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Implementation of wildfire‐ and climate‐adaptation strategies in seasonally dry forests of western North America is impeded by numerous constraints and uncertainties. After more than a century of resource and land use change, some question the need for proactive management, particularly given novel social, ecological, and climatic conditions. To address this question, we first provide a framework for assessing changes in landscape conditions and fire regimes. Using this framework, we then evaluate evidence of change in contemporary conditions relative to those maintained by active fire regimes, i.e., those uninterrupted by a century or more of human‐induced fire exclusion. The cumulative results of more than a century of research document a persistent and substantial fire deficit and widespread alterations to ecological structures and functions. These changes are not necessarily apparent at all spatial scales or in all dimensions of fire regimes and forest and nonforest conditions. Nonetheless, loss of the once abundant influence of low‐ and moderate‐severity fires suggests that even the least fire‐prone ecosystems may be affected by alteration of the surrounding landscape and, consequently, ecosystem functions. Vegetation spatial patterns in fire‐excluded forested landscapes no longer reflect the heterogeneity maintained by interacting fires of active fire regimes. Live and dead vegetation (surface and canopy fuels) is generally more abundant and continuous than before European colonization. As a result, current conditions are more vulnerable to the direct and indirect effects of seasonal and episodic increases in drought and fire, especially under a rapidly warming climate. Long‐term fire exclusion and contemporaneous social‐ecological influences continue to extensively modify seasonally dry forested landscapes. Management that realigns or adapts fire‐excluded conditions to seasonal and episodic increases in drought and fire can moderate ecosystem transitions as forests and human communities adapt to changing climatic and disturbance regimes. As adaptation strategies are developed, evaluated, and implemented, objective scientific evaluation of ongoing research and monitoring can aid differentiation of warranted and unwarranted uncertainties. [ABSTRACT FROM AUTHOR]

Context: Montane grasslands and forest-grassland ecotones are unique and dynamic components of many landscapes, but the processes that regulate their dynamics are difficult to observe over ecologically relevant time spans. Objectives: We aimed to demonstrate the efficacy of using grassland-forest ecotone trees to reconstruct spatial and temporal properties of the historical fire regime in a complex landscape of montane forests and adjacent grasslands. Methods: We sampled and crossdated fire-scarred trees along ecotones and compared variations in historical fire occurrence within and among nine adjoining valle basins in a 10,158 ha landscape. We analyzed fire year extensiveness, climate regulation, and the occurrence of consecutive fire years. Results: The resulting tree-ring record covers 1240–2005 AD, with 296 trees recording 125 replicated fire years during the analysis period 1601–1902 AD. Mean fire intervals for all events recorded on two or more trees ranged from 4.7 to 13.6 years in individual valles, and a mean of 2.4 ± 1.7 (SD) years at the landscape scale. Between 1660 and 1902, extensive fires occurring in six or more valles occurred 15 times, on average at ~ 17-year intervals; 29 moderately widespread fires (3–5 valles) occurred during this period, at 8.7 year intervals on average. Widespread events occurred in years with a significantly lower Palmer Drought Severity Index (PDSI) preceded by years of significantly positive PDSI, indicating conditions favorable for fine fuel production. Spatial reconstruction of fire extent revealed multiple occurrences of consecutive-year fires burning non-overlapping areas, associated with persistent low PDSI anomalies preceded by positive conditions in antecedent years. Conclusions: A landscape spatiotemporal approach to reconstructing fire regimes of montane forest-grassland complexes provides a valuable baseline for guiding prescribed and natural fire management at large spatial scales. [ABSTRACT FROM AUTHOR]

Forests of the western United States are undergoing substantial stress from fire exclusion and increasing effects of climate change, altering ecosystem functions and processes. Changes in broad‐scale drivers of forest community composition become apparent in their effect on survivorship and regeneration, driving demographic shifts. Here we take a community functional approach to forest demography, by investigating mean drought or shade functional tolerance in community assemblages. We created the Community Mean Tolerance Index (CMTI), a response metric utilizing drought/shade tolerance trade‐offs to identify communities undergoing demographic change from a functional trait perspective. We applied the CMTI to Forest Inventory and Analysis data to investigate demographic trends in drought and shade tolerance across the southern Rocky Mountains. To find the major drivers of change in community tolerance within and across forest types, we compared index trends to climate and fire‐exclusion‐driven disturbance, and identified areas where demographic change was most pronounced. We predicted that greater shifts in drought tolerance would occur at lower forest type ecotones where climate stress is limiting and that shifts in shade tolerance would correspond to excursions from the historic fire regime leading to greater changes in forest types adapted to frequent, low‐intensity fire. The CMTI was applied spatially to identify sites likely to transition to oak shrubfield, where disturbance history combined with a species‐driven demographic shift toward drought tolerance. Within forest types, lower elevations are trending toward increased drought tolerance, while higher elevations are trending toward increased shade tolerance. Across forest types, CMTI difference peaked in mid‐elevation ponderosa pine and mixed‐conifer forests, where fire exclusion and autecology drive demographic changes. Peak CMTI difference was associated with fire exclusion in forest types adapted to frequent fire. At higher elevations, site‐level stand dynamics appear to be influencing demographic tolerance trends more than broad climate drivers. Through a community demographic approach to functional traits, the CMTI highlights areas and forest types where ecosystem function is in the process of changing, before persistent vegetation type change occurs. Applied to regional plot networks, the CMTI provides an early warning of shifts in community functional processes as climate change pressures continue. [ABSTRACT FROM AUTHOR]

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The article presents a study which evaluates whether the sowing of spring cereals, including hard red spring wheat, spring barley, and oat, in early spring would result in a yield increase. The field trials conducted from 2003 to 2004 at five different locations in southern Ontario using commercial no-till planting equipment are discussed. Topics include the effects of frost seeding on wheat, oat, and barley, plant density, and early harvest.

The aim of this meta-analysis was to summarize the short- and long-term effects of bilateral deep brain stimulation of the subthalamic nucleus ( STN- DBS) on gait and freezing of gait ( FOG) in Parkinson's disease and to detect predictors of post-stimulation outcome. A comprehensive review of the literature was conducted up to October 2015 using Medline Ovid databases for studies analyzing the effect of bilateral STN- DBS on FOG and/or gait. Sixteen studies with available data for the gait item (no. 29) of the Unified Parkinson's Disease Rating Scale ( UPDRS) and six studies with the FOG item (no. 14) were included. Data were summarized for the following follow-up periods: 6-15, 24-48 and >48 months. For the medication (Med)-Off/stimulation(Stim)-On condition compared with baseline Med-Off, STN- DBS significantly improved gait on average from 2.43 to 0.96, 2.53 to 1.31 and 2.56 to 1.40 points at 6-15, 24-48 and >48 months, respectively ( P < 0.05). Pre-operative levodopa responsiveness of UPDRS- III and Med-Off severity of gait were the predictors of this beneficial effect. STN-DBS significantly improved FOG for the Med-Off/Stim-On condition compared with baseline on average from 2.26 to 0.82, 2.43 to 1.13 and 2.48 to 1.38 points at 6-15, 24-48 and >48 months, respectively ( P < 0.05). There was no significant effect in the Med-On/Stim-On condition. This meta-analysis showed a robust improvement of gait and FOG by STN- DBS for more than 4 years in the Med-Off/Stim-On condition. No beneficial effect was found for the On state of medication. Pre-operative levodopa responsiveness of global motor performance ( UPDRS- III) is the strongest predictor of the effect of deep brain stimulation on gait. [ABSTRACT FROM AUTHOR]

Pompe disease, caused by deficiency of acid alpha-glucosidase (GAA), leads to widespread glycogen accumulation and profound neuromuscular impairments. There has been controversy, however, regarding the role of central nervous system pathology in Pompe motor dysfunction. We hypothesized that absence of GAA protein causes progressive activation of neuropathological signaling, including pathways associated with cell death. To test this hypothesis, genomic data (Affymetrix Mouse Gene Array 2.0ST) from the midcervical spinal cord in 6 and 16 mo old Pompe (Gaa−/−) mice were evaluated (Broad Institute Molecular Signature Database), along with spinal cord histology. The midcervical cord was selected because it contains phrenic motoneurons, and phrenic-diaphragm dysfunction is prominent in Pompe disease. Several clinically important themes for the neurologic etiology of Pompe disease emerged from this unbiased genomic assessment. First, pathways associated with cell death were strongly upregulated as Gaa−/− mice aged, and motoneuron apoptosis was histologically verified. Second, proinflammatory signaling was dramatically upregulated in the Gaa−/− spinal cord. Third, many signal transduction pathways in the Gaa−/− cervical cord were altered in a manner suggestive of impaired synaptic function. Notably, glutamatergic signaling pathways were downregulated, as were “synaptic plasticity pathways” including genes related to neuroplasticity. Fourth, many genes and pathways related to cellular metabolism are dysregulated. Collectively, the data unequivocally confirm that systemic absence of GAA induces a complex neuropathological cascade in the spinal cord. Most importantly, the results indicate that Pompe is a neurodegenerative condition, and this underscores the need for early therapeutic intervention capable of targeting the central nervous system. [ABSTRACT FROM AUTHOR]

Jatropha curcas (L.) has gained popularity as a biodiesel plant to serve as an alternative fuel source and generate income to small landholders. The success of J. curcas as alternative fuel source and income generation depends on the identification of genetically divergent materials of the plant and developing superior planting stocks for farmers. This paper presents genetic diversity assessment of 40 representative accessions drawn from 90 accessions collected from ten regions of Ghana based on their seed yield performance. Random Amplified Polymorphic DNA (RAPD) analysis on the 40 accessions with ten primers revealed an average polymorphism of 24.99%. Genotype Genotype*Environmental biplot analysis which incorporates divergence effects due to genotype (PC1) and interactions between genotype and field parameters (PC2) was 44.7%. Hence the RAPD information indicates narrow genetic diversity among the accessions used in the study and J. curcas germplasm in Ghana. It is therefore recommended that local germplasm of J. curcas should be officially conserved and immediate efforts be made to widen the genetic base through research and introduction from other regions. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) of the internal globus pallidus (Gpi) is an effective therapy for various types of dystonia. The authors describe their technical approach for securing appropriate placement of the stimulating electrodes within the Gpi under general anaesthesia, including MRI based individualised anatomical targeting combined with electrophysiological mapping of the Gpi using micro-recording (MER) as well as macrostimulation and report the subsequent clinical outcome and complications using this method. We studied 42 patients (male-female ratio 25:17; mean age 43.6 years, range 9 to 74 years) consecutively operated at the Department of Neurosurgery, University Hospital Schleswig-Holstein, Campus Kiel, between 2001 – 2006. One patient underwent unilateral implantation after a right-sided pallidotomy 30 years before and strictly unilateral symptoms; all other implantations were bilateral. Two patients had repeat surgery after temporary removal of uni– or bilateral implants secondary to infection. Overall, 86 DBS electrodes were implanted. In 97% of the implantations, at least three microelectrodes were inserted simultaneously for MER and test stimulation. Initial anatomical targeting was based on stereotactic atlas coordinates and individual adaptation by direct visualisation of the Gpi on the stereotactic T2 or inversion-recovery MR images. The permanent electrode was placed according to the results of MER and test stimulations for adverse effects. The average improvement from baseline in clinical ratings using either the Burke-Fahn-Marsden-Dystonia (BFMDRS) or Toronto-Western-Spasmodic-Torticollis (TWSTR) rating scale at the last post-operative follow-up (mean 16.4 ; range 3–48 months) was 64.72% (range 20.39 to 98.52%). The post-operative MRI showed asymptomatic infarctions of the corpus caudatus in three patients and asymptomatic small haemorrhages in the lateral basal ganglia in two patients. One patient died due to a recurrent haemorrhage which occurred three months after the operation. The electrodes were implanted as follows: central trajectory in 64%, medial trajectory in 20%, anterior in 9% and lateral dorsal trajectories in 3.5% each. The reduction in BFMDRS or TWSTR motor score did not differ between the group implanted in the anatomically defined (central) trajectory bilateral (−64.15%, SD 23.8) and the physiologically adopted target (uni– or bilateral) (−63.39%, SD 23.1) indicating that in both groups equally effective positions were chosen within Gpi for chronic stimulation (t-test, p > 0.4). The described technique using stereotactic MRI for planning of the trajectory and direct visualisation of the target, intra-operative MER for delineating the boundaries of the target and macrostimulation for probing the distance to the internal capsule by identifying the threshold for stimulation induced tetanic contractions is effective in DBS electrode implantation in patients with dystonia operated under general anaesthesia. The central trajectory was chosen in only 64%, despite individual adaptation of the target due to direct visualisation of the Gpi in inversion recovery MRI in 43% of the patients, demonstrating the necessity of combining anatomical with neurophysiological information. [ABSTRACT FROM AUTHOR]

Susceptibility to black spot [caused by Mycosphaerella pinodes (Berk. and Blox.) Vestergr.] and weak stem strength in field pea (Pisum sativum L.) are major restrictions to yield, seed quality, and ease of harvest. Previous studies have established that additive genetic variance is present for both traits, and that stem strength is strongly associated with a field test of compressed stem thickness at the base of the stem. This study aimed to improve these two complex traits simultaneously by recurrent selection. Heritabilities and responses to selection for resistance to black spot and stem strength were evaluated during two cycles of recurrent selection after intercrossing diverse genotypes. Response to selection was indicated by a reduction of 10% in the mean black spot leaf disease in the F2 of cycle 2 compared with the F2 of cycle 1, when considered as a percentage of the mean of cycle 1 parents in the same trials. Likewise, there was a 15% increase in stem strength, based on the mean compressed stem thickness in the F2 of cycle 2 compared with the F2 of cycle 1. Broad sense heritability for resistance to black spot leaf disease was moderate (H = 0.63 ± 0.35 across cycles 1 and 2) and for compressed stem thickness was also moderate (H = 0.66 ± 0.34). Genetic gains were realized for both traits simultaneously in the first two cycles and were predicted to be rapid over the next five to six cycles based on a random mating quantitative genetics model. [ABSTRACT FROM AUTHOR]

The 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) sought to determine the prevalence of alcohol use and alcohol use disorders (AUDs), other drug use and drug use disorders (DUDs), and co-use and co-morbidity in the general adult U.S. population. Findings indicate that 5.6 percent of U.S. adults used both alcohol and drugs in the past year and that 1.1 percent had a co-morbid AUD and DUD. Alcohol use prevalence peaked between the ages of 25 and 44 and declined thereafter. The prevalence of other drug use, co-use, AUDs, DUDs, and co-morbid disorders was highest between the ages of 18 and 24 and declined steadily thereafter. Women and men showed similar trends for alcohol use, drug use, and co-use. Among ethnic/racial groups evaluated, Whites displayed the highest rates of alcohol use and American Indians/Alaskan Natives the highest rates of drug use. For AUDs, DUDs, and co-morbid disorders, rates were highest among American Indians/Alaskan Natives. The prevalence of drug use, weekly drug use, and DUDs increased with increasing levels of alcohol consumption and the presence of AUDs. The proportion of people with AUDs who had a co-morbid DUD varied considerably by drug type. These findings have important implications for the development of prevention and intervention approaches. [ABSTRACT FROM AUTHOR]

Prevention of oxidative stress via antioxidants attenuates diaphragm myofiber atrophy associated with mechanical ventilation (MV). However, the specific redox-sensitive mechanisms responsible for this remain unknown. We tested the hypothesis that regulation of skeletal muscle proteolytic activity is a critical site of redox action during MV. Sprague-Dawley rats were assigned to five experimental groups: 1) control, 2) 6 h of MV, 3) 6 h of MV with infusion of the antioxidant Trolox, 4) 18 h of MV, and 5) 18 h of MV with Trolox. Trolox did not attenuate MV-induced increases in diaphragmatic levels of ubiquitin-protein conjugation, polyubiquitin mRNA, and gene expression of proteasomal subunits (20S proteasome a-subunit 7, 14-kDa E2, and proteasome-activating complex PA28). However, Trolox reduced both chymotrypsin-like and peptidylglutamyl peptide hydrolyzing (PGPH)-like 20S proteasome activities in the diaphragm after 18 h of MV. In addition, Trolox rescued diaphragm myofilament protein concentration (μg/mg muscle) and the percentage of easily releasable myofilament protein independent of alterations in ribosomal capacity for protein synthesis. In summary, these data are consistent with the notion that the protective effect of antioxidants on the diaphragm during MV is due, at least in part, to decreasing myofilament protein substrate availability to the proteasome. [ABSTRACT FROM AUTHOR]

Oxidative stress promotes controlled mechanical ventilation (MV)-induced diaphragmatic atrophy. Nonetheless, the signalling pathways responsible for oxidative stress-induced muscle atrophy remain unknown. We tested the hypothesis that oxidative stress down-regulates insulin-like growth factor-1–phosphotidylinositol 3-kinase–protein kinase B serine threonine kinase (IGF-1–PI3K–Akt) signalling and activates the forkhead box O (FoxO) class of transcription factors in diaphragm fibres during MV-induced diaphragm inactivity. Sprague–Dawley rats were randomly assigned to one of five experimental groups: (1) control (Con), (2) 6 h of MV, (3) 6 h of MV with infusion of the antioxidant Trolox, (4) 18 h of MV, (5) 18 h of MV with Trolox. Following 6 h and 18 h of MV, diaphragmatic Akt activation decreased in parallel with increased nuclear localization and transcriptional activation of FoxO1 and decreased nuclear localization of FoxO3 and FoxO4, culminating in increased expression of the muscle-specific ubiquitin ligases, muscle atrophy factor ( MAFbx) and muscle ring finger-1 ( MuRF-1). Interestingly, following 18 h of MV, antioxidant administration was associated with attenuation of MV-induced atrophy in type I, type IIa and type IIb/IIx myofibres. Collectively, these data reveal that the antioxidant Trolox attenuates MV-induced diaphragmatic atrophy independent of alterations in Akt regulation of FoxO transcription factors and expression of MAFbx or MuRF-1. Further, these results also indicate that differential regulation of diaphragmatic IGF-1–PI3K–Akt signalling exists during the early and late stages of MV. [ABSTRACT FROM AUTHOR]

Oxidative stress is an important mediator of diaphragm muscle atrophy and contractile dysfunction during prolonged periods of controlled mechanical ventilation (MV). To date, specific details related to the impact of MV on diaphragmatic redox status remain unknown. To fill this void, we tested the hypothesis that MV-induced diaphragmatic oxidative stress is the consequence of both an elevation in intracellular oxidant production in conjunction with a decrease in the antioxidant buffering capacity. Adult rats were assigned to one of two experimental groups: 1) control or 2) 12 h of MV. Compared with controls, diaphragms from MV animals demonstrated increased oxidant production, diminished total antioxidant capacity, and decreased glutathione levels. Heme oxygenase-1 (HO-1) mRNA and protein levels increased (23.0- and 5.1-fold, respectively) following MV. Thioredoxin reductase-1 and manganese superoxide dismutase mRNA levels were also increased in the diaphragm following MV (2.4- and 1.6-fold, respectively), although no change was detected in the levels of either protein. Furthermore, copper-zinc superoxide dismutase and glutathione peroxidase mRNA were not altered following MV, although protein content decreased -1.3- and -1.7-fold, respectively. We conclude that MV promotes increased oxidant production and impairment of key antioxidant defenses in the diaphragm; collectively, these changes contribute to the MV-induced oxidative stress in this key inspiratory muscle. [ABSTRACT FROM AUTHOR]

Relationships between residual feed intake (RFI) and other performance variables were determined using 54 purebred Angus steers. Individual feed intake and BW gain were recorded during a 70-d post-weaning period to calculate RFI. After the 70-d post-weaning test, steers were fed a finishing ration to a similar fat thickness (FT), transported to a commercial facility, and slaughtered. A subsample of carcasses (n = 32) was selected to examine the relationships among RFI, meat quality, and palatability. Steers were categorized into high (>0.5 SD above the mean; n = 16), medium (mid; ±0.5 SD from the mean; n = 21), and low (<0.5 SD below the mean; n = 17) RFI groups. No differences were detected in ADG, initial BW, and d 71 BW among the high, mid, and low RFI steers. Steers from the high RFI group had a greater DMI (P = 0.004) and feed conversion ratio (FCR; DMI:ADG; P = 0.002) compared with the low RFI steers. Residual feed intake was positively correlated with DMI (r = 0.54; P = 0.003) and FCR (r = 0.42; P = 0.002), but not with initial BW, d 71 BW, d 71 ultrasound FT, initial ultrasound LM area, d 71 ultrasound LM area, or ADG. The FCR was positively correlated with initial BW (r = 0.46; P = 0.0005), d 71 BW (r = 0.34; P = 0.01), and DMI (r = 0.40; P = 0.003) and was negatively correlated with AIDG (r = -0.65; P = 0.001). There were no differences among RFI groups for HCW, LM area, FT, KIPH, USDA yield grade, marbling score, or quality grade. Reflectance color b* scores of steaks from high RFI steers were greater (P = 0.02) than those from low RFI steers. There was no difference between high and low RFI groups for LM calpastatin activity. Warner-Bratzler shear force and sensory panel tenderness and flavor scores of steaks were similar across RFI groups. Steaks from high RFI steers had lower (P = 0.04) off-flavor scores than those from low RFI steers. Cook loss percentages were greater (P = 0.005) for steaks from low RFI steers than for those from mid RFI steers. These data support current views that RFI is independent of ADG, but is correlated with DMI and FCR. Importantly, the data also support the hypothesis that there is no relationship between RFI and beef quality in purebred Angus steers. [ABSTRACT FROM AUTHOR]

Crosses of wheat ( Triticum aestivum L.) Group 5 chromosome substitution lines from three different cultivar backgrounds indicate that there may be multiple alleles for reduced crossability with rye ( Secale cereale L.) and H. bulbosum on both 5A and 5B chromosomes. No reduction in seed set was observed from any of the 5D substitution lines. It was found that the Kr locus on chromosome 5B had a more pronounced affect on both rye and H. bulbosum crossability than the Kr locus on chromosome 5A and that the effects of both loci were cumulative. The Kr alleles affected both rye and H. bulbosum crossability in a linear, or additive, fashion. The Kr allele was shown to have little effect on H. bulbosum crossability compared to a significant effect on rye crossability. Tests with tetrasomic and nulli-tetrasomic lines of 'Chinese Spring' indicated that the kr allele is 'null' or inactive in promoting crossability while the Kr allele is active in reducing crossability to both rye and H. bulbosum. Thus, extra doses of the kr allele do not increase rye or H. bulbosum crossability in the presence of the corresponding Kr allele. [ABSTRACT FROM AUTHOR]

The pattern of follicular growth and the timing of the initiation of a fixed-time artifical insemination (TAI) protocols, relative to the stage of the estrous cycle, influence the conception rate in heifers. The objective of this experiment was to determine the effect of incorporating a supplemental GnRH injection into a CIDR-based TAI protocol on conception rate of heifers. Beef replacement heifers (n = 192) were paired by body condition score and body weight, and received a CIDR insert at random stages of the estrous cycle (d 0). On the same day, heifers were assigned randomly to receive either a single dose of 100 ug of GnRH (GnRH-CIDR; n = 94) or physiological saline (Sal-CIDR; n = 98). On d 7, the CIDR was removed and all heifers received 25 mg PGF. Forty eight h later (d 9), all heifers were administered GnRH (100 ug) and received AI by a single technician. Pregnancy was diagnosed by ultrasound 35 d after AI. Blood samples were collected on d -7, 0, 7, and 9 and analyzed for progesterone (P4) concentrations. There was no difference (P = 0.46) in the proportion of anovular heifers between groups (Sal-CIDR = 97.8% vs. GnRH-CIDR = 97.8%). Serum P4 was similar between groups on d 0, but was greater (P < 0.05) for the GnRH-CIDR than the Sal-CIDR on d 7. Moreover, there was a tendency for greater proportion of heifers from the GnRH-CIDR group to have P4 > 1.3 ng/ml on d 9 (GnRH-CIDR = 23.6% vs Sal-CIDR = 14%; P = 0.11), resulting in a smaller (P =0.11) synchronization rate in GnRH-CIDR compared with Sal-CIDR (76.4% vs 86%). However, conception rate at 35 d after AI was not affected (P = 0.52) by synchronization treatment (Sal-CIDR = 58.9% vs GnRHCIDR = 55.9%). The results of this experiment indicate that GnRH administration at CIDR insertion did not affect conception rates when a CIDR-PGF-GnRH fixed-time AI protocol was used in beef heifers. [ABSTRACT FROM AUTHOR]