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This work is concerned with synthetic microstructure models of polycrystalline materials. Once a representation of the microstructure is generated, the individual grains need to be furnished with suitable crystal orientations, matching a specific crystal orientation distribution. We introduce a novel method for this task, which permits to prescribe the orientations based on tensorial Fourier coefficients. This compact representation gives rise to the texture coefficient optimization for prescribing orientations method, enabling the determination of representative orientations for digital polycrystalline microstructures. We compare the proposed method to established and dedicated algorithms in terms of the linear elastic as well as the non-linear plastic behavior of a polycrystalline material.

Multiple trans-synaptic complexes organize synapse development, yet their roles in the mature brain and cooperation remain unclear. We analyzed the postsynaptic adhesion protein LRRTM1 in the prefrontal cortex (PFC), a region relevant to cognition and disorders. LRRTM1 knockout (KO) mice had fewer synapses, and we asked whether other synapse organizers counteract further loss. This determined that the immunoglobulin family member SynCAM 1 controls synapse number in PFC and was upregulated upon LRRTM1 loss. Combined LRRTM1 and SynCAM 1 deletion substantially lowered dendritic spine number in PFC, but not hippocampus, more than the sum of single KO impairments. Their cooperation extended presynaptically, and puncta of Neurexins, LRRTM1 partners, were less abundant in double KO (DKO) PFC. Electrophysiology and fMRI demonstrated aberrant neuronal activity in DKO mice. Further, DKO mice were impaired in social interactions and cognitive tasks. Our results reveal concerted roles of LRRTM1 and SynCAM 1 across synaptic, network, and behavioral domains.

In this work, we advocate using Bayesian techniques for inversely identifying material parameters for multiscale crystal plasticity models. Multiscale approaches for modeling polycrystalline materials may significantly reduce the effort necessary for characterizing such material models experimentally, in particular when a large number of cycles is considered, as typical for fatigue applications. Even when appropriate microstructures and microscopic material models are identified, calibrating the individual parameters of the model to some experimental data is necessary for industrial use, and the task is formidable as even a single simulation run is time consuming (although less expensive than a corresponding experiment). For solving this problem, we investigate Gaussian process based Bayesian optimization, which iteratively builds up and improves a surrogate model of the objective function, at the same time accounting for uncertainties encountered during the optimization process. We describe the approach in detail, calibrating the material parameters of a high-strength steel as an application. We demonstrate that the proposed method improves upon comparable approaches based on an evolutionary algorithm and performing derivative-free methods.

A retrospective chart review was conducted on 85 renal transplant patients aged 19-88 years, treated with denosumab or bisphosphonate therapy. Bone densitometry measures were compared between treatment groups at baseline; at years 1, 2, and 3; and at final follow-up (average of 3.4 years). Both bisphosphonate and denosumab treatments increased lumbar spine bone density; however, the effect of denosumab was greater compared with that of bisphosphonate treatment. Denosumab treatment increased femoral neck BMD, whereas bisphosphonate treatment had a mean decrease in femoral neck BMD at final follow-up. Thus, our study provides evidence for the efficacy of denosumab treatment in renal transplant patients. Caution around hypocalcemia is warranted. We recommend more prospective studies to analyze the effects of long-term antiresorptive therapy in patients with a renal transplant.To compare the clinical effectiveness and safety between the use of denosumab and bisphosphonates on bone density and incidence of adverse events in renal transplant patients.A retrospective chart review was conducted on 85 renal transplant patients aged 19-88 years, treated with denosumab or bisphosphonate therapy. Bone densitometry measures were compared between treatment groups at baseline; years 1, 2, and 3; and at final follow-up (average of 3.4 years).Absolute change in lumbar spine and femoral neck BMD over the treatment period was 0.029 ± 0.075 g/cmBoth treatments increased lumbar spine BMD; however, the effect of denosumab was greater compared with that of bisphosphonate treatment. Our study provides evidence for the efficacy of denosumab treatment in renal transplant patients. Caution around hypocalcemia is warranted. We recommend more prospective studies to analyze the effects of long-term antiresorptive therapy in patients with a renal transplant.

We show the existence of many infinite classes of permutations over finite fields and bent functions by extending the notion of linear translators, introduced by Kyureghyan (J. Combin. Theory Ser. A 118(3), 1052–1061, 2011). We call these translators Frobenius translators since the derivatives of $f:{\mathbb F}_{p^{n}} \rightarrow {\mathbb F}_{p^{k}}$, where n = rk, are of the form $f(x+u\gamma )-f(x)=u^{p^{i}}b$, for a fixed $b \in {\mathbb F}_{p^{k}}$ and all $u \in {\mathbb F}_{p^{k}}$, rather than considering the standard case corresponding to i = 0. It turns out that Frobenius translators correspond to standard linear translators of an exponentiated version of f, namely to $f^{p^{k-i}}$ with respect to $b^{p^{k-i}}$. Nevertheless, this concept turns out to be useful for providing further explicit specification of a rather rare family {f} of quadratic polynomials (especially sparse ones) admitting linear translators. In this direction, we solve a few open problems in the recent article (Cepak et al., Finite Fields Appl. 45, 19–42, 2017) concerning the existence and an exact specification of f admitting classical linear translators. In addition, an open problem introduced in Hodžic et al. (2018), of finding a triple of bent functions f1,f2,f3 such that their sum f4 is bent and that the sum of their duals satisfies $f_{1}^{*}+f_{2}^{*}+f_{3}^{*}+f_{4}^{*}=1$, is also resolved. We also specify two huge families of permutations over ${\mathbb F}_{p^{n}}$ related to the condition that $G(y)=-L(y)+(y+\delta )^{s}-(y+\delta )^{p^{k}s}$ permutes the set ${\mathcal S}=\{\beta \in {\mathbb F}_{p^{n}}: T{r_{k}^{n}}(\beta )=0\}$, where n = 2k and p > 2. Finally, we give some generalizations of constructions of bent functions in Mesnager et al. (2017) and describe some new bent families using the permutations found in Cepak et al. (Finite Fields Appl. 45, 19–42, 2017).

3D printing is now widely used in aerospace, healthcare, energy, automotive and other industries. Metal printing, in particular, is the fastest growing sector, yet its development presents scientific, technological and economic challenges that must be understood and addressed.

Drainage (or stormwater) systems are a potential source of marine debris. Approximately 67 km (33%) of the land along the Mediterranean coast of Israel is considered urban, covered by concrete and asphalt. The purpose of the present pilot study was to determine the composition of the solid waste in a drainage system and evaluate to what extent municipal sources contribute to marine debris. We sampled the waste in Netanya, a medium-size city (245,000 residents) on the central Mediterranean coast of Israel. Samples were taken from seven street stormwater receptacles prior to the first significant rain and then on the beach near a drainage outlet, a few hours after this substantial rain. In terms of composition of the debris, paper, cigarette butts, and sanitary items made up a higher proportion of the drainage system debris than those items did on the beach. In contrast, single-use items, polystyrene pieces, bottle caps, and plastic drinking bottles composed more of the debris on the beaches compared to the debris in the drainage system. Overall, we found that municipal stormwater systems contribute significant amounts of solid waste to marine debris on Israeli beaches. Preventing the waste from reaching the streets might help reduce marine debris on the beaches, especially at the beginning of the rainy season. There are multiple solutions, but all will require creativity and resources and constant maintenance. Educating the public to prevent disposal of solid waste items in the street is also important as a way to reduce terrestrial as well as marine debris.

Improving the medical care of deceased organ donors to increase transplant rates and improve allograft function requires an understanding of the current epidemiology and clinical practices of deceased donation within intensive care units (ICUs). Herein, we report the results of our investigation into the feasibility of a multicentre prospective cohort study addressing the afformentioned issues. We conducted a 12-month prospective observational cohort study in six ICUs and one coronary care unit in Hamilton, Canada. We included consecutive children and adults following consent for deceased organ donation (including neurologic determination of death [NDD] or donation after circulatory death [DCD]). Intensive care unit research staff recorded donor management data from hospital records, extending from one day prior to the consent for organ donation up to the time of organ retrieval. The provincial Organ Donation Organization (ODO) supplemented these data and, additionally, provided data on corresponding organ recipients. We identified, evaluated, and measured three potential obstacles to the feasibility of a national cohort study: obtaining authorization to implement the study with a waiver of research consent, accessibility of transplant recipient data, and the time required to complete very detailed case report forms (CRFs), with valuable lessons learned for implementation in future projects. The local Research Ethics Board and the ODO Privacy Office both authorized the recording of donor and recipient study data with a waiver of research consent. Sixty-seven consecutive consented donors were included (31 NDD and 36 DCD donors); 50 of them provided 144 organs for transplantation to 141 recipients. We identified the age and sex of the recipients as well as the location and date of transplant for all organ recipients in Ontario; however, we obtained no recipient data for six organs transported outside of Ontario. Intensive care unit research staff estimated that future CRF completion will require five to seven hours per patient. The Hamilton-DONATE pilot study supports the feasibility of a larger cohort study to describe the epidemiology and clinical practices related to deceased donor care in Canada. wwwclinicaltrials.gov (NCT02902783). Registered 16 September 2016.

Temperate grasslands and their dependent species are exposed to high variability in weather and climate due to the lack of natural buffers such as forests. Grassland birds are particularly vulnerable to this variability, yet have failed to shift poleward in response to recent climate change like other bird species in North America. However, there have been few studies examining the effect of weather on grassland bird demography and consequent influence of climate change on population persistence and distributional shifts. The goal of this study was to estimate the vulnerability of Henslow’s Sparrow (Ammodramus henslowii), an obligate grassland bird that has been declining throughout much of its range, to past and future climatic variability. We conducted a demographic meta-analysis from published studies and quantified the relationship between nest success rates and variability in breeding season climate. We projected the climate-demography relationships spatially, throughout the breeding range, and temporally, from 1981 to 2050. These projections were used to evaluate population dynamics by implementing a spatially explicit population model. We uncovered a climate-demography linkage for Henslow’s Sparrow with summer precipitation, and to a lesser degree, temperature positively affecting nest success. We found that future climatic conditions—primarily changes in precipitation—will likely contribute to reduced population persistence and a southwestward range contraction. Future distributional shifts in response to climate change may not always be poleward and assessing projected changes in precipitation is critical for grassland bird conservation and climate change adaptation.

Beyond the recognized importance of protecting large areas of contiguous habitat, conservation efforts for many species are complicated by the fact that patch suitability may also be affected by characteristics of the landscape within which the patch is located. Currently, little is known about the spatial scales at which species respond to different aspects of the landscape surrounding an occupied patch. Using grassland bird point count data, we describe an approach to evaluating scale-specific effects of landscape composition on patch occupancy. We used data from 793 point count surveys conducted in idle and grazed grasslands across Wisconsin, USA from 2012 to 2014 to evaluate scale-dependencies in the response of grassland birds to landscape composition. Patch occupancy models were used to evaluate the relationship between occupancy and landscape composition at scales from 100 to 3000 m. Bobolink (Dolichonyx oryzivorus) exhibited a pattern indicating selection for grassland habitats in the surrounding landscape at all spatial scales while selecting against other habitats. Eastern Meadowlark (Sturnella magna) displayed evidence of scale sensitivity for all habitat types. Grasshopper Sparrow (Ammodramus savannarum) showed a strong positive response to pasture and idle grass at all scales and negatively to cropland at large scales. Unlike other species, patch occupancy by Henslow’s Sparrow (A. henslowii) was primarily influenced by patch area. Our results suggest that both working grasslands (pasture) and idle conservation grasslands can play an important role in grassland bird conservation but also highlight the importance of considering species-specific patch and landscape characteristics for effective conservation.

Fluid resuscitation, along with the early administration of antibiotics, is the cornerstone of treatment for patients with sepsis. However, whether differences in resuscitation fluids impact on the requirements for renal replacement therapy (RRT) remains unclear. To examine this issue, we performed a network meta-analysis (NMA), including direct and indirect comparisons, that addressed the effect of different resuscitation fluids on the use of RRT in patients with sepsis. The data sources MEDLINE, EMBASE, ACPJC, CINAHL and Cochrane Central Register were searched up to March 2014. Eligible studies included randomized trials reported in any language that enrolled adult patients with sepsis or septic shock and addressed the use of RRT associated with alternative resuscitation fluids. The risk of bias for individual studies and the overall certainty of the evidence were assessed. Ten studies (6664 patients) that included a total of nine direct comparisons were assessed. NMA at the four-node level showed that an increased risk of receiving RRT was associated with fluid resuscitation with starch versus crystalloid [odds ratio (OR) 1.39, 95% credibility interval (CrI) 1.17-1.66, high certainty]. The data suggested no difference between fluid resuscitation with albumin and crystalloid (OR 1.04, 95% CrI 0.78-1.38, moderate certainty) or starch (OR 0.74, 95% CrI 0.53-1.04, low certainty). NMA at the six-node level showed a decreased risk of receiving RRT with balanced crystalloid compared to heavy starch (OR 0.50, 95% CrI 0.34-0.74, moderate certainty) or light starch (OR 0.70, 95% CrI 0.49-0.99, high certainty). There was no significant difference between balanced crystalloid and saline (OR 0.85, 95% CrI 0.56-1.30, low certainty) or albumin (OR 0.82, 95% CrI 0.49-1.37, low certainty). Of note, these trials vary in terms of case mix, fluids evaluated, duration of fluid exposure and risk of bias. Imprecise estimates contributed to low confidence in most estimates of effect. Among the patients with sepsis, fluid resuscitation with crystalloids compared to starch resulted in reduced use of RRT; the same may be true for albumin versus starch.

Kirtland’s warblers (Dendroica kirtlandii) persist in a naturally patchy environment of young, regenerating jack pine forests (i.e., 5–23 years old) created after wildfires and human logging activities. We examined how changing landscape structure from 26 years of forest management and wildfire disturbances influenced population size and spatial dispersion of male Kirtland’s warblers within their restricted breeding range in northern Lower Michigan, USA. The male Kirtland’s warbler population was six times larger in 2004 (1,322) compared to 1979 (205); the change was nonlinear with 1987 and 1994 identified as significant points of change. In 1987, the population trend began increasing after a slowly declining trend prior to 1987, and the rate of increase appeared to slow after 1994. Total amount of suitable habitat and the relative area of wildfire-regenerated habitat were the most important factors explaining population trend. Suitable habitat increased 149% primarily due to increasing plantations from forest management. The relative amount and location of wildfire-regenerated habitat modified the distribution of males among various habitat types, and the spatial variation in their abundance across the primary breeding range. These findings indicate that the Kirtland’s warbler male population shifted its use of habitat types temporally and spatially as the population increased and as the relative availability of habitats changed through time. We demonstrate that researchers and managers need to consider not only habitat quality, but the temporal and the spatial context of habitat availability and population levels when making habitat restoration decisions.

Serotonin is implicated in stress-related psychopathologies. Two isoforms of the rate-limiting enzyme of serotonin biosynthesis, tryptophan hydroxylase, TPH1 and TPH2, are known. We show here that in the rat dorsal raphe nucleus (DRN), the nucleus that contains the highest number of 5-HT neurons in the brain, TPH1 mRNA reveals a low level of expression but is detectable both by quantitative real-time PCR and in situ hybridization whereas in the pineal gland (PiG), TPH1 mRNA is strongly expressed. To examine effects of stress on TPH expression we exposed male Wistar rats to daily restraint stress for 1 week. As shown by quantitative real-time PCR, TPH1 mRNA is 2.5-fold upregulated by the stress in DRN but not in PiG. Using 3'-RACE, we identified two TPH2 mRNA splice variants in the rat DRN which differ in the length of their 3'-untranslated regions (UTRs). TPH2b (with a short 3'-UTR) is the predominant variant in the DRN, whereas TPH2a (with a longer 3'-UTR) shows a low abundance in this nucleus. In the PiG, only TPH2b is detectable revealing a low level of expression. Expression of both TPH2 splice variants is not affected by stress, neither in DRN nor in the PiG. These data indicate that TPH1 in the serotonergic neurons of the DRN might be relevant for stress-induced psychopathologies.

Fragmentation of grasslands has been implicated in grassland bird population declines. Multi-scale models are being increasingly used to assess potential factors that influence grassland bird presence, abundance, and productivity. However, studies rarely assess fragmentation metrics, and seldom evaluate more than two scales or interactions among scales. We evaluated the relative importance of characteristics at multiple scales to patterns in relative abundance of Savannah Sparrow (Passerculus sandwichensis), Grasshopper Sparrow (Ammodramus savannarum), Eastern Meadowlark (Sturnella magna), and Bobolink (Dolichonyx oryzivorus). We surveyed birds in 74 southwestern Wisconsin pastures from 1997 to 1999 and compared models with explanatory variables from multiple scales: within-patch vegetation structure (microhabitat), patch (macrohabitat), and three landscape extents. We also examined interactions between macrohabitat and landscape factors. Core area of pastures was an important predictor of relative abundance, and composition of the landscape was more important than configuration. Relative abundance was frequently higher in pastures with more core area and in landscapes with more grassland and less wooded area. The direction and strength of the effect of core pasture size on relative abundance changed depending on amount of wooded area in the landscape. Relative abundance of grassland birds was associated with landscape variables more frequently at the 1200-m scale than at smaller scales. To develop better predictive models, parameters at multiple scales and their interactive effects should be included, and results should be evaluated in the context of microhabitat variability, landscape composition, and fragmentation in the study area.

Retinitis pigmentosa is a leading cause of inherited blindness, with no effective treatment currently available. Mutations primarily in genes expressed in rod photoreceptors lead to early rod death, followed by a slower phase of cone photoreceptor death. Rd1 mice provide an invaluable animal model to evaluate therapies for the disease. We previously reported that overexpression of histone deacetylase 4 (HDAC4) prolongs rod survival in rd1 mice. Here we report a key role of a short N-terminal domain of HDAC4 in photoreceptor protection. Expression of this domain suppresses multiple cell death pathways in photoreceptor degeneration, and preserves even more rd1 rods than the full-length HDAC4 protein. Expression of a short N-terminal domain of HDAC4 as a transgene in mice carrying the rd1 mutation also prolongs the survival of cone photoreceptors, and partially restores visual function. Our results may facilitate the design of a small protein therapy for some forms of retinitis pigmentosa.

Since 1956, Southern Giant Petrels on the Frazier Islands, East Antarctica, have been counted with different census techniques, sometimes varying within seasons and among islands, which hindered analysis of the data. Protective measures for the islands from 1986 onwards have increased the need for reliable long-term census data, but reduced the ways to collect these data. Published and unpublished data were re-examined, and population trends were reconstructed based on two relatively standardised techniques: the number of active chicks (AC) and the number of apparently occupied nests (AON) around hatching. AC-values from Nelly Island from 1959 to 1998 indicate substantial periodic fluctuations, but no consistent long-term change. Since the late 1970s, AC-values on the other two islands and AON-values suggest that the breeding population may have grown by 35%. This recent growth, however, is within the extent of periodic fluctuations observed in Southern Giant Petrel population that is stable over the long term.

/ An index of upland wildlife habitat was developed to investigate patterns and changes in habitat over time, using four years (1920, 1940, 1964, 1987) and the state of Illinois as an example. The index was composed of two subdivisions that described, at the county level, the quantity of wildlife habitat and a third subdivision that described farming disturbances that impacted the quality of the habitat. Data came from the US Census of Agriculture. The first subdivision that reflected quantity of habitat was called the wildlife habitat subdivision and was the sum of percentage woodland on farms, percentage farmland in nonrow crops, and percentage farmland in set-aside programs. The second subdivision that reflected the quantity of habitat was termed the soil-related features subdivision and was the sum of the percentage of farmland that was not highly erodible, the percentage of farmland in soil-protecting crops, and the percentage of farmland in conservation tillage. The third subdivision, reflecting the quality of the habitat, was the farming disturbance subdivision and was the sum of the percentage of grazing and the percentage of land on which fertilizers, pesticides, and herbicides were applied. Overall, major decreases occurred between 1920 and 1987 in the subdivisions reflecting the quantity of wildlife habitat and a major increase occurred in the subdivision associated with farming disturbance, reflecting the intensification of agriculture in the state. However, there was variability throughout the state, with some counties being more favorable to wildlife (as measured by the subdivisions) than others. Most of the changes within the state for the subdivisions reflecting quantity of upland wildlife habitat occurred during 1940 while changes in the farming disturbance subdivision (reflecting habitat quality) occurred in 1964. By 1987, the western and southern parts of Illinois were the most favorable for wildlife as reflected in all three subdivisions. Upland wildlife harvest indices were related to the subdivisions in 1964 and 1987, when harvest indices were available. Cottontail and northern bobwhite harvests were higher in counties with higher amounts of the wildlife habitat subdivision in both years. Cottontail harvest was also higher in counties with lower levels of the farming disturbance subdivision in 1964 and higher levels of soil-related features subdivision in 1987. Indices at the county level have the potential to be used in a multiscale analysis to investigate the impact of policy changes on large-scale areas of the Midwest and to develop regional perspectives of the impacts of agriculture on upland wildlife and their habitats.KEY WORDS: Upland wildlife; Habitat; Agriculture; Illinois

Background Several recent studies have highlighted the important role of immunity-related molecules in synaptic plasticity processes in the developing and adult mammalian brains. It has been suggested that neuronal MHCI (major histocompatibility complex class I) genes play a role in the refinement and pruning of synapses in the developing visual system. As a fast evolutionary rate may generate distinct properties of molecules in different mammalian species, we studied the expression of MHCI molecules in a nonhuman primate, the common marmoset monkey (Callithrix jacchus). Methods and results Analysis of expression levels of MHCI molecules in the developing visual cortex of the common marmoset monkeys revealed a distinct spatio-temporal pattern. High levels of expression were detected very early in postnatal development, at a stage when synaptogenesis takes place and ocular dominance columns are formed. To determine whether the expression of MHCI molecules is regulated by retinal activity, animals were subjected to monocular enucleation. Levels of MHCI heavy chain subunit transcripts in the visual cortex were found to be elevated in response to monocular enucleation. Furthermore, MHCI heavy chain immunoreactivity revealed a banded pattern in layer IV of the visual cortex in enucleated animals, which was not observed in control animals. This pattern of immunoreactivity indicated that higher expression levels were associated with retinal activity coming from the intact eye. Conclusions These data demonstrate that, in the nonhuman primate brain, expression of MHCI molecules is regulated by neuronal activity. Moreover, this study extends previous findings by suggesting a role for neuronal MHCI molecules during synaptogenesis in the visual cortex.