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Abstract: The retrieval algorithms used for optical remote sensing satellite data to estimate Earth's geophysical properties have specific requirements for spatial resolution, temporal revisit, spectral range and resolution, and instrument signal‐to‐noise ratio (SNR) performance to meet biogeoscience objectives. Studies to estimate surface properties from hyperspectral data use a range of algorithms sensitive to various sources of spectroscopic uncertainty, which are in turn influenced by mission architecture choices. Retrieval algorithms vary across scientific fields and may be more or less sensitive to mission architecture choices that affect spectral, spatial, or temporal resolutions and spectrometer SNR. We used representative remote sensing algorithms across terrestrial and aquatic study domains to inform aspects of mission design that are most important for impacting accuracy in each scientific area. We simulated the propagation of uncertainties in the retrieval process including the effects of different instrument configuration choices. We found that retrieval accuracy and information content degrade consistently at >10 nm spectral resolution, >30 m spatial resolution, and >8‐day revisit. In these studies, the noise reduction associated with lower spatial resolution improved accuracy vis à vis high spatial resolution measurements. The interplay between spatial resolution, temporal revisit, and SNR can be quantitatively assessed for imaging spectroscopy missions and used to identify key components of algorithm performance and mission observing criteria.

In order to address the question of oil-induced microfracturing, we propose under specific assumptions (plane circular kerogen flake surrounded by an homogeneous microfractured porous medium) an analytical method for the determination of the oil pressure increase. It is based on a mechanical modelling of the kerogen-oil-rock interaction at the microscopicscale of a kerogen particle. It is shown that the oil pressure tends towards an asymptotic value when the chemical transformation of kerogen is completed. The effect of the macroscopic stress variation during oil formation process proves to be negligible. However, this effect must be taken into account for describing the evolution of oil pressure at earlier stages of oil formation process. The increase in burial depth induces an increase of oil pressure as well as a variation of the macroscopic stress which both determine the microscopic stress field. The possibility of microfracturing depends on the position of the microscopic stress state with respect to the fracture criterion. If the duration of the oil formation process is short enough, so that the macroscopic stress change associated with the corresponding (small) burial depth increase can be neglected, it is found that microfracturing is likely for the usual values of rock tensile strength. However, in the general case, neglecting the macroscopic stress change can significantly overestimate the possibility of fracture initiation due to oil-pressure increase. Considering now the macroscopicscale of the source bed, the evolution equation of the oil pressure are derived within the framework of Biot's poroelasticity theory. The oil pressure rate proves to be the sum of a diffusion term which accounts for oil migration within the source bed, and of two source terms respectively associated with the volume expansion tendency of the kerogen - oil transformation and the overburden pressure increase. Dans le but d'étudier le problème de la microfracturation induite par la génération des hydrocarbures dans les roches mères, nous proposons une méthode analytique pour déterminer l'évolution de la pression de l'huile. Cette méthode est basée sur une modélisation mécanique des interactions kérogène-huile-roche à l'échelle microscopique. Il est montré que la pression de l'huile tend vers une valeur asymptotique quand la réaction de transformation du kérogène en huile s'achève. Les variations des contraintes macroscopiques pendant la formation de l'huile ont des effets faibles. Cependant, ils doivent être considérés pour décrire correctement l'évolution de la pression de l'huile au stade précoce de la génération. L'augmentation de l'enfouissement provoque une augmentation de la pression de l'huile ainsi qu'une augmentation des contraintes macroscopiques. Cela conditionne l'évolution du champ de contraintes microscopiques. La possibilité de microfracturation dépend de la position du champ de contraintes microscopiques par rapport au critère de rupture. Si la durée de la transformation du kérogène en huile est suffisamment courte, de sorte que l'on puisse négliger la variation du champ de contraintes macroscopiques induite par la variation de l'enfouissement, alors, on montre que pour des valeurs usuelles des paramètres mécaniques, la microfracturation est possible. Néanmoins, de façon plus générale, le fait de négliger les variations du champ de contraintes macroscopiques conduit à une surestimation des possibilités de microfracturation induite par l'augmentation de la pression de l'huile. À l'échelle macroscopique (de la roche mère), l'équation qui décrit l'évolution de la pression de l'huile est écrite dans le cadre de la théorie poroélastique de Biot. L'évolution de la pression est donnée par la somme d'un terme de diffusion qui provient de la migration de l'huile dans la roche, et de deux termes respectivement associés à l'expansion volumique de la transformation du kérogène en huile et à l'augmentation de la charge due à l'enfouissement.

One key point for simulating the hydraulic fracturing at basin scale, is to be able to compute the stress tensor. This is generally not addressed in basin model because of the complexity of this problem. In order to get access to the stress tensor we have to assume that:- one of the principal stress is vertical and equals the overburden weight;- the horizontal stress is deduced from the vertical stress with the K0 coefficient that is a function of depth and of the tectonical setting. Consolidation is considered here as the combined effect of the mechanical compaction and the chemical compaction. The mechanical compaction is mainly caused by the rearrangement of grains during burial and could be represented at the macroscopical scale by an elastoplastic rheology. The chemical compaction is considered here as resulting from dissolution-precipitation mechanisms, generally induced by stress (pressure-solution). The chemical compaction could be represented at the macroscopical scale by a viscoplastic rheology. The complete elastoplastic yield is defined by the union of the consolidation elastoplastic yield and of the different failure criteria that could be seen as elastobrittle yields. Thus, the elastoplastic yield is composed of six elementary elastoplastic yields which define the onset of vertical compaction, horizontal compaction, vertical tensile fracturing, horizontal tensile fracturing, subvertical shear fracturing, and subhorizontal shear fracturing. Due to the consolidation, most of the parameters that describe the physical properties of the sediments evolve with the geological times. One difficulty is to quantify the degree of evolution of the porous medium during its geological history. Here, we have chosen to measure the evolution of the sediments by their porosity. The local simulations showed that fracturing may occur is numerous configurations. Some of these configurations indicate that the sediments can reach the limit of its elastic domain and then may initiate some fracturing. In other cases, the sediment changes its loading path but stay at the elastoplastic yield surface. In this case the theoretical considerations are not valid anymore and fracture criteria should be defined in the plastic domain. Fracturation hydraulique à l'échelle des bassins sédimentaires Fracturation hydraulique à l'échelle des bassins sédimentaires Le calcul du tenseur des contraintes est déterminant pour pouvoir simuler la fracturation hydraulique à l'échelle des bassins sédimentaires. Ce calcul n'est généralement pas abordé dans les modèles de bassins en raison de la complexité du problème. Pour pouvoir estimer le tenseur des contraintes, nous sommes alors amenés à formuler les hypothèses suivantes: - une des contraintes principales est verticale et égale, en module, au poids des terrains sus-jacents ; - la contrainte horizontale se déduit de la contrainte verticale à partir d'un coefficient de report K0 qui est une fonction de la profondeur et du contexte géodynamique. La consolidation est supposée être le résultat à la fois de la compaction mécanique et de la compaction chimique. La compaction mécanique est principalement due au réarrangement mécanique des grains pendant l'enfouissement. Elle peut se simuler, à l'échelle macroscopique, par une rhéologie élasto-plastique. La compaction chimique est le résultat des mécanismes de pression-dissolution. Elle peut être simulée, à l'échelle macroscopique, par une rhéologie viscoplastique. La surface de charge est complètement définie par l'union de la surface de consolidation avec les différentes limites de rupture. Cette surface de charge est alors définie par six surfaces élémentaires qui représentent la compaction verticale, la compaction horizontale, la rupture verticale en traction, la rupture horizontale en traction, la rupture subverticale en cisaillement, et la rupture subhorizontale en cisaillement. En raison du processus de consolidation, la plupart des paramètres qui décrivent les propriétés physiques des sédiments évoluent avec l'histoire géologique. Une des difficultés est alors de quantifier le degré d'évolution du milieu poreux. Nous avons choisi ici de mesurer l'évolution des sédiments par leur porosité. Les simulations locales ont montré que la fracturation peut apparaître dans de nombreuses configurations. Dans certaines de ces situations, le sédiment peut atteindre les limites de son domaine élastique et peut alors initier des fractures. Dans d'autres cas, le chargement du sédiment change, mais il reste sur sa surface de charge. Dans ce cas, les considérations théoriques ne sont plus valables et les critères de rupture doivent alors être définis dans le domaine plastique.

Cette étude complète un travail antérieur (Schneider, 1993) qui a permis d'interpréter et de formaliser le modèle de compaction classiquement utilisé dans des simulateurs comme Temispack (Doligez et al, 1986; Ungerer et al. , 1990). Le nouveau modèle présenté ici se distingue du précédent par l'introduction d'une composante viscoplastique dans l'équation qui décrit la compaction. L'ajout de cette composante permet de prendre en compte de façon macroscopique les phénomènes visqueux de la compaction comme la pression-dissolution. En utilisant des valeurs de coefficients de viscosité extrapolées à partir d'expériences de laboratoire, une étude de sensibilité montre que la déformation visqueuse est significative pour des bassins vieux de plus de 1 Ma. Certains tests montrent que le coefficient de viscosité peut être calibré simplement à partir de données de puits et d'expériences simples de laboratoire. À partir de données extraites de la littérature, il a été possible de calibrer un coefficient de viscosité de 2,5 GPa. Ma (= 8 x 10 puissance (22) Pa. s) pour la craie. This article contains formulas (***) which can not be displayed on this screen. This study completes a previous work (Schneider, 1993) in which the compaction model that is conventionally used in models such as Temispack (Doligez et al. , 1986, Ungerer et al. , 1990), has been interpretated and formalized. The new model described here differs from the previous one by the introduction of a viscoplastic component in the formulation of the stress-strain relationships. The addition of this component, allows to take into account, at a macroscopical scale, viscous phenomena of compaction such as pressure solution. The volumetric rheology is then defined by the following system of equations:(***)where phi is porosity; sigma is the effective stress defined as the difference between the overburden weight and the pore pressure; phi index (m) is the maximum effective stress reached by the sediment during its burial. The elastoplastic parameters (Ee, Ea, Eb, phi index (a), phi index (b), phi index (r)) of function Beta can be easily calibrated from experimental data or from well logs data (Hamilton, 1959; Schneider et al, 1993). The viscoplastic parameters (µ index b, phi to the power of (min)) of function alpha can be calibrated from well logs data as shown in this study. They can also be extrapolated, for a given lithology, from experimental data (Gratier and Guiguet, 1986). A sensitivity analysis has been carried out with different values of extrapolated viscous coefficients. The viscous deformation is important (50% of the total strain) for basins older than 1 Ma when the viscous coefficient is lower than a critical value of 10 MPa. Ma This critical value is equal to 100 MPa. M for basin older than 10 Ma and is equal to 1000 MPa. Ma for basin older than 100 Ma. With field data from Scholle (1977), it is possible to estimate the elastoplastic and viscoplastic parameters which define a chalk rheology. Assuming that chalk which had no suffer diagenesis, has been compacted along an elastoplastic path, it is possible to calibrate easily the elastoplasic parameters. Such a calibration can be also performed with laboratory measurements as suggested by Hamilton (1959). When chalk has suffered diagenesis, we assume that the present-day porosity versus effective-stress relationships, extracted from well logs, result both from elastoplastic deformation and viscoplastic deformation. With this assumption, chalk viscosity is evaluated around 2. 5 GPa. Ma. According to the sensitivity analysis, chalk pressure solution (viscoplastic deformation) is noteworthy (10% of the total strain) for basin older than 20 Ma. In conclusion, this model allow to take into account, in a realistic way, pressure solution phenomena which participate to sediments compaction. The major hypotheses are : (1) the transport of species in solution can be neglected in regard to the size of the considered cells; (2) the viscous coefficient is constant for a given lithology; (3) mechanical compaction and chemical compaction depend on the same effective stress. In spite of these restrictive hypotheses, the model gives solutions which are physically acceptable.

Cet article est consacré à l'étude de l'affaissement de la surface du sol provoqué par la production de fluides (eau, hydrocarbures). On présente d'abord les méthodes disponibles pour mesurer cette subsidence, qui atteignent aujourd'hui une grande précision. A partir des cas répertoriés dans la littérature, on met en évidence les mécanismes qui sont à l'origine de la subsidence : compaction du réservoir et compaction des aquitards en relation avec la déplétion, mécanismes liés à l'injection de fluides dans certains cas particuliers (fluage thermique, action de l'eau sur la craie). Ces mécanismes doivent être pris en compte par des modèles progressivement enrichis par la description géologique, pétrophysique et mécanique confrontée aux mesures en place. Le contrôle de la subsidence repose sur le contrôle de la pression en place, maintenue par un fluide compatible avec la formation. Si ce contrôle est mis en oeuvre assez tôt le risque de subsidence est pratiquement nul. This article is devoted to the investigation of soil surface subsidence caused by the production of fluids (water, oil and gas). It first describes the methods available for measuring this subsidence, methods that have become extremely accurate today. Cases are selected from the literature to identify the mechanisms causing subsidence: reservoir and aquifer compaction associated with depletion, mechanisms connected with fluid injections in specific cases (thermal creep, action of water on chalk). These mechanisms must be taken into account by models progressively enriched with geological, petrophysical and mechanical descriptions, substantiated by in situ measurements. Subsidence control demands the control of the in situ pressure, maintained by a fluid compatible with the formation. If this control is applied early enough, the risk of subsidence is virtually nil.

Cet article présente un modèle de compaction des sédiments pour simulateurs de bassins sédimentaires. Dans ce modèle, les concepts précédemment utilisés dans le modèle TEMISPACK sont généralisés et décrits en s'inspirant des formalismes propres à la mécanique des roches et à la mécanique des sols. La compaction des sédiments est décrite, à l'échelle des temps géologiques, par un modèle élasto-plastique où les modules d'incompressibilité et d'écrouissage croissent lorsque la déformation augmente et où le seuil de plasticité est variable. La rhéologie est définie par une relation qui lie la porosité (ou le volume) du sédiment à la contrainte effective moyenne en se plaçant dans l'hypothèse de déformation oedométrique. Ce modèle à rhéologie volumiquea été testé sur le logiciel COMP1D qui simule, en 1D, l'histoire géologique d'une colonne sédimentaire. Ce modèle ne doit être considéré que comme un premier pas vers un formalisme plus complet. This article describes a sediment compaction model for sedimentary basin simulators. In this model, the concepts previously used in the TEMISPACK model are generalized and described on the basis of formalisms inherent in rock mechanics and soil mechanics. Sediment compaction is described on the geologic time scale by an elastoplastic model (Fig. 1) in which the moduli of incompressibility and strain hardening increase as deformation increases and in which the plasticity threshold varies. The rheology is defined by an equation connecting the porosity (or volume) of the sediment to the mean effective stress by situating itself within the hypothesis of consolidometric deformation. This model is quite similar to the ones used in soil mechanics. It differs only by the choice of the equations linking the volumic variation of the porous medium to the variation of the mean effective stress likewise, in this part coefficient alpha introduced in the definition of effective stress is close to 1, which is coherent with the hypothesis of considering the grains making up the skeleton as being indeformable. COMP1D is a software that makes a 1D simulation of the geologic history of a sedimentary column. It integrates the physical phenomena described in the first part. The geometric variations caused by sedimentation, erosions and compaction are taken into consideration by introducing various Lagrangian coordinate systems (Fig. 2). The temperature is imposed by a surface temperature and a gradient. The boundary conditions are the ones conventionally used in basin simulators. There are various versions of the software corresponding to different numerical approaches. Our problem was discretized by finite-element methods with linear shape functions, finite-element methods with quadratic shape functions, and finite-volume methods. Numerous tests showed that the pressure solution to convergence is identical for all such methods. However finite-element methods cannot be used to compute a velocity field for the fluid that gives perfect local conservation. This local conservation is absolutely necessary for coupling a transport equation (heat equation, saturation equation for two-phase flows) with the computing of the pressure of the fluid. Only finite-volume methods, which handle nonlinearities (Newton's method) correctly, are locally perfectly conservative. This model improves preceding models, mainly by introducing the concept of elasticity. However, as things now stand and from the theoretical standpoint, it is valid only in the superficial layer of sediments. Its extension to deeper layers is acceptable in basin simulators only because the porosity variation is slight. The introduction of an alpha coefficient in the definition of the effective stress seems necessary. However, the fact of taking this coefficient different from 1 must, for reasons of coherence, lead us to give increased consideration to the mechanical deformations of the grains. The results obtained with this model show that, when consideration is given to variations in the density of the fluid and solid with pore pressure and temperature, this makes for an important change in the porosity values and pressure excess computed. However, these variations are less than the uncertainties concerning the data during a case study. When coefficients alpha and Ko (or v) are taken into consideration, the results obtained are different, but their order of magnitude remains compatible with those given by the model, which does not take these coefficients into consideration (Fig. 3). These concepts will have to be tested for real cases by comparison with more conventional approaches.

Experiments were performed in the purpose of studying the isotopic consequences of the diffusional transport of hydrocarbon gases through sediment rocks. Linked to a numerical model, these gas diffusion experiments through a shale porous plug allowed us to correlate porosity and diffusivity of the migration medium. Significant isotopic fractionations (carbon and hydrogen) of methane, and ethane at a lesser degree were observed. This is in contradiction with the actual dogma of isotope geochemistry of natural gases which claims that no fractionation occurs during gas migration. The genetic characterization of natural gases by using the isotopic signature of methane appears as an ambiguous method. Plusieurs expériences ont été réalisées dans le but d'étudier les conséquences isotopiques du transport par diffusion des gaz hydrocarbures au travers des roches sédimentaires. Associées à un modèle numérique, ces expériences de diffusion au travers d'une membrane d'argile reconstituée nous ont permis de corréler deux paramètres pétrophysiques du milieu de migration : la porosité et la diffusivité. D'importants fractionnements isotopiques ont été observés au cours de la diffusion du méthane et, à plus petite échelle, lors de la diffusion de l'éthane. Ces résultats remettent en cause le dogme actuel de la géochimie isotopique des gaz naturels qui stipule que la migration des gaz ne peut induire de fractionnements isotopiques. En conséquence, les méthodes de caractérisation génétique des gaz naturels utilisant la signature isotopique du méthane apparaissent comme insuffisantes.

In 2009, the ADFM leadership wrote an Annals commentary describing the phases of the organization to date (1); in 2012 they built on this piece, sharing ADFM's new strategic plan. [...]

IntroductionImprovement in posttraumatic stress disorder (PTSD) is associated with better health behavior such as better medication adherence and greater use of nutrition and weight loss programs. However, it is not known if reducing PTSD severity is associated with smoking cessation, a poor health behavior common in patients with PTSD.Aims and methodsVeterans Health Affairs (VHA) medical record data (2008-2015) were used to identify patients with PTSD diagnosed in specialty care. Clinically meaningful PTSD improvement was defined as ≥20 point PTSD Checklist (PCL) decrease from the first PCL ≥50 and the last available PCL within 12 months and at least 8 weeks later. The association between clinically meaningful PTSD improvement and smoking cessation within 2 years after baseline among 449 smokers was estimated in Cox proportional hazard models. Entropy balancing controlled for confounding.ResultsOn average, patients were 39.4 (SD = 12.9) years of age, 86.6% were male and 71.5% were white. We observed clinically meaningful PTSD improvement in 19.8% of participants. Overall, 19.4% quit smoking in year 1 and 16.6% in year 2. More patients with versus without clinically meaningful PTSD improvement stopped smoking (n = 36, cumulative incidence = 40.5% vs. 111, cumulative incidence = 30.8%, respectively). After controlling for confounding, patients with versus without clinically meaningful PTSD improvement were more likely to stop smoking within 2 years (hazard ratio = 1.57; 95% confidence interval: 1.04-2.36).ConclusionsPatients with clinically meaningful PTSD improvement were significantly more likely to stop smoking. Further research should determine if targeted interventions are needed or whether improvement in PTSD symptoms is sufficient to enable smoking cessation.ImplicationsPatients with PTSD are more likely to develop chronic health conditions such as heart disease and diabetes. Poor health behaviors, including smoking, partly explain the risk for chronic disease in this patient population. Our results demonstrate that clinically meaningful PTSD improvement is followed by greater likelihood of smoking cessation. Thus, PTSD treatment may enable healthier behaviors and reduce risk for smoking-related disease.

Laser resonance ionization spectroscopy was performed on the rare einsteinium isotopes Es253-255 at the RISIKO mass separator in Mainz. With low sample sizes ranging down to femtograms, the prominent 352 nm-ground-state transition was measured in all three einsteinium isotopes, and four additional ground-state transitions were measured in Es254. Hyperfine-structure analysis resulted in assigned spin values of I(Es254)=7 and I(Es255)=7/2. From the extracted coupling constants, nuclear magnetic dipole moments of μI(Es254)=3.42(7)μN and μI(Es255)=4.14(10)μN as well as spectroscopic electric quadrupole moments of Qs(Es254)=9.6(1.2)eb and Qs(Es255)=5.1(1.7)eb were derived. Our value for Es254 deviates from the value of |μI(Es254)|=4.35(41)μN extracted from the angular anisotropy of α-radiation emitted by Es254.

BackgroundClinical trials reveal posttraumatic stress disorder (PTSD) improvement leads to decreased substance use among patients with comorbid substance use disorder (SUD). Using administrative medical record data, we determined whether clinically meaningful PTSD Checklist (PCL) (≥20 points) score decreases were positively associated with SUD treatment utilization.MethodsWe used a retrospective cohort of Veterans Health Affairs (VHA) medical record data (2008-2015). PTSD Checklist (PCL) scores were used to categorize patients into those with a clinically meaningful PTSD improvement (≥20 point decrease) or not (

AimPrescription opioid analgesic use (OAU) is associated with increased risk of cardiovascular disease (CVD). OAU is more common in patients with than without posttraumatic stress disorder (PTSD), and PTSD is associated with higher CVD risk. We determined whether PTSD and OAU have an additive or multiplicative association with incident CVD.Methods and resultsVeterans Health Affairs patient medical record data from 2008 to 2015 was used to identify 2861 patients 30-70 years of age, free of cancer, CVD and OAU for 12 months before index date. We defined a four-level exposure variable: 1) no PTSD/no OAU, 2) OAU alone, 3) PTSD alone and 4) PTSD+OAU. Cox proportional hazard models estimated the association between the exposure variable and incident CVD. The mean age was 49.0 (±11.0), 85.7% were male and 58.3% were White, 34.4% had no PTSD/no OAU, 32.9% had PTSD alone, 10.6% had OAU alone, and 22.1% had PTSD+OAU. Compared with patients with no PTSD/no OAU, those with PTSD alone were not at increased risk of incident CVD (hazard ratio = 0.82; 95% confidence interval (CI): 0.63-1.17); however, OAU alone and PTSD+OAU were both significantly associated with incident CVD (hazard ratio = 1.99; 95% CI:1.36-2.92 and hazard ratio = 2.20; 95% CI: 1.61-3.02). There was no significant additive or multiplicative PTSD and OAU association with incident CVD.ConclusionOAU is associated with nearly a two-fold increased risk of CVD in patients with and without PTSD. Despite no additive or multiplicative interaction effects, the high prevalence of OAU in PTSD may represent a novel contributor to the elevated CVD burden among patients with PTSD.

BackgroundPosttraumatic stress disorder (PTSD) is associated with increased risk for cardiovascular disease (CVD). Whether clinically meaningful PTSD improvement is associated with lowering CVD risk is unknown.MethodsEligible patients (n = 1079), were 30-70 years old, diagnosed with PTSD and used Veterans Health Affairs PTSD specialty clinics. Patients had a PTSD Checklist score (PCL) ≥ 50 between Fiscal Year (FY) 2008 and FY2012 and a second PCL score within 12 months and at least 8 weeks after the first PCL ≥ 50. Clinically meaningful PTSD improvement was defined by ≥20 point PCL decrease between the first and second PCL score. Patients were free of CVD diagnoses for 1 year prior to index. Index date was 12 months following the first PCL. Follow-up continued to FY2015. Cox proportional hazard models estimated the association between clinically meaningful PTSD improvement and incident CVD and incident ischemic heart disease (IHD). Sensitivity analysis stratified by age group (30-49 vs. 50-70 years) and depression. Confounding was controlled using propensity scores and inverse probability of exposure weighting.ResultsPatients were 48.9 ± 10.9 years of age on average, 83.3% male, 60.1% white, and 29.5% black. After controlling for confounding, patients with vs. without PTSD improvement did not differ in CVD risk (HR = 1.08; 95%CI: 0.72-1.63). Results did not change after stratifying by age group or depression status. Results were similar for incident IHD.ConclusionsOver a 2-7 year follow-up, we did not find an association between clinically meaningful PTSD improvement and incident CVD. Additional research is needed using longer follow-up.

ObjectivePosttraumatic stress disorder (PTSD) is associated with increased risk for cardiometabolic disease. Clinically meaningful PTSD improvement is associated with a lower risk for diabetes, but it is not known if similar associations exist for incident hypertension, hyperlipidemia, and clinically relevant weight loss (i.e., ≥5% loss).MethodMedical record data from Veterans Health Affairs patients with clinic encounters between fiscal year (FY) 2008 to 2015 were used to identify patients with worsening or no PTSD improvement (i.e., PTSD checklist (PCL) score decrease

BackgroundPatients with vs. without posttraumatic stress disorder (PTSD) are more likely to have poor antidepressant medication (ADM) adherence but it is unclear if improved PTSD is associated with ADM adherence. We determined if clinically meaningful PTSD symptom reduction was associated with ADM adherence.MethodsElectronic health record data (2008-2015) was obtained from 742 Veterans Health Affairs (VHA) patients using PTSD specialty clinics with a PTSD diagnosis and PTSD checklist (PCL) score ≥50. The last PCL in the exposure year after the first PCL≥50 was used to identify patients with a clinically meaningful PCL decrease (≥20 point) versus those without (< 20 point). Patients had a depression diagnosis in the 12-months before the exposure year and received an ADM in the exposure year. Proportion of days covered ≥80% in exposure year defined adherence. Confounding was controlled using propensity scores and inverse probability of treatment weighting.ResultsPatients were 42.2 ± 13.1 years of age, 63.9% white and 18.9% had a clinically meaningful PCL decrease. After controlling for confounding variables, patients with vs. without a clinically meaningful PCL decrease were significantly more likely to be adherent (OR = 1.78; 95% CI:1.16-2.73). However, adherence remained low in both patients with and without meaningful PCL decrease (53.5% vs. 39.3%).LimitationsThe sample was limited to VHA patients. Patients may not have taken medication as prescribed.ConclusionsLarge reductions in PTSD symptoms are associated with ADM adherence. Prior literature suggests ADM adherence improves depression symptoms. Thus, PTSD symptom reduction may lead to better depression outcomes.

OBJECTIVE:Posttraumatic stress disorder (PTSD) is associated with poor health behaviors, including low utilization of Veteran Health Affairs (VHA) weight loss programs. It is not known if clinically meaningful PTSD improvement is associated with increased use of weight loss programs. METHODS:Medical record data was obtained from VHA patients who received PTSD specialty care between Fiscal Year (FY) 2008 to FY2012. Clinically meaningful PTSD improvement was defined as ≥20 point PTSD Checklist (PCL) decrease between the first PCL ≥ 50 and a second PCL at least 8 weeks later and within 12 months of the first PCL. Eligible patients, n = 993, were followed through FY2015. Propensity scores and inverse probability of exposure weighting controlled confounding. Cox proportional hazard models estimated the association between clinically meaningful PCL decrease and weight loss clinic utilization. Supplemental analysis compared both PTSD groups vs. no PTSD. RESULTS:Patients were 44.8 (SD ±14) years of age, 88.9% male and 66.8% white. Patients with vs. without a clinically meaningful PCL decrease were more likely to use a weight loss clinic (HR = 1.37; 95%CI:1.02-1.85). Among those with a weight loss encounter, PCL decrease was not associated with the number of encounters (RR = 1.13; 95%CI:0.70-1.81). Compared to no PTSD, patients with PTSD improvement had more weight loss encounters. CONCLUSIONS:Large improvements in PTSD are associated with increased utilization of weight loss programs, and PTSD is not a barrier to seeking weight loss counseling. Research to understand why improvement in PTSD is not related to better weight loss outcomes is needed.

ObjectiveThe aim of this study was to systematically review variables associated with initiation of trauma-centered cognitive-behavioral therapy (TC-CBT) among individuals with posttraumatic stress disorder (PTSD).MethodsPubMed, PsycINFO, Web of Science, Published International Literature on Traumatic Stress (PILOTS), and Scopus were searched in a systematic manner up to 2018, and 26 relevant studies were recovered and analyzed.ResultsThe average weighted initiation rate was 6% in larger hospital systems with a high rate of trauma and 28% in outpatient mental health settings (range 4%-83%). Older age (odds ratio [OR]=1.56, 95% confidence interval [CI]=0.51-1.61), female gender (OR=1.18, 95% CI=1.08-1.27), black or other racial-ethnic minority group (OR=1.16, 95% CI=1.03-1.28), Veterans Affairs PTSD service connection status (OR=2.30, 95% CI=2.18-2.42), mental health referral (OR=2.28, 95% CI=1.05-3.50), greater staff exposure to TC-CBT (OR=2.30, 95% CI=2.09-2.52), adaptability of TC-CBT to staff workflow (OR=4.66, 95% CI=1.60-7.72), greater PTSD severity (OR=1.46, 95% CI=1.13-1.78), and comorbid depression (OR=1.21, 95% CI=1.14-1.29) increased the likelihood of TC-CBT initiation, whereas delayed treatment reduced the likelihood of TC-CBT initiation (OR=0.93, 95% CI=0.92-0.95). Qualitative studies showed that mental health beliefs (stigma and lack of readiness), provider organizational factors (low availability, privacy issues), and patient lack of time (logistics) were perceived as barriers to initiation by patients and providers.ConclusionsTC-CBT initiation increased among patients who were older and female. Initiation was also higher among providers who had more exposure to TC-CBT in their work environment and when TC-CBT fit into their existing workflow.

Background Posttraumatic stress disorder ( PTSD ) is associated with risk of cardiovascular disease ( CVD ). Biopsychosocial factors associated with PTSD likely account for some or all of this association. We determined whether 1, or a combination of comorbid conditions explained the association between PTSD and incident CVD . Methods and Results Eligible patients used 1 of 5 Veterans Health Affairs medical centers distributed across the United States. Data were obtained from electronic health records. At index date, 2519 Veterans Health Affairs ( VA ) patients, 30 to 70 years of age, had PTSD diagnoses and 1659 did not. Patients had no CVD diagnoses for 12 months before index date. Patients could enter the cohort between 2008 and 2012 with follow-up until 2015. Age-adjusted Cox proportional hazard models were computed before and after adjusting for comorbidities. Patients were middle aged (mean=50.1 years, SD ±11.0), mostly male (87.0%), and 60% were white. The age-adjusted association between PTSD and incident CVD was significant (hazard ratio=1.41; 95% CI : 1.21-1.63). After adjustment for metabolic conditions, the association between PTSD and incident CVD was attenuated but remained significant (hazard ratio=1.23; 95% CI : 1.06-1.44). After additional adjustment for smoking, sleep disorder, substance use disorder, anxiety disorders, and depression, PTSD was not associated with incident CVD (hazard ratio=0.96; 95% CI : 0.81-1.15). Conclusions PTSD is not an independent risk factor for CVD . Physical and psychiatric conditions and smoking that co-occur with PTSD explain why this patient population has an increased risk of CVD . Careful monitoring may limit exposure to CVD risk factors and subsequent incident CVD .

Products of stellar mergers are predicted to be common in stellar populations and can potentially explain stars with peculiar properties. When the merger occurs after the initially more massive star has evolved into the Hertzsprung gap, the merger product may remain in the blue part of the Hertzsprung–Russell diagram for millions of years. Such objects could, therefore, explain the overabundance of observed blue stars, such as blue supergiants. However, it is currently not straightforward to distinguish merger products from genuine single stars or other stars with similar surface diagnostics. In this work, we made detailed asteroseismic comparisons between models of massive post-main-sequence merger products and genuine single stars to identify which asteroseismic diagnostics can be used to distinguish them. In doing so, we developed tools for the relatively young field of merger seismology. Genuine single stars in the Hertzsprung gap are fully radiative, while merger products have a convective He-burning core and convective H-burning shell while occupying similar locations in the Hertzsprung–Russell diagram. These major structural differences are reflected in lower asymptotic period spacing values for merger products and the appearance of deep dips in their period spacing patterns. Our genuine single-star models with masses above roughly 11.4 solar masses develop short-lived intermediate convective zones during their Hertzsprung gap evolution. This also leads to deep dips in their period spacing patterns. Because of the lack of a convective core, merger products and genuine single stars can be distinguished based on their asymptotic period spacing value in this mass range. We performed the comparisons with and without the effects of slow rotation included in the pulsation equations and conclude that the two types of stars are seismically distinguishable in both cases. The observability of the distinguishing asteroseismic features of merger products can now be assessed and exploited in practice. [ABSTRACT FROM AUTHOR]

Introduction: Underrecognition of trauma exposure and PTSD has a significant impact on psychiatric health, physical health, and health behaviors. The purpose of this study is to explore barriers and opportunities for trauma screening in primary care. Methods: Primary care physicians (PCPs) and their patients were interviewed about the acceptability of trauma screening and brief treatment in primary care. Interview transcripts were coded and analyzed for themes using Atlas v. 7.0. Results: Data showed PCPs informally screen for trauma but were hampered by organizational constraints including time, availability of behavioral health providers, and knowledge of trauma-informed-care practices. Most patients with trauma history met with behavioral health providers during their lifetimes, but still did not believe it was the PCPs' role to address trauma exposure, had fears of 'appearing crazy,' or were ambivalent about seeking treatment. Discussion: Findings suggest an enormous complexity involved in screening for trauma in primary care service delivery. Trauma screening appears to work best within the course of relationship building where patients can begin to see that their physician is capable of playing an important role in managing trauma, depression, and PTSD symptoms. We address how trauma discussion can take place within existing trauma informed care guidelines. Keywords: trauma, PTSD, screening.primary care Supplemental materials: https://doi.org/10.1037/fsh0000593.supp, Studies show children exposed to more childhood traumas engage in much riskier health behaviors (namely, alcoholism, drug abuse, depression, suicide attempts, smoking, multiple sexual partners, sexually transmitted infections, physical inactivity, [...]