Surface excitonic emission and quenching effects in ZnO nanowire/nanowall systems: limiting effects on device potential.

We report ZnO nanowire/nanowall growth using a two-step vapour phase transport method on a-plane sapphire. X-ray diffraction and scanning electron microscopy data establish that the nanostructures are vertically well-aligned with c-axis normal to the substrate, and have a very low rocking curve width. Photoluminescence data at low temperatures demonstrate the exceptionally high optical quality of these structures, with intense emission and narrow bound exciton linewidths. We observe a high energy excitonic emission at low temperatures close to the band-edge which we assign to the surface exciton in ZnO at ~ 3.366 eV, the first time this feature has been reported in ZnO nanorod systems. This assignment is consistent with the large surface to volume ratio of the nanowire systems and indicates that this large ratio has a significant effect on the luminescence even at low temperatures. The band-edge intensity decays rapidly with increasing temperature compared to bulk single crystal material, indicating a strong temperature-activated non-radiative mechanism peculiar to the nanostructures. No evidence is seen of the free exciton emission due to exciton delocalisation in the nanostructures with increased temperature, unlike the behaviour in bulk material. The use of such nanostructures in room temperature optoelectronic devices appears to be dependent on the control or elimination of such surface effects

Microwave Tomographic Imaging Utilizing Low-Profile, Rotating, Right Angle-Bent Monopole Antennas

We have developed a simple mechanism incorporating feedline bends and rotary joints to enable motion of a monopole antenna within a liquid-based illumination chamber for tomographic imaging. The monopole is particularly well suited for this scenario because of its small size and simplicity. For the application presented here a full set of measurement data is collected from most illumination and receive directions utilizing only a pair of antennas configured with the rotating fixture underneath the imaging tank. Alternatively, the concept can be adapted for feed structures entering the tank from the sides to allow for measurements with vertically and horizontally polarized antennas. This opens the door for more advanced imaging applications where anisotropy could play an important role such as in bone imaging

Farm management factors associated with bulk tank total bacterial count in Irish dairy herds during 2006/07

Research has shown that total bacterial count (TBC), which is the bacterial growth per ml of milk over a fixed period of time, can be decreased by good hygiene and farm management practices. The objective of the current study was to quantify the associations between herd management factors and bulk tank TBC in Irish spring calving, grass-based dairy herds. The relationship between bulk tank TBC and farm management and infrastructure was examined using data from 400 randomly selected Irish dairy farms where the basal diet was grazed grass. Herd management factors associated with bulk tank TBC were identified using linear models with herd annual total bacterial score (i.e., arithmetic mean of the natural logarithm of bulk tank TBC) included as the dependent variable. All herd management factors were individually analysed in a separate regression model, that included an adjustment for geographical location of the farm. A multiple stepwise regression model was subsequently developed. Median bulk tank TBC for the sample herds was 18,483 cells/ml ranging from 10,441 to 130,458 cells/ml. Results from the multivariate analysis indicated that the following management practices were associated with low TBC; use of heated water in the milking parlour; participation in a milk recording scheme; and tail clipping of cows at a frequency greater than once per year. Increased level of hygiene of the parlour and cubicles were also associated with lower TBC. Herd management factors associated with bulk tank TBC in Irish grazing herds were generally in agreement with most previous studies from confinement systems of milk production

Acute recovery from exercise in people with multiple sclerosis: an exploratory study on the effect of exercise intensity

Purpose A better understanding of how people with Multiple Sclerosis (pwMS) recover from exercise may help inform interventions. Methods We explored physiological and perceptual responses following exercise of different intensities, using a crossover exposure-response design, in 14 adults with MS and nine controls. A cycling exercise test determined maximum capacity (Wpeak). Participants then performed 20minute exercise sessions relative to Wpeak (random order separated by 7days): 1) 45% and 2) 60% continuous cycling, and 3) 90% intermittent cycling (30seconds cycling, 30seconds rest). During a 45minute recovery period, tympanic temperature (Temp°C), exertion in breathing (RPEbr) and legs (RPEleg), and cortical excitability (MEParea) were measured. Results Eleven pwMS and eight controls completed the study. Controls performed better on the exercise test (p<0.05), thus more absolute work during subsequent sessions. PwMS took longer to recover RPEleg with recovery time increasing with intensity (45%-6mins; 60%-15mins; 90%-35mins) and correlating with Temp°C. MEParea was significantly depressed in both groups at 45% and 60% (p<0.001), in the MS group; this also correlated with RPEleg. Conclusion Feelings of leg exertion may persist after exercise in some pwMS, especially at high intensities. This may relate to body temperature and, after continuous exercise, cortical excitability. These results support considering the recovery period post exercise and provide insight into potential correlates of post exercise fatigu

Microwave Tomographic Imaging Utilizing Low-Profile, Rotating, Right Angle-Bent Monopole Antennas

We have developed a simple mechanism incorporating feedline bends and rotary joints to enable motion of a monopole antenna within a liquid-based illumination chamber for tomographic imaging. The monopole is particularly well suited for this scenario because of its small size and simplicity. For the application presented here a full set of measurement data is collected from most illumination and receive directions utilizing only a pair of antennas configured with the rotating fixture underneath the imaging tank. Alternatively, the concept can be adapted for feed structures entering the tank from the sides to allow for measurements with vertically and horizontally polarized antennas. This opens the door for more advanced imaging applications where anisotropy could play an important role such as in bone imaging

The impact of COVID-19 on pregnant womens’ experiences and perceptions of antenatal maternity care, social support, and stress-reduction strategies

Background: The COVID-19 pandemic has impacted on maternity care, supports and women's mental health. Aim: The aim of this study was to assess pregnant women's satisfaction with antenatal care and social support and to examine stress-reduction strategies women used during the pandemic. Methods: An online survey was conducted between June and July 2020. Pregnant women, aged over 18 years were recruited. The survey included closed and open-ended questions to assess women's perceptions and satisfaction with their antenatal care, social support, and stress-reduction strategies. Descriptive statistics and multivariate analysis were used for quantitative analyses; qualitative content analysis was used for open-ended questions. Findings: 573 pregnant women completed the survey. Women reported low levels of social support which was predicted by women's mental health and demographic factors and was related to public health and maternity service restrictions. Women reported that restrictions implemented in the maternity services limited their face-to face interactions with healthcare professionals and meant their partners could not attend antenatal appointments or support them in the postpartum period in the maternity setting. The lack of information on COVID-19 and pregnancy meant women had greater uncertainty about pregnancy and birth. Discussion: Our findings indicate how the lack of access to antenatal care and reduced perceived social support as a result of the restrictions implemented in response to the COVID-19 pandemic, potentially intensifies pregnancy specific stress. Conclusions: There is a need for the provision of supportive care, both formally and informally, particularly with women who may be more vulnerable during a pandemic

Family Medicine needs assessment: Studying the clinical work of general practitioners in Ethiopia

Background and Objective: Some universities in sub-Saharan Africa have initiated Family Medicine (FM) residency programs. This study was conducted by FM colleagues at Addis Ababa University (AAU) in Ethiopia and the University of Toronto, Canada to inform the FM residency curriculum at AAU. It was designed to determine the clinical problems that family physicians in Ethiopia may encounter.Methods: We used a mixed methods approach: Modified time-motion study and brief interviews. We observed 46 general practitioners (GPs) across ten sites in Ethiopia. Trained observers recorded time-motion data while GPs conducted their daily work. This data was supplemented by brief interviews with the GPs.Findings: Clinical encounters occupied 82% of GP work. The common symptoms were digestive-abdominal pain (21% visits), respiratory-cough (16%), and general-fever and chills (16%). The common diagnoses were infectious (22% visits), genitourinary (12%), circulatory (10%), and endocrine (10%). Challenges identified were lack of clinical resources (57% of GPs), difficulties in communication (48%) and excessive workload (33%). Most common requests were for information technology (78%) and HIV (46%) training.Conclusion: The profile of common symptoms and diagnoses indicated the competencies family physicians in the regions should have. This information will be used to develop an appropriate FM curriculum at AAU

Prenatal stress, health, and health behaviours during the COVID-19 pandemic: An international survey.

BACKGROUND: Pregnant women's stress, mental and physical health, and health behaviours can have important implications for maternal and child health outcomes. AIM: To examine pregnant women's levels of stress, mental and physical health, and health behaviours during the COVID-19 pandemic. METHODS: A cross-sectional survey was conducted online, with recruitment and data collection occurring between 16/6/20 and 17/7/20. Participants were pregnant women recruited via online pregnancy/parenting communities. Participants self-reported their levels of general stress, pregnancy-specific stress and COVID-19 related stress, mental and physical health, general health behaviours, and COVID-19 related health behaviours. FINDINGS: 573 pregnant women participated in the survey. Participants were most commonly resident in the United States (42.6%, n=243), Ireland (41.2%, n=235) or the United Kingdom (10%, n=57). The majority (80.0%, n=457) were married and educated to degree level or above (79.3, n=453). Pregnant women reported high levels of pregnancy-specific and COVID-19-related stress, and low levels of mental and physical health, during the pandemic. Encouragingly, pregnant women in this study generally reported high levels of adherence to public health advice and pregnancy health behaviours. Stress and general mental health outcomes were best predicted by well-being factors (including stress and social support). Health impairing behaviours (e.g. poor diet) were predicted by both well-being and demographic factors. DISCUSSION: Interventions targeting pregnancy- and pandemic-specific stress at the population level will be essential to support mental health and minimise adverse outcomes for women and children during the pandemic