Mathematical cognition is a complex mental activity that involves various functions of the brain most especially identification of quantities, comparison of such quantities and calculations among others. Understanding mathematics involves mathematical cognition as it is heavily informed by the learner’s ability to reason at an abstraction level because mathematics is relatively abstract. Mathematics is a systematic reasoning and representations of specified quantities. The representational foundation of mathematics is bounded in arithmetic and numerical rules. In mathematical cognition the main reference is in how mathematics tends to be acquired by the human mind and not the mathematics that the human mind acquire in response to a given stimuli. This article attempts to discuss the various research out-puts that have been documented on how children cognitively interact with mathematical information. It also investigates important knowledge bases that elementary mathematics teachers ought to possess in order to engage learners’ mathematical cognition at optimal levels.
The interaction of Th (IV), UO2 (VI), Sm (III) and Er (III) with (CHPHDM) or (CHPAAA) as primary ligand and 2-amino-4-methyl. pyridine (2-AMP) as secondary ligand were studied in 75% (v ̷ v) dioxane–water by pH-metric titration at different temperature viz: 10, 20, 30 and 40oC and ionic strength 0.10 M KNO3. The values of stability constants and thermodynamic parameters were determined. The values of The constants were divided into their electrostatic (el) and non-electrostatic (non). The enthalpy of mixed complex ΔHMLn is greater than the enthalpy of the binary complex ΔHMA or ΔHML. The value of -ΔHnon > -ΔHel for binary and ternary complexes. The values of ΔHnon reflected the degree of covalence in the complexes and this indicates that the intermolecular covalent leads formation being ruled out.
During evaporation as the proportion of water decreases in the black liquor the viscosity and solid content of the black liquor increases. In soda pulping of wheat straw silica can precipitate out of the black liquor and result in scaling in the evaporators and can cause black liquor firing problem in the recovery boiler due to increase in viscosity. As the viscosity increases the black liquor becomes more difficult to handle. Because of the high viscosity of the black liquor it is often difficult to obtain sufficiently high concentration by evaporation. The reduction in Evaporator product liquor viscosity to the extent of 350-450cp maintaining 64- 65% solids observed for 70:30 & 65:35 blend of straw: wood by maintaining higher residual active alkali of 6.5-7.5gpl in evaporator feed by recirculation of white liquor of 90 gpl as total titratable alkali(TTA) at 3.1m3/hr flow rate resulting in steam saving in evaporator, increase in evaporation rate and reduction of steam consumption per metric ton of solids ,maintain lower viscosity compared to use of weak white liquor at evaporator feed
Abstract:\nPurpose: This study aimed to compare the effects of pharmacological control between myopic children treated with 0.2% atropine combined with 0.15% brimonidine and those treated with 0.2% atropine alone. \nMethods: One-hundred children (200 eyes in total) were divided into group A and B. Group A (100 eyes) received 0.2% atropine combined with 0.15% brimonidine once every night and group B (100 eyes) received only 0.2% atropine once every night. Changes of uncorrected vision, cycloplegic refractive errors, axial length (AL), and intraocular pressure (IOP) at baseline, 6-month, and 12-month after the treatments were compared. \nResults: All subjects completed one year of follow-up. There were no significant differences in IOP and AL in both groups after 1-year treatments. Group A had significant reduction of refraction errors (-2.50±0.6 at baseline to -1.50±1.54 after 1-year treatment) and improvement of uncorrected vision (0.30±0.15 at baseline to 0.07±0.05 after 1-year treatment). Group B also had significant reduction of refraction errors (-2.55±1.6 at baseline to -2.00±1.84 after 1-year treatment) and improvement of uncorrected vision (0.32±0.17 at baseline to 0.17±0.08 after 1-year treatment). In comparison of 2 groups, group A revealed favorable effects of reduction of refraction errors and improvement of uncorrected vision than group B.\nConclusions: Children treated with 0.2% atropine combined with 0.15% brimonidine revealed better outcomes in decreasing the refraction errors and improving the uncorrected vision than those treated with 0.2% atropine alone after 1-year follow-up. It seems that 0.2% atropine combined with 0.15% brimonidine once at bed-time enhances the efficacy of myopia control.
Historically, the development of new analytical methods has focused on improving properties as accuracy, sensitivity, and selectivity. However, there is a growing interest in considering the impact of analytical labor on the environment. In this work, topics of Green Chemistry and Engineering have been adapted to the analytical context in order to integrate a framework to assess how green it is from an analytical task to the analytical process in its entirety, in a clear and simple way to facilitate the transition of the discipline towards sustainability.
In soda pulping of wheat straw silica precipitates out of the black liquor resulting scale formation in the evaporators and increase in its viscosity. As a consequence, it becomes difficult to handle the black liquor and cause firing problem in the recovery boiler.. Because of the high viscosity of the black liquor it is often difficult to obtain sufficiently high concentration by evaporation. An empirical approach is extended in laboratory scale for reduction in viscosity of various solids concentration of Punjab region wheat straw black liquor without adopting the conventional approaches like desilication of black liquor and specialized thermal treatment by blending of wheat straw with Eucalyptus hybrid hardwood black liquor at different temperatures.
ABSTRACT This article reviews the metallurgical industry of Kazakhstan and the problems of reducing its cost-effectiveness. Analyzing the current situation in the industrial sector of Kazakhstan, as well as based on international experience, the article examines the increasing economic efficiency of enterprises in the metallurgical industry through active innovation. The main conductor of the innovative development of the industry are the large enterprises have greater flexibility to market conditions and of high performance. In modern conditions given enterprises can become an alternative to enlargement of metallurgical production, increase its efficiency and to create conditions for the production of products with high added value. The article describes the advantages of these enterprises to the classic metal works, given their technical and economic indicators, analyzes the global experience and the need for active development in Kazakhstan
This study was designed to investigate the effect of different concentration of pomegranate peel extract on chemical and microbiological quality of frozen bovine minced meat. Sixteen equal parts of minced meat were used as follows: one normal control, three POMP extract- treated parts (0.5, 1.5, and 3 % ), three inoculated parts (S. typhimurium, S. aureus or E. coli) and nine parts (3 POMP concentrations + 3 microorganisms inoculated, i.e. 3 X 3). Physical properties, chemical composition and microbiological count were performed at 0, 7, 15, 30 and 45 days of freezing at -18 ºC. The results showed that POMP aqueous extract maintained protein %, ash%, pH, thiobarbituric acid (TBA) number and total volatile nitrogen (TVN) at levels higher than non-treated non polluted samples and maintained TBA and TVN at levels lower than non-polluted or S. typhimurium or S. aureus but not E. coli - polluted samples. The results revealed that POMP has completely prevented survival of S. typhimurium and S. aureus but not E. coli during storage periods. In conclusion, POMP dried watery extract could be useful as natural preservative for bovine minced meat, since it maintained chemical and microbiological quality of minced meat.
In all cancer incidences among women, breast cancer comprises 10.4% as the second most common type of non-skin cancer after lung cancer. The aim of this study is clearing the ctotoxic effect of Curacin A as anticancer agent. Concentrations of 10, 20 and 40 nmol/L Curacin A were administered to broad cell lines (breast, ovarian, prostate and leukemia) for 24 hs. DNA content in breast carcinoma MCF-7 was monitored by flow cytometry in the presence and absence of Curacin A. Microtubule of MCF-7 cell was seen by immunofluorescence using DMSO assay. Curacin A appeared a potent cytotoxicity against breast, ovarian, prostate and leukemia-derived cell lines. In contrast, Curacin A was noncytotoxic to normal human cell line GM05654. Curacin A (40 nmol/L) arrested MCF-7 cells at G2-M phase with accumulations percent 78%. Further immunostaining study with DAPI appeared blue disordered and rare long microtubules after administration of MCF-7 cells to >50 nmol/L of Curacin A. Our results revealed arresting cell cycling at the G2-M phase in a dose-dependent manner. The current investigation revealed disruption of the microtubule assembly inside the cancer cells and preventing the formation of mitotic spindle by treatment with Curacin A.
The present study aimed to assess the physicochemical and bacteriological properties of bottled water in the Arab world. The analyzed water brands comprised Aquafina, Baraka, Dasani, Hayat, Nestle Pure Life, Safi, Siwa and Aman Siwa (Egypt); Zamzam, AlGhazal, Exthra Hilwa, Hana and Qurah AlJouf (Saudi Arabia); Marwa, Nestle and Ghadeer (Jordan); Fourat, Safia, Sabrine (Tunisia). The cations and anions were analyzed by DR5000 UV-VIS spectrophotometer (HACH). Water turbidity was determined by 2100Q01 HACH portable Ultrameter. Total coliforms and E. coli were asserted by Colitag medium. Each brand of water had its own taste and attained a specific chemical nature. All water brands were free of bacteria. Municipal water was more turbid than bottled water. There was marked variation in the levels of the pH, electrical conductivity, bicarbonates, total dissolved solids, chlorides, sulphates, minerals and turbidity among studied water brands. Qurah AlJouf water attained the highest amount of total dissolved solids, whereas Zamzam water contained the highest level of sodium, chlorides and sulphates. There was significant variability in the water ingredients among different water brands in each market. Many water brands were poor in their minerals and salts. Suggestions for improvement of the quality of bottled and municipal water are provided.
The present study aimed to explore the trace elements Iron and Manganese in the bottled and municipal water brands available at Mansoura City, Egypt and to elucidate whether these drinks are safe and potable. The levels of the two metals were determined by SensAA Atomic Absorption Spectrophotometer. Statistical analysis was conducted through SPSS Package (version 20). Except for Dasani, the mean values of Iron in all water types overpassed the standard levels set by the Egyptian Organization for Standardization and Quality (0.3 ppm), European Commission (0.2 ppm), World Health Organization (0.3 ppm) and Environmental Protection Agency (0.3 ppm). A similar trend was exhibited by Manganese in Aquafina, Dasani, Hayat, Siwa and municipal water that exceeded the standard levels (0.4, 0.05, 0.1 and 0.05 ppm, respectively). Manganese was detected at extremely high amounts in two Aquafina water samples. These findings highlight the importance of the regular maintenance, periodic examination and refinement of the storage and packaging processes of water. Both the bottled and municipal water consumed by millions of people at Mansoura require further purification to comply with the drinking water quality standards. Water bottling companies should adopt the vision of zero waste by using recycble and renewable, eco-friendly materials.
Quang Ninh is a coastal province of Northeast Vietnam, with the terrain and wetland ecosystems diversity. Wetland has an important role for livelihood of local communities, and biodiversity conservation, environmental protection and natural disaster prevention. However, currently in Quang Ninh wetland is facing many challenges in the exploitation of resources, and management practice. The pressures of population growth and socio-economic development activities are increasingly serious threat to the ecological services of wetlands in this region. The use of wetlands in the traditional ways revealed many shortcomings in the exploitation and use of natural resources, and wetland has not been strictly controlled. The question for wetland management in Quang Ninh is how to use wise use, both rational exploitation of resources in order to meet the livelihood of local people while maintaining the functions and ecosystem services of wetlands.\nBased on the field research on resources and the issues of wetland use; and the surveys on natural and the socio-economic conditions in Quang Ninh, this study aimed to find out the shortcomings in wetland use and management, and recommended solutions for wise use of wetlands based community approach and the principle of people-centered. \nThe proposed framework of wetland management and wise use based communities and principle of people-centered is implemented consisting of 7 different steps, including: zoning wetland ecosystems, identifying the importance of each area and ecosystem services, assessment of resource degradation and their causes, identifying priority goals, and implement of wise use of wetland.
This paper analyzes Moldova’s agri-food products competitiveness taking as main indicator the foreign trade activity. Thus, changes that occurred in commodities structure and their geographical distribution are examined. Also, comparative advantages and disadvantages are evaluated based on the Relative Trade Advantages (RTA) index in relation to CIS and EU countries. The study analyzes time series from the period 2001-2014 provided by the National Bureau of Statistics. The results show that Moldova still remains a net agri-food exporter, while total volume, worth and geographical distribution changed. Despite the fact that the value of both agri-food exports and imports increased during the investigated period, the growth rate of imports was higher than that of exports. The agri-food trade geographical distribution changed after 2006, increasing the share of EU and other countries. Beverages, edible fruits and nuts, cereals, oil seeds and oleaginous fruits, animal or vegetable fats and oils are the main agri-food exported products. Competitive advantages were found for aggregations as: dairy produce, edible vegetables, cereals, oil seeds, beverages. Disadvantages are characteristic for commodities as coffee, tea, fish and crustaceans etc. Some aggregations have switching values for the RTA index, which indicates the possible increase in competitiveness of certain products that can be developed in the future.
Farm tractors skidding is one method of timber extraction in forestry. The log skidding with farm tractors was analyzed and a new skid trail pattern designed. The study started describing current skidding operations with time study. Then, optimum skidding model was created with Linear Programing. The new skidding pattern was constituted by optimum skidding model equation and Geographical Information Systems analysis at the study area. At the end of the study the developed new skid trail pattern was tested on the study area and tested by time study. With the developed “directly skid trail pattern” model, a 16.84% increase in working time performance was observed when the products were extracted by farm tractors compared to the existing practice. Furthermore, the average soil compaction value measured in the study area at depths of 0-5 cm and 5-10 cm was found to be greater in the sample area skid trails than in the control points. The average density of skid trails opened under the same operation was 281 m/ha, while with the developed pattern, this was decreased to 187 m/ha. Therefore environmental damages were decreased.
In this article, we conducted an investigation using a mathematical model to verify if a long-term relationship exists between cardiological and neurological aspects with pulmonary hemodynamic signals during sleep, the methodology we applied in this paper is mainly based on four basic parts, in first part we applied unit root tests to assess the stationarity of the series, the second step is to apply the test of Co- integration model and quantify later this long-term relationship. Finally, we applied the Granger causality tests to the entire panel, which consists of the eighteen patients taken from MIT-BIH Polysomnographic database.\nThe results found in this study show how the long-term interaction between the Neuro Cardiopulmonary Hemodynamic signals, and reveal how the importance of understanding these interactions can help the doctor to understand the risks that may exist between these interactions during sleep. \nThe originality of this article is the number of variables incorporated in our model study. Unlike the majority of studies conducted with only two variables, our study is multidimensional. The main advantage of a multidimensional and multivariate model is to solve a multitude of problems, which is not the case in studies in two dimensions.
An efficient iterative method (WCIP) with auxiliary source, is used to analyze a recon?gurable filter with integrated lumped element. This technique is based on an iterative cross-functional approach in waves, using auxiliary sources located to model the active elements of the studied circuit. To validate this work, the results obtained are compared with those obtained by the iterative method using surface impedance and those obtained by the software HFSS\nKeywords: almost periodic circuits, auxiliary source iterative process, lumped element
Study of fabricating a symmetrical surface gratings on a UV polymer at submicron range using holographic interferometry and molding processes is developed. First, holographic interference using a 325 nm He-Cd laser was used to create the master of the periodic line structure on an i-line sub-micron positive photoresist film. Then, a nickel thin film was then sputtered onto the positive photoresist. Final line pattern on a UV polymer was formed from casting against the master mold. From experimental results show the technique can accurately control the grating distance and vertical depth. Average aspect ratios of grating distance to vertical depth are at the range from 1.55 to 2.58. Second, a traditional III-V GaAs/AlGaAs based semiconductor solar cell heterojunction structure is grown to investigate the surface polymer passivation effect on this kind of solar cell. For GaAs/AlGaAs solar cell, the top n-GaAs/n-AlGaAs structure is responsible for the selective etching stop layer. The selective etched surface barriers associated with polymer gratings with different aspect ratios are produced on solar cell surface by using the photolithography and Micro Electro Mechanical Systems (MEMS) techniques. Then, a reflective-type diffraction optical grating is fabricated on the surface of the solar cell to redirect the incident light reflected from the solar cell back onto the solar cell surface. The experimental results show that the addition of the surface optical gratings reduce the light reflectivity value as high as 25%. From inspection of surface reflectivity, the average reflectivity is found to be improved and decreased from 12.1% down to 7.9 %.
Postoperative cognitive function and recovery time from total intravenous anesthesia (TIVA) and volatile anesthetics have been compared in previous studies. We hypothesized that adding dexmedetomidine to TIVA would decrease the magnitude of postoperative cognitive dysfunction and lead to better hemodynamic stability. Methods: After approval of the Ethics Committee, 18 male and 22 female patients (age, 20–60-years) were divided randomly into two groups. All patients were administered the Mini Mental State Examination (MMSE) during the premedication visit and the scores were recorded. Propofol and remifentanil were infused in the operating room to induce anesthesia in both groups. A 0.5 µg/kg dexmedetomidine infusion was started in the dexmedetomidine group, with no loading dose, and no dose changes were made. After surgery, cognitive function was evaluated with the MMSE at 2 and 24 hours postoperatively and again 1 week and 1 month later. Results: A reduction in hemodynamic values was observed in both groups after induction of anesthesia. Patients receiving dexmedetomidine required less remifentanil (p < 0.05). Early recovery was detected by eye opening, squeezing fingers, and spontaneous breathing, and no differences were observed between the groups. No differences in the MMSE scores were detected at any of the time points between the groups. Conclusion: These results suggest that dexmedetomidine added to TIVA had no negative effects on postoperative recovery or cognitive function. \nKey words: dexmedetomidine, anesthesia, cognitive function
This study investigated the relationship between demographic variables and job satisfaction among social studies education academic staff of Colleges of Education in South East, Nigeria. Five research questions and five null hypotheses guided the study. The study employed correlational survey research design. Six hundred and thirty two respondents participated in the study. Correlates of academic staff Job Satisfaction Questionnaire (QASJSQ) developed by the researchers was the instrument for data collection. Data were analyzed using means, standard deviations and multiple linear regressions. The findings of the study among others showed that the levels of job satisfaction of academic staff were significantly related to their ranks and length of service while gender, age and marital status played no significant role in predicting job satisfaction among academic staff. Based on these findings, it was recommended; among others that the government and other important stakeholders should initiate policies and programmes that would take care of such demographic diversities in the workplace and enhance job satisfaction among academic staff of Colleges of Education in South East, Nigeria.
Type I diabetes is considered to be an autoimmune disorder which occurs when the immune system attacks the body’s own tissues and organs. In the present study, patients were divided into four groups according to their health state with five patients each. In addition to a normal group which represents healthy individuals. Blood samples were collected from each individual in the five groups to determine blood glucose, serum total bilirubin, direct bilirubin, albumin, total protein, ALT, AST, urea and uric acid were measured in each sample. The results showed that all biochemical parameters were around the normal levels. Whereas, the HLA-DQA1 exon2 gene of the four studied groups were mutated when compared to the normal and NCBI reference.
Purpose: We investigated the prognostic value of prognostic nutritional index (PNI) in locally-advanced rectal cancer (LARC) patients treated with neoadjuvant chemoradiotherapy (NCRT) followed by surgery.\nMethods: Seventy-four LARC patients received 50.4 Gy (1.8 Gy/fx) radiotherapy (RT) and concurrent 5-Fluorouracil-based chemotherapy. PNI was calculated by utilizing pre-NCRT blood data for each patient. The primary endpoint was the impact of PNI on overall survival (OS). Secondary endpoint was best PNI cut-off value for this patient population.\nResults: Median follow-up was 51 months. Median age was 56 years, 93.2% and 67.6% had T3-4 tumor and clinically involved lymph nodes, respectively. The median OS time was not reached during this analysis, and the 5- and 7-year OS estimates were 74.7% and 71.6%, respectively. A PNI cut-off value of 39.4 was identified by using receiver operating curve (ROC) analysis with high PNI (?39.4) patients being associated with significantly longer survival (p<0.0001) which also remained significant (p<0.0001) in multivariate analysis.\nConclusions: The simply calculated pre-NCRT PNI is a useful tool in prognostic stratification LARC patients treated with NCRT and surgery. Therefore, as an adjunct to other prognostic factors, we recommend the inclusion of PNI in routine pretreatment assessment of LARC patients planned to be treated curatively.
The objectives of this research were to estimate different nonlinear models for describing the growth curve of Lori-Bakhtiari sheep as to investigate the environmental effect on the growth curve parameters. The data set had been collected from Lori-Bakhtiari sheep breeding station during 1990 to 2014. The data set consisted of a total of 17605 body weight recorded quarterly of the birth to yearling from 3521 lambs. The Brody, Von Bertalanffy, Gompertz and logistic nonlinear models were fitted by Gauss-Newton method to weight-age data using procedure NLIN. The growth curve parameters were analyzed the using procedures GLM and CORR of SAS software. The Brody model was adequate to predicate the growth curve parameters and presented the best overall goodness of fit according to the higher R2, lower RMS, AIC and BIC. Lambing year, sex and type of birth significantly affected all growth curve parameters (A, B and k) in the Brody model. Males were heavier at mature weight (85.33 ± 0.35vs. 57.68 ± 0.27 kg) than females but they matured more slowly (0.0048 ± 0.0001 vs. 0.0064 ± 0.0000 kg/day). Phenotypic correlations between A and k was high and negative (-0.67), indicates that faster growing do not attain a large mature weight. It was concluded that the fitting of the Brody function can be suitable for Lori-Bakhtiari fat-tailed sheep in semi-migratory or village system conditions overall growth monitoring.
An inventory of insects has been made in these both sites where several methods of sampling were used (coloured and pheromone traps, branches’ sampling and olive gathering). Inventory highlights presence of 30 species whose 3 are undetermined which are divided in 15 orders and 26 families. Inventoried species have been divided in four groups: harmful predatory, useful and others. We have inventoried 10 dependent species to olive tree. The species distribution is analysed by ecological indices. As for fluctuations study of Bactrocera oleae’s in both sites (Sidi Naâmane and Tala Mokar), allows us to note existence of three generations in 2010 and only one generation in 2011 in both olive groves. We can say that activity of the fly is closely related to olive production and to weather conditions (temperature and hygrometry). Elsewhere, infestations of year 2010 are higher according to year 2011. The ones recorded in region of Tala Mokar were higher compared to Sidi-Naâmane. Usually, the beginning of fruits infestations on “Chemlal” variety is being made later, that means about 15 of September when olive begins to turn rosy notably at Sidi Naâmane and also the beginning of damages however small take place in September to be spread until November. While in Tala, infestation is taken place in October to decline completely in December. Infestations are too much higher in altitude (Tala-Mokar) than in plain (Sidi-Naâmane)\n\nKeys Words: Inventory, Ecological indiex. Bactrocera oleae, Fluctuation, infestations, insects, tala mokar, Sidi Naâmane.
The paper uncovers a number of objective contradictions in educational activities in Russian Higher Education System. The correlation of active and passive methods of teaching is analyzed. The role of the play activity in active methods of teaching is justified. The concept of “play” as applied to the process of teaching in higher professional education is stated. Three methods of playing activity are considered and the computer play method is treated as most versatile and efficient. The essence of the business play is being uncovered and a generalized model of the business play is presented. An idea of using the method of the business play in the higher professional education is set forth. A conclusion is made on the utility of more intensive introducing the method of the computer business play into the process of upgrading the higher education system in Russia.\nKey words: Active methods of teaching, method of computer business play, generalized model of computer business play.
This descriptive quantitative study aimed at exploring the implementation of policies in Jordanian universities as perceived by academic staff members. Data was collected from 590 academic staff members working in Jordanian universities through a self-administered questionnaire. After confirming the normality, validity and reliability of research instrument, further statistical analysis was carried out to test the questions and hypothesis (mean. standard deviation, t-test, Bivariate Pearson Correlation coefficient, and ANOVA). Findings showed there was a medium to high implementation for such policies at Jordanian universities. The result also showed a significant difference in the implementation according to the universities’ sector; private universities rated higher implementation of their policies than governmental ones. However, results revealed there were no significant differences concerning academic ranking or academic position of staff members regarding their perception for the implementation of universities’ policies. Finally, result revealed a strong significant relationship between universities’ policies variables. \nKey Words: Jordanian Universities, Middle East University (MEU), Universities’ Policies, Governance Board.
In the paper the concept of information position an information situation for a system or object is developing. Estimation methods for information situation and information position are described. The purpose of the paper is to formalize the estimation criteria and to verify them in practical example. The estimation formula is derived on the base of analysis of the information position. A distinction between internal and external positions of the system is shown. It is established that both information position and situation depends on information demands of the system. It is shown that the proposed formal methods can serve as a base of support for decision making. In the whole, the methods for information position and situation estimation can enhance the quality of managerial decisions