Energy Efficiency Improvements in Dry Drilling with Optimised Diamond-Like Carbon Coating

We demonstrate enhancements of performance and energy efficiency of cutting tools by deposition of diamond-like carbon (DLC) coatings on machine parts. DLC was deposited on steel drill bits, using plasma enhanced chemical vapour deposition (PECVD) with the acetylene precursor diluted with argon, to produce a surface with low friction and low wear rate. Drill bit performance in dry drilling of aluminium was quantified by analysis of power consumption and swarf flow. Optimised deposition conditions produced drill bits with greatly enhanced performance over uncoated drill bits, showing a 25% reduction in swarf clogging, a 36% reduction in power consumption and a greater than five-fold increase in lifetime. Surface analysis with scanning electron microscopy shows that DLC coated drills exhibit much lower aluminium build up on the trailing shank of the drill, enhancing the anti-adhering properties of the drill and reducing heat generation during operation, resulting in the observed improvements in efficiency. Variation of drilling efficiency with argon dilution of precursor is related to changes in the microstructure of the DLC coating

Small genome of Candidatus Blochmannia, the bacterial endosymbiont of Camponotus, implies irreversible specialization to an intracellular lifestyle

Author Posting. © Society for General Mircobiology, 2002. This article is posted here by permission of Society for General Mircobiology for personal use, not for redistribution. The definitive version was published in Microbiology 148 (2002): 2551-2556.Blochmannia (Candidatus Blochmannia gen. nov.) is the primary bacterial endosymbiont of the ant genus Camponotus. Like other obligate endosymbionts of insects, Blochmannia occurs exclusively within eukaryotic cells and has experienced long-term vertical transmission through host lineages. In this study, PFGE was used to estimate the genome size of Blochmannia as approximately 800 kb, which is significantly smaller than its free-living relatives in the enterobacteria. This small genome implies that Blochmannia has deleted most of the genetic machinery of related free-living bacteria. Due to restricted gene exchange in obligate endosymbionts, the substantial gene loss in Blochmannia and other insect mutualists may reflect irreversible specialization to a host cellular environment.This work was supported by grants to J. J.W. from the National Institutes of Health (R01 GM62626-01), the National Science Foundation (DEB 0089455) and the Josephine Bay Paul and C. Michael Paul Foundation

The effect of time-to-surgery on outcome in elderly patients with proximal femoral fractures

<p>Abstract</p> <p>Background</p> <p>Whether reducing time-to-surgery for elderly patients suffering from hip fracture results in better outcomes remains subject to controversial debates.</p> <p>Methods</p> <p>As part of a prospective observational study conducted between January 2002 and September 2003 on hip-fracture patients from 268 acute-care hospitals all over Germany, we investigated the relationship of time-to-surgery with frequency of post-operative complications and one-year mortality in elderly patients (age ≥65) with isolated proximal femoral fracture (femoral neck fracture or pertrochanteric femoral fracture). Patients with short (≤12 h), medium (> 12 h to ≤36 h) and long (> 36 h) times-to-surgery, counting from the time of the fracture event, were compared for patient characteristics, operative procedures, post-operative complications and one-year mortality.</p> <p>Results</p> <p>Hospital data were available for 2916 hip-fracture patients (mean age (SD) in years: 82.1 (7.4), median age: 82; 79.7% women). Comparison of groups with short (n = 802), medium (n = 1191) and long (n = 923) time-to-surgery revealed statistically significant differences in a few patient characteristics (age, American Society of Anesthesiologists ratings classification and type of admission) and in operative procedures (total hip endoprosthesis, hemi-endoprosthetic implants, other osteosynthetic procedures). However, comparison of these same groups for frequency of postoperative complications revealed only some non-significant associations with certain complications such as post-operative bleeding requiring treatment (early surgery patients) and urinary tract infections (delayed surgery patients). Both unadjusted rates of one-year all-cause mortality (between 18.1% and 20.5%), and the multivariate-adjusted hazard ratios (HR for time-to-surgery: 1.04; p = 0.55) showed no association between mortality and time-to-surgery.</p> <p>Conclusion</p> <p>Although this study found a trend toward more frequent post-operative complications in the longest time-to-surgery group, there was no effect of time-to-surgery on mortality. Shorter time-to-surgery may be associated with somewhat lower rates of post-operative complications such as decubitus ulcers, urinary tract infections, thromboses, pneumonia and cardiovascular events, and with somewhat higher rates of others such as post-operative bleeding or implant complications.</p

A new developmental mechanism for the separation of the mammalian middle ear ossicles from the jaw

Multiple mammalian lineages independently evolved a definitive mammalian middle ear (DMME) through breakdown of Meckel's cartilage (MC). However, the cellular and molecular drivers of this evolutionary transition remain unknown for most mammal groups. Here, we identify such drivers in the living marsupial opossum Monodelphis domestica, whose MC transformation during development anatomically mirrors the evolutionary transformation observed in fossils. Specifically, we link increases in cellular apoptosis and TGF-BR2 signalling to MC breakdown in opossums. We demonstrate that a simple change in TGF-β signalling is sufficient to inhibit MC breakdown during opossum development, indicating that changes in TGF-β signalling might be key during mammalian evolution. Furthermore, the apoptosis that we observe during opossum MC breakdown does not seemingly occur in mouse, consistent with homoplastic DMME evolution in the marsupial and placental lineages

Intention to have the seasonal influenza vaccination during the COVID-19 pandemic among eligible adults in the UK: a cross-sectional survey

OBJECTIVE: To investigate the likelihood of having the seasonal influenza vaccination during the COVID-19 pandemic in individuals who were eligible to receive it. DESIGN: We conducted a cross-sectional online survey in July 2020. We included predictors informed by previous research, in the following categories: sociodemographic variables; uptake of influenza vaccine last winter and beliefs about vaccination. PARTICIPANTS: 570 participants (mean age: 53.07; 56.3% female, 87.0% white) who were eligible for the free seasonal influenza vaccination in the UK. RESULTS: 59.7% of our sample indicated they were likely to have the seasonal influenza vaccination, 22.1% reported being unlikely to have the vaccination and 18.2% were unsure. We used logistic regression to investigate variables associated with intention to receive a seasonal influenza vaccine in the 2020-2021 season. A positive attitude to vaccination in general predicted intention to have the influenza vaccine in 2020-2021 (OR 1.45, 95% CI 1.19 to 1.77, p<0.001) but the strongest predictor of intention was previous influenza vaccination behaviour (OR 278.58, 95% CI 78.04 to 994.46, p<0.001). CONCLUSIONS: Previous research suggests that increasing uptake of the influenza vaccination may help contain a COVID-19 outbreak, so steps need to be taken to convert intention into behaviour and to reach those individuals who reported being unlikely or unsure about having the vaccine

Parents’ intention to vaccinate their child for COVID-19: a cross-sectional survey (CoVAccS – wave 3)

AbstractObjectivesTo investigate UK parents’ vaccination intention at a time when COVID-19 vaccination was available to some children.Study designData reported are from the second wave of a prospective cohort study.MethodsOnline survey of 270 UK parents (conducted 4-15 October 2021). At this time, vaccination was available to 16- and 17-year-olds and had become available to 12- to 15- year-olds two weeks prior. We asked participants whose child had not yet been vaccinated how likely they were to vaccinate their child for COVID-19. Linear regression analyses were used to investigate factors associated with intention. Parents were also asked for their main reasons behind vaccination intention. Open-ended responses were analysed using content analysis.ResultsParental vaccination intention was mixed (likely: 39.3%, 95% CI 32.8%, 45.7%; uncertain: 33.9%, 27.7%, 40.2%; unlikely: 26.8%, 20.9%, 32.6%). Intention was associated with: parental COVID-19 vaccination status; greater perceived necessity and social norms regarding COVID-19 vaccination; greater COVID-19 threat appraisal; and lower vaccine safety and novelty concerns. In those who intended to vaccinate their child, the main reasons for doing so were to protect the child and others. In those who did not intend to vaccinate their child, the main reason was safety concerns.ConclusionsParent COVID-19 vaccination and psychological factors explained a large percentage of the variance in vaccination intention for one’s child. How fluctuating infection rates, more children being vaccinated, and the UK’s reliance on vaccination as a strategy to live with COVID-19 may impact parents’ intention to vaccinate their child requires further study.</jats:sec

Molecular typing of Rickettsia akari

Rickettsia akari, an obligately intracellular bacterium, is the causative agent of the cosmopolitan urban disease rickettsialpox. R. akari is an atypical representative of spotted fever group rickettsiae (SFG) as it is associated with rodent mites rather than ticks or fleas; however, only limited information is available about the degree of genetic variability found among isolates of R. akari. We examined 13 isolates of R. akari from humans, rodents and mites in the USA, the former Soviet Union, and the former Yugoslavia made between 1946 and 2003 for diversity in their tandem repeat regions (TR) and intergenic regions (IGR). The 1.23 Mb genome of R. akari strain Hartford CWPP was analyzed using Tandem Repeat Finder software (http://tandem.bu.edu) and 374 different TRs were identified, with size variation from 1 to 483 bp and with TR copy numbers ranging between 21 and 1.9, respectively. No size polymorphisms were detected among the 11 TR regions examined from 5 open reading frames and 6 IGR. Eighteen non-TR IGR’s were amplified and sequenced for the same isolates comprising a total of 5.995 bp (0.49%) of the Hartford CWPP strain chromosome. Three single nucleotide polymorphism (SNP) sites were detected in two IGR’s which permitted separation of the five R. akari isolates from Ukraine SSR from the other eight isolates. In conclusion, this is the first study reporting genetic heterogeneity among R. akari isolates of different geographic origins. Further exploration of this genetic diversity is needed to understand better the geographic distribution of R. akari and the epidemiology of rickettsialpox. The potential of mites as hosts for other rickettsial agents also needs further investigation