X-Ray diffraction study of pyridine boron trichloride

Thesis (M.A.)--Boston UniversityThe x-ray diffraction study of pyridine-boron trichloride undertaken here constitutes the beginning of a structure determination which will eventually result in a complete knowledge of bond distances and bond angles within the molecule and knowledge of the packing of molecules within the crystal. The 1:1 addition compound pyridine-boron trichloride was first reported by Gerrard and Lappert. Greenwood and Wade were among the first to study the physical properties of pyridine-boron trichloride. In the absence of direct evidence as to what ions are present and the extent of dissociation, four possible structures were inferred for pyridine-BCl3. [Py2BCl2]+[BCl4]- was considered the most favorable for the molten state. However, a detailed examination of the infrared spectrum of the solid shows that the structure is probably more consistent with the formula C5H5N -> BCl3. This was also the structure found by Zvonkova for pyridine-boron trifluoride [TRUNCATED

A Gaussian Wavefunction for the Isoelectronic Sequence of Two-Electron Homonuclear Diatomic Molecules

The Gaussian wavefunctions recently reported by Kim an d Hirschfelder were found to be in error due t o incorrect formulas for two integrals . The interaction potentials calculated in terms of t he corrected wave-f unctions are found to be in reasonable accord with the exact results of Kolos and Wolniewicz. near the equilibrium separation but in relatively poor accord at moderately large internuclear separations . A scaling of the energy and length to fit the exact curve at its minimum did not ameliorate the situation . For the H2 isoelectronic sequence it was found that scaling the H2 optimized orbital exponent by z and the internuclear distance by Z allowed the prediction of the fully optimized energy of other members of the sequence to within ( at worst ) 1%

Independence day: Post-fledging movements and behavior of adult Eastern Towhees (\u3cem\u3ePipilo erythrophthalmus\u3c/em\u3e) in landscapes managed for American Woodcock (\u3cem\u3eScolopax minor\u3c/em\u3e)

Umbrella species management offers a potential solution to the financial and logistical challenges of managing for the many declining species in early-successional forests, a habitat that is also critical for many mature and young forest songbird species during the post-fledging and post-breeding period. We investigated the movements of adult Eastern Towhees (Pipilo erythrophthalmus) during the post-fledging period in 4 km2 landscapes managed for American Woodcock (Scolopax minor), a popular umbrella species candidate for young forest management. Home range size (mean = 2.8 ha, SE 0.33) did not differ during the post-fledging period between adult towhees inhabiting landscapes designated as high-likelihood (HL) or low-likelihood (LL) of woodcock use. Adults moved distances of ∼37–47 m per day during the first 3 weeks of the post-fledging period and this did not differ between the 2 landscapes. In contrast, once their young became independent, adults moved longer distances in HL compared to LL landscapes (49.5 m [SE 2.9] and 36.7 m [SE 3.6], respectively) and these distances increased with home range size and patch size. Landscape features within 100 m of the towhee home range best explained variation in towhee movement distance. Young forest habitat was also the predominant forest type used by adult towhees caring for fledglings throughout the post-fledging period. These results suggest that early successional forest management for woodcock can provide effective breeding habitat for towhees, but likely at a smaller spatial scale than typically managed for woodcock

Northern Saw-whet Owl Autumn Migration in Eastern Nebraska: Results from a Three-year Banding Study

Prior to 2019, records of NSWOs in Nebraska during fall were limited. There were fewer than five accepted reports in eastern Nebraska since the 1950s (Silcock and Jorgensen, 2021). The Hitchcock banding station along the Missouri River bluffs in nearby western Iowa has captured, banded, and released 20-50 birds during autumn migration for a number of years (J. Toll, personal communication). Furthermore, a single season banding study in central Nebraska during fall 2004 captured 14 NSWOs (Kim 2005), suggesting the species may migrate annually over much of the state in fall, or at least in more years than previously thought. This is despite the relative lack of continuous forested habitat in the eastern and central part of the state and extensive areas of agricultural land cover. However, the absence of any systematic effort to detect this species over multiple years, especially away from the Missouri River, renders such conclusions speculative. To address information gaps, we conducted targeted NSWO banding efforts in the vicinity of Lincoln, Nebraska, for three consecutive years in 2019, 2020, and 2021. Our objectives were to determine 1) whether NSWOs migrate through this area regularly in fall, 2) the phenology of migration through our area, and 3) whether NSWO age classes vary by year. Our results should clarify and define the status of NSWOs’ fall movements in eastern Nebraska

A study of the moving flame effect in three dimensions and its implications for the general circulation of the upper atmosphere of Venus

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Meteorology and Physical Oceanography, 1982.Microfiche copy available in Archives and Science.Bibliography: leaves 236-239.by Stephen Brenner.Ph.D

Incorrectly Aged, Identified and Classified: Revisiting Nebraska’s 1968 ‘Barnacle Goose’ Record

On 2 November 1968 in northeastern Otoe County, Nebraska, Milton Muncie harvested a bird (herein referred to as the 1968 specimen), subsequently identified as an immature Barnacle Goose (Branta leucopsis), from a flock of about 40 Cackling Geese (Branta hutchinsii; Cortelyou 1969). The occurrence was reported not only as the first record of a Barnacle Goose for Nebraska, but also the first record for the North American Interior and West (Cortelyou 1969). Cortelyou’s (1969) brief article also included a photograph of the mounted specimen. At the time and when subsequently reviewed by various authors, the identity of the 1968 specimen as a Barnacle Goose was not a matter of debate. Questions about its provenance, however, led authors (Bray et al. 1986, Sharpe et al. 2001) to consider the species’ occurrence as a wild bird in the state to be unproven, thus “hypothetical”. Bray et al. (1986) noted an immature in fall was a likely age class and period for a genuine wild vagrant, but considered the Otoe County specimen an escapee, citing Ryff (1984). Johnsgard (2018) also acknowledged the possibility the 1968 specimen could be a true vagrant, referring to it as “apparently wild”. Barnacle Goose has subsequently been reported four times in the state, but none of the reports are as welldocumented as the 1968 specimen. Thus, no records have been accepted and Barnacle Goose does not appear on the Official List of the Birds of Nebraska (Brogie 2009)

Diminishing Returns: Results of Black Rail Surveys in Nebraska

The uncertain status of the Black Rail in Nebraska is problematic. Different authors have interpreted existing reports differently resulting in varying conclusions about the species’ status. The exercise of deciphering the limited details of existing reports and litigating their credibility is of little value. The Black Rail is now a threatened species and there is almost no published information on whether it occurs regularly in Nebraska. Furthermore, the species has not been searched for in any consistent form or systematic manner. Without information and understanding about the species’ occurrence, taking actions to benefit and protect this species will undoubtedly be difficult for government and non-governmental agencies or for interested individuals who want to do so. Since 2013, the Nongame Bird Program at the Nebraska Game and Parks Commission has conducted surveys focused on secretive marh birds throughout the state. Although up to eight species were targeted in these specialized surveys, a primary objective was to determine the presence/absence and/or abundance of Black Rails. Here, we report the results from our survey efforts to detect Black Rails in Nebraska

p53 Activation by Knockdown Technologies

Morpholino phosphorodiamidate antisense oligonucleotides (MOs) and short interfering RNAs (siRNAs) are commonly used platforms to study gene function by sequence-specific knockdown. Both technologies, however, can elicit undesirable off-target effects. We have used several model genes to study these effects in detail in the zebrafish, Danio rerio. Using the zebrafish embryo as a template, correct and mistargeting effects are readily discernible through direct comparison of MO-injected animals with well-studied mutants. We show here indistinguishable off-targeting effects for both maternal and zygotic mRNAs and for both translational and splice-site targeting MOs. The major off-targeting effect is mediated through p53 activation, as detected through the transferase-mediated dUTP nick end labeling assay, acridine orange, and p21 transcriptional activation assays. Concurrent knockdown of p53 specifically ameliorates the cell death induced by MO off-targeting. Importantly, reversal of p53-dependent cell death by p53 knockdown does not affect specific loss of gene function, such as the cell death caused by loss of function of chordin. Interestingly, quantitative reverse-transcriptase PCR, microarrays and whole-mount in situ hybridization assays show that MO off-targeting effects are accompanied by diagnostic transcription of an N-terminal truncated p53 isoform that uses a recently recognized internal p53 promoter. We show here that MO off-targeting results in induction of a p53-dependent cell death pathway. p53 activation has also recently been shown to be an unspecified off-target effect of siRNAs. Both commonly used knockdown technologies can thus induce secondary but sequence-specific p53 activation. p53 inhibition could potentially be applicable to other systems to suppress off-target effects caused by other knockdown technologies

Willingness to Use a Wearable Device Capable of Detecting and Reversing Overdose Among People Who Use Opioids in Philadelphia

Background: The incidence of opioid-related overdose deaths has been rising for 30 years and has been further exacerbated amidst the COVID-19 pandemic. Naloxone can reverse opioid overdose, lower death rates, and enable a transition to medication for opioid use disorder. Though current formulations for community use of naloxone have been shown to be safe and effective public health interventions, they rely on bystander presence. We sought to understand the preferences and minimum necessary conditions for wearing a device capable of sensing and reversing opioid overdose among people who regularly use opioids. Methods: We conducted a combined cross-sectional survey and semi-structured interview at a respite center, shelter, and syringe exchange drop-in program in Philadelphia, Pennsylvania, USA during the COVID-19 pandemic in August and September 2020. The primary aim was to explore the proportion of participants who would use a wearable device to detect and reverse overdose. Preferences regarding designs and functionalities were collected via a questionnaire with items having Likert-based response options and a semi-structured interview intended to elicit feedback on prototype designs. Independent variables included demographics, opioid use habits, and previous experience with overdose. Results: A total of 97 adults with an opioid-use history of at least 3 months were interviewed. A majority of survey participants (76%) reported a willingness to use a device capable of detecting an overdose and automatically administering a reversal agent upon initial survey. When reflecting on the prototype, most respondents (75.5%) reported that they would wear the device always or most of the time. Respondents indicated discreetness and comfort as important factors that increased their chance of uptake. Respondents suggested that people experiencing homelessness and those with low tolerance for opioids would be in greatest need of the device. Conclusions: The majority of people sampled with a history of opioid use in an urban setting were interested in having access to a device capable of detecting and reversing an opioid overdose. Participants emphasized privacy and comfort as the most important factors influencing their willingness to use such a device. Trial Registration: NCT0453059