and mental health outcomes.In this study,we conducted a path analysis(N=1326)to examine associations among four dimensions of EA,levels of regular physical activity(PA),self-control,MPA tendency and irrational procrastination.Results found:1)higher levels of PA predicted both MPA tendency(β=−0.08,95%CI:−0.11 to−0.06,p<0.001)and irrational procrastination(β=−0.01,95%CI:−0.17 to−0.008,p<0.01)indirectly via self-control;2)Instability(β=0.13,95%CI:0.08 to 0.18,p<0.01)and Responsibility(β=−0.06,95%CI:−0.10 to−0.08,p=0.03)exerted direct effects on irrational procrastination and Instability also indirectly predicted irrational procrastination via MPA tendency(β=0.03,95%CI:0.02 to 0.05,p<0.01).These findings proved that perceived features of EA are linked to behavioral problems and supported that regular PA plays a crucial role to protect mental health.

Acceptability of Ambulatory Surgical Services and Its Predictors among Residents of Budondo Sub-County—Jinja District, Uganda

Background: 25% of all people requiring surgical care are not able to access it due to its high cost. These people stand a high risk of preventable severe morbidity and mortality due to poor prognosis of surgically correctable illnesses. Ambulatory surgical care services are significantly cheaper than orthodox surgical care and have become very relevant in this time and age where health conditions that can only be treated with surgical intervention are on the rise. The acceptability of ambulatory surgical care services will determine how this model increases universal health coverage. Objective: To assess the acceptability of ambulatory surgical services and its predictors among residents of Budondo Sub-County—Jinja district. Methods: The study was cross-sectional targeting 371 household heads in Budondo Sub-County, which was stratified by parish, with villages in each randomly sampled. Systematic random sampling was used to sample households and households therein were purposively sampled. Structured interviews and questionnaires were the data collection techniques, and data was analyzed in SPSS version 25 using descriptive statistics and a binomial logit model. Results: The level of acceptability of ambulatory surgical care services among residents of Budondo Sub-County was found to be near-universal, at 96.5%. The odds of accepting ambulatory surgical care were least among household heads who agreed that surgery done in a hospital would be cheaper than surgery done at community level (aOR = 0.174 [CI = 0.055 - 0.553]), those who had health insurance (aOR = 0.105 [95% CI = 0.030 - 0.371]), and household heads who were covered with private health insurance (aOR = 0.078 [95% CI = 0.008 - 0.792]). Acceptability of ASC was higher among household heads who agreed that they would trust ambulatory surgical centers with their life were more likely to accept ambulatory surgical care (aOR = 1.124, [95% CI = 1.122 - 3.218], P = 0.000), and household heads from households that had less than five members with surgery history were twice as likely to accept ambulatory surgical care (aOR = 2.431 [95% CI = 1.122 - 5.898], P = 0.000). Conclusion: Acceptability of ambulatory surgical care services among residents of Budondo Sub-County is high, and near-universal. It is mainly predicted by intrapersonal correlates and to a small extent by socio-demographic characteristics, with the implication that the administration of Global Surgical Initiatives in Kyabirwa ought to focus on modifying or uphold the intrapersonal characteristics found to be antagonists and protagonists of acceptability, respectively.

Investigation into Recent Temperature and Rainfall Trends in Mali Using Mann-Kendall Trend Test: Case Study of Bamako

Rainfall and temperature variability analysis is important for researchers and policy formulators in making critical decisions on water availability and use in communities. The Western Sahel, which comprises Mali is considered as one of the vulnerable regions to climate change, and also encountered the challenges of climatic shocks such as flood and drought. This research therefore sought to investigate climate change effects on hydrological events and trends in Sahelian rainfall intensity using Bamako (Mali) as a case study from 1991 to 2020, as limited data availability did not allow an extended period of study. Monthly observed data provided by MALI-METEO was used to validate daily rainfalls data from African Rainfall Climatology Version 2 (ARC2) satellite-based rainfall product on monthly basis. The validated model performance used Nash-Sutcliffe Efficiency (NSE) and Percent Bias (PBAIS) and gave results of 0.904 and 1.0506 respectively. Trends in annual maximum temperatures and rainfalls were analyzed using Mann-Kendall trend test. The result indicated that the trend in annual maximum rainfalls was decreasing, while annual total rainfall was increasing but not significant at 5% significance level. The rate of increase in annual total rainfalls was 0.475 mm/year according to the observed annual rainfall series and decreased to 0.68 mm/year in annual maximum. The analysis further found that annual maximum temperatures were increasing at the rate of 0.03°C/year at 5% significance level. To provide more accurate climate predictions, it is recommended that further studies on rainfall and temperature with data sets spanning 60 - 90 years be carried out.

Meteorological Drought Detection and Forecast Using Standardized Precipitation Index and Univariate Distribution Models: Case Study of Bamako, Mali

As an extended period of unusually dry weather conditions without sufficient rain, drought poses enormous risk on societies. Characterized by the absence of precipitation for long periods of time, often resulting in water scarcity, droughts are increasingly posing significant environmental challenges. Drought is therefore considered an important element in the management of water resources, especially groundwater resources during drought. This study therefore sought to investigate the rainfall variability and the frequency of drought for the period 1991 to 2020 in Bamako based on monthly rainfall data from Bamako-Senou gauge station. The standardized precipitation index (SPI) for 12-month, 6-month and 3-month timescales and the SPI for annual totals were used to characterized drought in the study area (Bamako). Univariate parametric probability distributions such as Normal, Log-normal, Gumbel type I and Pearson type III (P3) distributions were fitted with drought variables (severity and duration) for future planning and management. Non-parametric test such as Mann-Kendall trend test was also used to detect trend in annual rainfall data. The results showed that based on 12-month SPI, Bamako experienced two (02) extreme droughts one in July 2002 (SPI = -2.2165) and another in June 2015 (SPI = -2.0598 QUOTE SPI=-2.0598 ). Drought years represented 46.67% for the overall periods according to the SPI for annual totals. The result further indicated that based on the goodness of fit test, the P3 distribution represents the best fitted distribution to both drought severity and duration over Bamako. Bamako is expected to experience several severe severities with higher and shorter duration in the future. Severities with 1, 2, 6, and 10-month duration had return periods ranged from 2.4 to 3.8 years, while 5, 10, 20, 25, 50, and 100-year return periods had 18.51, 26.08, 33.25, 35.50, 42.38, and 49.14 severities, respectively, and durations associated to these severities were 19.8, 26.9, 33.5, 35.6, 42, and 48.2 months, respectively.

Energy Consumption Analysis and Characterization of Aerospace Manufacturing Facilities in the United States–A Step towards Sustainable Development

In this study,information on energy usage in the United States(U.S.)aerospace manufacturing sector has been analyzed and then represented as energy intensities(kWh/m2)to establish benchmark data and to compare facilities of varying sizes.First,public sources were identified and the data from these previously published sources were aggregated to determine the energy usage of aerospace manufacturing facilities within the U.S.From this dataset,a sample of 28 buildings were selected and the energy intensity for each building was estimated from the data.Next,as a part of this study the energy data for three additional aerospace manufacturing facilities in the U.S.were collected firsthand.That data was analyzed and the energy intensity(kWh/m2)for each facility was calculated and then compared with the energy intensities of the 28 buildings from the sample.Three different indicators of energy consumption in aerospace manufacturing facilities were used as comparators to assist facility managers with determining potential energy savings and help in the decision-making process.On average,aerospace manufacturing facilities in the United States spent 4 cents for each dollar of sale on energy.The energy intensity(kWh/m2)and the power intensity(W/m2)for each facility were calculated based on the actual facility energy bills.The power intensity for these facilities ranges from 34 to 134 W/m2.The energy intensity ranged from 232 to 949 kWh/m2.We found that the power intensity could be used to estimate energy consumption when the annual operating hours of the facility are considered.and to estimate the energy-related carbon dioxide emissions.

Anti-Mycobacterial Activity of Medicinal Plant Extracts Used in the Treatment of Tuberculosis by Traditional Medicine Practitioners in Uganda

Tuberculosis (TB) remains a public health challenge and one of the leading causes of death worldwide. TB is preventable and curable. However, treatment of tuberculosis has continued to be difficult as a result of rapid increase of multidrug and extensively drug resistant strains of Mycobacterium tuberculosis. Medicinal plants have for centuries been traditionally used in treatment of tuberculosis and similar ailments. They possess antimicrobial properties which render them a new hope as a source of novel bioactive leads in the development of antimycobacterial agents. In this study, 2 plant species commonly used traditionally in Uganda for treatment of tuberculosis, Zanthoxylum leprieurii and Rubia cordifolia were screened for in vitro antimycobacterial activity against Mycobacterium tuberculosis strains;pan sensitive MTB H37Rv, Rifampicin resistant TMC 331 strain and two wild strains (one rifampicin resistant and another one rifampicin susceptible). Antimycobacterial activity of aqueous, ethanolic and methanolic plant extracts was determined using Resazurin Microtiter Assay (REMA). Both plant extracts exhibited significant in vitro antimycobacterial activity against all strains of Mycobacterium tuberculosis. Minimum inhibitory concentrations (MIC) of methanolic crude extracts of both plants ranged from 23.4 μg/mL to 187.5 μg/mL. Comparatively, methanol extracts of both plants possessed superior antimycobacterial activity against all Mycobacterium tuberculosis strains. Our findings indicated that both plants exhibited activity against susceptible and resistant strains of Mycobacterium tuberculosis. While antimycobacterial activity of Z. leprieurii confirms results from previous studies, activity of the extracts of R. cordifolia is reported for the first time in East Africa. Further studies aimed at determining the effects of combination of these plant extracts and standard anti-TB drugs should be carried out.

glipr1基因的原核表达及多克隆抗体制备

目的克隆表达胶质瘤致病相关蛋白1基因(glipr1)并制备多克隆抗体,运用该抗体检测各肿瘤细胞系中GLIPR1的表达。方法通过PCR技术以含glipr1基因的c DNA克隆质粒(p LX304-glipr1)为模板获得glipr1(M)片段,再将此片段克隆至表达载体p ET-15b上,并转入大肠杆菌BL21-Codon Plus(DE3)进行表达;Ni柱纯化后的GLIPR1(M)蛋白作为抗原免疫家兔,获得多克隆抗体,Western blot法检测其特异性,并检测GLIPR1在A549、PC14、LNCa P、PC3及U87细胞中的表达。结果成功构建了表达载体p ET-15bglipr1(M),并获得了纯化的GLIPR1(M)蛋白,成功制备了兔抗GLIPR1多克隆抗体,特异性高,可用于检测各细胞系中GLIPR1的表达,GLIPR1在U87中的表达最高。结论成功表达了GLIPR1(M)蛋白,并获得了多克隆抗体,为进一步研究GLIPR1的功能和作用机制奠定了基础。

层流区Shields曲线分布规律试验

为探明层流条件下Shields曲线的分布规律,运用电荷耦合组件(Charge Coupled Device,CCD)成像技术结合激光扫描及计算机图像处理技术,在水和甘油混合液中对无黏性均匀玻璃颗粒的起动拖曳力进行测量,并根据层流绕流理论建立了无黏性均匀颗粒的滚动起动模型,提出层流条件下无黏性均匀颗粒的量纲一起动拖曳力公式。试验观测发现在层流范围内希尔兹数呈规则的带状分布,流体作用引起颗粒床表面粗化并导致床面颗粒突起减小,使颗粒起动拖曳力增大1倍以上。结果表明颗粒床表面结构性状直接影响着颗粒起动拖曳力的大小,在层流区Shields曲线具有带状分布特性。

微波辐射促进的3-烷基取代咪唑并[1,5-a]吡啶合成

分别在常规加热和微波辐射条件下,由双(2-吡啶甲酰)、二(2-吡啶)甲酮与脂肪醛及醋酸铵在醋酸溶剂中反应成功地制备了3-烷基取代的咪唑并[1,5-a]吡啶.实验结果表明:微波法比传统的合成方法产率高、反应时间短.产物的结构经过1HNMR,MS和元素分析表征.

Vascular endothelial growth factor A, secreted in response to transforming growth factor-β1 under hypoxic conditions, induces autocrine effects on migration of prostate cancer cells

Hypoxia and transforming growth factor-β1 （TGF-β1） increase vascular endothelial growth factor A （VEGFA） expression in a number of malignancies. This effect of hypoxia and TGF-β1 might be responsible for tumor progression and metastasis of advanced prostate cancer. In the present study, TGF-β1 was shown to induce VEGFA165 secretion from both normal cell lines （HPV7 and RWPE1） and prostate cancer cell lines （DU 145 and PC3）. Conversely, hypoxia-stimulated VEGFA165 secretion was observed only in prostate cancer cell lines. Hypoxia induced TGF-β1 expression in PC3 prostate cancer cells, and the TGF-β1 type I receptor （ALK5） kinase inhibitor partially blocked hypoxia-mediated VEGFA16s secretion. This effect of hypoxia provides a novel mechanism to increase VEGFA expression in prostate cancer cells. Although autocrine signaling of VEGFA has been implicated in prostate cancer progression and metastasis, the associated mechanism is poorly characterized. VEGFA activity is mediated via VEGF receptor （VEGFR） 1 （Fit-l） and 2 （FIk-I/KDR）. Whereas VEGFR-1 mRNA was detected in normal prostate epithelial cells, VEGFR-2 mRNA and VEGFR protein were expressed only in PC3 cells. VEGFA165 treatment induced phosphorylation of extracellular signal-regulated kinase 1/2 （ERKI/2） in PC3 cells but not in HPV7 cells, suggesting that the autocrine function of VEGFA may be uniquely associated with prostate cancer. Activation of VEGFR-2 by VEGFA165 was shown to enhance migration of PC3 cells. A similar effect was also observed with endogenous VEGFA induced by TGF-β1 and hypoxia. These findings illustrate that an autocrine loop of VEGFA via VEGFR-2 is critical for the tumorigenic effects of TGF-β1 and hypoxia on metastatic prostate cancers.

风险和临界状态:区域性环境退化的轨迹

1987年世界环境与发展委员会的报告中要求进行全球性的风险评估项目,以支持和扩大联合国环境规划署的工作。本文主要报告了集中在美国克拉克大学进行的一项国际性研究项目。该项目研究了分布在世界不同区域的9个地区在过去50～70年里不断增强的环境风险的原因和后果。这9个地区分别是:亚马孙、东南亚的东巽他地区、肯尼亚东南部的乌坎巴尼地区、尼泊尔中部山区、中国的鄂尔多斯高原、咸海、美国南部高地平原、墨西哥城区和北海。作者从临界状态的概念及其还在完善中的定义和环境受威胁的地区分类着手论述。对9个地区均组建了研究小组并进行了研究。在本文中,作者回顾了研究中所应用的概念和方法的制定以及在已获得的重要研究结果。研究人员认为,在研究地区迅速增大的环境退化速率与社会对此反应迟缓之间存在越来越大的脱节,存在着环境退化的威胁、后代选择权的丧失,以及在取代资源利用和减轻风险方面的代价日益增大的问题。

Predicting the daily return direction of the stock market using hybrid machine learning algorithms

Big data analytic techniques associated with machine learning algorithms are playing an increasingly important role in various application fields,including stock market investment.However,few studies have focused on forecasting daily stock market returns,especially when using powerful machine learning techniques,such as deep neural networks(DNNs),to perform the analyses.DNNs employ various deep learning algorithms based on the combination of network structure,activation function,and model parameters,with their performance depending on the format of the data representation.This paper presents a comprehensive big data analytics process to predict the daily return direction of the SPDR S&P 500 ETF(ticker symbol:SPY)based on 60 financial and economic features.DNNs and traditional artificial neural networks(ANNs)are then deployed over the entire preprocessed but untransformed dataset,along with two datasets transformed via principal component analysis(PCA),to predict the daily direction of future stock market index returns.While controlling for overfitting,a pattern for the classification accuracy of the DNNs is detected and demonstrated as the number of the hidden layers increases gradually from 12 to 1000.Moreover,a set of hypothesis testing procedures are implemented on the classification,and the simulation results show that the DNNs using two PCA-represented datasets give significantly higher classification accuracy than those using the entire untransformed dataset,as well as several other hybrid machine learning algorithms.In addition,the trading strategies guided by the DNN classification process based on PCA-represented data perform slightly better than the others tested,including in a comparison against two standard benchmarks.

中国文化产业金融投资前景分析

文化产业是21世纪的朝阳产业,是文化与经济相结合的产品,具有优结构、扩消费、增就业、促跨越、可持续的独特优势,其业务范围大,产品延伸链条长,值得投资。我国政府出台了加快发展文化产业的战略决策,为文化产业金融投资开放了广阔天地,是金融投资的好机会。全球金融危机为文化产业创造了发展良机,它将为我国经济复苏提供强劲动力。

Improved simulation of carbon and water fluxes by assimilating multi-layer soil temperature and moisture into process-based biogeochemical model

Background: Soil temperature and moisture are sensitive indicators in soil organic matter decomposition because they control global carbon and water cycles and their potential feedback to climatic variations. Although the Biome-Biogeochemical Cycles (Biome-BGC) model is broadly applied in simulating forest carbon and water fluxes, its single-layer soil module cannot represent vertical variations in soil moisture. This study introduces the Biome-BGC MuSo model, which is composed of a multi-layer soil module and new modules pertaining to phenology and management for simulations of carbon and water fluxes. Although this model considers soil processes among active layers, estimates of soil-related variables might be biased, leading to inaccurate estimates of carbon and water fluxes. Methods: To improve the estimations of soil-related processes in Biome-BGC MuSo, this study assimilates ground-measured multi-layer daily soil temperature and moisture at the Changbai Mountains forest flux site by using the Ensemble Kalman Filter algorithm. The modeled estimates of water and carbon fluxes were evaluated with measurements using determination coefficient (R2) and root mean square error (RMSE). The differences in the RMSEs from Biome-BGC MuSo and the assimilated Biome-BGC MuSo were calculated (ΔRMSE), and the relationships between ΔRMSE and the climatic and biophysical factors were analyzed. Results: Compared with the original Biome-BGC model, Biome-BGC MuSo improved the simulations of ecosystem respiration (ER), net ecosystem exchange (NEE) and evapotranspiration (ET). Data assimilation of the soil-related variables into Biome-BGC MuSo in real time improved the accuracies of the simulated carbon and water fluxes (ET: R^2=0.81, RMSE=0.70 mm·d^-1;ER: R^2=0.85, RMSE=1.97 gC·m^-2·d^-1;NEE: R^2=0.70, RMSE=1.16 gC·m^-2·d^-1). Conclusions: This study proved that seasonal simulation of carbon and water fluxes are more accurate when using Biome-BGC MuSo with a multi-layer soil module than using Biome-BGC with a single-layer soil module. Moreover, assimilating the observed soil temperature and moisture data into Biome-BGC MuSo improved the modeled estimates of water and carbon fluxes via calibrated soil-related simulations. The assimilation strategy is applicable to various climatic and biophysical conditions, particularly densely forested areas, and for local or regional simulation.

Lessons Learned from Aquifer Storage and Recovery (ASR) Systems in the United States

This paper is the result of a survey and analyses of available data from 204 Aquifer Storage and Recovery (ASR) sites in the United States. This ASR site survey included all active and inactive sites and collected both operational and construction details. The inactive sites are of particular interest here because these are the projects from which valuable lessons can often be learned. The intent of this paper is to examine the reasons for those projects that are terminated. Statistical analyses indicated that there were factors associated with terminated ASR projects: general geographic location (e.g., region), operational issue, storage cycle, casing material, and injection formation. The injection formation involves local geology and aquifer characteristics (i.e., whether the aquifer is leaky and/or unconfined, and if water can be displaced to surface water bodies or adjacent aquifers). Operational problems associated with inactive projects include well clogging, metals mobilization, a low percentage of recovery for injected water, and disinfection byproducts in the recovered water.

美国与德国隐私信息立法与政策框架的比较

比较研究了美国与德国隐私信息方面的立法与政策,发现两国在保护隐私信息方法上的显著不同。美国认为自我监管与部门化监管的方法有助于建立透明的法律环境;此外,美国立法强调保护公共单位所持有的个人信息,而对私有单位及其对个人信息的采集、存储、使用和传递没有过多限制。而在德国,法律统一限定了私有部门和公有部门对个人信息的采集、使用和传递,并由一个机构监管执行,这些差异并没有随全球电子化市场的发展而减少。