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Environmental contamination with heavy metals is a threat to the organisms due to their toxicity, persistence and bioaccumulation in food chains. The study was aimed to assess cadmium (Cd) effect on calcium (Ca) level in bones of a freshwater fish Channa gachua. 42 fish individuals were kept into six (6) aquaria; labelled aq.0, 1, 2, 3,4 and 5 in the laboratory for treatment. Aq.0 was control group and aq.1, 2,3,4,5 were experimental with treatment solution of Cd 0, 0.1ppm, 0.5ppm, 1ppm, 2.5ppm and 5ppm respectively for three months. After exposure, bones tissue were examined for Cd accumulation and Ca concentration. Highest accumulation of Cd were recorded in aq.5 mean 46.86 ± 0.46 mgkg-1 .and lowest in the control group with mean 0.61 ± 0.06 mgkg-1. The order of Cd bioaccumulation in bones were aq.5 > aq.4 >aq.3 > aq.2 > aq.1 > aq.0. Highest concentration of Ca were noted in aq.0 (Control group) mean 7888.06 ± 4827.22 mgkg-1 and lowest were 1132.36 ± 203.73 mgkg-1 in aq.5 (at 5.0 ppm). Generally a pattern of decreasing Ca level were observed with each rise of Cd bioaccumulation aq.0 > aq.1 > aq.2 > aq.3 > aq.4 > aq.5. Current study indicated that Cd accumulation have substantial effect on Ca level in bones and hence on skeleton system. Strict rules must be implemented by government to control metals pollution and exploitations of biota. Resumo A contaminação ambiental com metais pesados é uma ameaça aos organismos devido à sua toxicidade, persistência e bioacumulação nas cadeias alimentares. O estudo teve como objetivo avaliar o efeito do Cd sobre o nível de Ca em ossos de peixes de água doce Channa gachua. Quarenta e dois indivíduos de peixes foram mantidos em seis aquários; marcado aq. 0, 1, 2, 3, 4 e 5 no laboratório para tratamento. Aq. 0 foi o grupo controle e aq. 1, 2, 3, 4, 5 foram experimentais com solução de tratamento de Cd 0, 0,1 ppm, 0,5 ppm, 1 ppm, 2,5 ppm e 5 ppm respectivamente por três meses. Após a exposição, o tecido ósseo foi examinado quanto ao acúmulo de Cd e concentração de Ca. O maior acúmulo de Cd foi registrado em aq. 5 com média de 46,86 ± 0,46 mgkg-1 e o menor no grupo controle com média de 0,61 ± 0,06 mgkg-1. A ordem de bioacumulação de Cd nos ossos foi aq. 5 > aq. 4 > aq. 3 > aq. 2 > aq. 1 > aq. 0. A concentração mais alta de Ca foi observada em aq. 0 (grupo controle) média de 7.888,06 ± 4.827,22 mgkg-1 e a mais baixa foi de 1.132,36 ± 203,73 mgkg-1 em aq. 5 (a 5,0 ppm). Geralmente um padrão de diminuição do nível de Ca foi observado com cada aumento da bioacumulação de Cd aq. 0 > aq. 1 > aq. 2 > aq. 3 > aq. 4 > aq. 5. O estudo atual indicou que o acúmulo de Cd tem efeito substancial no nível de Ca nos ossos e, portanto, no sistema esquelético. Regras estritas devem ser implementadas pelo governo para controlar a poluição por metais e a exploração da biota.

Three types of mills (Buhler, Quadrumat, and industry mill) have been used to determine the effect of mill type on the quality of the produced flour. Quadrumat and Buhler mills are usually used to produce flour at a laboratory level. Flour quality has been determined physically, chemically, and rheologically. Results showed that the particle size of flour produced by Buhler mill (FPB) was finer (mostly less than 132 μm) than other produced flour, while flour produced by Quadrumat mill (FPQ) had 8% particle size bigger than 50gg, which is more than Iraqi accepted limit (5%). The moisture content of FPQ exceeded the moisture content limit (14%). While, all flour produced by industry mills (FPI) was within the Iraqi standard in term of particle sizes and moisture content. Gluten content of FPB was higher than other produced flours; however, most increments were not significantly different. The results also showed that using different mills has no clear effect on the gluten index and alpha-amylase activity. Farinogram and extensogram results showed that FPQ was stronger than other produced flour followed by FPI. In conclusion, the quality of FPQ was closer to the quality of FPI, however, Quadrumat mill needs to be adjusted to produce flour with finer particle sizes and lower moisture content. The Buhler mill, on the other hand, needs to be adjusted to produce flour with bigger particle size. Both laboratory mills (Quadrumat and Buhler) need to be adjusted to produce flour that expresses FPI correctly.

The study of chemical functional groups in coal using the methods of an FTIR investigation has been carried out on five samples of bituminous coal from Bintuni Basin in West Papua, Indonesia. The FTIR spectra fitting results reveal that the aromatic chains of Steenkool Coals (SC) were dominated compared to aliphatic and oxygen-bearing. The aromatic SC’s molecular structures are mainly C=C and C-H followed by -CH. The oxygen-bearing SCs are mainly - C-O-C; and contain a small amount of C=O. The -CH2- is mainly in aliphatic SC. The apparent aromaticity (fa), Hal/Ha, (R/Cu), and other semi-quantitative parameters from the compared FTIR data indicated that the aromatic is increased with a decrease in aliphatic and oxygen-containing groups. The potential for spontaneous combustion resulting from the bituminous coal of the SC is relatively small, as more aromatic and aliphatic functional groups are detected than the oxygen-bearing functional groups.

In this paper, a hybrid technique called the homotopy analysis Sumudu transform method has been implemented solve fractional-order partial differential equations. This technique is the amalgamation of Sumudu transform method and the homotopy analysis method. Three examples are considered to validate and demonstrate the efficacy and accuracy of the present technique. It is also demonstrated that the results obtained from the suggested technique are in excellent agreement with the exact solution which shows that the proposed method is efficient, reliable and easy to implement for various related problems of science and engineering.

This paper reflects on the mobility experiences of women in African cities in COVID-19, based on research conducted both prior to and following entry into the COVID-19 ‘moment’. It draws on material collected during an ongoing action research study aimed at addressing the everyday transport and mobility challenges faced by young women living in poor peripheral communities of three African cities – Abuja, Cape Town and Tunis. The project has the specific objective of supporting young women's improved access to employment opportunities through trialling various mobility/transport-related skills interventions (based on prior in-depth analysis of mobility constraints). With the onset of COVID-19 some readjustments to the research focus and planned interventions became necessary. The research teams, together with an NGO partner, are now working to chart how young women's everyday experiences of mobility and transport - both as transport users and as transport sector workers - are changing as processes of lockdown and their relaxation evolve. The paper covers the period from early 2019 through to March 2021, and offers reflections regarding ‘lived experiences’ of mobility practice pre-pandemic, during the pandemic, and the potential longer-term mobility-related impacts for women resident in low-income neighbourhoods in a post-COVID-19 era. This leads to consideration of key policy lessons. There is potential for prioritisation of Non-Motorised Transport interventions towards a green restart that would benefit women (for instance through promoting women's cycling), and for growing women's participation as transport operators, even perhaps the usage of drones to aid women's safer pedestrian travel. But such interventions will require far greater representation of women in COVID-19 and wider transport decision-making entities than has hitherto been the case.

Fowlpox virus (FWPV) is a complex cytoplasmic DNA virus belonging to the Family- Poxviridae, Subfamily-Chordopoxvirinae and Genus-Avipoxviruses. The large size of the genome accommodates multiple g...

A semi group K is defined to be right (left) weakly regular if for all a ∈ K, a ∈ aKaK (a ∈ KaKa). In this paper, we show the following results: Let K be a W- regular semi group. Then: Any AF inter...

serological survey for the detection of antibodies to Mycoplasma mycoides subspecies mycoides (Mmm) from cattle slaughtered at Katsina Central Abattoir was conducted from March to October 2012 using competitive ELISA (CIRAD) version: P05410/04 antibody detection kit. A total of 300 cattle sera were screened for Mmm antibodies out of which 22 (7.3%) obtained from 15 (68.2%) cows and 7 (31.8%) bulls were positive. Age distribution indicated that 3 (13.6%) were less than 2 years, 11 (50%) were between 2 and 4 years of age, while 8 (36.4%) were above 4 years. The study confirmed the susceptibility of some cattle breeds from all ages and sexes to Mmm. However, middle-aged cows were shown to be more associated with the infections though not statistically significant (P˃0.01). Similarly, a total of 130 pneumonic lung tissues were used for isolation and biochemical characterization of Mmm out of which 2 (1.5%) samples one each from adult White Fulani and Red Bororo cows were found to be positive. The study established baseline information on the status of Mmm infection in Katsina State. Continuous disease surveillance and annual mass vaccination programme using effective vaccines were recommended.

Syzygium cumini L is an evergreen medicinal plant belonging to the family Myrtaceae, and is one of the important species of the genus Syzygium. S. cumini is traditionally used to treat various infections such as sore throat, bronchitis, dysentery, and other painful conditions. The aim of the current study was to evaluate fixed oil extracted from S. cumini for various in vitro and in vivo biological activities and identification of its fatty acids constituents. GC-MS analysis of the fixed oil revealed that the major constituents are palmitic acid methyl ester (56.45%) and stearic acid methyl ester (29.54%). Fixed oil isolated from S. cumini exhibited significant effect against Staphylococcus aureus, Shigella flexenari, and Bacillus subtilis with zone of inhibition of 28.09, 27.34, and 22.76 mm, respectively. In addition, the oil exhibited antifungal effect against Aspergillus flavus, Candida glabrata, Microsporum canis, and Fusarium solani with zone of inhibition of 80.77, 75.08, 70.98, and 65.56 mm, respectively. The oil also exerted analgesic potential at the dose of 10, 20, 40, and 60 mg/Kg with 35.44, 50.45, 65.98, and 80.34 % activity in acetic acid-induced writhing model. A mild muscle relaxant effect was noted in animal models. Taken all together, the fixed oil from S. cumini exhibits significant antimicrobial, antifungal and analgesic effects, which justifies the use of this plant in folk medicine.

The present study was aimed to evaluate the effect of dietary supplementation with Lactuca serriola leaves on growth performance, carcass characteristics, meat quality, and its antioxidant stability of Japanese quails. A total of eighty growing quails (1-week old) were distributed into 2 equal groups consisting of 40 birds (5 replicates of 8 birds each). The first group was fed a basal diet without Lactuca serriola leaves (0 g.kg-1 diet) and the second group received diets containing 20 g.kg-1 Lactuca serriola leaves. At age of 6 weeks, quails were slaughtered for meat and carcass examinations. The growth performance for the quails fed with Lactuca serriola leaves diet was similar to that of a control group. Carcass measurements, physical properties, and chemical composition of quail breast meat did not differ between the control and experimental group. However, the inclusion of Lactuca serriola leaves significantly increased the omega-3 polyunsaturated fatty acid content and improved breast meat lipid stability during postmortem refrigerated storage compared to the control diet. In conclusion, dietary supplementation of Lactuca serriola leaves can improve the performance of Japanese quail enrich its meat with an omega-3 polyunsaturated fatty acid, and reduce lipid oxidation during storage.

Dye-sensitized solar cell (DSSC) is getting much attention in recent years due to its low-cost fabrication feature. DSSC mimics the natural photosynthesis process that converts solar energy into electricity. To be adopted in IoT devices, DSSC needs to be flexible and versatile. In this work, flexible DSSC was fabricated from binder-free TiO2 paste. The ratios of TiO2 powder to alcohol precursor were varied. The aim was to investigate the optimum amount of TiO2 powder to ethanol and the effect of different alcohol used as precursor. Hydrochloric acid was added in the TiO2 paste in order to improve the connectivity of the particles. The corresponding mechanical integrity of the as-prepared film was studied as well. From the result, the optimum conversion efficiency achieved in this work was 2.12% where the film had a ratio of TiO2 powder to ethanol of 25 wt%.

Semisolid metal (SSM) processing is a forming process which occurs within solidus and liquidus temperatures, and it requires feedstock billets with spheroidal microstructures. In this paper, a novel gas-assisted direct thermal method (DTM) is proposed as a method to create feedstock billets with fine spheroidal microstructures. Effect of different combination parameters between pouring temperature and holding time during the gas-assisted DTM technique on the microstructure of aluminium alloy 7075 feedstock billets was investigated. Pouring of molten aluminium alloy 7075 was conducted at temperatures between 645 and 685 °C, while holding time was set between 20 and 60 s. The melt was cooled down within the semisolid temperature range in a cylindrical copper mould with the help of carbon dioxide (CO2) gas before quenching in room temperature water. Results revealed that the smallest primary phase grain size formed at the combination parameters of 645 °C pouring temperature and 20-s holding time. Furthermore, the same combination parameters also produced the highest circularity value. The addition of external CO2 gas surrounded the copper mould as a rapid cooling agent was found to have a significant improvement of 36.4% to the formation of smaller primary grain and spheroidal structure. It is concluded that the lowest pouring temperature and shortest holding time coupled with rapid cooling condition from the addition of external CO2 during DTM produced the finest and most globular structure of primary phase size.

In this paper, a combined experimental and numerical investigation was conducted to understand the characteristic performance of a thermosiphon heat pipe. The influences of various parameters, such as working fluid and heat load, on the performance of a vertical copper thermosiphon heat pipe (HP) were investigated experimentally and numerically. An artificial neural network approach (ANN) was utilized to simulate the thermosiphon heat pipe and predict the heat transfer characteristics. The ANN study shows that, having an extended predict capacity, the difficult role of HP can be successfully represented by the nonlinear structure of this simulator. The predicted values of the mean square error of 0.098% were reached for the training while the error in the experiment data is about 6.25%. Based on the ANN model, there were satisfactory agreements and less recorded errors between predicted and observed values.

The production of syngas via dry reforming of methane (DRM) has drawn tremendous research interest, ascribed to its remarkable economic and environmental impacts. Herein, we report the synthesis of K, Na, Cs, Li, and Mg-promoted Ni/La2O3 using solution combustion synthesis (SCS). The properties of the catalysts were determined by N2 physisorption experiments, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectrometry (XPS), and H2-TPR (temperature programmed reduction). In addition, their catalytic performance towards DRM was evaluated at 700 °C. The results demonstrated that all catalysts exhibited porous structures with high specific surface area, in particular, Mg-promoted Ni/La2O3 (Mg–Ni–La2O3) which depicted the highest surface area and highest pore volume (54.2 m2 g−1, 0.36 cm3 g−1). Furthermore, Mg–Ni–La2O3 exhibited outstanding catalytic performance in terms of activity and chemical stability compared to its counterparts. For instance, at a gas hourly space velocity (GHSV) of 30 000 mL g−1 h−1, it afforded 83.2% methane conversion and 90.8% CO2 conversion at 700 °C with no detectable carbon deposition over an operating period of 100 h. The superb DRM catalytic performance of Mg–Ni–La2O3 was attributed to the high specific surface area/porosity, strong metal-support interaction (MSI), and enhanced basicity, in particular the strong basic sites compared to other promoted catalysts. These factors remarkably enhance the catalytic performance and foster resistance to coke deposition. This publication was supported by Qatar University, internal grant number QUCG-CENG-19/20-7. The ?ndings achieved herein are solely the responsibility of the authors. The authors also acknowledge the technical support of Central Laboratories Unit (CLU), Center for Advanced Materials (CAM), and Gas Processing Center (GPC), Qatar University, Doha, Qatar. Scopus

Thermal analysis (TA) is a non-damaging and quick method to check the molten metal’s condition preceding to casting. This paper aims to present the relationship between fraction solid and temperature by utilising cooling curve analysis (CCA), to acquire correct processing parameters for wrought aluminium 7075 in semisolid condition. An induction furnace was used to heat a graphite crucible containing wrought aluminium 7075 alloy up to the temperature of 750 °C. A calibrated Chromel-Alumel K-type thermocouple was placed at the centre of the crucible and was submerged to 15 mm in the melt. The solidification temperature and time were measured by Data Logger GL-220. Normal, intermediate, and high cooling rate conditions were achieved when the crucible was left in an open atmosphere, in an open atmosphere with additional minimum airflow, and in an open atmosphere with the maximum airflow, respectively. It was found that the normal cooling rate was estimated at 2.23 °C/s, the intermediate cooling rate was calculated at 2.88 °C/s while the high cooling rate was recorded at 3.20 °C/s. The increase in cooling rate conditions has a significant effect on the changes of phases during solidification process where it leads to the decreased in liquidus, eutectic and solidus temperature. The microstructure feature was found to have a significant difference with the variation of cooling rates where higher cooling rate led to smaller primary grain size.

Direct glucose fuel cells (DGFCs) received great interest due to non-toxicity, low cost, and renewability. Herein, we demonstrated the synthesis of novel porous AuPtPd nanocrystals (NCs) via plausible one-pot synthesis route. This was implemented by reduction of the metal precursors with l -ascorbic acid in the presence of polyvinylpyrrolidone (PVP) as a structure-directing agent. TEM (transmission electron microscopy) images of the as-synthesized nanocrystals depicted porous nanodendritic morphology with particle size ranging from 20 to 30 nm. The catalytic performance of AuPtPd NCs was investigated towards glucose oxidation reaction (GOR) in alkaline medium compared to AuPt, PtPd, and Pt/C. The delivered maximum oxidation current density over AuPtPd was 10.1 mA cm−2, which is nearly 1.4, 1.8, and 3.5 times greater than AuPt, PtPd, and Pt/C, respectively. Additionally, the ternary electrocatalyst exhibited higher electrochemical stability compared to binary alloys and Pt/C counterparts. Furthermore, AuPtPd revealed lower Tafel slope for GOR compared to binary alloys and Pt/C which affirm enhanced GOR kinetics. The outstanding catalytic performance of AuPtPd NCs was attributed to the synergistic effect of the alloying elements and the high anti-poisoning effect of Au and Pd metals which facilitates the adsorption of surface hydroxyls (OH)ads on the catalyst active sites and enhances the oxidation kinetics.

Background: Plastic bottles are widely used by people to feed their infants when breastfeeding is not possible. Bisphenol A (BPA), an endocrine disruptor is widely used in the manufacturing of plastic wares and is leached out from these plastic wares on exposure to high temperature, changed pH, or cleaning the plastic wares by harsh detergents.Purpose: Feeding through plastic bottles over prolong duration is expected to expose the infants to leached BPA. Hence the present study was taken up to compare the effects of breastfeeding and plastic bottle feeding on biochemical parameters in infants and also detect for the presence of free BPA or its metabolite in the infants.Methods: Biochemical tests like lipid profile, liver function tests, creatine-kinase–MB (CK-MB), serum urea, serum electrolytes were performed on blood samples obtained from infants who were breastfed and plastic bottle fed. Further, plasma and urine samples of the infants were subjected to Liquid chromatography-mass spectrometry analysis for detecting free BPA and BPA glucuronide.Results: Biochemical changes in form of raised triglycerides, cholesterol, low-density lipoproteins, very low-density lipoproteins and increase in CK-MB, serum urea were observed in plastic bottle fed infants. BPA glucuronide was also detected in the urine of these infants. Free BPA was not detected in plasma or urine samples of the infants except in one plasma sample from bottle-fed group.Conclusion: Plastic bottle feeding may lead to toxic changes in the functioning of organs which manifest as altered biochemical parameters.

This work presents various essential features and design aspects of a single-inductor, common-output, and multi-string White Light Emitting Diode (WLED) driver for low-power portable devices. High efficiency is one of the main features of such a device. Here, the efficiency improvement is achieved by selecting the proper arrangement of WLEDs and a proper sensing-circuit technique to determine the minimum, real-time, needed output voltage. This minimum voltage necessary to activate all WLEDs depends on the number of strings and the forward voltage drops among the WLEDs. Advanced CMOS technology is advantageous in mixed-signal environments such as WLED drivers. However, this process suffers from low on-resistance, which degrades the accuracy of the current sinks. To accommodate the above features and mitigate the low node process issue, a boost-converter that is single output with a load of a three-string arrangement, with 6 WLEDs each, is presented. The designed driver has an input voltage range of 3.2–4.2V. The proposed solution is realized with ultra-low power consumption circuits and verified using ADS tools utilizing 40 nm 1P9M TSMC CMOS technology. An inter-string current accuracy of 0.2% and peak efficiency of 91% are achieved with an output voltage up to 25 V. The integrated WLED driver circuitry enables a high switching frequency of 1MHz and reduces the passive elements’ size in the power stage.

The use of flexible bronchoscopy (FB) with bronchoalveolar lavage (BAL) to diagnose and manage pulmonary complications has been shown to be safe in adult cancer patients, but whether its use is safe in pediatric cancer patients remains unclear. Thus, to describe the landscape of FB outcomes in pediatric cancer patients and to help define the populations most likely to benefit from the procedure, we undertook a retrospective review of FBs performed in patients younger than 21 years treated at our institution from 2002 to 2017. We found that a greater volume of total fluid instilled during BAL was significantly associated with increased probabilities of positive BAL culture (p=0.042), positive bacterial BAL culture (p=0.037), and positive viral BAL culture (p=0.0496). In more than half of the FB cases, findings resulted in alterations in antimicrobial treatment. Our study suggests that for pediatric cancer patients, FB is safe, likely provides diagnostic and/or therapeutic benefits, and has implications for treatment decisions.

In the present study, the in vitro antifungal potential of seven Lamiaceae herbs against Fusarium oxysporum f. sp. cyclaminis were investigated. On the basis of the results, the in vivo antifungal effects of sage water extract on Fusarium wilt in cyclamen were evaluated, and the antifungal properties of the extract were identified. Among the seven herbs, sage water extract (0.5% and 2%, w/v) showed considerable suppression of F. oxysporum f. sp. cyclaminis in vitro. For the in vivo evaluation, cyclamen plants were treated with sage water extract (20%, w/v) two times and inoculated with F. oxysporum f. sp. cyclaminis. Six weeks after the inoculation, a lower disease incidence and disease severity indices were observed in roots and shoots of the treated plants. These effects could be attributed to reduced Fusarium populations in the plant roots because of the fungistatic and fungicidal effects of the sage extract. Consequently, the dry weights of the shoots and roots treated with the sage extract were higher than those of the control. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS) was performed, and caffeic acid and rosmarinic acid were identified to be important metabolites in the sage water extract. In addition, the antifungal effects of these compounds against F. oxysporum f. sp. cyclaminis were confirmed using an in vitro test. Thus, it can be concluded that sage water extract can suppress Fusarium wilt in cyclamen and the two identified compounds play key roles in the antifungal properties of sage.

Background: Parkinson's disease (PD) is the second-most common neurodegenerative disorder known primarily by its motor symptomatology. These motor manifestations are also hypothesised to affect the respiratory muscular function of PD patients contributing to restrictive pattern of ventilatory dysfunction. Previous reports attempting to detect these abnormalities through spirometric assessments have been inconclusive. Attempts at reversal of the restrictive abnormalities by levodopa therapy too, have yielded conflicting results. Objectives: This study aims to classify spirometric abnormalities in asymptomatic PD patients after levopopa withdrawal and document changes after levodopa replacement. Methods: Thirty-six non-smoker PD patients without pre-existing respiratory abnormalities were enrolled. Their standard spirometric values- FEV1, FVC and FEV1/FVC, were noted before and after their morning levodopa dose. Results: Nineteen patients had abnormal PFT values at baseline - 14 restrictive and 5 obstructive defects. Fourteen patients showed improvement in their pulmonary performances after dopamine administration with 6 showing complete reversibility. Statistically significant improvement in the post-levodopa FVC values was seen in patients with restrictive disorder (P value=0.04) but not for obstructive disorders. Discussions: This pilot study characterised that 39% of PD patients had restrictive ventilatory defects prior to morning dopamine administration. Of these, 40% showed improvement after levodopa administration. Conclusion: Restrictive defects are common in PD patients which are evident on routine spirometric screening. These defects are reversible on levodopa administration.

The significance of this study is heightened by the fact that critical thinking (CT) is vastly seen as a major objective of higher education and the basis for the development of learning outcomes. Thus, this quasi-experimental aims at promoting and assessing students’ critical thinking skills (CTSs) through argumentative essay-writing. It also investigates the correlation between CT and essay-writing skills. The main question addressed is: what is the effectiveness of promoting CTSs through argumentative essay-writing among English major students in terms of interpretation, analysis, evaluation, inference, and explanation? An instructional material was designed and implemented in classroom teaching to enhance CT. The study was conducted on 98 English major male participants enrolled in an essay-writing course at Prince Sattam bin Abdulaziz University (PSAU), Saudi Arabia. The participants were randomly assigned to either intervention (n =49) or control (n =49) groups. Quantitative-qualitative methods were employed. Pretest and posttest were applied to both groups. The Facione and Facione (1994) CT scoring rubric was utilized for assessing CTSs. Findings revealed that CT and essay-writing skills are significantly positively correlated. Assessment of students’ essays denoted that the intervention group significantly surpassed the control in the five CTSs: "interpretation, analysis, evaluation, inference, and explanation" (Facione 1990, p. 8). It can be concluded that explicitly teaching CTSs through essay-writing can be effective in the development of these skills. The study recommended that further studies be implemented in different universities and also using other CT definitions and skills, and comparisons between the findings could be made.

The design and fabrication of novel metal-supported catalysts for energy conversion and heterogeneous catalysis is a pivotal theme. Herein, we present the synthesis of bimetallic palladium nanoalloys supported on halloysite nanotubes, PdM@HNTs, where M = Co, Cu, and Ni and their catalytic performance towards CO oxidation. The synthesis procedure involves simple co-reduction of the metals precursors using NaBH4 on halloysite nanotubes support. The synthesized catalysts retain the tubular morphology of halloysite support with surface area of 90–107 m2 g−1. Transmission electron microscopy (TEM) revealed smaller size for bimetallic nanoparticles (6–8 nm) compared to Pd (14 nm). PdNi displayed the highest catalytic activity towards CO oxidation. Moreover, PdCo and PdNi demonstrated enhanced CO oxidation kinetics compared to PdCu and PdNi as revealed from the calculated activation energies. DFT calculations revealed that the order of catalytic activity is PdNi > PdCo > PdCu > Pd which is in agreement with the experimental results and that the adsorption energy of CO2 on the different catalysts has no apparent role in the whole activity of the catalyst. In conclusion, PdM@HNTs catalysts expressed homogeneous distribution for metallic nanoparticles as well as high dispersion and expressed promising potential to be applied in real flare control processes. This work was made possible by NPRP Grant no. NPRP 8-1912-1-354 from the Qatar National Research Fund (a member of the Qatar Foundation). The statements made herein are solely the responsibility of the authors. Appendix A Scopus