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Let G be a finite group and let V be a finite and faithful G -module such that V is completely reducible, possibly of mixed characteristic, or V is a G -module over a field of characteristic p with O p (G) = 1. Suppose that M is the largest orbit size in the action of G on V. It is known that the index of the commutator subgroup G ′ in G is bounded by M , that is, | G : G ′ | ≤ M. In this paper, we classify all linear group actions in which | G : G ′ | = M. It turns out that our classification is a vast generalization of a classic 1967 result by D. Passman. We also include an application of the main results to Brauer's k (B) -problem. [ABSTRACT FROM AUTHOR]

We prove that there exists a universal constant D such that if p is a prime divisor of the index of the Fitting subgroup of a finite group G , then the number of conjugacy classes of G is at least $Dp/\log_2p$. We conjecture that we can take $D=1$ and prove that for solvable groups, we can take $D=1/3$. [ABSTRACT FROM AUTHOR]

The prime graph Γ ⁢ (G) of a finite group 퐺 (also known as the Gruenberg–Kegel graph) has as its vertices the prime divisors of | G | , and p ⁢ - ⁢ q is an edge in Γ ⁢ (G) if and only if 퐺 has an element of order p ⁢ q . Since their inception in the 1970s, these graphs have been studied extensively; however, completely classifying the possible prime graphs for larger families of groups remains a difficult problem. For solvable groups, such a classification was found in 2015. In this paper, we go beyond solvable groups for the first time and characterize the prime graphs of a more general class of groups we call pseudo-solvable. These are groups whose composition factors are either cyclic or isomorphic to A 5 . The classification is based on two conditions: the vertices { 2 , 3 , 5 } form a triangle in Γ ̄ ⁢ (G) or { p , 3 , 5 } form a triangle for some prime p ≠ 2 . The ideas developed in this paper also lay the groundwork for future work on classifying and analyzing prime graphs of more general classes of finite groups. [ABSTRACT FROM AUTHOR]

Based on the shell and plate theory, this paper uses the divide-and-combine method (DCM) to derive an analytical out-of-plane compression buckling limit expression of the basic unit of the core layer of a grid beetle elytron plate (GBEP); the accuracy of expression and the mechanism of GBEP unit buckling are investigated through experiments and finite element (FE) simulation. The results show that: (1) the theoretical expression of the out-of-plane compression buckling limit of a GBEP unit obtained by DCM is applicable and is closer to the test results than the classical solution of the out-of-plane compressive buckling of a cylindrical shell and the theoretical result of Flügge. Based on this, a modified expression of the theoretical result of Flügge's compressive buckling limit load is proposed. (2) Given the significant differences between the theoretical values obtained in this paper and the experimental values, the out-of-plane compressive buckling resistance of the GBEP unit and its mechanism are investigated from the viewpoints of structural parameters η (the ratio of the radius of the trabeculae to the width of the element) and deformation process; the synergistic mechanism of the honeycomb-trabeculae structure is also studied. This paper contributes to improving the bionic system derived from the beetle's forewing. [ABSTRACT FROM AUTHOR]

This study investigates how the implementation of program‐level practices by formal youth mentoring programs is associated with the quality of youth mentoring relationships as contexts for youth development and also examines whether this connection is mediated by the mentor‐staff working alliance. Using data from mentors (n = 542) participating in multiple programs (n = 55), multilevel path models examined hypothesized direct and mediated effects. Parallel analyses were conducted with assessments of program practices from staff (n = 219). Greater exposure to program practices was associated with higher ratings of mentoring relationship satisfaction, commitment, and security and lower mentor‐youth relationship negativity. The mentor‐staff working alliance either partially or fully mediated these associations. Staff‐reported practices predicted mentoring relationship satisfaction and commitment without mediation by the working alliance. This study suggests program practices contribute to stronger youth mentoring relationships. The findings also highlight the mentor‐staff working alliance in supporting the development of positive mentoring relationships. [ABSTRACT FROM AUTHOR]

Let ρ(n)$\rho (n)$ denote the maximal number of different primes that may occur in the order of a finite solvable group G, all elements of which have orders divisible by at most n distinct primes. We show that ρ(n)≤5n$\rho (n)\le 5n$ for all n≥1$n\ge 1$. As an application, we improve on a recent bound by Hung and Yang for arbitrary finite groups. [ABSTRACT FROM AUTHOR]

Scheler's impact on Non-conformism points to an affinity between the phenomenology of affectivity and the antibourgeois movement in interwar France. Scheler himself calls on the vitalism of Guyau and Bergson to argue against projective concepts of empathy. He broadens affective situations into an interaction between bourgeois tendencies to narrow ressentiment and generous cultural dynamics. Non-conformists appropriate these modes of affectivity, pried from faith contexts. Jankélévitch transforms Scheler's value ethic into an aggressive virtue ethic. Corbin draws from Scheler the inspiration for a syncretistic anthropology of responsiveness. With reference to Scheler, Aron develops an ethic of value decisions that is free from ressentiment. [ABSTRACT FROM AUTHOR]

Let G be a finite nilpotent group. We prove the following results. (1) If G is of class 2 and acts faithfully and irreducibly on an elementary abelian group V , then all nontrivial orbits of G on V have sizes larger than | G | 1 / 2 . (2) If G ′ is cyclic, then every subgroup of G intersecting trivially with the center of G has order less than | G | 1 / 2 . We also show that a result like (2) cannot be obtained when the hypothesis that G ′ is cyclic is replaced by the hypothesis that the center of G is cyclic. [ABSTRACT FROM AUTHOR]

Let V be a faithful G -module for a finite group G and let p be a prime dividing | G |. An orbit v G for the action of G on V is regular if | v G | = | G : C G (v) | = | G | , and is p -regular if | v G | p = | G : C G (v) | p = | G | p. In this note, we study two questions, one by the authors and one by Isaacs, related to the p -regular orbits and regular orbits of the linear group actions. [ABSTRACT FROM AUTHOR]

Purpose: Recent studies have linked activated spinal glia to neuropathic pain. Here, using a positron emission tomography (PET) scanner with high spatial resolution and sensitivity, we evaluated the feasibility and sensitivity of N,N-diethyl-2-(2-(4-([18F]fluoro)phenyl)-5,7-dimethylpyrazolo[1,5-a] pyrimidin-3-yl)acetamide ([18F]F-DPA) imaging for detecting spinal cord microglial activation after partial sciatic nerve ligation (PSNL) in rats.Procedures: Neuropathic pain was induced in rats (n = 20) by PSNL, and pain sensation tests were conducted before surgery and 3 and 7 days post-injury. On day 7, in vivo PET imaging and ex vivo autoradiography were performed using [18F]F-DPA or [11C]PK11195. Ex vivo biodistribution and PET imaging of the removed spinal cord were carried out with [18F]F-DPA. Sham-operated and PK11195-pretreated animals were also examined.Results: Mechanical allodynia was confirmed in the PSNL rats from day 3 through day 7. Ex vivo autoradiography showed a higher lesion-to-background uptake with [18F]F-DPA compared with [11C]PK11195. Ex vivo PET imaging of the removed spinal cord showed [18F]F-DPA accumulation in the inflammation site, which was immunohistochemically confirmed to coincide with microglia activation. Pretreatment with PK11195 eliminated the uptake. The SUV values of in vivo [18F]F-DPA and [11C]PK11195 PET were not significantly increased in the lesion compared with the reference region, and were fivefold higher than the values obtained from the ex vivo data. Ex vivo biodistribution revealed a twofold higher [18F]F-DPA uptake in the vertebral body compared to that seen in the bone from the skull.Conclusions: [18F]F-DPA aided visualization of the spinal cord inflammation site in PSNL rats on ex vivo autoradiography and was superior to [11C]PK11195. In vivo [18F]F-DPA PET did not allow for visualization of tracer accumulation even using a high-spatial-resolution PET scanner. The main reason for this result was due to insufficient SUVs in the spinal cord region as compared with the background noise, in addition to a spillover from the vertebral body. [ABSTRACT FROM AUTHOR]

If G is permutation group acting on a finite set $\Omega $ , then this action induces a natural action of G on the power set $\mathscr{P}(\Omega)$. The number $s(G)$ of orbits in this action is an important parameter that has been used in bounding numbers of conjugacy classes in finite groups. In this context, $\inf ({\log _2 s(G)}/{\log _2 |G|})$ plays a role, but the precise value of this constant was unknown. We determine it where G runs over all permutation groups not containing any ${{\textrm {A}}}_l, l> 4$ , as a composition factor. [ABSTRACT FROM AUTHOR]

Mechanization has greatly contributed to the success of modern agriculture, with vastly expanded food production capabilities achieved by the higher capacity of farm machinery. However, the increase in capacity has been accompanied by higher vehicle weights that increase risks of subsoil compaction. We show here that while surface contact stresses remained nearly constant over the course of modern mechanization, subsoil stresses have propagated into deeper soil layers and now exceed safe mechanical limits for soil ecological functioning. We developed a global map for delineating subsoil compaction susceptibility based on estimates of mechanization level, mean tractor size, soil texture, and climatic conditions. The alarming trend of chronic subsoil compaction risk over 20% of arable land, with potential loss of productivity, calls for a more stringent design of farm machinery that considers intrinsic subsoil mechanical limits. As the total weight of modern harvesters is now approaching that of the largest animals that walked Earth, the sauropods, a paradox emerges of potential prehistoric subsoil compaction. We hypothesize that unconstrained roaming of sauropods would have had similar adverse effects on land productivity as modern farm vehicles, suggesting that ecological strategies for reducing subsoil compaction, including fixed foraging trails, must have guided these prehistoric giants. [ABSTRACT FROM AUTHOR]

Neutron spin‐echo (NSE) spectroscopy is a powerful tool for the study of magnon lifetimes and magnetic critical dynamics. The unique property of NSE is the energy resolution in the μeV range. The first NSE spectrometers were optimized for quasielastic scattering at small momentum transfers and delivered substantial contributions to the understanding of critical dynamics in ferromagnets and dynamic correlations in spin glasses. The subsequent resonant NSE (NRSE) technique extends the parameter range toward large momentum and energy transfers and permits to measure magnon lifetimes across the Brillouin zone. NRSE also comprises the Larmor diffraction (LD) mode with a resolution for lattice spacings and their variance Δdhkl/dhkl of order 10−6. LD proves useful to determine magnetostriction effects, small lattice distortions related to magnetic ordering, mosaic spread in crystals, and the size distribution of antiferromagnetic domains. Both typical experiments and the related technical innovation are reviewed and an outlook on future developments is given. [ABSTRACT FROM AUTHOR]

Purpose: In this study we compared the recently developed TSPO tracer [18F]F-DPA, with [18F]DPA-714 and [11C]PBR28 by performing in vivo PET imaging on the same Alzheimer's disease mouse model APP/PS1-21 (TG) and wild-type (WT) mice with all three radiotracers. Procedures: To compare the radiotracer uptake, percentage of injected dose/mL (%ID/mL), standardized uptake value ratios to cerebellum (SUVRCB), and voxel-wise analyses were performed. Results: The peak uptake of [18F]F-DPA was higher than 4.3% ID/mL, while [18F]DPA-714 reached just over 3% ID/mL, and [11C]PBR28 was over 4% ID/mL in only one brain region in the WT mice. The peak/60-min uptake ratios of [18F]F-DPA were significantly higher (p < 0.001) than those of [18F]DPA-714 and [11C]PBR28. The differences in [18F]F-DPA SUVRCB between WT and TG mice were highly significant (p < 0.001) in the three studied time periods after injection. [18F]DPA-714 uptake was significantly higher in TG mice starting in the 20–40-min timeframe and increased thereafter, whereas [11C]PBR28 uptake became significant at 10–20 min (p < 0.05). The voxel-wise analysis confirmed the differences between the radiotracers. Conclusions: [18F]F-DPA displays higher brain uptake, higher TG-to-WT SUVRCB ratios, and faster clearance than [18F]DPA-714 and [11C]PBR28, and could prove useful for detecting low levels of inflammation and allow for shorter dynamic PET scans. [ABSTRACT FROM AUTHOR]

A novel methodology to predict the tensile properties of viscoelastic materials as a synergistic function of temperature and loading/displacement rate is presented in this paper. The model is based on the amount of energy dissipated during tensile loading, requiring less input data compared to existing models. The deformation activation energy was measured and accordingly an energy-based temperature shift factor was suggested. Additionally, to describe the material's rate dependency, two new types of energy-based loading/displacement rate shift factors based on the Eyring and Cooperative models were derived. The shift factors were implemented into the theory of viscoelasticity to predict the material tensile behavior at different temperatures and loading/displacement rates. In addition, a new failure criterion was suggested to predict the mechanical strength of the tested materials through the definition of a critical energy level, which determined the maximum energy that a material would be able to dissipate before failure. The model was applied to two different viscoelastic materials; an epoxy adhesive, and an angle-ply glass/epoxy fiber-reinforced polymer (GFRP) composite, two common viscoelastic materials used in the structural and construction industries. To determine the accuracy of the model, the results obtained from the model were compared to the results obtained from experiments. It was observed that the suggested methodology well predicted the stress–strain curves of the tested materials in the linear region and yield stress up to the post-yield region and failure point. In addition, the strength surface of the studied materials, which showed the synchronous effect of temperature and loading/displacement rate on the ultimate tensile strength in a 3-dimensional representation, was introduced. • New energy-based methodology developed to predict viscoelastic tensile properties. • Compared to the existing models, the model required less input data. • Model was applied to an epoxy adhesive and an angle-ply GFRP composite. • Model well-predicted the effects of temperature and rate on the stress–strain curve. • Strength surface was introduced showing temperature and rate effects on strength. [ABSTRACT FROM AUTHOR]

Permanent magnets (PMs) based on manganese show significant potential for applications in electric motors and devices as an alternative to Rare-earth PMs (REPMs). The metastable ferromagnetic τ phase of the Mn-Al system has magnetic performance between the REPM Nd-Fe-B magnets and the lower performance ferrite magnets. However, the maximum performance in Mn-Al PMs has not reached its theoretical limit, in part due to challenges in controlling crystalline defects such as anti-phase boundaries (APBs). APBs act as nucleation sites for domain reversal in Mn-Al and negatively affect magnetization by interrupting the L1 0 ordering, placing Mn atoms into AFM-coupled Mn-Mn configurations. In this study, Ab-initio modeling was used to screen ternary elements based on their affinity to segregate to the APB and on their preference for FM configuration. The ternary element addition of 1 at.% Ti lowered the density of APBs as observed in a transmission electron microscope. The 1 at.% Ti addition was observed to improve (BH) max over the base alloy, by preserving H ci and improving M r. It also significantly increased the fraction of twin boundaries in the τ phase. AFM behavior that was observed in the base alloy during T C heating experiments (Néel behavior) and high-field VSM measurements (spin-flop behavior) was effectively suppressed with the addition of Ti. Additionally, the Ti addition thermally stabilized H ci at 550 °C, improving τ phase processability. Other candidate elements, Cr, V, and Zr, were modeled to have similar potential for minimizing APBs when added to Mn-Al. [Display omitted] [ABSTRACT FROM AUTHOR]

Soil compaction by farm machinery may persist for decades, hampering soil productivity and functioning. Assessing compaction costs and guiding recovery strategies are hindered by paucity of data on soil structure recovery rates. A long‐term Soil Structure Observatory was established on a loamy soil in Switzerland to monitor soil structure recovery after prescribed compaction, and to better assess the roles of natural processes (vegetation, macrofauna, and shrink–swell cycles) on recovery patterns. The aim of this study was to quantify short‐term soil structure recovery under natural conditions in the presence and absence of plant cover (ley and bare soil). We measured soil porosity and gas and water transport capabilities at 0.1 and 0.3 m depth. Two years after the compaction event, soil physical properties have not recovered to precompaction levels, even within the topsoil. Surprisingly, no differences were observed in the recovery patterns of ley and bare soil treatments. Measurements show that recovery rates differ among soil properties with the most severely affected properties by compaction (permeability) exhibiting highest recovery rates. Total soil porosity shows no recovery trend, suggesting lack of soil decompaction. Improved soil functions and decompaction are distinct aspects of soil structure recovery, with the latter requiring net upward transport of soil mass. We suggest that soil structure recovery proceeds at two fronts: from the soil surface downward, and expanding around local biologically‐active pockets (marked by biopores) into the compacted soil volumes. This concept could be tested with additional data of longer time series at our site as well as in other soils and climates. Core Ideas: Soil physical properties have not recovered to precompaction values within 2 yr.Recovery rates vary among soil physical properties.Decompaction (increase in total porosity) requires upward transport of soil mass.Functional recovery such as improved permeability does not require decompaction.A concept for soil structure recovery patterns is proposed. [ABSTRACT FROM AUTHOR]

Background: Many malignant tumours have increased TSPO expression, which has been related to a poor prognosis. TSPO-PET tracers have not comprehensively been evaluated in peripherally located tumours. This study aimed to evaluate whether N,N-diethyl-2-(2-(4-([18F]fluoro)phenyl)-5,7-dimethylpyrazolo[1,5-a]pyrimidin-3-yl)acetamide ([18F]F-DPA) can reflect radiotherapy (RT)-induced changes in TSPO activity in head and neck squamous cell carcinoma (HNSCC). Methods: RT was used to induce inflammatory responses in HNSCC xenografts and cells. [18F]F-DPA uptake was measured in vivo in non-irradiated and irradiated tumours, followed by ex vivo biodistribution, autoradiography, and radiometabolite analysis. In vitro studies were performed in parental and TSPO-silenced (TSPO siRNA) cells. TSPO protein and mRNA expression, as well as tumour-associated macrophages (TAMs), were also assessed. Results: In vivo imaging and ex vivo measurement revealed significantly higher [18F]F-DPA uptake in irradiated, compared to non-irradiated tumours. In vitro labelling studies with cells confirmed this finding, whereas no effect of RT on [18F]F-DPA uptake was detected in TSPO siRNA cells. Radiometabolite analysis showed that the amount of unchanged [18F]F-DPA in tumours was 95%, also after irradiation. PK11195 pre-treatment reduced the tumour-to-blood ratio of [18F]F-DPA by 73% in xenografts and by 88% in cells. TSPO protein and mRNA levels increased after RT, but were highly variable. The proportion of M1/M2 TAMs decreased after RT, whereas the proportion of monocytes and migratory monocytes/macrophages increased. Conclusions: [18F]F-DPA can detect changes in TSPO expression levels after RT in HNSCC, which does not seem to reflect inflammation. Further studies are however needed to clarify the physiological mechanisms regulated by TSPO after RT. [ABSTRACT FROM AUTHOR]

Human influences on natural environments are now ubiquitous but manifest in multiple and unique ways depending on local environments and communities. Attempts to control, or mediate, local pests to residences or to agriculture can impart important negative consequences on systems. Secondary exposure to anticoagulant rodenticides (ARs) can cause numerous adverse effects on wild carnivores including death. Few studies have quantified AR prevalence, investigated their pathway of exposure, or associations with specific location types in the northeastern U.S. We hypothesized that ARs would be found in the mesocarnivore community throughout Pennsylvania and have the greatest detection rate in highly urbanized or agricultural landscapes. From 2019 through early 2022, we collected carcasses to obtain liver samples (n = 265) from three species of carnivores: bobcats (Lynx rufus (Schreber, 1777)), fishers (Pekania pennanti (Erxleben, 1777)), and river otters (Lontra canadensis (Schreber, 1777)). We used generalized linear models to test for differences in AR detection rates among species and spatial scales including the six Pennsylvania Game Commission regions and 23 wildlife management units. We detected ARs in all species (44.2% collectively), but detection rates differed among species. Our study is the first to document ARs within North American river otters. [ABSTRACT FROM AUTHOR]

Scant empirical attention has been devoted to understanding endings in youth mentoring relationships, despite the frequency with which they occur. This study examined data from a mixed‐methods study of mentoring relationship endings in which youth mentees, the youth's parents or guardians, mentors, and program staff were surveyed about the closure process, and a subsample of program staff, mentors, and parents or guardians also participated in in‐depth qualitative interviews. Findings from a descriptive analysis detailing the perceptions of multiple stakeholders in the closure process as reported in surveys are presented along with case studies derived from a case‐based analysis of in‐depth qualitative interview data. Most relationship endings were initiated by the mentors, and although some matches engaged in an intentional and direct closure process, more often the endings were unclear or even confusing to program participants. Implications for practice are discussed, including recommendations for more training and greater involvement of program staff in the closure process, as are implications for future research. [ABSTRACT FROM AUTHOR]

In many mentoring programs, mentor–youth pairs have the latitude to engage in a wide range of activities together across varying community settings. Within this context, program staff are tasked with supporting development of high‐quality relationships between mentors and youth. To date, however, this role of program staff has been largely overlooked in research. The current study investigates potential contributions of program staff to mentoring relationships in the Big Brothers Big Sisters community‐based mentoring program over their first 15 months of relationship development with a sample of 450 mentor–youth pairs that were supported by 76 program staff across 10 agencies. Two‐level analyses (mentoring relationships nested within program staff) examined characteristics and approaches of program staff as prospective predictors of several facets of mentoring relationship quality as reported by youth: closeness, help with coping, youth‐centeredness, growth orientation, and attachment. Staff‐reported work engagement and emphasis on adherence to program guidelines as well as supervisor‐rated staff competence predicted more favorable mentoring relationship quality. By contrast, a nondirective approach to supporting mentors, as reported by staff, predicted lower relationship quality. These findings suggest that further investigation of program staff influences on mentoring relationship development could be fruitful and ultimately provide a basis for enhancing program effectiveness. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ε to τ phase transformation was studied in-situ using XRD, DSC, and T-VSM. • DFT and DSC concurred that the ε to ε' to τ pathway is energetically favorable. • Annealing ε at 350 °C showed ε' is ferromagnetic, in agreement with DFT. • A boundary front of ε' was observed between the τ and ε phases at 350 °C. • The ε to ε' to τ path has lower activation energies than ε to τ, kinetic advantage. Rare-earth-free permanent magnet materials based on Mn show great promise for applications in electric motors and devices. The metastable ferromagnetic τ phase of the Mn-Al system has magnetic properties between those of the high-performance Nd-Fe-B magnets and the lower-performance ferrite magnets. However, the hybrid displacive-diffusional pathway of τ formation, from the parent ε phase through the intermediary ε' phase, is still not fully understood. This phase transformation progression was studied in-situ using diffractive, calorimetric, and magnetometric techniques to show that the progression from ε to τ in Mn 54 Al 46 at <450 °C involves the ordering of ε into ε'. Density functional theory calculations were performed on each phase and confirmed the experimental observation that the ε to ε' to τ pathway is energetically favorable. Isothermal annealing of quenched-in ε at 350 °C demonstrated that ε' is ferromagnetic, also in agreement with theoretical results, with a moderate coercivity of at least 50 kA/m. The τ phase was observed to nucleate along the prior ε phase grain boundaries and grow into the ε' phase regions. A boundary front of ε' was observed between the τ and ε phases. Both Kissinger and Flynn-Wall-Ozawa methods were used to determine the activation energies for the ε' and τ phase transformations with values of ∼140 kJ/mol obtained for both phases. Therefore, the ordering transformation to ε' and the hybrid displacive-diffusional transformation to τ were shown to overcome the same magnitude energy barrier. Both activation energies were less than previous τ phase activation energies measured on Mn 55 Al 45 in the absence of a significant ε' ordering exotherm, providing a kinetic benefit to the ε to ε' to τ pathway at 350 °C. The results of this study give insight into the phase transformation of L1 0 binary materials as well as materials that undergo a disorder–order transformation followed by displacive shear. [ABSTRACT FROM AUTHOR]

Information on how crop yields are affected by weather variations and extreme weather is needed to develop climate adaptation measures for arable cropping systems. Here, we analysed the effects of weather anomalies and soil texture on crop yield anomalies across Sweden from 1965 to 2020. The aims of this study were to (i) assess the effects of temperature and precipitation anomalies and extreme weather on crop yield anomalies for major field crops across Sweden, (ii) quantify how crop responses to weather anomalies vary along the north-south climate gradient across Sweden, and (iii) elucidate the impacts of soil texture on yield responses to weather anomalies. We used daily mean air temperature, daily total precipitation, soil texture and crop yield data from public databases covering all 21 counties in Sweden. Yield data was detrended to account for the effects of agricultural intensification on crop productivity. To assess seasonal weather influences on crop yields, temporal trends of daily average temperature and daily total precipitation were detrended for each season containing a three-month period. We also used a water balance index and a heat wave index to evaluate the impact of extreme weather. Our analyses showed that years with extreme weather during summer (i.e. heat waves, drought or water excess) resulted in the largest negative yield anomalies. Spring-sown crops were more negatively affected by extreme weather compared to autumn-sown crops, which we associate with differences in the lengths of the growth period for autumn- and spring-sown crops. Effects of soil texture on yield anomalies were found for spring-sown cereals, where negative effects of drought were exacerbated with increasing sand content. Moreover, we showed that the effects of weather conditions on crop yield anomalies differed between different regions within the country. In northern Sweden, crop yields were more sensitive to excess water, while drought effects were more pronounced in southern Sweden. Similarly, increased summer temperatures favoured crop yields in northern Sweden but had a negative impact on crop yields in the southern part of the country. Our study demonstrates that weather impacts on yields vary between crops and locations, and that adaptation to future climate will require crop- and site-specific strategies. [Display omitted] • The impacts of seasonal weather anomalies and soil texture on crop yields were assessed in this study. • Years with extreme weather during summer resulted in the largest average yield losses. • Spring-sown crops were more negatively affected by extreme weather than autumn-sown crops. • Strategies for adapting crop production to future climate must consider differences between crop species and locations. [ABSTRACT FROM AUTHOR]

Accurate modelling of porous aggregate rupture is critical when simulating natural phenomena involving material fragmentation and seeking to improve technological processes. For this, numerical models based on the discrete element method must be parameterised, which is a challenging task. It is even more challenging in the case of scale-variant materials, e.g. agricultural soils. In numerical simulations based on theoretical considerations, we identified a linear correlation between friability and fractal dimension for porous aggregates, with particle bond strength defining the rate at which friability coefficient diminished with fractal increment. By combining numerical simulation results with laboratory measurements, we established a unique use for friability as a material macro property to determine particle bond strength and density for different aggregate sizes. This allows parameterisation of discrete element models to simulate how tensile strength varies as a function of aggregate size. Unlabelled Image • The numerical approach shows linear correlation for friability and fractal dimension. • Particle bond strength governs the rate of friability decrement as fractal increases. • Friability parameterises DEM model to reproduce the scale effect of aggregate rupture. [ABSTRACT FROM AUTHOR]

Highly committed mentors may be less likely to end their mentoring relationships with their mentees. Theory suggests commitment is predicted by relationship satisfaction, investment, and perceptions of available alternatives. Mentoring program practices may influence commitment, but little research has investigated potential mechanisms. Using data from 537 mentors representing 55 mentoring programs, this study examined a theoretical path model in which mentor perceptions of program practices, specifically setting expectations, prematch mentor training, and matching based on mentor preferences, predict mentor satisfaction, investment, perceptions of available alternatives, and ultimately, relationship commitment. As expected, commitment was associated positively with satisfaction and investment and negatively with available alternatives. Perceptions of the program setting clear expectations, the amount of prematch training, and matching by preferences predicted mentor commitment. These associations were mediated by relationship satisfaction, investment, and available alternatives, respectively. These findings identify program practices that can support mentor commitment. [ABSTRACT FROM AUTHOR]

Background: Although inhaled therapy reduces exacerbations among patients with COPD, the effectiveness of providing inhaled treatment per risk stratification models remains unclear.Research Question: Are inhaled regimens that align with the 2017 Global Initiative for Chronic Obstructive Lung Disease (GOLD) strategy associated with clinically important outcomes?Study Design and Methods: We conducted secondary analyses of Long-term Oxygen Treatment Trial (LOTT) data. The trial enrolled patients with COPD with moderate resting or exertional hypoxemia between 2009 and 2015. Our exposure was the patient-reported inhaled regimen at enrollment, categorized as either aligning with, undertreating, or potentially overtreating per the 2017 GOLD strategy. Our primary composite outcome was time to death or first hospitalization for COPD. Additional outcomes included individual components of the composite outcome and time to first exacerbation. We generated multivariable Cox proportional hazard models across strata of GOLD-predicted exacerbation risk (high vs low) to estimate between-group hazard ratios for time to event outcomes. We adjusted models a priori for potential confounders, clustered by site.Results: The trial enrolled 738 patients (73.4% men; mean age, 68.8 years). Of the patients, 571 (77.4%) were low risk for future exacerbations. Of the patients, 233 (31.6%) reported regimens aligning with GOLD recommendations; most regimens (54.1%) potentially overtreated. During a 2.3-year median follow-up, 332 patients (44.9%) experienced the composite outcome. We found no difference in time to composite outcome or death among patients reporting regimens aligning with recommendations compared with undertreated patients. Among patients at low risk, potential overtreatment was associated with higher exacerbation risk (hazard ratio, 1.42; 95% CI, 1.09-1.87), whereas inhaled corticosteroid treatment was associated with 64% higher risk of pneumonia (incidence rate ratio, 1.64; 95% CI, 1.01-2.66).Interpretation: Among patients with COPD with moderate hypoxemia, we found no difference in clinical outcomes between inhaled regimens aligning with the 2017 GOLD strategy compared with those that were undertreated. These findings suggest the need to reevaluate the effectiveness of risk stratification model-based inhaled treatment strategies. [ABSTRACT FROM AUTHOR]

Here, we describe the development of an in‐house‐built device for the fully automated multistep synthesis of the cannabinoid CB1 receptor imaging tracer (3R,5R)‐5‐(3‐([18F]fluoromethoxy‐d2)phenyl)‐3‐(((R)‐1‐phenylethyl)amino)‐1‐(4‐(trifluoromethyl)phenyl)pyrrolidin‐2‐one ([18F]FMPEP‐d2), following good manufacturing practices. The device is interfaced to a HPLC and a sterile filtration unit in a clean room hot cell. The synthesis involves the nucleophilic 18F‐fluorination of an alkylating agent and its GC purification, the subsequent 18F‐fluoroalkylation of a precursor molecule, the semipreparative HPLC purification of the 18F‐fluoroalkylated product, and its formulation for injection. We have optimized the duration and temperature of the 18F‐fluoroalkylation reaction and addressed the radiochemical stability of the formulated product. During the past 5 years (2013–2018), we have performed a total of 149 syntheses for clinical use with a 90% success rate. The activity yield of the formulated product has been 1.0 ± 0.4 GBq starting from 11 ± 2 GBq and the molar activity 600 ± 300 GBq/μmol at the end of synthesis. [ABSTRACT FROM AUTHOR]

[18F]F-DPA, a novel translocator protein 18 kDa (TSPO)-specific radioligand for imaging neuroinflammation, has to date been synthesized with low to moderate molar activities (Am's). In certain cases, low Am can skew the estimation of specific binding. The high proportion of the non-radioactive component can reduce the apparent-specific binding by competitively binding to receptors. We developed a nucleophilic synthesis of [18F]F-DPA resulting in high Am (990 ± 150 GBq/µmol) and performed in vivo comparison with low Am (9.0 ± 2.9 GBq/µmol) [18F]F-DPA in the same APP/PS1-21 and wild-type mice (injected masses: 0.34 ± 0.13 µg/kg and 38 ± 15 µg/kg, respectively). The high level of microgliosis in the APP/PS1-21 mouse model enables good differentiation between diseased and healthy animals and serves better to distinguish the effect of differing Am on specific binding. The differing injected masses affect the washout profile and shape of the time–activity curves. Ratios of standardized uptake values obtained with high and low Am [18F]F-DPA demonstrate that there is a 1.5-fold higher uptake of radioactivity in the brains of APP/PS1-21 animals when imaging is carried out with high Am [18F]F-DPA. The differences between APP/PS1-21 and wild-type animals showed higher significance when high Am was used. [ABSTRACT FROM AUTHOR]

Many young people experience social isolation and loneliness, which can have adverse effects on physical and psychological well-being. We propose that intergenerational relationships created through formal youth mentoring programs have the potential to reduce the social isolation of young people. Mentoring programs also enable adult volunteers to form new interpersonal connections. In addition, mentoring offers the possibility of strengthening the fabric of communities through engagement and interaction among participants from different social, racial, and economic backgrounds. Mentoring program goals, often influenced by sponsor priorities, rarely focus specifically on reducing social isolation and promoting human connections as primary outcomes, but shifting to this emphasis could promote greater attention to relational practice that prioritizes the inherent value of the mentoring relationship itself. Given the long history and widespread popularity of formal youth mentoring, we suggest the field offers practice expertise, research knowledge, and organizational infrastructure as a foundation for addressing social isolation among young people. However, we also caution that youth mentoring, as a relationship-based intervention, poses potential risks if not implemented well. Issues concerning power, ethics, and social justice need to be made explicit to ensure the support of intergenerational relationships that reduce rather than reproduce social patterns of oppression, stigmatization, and inequality. [ABSTRACT FROM AUTHOR]

A hitherto unrecognized resolution effect in neutron Larmor diffraction (LD) is reported, resulting from small‐angle neutron scattering (SANS) in the sample. Small distortions of the neutron trajectories by SANS give rise to a blurring of the Bragg angles of the order of a few hundredths of a degree, leading to a degradation of the momentum resolution. This effect is negligible for single crystals but may be significant for polycrystalline or powder samples. A procedure is presented to correct the LD data for the parasitic SANS. The latter is accurately determined by the SESANS technique (spin–echo small‐angle neutron scattering), which is readily available on Larmor diffractometers. The analysis technique is demonstrated on LD and SESANS data from α‐Fe2O3 powder samples. The resulting d‐spacing range agrees with experimental data from high‐resolution synchrotron radiation powder diffraction on the same sample. [ABSTRACT FROM AUTHOR]

Purpose: The α2-adrenoceptors mediate many effects of norepinephrine and epinephrine, and participate in the regulation of neuronal, endocrine, cardiovascular, vegetative, and metabolic functions. Of the three receptor subtypes, only α2A and α2C are found in the brain in significant amounts. Subtype-selective positron emission tomography (PET) imaging of α2-adrenoceptors has been limited to the α2C subtype. Here, we report the synthesis of 6-[18F]fluoro-marsanidine, a subtype-selective PET tracer candidate for α2A-adrenoceptors, and its preclinical evaluation in rats and mice. Procedures: 6-[18F]Fluoro-marsanidine was synthesized using electrophilic F-18 fluorination with [18F]Selectfluor bis(triflate). The tracer was evaluated in Sprague Dawley rats and in α2A-knockout (KO) and wild-type (WT) mice for subtype selectivity. In vivo PET imaging and ex vivo brain autoradiography were performed to determine the tracer distribution in the brain. The specificity of the tracer for the target was determined by pretreatment with the subtype-non-selective α2-agonist medetomidine. The peripheral biodistribution and extent of metabolism of 6-[18F]fluoro-marsanidine were also analyzed. Results: 6-[18F]Fluoro-marsanidine was synthesized with [18F]Selectfluor bis(triflate) in a radiochemical yield of 6.4 ± 1.7 %. The molar activity was 3.1 to 26.6 GBq/μmol, and the radiochemical purity was > 99 %. In vivo studies in mice revealed lower uptake in the brains of α2A-KO mice compared to WT mice. The results for selectivity were confirmed by ex vivo brain autoradiography. Blocking studies revealed reduced uptake in α2A-adrenoceptor-rich brain regions in pretreated animals, demonstrating the specificity of the tracer. Metabolite analyses revealed very rapid metabolism of 6-[18F]fluoro-marsanidine with blood-brain barrier-permeable metabolites in both rats and mice. Conclusion: 6-[18F]Fluoro-marsanidine was synthesized and evaluated as a PET tracer candidate for brain α2A-adrenoceptors. However, rapid metabolism, extensive presence of labeled metabolites in the brain, and high non-specific uptake in mouse and rat brain make 6-[18F]fluoro-marsanidine unsuitable for α2A-adrenoceptor targeting in rodents in vivo. [ABSTRACT FROM AUTHOR]

• Stress ratio effect on fatigue behavior of (±45) 2s GFRP laminate was investigated. • Fiber realignment increases stiffness compensating decrease from fatigue damage. • S-N curve was steeper for R = 0.1, while scatter was higher under R = 0.5. The effect of the stress ratio (R = σ min /σ max) on the fatigue behavior of (±45) 2S angle-ply glass/epoxy composite laminates was investigated by comparing their mechanical, thermal, and optical properties under the stress ratio of 0.5 with previous fatigue results obtained under the stress ratio of 0.1. When the stress ratio was increased from 0.1 to 0.5, the fatigue life was enhanced at the same σ max and the slope of S-N curve decreased, exhibiting more scattered responses. In addition, as the stress ratio increased, the fatigue damage was distributed more uniformly with a lower self-generated temperature at the same σ max. At R = 0.5, fiber realignment, due to cyclic creep, increased the fatigue stiffness, thus compensating the decreasing effect of fatigue damage. At high stress levels, the stiffening effect dominated the stiffness evolution, resulting in greater fatigue stiffness with an increasing number of fatigue cycles; however, at low stress levels the degrading effect due to fatigue damage was prevalent. The stiffening effect led to smaller hysteresis loop areas at the beginning of the fatigue experiments, which subsequently stabilized for the greater part of the specimen fatigue life, followed by a slight increase before failure. At R = 0.1, the fatigue stiffness decreased further and the hysteresis loop area became larger at all stress levels at the same σ max since the stiffening effect was less and fatigue damage more severe. [ABSTRACT FROM AUTHOR]

Reducing greenhouse gas emissions from arable soil while maintaining productivity is a major challenge for agriculture. Biochar is known to reduce N2O emissions from soil, but the underlying mechanisms are unclear. This study examined the impact of green waste biochar (20 Mg ha−1) and lime (CaCO3; 2 Mg ha−1) application on soil gas transport properties and related changes in these to soil N2O and CO2 emissions measured using automated chambers in a field experiment cropped with maize. In situ soil water content monitoring was combined with laboratory measurements of relative soil gas diffusion coefficient (Dp/D0) at different matric potentials, to determine changes in Dp/D0 over time. Cumulative N2O emissions were similar in the control and lime treatment, but much lower in the biochar treatment. Cumulative CO2 emissions decreased in the order: lime treatment > biochar treatment > control soil. When N2O emissions were not driven by excess N supply shortly after fertilisation, they were associated with Dp/D0 changes, whereby decreases in Dp/D0 corresponded to N2O emissions peaks. No distinct pattern was observed between CO2 emissions and Dp/D0. Cumulative N2O emissions were positively related to number of days with Dp/D0 < 0.02, a critical limit for soil aeration. These results indicate that improved soil gas diffusivity, and hence improved soil aeration, may explain the effect of biochar in reducing N2O emissions. They also suggest that knowledge of Dp/D0 changes may be key to explaining N2O emissions. [ABSTRACT FROM AUTHOR]

• Limited resource accessibility reduces crop productivity on compacted soil. • Plants grown on compacted soil are exposed to a multi-stress environment. • A plant eco-physiological perspective is needed to develop mitigation strategies. • Improving tolerance to specific stresses through breeding enhances crop performance. • Restoring specific soil properties facilitates root growth and resource accessibility. Soil compaction constitutes a major threat to the fertility of arable soils and food security. The aim of this paper is to highlight the need and opportunities for plant eco-physiological approaches to identify strategies to recover crop yields after soil compaction. Reduced productivity on compacted soil primarily results from decreased root elongation rates and thus limited accessibility to water and nutrients. Hence, strategies to recover productivity after compaction must address plant eco-physiological phenomena that underlie low root system expansion rates. In compacted soil, root growth is decreased due to high soil penetration resistance and due to low oxygen concentration in soil air caused by reduced fluid transport capability. Thus, plant roots are exposed to a multi-stress environment, which needs to be addressed directly when aiming to recover productivity after compaction in the long-term. Here, we discuss possibilities to increase root growth in order to enhance resource accessibility and recover crop productivity on compacted soil. Yield recovery can be achieved through breeding of novel cultivars and targeted soil management approaches. On the one hand, the tolerance of plants to the different soil physical stresses can be enhanced by selecting for specific root traits that facilitate root growth in compacted soil. Soil management approaches that improve specific physical properties of compacted soil on the other hand can facilitate root growth in compacted soil. Since plant roots are major drivers of soil structure dynamics, increasing root growth in compacted soil may not only mitigate crop productivity losses but also recover soil structure. [ABSTRACT FROM AUTHOR]

Origami offers a novel design possibility for periodic sandwich cores. The curved-crease origami is adopted to enhance the anti-buckling performance and reduce the abrupt change of the carbon fibers in the origami sandwich cores. CFRP curved-crease origami sandwich structures were fabricated using a hot press molding method. Analytical models were developed for predicting the shear stiffness and strength concerning different failure modes including debonding, compressive and shear buckling, tensile, compressive and shear fracture in both transverse and longitudinal directions. The shear deformation histories, failure modes, strength and stiffness of the sandwich structures were investigated through experiments and finite element analysis (FEA). The analytical models, experiments, and simulations agree with each other reasonably. The origami sandwich undergoes buckling failure when the wall thickness of the origami core is sufficiently thin. With the increase of the wall thickness, debonding between the face sheets and the origami cores usually occurs instead of fracture. The exploration of the shear behaviors lays the foundation for the applications of the origami sandwich structures in the lightweight construction fields. [ABSTRACT FROM AUTHOR]

Highlights • Creep-fatigue interaction in (±45) 2s glass/epoxy composite laminates was studied. • Fatigue loading was interrupted by creep at the maximum stress level. • Fatigue behavior was affected by hold loads (creep). • Damage was observed at the early stages of pure creep. • Fatigue damage accelerated the creep strain development during the hold time. Abstract Angle-ply (±45) 2S glass/epoxy composite specimens have been subjected to pure creep and tension-tension constant amplitude fatigue loading interrupted at σ max by creep intervals lasting for 2 or 48 h in order to examine the effects of creep loading on the fatigue response and vice versa. The specimens' behavior and damage status were continuously monitored during the experiments; strains were measured by a video extensometer, the self-generated temperature on the specimens' surface was recorded by an infrared camera, while a digital camera with sufficient backlighting was used in order to capture the damage development in the translucent specimens throughout the experiment. Post-mortem photos were taken by a digital microscope for the analysis of the fracture surfaces. In comparison to continuous fatigue, applying the creep-fatigue loading pattern with a 2-h creep time at low stress levels had no effect on fatigue life. However, as the stress level increased, specimen stiffening occurred during creep loading because of the glass fiber realignment, which also decreased the internal friction, hysteresis loop area, and self-generated temperature, thus prolonging the fatigue life. The restoring of fatigue stiffness was greater at a creep time of 48 h due to more creep strain, which led to more fiber realignment. However, the higher creep strain at high stress levels caused more creep damage and thus resulted in a shorter fatigue life. In addition, it was observed that the fatigue damage accelerated creep deformation. [ABSTRACT FROM AUTHOR]

Highlights • Confined soil compression test is affected by soil-cylinder wall friction. • Friction impact the stress field and the bulk density within the sample. • Overall soil displacement is reduced affecting final bulk density. • The effects are governed by sample dimension and cannot be neglected unless sample diameter to height ratios > 8. • Poisson's ratio affects the radial to vertical stress ratio. Abstract Compressive properties of arable and forest soils are typically derived from data obtained in uniaxial confined compression tests. However, the stress field, final state of compression and thus compressive properties derived from such tests are dependent on sample dimensions, soil-cylinder wall friction and soil material properties. In this study, we analysed the stress field and bulk density distribution within a cylindrical soil sample under uniaxial compression, and how these are affected by sample dimension, soil-cylinder wall friction and elastic properties of soil. For this, we modelled a uniaxial compression test using the finite element method (FEM) and performed simulations for a range of sample diameter to height ratios (D/h), different values of soil-wall friction coefficient (μ) and different soil elastic properties (Young's modulus and Poisson's ratio). We use experimental data to validate the findings. The results showed a high impact of soil-cylinder wall friction on the stress field within the sample. This resulted in stress concentration at the top of sample edges (walls) and decreasing stresses at the bottom of the sample. However, the relative impact of soil-wall friction on sample average behaviour decreased with increasing D / h. These results suggest that the effect of soil-wall friction on sample-average bulk density cannot be neglected unless D / h >8. Correction of bulk density for μ and D / h could be a practical way to compare data obtained in laboratories using different sample sizes. [ABSTRACT FROM AUTHOR]

[18F]NS12137 (exo‐3‐[(6‐[18F]fluoro‐2‐pyridyl)oxy]8‐azabicyclo[3.2.1]octane) is a highly selective norepinephrine transporter (NET) tracer. NETs are responsible for the reuptake of norepinephrine and dopamine and are linked to several neurodegenerative and neuropsychiatric disorders. The aim of this study was to develop a copper‐mediated 18F‐fluorination method for the production of [18F]NS12137 with straightforward synthesis conditions and high radiochemical yield and molar activity. [18F]NS12137 was produced in two steps. Radiofluorination of [18F]NS12137 was performed via a copper‐mediated pathway starting with a stannane precursor and using [18F]F− as the source of the fluorine‐18 isotope. Deprotection was performed via acid hydrolysis. The radiofluorination reaction was nearly quantitative as was the deprotection based on HPLC analysis. The radiochemical yield of the synthesis was 15.1 ± 0.5%. Molar activity of [18F]NS12137 was up to 300 GBq/μmol. The synthesis procedure is straightforward and can easily be automated and adapted for clinical production. [ABSTRACT FROM AUTHOR]

We have successfully electrospun un-sulfonated fibers of poly(ether ether ketone), PEEK, from the molten state at 350 °C. Unlike solution electrospinning of PEEK, which produces sulfonated fibers with reduced thermal stability, melt electrospinning produces chemically unaltered PEEK fibers. These fibers are smooth, defect-free, and round in cross-section. Most fiber diameters range from 1.5 μm to 8.5 μm. A large interstitial fiber with diameter reaching up to 100 μm is occasionally deposited at the end of the spin. As-spun oriented amorphous fibers, having diameters less than 10 μm, were selected for fast scanning calorimetric studies of the glass transition and melting behavior. Dynamic fragilities of melt electrospun oriented amorphous PEEK fibers and amorphous PEEK quenched from the molten state, were evaluated according to Moynihan's method of cooling at variable rates then reheating at a fixed rate and were found to be 200 ± 5 and 150 ± 5, respectively. These results suggest that orientation in the amorphous state of electrospun fibers plays a role in the dynamics of glass formation. Image 1 • We successfully electrospun poly (ether ether ketone), PEEK, fibers from the melt. • As spun fibers are chemically the same as native PEEK, and are non-crystalline. • Fast scanning calorimetry was used to cool fibers over a wide range of rates. • PEEK fibers shrink above T g but maintain some orientational birefringence. • Dynamic fragility of fibers is greater than that of melt-cooled PEEK. [ABSTRACT FROM AUTHOR]

Abstract Clay is a basic soil constituent that governs many soil properties including pore characteristics, which in turn control a range of crucial soil properties and functions. This study explored the relationships between aggregate strength and soil pore structure characteristics for a range of clay contents along a natural gradient, and investigated the influence of clay content and matric potential on soil workability. Soil samples (100 cm3 soil cores and bulk soil) were sampled from the 5–15 cm depth in four locations in an arable field near Lerbjerg, Denmark, which ranged in clay content from 0.119 to 0.446 kg kg−1. The soil cores were drained to five matric potentials in the range −10 to −1000 hPa to obtain volumetric water content and air-filled porosity (ε a). We measured air permeability and gas diffusivity and calculated tortuosity (τ) and pore organization at −100 hPa. Soil aggregates were obtained from the bulk soil and their tensile strength (Y) and specific rupture energy (E sp) were determined at −100, −300, −1000 hPa and at air-dry state. Y and E sp increased with decreasing matric potential and with increasing clay content, which consequently affected soil workability. ε a at −100 hPa or air-filled macroporosity were negatively related to Y and E sp , and positively to the range of water contents for tillage (Δ θ RANGE). This indicates the importance of air-filled macroporosity for soil crumbling during tillage. The findings of the study suggest that management practices that increase soil macroporosity can potentially decrease aggregate strength and increase Δ θ RANGE and hence improve soil workability. We suggest that in fields with highly variable soils operations should be scheduled at periods when the range of water contents for tillage are suitable for the whole field to reduce the risk of soil structural damage induced by tillage. Highlights • Air-filled porosity decreased with increasing clay content at −100, −300 and −1000 hPa. • Aggregate strength increased with decreasing matric potential and with increasing clay content. • We found a strong positive relationship between aggregate strength and air-filled macroporosity. • The range of water contents for tillage decreased with increasing clay content. [ABSTRACT FROM AUTHOR]

Background: In 2011 the Knee Society Score (KSS) was revised to include patient expectations, satisfaction, and physical activities as patient-reported outcomes. Since the new KSS has become a widely used method to evaluate patient status after TKA, we sought to translate and validate it for German-speaking populations.Questions/purposes: After translation of the new KSS into German using established guidelines, we sought to test the new German version for (1) validity; (2) responsiveness; and (3) reliability.Methods: The new KSS form was translated and adapted according to the available guidelines. The final version was used to validate the German version of the new KSS (GNKSS) in 133 patients undergoing TKA, of which 100 patients were included in the study as per inclusion criteria. Patients completed the GNKSS form along with the German WOMAC and the German SF-36 scores preoperatively and at the 2-year postoperative followup. Construct validity was tested by comparing domain scores of the GNKSS with domain scores of the German WOMAC and the SF-36. Responsiveness was evaluated by comparing pre- and postoperative scores in all questionnaires in all patients using standardized response means. To evaluate reliability, every second patient (n = 50) in the whole group was asked to complete the GNKSS form a second time 1 week after their 2-year followup; 39 patients responded. This sample group was considered representative after testing the difference among age, sex, body mass index, operation side, preoperative or postoperative GNKSS, and WOMAC scores with the original group. Intraclass correlation coefficients (ICCs) were used to assess reliability and Cronbach's α was an indicator of internal consistency of each domain score.Results: Construct validity was excellent pre- and postoperatively between the GNKSS and the WOMAC for domains including symptoms, satisfaction, total functional score, and total score and activity subdomains, except the expectation domain and advanced and discretionary subdomains of the GNKSS and the stiffness domain of WOMAC. The expectation domain showed either no significant correlation or only weak correlations with the domains of WOMAC pre- as well as postoperatively (r ranging between -0.19 and -0.34). Correlation of the function section of the GNKSS as well as the physical function and role-physical domains of the SF-36 pre- and postoperatively were moderate to strong, respectively, with statistically significant (p < 0.001) r values of 0.49 and 0.48 preoperatively and 0.73 and 0.65 postoperatively. Correlation of the symptom section of the GNKSS and bodily pain domain of the SF-36 was also strong pre- and postoperatively. Regarding responsiveness, all domains of the GNKSS showed large changes except the expectation domain. The symptom and functional sections of the GNKSS showed higher responsiveness than the corresponding pain and function domains of the WOMAC and bodily pain and physical function domains of the SF-36. Also, the total score changes were larger for the GNKSS compared with the WOMAC. No floor or ceiling effect was observed. Reliability was excellent with ICCs of 0.83 to 0.97 as an indicator of test-retest reliability and Cronbach's α values of 0.78 to 0.85 preoperatively and 0.92 to 0.94 postoperatively as an indicator of internal consistency for all domains and subdomains.Conclusions: The GNKSS is a valid, responsive, reliable, and consistent outcome measurement tool that may be used to evaluate the outcome of TKA.Level Of Evidence: Level II, diagnostic study. [ABSTRACT FROM AUTHOR]

Abstract Introduction Neuroinflammation is associated with several neurological disorders, including Alzheimer's disease (AD). The translocator protein 18 kDa (TSPO), due to its overexpression during microglial activation and relatively low levels in the brain under normal neurophysiological conditions, is commonly used as an in vivo biomarker for neuroinflammation. Reported here is the preclinical evaluation of [18F]F-DPA, a promising new TSPO-specific radioligand, as a tool for the detection of activated microglia at different ages in the APP/PS1-21 mouse model of AD and a blocking study to determine the specificity of the tracer. Methods [18F]F-DPA was synthesised by the previously reported electrophilic 18F-fluorination methodology. In vivo PET and ex vivo brain autoradiography were used to observe the tracer distribution in the brains of APP/PS1-21 and wildtype mice at different ages (4.5–24 months). The biodistribution and degree of metabolism of [18F]F-DPA were analysed and the specificity of [18F]F-DPA for its target was determined by pre-treatment with PK11195. Results The in vivo PET imaging and ex vivo brain autoradiography data showed that [18F]F-DPA uptake in the brains of the transgenic animals increased with age, however, there was a drop in the tracer uptake at 19 mo. Despite the slight increase in [18F]F-DPA uptake with age in healthy animal brains, significant differences between wildtype and transgenic animals were seen in vivo at 9 months and ex vivo already at 4.5 months. The specificity study demonstrated that PK11195 can be used to significantly block [18F]F-DPA uptake in all the brain regions studied. Conclusions In vivo time activity curves plateaued at approximately 20–40 min suggesting that this is the optimal imaging time. Significant differences in vivo are seen at 9 and 12 mo. Due to the higher resolution, ex vivo autoradiography with [18F]F-DPA can be used to visualise activated microglia at an early stage of AD pathology. [ABSTRACT FROM AUTHOR]

Background: Low back pain (LBP) is a major healthcare problem causing tremendous economic costs. Methods: Clinical manifestation of LBP was characterized in 35,446 patients. We focused on the comparison of the acute, subacute, and chronic LBP stage with regard to patients' ages, based on epidemiologic and clinical questionnaires (eg, painDETECT Questionnaire, Pain Disability Index), pain intensity, pain descriptors, and functional impairment. Results: We found that neuropathic components were most frequent in chronic LBP patients at the ages of 51 to 60 years. Elderly LBP patients showed a decrease in neuropathic and an increase in nociceptive pain. The most frequently reported pain descriptors were "pressure pain" and "pain attacks" through all stages of LBP, whereas "burning" and "prickling" were most frequent in the chronic stage. Patients after back surgery presented neuropathic pain symptoms most frequently and had the highest amount of pain medication intake. Conclusions: Burning and prickling were revealed as possible indicators for LBP chronicity. Combined with pain attacks and pressure pain, these 4 pain descriptors might be a promising adjunct to pain intensity in terms of outcome parameters for future LBP studies. The decrease of neuropathic pain syndromes in the elderly might be explained by degenerative processes. The presented work provides important insights on LBP management in the acute, subacute, and chronic stages. [ABSTRACT FROM AUTHOR]

Objective: This study uses the Support Network Assessment for Practice (SNAP) approach to measure the support provided to young people transitioning from foster care. Methods: The SNAP was administered on two occasions, approximately 7 months apart, to a cohort of transition-age foster youth (n = 27). Analyses investigated measurement reliability and sensitivity to change for network-level characteristics as well as baseline factors associated with relationship stability. Results: Most network-level indicators had strong test–retest correlations, and differences in mean scores over time also were detected, suggesting measurement sensitivity to change. Respondents were able to explain most observed changes in their networks, further suggesting reliable measurement. Stable relationships were those reported as stronger and providing more multifaceted support and those with family members and/or parent figures. Discussion: The SNAP approach could be used to facilitate planning around support needs for youth transitioning out of foster care and to evaluate efforts to enhance support networks. [ABSTRACT FROM AUTHOR]