Paracompact and locally fine nearness frames

AbstractIn this article we define paracompact and locally fine nearness frames and show that they form (co)reflective subcategories of the category of nearness frames

Do Frictions Matter in the Labor Market? Accessions, Separations and Minimum Wage Effects

We measure labor market frictions using a strategy that bridges design-based and structural approaches: estimating an equilibrium search model using reduced-form minimum wage elasticities identified from border discontinuities and fitted with Bayesian and LIML methods. We begin by providing the first test of U.S. minimum wage effects on labor market flows and find negative effects on employment flows, but not levels. Separations and accessions fall among restaurants and teens, especially those with low tenure. Our estimated parameters of a search model with wage posting and heterogeneous workers and firms imply that frictions help explain minimum wage effects.minimum wage, labor market flows, monopsony, Bayesian estimation

Pointfree pseudocompactness revisited

We give several internal and external characterizations of pseudocompactness in frames which extend (and transcend) analogous characterizations in topological spaces. In the case of internal characterizations we do not make reference (explicitly or implicitly) to the reals

A few points on Pointfree pseudocompactness

We present several characterizations of completely regular pseudocompact frames. The first is an extension to frames of characterizations of completely regular pseudocompact spaces given by Väänänen. We follow with an embedding-type characterization stating that a completely regular frame is pseudocompact if and only if it is a P-quotient of its Stone-Čech compactification. We then give a characterization in terms of ideals in the cozero parts of the frames concerned. This characterization seems to be new and its spatial counterpart does not seem to have been observed before. We also define relatively pseudocompact quotients, and show that a necessary and sufficient condition for a completely regular frame to be pseudocompact is that it be relatively pseudocompact in its Hewitt realcompactification. Consequently a proof of a result of Banaschewski and Gilmour that a completely regular frame is pseudocompact if and only if its Hewitt realcompactification is compact, is presented without the invocation of the Boolean Ultrafilter Theorem

Comment on: `Pipe Network Model for Scaling of Dynamic Interfaces in Porous Media'

We argue that a proposed exponent identity [Phys. Rev. Lett 85, 1238 (2000)] for interface roughening in spontaneous imbibition is wrong. It rests on the assumption that the fluctuations are controlled by a single time scale, but liquid conservation imposes two distinct time scales.Comment: 1 page, to appear in Phys. Rev. Let

Direct hemoglobin measurement by monolithically integrated optical beam guidance

We present a concept for optical beam guidance by total internal reflection (TIR) at V-grooves as retro reflectors which are monolithically integrated on a microfluidic "lab-on-a-disk". This way, the optical path length through a measurement chamber and thus the sensitivity of colorimetric assays is massively enhanced compared to direct (perpendicular) beam incidence. With this rugged optical concept, we determine the concentration of hemoglobin (Hb) in human whole blood. Outstanding features are a high degree of linearity (R2 = 0.993) between the optical signal and the Hb together with a reproducibility of CV= 2.9 %, and a time-to-result of 100 seconds, only

The opportunities and challenges of digitalization for SME's

Small and Medium-sized Enterprises (SME's) are prevalent in the South African Industry and have been globally recognized for their contributions to economic development, job creation, poverty alleviation, and innovation. Although SME's are aware and can benefit significantly from digital systems, the time, skills, and finances required to develop SME-specific systems are prohibitive. This is because the ability to define sensor to enterprise systems demands for SME's is dependent on specific needs. The current solutions that are offered to SME's are stand-alone and not integrated. This research provides insights into the engagement and development of a demand-driven SME ecosystem. The research provides insights into the digital system priorities of some 200 South African SME's. Based on the analysis of the survey conducted, the researchers designed and developed the initial four systems for SME's out of the 10 identified. This paper covers the data gathering, design, and delivery phase of the 4 functions

Assessing accessibility and availability of portable water supply in selected communities of Lepelle-Nkumpi local municipality, Limpopo province of South Africa

In this study, we assessed the accessibility and availability of portable water supply in selected communities of the Lepelle-Nkumpi Local Municipality. A systematic random sampling method was used to select 49 households from Mashite village and 77 households from Lebowakgomo Zone F. A Global Positioning System (GPS) was used to collect absolute locations of available water taps and the reservoir in the Mashite village whereas for Lebowakgomo Zone F municipal household taps data were recorded. Data were statistically analysed and the Pearson Chi-Square test was used to test the relationship between the reuse of onsite greywater at Mashite rural area and Lebowakgomo township area. The results showed that the majority of households (38%) in Mashite village obtained their water from the rivers whereas all respondents in Lebowakgomo Zone F had access to tap water. Further, ninety-four percent (94%) of respondents in Mashite village travel less than 1 km to a water source, while 6% travel between 1 and 3 kms. Proximity to standard water pipes in Mashite village was beyond the recommended 200 m distance. Thirty-five percent (35%) of the respondents in Mashite village and 77% respondents in Lebowakgomo Zone F, respectively, indicated that the available water met their water needs although the quantity of water used per month differed between the two areas. Most of the respondents (56%) in Mashite village used 250 L of water per month while 61% use more than 6000 L in Lebowakgomo Zone F. It is, therefore, recommended that local municipalities should provide rural communities with water taps that are in close proximity of 200 m to households as recommended by the Department of Provincial and Local Government (DPLG). However, even though the DPLG recommends the proximity level of 200 m, this is still questionable as some households still struggle to have enough running water as these taps are sometimes vandalised, not functional or even situated in elevated areas were it becomes impossible for water to ascend uphill due to the pressure of the water. In addition, it is further recommend that local authorities provide household taps that are functional. Moreover, the service delivery should be improved, and water provision infrastructure maintained regularly

Consumers’ views and use of labels on food items sold in Bulawayo urban province, Zimbabwe

Food labels are a medium by which consumers acquire knowledge about packaged foods they are considering to purchase. The label makes the first impression about a product and has a great effect on the purchasing decision for consumers. In recent years, literate consumers have become interested in nutritional issues. Lifestyle, age, dietary and safety concerns have been the contributing factors to nutritional awareness by consumers. Nutritional labels can generally have a positive impact on food consumption and may save health-care costs for those consumers with health concerns. On the other hand, for those consumers who are illiterate, price may be more important in making purchase decisions. This study intended to investigate how consumers in Bulawayo Urban Province (Zimbabwe) view and use labels on packaged food items. Seventy-five randomly selected consumers were questioned about their perceptions, attitudes and use of label information using open ended structured questionnaires. The consumers were selected on the basis of being present at the supermarkets at the time of sampling. The respondents were interviewed at different times of the day to cater for employed and unemployed people. The results obtained indicate that the extent to which food labels are used depends on factors such as price of food products, individual health needs and gender. For consumers who use food labels to make their purchase decisions, not all the information on the label is considered. Items on the labels to which the consumers responded were brand, nutritional profile and mass of product in relation to the price. The label elements which were extensively used by consumers in this study are date mark (81.3%), weight of food (89.3%) and price (77.3%). The least used element is the nutritional panel (50.7%). About 44% of the consumers were not sure about the trustworthiness of the information given on food labels. Food labels are important to a greater extent for people with special dietary requirements, while the remainder of the studied population are influenced by price in their purchase decisions. Consumers seem not to understand some of the information on the food labels because of the difficulties in interpreting what is written.Keywords: Consumer, packaged food, labels, nutrition, nutritional panel, perceptions, purchase, behaviou