Comparison of two methods of fatigue testing bone cement

Two different methods have been used to fatigue test four bone cements. Each method has been used previously, but the results have not been compared. The ISO 527-based method tests a minimum of 10 samples over a single stress range in tension only and uses Weibull analysis to calculate the median number of cycles to failure and the Weibull modulus. The ASTM F2118 test regime uses fewer specimens at various stress levels tested in fully reversed tension–compression, and generates a stress vs. number of cycles to failure (S–N) or Wöhler curve. Data from specimens with pores greater than 1 mm across is rejected. The ISO 527-based test while quicker to perform, provides only tensile fatigue data, but the material tested includes pores, thus the cement is closer to cement in clinical application. The ASTM regime uses tension and compression loading and multiple stress levels, thus is closer to physiological loading, but excludes specimens with defects obviously greater than 1 mm, so is less representative of cement in vivo. The fatigue lives between the cements were up to a factor 15 different for the single stress level tension only tests, while they were only a factor of 2 different in the fully reversed tension–compression testing. The ISO 527-based results are more sensitive to surface flaws, thus the differences found using ASTM F2118 are more indicative of differences in the fatigue lives. However, ISO 527-based tests are quicker, so are useful for initial screening

The prevalence and frequency of menstrual cycle symptoms are associated with women’s availability to train and compete: A study of 6,812 exercising women recruited using the STRAVA™ exercise app

Objectives: The menstrual cycle can affect sports participation and exercise performance. There are very few data on the specific menstrual cycle symptoms (symptoms during various phases of the cycle, not only during menstruation) experienced by exercising women. We aimed to characterise the most common symptoms; the number and frequency of symptoms; and we evaluated whether menstrual cycle symptoms were associated with sporting outcomes. Methods: 6,812 adult women of reproductive age (mean age: 38.3 (8.7) years) who were not using combined hormonal contraception were recruited via the STRAVA exercise app user database and completed a 39-part survey. Respondents were from seven geographical areas, and questions were translated and localised to each region (Brazil, n=1,288; France, n=1,911; Germany, n=1,178; Spain, n=1,204; UK & Ireland, n=2,311; and USA, n=2,479). The survey captured exercise behaviours; current menstrual status; the presence and frequency of menstrual cycle symptoms; medication use for symptoms; perceived effects of the menstrual cycle on exercise and work behaviours; and history of hormonal contraception use. We propose a novel Menstrual Symptom index (MSi) based on the presence and frequency of 18 commonly reported symptoms (range 0-54 where 54 would be all 18 symptoms each occurring very frequently). Results: The most prevalent menstrual cycle symptoms were mood changes/anxiety (90.6%), tiredness/fatigue (86.2%), stomach cramps (84.2%), and breast pain/tenderness (83.1%). After controlling for BMI, training volume and age, the Menstrual Symptom Index was associated with a greater likelihood of missing or changing training (OR= 1.09 (CI: 1.08,1.10); p<0.05), missing a sporting event/competition (OR= 1.07 (CI: 1.06,1.08); p=<0.05), absenteeism from work/academia (OR= 1.08 (CI: 1.07,1.09); p=<0.05), and use of pain medication (OR= 1.09 (CI: 1.08,1.09); p=<0.05). Conclusion: Menstrual cycle symptoms are very common in exercising women and women report that these symptoms compromise their exercise participation and work capacity. The Menstrual Symptom Index needs to be formally validated (psychometrics); at present it provides an easy way to quantify the frequency of menstrual cycle symptoms

Anteroposterior patterning of the zebrafish ear through Fgf- and Hh-dependent regulation of hmx3a expression

In the zebrafish, Fgf and Hh signalling assign anterior and posterior identity, respectively, to the poles of the developing ear. Mis-expression of fgf3 or inhibition of Hh signalling results in double-anterior ears, including ectopic expression of hmx3a. To understand how this double-anterior pattern is established, we characterised transcriptional responses in Fgf gain-of-signalling or Hh loss-of-signalling backgrounds. Mis-expression of fgf3 resulted in rapid expansion of anterior otic markers, refining over time to give the duplicated pattern. Response to Hh inhibition was very different: initial anteroposterior asymmetry was retained, with de novo duplicate expression domains appearing later. We show that Hmx3a is required for normal anterior otic patterning, and that otic patterning defects in hmx3a-/- mutants are a close phenocopy to those seen in fgf3-/- mutants. However, neither loss nor gain of hmx3a function was sufficient to generate full ear duplications. Using our data to infer a transcriptional regulatory network required for acquisition of otic anterior identity, we can recapitulate both the wild-type and the double-anterior pattern in a mathematical model

Rare genetic variation in UNC13A may modify survival in amyotrophic lateral sclerosis

Our objective was to identify whether rare genetic variation in amyotrophic lateral sclerosis (ALS) candidate survival genes modifies ALS survival. Candidate genes were selected based on evidence for modifying ALS survival. Each tail of the extreme 1.5% of survival was selected from the UK MND DNA Bank and all samples available underwent whole genome sequencing. A replication set from the Netherlands was used for validation. Sequences of candidate survival genes were extracted and variants passing quality control with a minor allele frequency ≤0.05 were selected for association testing. Analysis was by burden testing using SKAT. Candidate survival genes UNC13A, KIFAP3, and EPHA4 were tested for association in a UK sample comprising 25 short survivors and 25 long survivors. Results showed that only SNVs in UNC13A were associated with survival (p = 6.57 × 10−3). SNV rs10419420:G > A was found exclusively in long survivors (3/25) and rs4808092:G > A exclusively in short survivors (4/25). These findings were not replicated in a Dutch sample. In conclusion, population specific rare variants of UNC13A may modulate survival in ALS

Identification of new states in 26Si using the29Si(3He,6He)26Si reaction and consequences for the 25Al(p,y)26Si reaction rate in explosive hydrogen burning environments

We have studied the [Formula Presented] reaction and have identified new states in [Formula Presented] at [Formula Presented] and [Formula Presented] Based on these measurements and other recent evidence, we suggest spin-parity assignments of [Formula Presented] for the 5.678 MeV state and [Formula Presented] for the 5.945 MeV state, which would account for all the “missing” unnatural parity states in [Formula Presented] in the excitation energy region important to hydrogen burning in novae. New reaction rates are presented for the [Formula Presented] reaction based on this possible assignment of states

COVID-19 - Considerations for the Female Athlete

The SARS CoV-2 virus (COVID-19) caused the whole sporting calendar to be paused. As we embark on the challenge of navigating through the return to play (RTP) process, there is a necessity to consider the needs of all athletes. This commentary specifically considers recommendations and requirements for the female athlete with a physiological emphasis during and following the COVID-19 pandemic, however, it will be relevant for any similar future scenarios that may present. It is important to acknowledge that there remain many unknowns surrounding COVID-19 and the female athlete both in the short- and long-term

A qualitative study of behavioral and social drivers of COVID-19 vaccine confidence and uptake among unvaccinated Americans in the US April-May 2021

Introduction Around one-third of Americans reported they were unwilling to get a COVID-19 vaccine in April 2021. This focus group study aimed to provide insights on the factors contributing to unvaccinated adults’ hesitancy or refusal to get vaccinated with COVID-19 vaccines. Method Ipsos recruited 59 unvaccinated US adults who were vaccine hesitant (i.e., conflicted about or opposed to receiving a COVID-19 vaccination) using the Ipsos KnowledgePanel. Trained facilitators led a total of 10 focus groups via video-conference in March and April 2021. Two coders manually coded the data from each group using a coding frame based on the focus group discussion guide. The coding team collaborated in analyzing the data for key themes. Results Data analysis of transcripts from the focus groups illuminated four main themes associated with COVID-19 vaccine hesitancy: lack of trust in experts and institutions; concern about the safety of COVID-19 vaccines; resistance towards prescriptive guidance and restrictions; and, despite personal reluctance or unwillingness to get vaccinated, acceptance of others getting vaccinated. Discussion Vaccine confidence communication strategies should address individual concerns, describe the benefits of COVID-19 vaccination, and highlight evolving science using factural and neutral presentations of information to foster trust

Functional diversity of chemokines and chemokine receptors in response to viral infection of the central nervous system.

Encounters with neurotropic viruses result in varied outcomes ranging from encephalitis, paralytic poliomyelitis or other serious consequences to relatively benign infection. One of the principal factors that control the outcome of infection is the localized tissue response and subsequent immune response directed against the invading toxic agent. It is the role of the immune system to contain and control the spread of virus infection in the central nervous system (CNS), and paradoxically, this response may also be pathologic. Chemokines are potent proinflammatory molecules whose expression within virally infected tissues is often associated with protection and/or pathology which correlates with migration and accumulation of immune cells. Indeed, studies with a neurotropic murine coronavirus, mouse hepatitis virus (MHV), have provided important insight into the functional roles of chemokines and chemokine receptors in participating in various aspects of host defense as well as disease development within the CNS. This chapter will highlight recent discoveries that have provided insight into the diverse biologic roles of chemokines and their receptors in coordinating immune responses following viral infection of the CNS

Cutting cardiovascular risk in barbershops

http://dx.doi.org/10.1016/j.jomh.2009.07.00