Unit Cohesion Research Articles

Two-dimensional deep-seated slope stability analysis of embankments over stone column-improved soft clay

A two-dimensional (2D) finite difference method was adopted in this study to estimate the factor of safety (FS) against deep-seated failure of embankments over stone column-improved soft clay based on individual column and equivalent area models. In the equivalent area model, the equivalent parameters (unit weight, cohesion, and friction angle) for the improved area were estimated based on the area average of the parameters from stone columns and soft clay. The factors influencing the FS against deep-seated failure of embankments over stone column-improved soft clay were investigated including the spacing, size, and friction angle of stone columns, cohesion of soft clay, friction angle and height of embankment fill, and existence of ground water. Based on the numerical results, a reduction factor was proposed to account for the difference in the FS when the individual column model is converted to the equivalent area model. The effects of the influence factors on the reduction factor were also investigated. The comparative study shows that the FS values obtained by the equivalent area model are higher than those by the individual column model. The results of these analyses are summarized into a series of design charts, which can be used in engineering practice. A reduction factor for FS of 0.90 is appropriate to convert the calculated FS by the equivalent area model to that by the individual column model based on the current study. Furthermore, the existence of the water table results in lower FS values than the cases without considering a water table because the groundwater reduces the shear strength of the improved foundation.

Alcohol use and misuse within the military: A review

Traditionally alcohol has been used by the military to cope with the intense stress of battle but also as a way of mediating the transition from the heightened experience of combat to routine safety. The use of alcohol has divided medical opinion. Some doctors viewed it as wholly harmful to both social and occupational function and to health, while others argued that alcohol had a specific role in lifting morale, aiding unit cohesion and protecting soldiers from adjustment disorders. Although alcoholism has always been identified as incompatible with military service, the effects of habitual heavy drinking among military personnel are less well understood. Recent studies have suggested that young single males and those who have undergone particularly stressful experiences are at greatest risk of misusing alcohol. These associations, observed in the aftermath of recent conflicts in Iraq and Afghanistan, have again raised questions about the place of alcohol in military culture.

Childhood Adversity and Suicidal Ideation in a Clinical Military Sample: Military Unit Cohesion and Intimate Relationships as Protective Factors

Suicide risk and protective factors among 5,187 active duty service members who presented for services at a military outpatient behavioral health clinic were examined. Results indicated that childhood adversity was a significant predictor of suicidal ideation even after controlling for legal, work, financial, and relationship problems, and psychiatric disorders (alcohol abuse, depression, and posttraumatic stress disorder). Childhood adversity was significantly higher among service members who reported prior suicide attempts as compared with service members who did not report prior suicide attempts. The presence of an intimate partner was inversely associated with suicidal ideation. Military unit support moderated the relation between childhood adversity and suicidal ideation, such that this association was positive at lower, but not higher, levels of unit support.

Training Experiences as Mediators of the Association Between Gender-Role Egalitarianism and Women’s Adjustment to Marine Recruit Training

Women may face particular challenges adjusting to the military environment, in part due to their numerical minority status in a traditionally male culture. In addition, women are more likely than men to experience the added stressor of sexual harassment. We examined several potential mediators of the relationship between gender-role egalitarianism and adjustment to boot camp training in a sample of 658 female U.S. Marine recruits. Results indicated that sexual harassment, performance stress, and unit cohesion mediated the relationship between egalitarianism and mental health symptomatology. These findings suggest that beliefs about gender roles are important to consider in efforts to improve women’s adjustment in the military.

Posttraumatic Stress in U.S. Marines: The Role of Unit Cohesion and Combat Exposure

Combat exposure is a consistent predictor of posttraumatic stress (PTS). Understanding factors that might buffer the effects of combat exposure is crucial for helping service members weather the stress of war. In a study of U.S. Marines returning from Iraq, hierarchical multiple regression analyses revealed that unit cohesion and combat exposure predicted PTS, depression, and anger. Furthermore, results indicated that unit cohesion may be an important buffer, possibly limiting the development of PTS and depression following combat exposure.

Exploring Pre-enlistment and Military Factors Associated With the Morale of Members of the UK Armed Forces

There is a paucity of evidence to show the importance of morale within military units. The aim of this study was to explore how pre-enlistment and postenlistment factors influence morale and to ascertain which has the greater contribution. A cross-sectional study of the UK military involved in operations to Iraq was conducted between 2004 and 2006. The sample was randomly selected and was representative of the UK Armed Forces. Data were collected via questionnaires and included measures on unit cohesion and leadership, childhood adversity, and current service factors (e.g., whether individuals deployed as individuals or within formed units). Although childhood adversity was found to affect self-reported morale, current service factors were found to have a greater influence.

The Inclusive Command: Voluntary Integration of Sexual Minorities into the U.S. Military

This essay reexamines the cohesion problem, which many members of Congress cited as the primary rationale for the Ask Don't Tell (DADT) policy currently enforced in the U.S. Military. As an alternative to DADT, we propose the formation of two alternative command structures to which service members would be assigned to assign themselves, depending upon their stated willingness to serve with gay people. Soldiers who are willing to serve with gay people would be assigned to commands. Service members who are not willing to serve with gay people would be assigned to exclusive commands which would continue to operate under the DADT regime. The benefits of the inclusive units would be threefold: amelioration (of current discrimination), demonstration (that DADT is not necessary to preserve unit cohesion), and realignment of political allies and enemies (creating a common cause for pro-gay legislators on the left and pro-defense legislators on the right). The proposal is dynamic, not static. The hope is that inclusive commands would so effectively demonstrate the benefits of integration that, over time, increasing numbers of service members would opt for integrated units. From there, the step to universal, mandatory integration of sexual minorities into the armed forces would be smaller and more easily taken. The essay explores some of the implementation issues likely to arise with inclusive commands.

Sensitivity Study of Physical Limits on Ground Motion at Yucca Mountain

Abstract Physical limits on ground-motion parameters can be estimated from spontaneous-rupture earthquake models but are subject to uncertainties in model parameters. We investigate physical limits at Yucca Mountain, Nevada, and assess sensitivities due to uncertainties in fault geometry, off-fault rock strength, the seismogenic depth, fault zone structure, and undrained poroelastic response of the fluid pressure. For the extreme scenario of nearly complete stress drop on the Solitario Canyon fault, peak ground velocity (PGV) at a site near the fault is sensitive to deep fault geometry and cohesive strength of shallow geologic units, while it is relatively insensitive to fault zone structure, the seismogenic depth, and pore-pressure response. Taking previous estimates of Andrews et al. (2007) as a benchmark, a 10° reduction in dip (from 60° to 50°) of the Solitario Canyon fault at depth, combined with doubled cohesion of shallow units, can increase both horizontal and vertical PGVs by over 1 m/s, to values exceeding 5 m/s. In a lower stress-drop scenario (constrained by regional extremes of coseismic slip inferred from the paleoseismic record), PGV is most sensitive to fault geometry at depth, is only modestly affected by fault zone structure, and is insensitive to cohesion of shallow units and pore-pressure response. Effects of rock strength on spectral acceleration are significant only at short periods (i.e., less than 3 s). The dipping normal-fault models predict asymmetric inelastic strain distributions with respect to the fault plane, with more intense inelastic deformation on the hanging wall, though that asymmetry may be moderated by poroelastic effects.

Mental health of UK military personnel while on deployment in Iraq

Most research on the mental health of UK armed forces personnel has been conducted either before or after deployment; there is scant evidence concerning personnel while they are on deployment. To assess the mental health of UK armed forces personnel deployed in Iraq and identify gaps in the provision of support on operations. Personnel completed a questionnaire about their deployment experiences and health status. Primary outcomes were psychological distress (General Health Questionnaire-12, GHQ-12), symptoms of post-traumatic stress disorder (PTSD) and self-rating of overall health. Of 611 participants, 20.5% scored above the cut-off on the GHQ-12 and 3.4% scored as having probable PTSD. Higher risk of psychological distress was associated with younger age, female gender, weaker unit cohesion, poorer perceived leadership and non-receipt of a pre-deployment stress brief. Perceived threat to life, poorer perceived leadership and non-receipt of a stress brief were risk factors for symptoms of PTSD. Better self-rated overall health was associated with being a commissioned officer, stronger unit cohesion and having taken a period of rest and recuperation. Personnel who reported sick for any reason during deployment were more likely to report psychological symptoms. Around 11% reported currently being interested in receiving help for a psychological problem. In an established operational theatre the prevalence of common psychopathology was similar to rates found in non-deployed military samples. However, there remains scope for further improving in-theatre support mechanisms, raising awareness of the link between reporting sick and mental health and ensuring implementation of current policy to deliver pre-deployment stress briefs.

Coping, mastery, stress appraisals, mental preparation, and unit cohesion predicting distress and performance: a longitudinal study of soldiers undertaking evacuation tasks

The study aimed to assess the associations of psychological and military variables with distress and performance evaluation among 168 Israeli soldiers who took part in evacuating fellow Israeli civilians in the summer of 2005 during the disengagement from Gaza. Coping, mastery, stress appraisals, mental preparation, unit cohesion, and psychological distress were assessed at T1, one to two weeks before the disengagement. A sub-sample of 68 of the 168 soldiers completed the distress measure again at T2, eight to nine weeks after T1, together with performance evaluation of the disengagement task. The main findings indicated positive associations of T1 distress with high T1 emotion-focused coping, and negative associations with education and T1 mastery. Emotion-focused coping at T1 predicted low performance evaluation at T2, while mental preparation at T1 predicted high performance evaluation at T2. Stress appraisals at T1 were found to be an important mediator of the associations of T1 coping, mastery, unit cohesion, and mental preparation with T1 distress. Similar mediator results were found for T2 performance evaluation.

Beyond the Brotherhood: Reassessing US Army Combat Relationships in the Second World War

The conventional wisdom that portrays US combat soldiers in World War II as a 'band of brothers' owes much to Hollywood and popular history, and distorts serious understanding of the relationships within combat units of the US Army. This article examines this idea in the context of theories of unit cohesion and combat motivation and suggests a more complex understanding of these issues.

Military Reviews All Aspects of Suicide-Prevention Efforts

Back to table of contents Previous article Next article Professional NewsFull AccessMilitary Reviews All Aspects of Suicide-Prevention EffortsAaron LevinAaron LevinSearch for more papers by this authorPublished Online:1 Oct 2010https://doi.org/10.1176/pn.45.19.psychnews_45_19_011AbstractThe U.S. military services must alter their training, culture, and administrative structure to stem the steadily rising number of suicides in their ranks, according to a new report from a Department of Defense (DoD) task force.Among the 49 findings and 76 recommendations in the report, mandated last year by Congress, is a call for a suicide-prevention division in the department to “standardize policies and procedures with respect to resiliency, military fitness, life skills, and suicide prevention.”Training for everyone from recruits to top-level officers should include interpersonal and leadership skills to promote the well-being of troops and reduce the stigma attached to seeking help.The incidence of suicide has continued to rise among service members despite a plethora of programs and services intended to combat it.To date, each service branch has developed and carried out its own suicide-prevention programs, which are often overlapping and uncoordinated, according to the report.The DoD document, issued at the end of August, came barely a month after the U.S. Army tackled suicide prevention in its own 350-page report (Psychiatric News September 3). The Army report emphasized a need for tighter discipline and greater awareness of high-risk behavior by soldiers, along with better access to mental health care.The two reports offer a “complementary perspective” on the problem, said a psychiatrist who served on the DoD panel.“We wanted to take a public-health approach to suicide prevention,” said Col. John Bradley, M.C., chief of psychiatry at Walter Reed Army Medical Center and the National Naval Medical Center in Bethesda, Md.That approach began with the task force looking at what was and wasn't working in military and civilian suicide-prevention models, he said, in an interview.The new report focused its findings and recommendations on four areas: organization and leadership; wellness enhancement and training; access to and delivery of quality care; and surveillance, investigations, and research.U.S. military forces have been worn down by frequent deployments separated by insufficient time to recover between the overseas assignments, said the report. “Stress on the force must be reduced.”That may be a policy issue for the politicians to deal with, but there is an immediate need to develop skills to counter that stress.“People need to be maximally resilient,” said Bradley. “We need a culture where resilience and help seeking are rewarded, but there are still stigma and bias against help seeking because it identifies a person as having a problem.”Sometimes even policies intended to protect soldiers with physical or mental health problems can paradoxically keep them from getting treated, he said.The relatively short “dwell” time at home between deployments means that soldiers may not yet be stabilized and are thus ineligible for their next deployment.“That blocks their career progression and reduces unit cohesion,” said Bradley.Officers and noncommissioned officers should be held accountable for “ensuring a positive command climate” to promote overall fitness and encourage service members to seek help when needed.In addition, the services must expand access to and delivery of evidence-based mental health services that use electronic health records to integrate the work of chaplains, crisis hotline workers, and primary care and mental health clinicians.Finally, the report called on the Pentagon to integrate research efforts to shed more light on programs.“DoD does not have an effective standardized approach to suicide surveillance,” said the report. “Because a gold standard has not been established for evaluation, the task force was unable to grade service suicide programs.”For example, the report's authors urged that suicide investigations should better document the last hours, days, and weeks of those who attempt or commit suicide.The psychiatric community can help by focusing attention on access to and quality of care for service-related behavioral health problems, said Bradley.“The Challenge and the Promise: Strengthening the Force, Preventing Suicide, and Saving Lives” is posted at <www.health.mil/dhb/downloads/Suicide%20Prevention%20Task%20Force%20final%20report%208-23-10.pdf>. ISSUES NewArchived

Sleep quality in treatment-seeking veterans of Operations Enduring Freedom and Iraqi Freedom: The role of cognitive coping strategies and unit cohesion

Objective Sleep difficulties are common in individuals exposed to stress or trauma, and maladaptive cognitive coping strategies, such as worry and fear of losing vigilance, as well as low social support, may further impair sleep quality. This study examined the severity and correlates of sleep difficulties in a sample of treatment-seeking veterans of Operations Enduring Freedom and Iraqi Freedom (OEF–OIF). Method A total of 167 OEF–OIF veterans seeking behavioral or primary care services completed a questionnaire containing measures of sleep quality, combat exposure, psychopathology, fear of loss of vigilance, cognitive coping strategies, and unit and postdeployment social support within 1 year of returning from deployment. Results Mean Pittsburgh Sleep Quality Inventory scores in the full sample were indicative of severely impaired sleep. Posttraumatic stress disorder (PTSD) was associated with increased sleep difficulties, most notably sleep disturbances, daytime dysfunction, and sleep quality. Hierarchical regression analysis in the full sample revealed that PTSD symptoms and scores on measures of worry and fear of loss of vigilance were positively associated with sleep difficulties and that scores on a measure of unit member support were negatively associated with sleep difficulties. Among veterans with PTSD, fear of loss of vigilance was positively associated with sleep difficulties and cognitive distraction and unit member support were negatively associated with sleep difficulties. Conclusions Treatment-seeking OEF–OIF veterans report severe sleep difficulties, with more pronounced impairment in veterans with PTSD. The results of this study suggest that interventions to mitigate worry and fear of loss of vigilance and to enhance perceived unit member support may be helpful in reducing sleep difficulties following return from deployment in this population.

Unit Cohesion and PTSD Symptom Severity in Air Force Medical Personnel

Research suggests that military unit cohesion may protect against the development of post-traumatic stress disorder (PTSD). However, equivocal findings have led researchers to hypothesize a potential curvilinear interaction between unit cohesion and warzone stress. This hypothesis states that the protective effects of cohesion increase as warzone stress exposure intensifies from low to moderate levels, but at high levels of warzone stress exposure, cohesion loses its protective effects and is potentially detrimental. To test this theory, we conducted a test for curvilinear moderation using a sample of 705 Air Force medical personnel deployed as part of Operation Iraqi Freedom. Results did not support the curvilinear interaction hypothesis, although evidence of cohesion's protective effects was found, suggesting that unit cohesion protects against PTSD regardless of level of stress exposure.

Modelling Safety Factors of Slope Stability for Open-Pit Mining of Nigerian Tar-Sand Deposits

Slope failure might lead to loss of lives and valuable equipment which would increase overall operational cost of running a mine. The need to have stable slopes in open-pit mining of Nigerian tar sand deposits of Dahomey Basin, Southwestern Nigeria is emphasized in this study. At Loda village, Southwestern Nigeria, samples of the laterite soil and alluvial sand which overlie the tar sand occurrence were subjected to geotechnical tests. Computer simulation of bench face angles was carried out using SLOPE/W Software to determine the bench face angle(s) with the least susceptibility to failure. Unit weight (o), cohesion (c) and angle of internal friction (0) values for the laterite soil were 25 kN/m, 45 kPa and 41 respectively for laterite. The corresponding values for the laterite, soil were 18 kN/m 3 , 0kPa and 34°. These values were used to run the software programme to simulate different bench face angles that could be cut into the two lithologic units. Factors of safety values between 3.58 and 1.73 were obtained for bench face angles between 10° and 30° which are least susceptible to failure even when inundation is considered. This research results have enabled us to recommend the use of bench slope angles ranging from 10° and 30° coupled with adequate drainage conditions which should guaranty optimum output.

STUDY OF MECHANICAL PROPERTIES OF COMPACTED MATERIALS GROUND PADS AS RANDOM VARIABLES

The statistic analysis of variability values of mechanical characteristics of compacted soils is done. Also the laws of their distribution are determined. As a result, it is determined that for the deformation modulus, unit cohesion and internal friction angle the logarithmic normal law of distribution is more correct, while for penetration resistance – exponential law.

Health, wartime stress, and unit cohesion: Evidence from Union Army veterans

We find that Union Army veterans of the American Civil War who faced greater wartime stress (as measured by higher battlefield mortality rates) experienced higher mortality rates at older ages, but that men who were from more cohesive companies were statistically significantly less likely to be affected by wartime stress. Our results hold for overall mortality, mortality from ischemic heart disease and stroke, and new diagnoses of arteriosclerosis. Our findings represent one of the first long-run health follow-ups of the interaction between stress and social networks in a human population in which both stress and social networks are arguably exogenous.

Leaving Security in Safe Hands: identity, legitimacy and cohesion in the new Afghan and Iraqi armies

Built by outside powers and targeted against local insurgents, the new national armies of Afghanistan and Iraq are fragile institutions. The legitimacy of these forces is limited in the deeply divided societies in which they exist. Whereas low levels of legitimacy exert a disintegrative pressure upon an army, cohesion counterweighs such pressure. This article engages the theory of military unit cohesion for the purpose of increasing understanding of the challenges to cohesion faced by the new armies of Afghanistan and Iraq. Two main sources of legitimacy for the new armies are discussed: the (ethnic/sectarian) composition of the forces, and their respective missions. Challenges to cohesion are found to depend on how soldiers are recruited and units composed: ethnically/sectarian mixed units may disintegrate because of weak horizontal cohesion; homogeneous units (particularly when recruited as groups and not individually) may splinter off because of weak vertical cohesion. The article also argues that promoting an image of the army as ‘national’ within a society may reduce disintegrative pressures.

The Trials of Homecoming: Odysseus Returns from Iraq/Afghanistan

This lecture introduces some of the poignant challenges and stressors facing service members and their families as they return from combat in Iraq and Afghanistan. A focus on the nature of psychological injuries, as compared with disorders, sets the stage for discussing some central factors necessary for a harmonious transition back home. The article stresses the vital role played by a community of Veterans in healing moral injuries. The importance of effective leadership, sound sleep, and supportive unit cohesion are stressed as vital protective factors in theater. To assist mental health and health clinicians working with Veterans, the article asserts that the prevention of secondary trauma should be ethically obligatory self‐care supported by mental health centers and academic institutions.

Attitudes of Iraq and Afghanistan War Veterans toward Gay and Lesbian Service Members

U.S. policy banning openly gay and lesbian personnel from serving in its military rests on the belief that heterosexual discomfort with lesbian and gay service members in an integrated environment would degrade unit cohesion and readiness. To inform this policy, data from a 2006 survey of Iraq and Afghanistan war veterans are analyzed in this study. Views of these war veterans are consistent with prior surveys of military personnel showing declining support for the policy: from about 75 percent in 1993 to 40 percent in this survey. Among the demographic and military experience variables analyzed, comfort level with lesbian and gay people was the strongest correlate of attitudes toward the ban. War veterans indicated that the strongest argument against the ban is that sexual orientation is unrelated to job performance and that the strongest argument in favor of the ban is a projected negative impact on unit cohesion. However, analyses of these war veterans’ ratings of unit cohesion and readiness revealed that knowing a gay or lesbian unit member is not uniquely associated with cohesion or readiness; instead, the quality of leaders, the quality of equipment, and the quality of training are the critical factors associated with unit cohesion and readiness.