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1.
ACS Omega ; 9(18): 20454-20466, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38737035

ABSTRACT

This study investigates the kinetics of salt mixture crystallization under relative humidity (RH) conditions, varying between 15 and 95% (at 20 °C), to inform applications in built heritage preservation, geology, and environmental sciences. We focused on commonly found, sulfate-rich and calcium-rich salt mixtures containing five to six ions, Cl-, NO3-, Na+, and K+, including or excluding less common Mg2+, and including either an excess of SO42- or Ca2+, with respect to gypsum. Using time-lapse micrographs and dynamic vapor sorption, we explore how crystallization and dissolution behavior depend on RH and mixture composition under constant temperature. A range of RH change rates were studied to simulate realistic weather events. Microstructural analyses through environmental scanning electron microscopy (ESEM) confirmed the crystal habit corresponding with RH transitions. Phases predicted from thermodynamic modeling (ECOS/RUNSALT) were confirmed using micro-Raman spectroscopy, X-ray diffraction (XRD), and elemental mapping via energy-dispersive X-ray spectroscopy (EDX). We identify a strong correlation between phase transition kinetics and RH change rates, with crystallization deviating by -15% and dissolution by +7% from modeled values under rapid (several seconds) and slow (several days) RH changes. These insights are important for preservation strategies in built heritage, salt deposition, and dissolution mechanisms in diverse geological and realistic environmental contexts, laboratory experiments, future modeling efforts, and the understanding of stone decay in general.

2.
Environ Pollut ; 343: 123128, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38097158

ABSTRACT

Despite the increasing concerns surrounding the health and environmental risks of microplastics (MPs), the research focus has primarily been on their prevalence in air and the oceans, consequently neglecting their presence on urban facades, which are integral to our everyday environments. Therefore, there is a crucial knowledge gap in comprehending urban MP pollution. Our pioneering interdisciplinary study not only quantifies but also identifies MPs on historic facades, revealing their pervasive presence in a medium-sized urban area in the UK. In this case study, we estimated a mean density of 975,000 fibres/m^2 (0.10 fibres/mm^2) for fibre lengths between 30 and 1000 µm with a ratio of 1:5 for natural to artificial fibres. Our research identifies three groups of fibre length frequencies across varied exposure scenarios on the investigated urban facade. Sheltered areas (4m height) show a high prevalence of 60-120 µm and 180-240 µm fibres. In contrast, less sheltered areas at 3m exhibit lower fibre frequencies but similar lengths. Notably, the lowest area (2-1.5m) features longer fibres (300-1000 µm), while adjacent area S, near a faulty gutter, shows no fibres, highlighting the impact of exposure, altitude, and environmental variables on fibre distribution on urban facades. Our findings pave one of many necessary paths forward to determine the long-term fate of these fibres and provoke a pertinent question: do historic facades serve as an urban 'sink' that mitigates potentially adverse health impacts or amplifies the effects of mobile microplastics? Addressing MP pollution in urban areas is crucial for public health and sustainable cities. More research is required to understand the multi-scale factors behind MP pollution in large cities and to find mitigation strategies, paving the way for effective interventions and policies against this growing threat.


Subject(s)
Microplastics , Water Pollutants, Chemical , Plastics , Environmental Pollution , Cities , Oceans and Seas , Environmental Monitoring , Water Pollutants, Chemical/analysis
3.
Sci Rep ; 13(1): 13306, 2023 Aug 16.
Article in English | MEDLINE | ID: mdl-37587170

ABSTRACT

Salt related weathering of stones has been attributed to pressures exerted by repeated cycles of crystallization within pores. Relative Humidity (RH) is a key driver for dissolution and crystallization processes. Despite the prevalence of salt mixtures in natural environments, most experimental work has focused on single salts. Thus, the identification of salt mixture composition and their behavior is necessary to understand weathering. Thermodynamic calculations are used to analyze several thousand realistic salt mixtures found in weathered stone. We identify two common mixture types and their behavior. From at least 85 salt species theoretically present, 14 common salts are identified that occur most frequently and their critical RH points are discussed. These findings have wide-reaching implications for understanding salt weathering processes and informing the design of experimental stone weathering research.

4.
Mem Inst Oswaldo Cruz ; 118: e220263, 2023.
Article in English | MEDLINE | ID: mdl-37222309

ABSTRACT

BACKGROUND: Vaccine development is a laborious craftwork in which at least two main components must be defined: a highly immunogenic antigen and a suitable delivery method. Hence, the interplay of these elements could elicit the required immune response to cope with the targeted pathogen with a long-lasting protective capacity. OBJECTIVES: Here we evaluate the properties of Escherichia coli spherical proteoliposomes - known as outer membrane vesicles (OMVs) - as particles with natural adjuvant capacities and as antigen-carrier structures to assemble an innovative prophylactic vaccine for Chagas disease. METHODS: To achieve this, genetic manipulation was carried out on E. coli using an engineered plasmid containing the Tc24 Trypanosoma cruzi antigen. The goal was to induce the release of OMVs displaying the parasite protein on their surface. FINDINGS: As a proof of principle, we observed that native OMVs - as well as those carrying the T. cruzi antigen - were able to trigger a slight, but functional humoral response at low immunization doses. Of note, compared to the non-immunized group, native OMVs-vaccinated animals survived the lethal challenge and showed minor parasitemia values, suggesting a possible involvement of innate trained immunity mechanism. MAIN CONCLUSION: These results open the range for further research on the design of new carrier strategies focused on innate immunity activation as an additional immunization target and venture to seek for alternative forms in which OMVs could be used for optimizing vaccine development.


Subject(s)
Chagas Disease , Escherichia coli , Animals , Antigens, Protozoan , Immunity, Innate , Parasitemia
5.
Mem. Inst. Oswaldo Cruz ; 118: e220263, 2023. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1440673

ABSTRACT

BACKGROUND Vaccine development is a laborious craftwork in which at least two main components must be defined: a highly immunogenic antigen and a suitable delivery method. Hence, the interplay of these elements could elicit the required immune response to cope with the targeted pathogen with a long-lasting protective capacity. OBJECTIVES Here we evaluate the properties of Escherichia coli spherical proteoliposomes - known as outer membrane vesicles (OMVs) - as particles with natural adjuvant capacities and as antigen-carrier structures to assemble an innovative prophylactic vaccine for Chagas disease. METHODS To achieve this, genetic manipulation was carried out on E. coli using an engineered plasmid containing the Tc24 Trypanosoma cruzi antigen. The goal was to induce the release of OMVs displaying the parasite protein on their surface. FINDINGS As a proof of principle, we observed that native OMVs - as well as those carrying the T. cruzi antigen - were able to trigger a slight, but functional humoral response at low immunization doses. Of note, compared to the non-immunized group, native OMVs-vaccinated animals survived the lethal challenge and showed minor parasitemia values, suggesting a possible involvement of innate trained immunity mechanism. MAIN CONCLUSION These results open the range for further research on the design of new carrier strategies focused on innate immunity activation as an additional immunization target and venture to seek for alternative forms in which OMVs could be used for optimizing vaccine development.

6.
Sci Data ; 9(1): 324, 2022 06 17.
Article in English | MEDLINE | ID: mdl-35715411

ABSTRACT

Understanding salt mixtures in the built environment is crucial to evaluate damage phenomena. This contribution presents charge balance calculations applied to a dataset of 11412 samples taken from 338 sites, building materials showing signs of salt deterioration. Each sample includes ion concentrations of Na+, K+, Mg2+, Ca2+, Cl-, NO3-, and SO42- adjusted to reach charge balance for data evaluation. The calculation procedure follows two distinct pathways: i) an equal adjustment of all ions, ii) adjustments to the cations in sequence related to the solubility of the theoretical solids. The procedure applied to the dataset illustrates the quantification of salt mixture compositions and highlights the extent of adjustments applied in relation to the sample mass to aid interpretation. The data analysis allows the identification of theoretical carbonates that could influence the mixture behavior. Applying the charge balance calculations to the dataset validated common ions found in the built environment and the identification of three typical mixture compositions. Additionally, the data can be used as direct input for thermodynamic modeling.

7.
BMJ Qual Saf ; 31(7): 493-502, 2022 07.
Article in English | MEDLINE | ID: mdl-34417333

ABSTRACT

BACKGROUND: Given rising costs and changing payment models, healthcare organisations are increasingly focused on value and efficiency. The goal of our study was to develop survey items to assess clinician and staff perspectives about the extent to which the organisational culture in hospitals and medical offices supports value and efficiency. METHODS: Development began with a literature review and interviews with experts and clinicians and staff from hospitals and medical offices. We identified key areas of value and efficiency culture, drafted survey items and conducted cognitive testing. Using purposive sampling to select sites, the 36-item surveys were pilot tested in 47 hospitals and 96 medical offices. Psychometric analysis was conducted on data from 3951 hospital respondents (42% response) and 1458 medical office respondents (63% response). RESULTS: Factor loadings, multilevel confirmatory factor analysis model fit and reliability estimates were acceptable for the 13 items grouped into 4 composite measures: Empowerment to Improve Efficiency (3 items), Efficiency and Waste Reduction (3 items), Patient Centeredness and Efficiency (3 items) and Management Support for Improving Efficiency and Reducing Waste (4 items). All composite measures were significantly intercorrelated and related to the four Overall Ratings of Healthcare Quality, indicating adequate conceptual convergence among the measures. Eight items assessing Experiences With Activities to Improve Efficiency were also included. CONCLUSION: We developed psychometrically sound survey items measuring value and efficiency culture. When added to the Agency for Healthcare Research and Quality Surveys on Patient Safety Culture, the item sets extend those surveys by assessing additional dimensions of organisational culture that affect care delivery. Healthcare organisations can use these item sets to assess how well their organisational culture supports value and efficiency and identify areas for improvement.


Subject(s)
Organizational Culture , Safety Management , Hospitals , Humans , Psychometrics , Reproducibility of Results , Surveys and Questionnaires
8.
Sci Total Environ ; 759: 143916, 2021 Mar 10.
Article in English | MEDLINE | ID: mdl-33338691

ABSTRACT

Black crusts on historic buildings are mainly known for their aesthetic and deteriorative impacts, yet they also can advance air pollution research. Past air pollutants accumulate in distinct layers of weathering crusts. Recent studies have used these crusts to reconstruct pollution to improve our understanding of its effects on stone-built heritage. However, the majority of the studies provide only coarse resolution reconstruction of pollution, able to distinguish between 'inner = old' and 'outer = modern' crust layers. In contrast, very few studies have linked distinct periods of exposure to pollution variations in the composition of these crusts. Here we address this research gap by developing a finer-scale resolution pollution record. Our study explored the unique configuration of limestone sculptures in central Oxford, which have been exposed over the last 350 years to three different periods of atmospheric pollution; the early Industrial Revolution, the Victorian period and the 20th century. When the first two generations of sculptures were moved to less polluted areas, their 'pollution clocks' were stopped. Here we discuss the potential of investigating the 'pollution clock' recorded in the geochemical makeup of each sculpture generation's weathering crust layers. We found the analysed crusts record clear changes related to the evolution of modes of transport and industrial and technological development in Oxford. Higher levels of Arsenic (As), Selenium (Se) are linked to pollution from coal burning during Victorian times and Lead (Pb) indicated leaded petrol use in modern times. Our work shows that stone-built heritage with a known history of air pollution exposure allows improving the pollution reconstruction resolution of these weathering crusts. The results provide the basis for calibrating long-term geochemical archives. This approach may be used to reconstruct past air quality and has the potential to inform stone weathering research and conservation, in addition to improving the reconstruction of historical pollution.

9.
Arthroscopy ; 35(3): 871-873, 2019 03.
Article in English | MEDLINE | ID: mdl-30827439

ABSTRACT

The opioid crisis is real, and orthopaedic surgeons are at the top of the list of overall opioid prescribers. As orthopaedic surgeons, we need to realize the broad spectrum of the problem, take ownership of our faults, and identify how each of us can individually put processes into our own practices to help find a solution to the problem.


Subject(s)
Analgesics, Opioid , Orthopedic Surgeons , Anti-Inflammatory Agents, Non-Steroidal , Humans , Meniscectomy , Prospective Studies
10.
Sci Total Environ ; 640-641: 1098-1111, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-30021275

ABSTRACT

Wind-driven rain (WDR) is rain given a horizontal velocity component by wind and falling obliquely. It is a prominent environmental risk to built heritage, as it contributes to the damage of porous building materials and building element failure. While predicted climate trends are well-established, how they will specifically manifest in future WDR is uncertain. This paper combines UKCP09 Weather Generator predictions with a probabilistic process to create hourly time series of climate parameters under a high-emissions scenario for 2070-2099 at eight UK sites. Exposure to WDR at these sites for baseline and future periods is calculated from semi-empirical models based on long-term hourly meteorological data using ISO 15927-3:2009. Towards the end of the twenty-first century, it is predicted that rain spells will have higher volumes, i.e. a higher quantity of water will impact façades, across all 8 sites. Although the average number of spells is predicted to remain constant, they will be shorter with longer of periods of time between them and more intense with wind-driven rain occurring for a greater proportion of hours within them. It is likely that in this scenario building element failure - such as moisture ingress through cracks and gutter over-spill - will occur more frequently. There will be higher rates of moisture cycling and enhanced deep-seated wetting. These predicted changes require new metrics for wind-driven rain to be developed, so that future impacts can be managed effectively and efficiently.

11.
Drugs Context ; 5: 212296, 2016.
Article in English | MEDLINE | ID: mdl-27403194

ABSTRACT

BACKGROUND: Intra-articular injection of hyaluronic acid (HA) for knee osteoarthritis (OA) effectively reduces pain and delays total knee replacement (TKR) surgery; however, little is known about relative differences in clinical and cost outcomes among different HA products. OBJECTIVE: To compare disease-specific costs and risk of TKR among patients receiving different HA treatments in a commercially insured cohort of patients with knee OA in the USA. METHOD: Retrospective analyses using IMS Health's PharMetrics Plus Health Plan Claims Database were conducted by identifying knee OA patients with claims indicating initiation of HA treatment at an 'index date' during the selection period (2007-2010). Patients were required to be continuously enrolled in the database for 12 months preindex to 36 months postindex. A generalized linear model (GLM) with a gamma distribution and log-link function was used to model aggregate patient-based changes in disease-specific costs. A Cox proportional hazards model (PHM) was used to model the risk of TKR. Both multivariate models included covariates such as age, gender, comorbidities, and preindex healthcare costs. RESULTS: 50,389 patients with HA treatment for knee OA were identified. 18,217 (36.2%) patients were treated with HA products indicated for five injections per treatment course (Supartz and Hyalgan). The remainder were treated with HA products indicated for fewer than five injections per treatment course, with 20,518 patients (40.7%) receiving Synvisc; 6,263 (12.4%), Euflexxa; and 5,391 (10.7%), Orthovisc. Synvisc- and Orthovisc-injected patients had greater disease-specific costs compared to Supartz/Hyalgan (9.0%, p<0.0001 and 6.8%, p=0.0050, respectively). Hazard ratios (HRs) showed a significantly higher risk of TKR for patients receiving Synvisc compared to Supartz/Hyalgan (HR=1.069, p=0.0009). Patients treated with Supartz/Hyalgan, Euflexxa, and Orthovisc had longer delays to TKR than those treated with Synvisc. CONCLUSION: Analysis of administrative claims data provides real-world evidence that meaningful differences exist among some HA products in disease-specific cost and time to knee replacement surgery.

14.
BJPsych Bull ; 39(1): 14-8, 2015 Feb.
Article in English | MEDLINE | ID: mdl-26191418

ABSTRACT

Aims and method The Royal College of Psychiatrists' Committee on Electroconvulsive Therapy (ECT) and Related Treatments advises the measurement of initial seizure threshold in all patients undergoing ECT if possible. The subconvulsive electrical stimulation inherent in this process is thought to increase the risk of bradycardia and therefore asystole. Our aim was to establish the prevalence of asystole (no heart beat for 5 or more seconds) during empirical measurement of seizure threshold in patients who had not received anticholinergic drugs, as we were unable to find any published reports of bradycardia or asystole prevalence under these conditions. The electrocardiogram traces of 50 such consecutive patients were analysed later. Results Asystole occurred in 5% of stimulations. Each episode of asystole resolved spontaneously with no adverse outcomes. Contrary to expectations, asystole was no more prevalent in subconvulsive stimulations than in convulsive stimulations. Clinical implications There was no evidence that the empirical measurement of the seizure threshold added to the cardiovascular risk of ECT.

15.
Neurol Sci ; 36(5): 683-8, 2015 May.
Article in English | MEDLINE | ID: mdl-25604577

ABSTRACT

From an interdisciplinary approach, the neurosciences (NSs) represent the junction of many fields (biology, chemistry, medicine, computer science, and psychology) and aim to explore the structural and functional aspects of the nervous system. Among modern neurophysiological methods that "measure" different processes of the human brain to salience stimuli, a special place belongs to eye tracking (ET). By detecting eye position, gaze direction, sequence of eye movement and visual adaptation during cognitive activities, ET is an effective tool for experimental psychology and neurological research. It provides a quantitative and qualitative analysis of the gaze, which is very useful in understanding choice behavior and perceptual decision making. In the high tech era, ET has several applications related to the interaction between humans and computers. Herein, ET is used to evaluate the spatial orienting of attention, the performance in visual tasks, the reactions to information on websites, the customer response to advertising, and the emotional and cognitive impact of various spurs to the brain.


Subject(s)
Attention/physiology , Eye Movements/physiology , Neurosciences , Reading , Visual Fields/physiology , Humans
19.
J ECT ; 28(3): 162-4, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22513512

ABSTRACT

BACKGROUND: The reasons for the fall in the use of electroconvulsive therapy (ECT) in the United Kingdom have never been systematically assessed. Between 2005 and 2006, the Edinburgh clinic saw the greatest fall ever in the rate of ECT usage between consecutive years. OBJECTIVE: To test the anecdotal hypothesis that this fall resulted from the referral of fewer patients with a diagnosis of severe depression (with or without psychotic symptoms) as per the International Classification of Diseases, 10th Revision. Diagnostic data from 2007 were included to aid comparison. RESULTS: The rates of ECT usage (number of individual patients treated per 10,000 total population) were 1.33, 0.82, and 0.88 in the study years. The numbers of patients with a diagnosis of severe depression of either type were identical in the study years. The fall in the rate of ECT usage resulted mainly from fewer referred patients with a diagnosis of other mood disorders, that is, disorders that did not meet criteria for more specific diagnoses such as depressive episode or bipolar affective disorder. CONCLUSIONS: Just as many severely depressed patients were treated despite the marked fall in the rate of ECT usage.


Subject(s)
Depressive Disorder, Major/therapy , Electroconvulsive Therapy/statistics & numerical data , Referral and Consultation/statistics & numerical data , Adolescent , Adult , Bipolar Disorder/epidemiology , Bipolar Disorder/therapy , Depressive Disorder, Major/epidemiology , Female , Humans , International Classification of Diseases , Male , Middle Aged , Mood Disorders/epidemiology , Mood Disorders/therapy , Psychotic Disorders/epidemiology , Psychotic Disorders/therapy , Retrospective Studies , United Kingdom/epidemiology , Young Adult
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