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81.
Jessica E. Howell Ann E. McKellar Richard H. M. Espie Christy A. Morrissey 《Ibis》2020,162(2):535-547
High-quality staging sites are critical for long-distance migratory shorebirds to rest and refuel but are under threat from human development, including expansion of wind energy projects. However, predicting migration timing and movements in relation to weather conditions at staging sites can increase our understanding and mitigate effects of wind turbine collisions. Here we assessed northward migration timing and orientation in relation to environmental conditions at an inland staging area in Saskatchewan, Canada, with active and proposed wind energy developments. The area is known to host ~25% of North America's Sanderling Calidris alba population and 16 other Arctic-breeding migrant shorebird species. We quantified arrival and departure time of day in relation to weather using data from 140 of 237 Sanderlings radiotagged locally and at a southern staging site in the Gulf of Mexico with the Motus Wildlife Tracking System (April–June, 2015–2017). Although Sanderling arrival times were not related to time of day or weather, departures were more likely at sunset in winds blowing towards the northwest at intermediate speeds (<22 km/h). Departure flights were also primarily oriented north-northwest in the direction of a proposed wind energy development site at a mean ground speed of 21.4 m/s. Based on published climb rates and flight speed data, we estimated that shorebirds needed between 2 and 14 km setback distance to clear maximum turbine heights of 165 m. Given that departure events were predictable in time and space, adaptive mitigation may be useful for planning wind energy developments while reducing risk for staging Arctic-breeding shorebirds. 相似文献
82.
One biggest obstacle in molecular programming is that there is still no direct method to compile any existed mathematical model into biochemical reaction in order to solve a computational problem. In this paper, the implementation of DNA Strand Displacement system based on nature-inspired computation is observed. By using the Immune Network Theory and Chemical Reaction Network, the compilation of DNA-based operation is defined and the formulation of its mathematical model is derived. Furthermore, the implementation on this system is compared with the conventional implementation by using silicon-based programming. From the obtained results, we can see a positive correlation between both. One possible application from this DNA-based model is for a decision making scheme of intelligent computer or molecular robot. 相似文献
83.
Capturing or diverting the disease carrying vector from humans can reduce the transmission of vector borne diseases such as leishmaniasis. The use of animals that act as dead-end hosts to relieve the vector (sandfly) bites on humans is called zooprophylaxis. However, as the number of blood meal providers especially domestic animals increases, the sandflies enhanced availability of blood meals will improve its number and survival, thereby countering the impact of diverting bites from humans. Thus, the transmission model exhibits the structure of a feedback loop characterizing complex dynamic systems. In order to rigorously assess the effect of zooprophylaxis, we propose a system dynamic model for zoonotic cutaneous leishmaniasis transmission with 3 blood-meal hosts: domestic animals, humans, and a reservoir (rodents). In this context, a simulation study of the proposed model with a follow-up period of 1000 days was performed. 相似文献
84.
Junying Liu Xiping YanQingqing Li Guosong WangHehe Liu Jiwen WangLiang Li Xiaohui DuChunchun Han Hua He 《Journal of thermal biology》2013
Avian embryos are easily influenced by their environment during incubation. Previous studies have demonstrated that incubation temperature changes could influence muscle development and body weight, which subsequently determine the adult phenotype. The objective of this study was to investigate whether the development of immune organs in ducklings could be influenced by thermal manipulation during the middle stage of incubation. To evaluate this hypothesis, a control group was incubated under a normal temperature from E11 to E24, while the incubation temperature of the experimental group was increased by 1 °C. Our results indicated that slight changes in the incubation temperature significantly repressed the bursa of Fabricius index of the duck embryo on E25 (F1, 58=122.51, P<0.0001) and significantly repressed the spleen index of neonatal ducklings (F1, 58=74.38, P<0.0001). At 0 day posthatching (dph) and 14 dph, ducklings hatched from eggs incubated under the higher temperature had a lower percentage of globulin than the control group (F1, 10=19.97, P=0.0111; F1, 10=9.8, P=0.0352). The IFN-γ concentration of ducklings at 14 dph displayed the same trend (F1, 10=284.49, P<0.0001). These results suggested that thermal manipulation during the middle stage of incubation had a repressive effect on the development of immune organs and reduced the concentrations of serum globulin and IFN-γ. These results demonstrated that the subtle alteration of incubation temperature may weaken ducklings' immunity. 相似文献
85.
Inesse Ben-Abdallah-Bouhjar Soumya Mougou-Zerelli Hanene Hannachi Hela Ben-Khelifa Najla Soyah Audrey Labalme Damien Sanlaville Hatem Elghezal Ali Saad 《Gene》2013
Partial duplication of 11q is related to several malformations like growth retardation, intellectual disability, hypoplasia of corpus callosum, short nose, palate defects, cardiac, urinary tract abnormalities and neural tube defects. We have studied the clinical and molecular characteristics of a patient with severe intellectual disabilities, dysmorphic features, congenital inguinal hernia and congenital cerebral malformation which is referred to as cytogenetic exploration. We have used FISH and array CGH analysis for a better understanding of the double chromosomic aberration involving a 7p microdeletion along with a partial duplication of 11q due to adjacent segregation of a paternal reciprocal translocation t(7;11)(p22;q21) revealed after banding analysis. The patient's karyotype formula was: 46,XY,der(7)t(7;11)(p22;q21)pat. FISH study confirmed these rearrangement and array CGH technique showed precisely the loss of at least 140 Kb on chromosome7p22.3pter and 33.4 Mb on chromosome11q22.1q25. Dysmorphic features, severe intellectual disability and brain malformations could result from the 11q22.1q25 trisomy. Our study provides an additional case for better understanding and delineating the partial duplication 11q. 相似文献
86.
《Chronobiology international》2013,30(6):382-388
Binding of melatonin by rat thymus membranes exhibited diurnal changes. Binding increased during the daytime and reached maximal values before entering the dark period. Then, binding decreased rapidly during the dark phase. In rats kept in light at night, binding of [125I]melatonin by membranes was significantly higher than in animals that entered the normal dark period. Neonatal pinealectomy, which suppresses the circadian rhythm of melatonin, led to an increase in melatonin binding of 106%. Moreover, in animals maintained under continuous light exposure, which corresponds to functional pinealectomy, binding of melatonin by thymus membranes also increased in a time-dependent manner. The results support the hypothesis of a regulatory role of melatonin in the thymus in which melatonin downregulates its own binding sites. 相似文献
87.
P. Pévet L. Agez B. Bothorel M. Saboureau F. Gauer V. Laurent 《Chronobiology international》2013,30(1-2):39-51
In mammals, the complex interaction of neural, hormonal, and behavioral outputs from the suprachiasmatic nucleus (SCN) drives circadian expression of events, either directly or through coordination of the timing of peripheral oscillators. Melatonin, one of the endocrine output signals of the clock, provides the organism with circadian information and can be considered as an endogenous synchronizer, able to stabilize and reinforce circadian rhythms and to maintain their mutual phase‐relationship at the different levels of the circadian network. Moreover, exogenous melatonin, through an action on the circadian clock, affects all levels of the circadian network. The molecular mechanisms underlying this chronobiotic effect have also been investigated in rats. REV‐ERB α seems to be the initial molecular target. 相似文献
88.
Rolando Perdomo-Morales Vivian Montero-Alejo Gerardo Corzo Vladimir Besada Yamile Vega-Hurtado Yamile González-González Erick Perera Marlene Porto-Verdecia 《The Journal of biological chemistry》2013,288(44):31867-31879
The melanization reaction promoted by the prophenoloxidase-activating system is an essential defense response in invertebrates subjected to regulatory mechanisms that are still not fully understood. We report here the finding and characterization of a novel trypsin inhibitor, named panulirin, isolated from the hemocytes of the spiny lobster Panulirus argus with regulatory functions on the melanization cascade. Panulirin is a cationic peptide (pI 9.5) composed of 48 amino acid residues (5.3 kDa), with six cysteine residues forming disulfide bridges. Its primary sequence was determined by combining Edman degradation/N-terminal sequencing and electrospray ionization-MS/MS spectrometry. The low amino acid sequence similarity with known proteins indicates that it represents a new family of peptidase inhibitors. Panulirin is a competitive and reversible tight-binding inhibitor of trypsin (Ki = 8.6 nm) with a notable specificity because it does not inhibit serine peptidases such as subtilisin, elastase, chymotrypsin, thrombin, and plasmin. The removal of panulirin from the lobster hemocyte lysate leads to an increase in phenoloxidase response to LPS. Likewise, the addition of increasing concentrations of panulirin to a lobster hemocyte lysate, previously depleted of trypsin-inhibitory activity, decreased the phenoloxidase response to LPS in a concentration-dependent fashion. These results indicate that panulirin is implicated in the regulation of the melanization cascade in P. argus by inhibiting peptidase(s) in the pathway toward the activation of the prophenoloxidase enzyme. 相似文献
89.
Ruben Van der Meeren Yurong Wen Patrick Van Gelder Jan Tommassen Bart Devreese Savvas N. Savvides 《The Journal of biological chemistry》2013,288(2):1214-1225
The type II secretion system is a multiprotein assembly spanning the inner and outer membranes in Gram-negative bacteria. It is found in almost all pathogenic bacteria where it contributes to virulence, host tissue colonization, and infection. The exoproteins are secreted across the outer membrane via a large translocation channel, the secretin, which typically adopts a dodecameric structure. These secretin channels have large periplasmic N-terminal domains that reach out into the periplasm for communication with the inner membrane platform and with a pseudopilus structure that spans the periplasm. Here we report the crystal structure of the N-terminal periplasmic domain of the secretin XcpQ from Pseudomonas aeruginosa, revealing a two-lobe dimeric assembly featuring parallel subunits engaging in well defined interactions at the tips of each lobe. We have employed structure-based engineering of disulfide bridges and native mass spectrometry to show that the periplasmic domain of XcpQ dimerizes in a concentration-dependent manner. Validation of these insights in the context of cellular full-length XcpQ and further evaluation of the functionality of disulfide-linked XcpQ establishes that the basic oligomerization unit of XcpQ is a dimer. This is consistent with the notion that the dodecameric secretin assembles as a hexamer of dimers to ensure correct projection of the N-terminal domains into the periplasm. Therefore, our studies provide a key conceptual advancement in understanding the assembly principles and dynamic function of type II secretion system secretins and challenge recent studies reporting monomers as the basic subunit of the secretin oligomer. 相似文献
90.
Ana Konvalinka Joyce Zhou Apostolos Dimitromanolakis Andrei P. Drabovich Fei Fang Susan Gurley Thomas Coffman Rohan John Shao-Ling Zhang Eleftherios P. Diamandis James W. Scholey 《The Journal of biological chemistry》2013,288(34):24834-24847
Angiotensin II (AngII), the major effector of the renin-angiotensin system, mediates kidney disease progression by signaling through the AT-1 receptor (AT-1R), but there are no specific measures of renal AngII activity. Accordingly, we sought to define an AngII-regulated proteome in primary human proximal tubular cells (PTEC) to identify potential AngII activity markers in the kidney. We utilized stable isotope labeling with amino acids (SILAC) in PTECs to compare proteomes of AngII-treated and control cells. Of the 4618 quantified proteins, 83 were differentially regulated. SILAC ratios for 18 candidates were confirmed by a different mass spectrometry technique called selected reaction monitoring. Both SILAC and selected reaction monitoring revealed heme oxygenase-1 (HO-1) as the most significantly up-regulated protein in response to AngII stimulation. AngII-dependent regulation of the HO-1 gene and protein was further verified in PTECs. To extend these in vitro observations, we overlaid a network of significantly enriched gene ontology terms from our AngII-regulated proteins with a dataset of differentially expressed kidney genes from AngII-treated wild type mice and AT-1R knock-out mice. Five gene ontology terms were enriched in both datasets and included HO-1. Furthermore, HO-1 kidney expression and urinary excretion were reduced in AngII-treated mice with PTEC-specific AT-1R deletion compared with AngII-treated wild-type mice, thus confirming AT-1R-mediated regulation of HO-1. Our in vitro approach identified novel molecular markers of AngII activity, and the animal studies demonstrated that these markers are relevant in vivo. These interesting proteins hold promise as specific markers of renal AngII activity in patients and in experimental models. 相似文献