An evaluation of the use of individual grass species in retaining polluted soil and dust particulates in vegetated sustainable drainage devices

A sustainable means of preventing polluted particulates carried in urban storm water entering rivers, groundwater and lakes is by employing vegetated sustainable drainage system (SUDS) devices, or best management practices to trap or biodegrade them. In the UK, a mixture of grass species is recommended for use in devices such as swales or filter strips. However, there is little evidence in support of the efficiency of the individual grasses or mixtures to deal with such contaminated material. A pot-based pollutant retention study was conducted using processed street dust from central Coventry, UK, as a simulated pollutant to be applied in different quantities to a variety of recommended grasses for vegetated SUDS devices. Analysis was conducted on compost cores, roots and shoots for heavy metals (Cd, Cu, Ni, Pb and Zn). Street dust mainly concentrated in the top compost layer for all grasses with only the finer material migrating down the profile. Analysis of roots indicated little accumulation, with ANOVA statistical tests indicating significant differences in heavy metal concentrations, with less in the compost and more in the shoots. Development of root systems on or near the surface possibly explains increased uptake of heavy metals by some species. Overall Agrostis canina and Poa pratensis showed the greatest accumulations compared to their controls although Agrostis capillaris syn.tenuis and Agrostis stolonifera also demonstrated accumulation potential. On ranking, Agrostis canina and Poa pratensis were highest overall. These rankings will assist in selecting the best grasses to address pollution of the urban environment by contaminated particulates.

Progress testing in undergraduate dental education: the Peninsula experience and future opportunities

BACKGROUND

Progress testing is well established as a longitudinal form of assessment in undergraduate medical programmes to measure growth in knowledge. Peninsula Dental School is the first school to use progress testing and remains the only one to do so.

AIMS

To share the experience of developing progress testing in an undergraduate dental programme as a major summative assessment tool at a newly established dental school in the United Kingdom.

METHODS

Data were collected for progress tests conducted from 2007 to 14. The tests were formative in the first 2 years of the programme and summative in subsequent years. Each test was based on 100 single best answer multiple-choice items with an appropriate vignette. The students chose their answer from 5 options. A score 1 mark is awarded for each correct answer, minus 0.25 for an incorrect answer and 0 for 'don't know' (DK). The standard setting for each sitting was carried out using Angoff and Hofstee methods.

RESULTS

There were two tests per year with each cohort undertaking eight tests in their 4 years of study providing a total 14 test occasions. The reliability of each test for each student cohort tests was measured using Cronbach's alpha. The average reliability over 42 test/cohort combinations was 0.753 (±SD 0.08). Data analyses show growth in knowledge of dental students across successive years with the largest increase in knowledge observed between tests 1 and 5 and concomitant reduction in DK responses.

CONCLUSION

This is the first study to report the establishment and use of progress testing as the principle form of written summative testing in an undergraduate dental curriculum. Progress testing is a valid and reliable tool to assess growth in knowledge longitudinally over the duration of a dental programme. Although a labour-intensive process, progress testing merits more widespread use in dental programmes.

Widespread detection of highly pathogenic H5 influenza viruses in wild birds from the Pacific Flyway of the United States

A novel highly pathogenic avian influenza virus belonging to the H5 clade 2.3.4.4 variant viruses was detected in North America in late 2014. Motivated by the identification of these viruses in domestic poultry in Canada, an intensive study was initiated to conduct highly pathogenic avian influenza surveillance in wild birds in the Pacific Flyway of the United States. A total of 4,729 hunter-harvested wild birds were sampled and highly pathogenic avian influenza virus was detected in 1.3% (n = 63). Three H5 clade 2.3.4.4 subtypes were isolated from wild birds, H5N2, H5N8, and H5N1, representing the wholly Eurasian lineage H5N8 and two novel reassortant viruses. Testing of 150 additional wild birds during avian morbidity and mortality investigations in Washington yielded 10 (6.7%) additional highly pathogenic avian influenza isolates (H5N8 = 3 and H5N2 = 7). The geographically widespread detection of these viruses in apparently healthy wild waterfowl suggest that the H5 clade 2.3.4.4 variant viruses may behave similarly in this taxonomic group whereby many waterfowl species are susceptible to infection but do not demonstrate obvious clinical disease. Despite these findings in wild waterfowl, mortality has been documented for some wild bird species and losses in US domestic poultry during the first half of 2015 were unprecedented.

Association of Anaesthetists of Great Britain and Ireland: Safe vascular access 2016

Safe vascular access is integral to anaesthetic and critical care practice, but procedures are a frequent source of patient adverse events. Ensuring safe and effective approaches to vascular catheter insertion should be a priority for all practitioners. New technology such as ultrasound and other imaging has increased the number of tools available. This guidance was created using review of current practice and literature, as well as expert opinion. The result is a consensus document which provides practical advice on the safe insertion and removal of vascular access devices.

Prevalence of pelvic floor symptoms in female patients attending the two-week wait clinic with suspected colorectal cancer

Introduction The aim of this study was to establish the prevalence of pelvic floor symptoms in women referred to a colorectal two-week wait (2WW) clinic with suspected colorectal cancer. Methods A questionnaire assessing faecal incontinence (FI) (Wexner score) and obstructed defecation syndrome (ODS) (Renzi score) was offered to 98 consecutive female patients attending a colorectal 2WW clinic at a single trust. Results Overall, 56 (57%) of the 98 patients had significant ODS and/or FI (scores >9/20), 33 (34%) had ODS and 40 (41%) had FI. Seventeen patients (17%) had both ODS and FI. Analysis of the 63 patients referred with a change in bowel habit (CIBH) showed 40 (63%) to be Renzi and/or Wexner positive compared with 16 (46%) of the 35 patients who presented without CIBH (p=0.095, Fisher's exact test). Further analysis showed that 31 (78%) of the 40 patients with FI presented with CIBH compared with 32 (55%) of the 58 without FI (p=0.032). In terms of ODS, 23 (70%) of the 33 patients with ODS presented with CIBH compared with 40 (62%) of the 65 without ODS (p=0.506). Conclusions Over half of the female patients attending our colorectal 2WW clinic had significant pelvic floor dysfunction (FI/ODS), which may account for their symptoms (especially in the CIBH referral category). While it is important for malignancy to be excluded, many patients may benefit from investigation and management of their pelvic floor dysfunction as the cause for their presenting symptoms.

Does the site of anastomosis for esophagectomy affect long-term quality of life?

Long-term survival after esophagectomy is improving, and hence, quality of life (QOL) of these patients has become a priority. There has been extensive debate regarding the optimal site of surgical anastomosis (cervical or intrathoracic). We aimed to evaluate the impact of anastomotic site on long-term QOL postesophagectomy. Quality of life questionnaires (European Organisation for Research and Treatment of Cancer [EORTC] C-30 and OG-25) were sent to patients surviving over 3 years following esophagectomy. The data were analyzed by site of esophagogastric anastomosis: intrathoracic or cervical. EORTC C-30 data were compared against the reference population data. Of the patients, 62 responded (82%) with a median time postsurgery of 6.1 years (range 3-12 years). Patient demographics were comparable. There was no significant difference between cervical or intrathoracic anastomosis groups for functional or symptom scores, focusing on dysphagia (cervical = 8.8 vs. intrathoracic = 17.6, P = 0.24), odynophagia (cervical = 13.4 vs. intrathoracic = 16.1, P = 0.68) and swallowing problems (cervical = 8.1 vs. intrathoracic = 13.4, P = 0.32). There was no difference in overall health score between groups (cervical = 70.5 vs. intrathoracic = 71.6, P = 0.46). Overall general health score was comparable with the reference population (esophagectomy group P = 70.9 ± 22.1 vs. reference population = 71.2 ± 22.4, P = 0.93). There is no difference in long-term QOL after esophagectomy between patients with a cervical or intrathoracic anastomosis. Scores compare favorably with EORTC reference data. Survival after esophagectomy is associated with recovery of QOL in the long term, regardless of site of anastomosis and despite worse gastrointestinal-related symptoms.

Attitudes towards mental illness of nursing students in a Baccalaureate programme in Jamaica: a questionnaire survey

There is longstanding evidence of nurses demonstrating negative attitudes towards people with mental illness. Student nurses' fear or discomfort with mentally ill patients results in poorer outcomes for patients and students' dissatisfaction with their experience of mental health nursing. There is evidence of negative attitudes towards mental illness in the Jamaican society; however, no studies have explored whether these attitudes are held by nursing students. The aim of the study was to examine the attitudes of nursing students towards mental illness. A questionnaire survey was conducted with a convenience sample of 143 third-year nursing students who were enrolled in a baccalaureate programme. Data were collected using the Attitudes Towards Acute Mental Health Scale (ATAMHS). A response rate of 71% was achieved for the survey. The findings indicated that the student nurses held an overall negative attitude towards mental illness, with a general perception that mentally ill people are dangerous. The student nurses were divided in their opinions in a number of areas, suggesting a possible conflict of opinions. Negative attitudes towards mental illness impact client outcomes and the career choices made by nurses. This study provides baseline data within the Jamaican context that adds to the evidence on nursing students' attitude to mental illness. Further research is needed to explore whether nursing education and clinical experience enables student nurses in Jamaica to develop a more positive attitude towards mental illness and mental health nursing and whether cultural factors contribute to negative attitudes.

Ileostomy obstruction by ingested apricot stone with clinical-radiological-pathological correlation

Patients with stomas often present with bowel obstruction, often secondary to adhesions. This case describes the presentation, investigation and management of a 62-year-old woman with an end ileostomy, who presented to hospital with acute abdominal pain and subacute bowel obstruction. Further questioning revealed the recent ingestion of an apricot stone and this was identified by multimodality imaging as the cause of the luminal obstruction in the distal ileum, just proximal to the stoma. After a failed period of conservative management, examination under anaesthesia was performed and digital extraction attempted, but this was unsuccessful. Rather than surgical stoma revision, endoscopic removal was achieved. The patient improved and was discharged the following day. However, her small bowel obstruction relapsed within 48 h. She was readmitted and underwent stoma revision with no further problems.

Choice of tip, signal stability, and practical aspects of piezoresponse-force-microscopy

Piezoresponse force-microscopy (PFM) has become the standard tool to investigate ferroelectrics on the micro- and nanoscale. However, reliability of PFM signals is often problematic and their quantification is challenging and thus not widely applied. Here, we present a study of the reproducibility of PFM signals and of the so-called PFM background signal which has been reported in the literature. We find that PFM signals are generally reproducible to certain extents. The PFM signal difference between 180° domains on periodically poled lithium niobate (PPLN) is taken as the reference signal in a large number of measurements, carried out in a low frequency regime (30-70 kHz). We show that in comparison to Pt coated tips, diamond coated tips exhibit improved signal stability, lower background signal, and less imaging artifacts related to PFM which is reflected in the spread of measurements. This is attributed to the improved mechanical stability of the conductive layer. The average deviation of the mean PFM signal is 38.3%, for a diamond coated tip. Although this deviation is relatively high, it is far better than values from the literature which showed a deviation of approx. 73.1%. Additionally, we find that the average deviation of the background signal from 0 is 11.6% of the PPLN domain contrast. Thus, the background signal needs to be taken into account when quantifying PFM signals and should be subtracted from PFM signals. Those results are important for quantification of PFM signals, since PPLN might be used for this purpose when PFM signals measured on PPLN are related to its macroscopic d33 coefficient. Finally, the crucial influence of sample polishing on PFM signals is shown and we recommend to use a multistep polishing route with a final step involving 200 nm sized colloidal silica particles.

Antimicrobial susceptibilities and random amplified polymorphic DNA-PCR fingerprint characterization of Lactococcus lactis ssp. lactis and Lactococcus garvieae isolated from bovine intramammary infections

In total, 181 streptococci-like bacteria isolated from intramammary infections (IMI) were submitted by a veterinary clinic to Quality Milk Production Services (QMPS, Cornell University, Ithaca, NY). The isolates were characterized by sequence analysis, and 46 Lactococcus lactis ssp. lactis and 47 Lactococcus garvieae were tested for susceptibility to 17 antibiotics. No resistant strains were found for β-lactam antibiotics widely used in clinical practice (penicillin, ampicillin, and amoxicillin), and all minimum inhibitory concentrations (MIC) were far from the resistance breakpoints. Eight strains had MIC intermediate to cefazolin. The random amplification of polymorphic DNA (RAPD)-PCR fingerprint patterns showed a slightly higher heterogeneity for Lc. lactis ssp. lactis isolates than for Lc. garvieae isolates.

Thioredoxin rod-derived cone viability factor protects against photooxidative retinal damage

Rod-derived cone viability factor (RdCVF) is a trophic factor of the thioredoxins family that promotes the survival of cone photoreceptors. It is encoded by the nucleoredoxin-like gene 1 Nxnl1 which also encodes by alternative splicing a long form of RdCVF (RdCVFL), a thioredoxin enzyme that interacts with TAU. The known role of thioredoxins in the defense mechanism against oxidative damage led us to examine the retinal phenotype of the Nxnl1(-/-) mice exposed to photooxidative stress. Here we found that, in contrast to wild-type mice, the rod photoreceptors of Nxnl1(-/-) mice are more sensitive to light after exposure to 1700 or 2500 lx. The delivery of RdCVF by AAV to mice deficient of Nxnl1(-/-) protects rod photoreceptors from light damage. Interestingly, the RdCVF2L protein, encoded by the paralog gene Nxnl2, is able to reduce TAU phosphorylation, as does RdCVFL, but does not protect the rod from light damage. Our result shows that the Nxnl1 gene, through the thioredoxin RdCVFL, is part of an endogenous defense mechanism against photooxidative stress that is likely of great importance for human vision.

Crystallographic Aspects of the CDW Instabilities in NbSe3

Charge-density waves (CDW) in some quasi one-dimensional compounds can be depinned from the lattice by an external electric field. In the case of NbSe3, two CDW transitions have been reported with onset temperatures of 144 K and 59 K. From an analysis of the published low-temperature (LT) scanning tunneling microscopy (STM) images, which inherently allow the resolution of domain structures on the atomic scale, an alternative model of the CDW modulated structures in NbSe3 is proposed. In contrast to the existing model, where two incommensurate (IC) modes, q1 = (0,0.241,0) and q2 = (0.5,0.260,0.5) are selectively confined to two of three available structurally distinguished types of bi-capped trigonal prismatic columns, the alternative model [1,2] proceeds from the assumption that both columns of the same pair are alternatively modulated by the two modes, whose IC components add within experimental error into a commensurate value. The observed domains are formed as a result of the different bonding within and between the structural layers, separated by Van der Waals gaps, and of the ability of the two modes to be easily interchanged between two symmetry-related columns of the same type. This assumption is in accord with the published LT STM results, which confirm i.a. the presence of both IC modes above 59 K, where according to the previous model only the q1 contribution should be expected. A pair of two alternatively modulated columns of the same type represents the basic structural unit of the CDW ground state. The two modes can formally be replaced by a single inharmonic modulation, obtained by "beating" between the two IC modes.