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 primaril...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).展开更多
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 sa...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 (<sup>1</sup>H 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.展开更多
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...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. <strong>Objective: </strong>This study is aimed at determining the facilitators, barriers and background factors associated to cervical cancer screening among female undergraduate students in Makerere University. <strong>Methods: </strong>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. <strong>Results:</strong> 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. <strong>Conclusions and Recommendations: </strong>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.展开更多
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 co...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.展开更多
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 c...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.展开更多
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 w...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.展开更多
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 facilit...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.展开更多
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...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.展开更多
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 rapi...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.展开更多
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 ...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.展开更多
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 f...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.展开更多
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...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.展开更多
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 bot...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.展开更多
基金supported by the National Institutes of Health through grant R15AG055043 to NDL and also by the Lise Ann and Leo Beaver’s endowment to Clark University.
文摘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).
文摘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 (<sup>1</sup>H 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.
文摘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. <strong>Objective: </strong>This study is aimed at determining the facilitators, barriers and background factors associated to cervical cancer screening among female undergraduate students in Makerere University. <strong>Methods: </strong>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. <strong>Results:</strong> 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. <strong>Conclusions and Recommendations: </strong>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.
文摘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.
文摘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.
文摘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.
文摘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.
基金the Start-Up Research Grant of Shenzhen University[20200807163056003]the Start-Up Research Grant[Peacock Plan:20191105534C].
文摘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.
文摘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.
文摘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.
文摘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.
基金supported by the Fundamental Research Funds for the Central Non-profit Research Institution of CAF under grant CAFYBB2017QC005General Financial Grant from the China Postdoctoral Science Foundation(2017M611036)+1 种基金National Natural Science Foundation of China(Grant No.41771392)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA19030302)
文摘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.
文摘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.