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The design of the Advanced Combat Helmet (ACH) currently in use was optimized by its designers in order to attain maximum protection against ballistic impacts (fragments, shrapnel, etc.) and hard-surface/head collisions. Since traumatic brain injury experienced by a significant fraction of the soldiers returning from the recent conflicts is associated with their exposure to blast, the ACH should be redesigned in order to provide the necessary level of protection against blast loads. The paper aims to discuss this issue.

In the present work, an augmentation of the ACH for improved blast protection is considered. This augmentation includes the use of a polyurea (a nano-segregated elastomeric copolymer) based ACH external coating. To demonstrate the efficacy of this approach, blast experiments are carried out on instrumented head-mannequins (without protection, protected using a standard ACH, and protected using an ACH augmented by a polyurea explosive-resistant coating (ERC)). These experimental efforts are complemented with the appropriate combined Eulerian/Lagrangian transient non-linear dynamics computational fluid/solid interaction finite-element analysis.

The results obtained clearly demonstrated that the use of an ERC on an ACH affects (generally in a beneficial way) head-mannequin dynamic loading and kinematic response as quantified by the intracranial pressure, impulse, acceleration and jolt.

To the authors’ knowledge, the present work is the first reported combined experimental/computational study of the blast-protection efficacy and the mild traumatic brain-injury mitigation potential of polyurea when used as an external coating on a helmet.

The coast at Berakas in the Brunei-Muara district of Brunei Darussalam suffers from erosion caused by a combination of fluvial and marine processes. This paper investigates the rate and pattern of erosion along a 1.8-km stretch of coast to compare the difference between the unprotected and protected sections. We used (i) image and spatial analysis and (ii) field geomorphology. The Digital Shoreline Analysis System (DSAS) in ArcGIS was used to compare the study area using two Google Earth images. The study found that the unprotected section had receded by 4.6 m between 2009 and 2019, while the protected section had advanced by 8.0 m over the same period; intense gullying and slumping of cliff continued at both sections. The detached headland breakwaters in the protected section were effective in stabilizing the coast. A concrete drain installed parallel to the cliff edge appears to be capable of intercepting storm runoff, but its effectiveness was undermined by lack of maintenance. We conclude that terrestrial-fluvial processes continue to erode coastal land and cause slumping of the cliff face at Berakas. However, coastal protection structures that curb the marine process could stabilize the coastline, even where sediment transport is active.

Previous studies have shown a link between mental health functioning and involvement in HIV risk practices. The present research examines how well one specific group of men who have sex with other men (MSM) fare in terms of their mental health functioning, and then focuses on how mental health functioning relates to HIV risk practices in this population. The study was based on a national random sample of 332 MSM who use the Internet to seek men with whom they can engage in unprotected sex. Data collection was conducted via telephone interviews between January 2008 and May 2009. Depression is more common among men in this population than in the adult male population-at-large. All other measures of mental health functioning that were examined (self-esteem, impulsivity, current life satisfaction, optimism about the future) indicated low rates of mental health problem. Contrary to expectations, in nearly all instances, mental health functioning was not related to HIV risk practices.

More work needs to be done to understand the causes of depression among these men, and to assess how, if at all, depression relates to risk practices in this population. These findings suggest that factors other than mental health problems must be considered if one wishes to understand HIV risk taking in this population.

The purpose of this paper is to optimize the design of the advanced combat helmet (ACH) currently in use, by its designers in order to attain maximum protection against ballistic impacts (fragments, shrapnel, etc.) and hard-surface/head collisions. Since traumatic brain injury experienced by a significant fraction of the soldiers returning from the recent conflicts is associated with their exposure to blast, the ACH should be redesigned in order to provide the necessary level of protection against blast loads. In the present work, augmentations of the ACH for improved blast protections are considered. These augmentations include the use of a polyurea (a nano-segregated elastomeric copolymer)-based ACH external coating/internal lining.

To demonstrate the efficacy of this approach, instrumented (unprotected, standard-ACH-protected, and augmented-ACH-protected) head-mannequin blast experiments are carried out. These experimental efforts are complemented with the appropriate combined Eulerian/Lagrangian transient non-linear dynamics computational fluid/solid interaction analysis.

The results obtained indicated that: when the extent of peak over-pressure reduction is used as a measure of the blast-mitigation effectiveness, polyurea-based augmentations do not noticeably improve, and sometimes slightly worsen, the performance of the standard ACH; when the extent of specific impulse reduction is used as a measure of the blast-mitigation effectiveness, application of the polyurea external coating to the standard ACH improves the blast-mitigation effectiveness of the helmet, particularly at shorter values of the charge-detonation standoff distance (SOD). At longer SODs, the effects of the polyurea-based ACH augmentations on the blast-mitigation efficacy of the standard ACH are inconclusive; and the use of the standard ACH significantly lowers the accelerations experienced by the skull and the intracranial matter. As far as the polyurea-based augmentations are concerned, only the internal lining at shorter SODs appears to yield additional reductions in the head accelerations.

To the authors’ knowledge, the present work contains the first report of a combined experimental/computational study addressing the problem of blast-mitigation by polyurea-based augmentation of ACH.

To investigate how parental divorce and gender might influence the likelihood of engaging in a friends with benefits relationship (FWBR), and the likelihood of binge drinking and unprotected sex practices.

Using self-report measures, 99 undergraduates shared their parental marital history, experiences with FWBRs, and health risk behaviors.

Men, as compared with women, reported significantly more FWBRs as did participants with divorced/separated parents, as compared with those with married parents. Participants who had engaged in an FWBR reported significantly more binge drinking than those with no prior FWBR experience; however, no differences were found for gender or parental marital status. No significant differences emerged regarding the prevalence of unprotected sex.

The current study employed the use of self-report surveys, which can be subject to social desirability. All participants were recruited from a single liberal arts college with a limited sample of men with divorced or separated parents.

Using mixed methods (qualitative and quantitative) to explore young adults’ predictors and outcomes of engaging in FWBRs provided unique insights into how gender and parental relationships influence both casual sex and health-related behaviors.

The purpose of this paper is to overview the current state of affairs of the Indian heritage treasures, which are being identified, restored, preserved and promoted by various organizations at national and international levels with an emphasis on its documentation aspect. Lack of information about the heritage sites, structures and its significance, especially unprotected and unidentified, leads to its permanent loss. One of the prominent measures to safeguard from such irrevocable cultural deprivation is its documentation. Further, the study aims to examine the significant challenges associated with identifying unrevealed heritage assets of the country in the context of its preservation, documentation and promotion. As a suggestive measure, the study aims to propose the need for developing a comprehensive cultural heritage register assisted with technological aids focusing on community participation in taking stock of the heritage items they possess and enable them to effectively document.

The present study extracts the cultural heritage data available with the UNESCO belongs to Indian heritage assets inscribed in its World Heritage portal. The collected data has been analyzed and interpreted to overview the country's recognition at the global level. The data collected from the official portal is further explored and customized to have a lucid account. The details about the organizations and institutions working on heritage conservation and preservation activities in India are also collected. A review of published literature on the related areas has also been performed to identify the issues and challenges associated with the documentation of heritage assets to support this study. The study also included the researcher’s experience in working with cultural heritage documentation.

India holds a substantial quantity of cultural as well as natural heritage items. However, an exhaustive effort to document them at the national level is not being accomplished to its full potential. Many of the assets, inheritances or sites of cultural importance have not been fully identified, preserved or documented; hence, it is unrecalled forever once lost. Some organizations and individuals working on cultural heritage lack clarity in its function and do not follow any common standards in its documentation. For any conservation activity, documentation is prime, and the local community's support is also essential. Means of international collaboration for managing and promoting the heritage are required to be encouraged. Findings of the study demand the need for utilizing digital technologies to assist the documentation process. It emphasizes the requirement of having a web-based single window online gateway where an individual or community can dispense the knowledge and resources they possess hence contributing to heritage conservation, preservation and sustainability.

The study limited to Indian scenario and the data on the heritage sites are collected from UNESCO's World Heritage portal. Only the documentation and promotional aspects of the cultural heritage are discussed. There are many lesser-known and unprotected cultural heritage in different parts of the country with artistic value. The unique characteristics that have not been recorded anywhere are to be documented systematically to reduce the frequency and severity of losses. The implication of the study highlights the present scenario of cultural heritage documentation in India and the need for a comprehensive heritage information gateway supported with a register facility to precisely document and retrieve.

Aspects of culture which are inherited from the past to the present are to be preserved for future generations. Digital archives of cultural heritage and the use of digital tools to document them are effective mechanisms to protect and store the data on endangered heritage items. For any such conservation effort, documentation is its first step. Developing and facilitating access to an exclusive database of cultural heritage at risk boast its sustainability and can be enriched by the involvement of local communities. Public access to such a database would greatly support administrators, tourist departments, culture departments, development administration and conservation activists to gather the details of unprotected heritage items of the country, its present condition, risk of damage, etc. which further helps in its preservation, conservation, sustainability and promotion in a constructive manner.

To the authors' best knowledge, no such single and comprehensive mechanism in the country allow the individuals to contribute to the inventory list holding information about the identified, unprotected and unidentified heritage assets which are having a risk of damage, threat, decay, vulnerable, neglect, lack of use or inappropriate maintenance and development. Developing such a system with technological and data infrastructure helps to pool all the cultural heritage resources under one umbrella. It imparts the value and significance of protecting and promoting heritage inheritances and a safe haven of them from the risk of its chronic loss. The system can also support all the activities related to heritage protection and bring the local community to timely support and initiate such heritage conservation activities.

This paper aims to investigate the fire performance of composite beams when considering the hogging moment resistance of the fin-plate beam-to-girder joints including the effect of continuity of reinforcements.

Experiments on composite beams with fin-plate joints protected only at the beam ends are conducted. The test parameter is the specification of reinforcement, which affects the rotational restraint of the beam ends. In addition, a simple method for predicting the failure time of the beam using an evaluation model based on the bending moment resistance of the beam considering the hogging moment resistance of the fin-plate joint and the reinforcement is also presented.

The test results indicate that the failure time of the beam is extended by the hogging moment resistance of the joints. This is particularly noticeable when using a reinforcing bar with a large plastic deformation capability. The predicted failure times based on the evaluation method corresponded well with the test results.

Recent studies have proposed large deformation analysis methods using FEM that can be used for fire-resistant design of beams including joints, but these cannot always be applicable in practice due to the cost and its complexity. Our method can consider the hogging moment resistance of the joint and the temperature distribution in the axial direction using a simple method without requirement of FEM.

This paper aims to facilitate verification of computer modelling techniques for complex structures exposed to fire and to test the effect of some steel beams being left unprotected.

This paper describes a fire test conducted on a large-scale structure representing four corner bays of a typical multi-storey steel-frame office building.

A new and unexpected mode of damage occurred.

The test results indicate that an alternate reinforcement detail should be used in combination with unprotected beams.

The optimum design is applied to cost minimization of two types of welded steel structures in fire. Both unprotected and protected structures are investigated. The compressed rod of welded square box cross-section is designed to overall and local buckling. The bent beam of welded box section should fulfil the stress, deflection and local buckling constraints. The cost function consists of the cost of material, assembly, welding, painting and fire protection. In the unprotected case the critical temperature method is used with formulae given in Eurocode 3. For both structures investigated the protected one is cheaper than the unprotected. This difference is attributed to the significant difference in thicknesses.