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Extensive spruce beetle mortality in southwest Colorado has motivated land managers to respond with landscape scale tree harvesting projects. The byproducts from these projects could be a source of revenue and a valuable raw material, but currently little is known about the effect of tree mortality on wood quality. We destructively sampled 86 Engelmann spruce (Picea engelmannii) trees from ten plots on the Rio Grande National Forest, and analyzed tree rings to determine mortality year. Time-since-death and other variables such as diameter, elevation, and bark retention were used to develop models predicting the deterioration rate from beetle mortality. In a separate mill study, we harvested eleven trees from the Rio Grande National Forest and milled them to dimensional lumber. Lumber tally was recorded, and boards were graded by a certified grader. The field study found that the severity of seasoning checks was most strongly correlated with tree diameter, and the effect of time-since-death was most pronounced at larger diameters. In the mill study, older dead trees produced a lower percentage of select structural lumber than control trees. Results from this study will help land managers use known information such as mortality year and average tree diameter to prioritize treatment areas and maximize sawtimber recovery.

AbstractJuniperus scopulorumis a common tree in the lower elevations of the Rocky Mountains, and is often removed in restoration treatments. This work reports on selected mechanical and physical properties of J. scopulorum. Ten trees were felled and processed, and a static bending machine was used to test 162 specimens. Additionally, 82 ovendried specimens were assessed for shrinkage and density. Results show an air-dry modulus of elasticity (MOE) of 4,611 MPa, air-dry modulus of rupture (MOR) of 68,460 kPa, green MOE of 3,846 MPa, green MOR of 46,760 kPa, specific gravity of 0.4184 (green basis), and shrinkage value of 7.956 percent. These numbers suggest several new uses for the wood including highway signage, guardrails, and bioenergy feedstock.

More than 1 in 10 people are thought to experience a mental health problem during adolescence, with most adult psychopathology beginning during this time. Experiences of stress or adversity during childhood are important risk factors for poorer mental health outcomes and are also associated with alterations in neurodevelopment. There is evidence to suggest that this relationship is mediated by inflammation and the immune system. The eBRAIN study (The Impact of Early Adversity on Trajectories of Brain Maturation and Mental Health in Young Adolescents) will assess how early life adversity might affect trajectories of brain development throughout adolescence, whether these neurobiological changes are associated with psychopathology, and if they can potentially be explained by an activation of the immune system.

AbstractRussian olive (Elaeagnus angustifolia) is an invasive tree that is the target of many restoration efforts across the United States. These removals are very expensive and generate large amounts of woody biomass waste that currently goes unused. The attractive grain and color of the wood has motivated some mills to process Russian olive and sell it for artisan uses. Some research exists on Russian olive biomass utilization, but no studies have been done on its use as a solid-sawn wood product. The Colorado State Forest Service nursery has hundreds of Russian olives on its property slated for removal. This presented the opportunity to conduct an economic analysis on the potential for increased utilization of Russian olive wood. An inventory of standing trees was conducted to find the volume of merchantable wood and estimate the potential lumber yield. Additionally, a sample of the trees was removed and milled, with actual costs and lumber yields tracked throughout the process. Findings from the two studies indicate that removal and disposal of merchantable material with no utilization would cost $30,254.10. Using the estimated 1445.4 ft3of merchantable wood and 86.0 yd3of mulch could generate revenues of $16,659.63 and bring net cost down to $21,544.17, after accounting for additional expenses.

AbstractColorado's forests have been decimated by a mountain pine beetle outbreak. The mountain pine beetle introduces a blue-stain fungus into the trees, lowering the economic value of the wood. As a result, forest product manufacturing opportunities using beetle-killed trees are limited. One possibility is to use beetle-killed trees to make cut stock, which is lumber that has been cut into specified length, width, and thickness requirements from a cant, lumber, or glued-up panels. The White River Conservation District commissioned this study to determine if a relationship existed between the amount of time beetle-killed trees remain standing dead and the recovery rate for cut stock material from those trees. Conducted in north-central Colorado and south-central Wyoming, this study found that enough material does exist in beetle-killed lodgepole pine trees to produce cut stock but that a tree's diameter at breast height is a better predictor for the cut stock recovery rate from the logs rather than the time spent standing dead on the stump. Given the increasing likelihood that beetle-killed trees will blow down as time passes, incentives for increased beetle-killed wood utilization should be developed quickly.

AbstractOvercrowded forests have allowed several catastrophic wildfires to burn in Colorado. Many of these fires have received national attention and inspired large public expenditures into community wildfire mitigation projects. Forestry projects in Colorado have shifted away from traditional logging and toward service-type projects, such as forest thinning and defensible space, and Colorado's forestry contractors are essential in realizing forest management objectives in the state. Many southeastern and northeastern states conduct regular surveys of forestry contractors to better understand their attributes and ability to adapt to changing conditions. This article presents results of a Colorado forestry contractor survey conducted in 2014. Objectives of this survey were to gain statistical information about the contractors, establish a baseline for future surveys, and determine the capacity of the workforce to address the state's forest health issues. The survey revealed a diminished workforce that has struggled to find identity following policy changes and economic events of the 21st century. This survey also revealed that with the current contractor capacity, Colorado will be unable to face the many threats to forest health and prevent catastrophic wildfire.

AbstractAimsLower parental education has been linked to adverse youth mental health outcomes. However, the relationship between parental education and youth suicidal behaviours remains unclear. We explored the association between parental education and youth suicidal ideation and attempts, and examined whether sociocultural contexts moderate such associations.MethodsWe conducted a systematic review and meta-analysis with a systematic literature search in PubMed, PsycINFO, Medline and Embase from 1900 to December 2020 for studies with participants aged 0–18, and provided quantitative data on the association between parental education and youth suicidal ideation and attempts (death included). Only articles published in English in peer-reviewed journals were considered. Two authors independently assessed eligibility of the articles. One author extracted data [e.g. number of cases and non-cases in each parental education level, effect sizes in forms of odds ratios (ORs) or beta coefficients]. We then calculated pooled ORs using a random-effects model and used moderator analysis to investigate heterogeneity.ResultsWe included a total of 59 articles (63 study samples, totalling 2 738 374 subjects) in the meta-analysis. Lower parental education was associated with youth suicidal attempts [OR = 1.12, 95% Confidence Interval (CI) = 1.04–1.21] but not with suicidal ideation (OR = 1.05, 95% CI = 0.98–1.12). Geographical region and country income level moderated the associations. Lower parental education was associated with an increased risk of youth suicidal attempts in Northern America (OR = 1.26, 95% CI = 1.10–1.45), but with a decreased risk in Eastern and South-Eastern Asia (OR = 0.72, 95% CI = 0.54–0.96). An association of lower parental education and increased risk of youth suicidal ideation was present in high- income countries (HICs) (OR = 1.14, 95% CI = 1.05–1.25), and absent in low- and middle-income countries (LMICs) (OR = 0.91, 95% CI = 0.77–1.08).ConclusionsThe association between youth suicidal behaviours and parental education seems to differ across geographical and economical contexts, suggesting that cultural, psychosocial or biological factors may play a role in explaining this association. Although there was high heterogeneity in the studies reviewed, this evidence suggests that the role of familial sociodemographic characteristics in youth suicidality may not be universal. This highlights the need to consider cultural, as well as familial factors in the clinical assessment and management of youth's suicidal behaviours in our increasingly multicultural societies, as well as in developing prevention and intervention strategies for youth suicide.

We have built a coupled master oscillator and a slave oscillator optical parametric oscillator (OPO) system that provides single-frequency, pulsed radiation in the midwave infrared (MWIR). The direct-diode-pumped master OPO provided narrow-band (<6-MHz, instrument-limited), tunable MWIR cw radiation that was used to seed a higher-peak-power pulsed slave OPO. When seeded directly at the MWIR idler, the pulsed output of the slave OPO was constrained to oscillate on a single longitudinal mode even though the slave OPO is pumped by a multilongitudinal-mode laser source. The linewidth of the pulsed output has been measured to be <220 MHz (instrument limited), which is well suited for coherent differential absorption lidar applications.

ABSTRACT Landing Craft Air Cushions (LCACs) are transported overseas in the well decks of amphibious ships. With Fleet downsizing and increasing deployments and operational tempos, there may not be enough well deck slots to carry the required LCACs to the mission area. Additional transport capability may be needed to meet a number of expanding missions for the LCAC. To address this potential need, Carderock Division Naval Surface Warfare Center was tasked by the Naval Sea Systems Command to determine if existing government shipping assets can transport the LCAC and, if feasible, to design and test interface systems for these ships. Two heavy lift barge ships in the Ready Reserve Force, the Sea Barge (SEABEE) and the Lighter Aboard Ship (LASH), showed potential in carrying LCACs. The LCAC/SEABEE interface system was designed and successfully tested. The tests determined the system provides the SEABEE ship with transport capability for up to five slightly loaded LCACs. The LCAC/LASH interface system, once demonstrated through ship tests, should allow up to six unloaded LCACs to be carried on the LASH ship. The SEABEE and LASH interface systems provide joint mission planners with a new capability to transport LCACs overseas.

Methods for applying uniformly distributed loads to structures are evaluated. A detailed description is presented for a pneumatic pressure bag (airbag) testing machine built by researchers at Virginia Polytechnic Institute and State University. A 48 in. (1.219 m) square steel plate with an average thickness of 0.498 in. (0.01265 m) was tested to determine whether the machine delivers a true uniformly distributed load. Experimental results are compared to an analytical solution obtained using the ABAQUS finite element program.Results show that the deflection pattern of the plate along its length at midspan is parabolic, with deflections being greatest at the free edges and least at the plate center. Errors range from 0.6% at one free edge to 3.8% at the other. The error at the plate center is 1.4%. The close agreement between finite element and experimental values indicates that the load applied by the airbag testing machine is a good approximation of a truly uniform load.

Ketamine as an antidepressant improves anhedonia as early as 2 hours after infusion. These drug effects are thought to be exerted via actions on reward-related brain areas—yet these actions remain largely unknown. Our study investigates ketamine’s effects during the anticipation and receipt of an expected reward, after the psychotomimetic effects of ketamine have passed, when early antidepressant effects are reported.

The articl presents social media post on issue of 8integrations and empowerment and employment of women in the U.S. Navy.

Several letters to the editors are presented in response to the article which discusses revisions to Army Regulation 670-1, reviewing of the social media accounts of the applicants, and the case of Brigadier General Jeffrey Sinclair.