Ring‐billed (Larus delawarensis) and herring (L. argentatus) gulls are numerous and widespread in North America. These gulls rank among the top 9 species for risk of bird‐aircraft collisions ...(hereafter strikes). The ubiquitous presence of gulls in urban coastal environments, including rooftop nesting behavior, are factors impacting strike risk. Our purpose was to assess gull response to a small uncrewed aircraft system (UAS) in hazing flights at night during the nest‐building phase. We hypothesized that nocturnal UAS operation, like nocturnal predator disturbance, might reduce gull numbers and, thus, strike risk to aircraft. In spring 2021, we conducted UAS treatments over target roofs at least once every hour from 2000 until 0200, weather permitting, for 15 min and over a 14‐day period for each site. The UAS flew directly above (~4 m) and then descended (~4 m/s) within 1 m of loafing gulls. No gulls interacted with the UAS and most flushed within 6 minutes. Generally, the first treatment of a night dispersed all gulls (min–max = 1–130 individuals) from the target roof for an extended period. Our operations were often grounded because of weather and our gull response data were limited because of few individuals present. We discuss our observations with particular attention to feasibility and possible implications such as shifting birds to other sites which, potentially, could be counterproductive for management.
We conducted nocturnal UAS hazing flights at two rooftop gull nesting colonies during the nest material gathering phase to reduce gull numbers in order to prevent bird‐aircraft collisions. No gulls interacted with the UAS and most flushed within 6 minutes from the rooftops. Our operations were affected by logistics, gull rooftop use, and weather.
While the high-entropy wind (HEW) of Type II supernovae remains one of the more promising sites for the rapid neutron-capture (r-) process, hydrodynamic simulations have yet to reproduce the ...astrophysical conditions under which the latter occurs. We have performed large-scale network calculations within an extended parameter range of the HEW, seeking to identify or to constrain the necessary conditions for a full reproduction of all r-process residuals N r, = N -N s, by comparing the results with recent astronomical observations. A superposition of weighted entropy trajectories results in an excellent reproduction of the overall N r, pattern beyond Sn. For the lighter elements, from the Fe group via Sr-Y-Zr to Ag, our HEW calculations indicate a transition from the need for clearly different sources (conditions/sites) to a possible co-production with r-process elements, provided a range of entropies are contributing. This explains recent halo-star observations of a clear noncorrelation of Zn and Ge and a weak correlation of Sr-Zr with heavier r-process elements. Moreover, new observational data on Ru and Pd also seem to confirm a partial correlation with Sr as well as the main r-process elements (e.g., Eu).
A major challenge in interpreting genome sequences is understanding how the genome encodes the information that specifies when and where a gene will be expressed. The first step in this process is ...the identification of regions of the genome that contain regulatory information. In higher eukaryotes, this cis-regulatory information is organized into modular units cis-regulatory modules (CRMs) of a few hundred base pairs. A common feature of these cis-regulatory modules is the presence of multiple binding sites for multiple transcription factors. Here, we evaluate the extent to which the tendency for transcription factor binding sites to be clustered can be used as the basis for the computational identification of cis-regulatory modules. By using published DNA binding specificity data for five transcription factors active in the early Drosophila embryo, we identified genomic regions containing unusually high concentrations of predicted binding sites for these factors. A significant fraction of these binding site clusters overlap known CRMs that are regulated by these factors. In addition, many of the remaining clusters are adjacent to genes expressed in a pattern characteristic of genes regulated by these factors. We tested one of the newly identified clusters, mapping upstream of the gap gene giant (gt), and show that it acts as an enhancer that recapitulates the posterior expression pattern of gt.
Fission plays an important role in the r-process which is responsible not only for the yields of transuranium isotopes, but may have a strong influence on the formation of the majority of heavy ...nuclei due to fission recycling. We present calculations of beta-delayed and neutron-induced fission rates, taking into account different fission barriers predictions and mass formulae. It is shown that an increase of fission barriers results naturally in a reduction of fission rates, but that nevertheless fission leads to the termination of the r-process. Furthermore, it is discussed that the probability of triple fission could be high for
A
>
260
and have an effect on the formation of the abundances of heavy nuclei. Fission after beta-delayed neutron emission is discussed as well as different aspects of the influence of fission upon r-process calculations.
We present nuclear reaction network calculations to investigate the influence of nuclear structure on the rp-process between Ge and Sn in various scenarios. Due to the lack of experimental data for ...neutron-deficient nuclei in this region, we discuss currently available model predictions for nuclear masses and deformations as well as methods of calculating reaction rates (Hauser-Feshbach) and β-decay rates (QRPA and shell model). In addition, we apply a valence nucleon (
N
p
N
n) correlation scheme for the prediction of masses and deformations. We also describe the calculations of 2p-capture reactions, which had not been considered before in this mass region. We find that in X-ray bursts 2p-capture reactions accelerate the reaction flow into the
Z ≥ 36 region considerably. Therefore, the rp-process in most X-ray bursts does not end in the
Z = 32–36 region as previously assumed and overproduction factors of 10
7–10
8 are reached for some light p-nuclei in the
A = 80–100 region. This might be of interest in respect of the yet unexplained large observed solar system abundances of these nuclei. Nuclei in this region can also be produced via the rp-proces in accretion disks around low mass black holes. Our results indicate that the rp-process energy production in the
Z > 32 region cannot be neglected in these scenarios. We discuss in detail the influence of the various nuclear structure input parameters and their current uncertainties on these results. It turns out that rp-process nucleosynthesis is mainly determined by nuclear masses and β-decay rates of nuclei along the proton drip line. We present a detailed list of nuclei for which mass or β-decay rate measurements would be crucial to further constrain the models.
>bold<>italic<Objective:>/italic<>/bold< To present a case of Hashimoto encephalopathy as a complication of autoimmune thyroiditis. >bold<>italic<Clinical Presentation and ...Intervention:>/italic<>/bold< A previously healthy 56-year-old female presented with rapidly progressive cognitive decline and visual hallucinations. Being a diagnosis of exclusion, Hashimoto encephalopathy required an extensive laboratory and diagnostic workup, which was done over the course of a 15-day hospitalization. The patient recovered after initial treatment with intravenous methylprednisolone and was then switched to prednisone p.o. >bold<>italic<Conclusion:>/italic<>/bold< This case report illustrates the importance of awareness for Hashimoto encephalopathy, as it remains one of the few easily treatable and reversible causes of rapid cognitive decline.
We herein describe a new synthesis of
N-(7-indazolyl)benzenesulfonamide derivatives. These compounds were evaluated for their antiproliferative activities toward L1210 murine leukemia cells. One of ...them, 4-methoxy-
N-(3-chloro-7-indazolyl)benzenesulfonamide, was identified as the most potent with an IC
50 of 0.44
μM.
We report on a detailed abundance analysis of two strongly r-process enhanced, very metal-poor stars newly discovered in the HERES project, CS 29491-069 (Fe/H = -2.51, r/Fe = +1.1) and HE 1219-0312 ...(Fe/H = -2.96, r/Fe = +1.5). The analysis is based on high-quality VLT/UVES spectra and MARCS model atmospheres. We detect lines of 15 heavy elements in the spectrum of CS 29491-069, and 18 in HE 1219-0312; in both cases including the Th II 4019 angstrom line. The heavy-element abundance patterns of these two stars are mostly well-matched to scaled solar residual abundances not formed by the s-process. We also compare the observed pattern with recent high-entropy wind (HEW) calculations, which assume core-collapse supernovae of massive stars as the astrophysical environment for the r-process, and find good agreement for most lanthanides. The abundance ratios of the lighter elements strontium, yttrium, and zirconium, which are presumably not formed by the main r-process, are reproduced well by the model. Radioactive dating for CS 29491-069 with the observed thorium and rare-earth element abundance pairs results in an average age of 9.5 Gyr, when based on solar r-process residuals, and 17.6 Gyr, when using HEW model predictions. Chronometry seems to fail in the case of HE 1219-0312, resulting in a negative age due to its high thorium abundance. HE 1219-0312 could therefore exhibit an overabundance of the heaviest elements, which is sometimes called an "actinide boost".
Osteoporosis is a common problem in orthopedic surgery. The purpose of this review of the literature was to examine whether osteoporosis is also an important factor in patient treatment in the field ...of craniomaxillofacial surgery. Emphasis was given to the consequences of osteoporosis for the maxilla and mandible, the influence of osteoporosis on fracture treatment, the use of dental implants, the importance of soft tissues and the effect of osteoporosis therapies. It was found that osteoporosis does affect the bones of the skull. The effect of osteoporosis on treatment, however, is controversial and necessitates better ways of quantifying bone loss. Large inter-individual and site-specific differences in bone density, as well as other effects such as removal of teeth, periodontitis, implant insertion, augmentation procedures and altered loading with dystrophic consequences need to be considered in future studies. Special attention should be given to osteoporosis during fracture treatment.
Total Synthesis of (+)-Cyanthiwigin U Pfeiffer, Matthew W. B; Phillips, Andrew J
Journal of the American Chemical Society,
04/2005, Letnik:
127, Številka:
15
Journal Article
Recenzirano
A concise total synthesis of the tricyclic terpene cyanthiwigin U has been accomplished in 12 steps and 17% overall yield. The key step of the synthesis is a two-directional tandem metathesis ...reaction that forms the cycloheptaeindene core from a readily available bicyclo2.2.2octene.
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