DIFFERENTIAL EFFECTIVENESS OF THINK-PAIR-SHARE PROGRAMMING STRATEGIES, CONVENTIONAL METHOD AND LEARNING STYLES ON THE PROGRAMMING ACHIEVEMENTS OF SECONDARY SCHOOL STUDENTS IN IJEBU EDUCATION DIVISION, OGUN STATE

This work examined the effects of the think-pair-share programming strategy on students’ achievement in programming. It also determined the moderating effect of learning styles on students’ achievement in programming. The study adopted a pretest-posttest-control group quasi-experimental research design. One hundred and twenty-two (122) students offering computer studies in senior secondary 2 from the two purposively selected public senior secondary schools in Ijebu Education Division of Ogun State constituted the sample. Computer Programming Achievement Test (CPAT, r = 0.760) and Learning Style Inventory (LSI, r= 0.83) were used for data collection.  Data obtained were analysed through inferential statistics of analysis of covariance (ANCOVA) using IBM SPSS Statistics 23. The finding indicated that the think-pair-share programming strategy significantly improved students’ achievement in the programming aspect of computer studies.  It was also found that learning style is not a strong factor in the learning of programming. The findings suggest that teachers should adopt the think-pair-share programming strategy in the teaching and learning of computer programming in senior secondary schools. It is therefore recommended that teacher education programme should include the strategy as one of the methods in the computer science methods courses to enable would-be teachers to master its nitty-gritty, since it worked in the senior secondary school. Also, the government and school authority should organize series of training through workshops and conferences to enable the teachers to acquire the skills to use the strategy.   &nbsp

Influence of dynamical analysis of laser power on titanium alloy with boron carbide (Ti6Al4V-B4C) metal matrix composites

Abstract: LMD process is a means of producing metal composites with the aid of laser beam and powder fusing together. In this research work, Ti6Al4V alloy is fused with 10 wt % of B4C in order to form metal matrix composites (MMCs), and using the Ytterbium Fibre Laser System powdered at 3000 W. The laser powers were varied between 800 W and 2400 W while all other supporting process parameters were kept constant. The deposited composites were characterized through the surfacing microstructure, microhardness and dry sliding wear. The microstructural properties of the deposited samples were profound with α-Ti, β-Ti and intermetallic phase of (α+β) of titanium alloy and boron carbide particles. The microhardness tests revealed that the composites deposited with a laser power of 2000 W exhibited the highest hardness value of HV 471. Furthermore characterisation revealed that the sample produced with the laser power of 800 W produced the lowest wear loss and wear rate of 35.2 x 10-3 mm3 and 6.42 x 10-4 mm3/Nm. However, this paper presents a detailed study on the LMD of Ti6Al4V-B4C composites in order to improve the material properties for surface engineering applications

Analysis of the influence of the laser power on the microstructure and properties of titanium alloy - reinforced boron carbide matrix composite (Ti6Al4V-B4C)

Abstract: Laser Metal Deposition (LMD) process is a means of producing metal composites with the aid of laser beam being ejected onto the substrate with the participating powder and fused together after solidification. In this research work, Ti6Al4V alloy is fused with 20 wt % of B4C in order to form metal matrix composites (MMCs). Using the Ytterbium Fibre Laser System powdered at 3000 W, the laser powers were varied between 800 W and 2400 W while all other supporting process parameters were kept constant. The deposited Ti6Al4V-B4C composites were characterized through the surfacing microstructure, microhardness and dry sliding wear. The microstructural properties of the deposited samples were profound with Widmanstätten structure of α-Ti, β-Ti and (α+β) Ti phases. The microhardness tests revealed that the composites deposited with a laser power of 2000 W exhibited the highest hardness value and standard deviation of HV 445 ± 61. Furthermore characterisation revealed that, the sample produced with the laser power of 800 W had the lowest wear loss and wear rate of 35.2 x 10-3 mm3 and 6.42 x 10-4 mm3/Nm. However, the motivation for this work is to improve the material properties of Ti6Al4V alloy for surface engineering applications

Study on microstructure and mechanical properties of 304 stainless steel joints by TIG-MIG hybrid welding

Abstract: Stainless steel is a family of Fe-based alloys having excellent resistance to corrosion, and as such has been used imperatively for kitchen utensils, transportation, building constructions and much more. This paper presents the work conducted on the material characterizations of a TIG-MIG hybrid welded joint of type 304 austenitic stainless steel. The welding processes were conducted in three phases. The phases of welding employed are MIG welding using a current of 170A, TIG welding using the current of 190A, and a hybrid TIG-MIG welding with currents of 190/170A respectively. The MIG, TIG, and hybrid TIG-MIG weldments were characterized with incomplete penetration, full penetration and excess penetration of weld. Intergranular austenite was created towards the transition zone and the HAZ. The thickness of the delta ferrite (δ-Fe) formed in the microstructures of the TIG weld is more than the thickness emerged in the microstructures of MIG weld and hybrid TIG-MIG welds. A TIG-MIG hybrid weld of specimen welded at the currents of 190/170A has the highest UTS value and percentage elongation of 397.72 MPa and 35.7 %. The TIG-MIG hybrid welding can be recommended for high-tech industrial applications such as nuclear, aircraft, food processing, and automobile industry

Age of Sexual Debut and Patterns of Sexual Behaviour in Two Local Government Areas in Southern Nigeria

The study examines the age of sexual debut and patterns of sexual behavior in Ugep, Cross River State, and Badeku and Olunloyo in Oyo State. A survey of households and individuals was conducted in the three communities; qualitative data were also collected through in-depth interviews and focus group discussion. The median age of first sex among never-married males and females were 17 years and 18 years respectively; more than one in five adolescents have had sex before age 16. Nevermarried males and females initiated sex earlier than ever-married, older respondents. That 14 percent of married men keep other sexual partners besides their wives is indicative of substantial extramarital relationship; also 12 percent of never-married male respondents with regular sex partners have other sexual partners. Condom use is fairly high, especially in sexual relations involving non-regular partners. The higher likelihood of alcohol use in sexual liaison with non-regular sex partners is suggestive of high prevalence of transactional sex and spontaneous or unplanned sex under the influence of alcohol, with their implications for the spread of HIV and AIDS. The study underscores the need for adolescent sexual and reproductive health education and behaviour change communication among all segments of the population and inculcation of values less favourable for the spreadof sexually transmitted infection.(Afr J Reprod Health 2012; 16[4]: 81-94)

Characterization of surface roughness of laser deposited Titanium alloy and copper using AFM

Abstract: Laser Metal Deposition (LMD) is the process of using the laser beam of a nozzle to produce a melt pool on a metal surface usually the substrate and metal powder is been deposited into it thereby creating a fusion bond with the substrate to form a new material layer against the force gravity. A good metal laminate is formed when the wettability between the dropping metal powder and the substrate adheres. This paper reports the surface roughness of laser deposited titanium alloy and copper (Ti6Al4V + Cu) using the Atomic Force Microscopy (AFM). This AFM is employed in order to sense the surface and produce different manipulated images using the micro-fabricated mechanical tip under a probe cartridge of high resolution. The process parameters employed during the deposition routine determines the output of the deposit. A careful attention is given to the laser deposited Ti6Al4V + Cu samples under the AFM probe because of their single tracked layers with semi-circular pattern of deposition

Caregiver food behaviours are associated with dietary intakes of children outside the child-care setting

OBJECTIVE: To evaluate whether food behaviours of parents are associated with children’s dietary intakes outside the child-care setting, and to compare children’s dietary intakes at home with foods and beverages consumed when they are at child-care centres. DESIGN: In 2005–2006, a survey was completed by parents of at least one child between 3 and 5 years old who attended group child-care centres. Surveys about nutrition practices were completed by centre directors. Research assistants observed foods and beverages consumed by children at lunchtime at the centres. SETTING: Sixteen licensed group child-care centres in three underserved New York City communities (South Bronx, East/Central Harlem, Central Brooklyn) and the Lower East Side of Manhattan. SUBJECTS: Two hundred parents. RESULTS: Children were more likely to consume healthful foods including fruits or vegetables if parents reported purchasing food from produce stands/farmers’ markets, shopped for frozen or canned fruits frequently and ate family meals or meals prepared at home daily. Children were more likely to consume less healthful foods such as French fries, or fruit drinks, more frequently if parents reported eating meals from fast-food or other restaurants at least once weekly, or if children ate while watching television. Types of foods and beverages offered to children at home (e.g. higher-fat milk, soft drinks and desserts) were less healthful than those offered at child-care centres. CONCLUSIONS: Children’s dietary intakes at home need to be improved. Parents need to understand the importance of providing home environments that support healthful food behaviours in children

Assessing Foods Offered to Children at Child-Care Centers Using the Healthy Eating Index-2005

The Healthy Eating Index-2005 (HEI-2005) has been applied primarily to assess the quality of individual-level diets, but was recently applied to environmental-level data. Currently, no studies have applied the HEI-2005 to foods offered in child-care settings. This cross-sectional study used the HEI-2005 to assess the quality of foods/beverages offered to preschool children (three-five years old) in child-care centers. Two days of dietary observations were conducted, and 120 children (six children per center) were observed, at 20 child-care centers in North Carolina between July 2005 and January 2006. Data were analyzed between July 2011 and January 2012 using t-tests. The mean total HEI-2005 score (59.12) was significantly (p<0.01) lower than the optimal score of 100, indicating the need to improve the quality of foods offered to children. All centers met the maximum score for milk. A majority also met the maximum scores for total fruit (17 of 20 centers), whole fruit (15 of 20 centers), and sodium (19 of 20 centers). Mean scores for total vegetable (mean=2.26±1.09), dark green/orange vegetables and legumes (mean=0.20±0.43), total grain (mean=1.09±1.25), whole grain (mean=1.29±1.65), oils (mean=0.44±0.25), and meat/beans (mean=0.44±0.25) were significantly (p<0.01) lower than the maximum scores recommended. Mean scores for saturated fat (mean=3.32±3.41; p<0.01), and calories from solid fats and added sugars (mean=14.76±4.08; p<0.01) suggest the need to decrease the provision of foods high in these components. These findings indicate the need to improve the quality of foods offered to children at the centers to ensure that foods provided contribute to children’s daily nutrition requirements