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
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 t...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 betweenΔRMSE 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
A pot experiment was conducted to investigate the heavy metal accumulation in maize (Zea mays L.) plant grown in chromated copper arsenate (CCA) soil amended with treated composted sewage biosolid. The initial concent...A pot experiment was conducted to investigate the heavy metal accumulation in maize (Zea mays L.) plant grown in chromated copper arsenate (CCA) soil amended with treated composted sewage biosolid. The initial concentrations of chromium, copper, arsenate in the CCA soil and sewage biosolid were determined by atomic absorption spectrophotometer. These were found to be, in CCA soil: 365.8 ± 6.18, 109.22 ± 14.04, 28.22 ± 3.8 and in sewage biosolid: 35 ± 1.06, 1.0 ± 0.02, 0 mg·kg-1 respectively. The concentration of Cr, Cu and As determined in both the roots and shoots generally decreased with increase in percentage amendment concentration and number of days (20 and 40 days after planting). At 20 days, the total metal concentration ranges in roots were As (5.54 ± 0.03 - 6.69 ± 1.14), Cr (9.59 ± 0.02 - 13.22 ± 0.03), Cu (2.28 ± 0.06 - 4.53 ± 0.37) mg·kg-1 while at 40 days the values were As (5.60 ± 0.19 - 6.08 ± 0.01), Cr (9.47 ± 0.04 - 10.95 ± 0.09), Cu (3.94 ± 0.19 - 4.64 ± 0.07) mg·kg-1. For the shoot system, the concentrations of the metals at 20 days were As (5.28 ± 0.03 - 5.90 ± 0.13), Cr (9.30 ± 0.05 - 10.07 ± 0.06), Cu (3.64 ± 0.12 - 4.72 ± 0.15) mg/kg while at 40 days the values obtained were As (5.28 ± 0.03 - 5.9 ± 0.13), Cr (9.69 ± 0.14 - 10.07 ± 0.03), Cu (2.94 ± 0.72 - 4.53 ± 0.03) mg·kg-1. The roots accumulated the three heavy metals more than the shoot system at all treatments used. Concentration of arsenic, chromium and copper in the plants decreased with increasing percentage amendments. The results suggest relatively low bioavailability of the three metals in CCA soil treated with high percentages of sewage biosolid as an amendment.展开更多
Background: Late antenatal care attendance among pregnant women at health facilities remains a significant public health problem. Globally, approximately 830 women die every day due to pregnancy-related complications ...Background: Late antenatal care attendance among pregnant women at health facilities remains a significant public health problem. Globally, approximately 830 women die every day due to pregnancy-related complications and 99% of these deaths occur in developing countries whereby 86% of pregnant women access Antenatal Care (ANC) services at least once. Objective: The general objective of the study was to determine factors associated with late antenatal care seeking behavior among pregnant women at Kyenjojo general hospital. Methods: This was a descriptive cross sectional study design that considered quantitative data collection methods among pregnant women attending ANC. The sample size was determined using Kish and Leslie (1969) formula using a proportion of 37% (0.37) of women who sought late ANC. A systematic sampling technique was used to sample pregnant women on daily basis. Results: A total of 283 women participated in the study. Spouse’s occupation was significantly associated with late ANC attendance (p = 0.026). On the other hand, education level of respondent (Fisher’s = 8.363, p = 0.028*), religion (Fisher’s = 5.77, p = 0.048*) and parity (Fisher’s 10.312, p = 0.026*) revealed statistically significant association with late ANC attendance. In multivariate logistic regression, on occupation, women with unemployed spouses were significantly associated with 25% increase in attendance of late ANC compared to those in formal employment (AOR = 0.25, CI: 0.073 - 0.855, p = 0.027*). Conclusion: The Majority of pregnant women sought ANC at 90.1% (n = 255). There’s a need for government to strengthen health promotion targeting women in rural communities.展开更多
The designed synthesis of chiral covalent organic frameworks(COFs) featuring intriguing properties is fairly scant and remains a daunting synthetic challenge.Here we develop a de novo synthesis of an enantiomeric pair...The designed synthesis of chiral covalent organic frameworks(COFs) featuring intriguing properties is fairly scant and remains a daunting synthetic challenge.Here we develop a de novo synthesis of an enantiomeric pair of 2 D hydroxyl-functionalized hydrazone-linked chiral COFs,(S)-and(R)-HthBta-OH COFs,using enantiopure 2,5-bis(2-hydroxypropoxy)terephthalohydrazide(Hth) as monomers.The fo rmation process of hydroxyl-functionalized chiral COFs was monitored using rigorous time-dependent PXRD,vibrational circular dichroism(VCD),and electronic circular dichroism(ECD) studies.Remarkably,VCD spectra indicated a unique chiral signal inversion from the positive Cotton effect of(S)-Hth monomer to the negative Cotton effect of(S)-HthBta-OH COF,which has never been reported in chiral COFs.Moreover,two unprecedented carboxyl-functionalized chiral COFs,(S)-and(R)-HthBta-COOH,were constructed by a post-synthetic modification of the corresponding hydroxyl chiral COFs with succinic anhydride.Notably,carboxyl-functionalized COFs retained homochirality and crystallinity without linker racemization and structural collapse after the chemical modification due to the chemically robust nature of pristine hydrazone-linked chiral COFs.展开更多
Human society locally and globally needs to better understand and respond to ever-more complex, interwoven problems: environmental degradation;climate instability;persistent poverty;disparities in human health;growing...Human society locally and globally needs to better understand and respond to ever-more complex, interwoven problems: environmental degradation;climate instability;persistent poverty;disparities in human health;growing income/wealth inequality;economies and infrastructures vulnerable to climate shock;and mounting socio-political unrest. Cities are where most people live, urbanization is a strong upward global trend, and cities bring all these problems into sharp, compelling focus. Since outcomes stem from processes and systems, we argue transformative changes depend on re-imagining the Urban Design, Urban Planning and Urban Development Practice (UD/UP/UDP) process. While there has been insufficient attention to process innovation— with technological aspects tending to dominate UD/UP/UDP work—emerging systems views of cities, and disenchantment with existing modes are enabling. We propose an empirically based integrative frame to tackle recognized conundrums, and inform an adaptive UD/UP/UDP process—from concept through design, assessment, planning, implementation, project functioning and monitoring. The frame contemplates six domains (6-D): 1) Project ethos, concept, and framing;2) sectors, topics, and issues;3) Varying spatial and temporal scales;4) Stakeholder interests, relationships and capacities;5) Knowledge types, modes and methods;and 6) Socio-technical capacities and networks. The frame, process and outcomes constitute a socio-technical enterprise (STE) approach to UD/UP/UDP work, with implications for education, training, and professional practice. We highlight the pivotal role Integrators and Universities play, and the scalability of STE knowledge/capacity networks. The case of Greater Mexico City/Central Mexico Urban Region illustrates the utility of the approach in a hyper-complex, climate-change vulnerable regional context.展开更多
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that regulates a battery of genes in response to exposure to a broad class of environmental poly aromatic hydrocarbons (PAH). AhR is histo...The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that regulates a battery of genes in response to exposure to a broad class of environmental poly aromatic hydrocarbons (PAH). AhR is historically characterized for its role in mediating the toxicity and adaptive responses to these chemicals, however mounting evidence has established a role for it in ligand-independent physiological processes and pathological conditions, including cancer. The AhR is overexpressed and constitutively activated in advanced breast cancer cases and was shown to drive the progression of breast cancer. In this article we will review the current state of knowledge on the possible role of AhR in breast cancer and how it will be exploited in targeting AhR for breast cancer therapy.展开更多
基金supported by NIGMS(SC1GM140907 to G.-Y.L.)the Prostate Cancer Research Racial Disparity Grant from the Prostate Cancer Research(PCR)in the United Kingdom(grant reference[5001],to G.-Y.L.)the AU Medical Center,Inc.with a Grant/Contract Number CAU-AU Partnership-Kavuri-Liou and by NIMHDsupported Research Capacity Core at CAU(U54MD007590)。
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 betweenΔRMSE 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.
文摘A pot experiment was conducted to investigate the heavy metal accumulation in maize (Zea mays L.) plant grown in chromated copper arsenate (CCA) soil amended with treated composted sewage biosolid. The initial concentrations of chromium, copper, arsenate in the CCA soil and sewage biosolid were determined by atomic absorption spectrophotometer. These were found to be, in CCA soil: 365.8 ± 6.18, 109.22 ± 14.04, 28.22 ± 3.8 and in sewage biosolid: 35 ± 1.06, 1.0 ± 0.02, 0 mg·kg-1 respectively. The concentration of Cr, Cu and As determined in both the roots and shoots generally decreased with increase in percentage amendment concentration and number of days (20 and 40 days after planting). At 20 days, the total metal concentration ranges in roots were As (5.54 ± 0.03 - 6.69 ± 1.14), Cr (9.59 ± 0.02 - 13.22 ± 0.03), Cu (2.28 ± 0.06 - 4.53 ± 0.37) mg·kg-1 while at 40 days the values were As (5.60 ± 0.19 - 6.08 ± 0.01), Cr (9.47 ± 0.04 - 10.95 ± 0.09), Cu (3.94 ± 0.19 - 4.64 ± 0.07) mg·kg-1. For the shoot system, the concentrations of the metals at 20 days were As (5.28 ± 0.03 - 5.90 ± 0.13), Cr (9.30 ± 0.05 - 10.07 ± 0.06), Cu (3.64 ± 0.12 - 4.72 ± 0.15) mg/kg while at 40 days the values obtained were As (5.28 ± 0.03 - 5.9 ± 0.13), Cr (9.69 ± 0.14 - 10.07 ± 0.03), Cu (2.94 ± 0.72 - 4.53 ± 0.03) mg·kg-1. The roots accumulated the three heavy metals more than the shoot system at all treatments used. Concentration of arsenic, chromium and copper in the plants decreased with increasing percentage amendments. The results suggest relatively low bioavailability of the three metals in CCA soil treated with high percentages of sewage biosolid as an amendment.
文摘Background: Late antenatal care attendance among pregnant women at health facilities remains a significant public health problem. Globally, approximately 830 women die every day due to pregnancy-related complications and 99% of these deaths occur in developing countries whereby 86% of pregnant women access Antenatal Care (ANC) services at least once. Objective: The general objective of the study was to determine factors associated with late antenatal care seeking behavior among pregnant women at Kyenjojo general hospital. Methods: This was a descriptive cross sectional study design that considered quantitative data collection methods among pregnant women attending ANC. The sample size was determined using Kish and Leslie (1969) formula using a proportion of 37% (0.37) of women who sought late ANC. A systematic sampling technique was used to sample pregnant women on daily basis. Results: A total of 283 women participated in the study. Spouse’s occupation was significantly associated with late ANC attendance (p = 0.026). On the other hand, education level of respondent (Fisher’s = 8.363, p = 0.028*), religion (Fisher’s = 5.77, p = 0.048*) and parity (Fisher’s 10.312, p = 0.026*) revealed statistically significant association with late ANC attendance. In multivariate logistic regression, on occupation, women with unemployed spouses were significantly associated with 25% increase in attendance of late ANC compared to those in formal employment (AOR = 0.25, CI: 0.073 - 0.855, p = 0.027*). Conclusion: The Majority of pregnant women sought ANC at 90.1% (n = 255). There’s a need for government to strengthen health promotion targeting women in rural communities.
基金We are grateful for the financial support from the National Natural Science Foundation of China(Nos.21603076 and 21571070)the Natural Science Foundation of Guangdong Province(No.2018A030313193).
文摘The designed synthesis of chiral covalent organic frameworks(COFs) featuring intriguing properties is fairly scant and remains a daunting synthetic challenge.Here we develop a de novo synthesis of an enantiomeric pair of 2 D hydroxyl-functionalized hydrazone-linked chiral COFs,(S)-and(R)-HthBta-OH COFs,using enantiopure 2,5-bis(2-hydroxypropoxy)terephthalohydrazide(Hth) as monomers.The fo rmation process of hydroxyl-functionalized chiral COFs was monitored using rigorous time-dependent PXRD,vibrational circular dichroism(VCD),and electronic circular dichroism(ECD) studies.Remarkably,VCD spectra indicated a unique chiral signal inversion from the positive Cotton effect of(S)-Hth monomer to the negative Cotton effect of(S)-HthBta-OH COF,which has never been reported in chiral COFs.Moreover,two unprecedented carboxyl-functionalized chiral COFs,(S)-and(R)-HthBta-COOH,were constructed by a post-synthetic modification of the corresponding hydroxyl chiral COFs with succinic anhydride.Notably,carboxyl-functionalized COFs retained homochirality and crystallinity without linker racemization and structural collapse after the chemical modification due to the chemically robust nature of pristine hydrazone-linked chiral COFs.
文摘Human society locally and globally needs to better understand and respond to ever-more complex, interwoven problems: environmental degradation;climate instability;persistent poverty;disparities in human health;growing income/wealth inequality;economies and infrastructures vulnerable to climate shock;and mounting socio-political unrest. Cities are where most people live, urbanization is a strong upward global trend, and cities bring all these problems into sharp, compelling focus. Since outcomes stem from processes and systems, we argue transformative changes depend on re-imagining the Urban Design, Urban Planning and Urban Development Practice (UD/UP/UDP) process. While there has been insufficient attention to process innovation— with technological aspects tending to dominate UD/UP/UDP work—emerging systems views of cities, and disenchantment with existing modes are enabling. We propose an empirically based integrative frame to tackle recognized conundrums, and inform an adaptive UD/UP/UDP process—from concept through design, assessment, planning, implementation, project functioning and monitoring. The frame contemplates six domains (6-D): 1) Project ethos, concept, and framing;2) sectors, topics, and issues;3) Varying spatial and temporal scales;4) Stakeholder interests, relationships and capacities;5) Knowledge types, modes and methods;and 6) Socio-technical capacities and networks. The frame, process and outcomes constitute a socio-technical enterprise (STE) approach to UD/UP/UDP work, with implications for education, training, and professional practice. We highlight the pivotal role Integrators and Universities play, and the scalability of STE knowledge/capacity networks. The case of Greater Mexico City/Central Mexico Urban Region illustrates the utility of the approach in a hyper-complex, climate-change vulnerable regional context.
文摘The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that regulates a battery of genes in response to exposure to a broad class of environmental poly aromatic hydrocarbons (PAH). AhR is historically characterized for its role in mediating the toxicity and adaptive responses to these chemicals, however mounting evidence has established a role for it in ligand-independent physiological processes and pathological conditions, including cancer. The AhR is overexpressed and constitutively activated in advanced breast cancer cases and was shown to drive the progression of breast cancer. In this article we will review the current state of knowledge on the possible role of AhR in breast cancer and how it will be exploited in targeting AhR for breast cancer therapy.