The role of particle size on bio-fouling properties of oil-impregnated nano-porous silica coatings

The growth of algae, barnacles, moulds and other organisms on ship hulls, concretes, painted or coated surfaces, especially in the tropics, could be harmful and aesthetically unattractive. Control of such growths usually includes the use of coatings that may contain chemicals that can destroy these organisms, and in some cases, other lives. However, manipulation of the topography of material surfaces in the so called Slippery Liquid Infused Porous Surfaces (SLIPS) seems to be excellent safety approach of tackling bio-fouling problems. In this work, we have fabricated hydrophobic silica coatings of different particle sizes, ranging from 10 nm to 700 nm; the coatings have been impregnated with non-volatile oil (squalane) to obtain artificial rims of Nepenthes Pitcher plant. Wettability and anti-biofouling tests carried out on the fabricated coatings using water drops and algal cell media have shown that surfaces coated with the smallest nano-sized particles (10 nm) possess better stability and anti-biofouling characteristics toward algae adhesion.Keywords: Nano-particles, Porous coating, oil-impregnation, bio-fouling, wettabilit

Generation Gap and the Impact of the Web on Goods Quality Perceptions

This study explores how age and general online shopping experience affect consumer perceptions on product quality uncertainty. Using the survey data collected from 549 consumers, we investigated how they perceive the uncertainty of product quality on six search, experience and credence goods. The ANOVA results show that age and the Web shopping experience of consumers are significant factors. A generation gap is indeed seen for all but one experience good. Web shopping experience is not a significant factor for search goods but is for experience and credence goods. There is an interaction effect between age and Web shopping experience for one credence good. Implications of these results are discussed

The effect of autonomy, training opportunities, age and salaries on job satisfaction in the South East Asian retail petroleum industry

South East Asian petroleum retailers are under considerable pressure to improve service quality by reducing turnover. An empirical methodology from this industry determined the extent to which job characteristics, training opportunities, age and salary influenced the level of job satisfaction, an indicator of turnover. Responses are reported on a random sample of 165 site employees (a 68% response rate) of a Singaporean retail petroleum firm. A restricted multivariate regression model of autonomy and training opportunities explained the majority (35.4%) of the variability of job satisfaction. Age did not moderate these relationships, except for employees >21 years of age, who reported enhanced job satisfaction with additional salary. Human Capital theory, Life Cycle theory and Job Enrichment theory are invoked and explored in the context of these findings in the South East Asian retail petroleum industry. In the South East Asian retail petroleum industry, jobs providing employees with the opportunity to undertake a variety of tasks that enhanced the experienced meaningfulness of work are likely to promote job satisfaction, reduce turnover and increase the quality of service

Smallholder dairy systems in the Kenya highlands: breed preferences and breeding practices

A stratified random sample, cross-sectional survey of 1755 households in the Kenya highlands was conducted between June 1996 and April 1998 to evaluate the rationale underlying smallholders’ breeding decisions. Additional data were collected in a follow-up survey of 50 households sub-sampled from the main survey sample. Cattle-keeping households were 987, of which 62% kept Friesian (FR) and Ayrshire (AY), 22% kept East African Zebu, Boran and Sahiwal (ZB) cattle and 16% kept Guernsey and Jersey (GJ) breeds. Farmers keeping ZB and GJ ranked producing milk for family consumption the most important reason for keeping cattle, whereas those keeping FR and AY ranked producing milk for cash income most highly. Farmers’ relative preference for GJ, AY and FR for high milk yield over hardiness was respectively 3.46, 7.58 and 17.63 times more when compared with preference for ZB. Additional attributes rated highly in the Bos taurus breeds were high butterfat yields, heavier bodyweight, unselective feeding behaviour in zero-grazing systems, hardiness and disease resistance in semi-zero- and free-grazing systems and high market value. Breeding practices tended to favour the use of dairy breeds of larger body size, particularly Friesian, which is inconsistent with technical recommendations that favour the use of the smaller dairy cattle breeds. These findings suggest that multiple objectives, including the need for more milk, adaptability to local feed conditions and diseases, and the provision of non-market production such as manure, insurance and financing roles of cattle, underlie smallholders’ breeding decisions in the Kenya highlands

Smallholder dairy systems in the Kenya highlands: breed preferences and breeding practices

A stratified random sample, cross-sectional survey of 1755 households in the Kenya highlands was conducted between June 1996 and April 1998 to evaluate the rationale underlying smallholders’ breeding decisions. Additional data were collected in a follow-up survey of 50 households sub-sampled from the main survey sample. Cattle-keeping households were 987, of which 62% kept Friesian (FR) and Ayrshire (AY), 22% kept East African Zebu, Boran and Sahiwal (ZB) cattle and 16% kept Guernsey and Jersey (GJ) breeds. Farmers keeping ZB and GJ ranked producing milk for family consumption the most important reason for keeping cattle, whereas those keeping FR and AY ranked producing milk for cash income most highly. Farmers’ relative preference for GJ, AY and FR for high milk yield over hardiness was respectively 3.46, 7.58 and 17.63 times more when compared with preference for ZB. Additional attributes rated highly in the Bos taurus breeds were high butterfat yields, heavier bodyweight, unselective feeding behaviour in zero-grazing systems, hardiness and disease resistance in semi-zero- and free-grazing systems and high market value. Breeding practices tended to favour the use of dairy breeds of larger body size, particularly Friesian, which is inconsistent with technical recommendations that favour the use of the smaller dairy cattle breeds. These findings suggest that multiple objectives, including the need for more milk, adaptability to local feed conditions and diseases, and the provision of non-market production such as manure, insurance and financing roles of cattle, underlie smallholders’ breeding decisions in the Kenya highlands

Smallholder dairy systems in the Kenya highlands: cattle population dynamics under increasing intensification

A cross-sectional stratified random sample survey of 1755 households in the Kenya highlands was conducted between June 1996 and April 1998 to quantify cattle population dynamics in smallholder herds. The free-, semi-zero- and zero-grazing systems practised represented increasing levels of intensification of the farms. Additional data were collected in a follow-up survey of 50 households from the main survey sample. In the main survey there were 987 cattle-keeping households, of which 44, 33 and 23% practised zero-, semi-zero- and free-grazing systems, respectively. Compared to free-grazing, zero-grazing farms had a higher proportion of cows in the herd (0.62 vs. 0.51) but lower calving rates (0.52 vs. 0.69), higher losses of potential heifer replacements (0.47 vs. 0.38), fewer heifer replacements as a proportion of cows disposed (0.46 vs. 1.11) and shorter productive life (3.8 vs. 4.8 years). Semi-zero-grazing farms had intermediate performance. They and the zero-grazing farms were unable to maintain their herds without acquiring replacements externally. Animal class mortality rates were high (7–19%) regardless of grazing system practised. Diseases accounted for the largest proportion of animal exits: 85% of heifer-calves, 38% of heifers and 36% of cows. According to farmers’ ranking, East Coast fever and Anaplasmosis diseases assumed less importance with a shift from free-grazing to zero-grazing system. A household’s needs for cash was the second most frequent reason after disease for animal exits: 33% of heifers and 27% of cows, indicating the importance of cattle as liquid capital assets. The results showed that many zero-grazed herds required external sources of replacement animals to sustain their populations. Solutions to this constraint will include technical and institutional innovations to serve small-scale farms that may result in greater complementarities between the small- and large-scale production components of the dairy sub-sector

Smallholder dairy systems in the Kenya highlands: cattle population dynamics under increasing intensification

A cross-sectional stratified random sample survey of 1755 households in the Kenya highlands was conducted between June 1996 and April 1998 to quantify cattle population dynamics in smallholder herds. The free-, semi-zero- and zero-grazing systems practised represented increasing levels of intensification of the farms. Additional data were collected in a follow-up survey of 50 households from the main survey sample. In the main survey there were 987 cattle-keeping households, of which 44, 33 and 23% practised zero-, semi-zero- and free-grazing systems, respectively. Compared to free-grazing, zero-grazing farms had a higher proportion of cows in the herd (0.62 vs. 0.51) but lower calving rates (0.52 vs. 0.69), higher losses of potential heifer replacements (0.47 vs. 0.38), fewer heifer replacements as a proportion of cows disposed (0.46 vs. 1.11) and shorter productive life (3.8 vs. 4.8 years). Semi-zero-grazing farms had intermediate performance. They and the zero-grazing farms were unable to maintain their herds without acquiring replacements externally. Animal class mortality rates were high (7-19%) regardless of grazing system practised. Diseases accounted for the largest proportion of animal exits: 85% of heifer-calves, 38% of heifers and 36% of cows. According to farmers' ranking, East Coast fever and Anaplasmosis diseases assumed less importance with a shift from free-grazing to zero-grazing system. A household's needs for cash was the second most frequent reason after disease for animal exits: 33% of heifers and 27% of cows, indicating the importance of cattle as liquid capital assets. The results showed that many zero-grazed herds required external sources of replacement animals to sustain their populations. Solutions to this constraint will include technical and institutional innovations to serve small-scale farms that may result in greater complementarities between, the small- and large-scale production components of the dairy sub-sector. (C) 2003 Elsevier B.V. All rights reserved

Borderline surgery of invasive kidney tumours

Treatment of hypernephroma presenting with atria-caval involvement without distant metastases is a surgical challenge. The procedures used in three different cases are described. In one case the caval thrombus extending into the atria-caval junction was delivered during clamping of the atrium without cardiovascular bypass. In another case the remaining atrial thrombus was removed in a second session with cardiovascular bypass. For the third case cardiac bypass was established immediately to permit safe and complete removal of the atria-caval thrombus. In order to plan the surgical procedure adequately, it appears essential to determine exactly the upper level of the thrombus. In cases with atrial involvement, cardiovascular bypass is advisable to perform radical surgery under the safest conditions. © 1984 Springer-Verlag.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Order processing cost reduction in a joint vendor-buyer inventory system via the application of information technology

[[abstract]]Modem information technologies have become important means for manufacturing and retailing firms to gain such competitive advantages as lower logistics costs and securer customers' loyalty. In this paper, we investigate a joint inventory system where the vendor produces a single item for its sole buyer and the buyer sells the item to consumers with backorders allowed. Each production lot is delivered to the buyer in a number of shipments and consecutive shipments will be increased by a fixed factor. Both vendor and buyer are willing to participate in order processing time reduction by applying information technologies in order to decrease their joint total cost. The order processing time can be reduced by certain expenditures and will affect the lot-size decisions. An analytical model is developed for determining the optimal expenditure in order processing time reduction and lot sizes for both vendor and buyer. The numerical experiment along with sensitivity analysis is also performed to obtain some insights of our model.[[notice]]補正完