Miracle-dz/UniFAR-FTUs huggingface dataset:
Three-decade changes in chemical composition of precipitation in Guangzhou city, southern China: has precipitation recovered from acidification following sulphur dioxide emission control?

We examined if precipitation had recovered from acidification in Guangzhou, the third biggest city in China, and if sulphur deposition in precipitation had decreased, and to what extent if yes, following abatement strategies in sulphur dioxide (SO2) emission and energy use implemented since 2001. SO2 emissions were decreasing steadily since 2001, but a marked recovery of precipitation acidity occurred only since 2005; precipitation pH values decreased from 4.65 in 2001 to 4.34 in 2005 and then increased to 5.08 in 2010, while in the same period acid rain (pH<5.6) frequency increased from 70% to 81% and then decreased to 48%. During this period, the change in pH value and sulphate concentration more reflected the patterns of SO2 emission at provincial and national scales than at the local scale, suggesting that precipitation chemical composition was largely controlled by the emissions of pollutants from surrounding areas of the study city. Since 2001, sulphate deposition in precipitation decreased significantly (by 40%) but nitrogen deposition remained unaltered. More importantly, the current sulphur (43 kg S ha−1 yr−1 as sulphate) and nitrogen depositions (35 kg N ha−1 yr−1 as ammonium plus nitrate in 2010) were still among the highest in China. These results highlight the fact that ambient sulphur and nitrogen deposition still pose a threat to the health of both terrestrial and aquatic ecosystems. Precipitation may become more acidified in the future because the deposition of alkaline dusts containing calcium is also likely to decrease with stricter SO2 emission control policy and reduced construction activities. Additionally, we recommend that a reduction of emissions of nitrogen and chlorine bearing pollutants is urgently required for complete control on acid deposition.
Depressive symptoms and cardiovascular disease: a population-based study of older adults in rural Burkina Faso

Objectives To contribute to the current understanding of depressive disorders in sub-Saharan African (SSA) countries by examining the association of depressive symptoms with cardiovascular and cardiometabolic conditions in a population-based study of middle-aged and older adults in rural Burkina Faso. Setting This study was conducted in the Nouna Health and Demographic Surveillance System in north-western Burkina Faso, in a mixed rural and small-town environment. The data were obtained between May and July 2018. Participants Consenting adults over 40 years of age (n=3026). Primary and secondary outcome measures Depressive symptoms were assessed using the Patient Health Questionnaire depression module (PHQ-9). Chronic cardiometabolic conditions were assessed via a lipid panel and glycated haemoglobin measures from serum, alongside anthropometry and blood pressure measurements and a self-reported questionnaire. Multivariable linear regression was used to test the relationship between depressive symptoms and cardiovascular/cardiometabolic conditions after controlling for sociodemographic factors. Results Depressive symptoms were not associated with the metabolic syndrome (standardised beta coefficient=0.00 (95% CI −0.04 to 0.03)), hypertension (beta=0.01 (95% CI −0.02 to 0.05)), diabetes mellitus (beta=0.00 (95% CI −0.04 to 0.04)) and past diagnosis of elevated blood pressure or blood sugar. Prior stroke diagnosis (beta=0.04 (95% CI 0.01 to 0.07)) or heart disease (beta=0.08 (95% CI 0.05 to 0.11)) was positively associated with the standardised PHQ-9 score as were self-reported stroke symptoms. Conclusion Objectively measured cardiometabolic conditions had no significant association with depressive symptoms in an older, poor, rural SSA population, in contrast to observations in high income countries. However, consequences of cardiovascular disease such as stroke and heart attack were associated with depressive symptoms in older adults in Burkina Faso.
Thermal and percolative transitions and the need for independent symmetry breakings in branched polymers on a Bethe lattice

We consider a very general model of equilibrium polymerization of branched polymers. Our model contains, as a special case, the ‘‘a priori equal probability’’ model considered by Flory and Stockmayer. In this limit, the model exhibits only percolation transition. We solve our general model in the interior of a Bethe lattice. There are thermal as well as percolation transitions in the model. Each of the two transitions requires an independent spontaneous symmetry breaking; neither implies the other. Without spontaneous symmetry breaking, the transitions do not manifest themselves. Thermal transitions correspond to singularities in the equation of state. Percolation transitions, on the other hand, do not correspond to any singularity in the equation of state. We also discuss the failure of a topological identity, valid for any finite Cayley tree, in the interior of the Bethe lattice. We consider various different cases to show the usefulness of our model. In particular, we argue that one must distinguish be.
In Vivo Human Skin Dielectric Properties Characterization and Statistical Analysis at Frequencies From 1 to 30 GHz

Precise data acquisition and modeling of healthy dermal dielectric properties are critical for accurate skin anomaly detection studies. For this purpose, an extensive campaign of around 1000 measurements across a band of 1–30 GHz leads to the conclusion that each skin region of interest (ROI) provides unique dielectric properties. Therefore, a single-skin model would not suffice to represent the complete human body. The acquired dielectric data are predominantly from the skin layer; however, considering the sensing depth of the utilized coaxial cable, the subcutaneous layers do have a minor contribution toward the effective dielectric properties seen at the probe/skin interface. Palmar skin has the maximum mean absolute percentage deviation in dielectric properties (around 34%) with respect to hand dorsum skin. The remaining measured ROIs (anterior wrist and anterior forearm) generate 4% and 8% dielectric deviation, respectively. Furthermore, female dermal dielectric constant values are observed to be on an average 9% higher across all measured ROIs compared with respective male skin. Subsequent statistical analysis of the measured data leads to the conclusion of a significant dielectric constant dependence on gender. The skin type generates a moderate but insignificant correlation with conductivity values. A similar analysis of volunteer weight and age details determined a weak association with the measured data.
Safety of Laparoscopic Cholecystectomy for Acute Cholecystitis in the Elderly: A Multivariate Analysis of Risk Factors for Intra and Postoperative Complications

Background and Objectives: This study investigates the impact of age upon the safety and outcomes of laparoscopic cholecystectomy performed for acute cholecystitis, by a multivariate approach. Materials and Methods: A 2-year retrospective study was performed on 333 patients admitted for acute cholecystitis who underwent emergency cholecystectomy. The patients included in the study group were divided into four age subgroups: A ≤49 years; B: 50–64 years; C: 65–79 years; D ≥80 years. Results: Surgery after 72 h from onset (p = 0.007), severe forms, and higher American Society of Anesthesiologists Physical Status Classification and Charlson comorbidity index scores (p < 0.001) are well correlated with older age. Both cardiovascular and surgical related complications were significantly higher in patients over 50 years (p = 0.045), which also proved to be a turning point for increasing the rate of conversion and open surgery. However, the comparative incidence did not differ significantly between patients aged from 50–64 years, 65–79 years and over 80 years (6.03%, 9.09% and 5.8%, respectively). Laparoscopic cholecystectomy (LC) was the most frequently used surgical approach in the treatment of acute cholecystitis in all age groups, with better outcomes than open cholecystectomy in terms of decreased overall and postoperative hospital stay, reduced surgery related complications, and the incidence of acute cardiovascular events in the early postoperative period (p < 0.001). Conclusions: The degree of systemic inflammation was the main factor that influenced the adverse outcome of LC in the elderly. Among comorbidities, diabetes was associated with increased surgical and systemic postoperative morbidity, while stroke and chronic renal insufficiency were correlated with a high risk of cardiovascular complications. With adequate perioperative care, the elderly has much to gain from the benefits of a minimally invasive approach, which allows a decreased rate of postoperative complications and a reduced hospital stay.
Association of vitamin D receptor and CYP2R1 mRNA expression with pulmonary tuberculosis

Introduction: The vitamin D metabolic pathway has been shown to play a pivotal role in the pathogenesis of pulmonary tuberculosis (PTB), and vitamin D receptor (VDR) and CYP2R1 gene variation are known to affect vitamin D status. Hence, this study aimed to evaluate VDR and CYP2R1 mRNA expression in peripheral blood mononuclear cells (PBMCs) in PTB patients. Material and methods: We measured VDR and CYP2R1 mRNA levels in 75 PTB patients and 63 healthy controls by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). The associations of VDR and CYP2R1 mRNA levels with clinical characteristics and laboratory indexes of PTB patients were also examined in this study. Results: Compared to healthy controls, the VDR mRNA level was significantly higher, and the CYP2R1 mRNA level was significantly lower in PBMCs from PTB patients (p = 0.047, p = 0.008, respectively). The CYP2R1 mRNA level in PTB patients with drug-resistant, unilateral tuberculosis foci was significantly higher than that in PTB patients without these clinical characteristics (p = 0.005, p = 0.048, respectively). In addition, our results demonstrated that the VDR mRNA expression level was positively correlated with erythrocyte sedimentation rate (ESR) (p = 0.045), while the CYP2R1 mRNA level was negatively correlated with ESR in PTB patients (p = 0.020). Conclusions: Altered VDR and CYP2R1 mRNA expression levels among PTB patients suggest their involvement in this disease.
Effect of perchloroethylene (PCE) and hydraulic shock loads on a membrane‐aerated biofilm reactor (MABR) biodegrading PCE

BACKGROUND: A membrane-aerated biofilm reactor (MABR) has previously been used to provide both anaerobic and aerobic conditions for mineralisation of perchloroethylene (PCE). However, very little is known about the stability of this reactor under hydraulic and PCE shock loads. An MABR was therefore subjected to sudden hydraulic and PCE shock loads in order to investigate its stability under such conditions. RESULTS: After each shock, the reactor responded with an increase of chemical oxygen demand (COD) and volatile fatty acids (VFA)s, a breakthrough of PCE and its biodegradation intermediates in the effluent, and a decrease in methane production. Although some PCE biodegradation intermediates were found in the effluent during each shock loading, the MABR performance recovered without the accumulation of any particular PCE biodegradation intermediates during PCE shock loads. During the hydraulic shock loads, the MABR was unstable at hydraulic retention times (HRTs) of 6 h with PCE and its biodegradation intermediates detected in the effluent. However, these intermediates were degraded when the HRT was reset to 48 h. CONCLUSIONS: This study suggests that MABRs can withstand fluctuations in influent strength and flows which occur in wastewater treatment works. Copyright © 2009 Society of Chemical Industry
Exploring the Online Learning Self-efficacy of Teacher Education Students at the Laguna State Polytechnic University: Basis for Transition to Flexible Learning System

The global pandemic due to the emergence of COVID-19 impacted the education sector causing the dramatic shift from conventional to flexible learning. To sustain learning continuity, online learning modality rises as a promising instructional response to the pandemic. This study utilized correlational research to explore the factors influencing the online learning self-efficacy of the 387 (57%) teacher education students. It also described the online learning self-efficacy, online readiness, coping strategies, and familiarity and capability of students to educational technology tools. The content-validated and researcher-made instrument which established an excellent reliability index (0.96), was administered via Google forms. Multiple regression analysis was employed to determine the significant predictors of the students' online learning self-efficacy. The results revealed that online readiness, coping strategies, and familiarity and capability significantly explain the variation in the student's self-efficacy to learn online. The administration and the teachers may consider the students' computer skills, reflect on their readiness for online learning, and understand their coping mechanisms in the digital classroom. These factors could be sourced out in developing instructional materials to meet the diverse needs of the students.
Hybrid Connectionist Symbolic Model for Morphologic Recognition by Tactile Sensing

Morphology and texture detection, which are important components of tactile sensing, augment the response of human beings to external stimuli. Similarly, tactile sensing-based information acquisition systems in robots can help enhance the interactions of robots with the surroundings. The main drawback of morphology and texture sensing methods is their inability to explain and quantify sensing information, which makes it difficult to utilize prior knowledge and necessitates a new training process to fit the new task, even if the changes between the existing and new tasks are minuscule. Another drawback is its dependence on large datasets. To solve these problems, a hybrid connectionist symbolic model (HCSM) is proposed herein that combines historic symbolic knowledge and end-to-end neural networks. The symbolic model requires a smaller dataset and possesses an improved transferability of detection. Neural networks can be easily established and exhibit better fault tolerance for non-ideal samples. The HCSM model combines these advantages. Experiments with the tactile-based morphology and texture detection demonstrated that the new method can transfer the detection ability to fit new tasks without requiring additional retraining and has a 16% higher recognition precision than a convolutional neural network, LeNet, AlexNet, VGG16, and ResNet. The HCSM method with these features can broaden the range of applications of tactile sensing.
Risk Mitigating Versus Risk Shifting: Evidence from Banks Security Trading in Crises

We show that risk mitigating incentives dominate risk shifting incentives in fragile banks. Risk shifting could be particularly severe in banking since it is the most opaque industry and banks are one of the most leveraged corporations with very low skin in the game. To analyze this question, we exploit security trading by banks during financial crises, as banks can easily and quickly change their risk exposure within their security portfolio. However, in contrast with the risk shifting hypothesis, we find that less capitalized banks take relatively less risk after financial market stress shocks. We show this using the supervisory ISIN-bank-month level dataset from Italy with all securities for each bank. Our results are over and above capital regulation as we show lower reach-for-yield effects by less capitalized banks within government bonds (with zero risk weights) or within securities with the same rating and maturity in the same month (which determines regulatory capital). Effects are robust to controlling for the covariance with the existence portfolio, and less capitalized banks, if anything, reduce concentration risk. Further, effects are stronger when uncertainty is higher, despite that risk shifting motives may be then higher. Moreover, three separate tests – based on different accounting portfolios (trading book versus held to maturity), the distribution of capital and franchise value – suggest that bank own incentives, instead of supervision, are the main drivers. Results are confirmed if we consider other sources of balance sheet fragility and different measures of risk-taking. Finally, evidence from the recent COVID-19 shock corroborates findings from the Global Financial Crisis and the Euro Area Sovereign Crisis.
Sulphur dioxide emissions in Europe 1880–1991 and their effect on sulphur concentrations and depositions

A historical emission inventory for sulphur dioxide has been compiled for Europe covering the period 1880–1991. The estimated emissions have been used as input to the sulphur module of the EMEP/MSC-W acid deposition model. The aim was to show the way and the extent to which the historical development of anthropogenic sulphur dioxide emissions alone has affected the concentration and deposition fields of oxidised sulphur in Europe. Although acknowledged, effects exerted by the meteorological variability and the changing oxidising capacity of the atmosphere over the years have not been taken into consideration. Long-term emission estimates reveal that combustion of coal was the dominant emission source before World War II in all countries and combustion of liquid fuels thereafter in most. Releases from industrial processes were relatively small. National sulphur dioxide emissions peaked mainly in the 1960s and 1970s, whilst emission control measures resulted in gradual reductions in most countries in the 1980s. In Europe as a whole, coal combustion remained the major emission source throughout the century. Total anthropogenic releases increased by a factor of 10 between the 1880 s and 1970s when they peaked at approximately 55 million tonnes of sulphur dioxide, followed by a 30% decline in the 1980s. Uncertainties in national emission estimates due to uncertain sulphur contents in fossil fuels are within ± 30% for 22 out of 28 countries and ± 45% for the rest. The location of emission sources in Europe has shown over the years a progressive detachment from the coalfields towards a widespread distribution, accompanied in the last decades by considerable emission reductions over north-western and parts of central Europe and substantial increases in the south and south-east. Modelled air concentrations and depositions reflect to a great extent the emission pattern, revealing two- to six-fold increases between the 1880 s and 1970s. Maximum sulphur loadings are confined over parts of north-western and central Europe. Accumulated depositions over the period 1880–1991 in these areas reach 600 g (S) m −2 . Emissions are principally in the form of sulphur dioxide, so that comparable concentrations of particulate sulphate in low emission regions indicate the importance of long range transport. Assuming a constant ecosystem sensitivity throughout the period, depositions sufficient to cause ecosystem damage may have occurred before 1880 in many areas of north-western and central Europe. Nevertheless, in large parts of eastern and southern Europe depositions are still below these critical loads. DOI: 10.1034/j.1600-0889.1996. t01-2-00005.x
Study on Characterization of the Degradation Products and Dynamics of Valtrate in the Artificial Gastrointestinal Fluid by HPLC- ESI MS/MSn

The present study developed a systematic method for the degradation products and dynamics of valtrate in artificial intestinal fluid and gastric fluid. HPLC-electrospray tandem mass spectrometry (HPLC-ESI-MSn) was applied to separate the degradation products of valtrate and identify structures of the main degradation products. Samples were separated on an Agilent Extend-Cl8 by gradient elution using acetonitrile and water–acetic acid (0.25%, v/v). Analysis was performed in positive ion mode with 3000 V of capillary voltage, 40 psi of atomization pressure, 10 L min−1 dry nitrogen gas velocity, and m/z 100–1000 of scan range. Six degradation products were all identified to own the stem-nucleus structures of baldrinals. Two of them were identified through the reference substances. An HPLC method with isocratic elution using acetonitrile and water (68:32, v/v) at 254 nm was established to determine content change of valtrate in artificial intestinal fluid and gastric fluid at different time points. The method was validated with good linearity in wide linear ranges (r2 = 0.9999), and good intra-day precision (RSD = 1.0%). The degradations of valtrate in artificial intestinal fluid and gastric fluid follow pseudo-first-order kinetic process, the half-life period in artificial gastric fluid is 1.73 hr, and in artificial intestinal fluid it is 1.61 hr. This study enriched the knowledge on degradation products of valtrate and may reveal the mechanism of the degradation of valtrate.
Influence of the Built-in Voltage on the Fill Factor of Dye-Sensitized Solar Cells

Dye-sensitized solar cells with different front contact materials to the nanoporous TiO2 layer are used to investigate the influence of the front contact barrier on the photovoltaic performance. The study uses devices that have SnO2:F, ZnO:Al, Al, or Au contacts underneath an amorphous TiO2 blocking layer and the nanocrystalline TiO2. These devices are illuminated via the semitransparent platinum back contact. Variations of the front contact have no significant influence on the open circuit voltage of the devices. In contrast, the fill factors of the solar cells exhibit systematic differences. The experimental current/voltage curves are fitted to a simple model that uses two diodes, one corresponding to the front contact/TiO2 interface and a second one for the TiO2/electrolyte interface.
Complexity Reduction and Control Techniques for Power-Constrained Video Coding

The ever-increasing demand for multimedia content imposes a big challenge for video compression. Today, smartphones are widely popular and in use. The high-quality cameras and high-resolution screens on these devices have elevated the user expectations for a higher resolution and higher quality video content. As a result, more High Definition (HD) and Ultra High Definition (UHD) content are being shared by users. The High Efficiency Video Coding (HEVC/H.265) was introduced as the latest video coding standard by ITU and MPEG, to cope with the high bitrate of this large content. It can provide almost twice the coding efficiency, compared to its predecessor, H.264/AVC. However, the encoding process for this standard includes algorithms with a higher computational complexity, due to the newly introduced coding tools, and a higher precision for the existing tools. As a consequence, HEVC encoding is power demanding, and thus hard to employ especially on battery-powered devices. Furthermore, many applications e.g. video streaming, cloud gaming, and power-constraint video coding, are sensitive to the coding delay (or power), and their tolerable delay (or processing power) varies through time. For this reason, not only reducing the complexity of video encoding is important, but a power-adaptive mechanism is crucial to enable the encoding within the defined power/delay quota. To address these issues, this thesis investigates the complexity of HEVC encoding and presents novel complexity reduction and complexity control algorithms for HEVC encoding. These contributions can be categorized in three main parts. The first contribution of this thesis considers the high complexity and power consumption of motion estimation in HEVC. Specifically, the baseline encoding algorithm is analyzed from a memory access point of view, which contributes heavily to the total power consumption of video encoding. A simple yet effective approach is presented that replaces the first step of the search for finding the best starting point, and also adaptively reduces the search range. This method reduces the memory access and encoding time, with negligible loss of coding efficiency.