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61.
62.
Forest P. Hayes Joshua J. Millspaugh Eric J. Bergman Ragan M. Callaway Chad J. Bishop 《The Journal of wildlife management》2022,86(2):e22175
Across much of North America, populations of moose (Alces alces) are declining because of disease, predation, climate change, and anthropogenic-driven habitat loss. Contrary to this trend, populations of moose in Colorado, USA, have continued to grow. Studying successful (i.e., persistent or growing) populations of moose can facilitate continued conservation by identifying habitat features critical to persistence of moose. We hypothesized that moose using habitat with higher quality willow (Salix spp.) would have a higher probability of having a calf-at-heel (i.e., calving success). We evaluated moose calving success using repeated ground observations of collared individuals with calves in an occupancy model framework to account for detection probability. We then evaluated the impact of willow habitat quality and nutrition on moose calving success by studying 2 spatially segregated populations of moose in Colorado. Last, we evaluated correlations between willow characteristics (browse intensity, height, cover, leaf length, and species) and willow nutrition (dry matter digestibility [DMD]) to assess the utility of using those characteristics to assess willow nutrition. We found willow height and cover had a high probability of being positively associated with higher individual-level calving success. Willow DMD, browse intensity, and leaf length were not predictive of individual moose calving success; however, the site with higher mean DMD consistently had higher mean estimates of calving success for the same year. Our results suggest surveying DMD is likely not a useful metric for assessing differences in calving success of individual moose but may be of use at population levels. Further, the assessment of willow morphology and density may be used to identify areas that support higher levels of moose calving success. 相似文献
63.
64.
Arabidopsis mitochondria are predicted to contain three acyl carrier proteins (ACPs). These small proteins are involved in fatty acid
and lipoic acid synthesis in other organisms and have been previously reported to be subunits of respiratory Complex I in
mitochondria in mammals, fungi and plants. Recently, the mammalian mitochondrial ACP (mtACP) has been shown to be largely
a soluble matrix protein but also to be minimally associated with Complex I (Cronan et al. 2005), consistent with its involvement in synthesis of lipoic acid for TCA cycle decarboxylating dehydrogenases in the matrix
but contrary to earlier claims it was primarily a Complex I subunit. We have investigated the localization of the ACPs in
Arabidopsis mitochondria. Evidence is presented that mtACP1 and mtACP2 dominate the ACP composition in Arabidopsis mitochondria, and both are present in the mitochondrial matrix rather than in the membrane. No significant amounts of mtACPs
were detected in Complex I isolated by blue native gel electrophoresis, rather mtACPs were detected at low molecular mass
in the soluble fraction, showing that in A. thaliana mtACPs are predominately free soluble matrix proteins. 相似文献
65.
Steven P. Govek Celine Bonnefous Jackaline D. Julien Johnny Y. Nagasawa Mehmet Kahraman Andiliy G. Lai Karensa L. Douglas Anna M. Aparicio Beatrice D. Darimont Katherine L. Grillot James D. Joseph Joshua A. Kaufman Kyoung-Jin Lee Nhin Lu Michael J. Moon Rene Y. Prudente John Sensintaffar Peter J. Rix Nicholas D. Smith 《Bioorganic & medicinal chemistry letters》2019,29(3):367-372
Potent estrogen receptor ligands typically contain a phenolic hydrogen-bond donor. The indazole of the selective estrogen receptor degrader (SERD) ARN-810 is believed to mimic this. Disclosed herein is the discovery of ARN-810 analogs which lack this hydrogen-bond donor. These SERDs induced tumor regression in a tamoxifen-resistant breast cancer xenograft, demonstrating that the indazole NH is not necessary for robust ER-modulation and anti-tumor activity. 相似文献
66.
A Gdalyahu E Tring PO Polack R Gruver P Golshani MS Fanselow AJ Silva JT Trachtenberg 《Neuron》2012,75(1):121-132
Several models of associative learning predict that stimulus processing changes during association formation. How associative learning reconfigures neural circuits in primary sensory cortex to "learn" associative attributes of a stimulus remains unknown. Using 2-photon in vivo calcium imaging to measure responses of networks of neurons in primary somatosensory cortex, we discovered that associative fear learning, in which whisker stimulation is paired with foot shock, enhances sparse population coding and robustness of the conditional stimulus, yet decreases total network activity. Fewer cortical neurons responded to stimulation of the trained whisker than in controls, yet their response strength was enhanced. These responses were not observed in mice exposed to a nonassociative learning procedure. Our results define how the cortical representation of a sensory stimulus is shaped by associative fear learning. These changes are proposed to enhance efficient sensory processing after associative learning. 相似文献
67.
Ryan P. Bourbour Breanna L. Martinico Megan M. Crane Angus C. Hull Joshua M. Hull 《Ecology and evolution》2019,9(3):1452-1457
Complex coevolutionary relationships among competitors, predators, and prey have shaped taxa diversity, life history strategies, and even the avian migratory patterns we see today. Consequently, accurate documentation of prey selection is often critical for understanding these ecological and evolutionary processes. Conventional diet study methods lack the ability to document the diet of inconspicuous or difficult‐to‐study predators, such as those with large home ranges and those that move vast distances over short amounts of time, leaving gaps in our knowledge of trophic interactions in many systems. Migratory raptors represent one such group of predators where detailed diet studies have been logistically challenging. To address knowledge gaps in the foraging ecology of migrant raptors and provide a broadly applicable tool for the study of enigmatic predators, we developed a minimally invasive method to collect dietary information by swabbing beaks and talons of raptors to collect trace prey DNA. Using previously published COI primers, we were able to isolate and reference gene sequences in an open‐access barcode database to identify prey to species. This method creates a novel avenue to use trace molecular evidence to study prey selection of migrating raptors and will ultimately lead to a better understanding of raptor migration ecology. In addition, this technique has broad applicability and can be used with any wildlife species where even trace amounts of prey debris remain on the exterior of the predator after feeding. 相似文献
68.
Joshua Isaacson 《Evolution; international journal of organic evolution》2019,73(7):1492-1493
Species adapt to the selective pressures of novel environments. Here, Gleditsch and Sperry tested whether four nonnative frugivorous bird species on the Hawaiian island of O'ahu diverged morphologically from their ancestral populations. They found that all four species significantly diverged from populations in their native ranges, with a general trend of smaller body size and larger bills. These differences were likely due to a combination of adaptive and nonadaptive processes. 相似文献
69.
Tressia M. Dayton Karen A. Diefenbach Michelle L. Fuller Joshua Valtos Eric C. Niederhoffer 《Biometals》1996,9(2):131-137
Proteus mirabilis and Proteus vulgaris expressed a combination of superoxide dismutase (Sod) activities, which was assigned to FeSod1, FeSod2 and MnSod for P. mirabilis, and FeSod, MnSod and CuZnSod for P. vulgaris. Production of the Sod proteins was dependent on the availability of iron, whether cells were grown under anaerobiosis or aerobiosis and growth phase. Nalidixic acid and chloramphenicol inhibited cell growth and the iron- and dioxygen-dependent production of Sod. These results support the involvement of metal ions and redox status in the production of Proteus Sods. 相似文献
70.
Gosselin Luc E.; Megirian David; Rodman Joshua; Mueller Donna; Farkas Gaspar A. 《Journal of applied physiology》1997,83(4):1405
Gosselin, Luc E., David Megirian, Joshua Rodman, DonnaMueller, and Gaspar A. Farkas. Respiratory muscle reserve in ratsduring heavy exercise. J. Appl.Physiol. 83(4): 1405-1409, 1997.The extent towhich the respiratory pump muscles limit maximal aerobic capacity inquadrupeds is not entirely clear. To examine the effect of reducedrespiratory muscle reserve on aerobic capacity, whole bodypeak oxygen consumption(O2 peak) wasmeasured in healthy Sprague-Dawley rats before and after Sham,unilateral, or bilateral hemidiaphragm denervation (Dnv) surgery.O2 peak wasdetermined by using a graded treadmill running test.Hemidiaphragm paralysis was verified after testing byrecording the absence of electromyographic activity duringinspiration. Before surgery, O2 peak averaged 86, 87, and 92 ml · kg1 · min1for the Sham, unilateral, and bilateral Dnv groups, respectively. Twoweeks after surgery, there was no significant change inO2 peak foreither the Sham or unilateral Dnv group. However,O2 peak decreased~19% in the bilateral Dnv group 2 wk after surgery. These findingsstrongly suggest that the pulmonary system in rats is designed suchthat during heavy exercise, the remaining respiratory pump muscles areable to compensate for the loss of one hemidiaphragm, but not of both. 相似文献