Miracle-dz/UniFAR-FTUs huggingface dataset:
Students' reasoning about basic chemical thermodynamics and chemical bonding: what changes occur during a context-based post-16 chemistry course?

A longitudinal study of 250 students following the Salters Advanced Chemistry (SAC) course probed a range of chemical ideas including the exothermicity of bond formation and the development of thinking about covalent, ionic and intermolecular bonds. Students responded to the same diagnostic questions on three occasions: at the start, after eight months and sixteen months of a twenty-month course. At the start, many students demonstrated misunderstandings about these chemical ideas, but in general their understanding improved as the course progressed. By the end of the study, about half knew that bond making is exothermic. Initially, few described covalent bonds accurately or understood hydrogen bonding. A majority gave responses at the final survey which were in line with ideas and language a chemist may use. Students attributed changes to the use of context-based materials including a drip-feed approach which allowed their understanding to develop over time. However, some aspects of chemical bonding, including ionic bonding and intermolecular bonds other than hydrogen bonds remained problematic for students despite explicit teaching. The findings have implications for post-16 chemistry teaching, suggesting that a review of teaching strategies is needed in some areas.
VISCOUS FLOW OVER PERIODIC SURFACES

Laminar flows confined between parallel surfaces, one of which is periodically “rough,” are studied. The effect of surface roughness has been computed for both drag and pressure flows. A basis of comparison is defined so that the effect of roughness on the rate of flow parallel to the surfaces can be quantified. The external flow penetrates the roughness elements to a degree that depends upon the parameters that characterize the roughness. The presence of a pressure gradient exerts a strong influence on the degree of penetration of the roughness. Experiments on the terminal velocity of an axisymmetric grooved cylinder falling through a viscous liquid within a closed concentric tube are presented, and the results agree well with the computational studies.
To study the effects of Securigera securidaca (L.) seed against alloxan-induced hyperglycemia

In the present study, the anti-hyperglycemic and antioxidant potential of the Securigerasecuridaca (L.) seed suspension in alloxan-induced hyperglycemic rats was investigated. The male Wistar rats (180 to 220 g) were divided in three groups and treated orally for 4 days as follow: group I, the control, was fed 10 ml/kg/day of distilled water, groups II and III were gavaged 2 and 4 g/kg/day of S. securidaca (L.) seed suspension, respectively. One hour after final feeding, alloxan was injected subcutaneously (70 mg/kg B.W). At the end of the experimental period (after 24, 48 or 72 h of alloxan injection), antioxidant activity, fasting glucose and insulin levels were determined. The administration of suspension (2 g/kg/d or 4 g/kg/day) significantly reduced elevated serum glucose concentration induced by alloxan and that was prominent following 24, 48 and 72 h of alloxan injection. Serum antioxidant activity in the low (2 g/kg/d) and high (4 g/kg/d) doses of suspension treated rats was significantly higher at 24, 48 and 72 h after alloxan injection as compared to control rats. These results indicate protective effect of S. securidaca (L.) suspension against alloxan-induced hyperglycemia and oxidative stress in rats. Key words: Hyperglycemia, alloxan, Securigera securidaca, glucose, antioxidant activity.
On the time of lasing onset and the end-effect of a soft x-ray laser device using a capillary z-pinch discharge

We have measured the time of lasing onset of a capillary z-pinch discharge used for Ne-like Ar soft x-ray laser generation. It was found that for a relatively long plasma, the relationship between the time of lasing onset and the filling pressure of the Ar gas agrees, in trend, with that predicted by simulation. An interesting result was observed: the time of lasing onset becomes delayed when the length of the capillary becomes shorter, which is considered to be caused by an end-effect of the capillary on the pinching process. This also implies that a relatively long capillary is favourable for obtaining a plasma column of uniformity, and thus for reducing the relative absorption of laser power.
Decomposition pathways of dinitramic acid and the dinitramide ion

Gas-phase dinitramic acid HN(NO2)2 [HDN] decomposes along two pathways, one involving a molecular rearrangement, HDN→HNO3+N2O, and a second initiated by N–N bond fission, HDN→HṄNO2+ṄO2. A molecular rearrangement pathway for the gas phase dinitramide ion N(NO2)2−[DN−], DN−→NO3−+N2O, can also occur. The rates and pathways for the decomposition of HDN and the corresponding dinitramide ion are subjects of the present work. Density functional theory calculations at the B3LYP/6-311G(d,p) level are carried out to determine the geometries, vibrational frequencies, and zero-point energies of the reactants, products, and transition states involved in the gas phase decomposition of HDN. These geometries are then used in the modified Gaussian-2 method (G2M) to calculate energies to sufficient accuracy to predict the rates of the decomposition reactions. The lowest energy pathway for N2O formation initially involves an internal proton transfer in the HDN molecule. The system then passes through a four-center transitio.
Photocatalytic degradation of diazinon in aqueous solution by platinized TiO2

The photocatalytic degradation of diazinon, which is one of phosphorothiate insecticides, was carried out in the presence of platinized TiO2 photocatalyst. The degradation rate was strongly influenced by the pH, catalyst dosage and light intensity. In addition, platinization was found to increase the rate of diazinon degradation. When 0.5 wt% of platinum was deposited onto the surface of TiO2, an initial diazinon concentration of 30 mg L-1 was completely degraded after 30 min. Furthermore, the first-order rate constant for diazinon degradation by Pt-TiO2 was 2.5 times higher than P-25 TiO2. The decrease of TOC as a result of mineralization of diazinon was observed during the photocatalytic process. The degree of diazinon mineralization was about 88% under UV irradiation after 30 h. The formations of sulfate, phosphate, nitrate and ammonium ions as end-products were observed during the photocatalytic system. The decomposition of diazinon gave six kinds of intermediate products. The degradation mechanism of.
Antifungal Potential of Trichoderma virens Secondary Metabolites, Botanicals and Fungicides against Exserohilum turcicum causing Turcicum Leaf Blight of Maize

Maize (Zea mays L.) is considered to be the most important cereal crop which ranks third after wheat and rice in India. Maize is cultivated widely around the world because of its greater adaptability to varied environmental condition as well as its ability to produce higher yield. From last few decades there has been a rapid increase in the area, production and productivity of this crop due to the introduction of high yielding indigenous varieties, exotic hybrids and also the use of improved farm machineries, chemical fertilizers and chemical pesticides. However, these agricultural inputs also lead the maize crop vulnerable to pests and diseases in the farmer's field. International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 9 Number 11 (2020) Journal homepage: http://www.ijcmas. com
Exploring the Effect of Using WhatsApp on Saudi Female EFL Students' Idiom-Learning

The study aimed at investigating the effect of using WhatsApp-based learning activities on developing idiom knowledge among Saudi university English as a foreign language (EFL) students compared to conventional method. It also examined the students’ perceptions towards the application of WhatsApp in idiom-learning. The rationale for conducting this study is to provide students with useful learning tools that may improve their idiomatic knowledge and also help them to practice English idioms anytime and anywhere outside the classroom. It also aimed to help teachers to streamline EFL instruction, making it more efficient, effective, and user-friendly. As such, the main research questions are what is the effect of WhatsApp-based learning activities on developing university female EFL students? and what are Saudi female EFL students’ perceptions on learning idioms using WhatsApp? To answer these questions, 70 EFL female students in the Department of English Language and literature at Imam Mohammad ibn Saud Islamic University (IMSIU) involved in the study. They were assigned into two groups; experimental group, who was taught English idioms via WhatsApp-based learning activities, and control group, who was taught English idioms conventionally in classroom. Two instruments were used to collect the data; a pre-post idioms achievement test and a post-study questionnaire. The findings demonstrated that the experimental group significantly outperformed the control group in idioms achievement post-test. Moreover, the results showed that the majority of the experimental group had a positive perception towards learning English idioms via WhatsApp.
Revisiting Grammar Teaching in a Saudi EFL Context: Teachers’ Perceptions and Practices

In language, meaning is conveyed and received through words and grammar. A phrase or a sentence is not a random collection of words. In the absence of grammar, words hang together without any real meaning. Thus, grammar plays an essential role in language teaching. With adequate grammar explanations in meaningful contexts and practice, some serious errors in learners' language can be avoided. This study aimed at examining the relationship between teachers’ perceptions of grammar teaching and their actual practices in a Saudi EFL context. Questionnaires and classroom observation checklists were used to gather information about teachers' perceptions of grammar teaching and to compare that with their practices. The paper sought to find answers to these questions: 1) What are teachers’ perceptions of grammar teaching? 2) Do teachers’ perceptions of grammar correlate with their actual teaching in EFL classes? 3) What are teachers’ perceptions of problems, if any, hindering their practice of grammar teaching? The sample consisted of 23 teachers who completed a questionnaire discussing their perceptions of grammar teaching and practice. Six of these teachers were observed teaching grammar in classes. The findings revealed that there was a negative correlation between teachers' perceptions of grammar teaching and their perceptions of their grammar classes. Also, there was a negative correlation between teachers' perceptions of grammar teaching and the observed classes. However, teachers' perceptions of their classes were mostly reflected in observation cards, and they were positively correlated. Further, the study revealed teachers' tendency towards traditional methods of teaching where the meaningful practice was overlooked.
Antecedent control on active ice sheet retreat revealed by seafloor
geomorphology, offshore Windmill Islands, Antarctica

Abstract. Understanding past retreat of Antarctic ice margins provides valuable insight for predicting how ice sheets may respond to future environmental change. This study, based on high resolution multibeam bathymetry from the nearshore region of the Windmill Islands, East Antarctica, reveals a style of retreat that has been rarely observed on the Antarctic margin. A suite of seafloor features record the final retreat stages of a relatively thin, and increasingly fractured tidewater glacier confined within narrow troughs and embayments, forming a suite of features more typical of warm-based ice, but occurring here in a region of cold-based ice with limited surface meltwater production. The pattern of moraines and crevasse squeeze ridges, reveals strong topographic and substrate control on the nature of ice sheet retreat. Topographic control is indicated by fine-scale variability in the orientation and distribution of glacial landforms, which show that the seabed topography influenced the shape of the ice margin, caused deflection of ice flow and led to the separation of flow downstream from topographic highs. The availability of water saturated marine sediments within the troughs and depressions also had a profound effect on the landform record, facilitating the construction of moraines and crevasse squeeze ridges within topographic lows, corresponding to areas of modern sediment accumulation. Surrounding areas of crystalline bedrock, by contrast, acted as sticky spots and lack a well-developed landform record. This seafloor glacial record emphasises the importance of understanding the bed topography and substrate when predicting the nature of ice margin retreat and provides new perspectives for understanding the stability of the East Antarctic margin.
Structural elucidation of novel mixed ligand complexes of 2-thiophene carboxylic acid [M(TCA)2(H2O)x(im)2] [x=2 M: Mn(II), Co(II) or Cd(II), x=0 Cu(II)]

Abstract Novel mixed ligand complexes containing thiophene-2-carboxylic acid (HTCA) and imidazole (im) ligands, [M(TCA)2(H2O)2(im)2] (M: Mn, Co, Cd) and [Cu(TCA)2(im)2] were obtained. The complexes were characterized by X-ray single crystal diffraction. Also, spectroscopic (IR and UV-Vis), magnetic and thermal properties were investigated. The thiophene-2-carboxylate acted in a monoanionic monodentate manner and bonded to the metals via its carboxylate oxygen. The im ligands bonded to the metals via hydrogen free nitrogen atoms. The geometry around the metal centers was octahedral [MO4N2] for Mn(II), Co(II) and Cd(II) complexes and square-planar [CuO2N2] for the Cu(II) complex. Due to intermolecular interactions in the solid state, the Co(II), Mn(II) and Cd(II) complexes showed three-dimensional networks, while the copper complex was a one-dimensional network. In consideration of the anhydrous form of the complexes, the thermal stability of the complexes was of the following order: Co (273°C)>Cu (229°C)>Cd (175°C)>Mn (167°C).
Anti-microbial activities of ionic liquids

Ionic liquids (ILs) are shown to display anti-microbial activity with the activities being greatly affected by alkyl chain lengths. Shorter substituents on the cation result in a lack of activity against cocci, rods and fungi. ILs containing 10, 11, 12 and 14 carbon atoms in an alkoxy group show very high anti-microbial activities. The use of microorganisms in the IL require consideration of their minimum inhibitory concentration (MIC) values.
Short-term outcomes of laparotomy in the two teaching hospitals of gulu university, northern uganda

Purpose: The purpose of this study was to examine the clinical indication for laparotomy, the intra-operative fi ndings and the 30 days post-operative outcome of laparotomy in Gulu university teaching hospitals. Methods: Using an approved protocol, a six month descriptive longitudinal study was conducted on patients undergoing laparotomy in the two main Gulu University teaching hospitals of St. Mary’s Hospital Lacor and Gulu regional referral. Using a sample size of 66, cases were recruited consecutively, clerked, investigated and conventionally prepared for surgery. Intra-operative diagnosis was ascertained as well as the operative procedure and post-operatively the patients were followed up for 30 days complications including death. Results: Overall, the mean age was 35.04yrs (SD+/16.522), but there were more males (59.4%) than females (40.6%). There was a statistically signifi cant positive correlation between the clinical diagnosis and the intraoperative fi ndings (r = 0.405, P value = 0.001). Within the 30days, the most frequent complication observed was surgical site infection (SSI) (20%, n=13), followed by wound dehiscence (17.2%, n=11), crude mortality rate was 15.6%, (n=10) and complication requiring emergency reoperation (10.9%, n=7). Ileal perforations tended to have bad outcomes. Age of patient was found to be a signifi cant factor in determining the outcome. Conclusion: Descriptive longitudinal study on both elective and emergency laparotomy is possible in our setting. Whereas patients’ age is an important factors in determining outcome and ileal perforation tend to do better if prioritized with ileostomy, overall the 30days mortality rate for laparotomy was 15.6%. Research Article Short-term outcomes of laparotomy in the two teaching hospitals of gulu university, northern uganda Amone D1, Okello TR1*, Okot C2, Kitara DL3, Mugabi P3 and Ogwang DM4 1Department of Surgery, Graduate Trainee and Assistant lecturer in Surgery and Anatomy, Gulu University, Senior Lecturer and Head Lira University, Uganda 2Professor and Head Department of Surgery, Medical offi cer Special Grade, Gulu Regional Referral Hospital and Associates. Gulu University, Uganda 3Lecturer, Department of Surgery, Gulu University, Uganda 4Senior Consultant Surgeon and Institutional Director St. Mary’s Hospital Lacor, Uganda Received: 15 October, 2020 Accepted: 04 November, 2020 Published: 17 November, 2020 *Corresponding author: Tom Richard Okello, Senior Lecturer and Head of Surgery Department, lira University, Uganda, Tel: +256772473510; Email:
Sleep habits as predictors of psychological health in healthcare professionals

Título: Los hábitos de sueño como predictores de la salud psicológica en profesionales sanitarios. Resumen: El objetivo de la investigación fue estudiar los hábitos de sueño y la salud psicológica de profesionales del sector sanitario, así como analizar las relaciones entre ambas variables. La muestra contó con 511 trabajadores de hospitales públicos de la Comunidad de Madrid. La salud psicológica fue evaluada con el Cuestionario GHQ-28; los hábitos de sueño a través del Cuestionario CHAS, además, se recogieron datos sociodemográficos como edad, sexo, puesto de trabajo, categoría profesional. Los resultados mostraron diferencias estadísticamente significativas en síntomas somáticos, salud psicológica y estabilidad en hábitos de sueño. Los análisis de regresión indicaron que calidad del sueño y somnolencia diurna son las variables más relacionadas con las dimensiones de salud, especialmente con la ansiedad/insomnio y síntomas somáticos. Estos los resultados ponen de manifiesto las diferencias entre hábitos de sueño y salud percibida en personal de enfermería y facultativos. En conclusión, la población sanitaria presenta mayor prevalencia en malestar psicológico, peor calidad de sueño e inestabilidad en las horas de sueño. Deterioro del sueño, somnolencia y síntomas somáticos son más frecuentes en personal de enfermería que en el resto de profesionales sanitarios. Palabras clave: profesionales sanitarios; hábitos de sueño; salud psicológica; categoría profesional. Abstract: The aim was to study the sleep habits and the psychological health of professionals in the health sector, as well as to analyse the relationships between both variables. The sample consisted of 511 workers from public hospitals in the Community of Madrid. Psychological health was evaluated using the GHQ-28 Questionnaire; and sleep habits with the CHAS Questionnaire. In addition, sociodemographic information was collected, such as age, sex, job position and professional category. The results showed statistically significant differences in somatic symptoms, psychological health and stability in sleep habits. Regression analysis indicated that sleep quality and daytime sleepiness are the variables most related to health dimensions, especially with anxiety/insomnia and somatic symptoms. These results reveal the differences between sleep habits and perceived health in nursing staff and doctors. Finally, healthcare workers present a higher prevalence of psychological distress, poor sleep quality and instability in sleep hours. Sleep impairment, somnolence and somatic symptoms are more frequent in nursing staff than in other healthcare professionals.
Methods to investigate fertilization as a means to improve growth and sugar yield of sugar maple

Abstract In a randomized block experiment, NPKCa fertilizers were applied annually for 5 years to a mature sugar maple (Acer saccharum Marsh.) woodlot in southern Ontario. Trees selected from 3 crown classes were fitted with dendrometer bands, tapped for sap and analyzed for foliar starch and nutrients and sap nutrients. Crown classes responded differently to the fertilizers. Trees which responded significantly in diameter growth did not respond the most in sugar yield. Effects of the fertilizer treatments on sugar yield were shown to be significant when the area of crown overlap of competing trees was subtracted from the crown area of crop trees. Foliar analysis and DRIS showed which nutrients were in demand after fertilizer applications. Sap analysis showed significant relations between sap nutrients and between sap nutrients and diameter growth. Starch analysis showed significantly higher foliar starch concentrations after potassium fertilization than after other fertilizer treatments.
Effect of Mitigating Heat Stress in Dry Period of Surti Buffaloes on Erythrogram, Leukogram and Neutrophil to Lymphocyte Ratio during Subsequent Lactation

Dry period is a critical phase in lactating bovines. After completing the previous lactation the body becomes depleted of reserves. For optimum production there should be minimum number of open days in bovines. So normally during dry phase dairy bovines are also in advanced gestation stage. During this period there is involution of udder followed by rapid proliferation of mammary gland tissues as a preparatory measure for International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 9 Number 11 (2020) Journal homepage: http://www.ijcmas. com
Occupational Licensing and Skills Mismatches

The Center for Growth and Opportunity at Utah State University is a university-based academic research center that explores the scientific foundations of the interaction between individuals, business, and government. This working paper represents scientific research that is intended for submission to an academic journal. The views expressed in this paper are those of the author(s) and do not necessarily reflect the views of the Center for Growth and Opportunity at Utah State University or the views of Utah State University.
Single Polymer Chains into Single-Chain

The folding of certain proteins (e.g., enzymes) into perfectly defined 3D 17 conformations via multi-orthogonal interactions is critical to their function. Concerning 18 synthetic polymers chains, the “folding” of individual polymer chains at high dilution via 19 intra-chain interactions leads to so-called single-chain nanoparticles (SCNPs). This review 20 article describes the advances carried out in recent years in the folding of single polymer 21 chains into discrete SCNPs via multi-orthogonal interactions using different reactive chemical 22 species where intra-chain bonding only occurs between groups of the same species. First, we 23 summarize results from computer simulations of multi-orthogonally folded SCNPs. Next, we 24 comprehensively review multi-orthogonally folded SCNPs synthesized via either non25 covalent bonds or covalent interactions. Finally, we conclude by summarizing recent research 26 about multi-orthogonally folded SCNPs prepared through both reversible (dynamic) and 27 permanent bonds. 28
Some Effects of High Air Temperatures and Muscular Exertion upon Colliers.

This paper deals with the work undertaken by the author while he was Tyndall Research Student of the Royal Society. The investigations fall under the following four distinct headings:— 1. The Food Consumption of Colliers and its relation to Underground temperature conditions. 2. Respiratory Exchange of a Collier during work. 3. Relation of High Temperatures and Work to Sweating. 4. Miners’ Cramp. Each branch of investigation is related to underground temperature conditions, and has in consequence a bearing upon each of the other sections.