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The purpose of this paper is to evaluate the protective effects of Persian gum and gum Arabic on the survival of Lactobacillus plantarum subsp. plantarum PTCC 1896, Escherichia coli, Xanthomonas axonopodis, and Saccharomyces cerevisiae during freeze drying.

Cultures were harvested from the early stationary phase and enumerated after dilution according to the Milse Misra method. Bacterial suspensions were mixed with protective agents and frozen at –80°C before drying in a freeze dryer. Survival rates were determined both immediately during freeze drying and after 14 days of cold storage (at 4°C).

Compared to gum Arabic 5 and 10 percent (W/V) or skim milk 10 percent (W/V), Persian gum 1 percent (W/V) showed no significantly different effects on the survival of Lactobacillus plantarum subsp. plantarum PTCC 1896 (p<0.05). Similarly, no significant differences (p<0.05) were observed between Persian gum 6 percent (W/V), gum Arabic 6 percent (W/V), the combination of Persian gum 3 percent (W/V) and gum Arabic 3 percent (W/V), and skim milk 10 percent (W/V) in terms of their effects on the survival of Escherichia coli. Skim milk 10 percent (W/V) was, however, found to have significant (p<0.05) effects on the survival of Xanthomonas axonopodis and Saccharomyces cerevisiae. Statistically significant (p<0.05) effects were observed after 14 days of cold storage (4°C) by Persian gum 6 percent (W/V) on the survival of Escherichia coli and by gum Arabic 6 percent (W/V) on the survival of Xanthomonas axonopodis and Saccharomyces cerevisiae. It was concluded that protective agents could be replaced by Persian gum for its effect on the survival rate of Escherichia coli and by skim milk for its effects on the survival of Xanthomonas axonopodis and Saccharomyces cerevisiae. Persian gum 6 percent (W/V) seemed to be the best protective agent for Escherichia coli during 14 days of its storage as gum Arabic 6 percent (W/V) seemed to have the same performance for Xanthomonas axonopodis and Saccharomyces cerevisiae. Persian gum 1 percent (W/V) was also found an alternative protective agent for the freeze drying of Lactobacillus plantarum subsp. plantarum PTCC 1896.

As Iranian Persian gum is cheap due to its wide availability and seems to have effects similar to those of gum Arabic and skim milk at low concentrations, it may be considered a good candidate for industrial applications.

Personal protective clothing (PPC) enables people to work in hazardous environments, but PPC can have a detrimental effect on worker performance. Predicting garment effects on worker performance is difficult because quantitative relationships among garment properties and human responses are not known. Presents a systematic structure for studying the relationships among garment properties and their immediate effects on the worker. Using a survey of 118 studies, previous work was categorized according to garment parameters and dependent measures. Except for studies of heat stress, most of these studies compared competing garments or simply measured physiological response, rather than relating these effects to garment attributes. Such results are seldom transferable to other clothing systems or tasks. Proposes a conceptual model based on this systematic structure. Introduces garment impediment indices (GIIs) as response functions of garment attributes, and offers an approach for developing quantitative models of PPC effects on worker performance.

The purpose of this paper is to study the combined effects of moisture and radiation on thermal protective performance of protective clothing exposed to low level radiation.

Using a sweating manikin, the effect of radiation and moisture on heat and moisture transfer was initially analyzed under the dry manikin with sweating rate of 100 g/(m2h) exposed to 2.5 kW/m2, and then studied at 200 and 300 g/(m2h) exposed to 2 and 3 kW/m2, respectively. Finally, the combined effects of thermal radiation and moisture were predicted by fitting the relationships among heat loss and wet skin surface temperature, with the sweating rate and radiation intensity.

The results show that the heat loss and the wet skin surface temperature are affected by the combined effects of moisture and radiation, with two distinctly different trends. Heat loss from the manikin is increasing with the sweating rate, and decreasing with thermal radiation intensity. However, the wet skin surface temperature has an opposite situation.

Two filling equations are given to present the relationships among heat loss and wet skin surface temperature, with the sweating rate and radiation intensity. With these two equations, the heat loss and the wet skin surface temperature when exposed to radiation can be predicted by only measuring the mean radiant and ambient temperatures and controlling the sweating rate.

The purpose of this study is to determine the effect of ventilation openings and fire intensity on heat transfer and fluid flow within the microclimate between 3D human body and clothing.

On account of interaction effects of fire and ventilation openings on heat transfer process, a 3D transient computational fluid dynamics model considering the real shape of human body and clothing was developed. The model was validated by comparing heat flux history and distribution with experimental results. Heat transfer modes and fluid flow were investigated under three levels of fire intensity for the microclimate with ventilation openings and closures.

Temperature distribution on skin surface with open microclimate was heavily depended on the heat transfer through ventilation openings. Higher temperature for the clothing with confined microclimate was affected by the position and direction of flames injection. The presence of openings contributed to the greater velocity at forearms, shanks and around neck, which enhanced the convective heat transfer within microclimate. Thermal radiation was the dominant heat transfer mode within the microclimate for garment with closures. On the contrary, convective heat transfer within microclimate for clothing with openings cannot be neglected.

The findings provided fundamental supports for the ease and pattern design of the improved thermal protective systems, so as to realize the optimal thermal insulation of the microclimate on the garment level in the future.

The outcomes broaden the insights of results obtained from the mesoscale models. Different high skin temperature distribution and heat transfer modes caused by thermal environment and clothing structure provide basis for advanced thermal protective clothing design.

The purpose of this paper is to examine the extent to which negative online risk experiences (information breaches, explicit content exposure, cyberbullying and sexual solicitations) cause post-traumatic stress disorder (PTSD) symptoms in adolescents. The study also explores whether teens’ short-term coping responses serve to mitigate PTSD or, instead, act as a response to stress from online events.

The study utilized a web-based diary design over the course of two months. Data were analyzed using hierarchical linear modeling with repeated measures.

The study confirmed that explicit content exposure, cyberbullying and sexual solicitations (but not information breaches) evoke symptoms of PTSD. Analyses also indicated that teens engage in active and communicative coping after they experience post-traumatic stress, regardless of risk type or frequency.

The authors found that teens took active measures to cope with online risks soon after they felt threatened (within a week). Actively coping with stressful situations has been shown to enhance adolescent resilience and reduce long-term negative effects of risk exposure. If these early coping behaviors can be detected, social media platforms may be able to embed effective interventions to support healthy coping processes that can further protect teens against long-term harm from exposure to online risks.

This is the first study to examine situational PTSD symptoms related to four types of adolescent online risk exposure within the week exposure occurred. By applying two competing theoretical frameworks (the adolescent resilience framework and transactional theory of stress), the authors show empirical evidence that suggests short-term coping responses are likely a stress reaction to PTSD, not a protective factor against it.

This paper analyzes the measurement of effective protective rates when there is joint production. It shows that special attention is required when tradables are jointly produced with non‐tradables, and especially when there are significant changes in the prices of non‐tradables. Input‐output formulas for the Balassa and Corden methods are provided.

The prevalence, correlates (child behaviour problems and negative parenting) and determinants (risk and protective factors) of parental need for support were examined in a community sample of 177 mothers with a child aged 1.5‐3.5 years, in order to draw a profile of families that need parenting support. A substantial number of the mothers reported needing support (40% reported need for information, 10% reported family and social support needs). This need was related to child behaviour problems and to negative parenting. Maternal depression, difficult temperament of the child and negative life events, as well as total number of risk factors, significantly predicted the need for support. Satisfaction with support (but not number of support sources) acted as a protective factor.

U.S.S.R. Scale removal at high temperatures. In pickling steels for scale removal, acid solution is now largely used with additions of acid corrosion inhibitors, but this often proves ineffective at temperatures of 50°C. or higher. Some of the literature is surveyed. In the present work the use of the (Russian) ChM as an additive in the pickling baths for different marks of Russian steels is described (the steels are in the U1A class—tabulated analyses). The identity of this material is not disclosed. Figures are tabulated showing time of removal of scale at temperatures of 15 to 70° using 15% sulphuric, and this with either 4 g./1. of ChM or 0.5 g./1. of stannous sulphate. There appears to be little difference: at 15° time is 82 min. for acid alone and 84 to 86 min. for the others; at 70° it is 9 min. for acid alone and 8 min. with additive. Other figures show that the protective action of ChM sharply declines e.g. from 87% at 15° to 12% at 70°; whereas with a metal sulphate there is little change. Further experiments are described and discussed, and it is generally concluded that tin is the most effective inhibitor. A film of this at 70° and over is much more effective than ChM at 35°; the carbon content of the steel is less important; at the higher temperatures there is less risk of damage to steel articles; and it is easier to control time of treatment in pickling bath through practically complete cessation of hydrogen separation when scale removal is finished. Twelve references.—(B. S. Krasikov, etc., Jnl. Appl. Chem., 1957, (7), 993–997.)

This chapter introduces readers to a complex adaptive systems approach for integrating research on genes, behavior, and social structures/institutions. Until recently, scientists have resorted to reductionism as a decoding and epistemological strategy for understanding human health. The complex bonds among health’s biological, behavioral, and social dimensions, however, cannot be fully grasped with reductionist schemas. Moreover, because reducing and simplifying can lead to incomplete understanding of phenomena, the resulting deficient knowledge has the potential to be harmful.

To achieve its purpose, this primer will: (1) introduce fundamental notions from complexity science, useful for inquiry and practice integrating research on genes, behavior, and social structures; (2) outline selected methodological strategies employed in studying complex adaptive/dynamic systems; (3) address the question, “Specifically, how can a dynamic systems approach be helpful for integrating research on genes, behavior, and social structures/institutions, to improve the public’s health?”; and (4) provide examples of studies currently deploying a complexity perspective.

The originality/value of this primer rests in its critique of the research status quo and the proposition of an alternative lens for integrating genomic, biomedical, and sociological research to improve the public’s health. The topic of complex adaptive/dynamic systems has begun to flourish within sociology, medicine, and public health, but many researchers lack exposure to the topic’s basic notions and applications.