bluuebunny/crossref_metadata_2025 huggingface dataset:
An Overview on the Production of Biodiesel Enabled by Continuous Flow Methodologies
Authors: Carlucci Claudia
Published: June 2022

Biodiesel was produced via transesterification reaction catalyzed by acids, bases, enzymes or supercritical fluids. The catalysis was homogeneous or heterogeneous and the process could be carried out in batch or using a continuous flow process. Microreactors allowed us to obtain better control of the experimental variables, such as temperature, pressure and flow rate, carrying out the reactions in safe conditions, avoiding exothermic and dangerous processes. The synthetic methodologies in continuous flow, combined with other technologies as microwave irradiation or ultrasounds, led to complete automation of the process with an increase in efficiency, also applicable on an industrial scale.
Application of Biotransformation-Guided Purification in Chinese Medicine: An Example to Produce Butin from Licorice
Authors: Wu Jiumn-Yih , Ding Hsiou-Yu , Wang Tzi-Yuan , Cai Cheng-Zhi , Chang Te-Sheng
Published: June 2022

Natural compounds are considered treasures in biotechnology; however, in the past, the process of discovering bioactive compounds is time consuming, and the purification and validation of the biofunctions and biochemistry of compounds isolated from a medicinal herb are tedious tasks. In this study, we developed an economical process called biotransformation-guided purification (BGP), which we applied to analyze licorice, a traditional Chinese medicine widely used in many therapies. This medicinal herb contains various flavonoids and triterpenoids and, thus, is a suitable material used to assess the ability of BGP to identify and produce bioactive compounds. In the BGP process, the ethyl acetate extract of a commercial licorice medicine was partially purified into three fractions by Sephadex LH-20 chromatography, and Bacillus megaterium tyrosinase (BmTYR) was used to catalyze the biotransformation of the extract from each fraction. One of the products produced via BmTYR-driven biotransformation was purified from the biotransformation-positive extract using preparative C-18 high-performance liquid chromatography, and it was identified as butin (3′-hydroxyliquiritigenin) through nucleic magnetic resonance and mass spectral analyses. Butin was produced from liquiritigenin through BmTYR-catalyzed hydroxylation, with commercial liquiritigenin as the biotransformation precursor. The proposed alternative approach quickly identified and isolated the biotransformed butin from licorice. Moreover, butin demonstrated an antioxidant activity that is stronger by over 100-fold compared with that of its precursor (liquiritigenin). This study showed that the economical BGP process could quickly obtain and validate bioactive molecules from crude extracts of medicinal herbs.
Application of Priming Strategy for Enhanced Paclitaxel Biosynthesis in Taxus × Media Hairy Root Cultures
Authors: Sykłowska-Baranek Katarzyna , Sygitowicz Grażyna , Maciejak-Jastrzębska Agata , Pietrosiuk Agnieszka , Szakiel Anna
Published: June 2022

Despite huge progress in biotechnological approaches to paclitaxel production, Taxus spp. in vitro culture productivity still remains a challenge. This could be solved by developing a new strategy engaging mechanisms of the primed defence response joined with subsequent elicitation treatment to circumvent limitations in paclitaxel biosynthesis. The hairy roots were primed by preincubation with β-aminobutyric acid (BABA) for 24 h or 1 week, and then elicited with methyl jasmonate (MeJA) or a mixture of MeJA, sodium nitroprusside and L-phenylalanine (MIX). The effect of priming was evaluated on a molecular level by examination of the expression profiles of the four genes involved in paclitaxel biosynthesis, i.e., TXS (taxadiene synthase), BAPT (baccatin III: 3-amino, 3-phenylpropanoyltransferase), DBTNBT (3′-N-debenzoyl-2-deoxytaxol-N-benzoyltransferase) and PAM (phenylalanine aminomutase), as well as rolC (cytokinin-β-glucosidase), originated from the T-DNA of Agrobacterium rhizogenes. The maximum paclitaxel yield was achieved in cultures primed with BABA for 1 week and elicited with MIX (3179.9 ± 212 µg/g dry weight), which corresponded to the highest expression levels of TXS and BAPT genes. Although BABA itself induced the investigated gene expression over control level, it was not translated into paclitaxel production. Nevertheless, preincubation with BABA essentially affected paclitaxel yield, and the duration of BABA pretreatment seemed to have the most pronounced impact on its productivity.
3-Thienylboronic Acid as a Receptor for Diol-Containing Compounds: A Study by Isothermal Titration Calorimetry
Authors: Efremenko Yulia , Mirsky Vladimir M.
Published: June 2022

The electrochemical activity of 3-thienylboronic acid and its feature to form polymer films makes it a perspective receptor material for sensor applications. The affinity properties of this compound were studied here by isothermal titration calorimetry. A number of different analytes were tested, and the highest binding enthalpy was observed for sorbitol and fructose. An increase of pH in the range of 5.5–10.6 results in the rise of the binding enthalpy with an increase of the binding constant to ~8400 L/mol for sorbitol or ~3400 L/mol for fructose. The dependence of the binding constant on pH has an inflection point at pH 7.6 with a slope that is a ten-fold binding constant per one pH unit. The binding properties of 3-thienylboronic acid were evaluated to be very close to that of the phenylboronic acid, but the electrochemical activity of 3-thienylboronic acid provides a possibility of external electrical control: dependence of the affinity of 3-thienylboronic acid on its redox state defined by the presence of ferro/ferricyanide in different ratios was demonstrated. The results show that 3-thienylboronic acid can be applied in smart chemical sensors with electrochemically controllable receptor affinity.
Efficacy of a Tibia Counter Rotator System for the Treatment of Internal Tibial Torsion in Children
Authors: Kim Sungmi , Suzuki Mitsuyoshi , Minowa Kei , Nittono Hiroshi , Shimizu Toshiaki
Published: June 2022

Internal tibial torsion is more common in the Asian population than in Western populations. Generally, surgery should be considered for the treatment of severe internal tibial torsion. As an alternative approach, the usefulness of a tibia counter rotator (TCR), a corrective orthosis based on the theory of the tibia torsional transformer, has been demonstrated, but the evidence is limited. In the present study, the efficacy and safety of TCR treatment were investigated in pediatric patients with internal tibial torsion. The subjects were 124 pediatric patients with internal tibial torsion who were between 3 and 15 years of age and had no underlying diseases. The severity of tibial intorsion was evaluated by the tibial transmalleolar angle (TMA). A TMA less than 5° was defined as internal tibial torsion, and less than −20° was defined as severe in this study. The median duration of TCR use was 11 (9, 12) (median (IQR: interquartile range)) months, and the treatment completion rate was 94.4% (117/124). The TMA at 12 months from the start of treatment in patients who completed treatment was 5° (0°, 10°) on the right (n = 66) (p < 0.01 vs. pretreatment) and 0° (−5°, 8°) on the left (n = 71) (p < 0.01 vs. pretreatment). The tibial torsional transformer used in this study is effective in the initial treatment of mild to severe internal tibial torsion, with no adverse effects. Although internal tibial torsion is generally expected to resolve spontaneously, TCR treatment may be an effective alternative to surgical therapy in the Asian pediatric population.
The Role of Arthroereisis in Improving Sports Performance, Foot Aesthetics and Quality of Life in Children and Adolescents with Flexible Flatfoot
Authors: Herdea Alexandru , Neculai Adrian-Gabriel , Ulici Alexandru
Published: June 2022

Flexible flatfoot represents one of the most common deformities of the lower limb, affecting children and adolescents. Aesthetic aspect, abnormal gait, pain and fatigue are by far the most important symptoms which determine parents to bring their children to the orthopedist. We set out to conduct a prospective study, case-controlled, including patients with symptomatic flexible flatfeet operated on by arthroereisis surgery and comparing them to a normal feet group of children age- and sex-matched (control group). Minimum follow-up time was 2 years. In total, 33 patients with bilateral arthroereisis were included and 36 patients formed the control group (12.12 +/− 1.85 years vs. 11.81 ± 2.40 years, p = 0.54). Quality of life improved postoperatively (p = 0.18) and was not different from the control group. Median running time improved postoperatively by 2.25 s (p < 0.0001) and got closer to the median running time from the control group (22.30 s compared to 20.94 s, p = 0.01). All radiological angles improved (p < 0.0001), but quality of life improvement was correlated with talonavicular coverage angle and Meary angle measurements. Flatfoot in children and adolescents may be a condition in which the quality of life and sports performance are decreased, compared to healthy children. Arthroereisis is a minimally invasive surgical procedure with a short recovery time and a short period before resumption of sport activities, which can be useful in certain types of flexible flatfoot due to its effectiveness on symptom reduction.
Screening of Diabetic Retinopathy Using Teleophthalmology to Complement Human Resources for Eye Health: A Systematic Review and Meta-Analysis
Authors: Zikhali Thembile , Kalinda Chester , Xulu-Kasaba Zamadonda Nokuthula
Published: June 2022

Diabetic retinopathy is a vascular disease of the retina that affects patients with uncontrolled diabetes. Untreated diabetic retinopathy (DR) can eventually lead to blindness. To date, diabetic retinopathy is the third leading cause of vision loss in the working class globally. Frequent retinal screening for all diabetic people is an effective method of preventing diabetic retinopathy blindness. This has relied on the use of ophthalmologists, but due to scarce resources, such as a shortage of human resources for eye health, this has denied many patients quality eye health care in a resource-limited setting. The recent advances on the use of teleophthalmology are promising to close this gap. This study aimed to map available evidence on the use of teleophthalmology in the screening of DR globally and to explore how this can be used to complement short-staffed eye clinics, especially in resource-constrained contexts. Studies were sourced from Google Scholar, PubMed, Science Direct, and EBSCO host. The final study selection was presented using a PRISMA chart. The mixed method appraisal tool was used to assess the quality of the nine studies included. The random effect model was used to estimate pooled prevalence estimates. Levels of heterogeneity were evaluated using Cochran’s Q statistic and I2. Of nine included studies, eight were from high-income countries. The screening was performed at the primary healthcare level in eight of nine included studies. Only one study used a mydriatic agent, and the commonly used fundus camera was the non-mydriatic fundus camera. The overall estimated pooled prevalence of DR was 29 (95%CI: 10–34). Teleophthalmology at the primary health care level showed that early intervention in diabetic retinopathy reduced avoidable blindness and ensured remote access to eye health professionals, thus alleviating the burden on them.
A Novel Sub-Pixel-Shift-Based High-Resolution X-ray Flat Panel Detector
Authors: Liu Jiayin , Kim Jae Ho
Published: June 2022

In this paper, we describe a novel sub-pixel shift (SPS)-based X-ray flat panel detector (FPD), which can achieve high resolution while maintaining a high SNR (signal-to-noise ratio). In the proposed architecture, an XY precision shift stage is applied to complete the sub-pixel shift process. In addition, image acquisition and high-resolution image composition are integrated in the FPD hardware. According to the relevant standards for detector image quality evaluation, we tested and evaluated some image quality indicators. The results show that the proposed FPD with SPS outperforms the original FPD without SPS technology. More specifically, the measured pixel size of the proposed FPD was reduced from 162 to 140 μm for 2 × 2 sub-pixel shift mode, and 132 μm for 4 × 4 sub-pixel shift mode, that is, the basic spatial detector resolution was improved by 13.6% for the simplest 2 × 2 sub-pixel shift mode, and by 18.5% for 4 × 4 sub-pixel shift mode. With this method, a lower-price FPD is elevated both in resolution and  SNRn to meet imaging quality requirements.
Effects of Sodium Carbonate and Calcium Oxide on Roasting Denitrification of Recycled Aluminum Dross with High Nitrogen Content
Authors: Ni Hongjun , Lu Chunyu , Zhang Yu , Wang Xingxing , Zhu Yu , Lv Shuaishuai , Zhang Jiaqiao
Published: June 2022

Aluminum dross is solid waste produced by the aluminum industry. It has certain toxicity and needs to be treated innocuously. The effect of sodium carbonate and calcium oxide on the denitrification efficiency of high nitrogen aluminum dross roasting was studied in this paper. By means of XRD, SEM and other characterization methods, the optimum technological parameters for calcination denitrification of the two additives were explored. The test results show that both additives can effectively improve the efficiency of aluminum dross roasting denitrification, and the effect of sodium carbonate is better. When the mass ratio of sodium carbonate to aluminum dross is 0.6, the roasting temperature is 1000 °C and the roasting time is 4 h, the denitrification rate can reach 91.32%.
Monitoring of Temperature Measurements for Different Flow Regimes in Water and Galinstan with Long Short-Term Memory Networks and Transfer Learning of Sensors
Authors: Pantopoulou Stella , Ankel Victoria , Weathered Matthew T. , Lisowski Darius D. , Cilliers Anthonie , Tsoukalas Lefteri H. , Heifetz Alexander
Published: June 2022

Temperature sensing is one of the most common measurements of a nuclear reactor monitoring system. The coolant fluid flow in a reactor core depends on the reactor power state. We investigated the monitoring and estimation of the thermocouple time series using machine learning for a range of flow regimes. Measurement data were obtained, in two separate experiments, in a flow loop filled with water and with liquid metal Galinstan. We developed long short-term memory (LSTM) recurrent neural networks (RNNs) for sensor predictions by training on the sensor’s own prior history, and transfer learning LSTM (TL-LSTM) by training on a correlated sensor’s prior history. Sensor cross-correlations were identified by calculating the Pearson correlation coefficient of the time series. The accuracy of LSTM and TL-LSTM predictions of temperature was studied as a function of Reynolds number (Re). The root-mean-square error (RMSE) for the test segment of time series of each sensor was shown to linearly increase with Re for both water and Galinstan fluids. Using linear correlations, we estimated the range of values of Re for which RMSE is smaller than the thermocouple measurement uncertainty. For both water and Galinstan fluids, we showed that both LSTM and TL-LSTM provide reliable estimations of temperature for typical flow regimes in a nuclear reactor. The LSTM runtime was shown to be substantially smaller than the data acquisition rate, which allows for performing estimation and validation of sensor measurements in real time.
Wettability and Spreading Behavior of Sn–Ti Alloys on Si3N4
Authors: Wang Huaijin , Fu Wei , Xue Yidi , Huo Shihui , Guo Min , Hu Shengpeng , Song Xiaoguo
Published: June 2022

The purpose of this study was to investigate the wetting behavior and interfacial reactions of Sn-Ti alloys, which has been widely applied to join ceramics with metals, on Si3N4 substrates. The isothermal wetting process of Sn-xTi alloys (x = 0.5, 1.0, 1.5, 2.0 and 2.5 wt.%) on Si3N4 was systematically studied from 1223 K to 1273 K through sessile drop methods. The microstructures of the interface were characterized by X-ray diffraction (XRD) and microscope (SEM). The active Ti element remarkably enhanced the wettability of Sn-xTi melts on Si3N4 substrates because of the formation of metallic reaction layers (Ti5Si3 and TiN). With the Ti content rising, thicker Ti5Si3 layer formed on the TiN phase inducing a lower equilibrium contact angle. The value of the lowest contact angle was 6°, which was obtained in the Sn-2.0Ti/Si3N4 system at 1273 K. Larger Ti5Si3 grains were found in Sn-2.5Ti melt and a higher final contact angle was obtained. Lower temperature increased the final contact angle and slowed down the spreading rate. The formation of reaction products was calculated thematically, and the spreading kinetics was calculated according to the reaction-driven theory. The spreading behavior of Sn-Ti alloy on Si3N4 ceramic was composed of rapid-spreading stage and sluggish-spreading stage. The calculated activity energy of spreading was 395 kJ/mol. Eventually, the wetting process of Sn-2.0Ti/Si3N4 system was successfully elucidated. These results provide significant guidance information for the brazing between metals and Si3N4 ceramic.
Effect of Chlorine Addition on Texture and Superconducting Performance of YBa2Cu3O7−δ-Coated Conductors
Authors: Chen Mingyue , Liu Zhiyong , Li Minjuan , Yan Zhichao , Huang Rongtie , Qian Sida , Chen Jing , Cai Chuanbing
Published: June 2022

YBa2Cu3O7−δ (YBCO) thin films with the addition of Cl were prepared on Hastelloy tape by the extremely low fluorine metal-organic deposition (MOD) technique. The composition and microstructure of the present samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was revealed that the Cl-added YBCO thin films achieved better texture and density compared with the pure YBCO films. The superconducting properties at magnetic fields were measured using the magnetic property measurement system (MPMS). The results showed that the sample onset transition temperature (Tc, on) did not change significantly after the addition of Cl. The critical current density (Jc) in the presence of YBCO with the addition of Cl increased significantly. Meanwhile, both the Jc and gravitational force (Fp) of the (Cl, Hf) co-added YBCO films were further enhanced at different magnetic fields. The thermodynamic analysis of the BaCO3 removal reaction revealed that the addition of Cl to YBCO formed chlorine compounds, which were effective in avoiding the formation of BaCO3. Further, the calculation results of the Gibbs free energy at different pressure quotients showed that the stability of the relevant chlorine compounds occurred in the order of BaCl2 > CuCl2 > YCl3 and the oxidation of BaCl2 to BaO required a higher temperature compared to BaF2, implying the potential advantages of inhibiting the a-axis growth.
Comparing Genetic and Field-Based Estimates of Population Connectivity in Marbled Salamanders, Ambystoma opacum
Authors: Posbic-Leydet Karine E. , Glennon Kelsey L. , Fisher Jolene T. , Church Don R. , Church Sheri A.
Published: June 2022

Estimating connectivity is key for maintaining population viability for pond-breeding amphibians, especially in areas where habitat alterations occur. Here, we used genetic data (microsatellites) to estimate connectivity of marbled salamanders, Ambystoma opacum, among three focal ponds and compared it to field data (capture-mark-recapture estimates) of movement among the same ponds. In addition, we derived least-cost dispersal paths from genetic data and compared them to field connectivity estimates. We found that genetic and field estimates of dispersal were generally congruent, but field-based paths were more complex than genetic-based paths. While both methods complement each other in identifying important source-sink metapopulation dynamics to inform efficient conservation management plans, field data provide a more biologically accurate understanding of the spatial movement of individual marbled salamanders.
Individual and Co-Expression Patterns of FAM83H and SCRIB at Diagnosis Are Associated with the Survival of Colorectal Carcinoma Patients
Authors: Jeong Tae Young , Lee Hae In , Park Min Su , Seo Min Young , Jang Kyu Yun
Published: June 2022

Background: FAM83H is important in teeth development; however, an increasing number of reports have indicated a role for it in human cancers. FAM83H is involved in cancer progression in association with various oncogenic molecules, including SCRIB. In the analysis of the public database, there was a significant association between FAM83H and SCRIB in colorectal carcinomas. However, studies evaluating the association of FAM83H and SCRIB in colorectal carcinoma have been limited. Methods: The clinicopathological significance of the immunohistochemical expression of FAM83H and SCRIB was evaluated in 222 colorectal carcinomas. Results: The expressions of FAM83H and SCRIB were significantly associated in colorectal carcinoma tissue. In univariate analysis, the nuclear expressions of FAM83H and SCRIB and the cytoplasmic expression of SCRIB were significantly associated with shorter survival of colorectal carcinomas. The nuclear expressions of FAM83H and SCRIB and the cytoplasmic expression of SCRIB were independent indicators of shorter cancer-specific survival in multivariate analysis. A co-expression pattern of nuclear FAM83H and cytoplasmic SCRIB predicted shorter cancer-specific survival (p < 0.001) and relapse-free survival (p = 0.032) in multivariate analysis. Conclusions: This study suggests that FAM83H and SCRIB might be used as prognostic markers of colorectal carcinomas and as potential therapeutic targets for colorectal carcinomas.
TOX Expression in Mycosis Fungoides and Sezary Syndrome
Authors: Pileri Alessandro , Cavicchi Martina , Bertuzzi Clara , Righi Simona , Zengarini Corrado , Sabattini Elena , Roncador Giovanna , Agostinelli Claudio
Published: June 2022

Mycosis fungoides (MF) and Sezary syndrome (SS) are the two most common type of cutaneous T-cell lymphoma (CTCL). Currently, no markers can be clearly related to prognosis or to differential diagnosis between early stages and inflammatory benign diseases (IBD). The thymocyte selection-associated high mobility group box factor (TOX), has been proposed as a possible marker in differential diagnosis between early CTCL stages and IBD. Recently TOX has been related to prognosis. We aimed to investigate whether TOX may be a diagnostic or prognostic marker. MF and SS biopsies between 2010 and 2020 were retrieved. New tissues slides were stained with an anti-TOX antibody, (Clone NAN448B). On each slide, 5 fields were examined at high magnification (400×), to evaluate the percentage of marker-positivity in a quantitative way. Thirty-six patients (12 females and 24 males) and 48 biopsies were collected. Nine patients had multiple biopsies. TOX expression in MF/SS cases showed an increase from early to advanced phases. TOX was not regarded as a prognostic marker due to the absence of significant changes by comparing early MF cases with reactive conditions. TOX statistical significance increased in patients alive with disease and in those dead of disease (p = 0.013 and = 0.0005, respectively) as compared with patients in complete remission. Our results show that TOX should be regarded more as a prognostic than a diagnostic marker.
Hepatocellular Carcinoma Presenting Simultaneously with Echinococcal Cyst Mimicking a Single Liver Lesion in a Non-Cirrhotic Patient: A Case Report and Review of the Literature
Authors: Kovač Jelena Djokić , Mitrović Milica , Janković Aleksandra , Andrejević Marko , Bogdanović Aleksandar , Zdujić Predrag , Đinđić Uroš , Dugalić Vladimir
Published: June 2022

A coexistance of liver cystic echinococcosis (CE) and hepatocellular carcinoma (HCC) is very rare. HCC is the leading cause of cancer-related mortality worldwide, while CE is a globally endemic zoonosis caused by the cestode tapeworm Echinococcus granulosus. The association between these two diseases is still not well-defined. A preoperative diagnosis may be challenging, especially if HCC and CE present as a single lesion and if atypical imaging features are present. Herein, we present a case of the patient that was initially diagnosed as an extensive necrotic tumor in the left liver lobe and highly suspicious of being HCC associated with peritumoral hematoma. Left hemihepatectomy was performed, and the histopathological findings showed the collision of two lesions: a hydatid cyst and HCC.
The Red Seaweed Giant Gelidium (Gelidium corneum) for New Bio-Based Materials in a Circular Economy Framework
Authors: Mouga Teresa , Fernandes Isabel Barreto
Published: June 2022

Gelidium corneum (Giant Gelidium or Atlantic agar) is a well-known red seaweed harvested for its high-quality agar content. Agar is a mixture of the polysaccharides used in the food industry as a gelling, thickener, clarifying, and stabilizer agent. The best agar quality is also used in the laboratory as bacteriological agar. Yet, in recent years, the species has been studied for many other applications. Examples of uses are pharmaceuticals, cosmetics, food supplements, bioremediation, biofuels, biofertilizers and biostimulants, biomaterials, and nanocrystals, among others. The use of this biomass, though, raises concerns about the sustainability of the resource, since this is not a cultivated species, being harvested in the wild. Thus, other uses of G. corneum biomass increase pressure on wild stocks already stressed due to climate change. However, in a biorefinery approach, a new trend is emerging, using waste biomass rather than harvested biomass to produce new bio-based materials. These are smart solutions that transform waste into innovative products, useful for various sectors of society while reducing the impact of biomass exploitation. The aim of this review paper, thus, is to address the current state of G. corneum biology, ecology, threats, its current uses and market, and the ongoing research on innovative proposals in a circular economy framework.
“Thank You for Your Sacrifice, I Will Try to Make Sure Your Donation Wasn’t in Vain”: Undergraduate Science Students’ Perceptions on the Use of Cadaveric Material in Learning Anatomy
Authors: Flack Natasha AMS , Frost Katie , Aravazhi Shanmugapriya , Macmillan Athena , Blyth Phil , Woodley Stephanie J. , Nicholson Helen D. , Hurren Bradley J. , Bird Rebecca J.
Published: June 2022

Human-cadaveric material is a valuable resource for teaching anatomy, and a lot of research engaging medical students shows they benefit, in a variety of ways, from engaging with this material. However, more and more students who study anatomy are non-medical. Thus, they may have different educational foci than that of medical students, and, therefore, different perspectives on the value of human-cadaveric material as a learning resource. The aim of this study was to explore the perceptions of science students studying anatomy, in the use of learning using cadaveric material. Two cohorts of undergraduate science students studying anatomy (second-year, third-year) completed two surveys; one at the start and another following the completion of their semester-long courses that utilised prosections (second-year) and dissection (third-year) as a primary way of learning anatomy. Likert-scale and open-ended responses were analysed using a general inductive approach, and common emergent themes were identified. In total, 134 second-year and 77 third-year students completed the first survey, and 80 second-year and 36 third-year students completed the second survey. For the majority of students, their interactions with human material were positive and most of them cope well. Students acknowledged the opportunity and expressed gratitude for an invaluable learning resource. If at first the situation is confronting, with more experience, exposure, and staff support, most students find their initial concerns dissipate. This study identifies key areas of the learning journey that work well and others that can be improved, to better prepare students for learning with human material.
ROENet: A ResNet-Based Output Ensemble for Malaria Parasite Classification
Authors: Zhu Ziquan , Wang Shuihua , Zhang Yudong
Published: June 2022

(1) Background: People may be infected with an insect-borne disease (malaria) through the blood input of malaria-infected people or the bite of Anopheles mosquitoes. Doctors need a lot of time and energy to diagnose malaria, and sometimes the results are not ideal. Many researchers use CNN to classify malaria images. However, we believe that the classification performance of malaria parasites can be improved. (2) Methods: In this paper, we propose a novel method (ROENet) to automatically classify malaria parasite on the blood smear. The backbone of ROENet is the pre-trained ResNet-18. We use randomized neural networks (RNNs) as the classifier in our proposed model. Three RNNs are used in ROENet, which are random vector functional link (RVFL), Schmidt neural network (SNN), and extreme learning machine (ELM). To improve the performance of ROENet, the results of ROENet are the ensemble outputs from three RNNs. (3) Results: We evaluate the proposed ROENet by five-fold cross-validation. The specificity, F1 score, sensitivity, and accuracy are 96.68 ± 3.81%, 95.69 ± 2.65%, 94.79 ± 3.71%, and 95.73 ± 2.63%, respectively. (4) Conclusions: The proposed ROENet is compared with other state-of-the-art methods and provides the best results of these methods.
Research on Simulation Design of MOS Driver for Micro-LED
Authors: Zhang Xuesong , Yin Luqiao , Ren Kailin , Zhang Jianhua
Published: June 2022

Micro-LED is a new technology applied in the display field, which has the advantages of self-illumination, low power consumption, high brightness, long life and ultra-high resolution, and has broad application prospects. Using MOS devices to drive micro-LED can enable each unit to have its own drive, thus improving the yield and reducing the subsequent repair processes. In this paper, Sentaurus TCAD simulation software is used to design and simulate NMOS/PMOS devices and their driving circuits. For the first time, CMOS inverters are used to directly drive Micro-LED. Three kinds of driving circuits are compared and analyzed according to their simulation results in output characteristics and transient characteristics. In terms of switching characteristics caused by output characteristics, a CMOS inverter driving a micro-LED circuit has no problems of incomplete turn-off and has greater advantages. In the switching characteristics aspect caused by transient characteristics, PMOS driving a micro-LED circuit has the shortest turn-on time and greater advantages. When compared with a micro-LED driven by an access current-limiting resistor, a micro-LED driven by a direct drive has a smaller on-time value and greater advantages.
Evaluation of Black-Box Web Application Security Scanners in Detecting Injection Vulnerabilities
Authors: Althunayyan Muzun , Saxena Neetesh , Li Shancang , Gope Prosanta
Published: June 2022

With the Internet’s meteoric rise in popularity and usage over the years, there has been a significant increase in the number of web applications. Nearly all organisations use them for various purposes, such as e-commerce, e-banking, e-learning, and social networking. More importantly, web applications have become increasingly vulnerable to malicious attack. To find web vulnerabilities before an attacker, security experts use black-box web application vulnerability scanners to check for security vulnerabilities in web applications. Most studies have evaluated these black-box scanners against various vulnerable web applications. However, most tested applications are traditional (non-dynamic) and do not reflect current web. This study evaluates the detection accuracy of five black-box web application vulnerability scanners against one of the most modern and sophisticated insecure web applications, representing a real-life e-commerce. The tested vulnerabilities are injection vulnerabilities, in particular, structured query language (SQLi) injection, not only SQL (NoSQL), and server-side template injection (SSTI). We also tested the black-box scanners in four modes to identify their limitations. The findings show that the black-box scanners overlook most vulnerabilities in almost all modes and some scanners missed all the vulnerabilities.
A Unified FPGA Realization for Fractional-Order Integrator and Differentiator
Authors: Monir Mohamed S. , Sayed Wafaa S. , Madian Ahmed H. , Radwan Ahmed G. , Said Lobna A.
Published: June 2022

This paper proposes a generic FPGA realization of an IP core for fractional-order integration and differentiation based on the Grünwald–Letnikov approximation. All fractional-order dependent terms are approximated to simpler relations using curve fitting to enable an efficient hardware realization. Compared to previous works, the proposed design introduces enhancements in the fractional-order range covering both integration and differentiation. An error analysis between software and hardware results is presented for sine, triangle and sawtooth signals. The proposed generic design is realized on XC7A100T FPGA achieving frequency of 9.328 MHz and validated experimentally for a sine input signal on the oscilloscope. The proposed unified generic design is suitable for biomedical signal processing applications. In addition, it can be employed as a laboratory tool for fractional calculus education.
Comparative Study of PM10 Concentrations and Their Elemental Composition Using Two Different Techniques during Winter–Spring Field Observation in Polish Village
Authors: Mach Tomasz , Olszowski Tomasz , Rogula-Kozłowska Wioletta , Rybak Justyna , Bralewska Karolina , Rogula-Kopiec Patrycja , Bożym Marta , Majewski Grzegorz , Ziembik Zbigniew , Kuczuk Anna
Published: June 2022

The aims of this study were to determine the concentrations and elemental composition of PM10 in the village of Kotórz Mały (Poland), to analyse their seasonal variability, to determine the sources of pollutant emissions and to compare the consistency of the results obtained using different methods. Sampling and weather condition measurements were carried out in the winter (January–February) and spring (April) of 2019. Two combinations of different techniques were used to examine PM10 concentrations and their chemical composition: gravimetric method + atomic absorption spectrometry (GM+AAS) and continuous particle monitor + energy dispersive X-ray fluorescence (CPM+EDXRF). In winter, the average concentrations of PM10 measured by the GM and CPM were similar (GM 44.3 µg/m3; CPM 34.0 µg/m3), while in spring they were clearly different (GM 49.5 µg/m3; CPM 29.8 µg/m3). Both AAS and EDXRF proved that in both seasons, Ca, K and Fe had the highest shares in the PM10 mass. In the case of the lowest shares, the indications of the two methods were slightly different. Factor analysis indicated that air quality in the receptor was determined by soil erosion, coal and burning biomass, and the combustion of fuels in car engines; in the spring, air quality was also affected by gardening activities.
Concentrated Solar Power with Thermoelectric Generator—An Approach Using the Cross-Entropy Optimization Method
Authors: Ider João , Oliveira Adhimar , Rubinger Rero , Silva Ana Karoline , Assini Aluízio , Tiago-Filho Geraldo , Baldissera Marcia
Published: June 2022

In this research, a Concentrated Solar Power (CSP) as a Parabolic Trough Collector (PTC), using Peltier cooling modules for power generation was analyzed by the Cross-Entropy method. When comparing conventional solar electric generators with this system, we have the advantage that it is compact and lightweight and can be easily assembled and used as low-cost power generation equipment. For this system, we perform I(V) measurements and use fit models to accurately extract the model parameters. This is all in a standalone, robust, and simultaneous fit of three equations, through the global optimization method called Cross-Entropy. This is a robust method that had never been applied to extract parameters in a thermoelectric generation.
Charcoal Production in Portugal: Operating Conditions and Performance of a Traditional Brick Kiln
Authors: Charvet Felix , Matos Arlindo , Figueiredo da Silva José , Tarelho Luís , Leite Mariana , Neves Daniel
Published: June 2022

Charcoal is produced in large quantities in the Portuguese region of Alentejo mainly using traditional brick kilns. Information about this type of carbonization technology is scarce, which makes it urgent to characterize the process as a starting point for performance improvements. In this context, this study aims to characterize the operation of a cylindrical brick kiln (≈80 m3) during regular wood carbonization cycles. Relevant process parameters were monitored along with the yields and/or composition of the main products (carbonization gas, charcoal, and charcoal fines) to evaluate the mass balance of the process. The results show that the bulk of the kiln operates at temperatures below 300 °C, which greatly limits the quality of the charcoal. For instance, the fixed carbon content of charcoal can easily be as low as 60 wt.%. The yield of charcoal is also low, with values below 25 wt.% of dry wood feed. This means that significant quantities of by-products are generated in the process with little or no commercial value. Modifications in the carbonization process are needed to improve efficiency, charcoal quality, and environmental acceptance to sustain this activity in regions where it still represents vital income related to wood-waste management.
Fracture Distribution Characteristics in Goaf and Prevention and Control of Spontaneous Combustion of Remained Coal under the Influence of Gob-Side Entry Retaining Roadway
Authors: Zhang Jianguo , Wang Wen , Li Yanhe , Li Huamin , Zhang Guangjie , Wu Yiheng
Published: June 2022

Based on the ventilation characteristics of the gob-side entry retaining face, a mathematical model of spontaneous combustion in the gob-side entry retaining face is established. From the overburden caving of the goaf along the goaf retaining roadway, the development characteristics of rock strata and residual coal fissures in the goaf are summarized and analyzed. In addition, by using numerical simulation software, the effects of normal mining period, goaf retaining roadway as return air roadway, air leakage prevention, and nitrogen injection measures in goaf on spontaneous combustion in goaf are studied, and the distribution characteristics of flow field, oxygen concentration field and temperature field in goaf are obtained. The results show that the mining of the Geng 20 working face has a significant impact on the Geng 19 coal seam. The Geng 19 coal seam is in the range of fracture zone, and the fracture is well developed. Furthermore, the permeability coefficient of the Geng 19 coal seam increases sharply, air leakage in the goaf is increased along the goaf retaining roadway, and the range of oxygen concentration is enlarged, which results in a temperature rise in the goaf. Therefore, air leakage measures are proposed along the goaf to inject 900 m3/h of nitrogen into the goaf, which can prevent the spontaneous combustion of coal left over in the goaf. In addition, according to the characteristics of fracture development and numerical simulation of spontaneous combustion in goaf under the goaf retaining roadway, the hierarchical prevention, control, and fire extinguishing technology system of the goaf retaining roadway is constructed.
Impacts of Urban Development on Regional Green Development Efficiency—A Case of the Yangtze River Delta in China
Authors: Li Dian , Shangguan Ziheng , Huang Malan , Zhang Xinyue , Tang Lu
Published: June 2022

Green development is a significant concept that cannot be ignored in contemporary society. However, in the context of China’s transition from high-speed growth to high-quality development, the complex impact of urban development has brought great challenges to the urban green environment. In this paper, the impact of urban development on green development efficiency (GDE) was studied. First and foremost, a Super-SBM model was introduced to measure the GDE of 41 cities in the Yangtze River Delta during 2009–2018. Moreover, a Tobit model was used to analyze the correlation between four urban development factors, including economic development and GDE. According to the results, the mean GDE of the Yangtze River Delta is 0.824, and the GDE in most cities there has shown a fluctuating growth trend in this decade. By comparison, the GDEs of coastal cities and cities in the southeast of the Yangtze River Delta were generally higher than those of cities in the north, indicating that the green development is geographically unbalanced, and there is spatial heterogeneity in the area studied. The study’s results also suggest that the urban economic development, innovation level, and government planning play a significant role in stimulating urban green development, and that the expansion of urban construction area hinders the improvement of GDE.
Renewable Energy Community Pairing Methodology Using Statistical Learning Applied to Georeferenced Energy Profiles
Authors: Lucas Alexandre , Carvalhosa Salvador
Published: June 2022

Renewable energy communities (REC) are bound to play a crucial role in the energy transition, as their role, activities, and legal forms become clearer, and their dissemination becomes larger. Even though their mass grid integration, is regarded with high expectations, their diffusion, however, has not been an easy task. Its legal form and success, entail responsibilities, prospects, trust, and synergies to be explored between its members, whose collective dynamics should aim for optimal operation. In this regard, the pairing methodology of potential participants ahead of asset dimensioning seems to have been overlooked. This article presents a methodology for pairing consumers, based on their georeferenced load consumptions. A case study in an area of Porto (Asprela) was used to test the methodology. QGIS is used as a geo-representation tool and its PlanHeat plugin for district characterization support. A supervised statistical learning approach is used to identify the feature importance of an overall district energy consumption profile. With the main variables identified, the methodology applies standard K-means and Dynamic Time Warping clustering, from which, users from different clusters should be paired to explore PV as the main generation asset. To validate the assumption that this complementarity of load diagrams could decrease the total surplus of a typical PV generation, 18 pairings were tested. Results show that, even though it is not true that all pairings from different clusters lead to lower surplus, on average, this seems to be the trend. From the sample analyzed a maximum of 36% and an average of 12% less PV surplus generation is observed.
Possible Scenarios for Reduction of Carbon Dioxide Emissions in Serbia by Generating Electricity from Natural Gas
Authors: Klimenta Dardan , Mihajlović Marija , Ristić Ivan , Andriukaitis Darius
Published: June 2022

The main purpose of this paper is to develop possible scenarios for reducing carbon dioxide (CO2) emissions in Serbia by switching from coal-fired to natural gas-fired electricity generation by the end of 2050. Accordingly, the challenges are to establish scenarios and identify measures that are best suited to all Western Balkan countries. In particular, this paper proposes a number of energy mix scenarios that offer some options for reducing CO2 emissions while maintaining an economic way of consumption. Projections of these reduction scenarios are obtained by combining the Kaya identity with the emission factor method. A simplified methodology based on sensitivity analysis is used as a source of data to estimate the nonstatistical uncertainty limits for the projections of the reduction scenarios. The sensitivity analysis is carried out using historical data from Serbia for the period from 1990 to 2019. In addition, a direct verification of the proposed methodology is performed based on historical data for 2020. The developed scenarios 1 and 2 show that CO2 emissions could be reduced by 10.94% and up to 74.44% from baseline in 1990, respectively. The obtained results are also contrasted with the data available for some other countries with similar experiences. Finally, it is found that the developed scenarios are achievable only at significantly decreased levels of coal-fired electricity generation.
A Backcasting Analysis toward a 100% Renewable Energy Transition by 2040 for Off-Grid Islands
Authors: Supapo Khrisydel Rhea M. , Lozano Lorafe , Tabañag Ian Dominic F. , Querikiol Edward M.
Published: June 2022

The rapid increase in energy consumption results from population growth and technological advancement, while economic growth also relies heavily on the availability of energy. As fossil fuels become scarcer and greenhouse gas emissions increase, renewable energy sources are regarded as practical solutions to meet increasing energy demands. This study aims to develop a sustainable energy transition pathway for off-grid island communities in the Philippines. It adopts the concept of backcasting analysis, focusing on the demand and supply side of the energy transition. The transition considers three milestones: business as usual (BAU), minimal transition scenario (MTS), and absolute transition scenario (ATS). The techno-enviro-economic analysis is performed for each milestone to determine the optimal energy resource mix while addressing the three dimensions of the Energy Trilemma: energy security, energy equity, and environmental sustainability. The approach is implemented in three off-grid island municipalities in Palawan, Philippines: Araceli, Balabac, and Cuyo. The results suggest that the optimal electrification configuration for each island at the MTS is a hybrid system consisting of a diesel generator and solar photovoltaics with batteries, while at the ATS, it is a hybrid system of solar photovoltaics and wind with batteries. In addition, greenhouse gas emissions are reduced by 79.7% in Araceli, 78.7% in Balabac, and 41.2% in Cuyo from the BAU scenario to MTS. The actors involved in said transition are identified. A transitional pathway can be seen as a strategic plan to achieve the desired goal: to have a sustainable energy transition.
Enhanced Exoelectrogenic Activity of Cupriavidus metallidurans in Bioelectrochemical Systems through the Expression of a Constitutively Active Diguanylate Cyclase
Authors: Alviz-Gazitua Pablo , Espinoza-Tofalos Anna , Formicola Francesca , Guiliani Nicolas , Turner Raymond J. , Franzetti Andrea , Seeger Michael
Published: June 2022

Electroactive bacteria have a wide range of applications, including electricity production, bioremediation, and the sensing of toxic compounds. Bacterial biofilm formation is often mediated by the second messenger cyclic guanosine monophosphate (c-di-GMP) synthesized by a diguanylate cyclase (DGC). The role of c-di-GMP in the expression of c-type cytochromes has been previously reported. The aim of this study was to determine the bioelectrogenic activity of Cupriavidus metallidurans strain CH34 pJBpleD*, which possesses a constitutively active DGC that increases c-di-GMP levels. Notably, the heterologous expression of the constitutively active DGC in C. metallidurans strain CH34 pJBpleD* showed a higher biofilm formation and increased the electrical current production up to 560%. In addition, C. metallidurans CH34 pJBpleD* showed increased levels of c-type cytochrome-associated transcripts compared with the wild-type strain CH34. Scanning electron microscopies revealed a denser extracellular matrix with an increased exopolymeric substance content in the CH34 pJBpleD* biofilm on the electrode surface. The results of this study suggest that higher levels of c-di-GMP synthesized by a constitutively active diguanylate cyclase in C. metallidurans strain CH34 pJBpleD* activated the formation of an electroactive biofilm on the electrode, enhancing its exoelectrogenic activity.