Combating overheating: mixed-mode conditioning for workplace comfort

ABSTRACT

Using post-occupancy evaluations of seven mixed-mode buildings – three in Australia and four in India – this paper demonstrates that effective mixed-mode conditioning (instead of year-round air-conditioning) can deliver comfortable workspaces. Occupant feedback reinforces strong associations between overheating, thermal comfort, overall comfort and perceived productivity. However, differing levels of thermal acceptability within and between the Australian and Indian contexts are evident. Occupants in the Indian buildings were found to tolerate a wider range of temperatures when compared with Western contexts where lower temperature limits entrench an energy demand through a greater reliance on air-conditioning. The outcomes from the study suggest that the perception of overheating and consequent risk to building performance can be intensified when occupants perceive limited adaptive opportunity or problems are not rectified quickly, whereas perceived control is less important where building systems are user responsive. Occupants in three of the study buildings also perceived higher-than-anticipated comfort which could be attributable to well-liked attributes, such as break-out spaces, daylight and fresh air included in these buildings. The findings challenge designers and clients to develop user-responsive climate interactive workplaces that capitalize on spatial and mixed-mode environmental control to tackle the question of overheating.     

The sexual harassment of men: Evidence for a broader theory of sexual harassment and sex discrimination.

The article imposes a social science framework on a law-based theory of sexual harassment forwarded by Katherine Franke (1997), which sought to address shortcomings of extant theory and to account for atypical forms of sexual harassment, notably male same-sex sexual harassment (SSSH). Sex-role spillover theory, sexual harassment climate theory, and Person × Situation theory are discussed with regard to their ability to account for SSSH. Preliminary postulates of this framework are tested with data from the 1995 Department of Defense sexual harassment survey of the U.S. military (J. E. Edwards, T. W. Elig, D. L. Edwards, & R. A. Riemer (1997). The results suggest that SSSH occurs because targeted men do not fit their offenders' gender-role stereotype of heterosexual hypermasculinity. Legal and workplace implications are discussed in an effort to expand existing theories and policies regarding sexual harassment to this more encompassing view. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Testing the effects of temperature and humidity on printed passive UHF RFID tags on paper substrate

This article is an interesting substrate material for environmental-friendly printable electronics. In this study, screen-printed RFID tags on paper substrate are examined. Their reliability was tested with low temperature, high temperature, slow temperature cycling, high temperature and high humidity and water dipping test. Environmental stresses affect the tag antenna impedance, losses and radiation characteristics due to their impact on the ink film and paper substrate. Low temperature, temperature cycling and high humidity did not have a radical effect on the measured parameters: threshold power, backscattered signal power or read range of the tags. However, the frequency response and the losses of the tags were slightly affected. Exposure to high temperature was found to even improve the tag performance due to the positive effect of high temperature on the ink film. The combined high humidity and high temperature had the most severe effect on the tag performance. The threshold power increased, backscattered power decreased and the read range was shortened. On the whole, the results showed that field use of these tags in high, low and changing temperature conditions and high humidity conditions is possible. Use of these tags in combined high-humidity and high-temperature conditions should be carefully considered.     

Medium chain triglycerides (MCT): State-of-the-art on chemistry,synthesis, health benefits and applications in food industry

Medium chain triglycerides (MCT) are esters of fatty acids with 6 to 12 carbon atom chains. Naturally, they occur in various sources; their composition and bioactivity are source and extraction process-linked. The molecular size of MCT oil permits unique metabolic pathways and energy production rates, making MCT oil a high-value functional food. This review details the common sources of MCT oil, presenting critical information on the various approaches for MCT oil extraction or synthesis. Apart from conventional techniques, non-thermal processing methods that show promising prospects are analyzed. The biological effects of MCT oil are summarized, and the range of need-driven modification approaches are elaborated. A section is devoted to highlighting the recent trends in the application of MCT oil for food, nutraceuticals, and allied applications. While much is debated about the role of MCT oil in human health and wellness, there is limited information on daily requirements, impact on specific population groups, and effects of long-term consumption. Nonetheless, several studies have been conducted and continue to identify the most effective methods for MCT oil extraction, processing, handling, and storage. A knowledge gap exists and future research must focus on technology packages for scalability and sustainability.     

Do properties of bioactive glasses exhibit mixed alkali behavior?

The effect of substituting K₂O for Na₂O on the physical and chemical properties of 15 glasses in the system Na₂O–K₂O–CaO–P₂O₅–SiO₂ was studied for three series: low (52 mol% SiO₂), medium (60 mol% SiO₂) and high (66 mol% SiO₂) silica. The SiO₂ content expressed as weight-% varied from 46 to 64 wt%, thus suggesting that the compositions were either bioactive or biocompatible. The crystallization tendency and sintering behavior were studied using differential thermal analysis and hot stage microscopy. Formation of silica- and hydroxy-apatite-rich layers were studied for glass plates immersed in static simulated body fluid. The release of inorganic ions into Tris buffer solution was analyzed using inductively coupled plasma optical emission spectrometer in dynamic and static conditions. Substitution of K₂O for Na₂O suggested mixed alkali effect (MAE) for the thermal properties with a minimum value around 25% substitution. With increased share of K₂O in total alkali oxides, the hot working window markedly expanded in each series. Silica and hydroxyapatite layers were seen only on the low silica glasses, while a thin silica-rich layer formed on the other glasses. In each series, greater dissolution of alkali and alkali earth ions was seen from K-rich glasses. Clear MAE and preferential ion dissolution were recorded for medium and high silica series, while for low silica glasses, the initial MAE dissolution trends become rapidly covered by other simultaneous surface reactions. MAE enables designing especially low silica bioactive glasses for improved hot working properties and medium and high silica glasses for controlled dissolution.     

Nanoscale Surface Characterization of Ceramic/Ceramic Coated Metallic Biomaterials Using Chromatic Length Aberration Technique

With the chromatic length aberration (CLA) technique, imaging of surfaces with complex three dimensional geometry is possible. Analysis of sample sizes in micro or nanometer scale is an added advantage available with CLA system. This article describes the methodology adopted for establishing the CLA technique for characterizing selected ceramic/ceramic coated substrates used in cardiovascular and orthopedic applications. The measurement of surface finish and coating thickness were validated against benchmarked technologies based on atomic force microscopy (AFM), stylus profilometry and standard ball cratering methods. Results of measurements were statistically analyzed by Student t test and reported the two tail p values to compare the results from different measurements techniques.     

Tailoring Terahertz Propagation by Phase and Amplitude Control in Metasurfaces

Metasurfaces have been very successful at demonstrating the ability to control the wave propagation over the broad electromagnetic spectrum in recent years. The output wavefronts can be controlled at will, by encoding specially designed abrupt changes of electromagnetic parameters into the metasurfaces, such as phase and amplitude. Constituted by a single- or few-layer of planar structures, metasurfaces are straightforward in design and fabrication, thus promising many credible applications. Moreover, such control concept can be further extended to the surface wave regime. In this review, we present our recent progress on metasurfaces capable of tailoring the propagation of both free-space and surface terahertz waves. Following an introduction of the basic concept and theory, a number of unique terahertz metasurfaces are presented, showing the ability to device ultra-thin and compact functional terahertz components.     

A Hybrid Artificial Intelligence Model for Skin Cancer Diagnosis

Melanoma or skin cancer is the most dangerous and deadliest disease. As the incidence and mortality rate of skin cancer increases worldwide, an automated skin cancer detection/classification system is required for early detection and prevention of skin cancer. In this study, a Hybrid Artificial Intelligence Model (HAIM) is designed for skin cancer classification. It uses diverse multi-directional representation systems for feature extraction and an efficient Exponentially Weighted and Heaped Multi-Layer Perceptron (EWHMLP) for the classification. Though the wavelet transform is a powerful tool for signal and image processing, it is unable to detect the intermediate dimensional structures of a medical image. Thus the proposed HAIM uses Curvelet (CurT), Contourlet (ConT) and Shearlet (SheT) transforms as feature extraction techniques. Though MLP is very flexible and well suitable for the classification problem, the learning of weights is a challenging task. Also, the optimization process does not converge, and the model may not be stable. To overcome these drawbacks, EWHMLP is developed. Results show that the combined qualities of each transform in a hybrid approach provides an accuracy of 98.33% in a multi-class approach on PH² database.     

Upper limb musculoskeletal disorders in healthcare personnel

The literature on upper limb musculoskeletal disorders (UL-MSD) in different groups of healthcare workers was reviewed: 65 relevant studies were collected. In dentists, the neck was the most frequently affected segment, with prevalences up to 73% and exceeding 50% in 7 out of 12 studies. In dental hygienists and in laboratory technicians, the hand/wrist had the highest prevalence in the majority of the studies. In nurses, the most seriously affected anatomic sites were the neck and shoulders. Physiotherapists had the lowest prevalence of UL-MSD. A high prevalence of upper limb disease, mainly carpal tunnel syndrome, was reported in dentists, dental hygienists, anesthesia nurses and endoscopists. The high prevalence of upper limb disorders/diseases reported in health personnel supports the hypothesis of a significant risk in these workers. However, the possible role of biomechanical overload, as much as that of stress or other personal factors, cannot be currently assessed.

Practitioner Summary: Published studies support the hypothesis of a significant risk of upper limb musculoskeletal disorders in healthcare activities. The neck was the most frequently affected segment in dentists, the hand/wrist in dental hygienists and in laboratory technicians, and the neck and shoulders in nurses. Lower prevalence was reported in physiotherapists. A high prevalence of carpal tunnel syndrome was also observed in various healthcare activities.