Timing is everything; operational changes at a pumping station with a gravity sluice to provide safe downstream passage for silver European eels and deliver considerable financial savings.

Catadromous European eel (Anguilla anguilla) are a critically endangered fish species due in part to in-river anthropogenic barriers (e.g., pumping stations, weirs, hydropower facilities). European legislation stipulates that safe downstream passage must be provided at hazardous intakes. Where present, gravity sluices have the potential to act as safe and low-cost downstream passage for seaward migrating silver eels at pumping station, but operational changes are required. This study used catchment-wide and fine-scale acoustic telemetry to investigate if operational changes (OC) at a pumping station (PS) with a co-located gravity sluice (GS) facilitated safe downstream passage for silver European eels. Specifically, night-time pump operations were ceased, river levels prior to sluicing were elevated and the GS was opened during key eel migration windows, i.e., at night during the new moon phase in autumn. No tagged eels passed through any pumps and the majority (2018 = 87.5%, 2020 = 88.9%) that approached the PS during OC passed downstream through the GS. Most eels approached during the first period of night sluicing after release (2018 = 73.9% and 2020 = 76.5%) and passed downstream during the first sluice event they experienced at the PS (2018 = 66.7% and 2020 = 75.0%). During the final approach prior to passage, very few retreats back upstream occurred at a median (IQR) distance of 34 (7.25) m from the GS and were predominantly a short distance (1-8 m). Overall, OC at a PS with a GS are considered a win-win-win, despite opening the sluice for <3% of the study period, given safe downstream passage was maximised, the financial benefits of sluicing water (∼£14,670 in direct operational costs over two years) and the relative ease of implementation.

Testing the public's response to receiving severe flood warnings using simulated cell broadcast.

European Governments must implement a public alerting system to reach mobile phone users affected by major emergencies and disasters by June 2022. Cell Broadcast is used to issue emergency alerts in several countries but has not yet been introduced in the UK. This paper presents the results of a joint research exercise that explored recipients' responses to cell broadcast messages that warned of floods of varying certainty, severity, and urgency. We adopted a mixed-methods approach employing semi-structured questions and focus groups to assess the perceptions of 80 workshop participants who received simulated emergency alerts on pre-prepared handsets. Our results suggest that although emergency alerting is welcomed, it is necessary to provide accurate and verifiable information, address accessibility challenges, and state location clearly and understandably. This life-saving technology, if used aptly by not over-alerting, specifying the specific urgency, certainty, severity and location of the flood risk, has the real potential of upgrading flood warnings in the UK.

Correction to 'Individual-based model of juvenile eel movement parametrized with computational fluid dynamics derived flow fields informs improved fish pass design'.

[This corrects the article DOI: 10.1098/rsos.191505.].

Individual-based model of juvenile eel movement parametrized with computational fluid dynamics-derived flow fields informs improved fish pass design.

European eel populations have declined markedly in recent decades, caused in part by in-stream barriers, such as weirs and pumping stations, which disrupt the upstream migration of juvenile eels, or elvers, into rivers. Eel passes, narrow sloping channels lined with substrata that enable elvers to ascend, are one way to mitigate against these barriers. Currently, studded eel tiles are a popular substrate. This study is the first to evaluate the flow fields within studded eel tiles and to model the swimming performance of elvers using cellular automata (CA) and individual- (or agent-) based models. Velocities and flow depths predicted by a computational fluid dynamics model of studded eel tiles are first validated against published values for a single installation angle-discharge combination. The validated model is then used to compute three-dimensional flow fields for eel passes at five different installation angles and three inflow discharges. CA and individual-based models are employed to assess upstream passage efficiency for a range of elver sizes. The individual-based model approximates measured passage efficiencies better than the CA model. Passage efficiency is greatest for shallow slopes, low discharges and large elvers. Results are synthesized into an easy-to-understand graphic to help practitioners improve eel pass designs.

Analytic nuclear forces and molecular properties from full configuration interaction quantum Monte Carlo.

Unbiased stochastic sampling of the one- and two-body reduced density matrices is achieved in full configuration interaction quantum Monte Carlo with the introduction of a second, "replica" ensemble of walkers, whose population evolves in imaginary time independently from the first and which entails only modest additional computational overheads. The matrices obtained from this approach are shown to be representative of full configuration-interaction quality and hence provide a realistic opportunity to achieve high-quality results for a range of properties whose operators do not necessarily commute with the Hamiltonian. A density-matrix formulated quasi-variational energy estimator having been already proposed and investigated, the present work extends the scope of the theory to take in studies of analytic nuclear forces, molecular dipole moments, and polarisabilities, with extensive comparison to exact results where possible. These new results confirm the suitability of the sampling technique and, where sufficiently large basis sets are available, achieve close agreement with experimental values, expanding the scope of the method to new areas of investigation.

Accurate Ab initio calculation of ionization potentials of the first-row transition metals with the configuration-interaction quantum Monte Carlo technique.

Accurate ionization potentials of the first-row transition-metal atoms are obtained via the initiator full configuration quantum Monte Carlo technique, performing a stochastic integration of the electronic Schrödinger equation in exponentially large Hilbert spaces, with a mean absolute error of 0.13 kcal/mol (5 meV). This accuracy requires correlation of the 3p semicore electrons and in some cases the 3s manifold, along with extrapolation of the correlation energies to the complete-basis-set limit, and provides a new theoretical benchmark for the ionization potentials of these systems.

Incidence of Intravenous Medication Errors in a Chinese Hospital.

OBJECTIVES: The purpose of this study was to explore intravenous (IV) medication errors in a Chinese hospital. The specific objectives were to 1) explore and measure the frequency of IV medication errors by direct observation and identify clues to their causes in Chinese hospital inpatient wards and 2) identify the clinical importance of the errors and find the potential risks in the preparation and administration processes of IV medications. METHODS: A prospective study was conducted by using the direct observational method to describe IV medication errors on two general surgery patient wards in a large teaching hospital in Beijing, China. A trained observer accompanied nurses during IV preparation rounds to detect medication errors. The difference in mean error rates between total parenteral nutrition (TPN) and non-TPN medications was tested by using the Mann-Whitney U test. RESULTS: A final total of 589 ordered IV doses plus 4 unordered IV doses as prepared and administered to the patients was observed from August 3, 2010, to August 13, 2010. The overall error rate detected on the study ward was 12.8%. The most frequent errors by category were wrong dose (5.4%), wrong time (3.7%), omission (2.7%), unordered dose (0.7%), and extra dose (0.3%). Excluding wrong time errors, the error rate was 9.1%. Non-TPN medications had significantly higher error rates than did TPN medications including wrong time errors (P = 0.0162). CONCLUSIONS: A typical inpatient in a Chinese hospital was subject to about one IV error every day. Pharmacists had a very limited role in ensuring the accuracy of IV medication preparation and administration processes.

Stochastic Multiconfigurational Self-Consistent Field Theory.

The multiconfigurational self-consistent field theory is considered the standard starting point for almost all multireference approaches required for strongly correlated molecular problems. The limitation of the approach is generally given by the number of strongly correlated orbitals in the molecule, since its cost will grow exponentially with this number. We present a new multiconfigurational self-consistent field approach, wherein linear determinant coefficients of a multiconfigurational wave function are optimized via the stochastic full configuration interaction quantum Monte Carlo technique at greatly reduced computational cost, with nonlinear orbital rotation parameters updated variationally based on this sampled wave function. This extends this approach to strongly correlated systems with far larger active spaces than it is possible to treat via conventional means. By comparison with this traditional approach, we demonstrate that the introduction of stochastic noise in both the determinant amplitudes and the gradient and Hessian of the orbital rotations does not preclude robust and reliable convergence of the orbital optimization. It can even improve the ability to avoid convergence to local minima in the orbital space, and therefore aid in finding variationally lower-energy solutions. We consider the effect on the convergence of the orbitals as the number of walkers and the sampling time within the active space increases, as well as the effect on the final energy and error. The scope of the new protocol is demonstrated with a study of the increasingly strongly correlated electronic structure in a series of polycyclic aromatic hydrocarbons, up to the large coronene molecule in a complete active space of 24 π electrons in 24 orbitals, requiring only modest computational resources

Symmetry Breaking and Broken Ergodicity in Full Configuration Interaction Quantum Monte Carlo.

The initiator full configuration interaction quantum Monte Carlo method (i-FCIQMC) is applied to the binding curve of N2 in Slater-determinant Hilbert spaces formed of both canonical restricted Hartree-Fock (RHF) and symmetry-broken unrestricted Hartree-Fock (UHF) orbitals. By explicit calculation, we demonstrate that the technique yields the same total energy for both types of orbital but that as the bond is stretched, FCI expansions expressed in unrestricted orbitals are substantially more compact than their restricted counterparts and more compact than those expressed in split-localized orbitals. These unrestricted Hilbert spaces, however, become nonergodic toward the dissociation limit, and the total wave function may be thought of as the sum of two weakly coupled, spin-impure, functions whose energies are nonetheless very close to the exact energy. In this limit, it is a challenge for i-FCIQMC to resolve a spin-pure wave function. The use of unrestricted natural orbitals is a promising remedy for this problem, as their expansions are more strongly weighted toward lower excitations of the reference, and they provide stronger coupling to higher excitations than do UHF orbitals.

Comparison of two error-detection methods in a mail service pharmacy serving health facilities.

OBJECTIVES: To compare two dispensing error-detection methods in a mail service pharmacy and explore clues to the causes of near errors. DESIGN: Descriptive and exploratory study. SETTING: Mail service pharmacy serving health facilities, April 5-9, 2004. PARTICIPANTS: Technicians, pharmacists at a mail service pharmacy; nurses at health facilities served. INTERVENTION: Blinded, undisguised observation of prescription orders at a mail service pharmacy by a research pharmacist and student pharmacist. MAIN OUTCOME MEASURES: Prescription dispensing errors detected by pharmacist audit compared with errors reported by nurses at the health facilities served. RESULTS: Of the 3,337 prescription orders sampled, 16 (0.48%) contained one or more errors based on the observers' assessment and no errors were reported by nurses for these medications using incident reports. Error types detected by observation were compared with the data from incident reports for the 3 previous years. Extrapolating the findings of the observational study and comparing those data with the incident reports, significant differences were found for total dispensing errors, wrong strength errors, wrong dosage form errors, and wrong label instruction errors. Errors related to wrong drug were not significantly different between the observational and incidentreporting data. In observations of pharmacists at work in the mail-service pharmacy, proximity of look-alike/sound-alike drugs on storage shelves and inadequate lighting were potential causes of near errors. CONCLUSION: Pharmacist assessment of prescription orders detects more dispensing errors than nurse-based incident reports. The study identified clues to the causes of near errors occurring in a mail service pharmacy.

Quality control chart method for analyzing PEF variability in occupational asthma.

BACKGROUND: Asthma is the most common occupational respiratory disorder in the industrialized world. In this research we investigated the effectiveness of quality control chart as a method to explore the work-relatedness of asthma using peak expiratory flow (PEF) as the variable of interest. METHOD: PEF measurements were recorded from several workers suspected of having occupational asthma. The measurements were recorded for a period of 2 weeks at work and two away from work. For each subject, average [symbol: see text] quality control chart was developed and analyzed using Shewhart methods. RESULTS: Using the ratio of average daily PEF diurnal variation at work to the baseline average diurnal variation, quality control chart detected and characterized increased variation in PEF between the periods at workplace and away from workplace. This ratio was evaluated at 15% and 20% and compared to the results of the gold standard. A ratio of greater than 15% produced a sensitivity of 94% and specificity of 61%. These results are as good as and in some cases better than the previously published work. CONCLUSIONS: Quality control chart is an effective and inexpensive method for early intervention to detect workers suspected for occupational asthma. Also, the findings in this article are an invitation for further research in occupational asthma using quality control chart methods for other indices of airways obstruction (FEV-1, RAW) or inflammation (NO).

Induction of DNA strand breaks in the mussel (Mytilus trossulus) and clam (Protothaca staminea) following chronic field exposure to polycyclic aromatic hydrocarbons from the Exxon Valdez spill.

In 2002, 13 years after the Exxon Valdez spill, mussels and clams were examined for lingering oil exposure and damage. Known oil patches were sampled at four locations, and compared to nearby reference areas (same bay), and were also compared to "hot reference" sites to verify the methods used (Cordova harbor and fresh diesel spill at Port Chalmers). Passive samplers deployed for a month at the sites, along with tissue samples, confirmed that the oiled sites were oiled (fingerprinting back to Exxon Valdez oil) and that reference sites were clean. The highest PAH loads were detected in sub-surface interstitial waters at oiled sites. Exposure at the surface was generally low level, and probably intermittent. DNA damage was assessed in blood cells using sensitive comet analyses. DNA strand breakage was detected in both mussels and clams, with the highest level of damage detected at "hot reference" sites of Cordova harbor and Port Chalmers. Bioavailability and DNA damage at the oiled sties was low, indicating there has been substantial progress in recovery from the spill 13 years before, yet low level bioavailability and damage were still detectable.

Ergonomics evaluation of a government office building.

An ergonomics team from the US Army Center for Health Promotion and Preventive medicine evaluated 465 video display terminal (VDT) workstations in a Government office building over an 18-day period. Each workstation evaluation involved an assessment of the worker, the chair, the desk, the keyboard, the pointing device, the monitor, and the office environmental conditions. The team also collected worker pain and injury information. The problems seen during the evaluation were characteristic of most office environments where VDT workstation furniture was purchased before the advent of mouse-driven software. The majority of furniture evaluated was not designed to meet the demands of intensive mouse use for prolonged periods of time. Much of the workstation furniture was not adjustable, chairs lacked adequate back support, and workers assumed non-neutral postures. As a result, more than 35% of the workers evaluated complained of on-the-job pain. New office furniture that is adjustable, adequate desk space and storage space were among the solutions recommended by the ergonomics team.