Tracing sources and fate of zinc in a mining-impacted river catchment: insights from flow measurements, synoptic sampling, and zinc isotopes

This paper reports on the comprehensive monitoring of the Rookhope Burn catchment in the Weardale valley, northern Pennines (Uk), which has been subject to lead, zinc, and fluorspar mining for over two centuries. Zinc is the major contaminant in surface waters, exceeding the Environmental Quality standard value for salmonid fish. synoptic flow monitoring and water sampling have been carried out, including both inflow and instream sampling points along the Rookhope Burn, with the purpose of tracing both point and diffuse sources of Zn throughout the catchment. The Zn load profile suggests an important role for Zn-rich groundwater contributions to the stream bed and has also established the existence of Zn sinks. Evidence from hyporheic zone sampling suggests Zn reaction or surface complexation with Mn oxide surfaces forming on stream bed sediments as a potential mechanism responsible for the observed metal attenuation. Current work is focused on testing the potential of Zn isotopes to fingerprint sources and pathways of Zn in the aquatic system. Preliminary results show significant variation in the stream water Zn isotopic signature from the headwaters to the base of the catchment

Becoming active in the micro-politics of healthcare re-organisation:The identity work and political activation of doctors, nurses and managers

The changing organisation and governance of healthcare work represents a persistent focus of micro-politics. Whilst there is a developed literature describing the micro-politics struggles that occur amongst health occupations, there is little understanding about how actors become politically aware and active. Framed by research on political activation and the concept of identity work, the paper reports on a narrative interview study with 65 people, specifically doctors, nurses and managers, working in the English healthcare system. The narratives show that healthcare workers become increasingly aware of and engaged in micro-political activities through incremental stages based on their accumulating experiences. These stages are opportunities for identity work as actors make sense of their experiences of micro-politics, their occupational affiliations and their evolving sense of self. This identity work is shaped by actors changing views about the morality of playing politics, the emotional implications of their engagement, and the deepening political commitments. The study shows that political socialisation and activation can vary between occupations and rather than assuming political affiliations are given or acquired the papers highlights the reflective agency of healthcare actors

Comparison of heterotrophic bioleaching and ammonium sulfate ion exchange leaching of Rare Earth Elements from a Madagascan Ion-Adsorption Clay

Rare earth elements (REE) are considered to be a critical resource, because of their importance in green energy applications and the overdependence on Chinese imports. REE rich ion-adsorption deposits (IAD) result from tropical weathering of REE enriched igneous rocks. Commercial REE leaching from IAD, using salt solutions occurs via an ion-exchange mechanism. Bioleaching of IAD by Aspergillus or Bacillus, was compared to Uninoculated Control and Salt leaching (0.5 M ammonium sulfate) over 60 days. Salt leaching was most effective, followed by Aspergillus, Bacillus then Uninoculated Control. Most of the REE and major elements released by Salt leaching occurred before day 3. With bioleaching, REE and major elements release increased with time and had a greater heavy to light REE ratio. Similar total heavy REE release was observed in Salt leaching and Aspergillus (73.1% and 70.7% Lu respectively). In bioleaching experiments, pH was inversely correlated with REE release (R2 = 0.947 for Lu) indicating leaching by microbially produced acids. These experiments show the potential for bioleaching of REE from IAD, but dissolution of undesirable elements could cause problems in downstream processing. Further understanding of the bioleaching mechanisms could lead to optimization of REE recover

Perturbations of Dirac operators

We study general conditions under which the computations of the index of a perturbed Dirac operator $D_{s}=D+sZ$ localize to the singular set of the bundle endomorphism $Z$ in the semi-classical limit $s\to \infty$. We show how to use Witten's method to compute the index of $D$ by doing a combinatorial computation involving local data at the nondegenerate singular points of the operator $Z$. In particular, we provide examples of novel deformations of the de Rham operator to establish new results relating the Euler characteristic of a spin$^{c}$ manifold to maps between its even and odd spinor bundles. The paper contains a list of the current literature on the subject.Comment: 34 pages, improved results, new applications, literature list update

The effects of experimenter-participant interaction qualities in a goal-oriented nonintentional precognition task

Several recent studies, inspired by psi theories such as Stanford’s psi-mediated instrumental response (PMIR) model, have employed a tacit precognition protocol to test the notion that extrasensory perception may be nonintentional. After remarkable initial success, outcomes have been more inconsistent. One possible reason for the observed variability in results is that the studies were conducted by different experimenters. The current study therefore addressed a number of dimensions regarding participants’ interaction with either a male or female experimenter. 52 participants took part in 12 nonintentional precognition trials and a positive or negative outcome task contingent on their performance. The total number of precognitive hits was marginally above mean chance expectation but failed to reach statistical significance. There were significant positive correlations between participants’ precognition scores and their ratings of the positivity of their interaction with the experimenter, their rapport with the experimenter, and their level of relaxation. There were also notable differences between the two experimenters with respect to the relationships between their participant-experimenter interaction ratings and participants’ tacit precognition scores; all correlations were in the predicted direction for the female experimenter, but in the opposite direction for the male experimenter

Twenty-year outcomes of a longitudinal prospective evaluation of isolated endoscopic anterior cruciate ligament reconstruction with patellar tendon autografts

Background: Long term prospective follow up studies of single-incision endoscopic anterior cruciate ligament reconstruction are limited and may include confounding factors. Objectives: This longitudinal prospective study reports the outcome of isolated anterior cruciate ligament (ACL) reconstruction using middle-third patellar tendon autograft in 90 patients over 20 years. Study design: Case series; Level of evidence, 4. Methods: Between January 1993 and April 1994, 90 patients met study inclusion criteria, evaluation 1,2,3,4,5,7,10,15 and 20 years post-surgery. Exclusion criteria: associated ligamentous injury requiring surgery, previous meniscectomy; meniscal injury meniscectomy more than 1/3; chondral injury; and an abnormal contralateral knee. Results: At 20 years, 32(36%) patients had sustained another ACL injury, 8(9%) to the index limb and 27(29%) to the contralateral limb (3 injuring both knees). Mean IKDC score was 86, 50% participated in strenuous/very strenuous activities, kneeling pain was present in 63%. Radiographic degenerative change was found in 61%, 20% IKDC Grade C, 0% Grade D. IKDC clinical examination revealed 95% had a normal/nearly normal knee. Significant gender differences existed: females were less likely to re-injure the reconstructed ACL (18%v2%, p=0.01), reported poorer IKDC subjective score (90v83, p=0.03), had more activity related pain (57%v20%, p=0.02), and less likely to participate in strenuous activity (35v66, p=0.01). ACL graft survival was not related to age. Patients \u3c18years old had an increased odd ratio (3.2) for rupturing the contralateral ACL. Coronal graft angles \u3c17 degrees had increased risk of failure compared to those over 17 degrees (96% v 77%), by a factor of 8.5. Conclusion: Injury commonly occurred in the contralateral ACL than the reconstructed ACL graft, the most significant predictor of contralateral ACL injury is age under 18yrs. The most significant predictor of ACL graft rupture is a coronal graft angle of less than 17 degrees. Females had lower re- rupture rates, poorer subjective scores, decreased participation in strenuous activity, putting the graft at less risk of failure. Kneeling pain remained persistent over 20 years. Radiographic osteoarthritis was evident in 61% of subjects but symptomatic osteoarthritic symptoms were rarely reported

Comparison of Three Approaches for Bioleaching of Rare Earth Elements from Bauxite

Approximately 300 million tonnes of bauxite are processed annually, primarily to extract alumina, and can contain moderate rare earth element (REE) concentrations, which are critical to a green energy future. Three bioleaching techniques (organic acid, reductive and oxidative) were tested on three karst bauxites using either Aspergillus sp. (organic acid bioleaching) or Acidithiobacillus ferrooxidans (reductive and oxidative bioleaching). Recovery was highest in relation to middle REE (generally Nd to Gd), with maximum recovery of individual REE between 26.2% and 62.8%, depending on the bauxite sample. REE recovery occurred at low pH (generally < 3), as a result of organic acids produced by Aspergillus sp. or sulphuric acid present in A. ferrooxidans growth media. Acid production was seen when A. ferrooxidans was present. However, a clear increase in REE recovery in the presence of A. ferrooxidans (compared to the control) was only seen with one bauxite sample (clay-rich) and only under oxidative conditions. The complex and varied nature of REE-bearing minerals in bauxite provides multiple targets for bioleaching, and although the majority of recoverable REE can be leached by organic and inorganic acids, there is potential for enhanced recovery by bioleaching

Implementing human factors in clinical practice

OBJECTIVES: To understand whether aviation-derived human factors training is acceptable and useful to healthcare professionals. To understand whether and how healthcare professionals have been able to implement human factors approaches to patient safety in their own area of clinical practice. METHODS: Qualitative, longitudinal study using semi-structured interviews and focus groups, of a multiprofessional group of UK NHS staff (from the emergency department and operating theatres) who have received aviation-derived human factors training. RESULTS: The human factors training was evaluated positively, and thought to be both acceptable and relevant to practice. However, the staff found it harder to implement what they had learned in their own clinical areas, and this was principally attributed to features of the informal organisational cultures. CONCLUSIONS: In order to successfully apply human factors approaches in hospital, careful consideration needs to be given to the local context and informal culture of clinical practice