2,498 research outputs found
Chemical reactivity of hydrogen, nitrogen, and oxygen atoms at temperatures below 100 deg K Final technical report, 1 Dec. 1962 - 31 Dec. 1965
Chemical reactivity of atomic hydrogen, nitrogen, and oxygen at cryogenic temperature
Chemical reactivity of hydrogen, nitrogen and oxygen atoms at temperatures below 100 deg K Fifth semiannual technical report
Chemical reactivity of hydrogen, nitrogen, and oxygen atoms at temperatures below 100 deg
Releasing Captive-Reared Masked Bobwhites for Population Recovery: A Review
Efforts to reestablish the endangered masked bobwhite (Colinus virginianus ridgwayi) to its former historic range have been a primary focus on the Buenos Aires National Wildlife Refuge (BANWR) since it was established in 1986. Prerelease conditioning techniques developed prior to refuge establishment continued to be utilized in an effort to improve postrelease survival of captive-reared masked bobwhite chicks. Foremost among these techniques was the use of wild Texas bobwhite ( C. v. texanus) males as foster parents. Texas foster parents were released with broods from 1985-1996. The efficacy of this technique was evaluated in 1994 using radio telemetry. Results suggested that postrelease survival of chicks was poor. Using an adaptive approach, prerelease protocols were modified over several years in an effort to improve postrelease survival among chicks. Since 1995. released chicks were monitored via radio telemetry and results of the modified releases indicated survival had improved. Though these results are preliminary and this study is ongoing, it appears that our modifications to prerelease conditioning may improve survival rates of captive-reared masked bobwhite chicks. The results of this research project may have implications for captive-reared quail release projects elsewhere
Evidence of Air and Surface Contamination with SARS-CoV-2 in a Major Hospital in Portugal
As the third wave of the COVID-19 pandemic hit Portugal, it forced the country to reintro-duce lockdown measures due to hospitals reaching their full capacities. Under these circumstances, environmental contamination by SARS-CoV-2 in different areas of one of Portugal’s major Hospitals was assessed between 21 January and 11 February 2021. Air samples (n = 44) were collected from eleven different areas of the Hospital (four COVID-19 and seven non-COVID-19 areas) using Coriolis® µ and Coriolis® Compact cyclone air sampling devices. Surface sampling was also performed (n = 17) on four areas (one COVID-19 and three non-COVID-19 areas). RNA extraction followed by a one-step RT-qPCR adapted for quantitative purposes were performed. Of the 44 air samples, two were positive for SARS-CoV-2 RNA (6575 copies/m3 and 6662.5 copies/m3, respectively). Of the 17 surface samples, three were positive for SARS-CoV-2 RNA (200.6 copies/cm2, 179.2 copies/cm2, and 201.7 copies/cm2, respectively). SARS-CoV-2 environmental contamination was found both in air and on surfaces in both COVID-19 and non-COVID-19 areas. Moreover, our results suggest that longer collection sessions are needed to detect point contaminations. This reinforces the need to remain cautious at all times, not only when in close contact with infected individuals. Hand hygiene and other standard transmission-prevention guidelines should be continuously followed to avoid nosocomial COVID-19. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Funding text 1: Acknowledgments: Priscilla Gomes da Silva thanks the Portuguese Foundation for Science and Technology–FCT for the financial support of her PhD work (2020.07806.BD, CRM: 0026504) contract through the DOCTORATES 4 COVID-19 program. Sofia I.V. Sousa thanks the Portuguese Foundation for Science and Technology (FCT) for the financial support of her work contract through the Scientific Employment Stimulus-Individual Call-CEECIND/02477/2017.; Funding text 2: Funding: This work was financially supported by Base Funding-UIDB/00511/2020 of the Laboratory for Process Engineering, Environment, Biotechnology and Energy–LEPABE—funded by national funds through the FCT/MCTES (PIDDAC)
Regulation of the tumour suppressor PDCD4 by miR-499 and miR-21 in oropharyngeal cancers
© 2016 Zhang et al. Background: The rates of oropharyngeal cancers such as tonsil cancers are increasing. The tumour suppressor protein Programmed Cell Death Protein 4 (PDCD4) has been implicated in the development of various human cancers and small RNAs such as microRNAs (miRNAs) can regulate its expression. However the exact regulation of PDCD4 by multiple miRNAs in oropharyngeal squamous cell carcinoma (SCC) is not well understood. Results: Using two independent oropharyngeal SCC cohorts with a focus on the tonsillar region, we identified a miRNA profile differentiating SCC tissue from normal. Both miR-21 and miR-499 were highly expressed in tonsil SCC tissues displaying a loss of PDCD4. Interestingly, expression of the miRNA machinery, Dicer1, Drosha, DDX5 (Dead Box Helicase 5) and DGCR8 (DiGeorge Syndrome Critical Region Gene 8) were all elevated by greater than 2 fold in the tonsil SCC tissue. The 3'UTR of PDCD4 contains three binding-sites for miR-499 and one for miR-21. Using a wild-type and truncated 3'UTR of PDCD4, we demonstrated that the initial suppression of PDCD4 was mediated by miR-21 whilst sustained suppression was mediated by miR-499. Moreover the single miR-21 site was able to elicit the same magnitude of suppression as the three miR-499 sites. Conclusion: This study describes the regulation of PDCD4 specifically in tonsil SCC by miR-499 and miR-21 and has documented the loss of PDCD4 in tonsil SCCs. These findings highlight the complex interplay between miRNAs and tumour suppressor gene regulation and suggest that PDCD4 loss may be an important step in tonsillar carcinogenesis
What are the resourcing requirements for an Aboriginal and Torres Strait Islander primary healthcare research project?
Objective and importance
To explore the role of resourcing during an Aboriginal and Torres Strait Islander primary healthcare research project.
Study type
Process evaluation using grounded theory approaches of a national Aboriginal and Torres Strait Islander research project (N=500) named Getting it Right: The validation study.
Methods
Qualitative semi-structured interviews with thirty-six primary healthcare staff and four community members from nine of ten primary healthcare services (participating services) involved in the research project. Interviews included questions about the resources needed to conduct the research project, including flexible reimbursement to participating services (allocated within services), human resources and reimbursement to research participants (vouchers). Qualitative data were triangulated with participant feedback (questions about the aPHQ-9 [depression screening tool under examination] and free-text feedback collected during the research project), study administrative data (budgets, contracts, communication logs and ethics correspondence) and field notes kept by the interviewer.
Results
Three themes were identified: 1) the influence of reimbursement on participating services and the research project: 2) the influence of human resources on the research project at participating services; and 3) the consequences of offering vouchers to reimburse research participants. Reimbursement was allocated to research expenses (human resources and logistics) or non-research expenses (service operations, equipment and conference attendance costs). Most services opted to offer vouchers to compensate participants for their time, which staff considered was appropriate recognition of participants’ contributions and facilitated recruitment. Some staff described some potential unintended negative consequences from vouchers, including creating a welfare mentality or the wrong precedent.
Conclusion
Primary healthcare research should have sufficient resourcing available, including human resource capacity, to achieve research targets. Research planning should include consideration of the existing commitments, priorities and human capacity needs of services and patients
Smooth muscle cells affect differential nanoparticle accumulation in disturbed blood flow-induced murine atherosclerosis
Atherosclerosis is a lipid-driven chronic inflammatory disease that leads to the formation of plaques in the inner lining of arteries. Plaques form over a range of phenotypes, the most severe of which is vulnerable to rupture and causes most of the clinically significant events. In this study, we evaluated the efficacy of nanoparticles (NPs) to differentiate between two plaque phenotypes based on accumulation kinetics in a mouse model of atherosclerosis. This model uses a perivascular cuff to induce two regions of disturbed wall shear stress (WSS) on the inner lining of the instrumented artery, low (upstream) and multidirectional (downstream), which, in turn, cause the development of an unstable and stable plaque phenotype, respectively. To evaluate the influence of each WSS condition, in addition to the final plaque phenotype, in determining NP uptake, mice were injected with NPs at intermediate and fully developed stages of plaque growth. The kinetics of artery wall uptake were assessed in vivo using dynamic contrast-enhanced magnetic resonance imaging. At the intermediate stage, there was no difference in NP uptake between the two WSS conditions, although both were different from the control arteries. At the fully-developed stage, however, NP uptake was reduced in plaques induced by low WSS, but not multidirectional WSS. Histological evaluation of plaques induced by low WSS revealed a significant inverse correlation between the presence of smooth muscle cells and NP accumulation, particularly at the plaque-lumen interface, which did not exist with other constituents (lipid and collagen) and was not present in plaques induced by multidirectional WSS. These findings demonstrate that NP accumulation can be used to differentiate between unstable and stable murine atherosclerosis, but accumulation kinetics are not directly influenced by the WSS condition. This tool could be used as a diagnostic to evaluate the efficacy of experimental therapeutics for atherosclerosis
Supersymmetry and a Time-Dependent Landau System
A general technique is outlined for investigating supersymmetry properties of
a charged spin-\half quantum particle in time-varying electromagnetic fields.
The case of a time-varying uniform magnetic induction is examined and shown to
provide a physical realization of a supersymmetric quantum-mechanical system.
Group-theoretic methods are used to factorize the relevant Schr\"odinger
equations and obtain eigensolutions. The supercoherent states for this system
are constructed.Comment: 47 pages, submitted to Phys. Rev. A, LaTeX, IUHET 243 and
LA-UR-93-20
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