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1.
J Environ Manage ; 315: 115152, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35525044

RESUMEN

This study reports on a meta-analysis covering the impact of design and operating factors on published MFC performance data to inform MFC research and implementations. Factors of substrate composition, operating phase, electrode material, configuration, and pre-treatments employed were considered. The meta-analysis results indicate that dual-chamber MFCs overall achieve 18% higher COD removal and 73% higher coulombic efficiencies over that of single-chamber MFCs. MFCs using a solid operating phase achieved ˃38% higher coulombic efficiencies than those using a liquid operating phase. Statistical analyses comparing brush vs flat surface anodes revealed that brush anodes can achieve 130% higher power density than flat surface anodes. The use of a platinum catalyst was found to improve power density, as opposed to catalyst-free cathodes. However, coulombic efficiency is less likely to be influenced by the catalyst used and more likely to be dependent on the inclusion of a membrane separator. The meta-analysis results indicate that even in the presence of expensive catalysts like platinum, membrane separators are of prime importance to maintain a stable MFC operation on a long-term basis and achieve high coulombic efficiency in an MFC. Results presented in this paper outline the impact of MFC design choices on performance and can be used to guide future MFC research. These findings can be beneficial for municipalities as it provides a pathway for future MFC design and optimization by analyzing critical associations between MFC response parameters and multiple varying factors.


Asunto(s)
Fuentes de Energía Bioeléctrica , Eliminación de Residuos , Benchmarking , Electricidad , Electrodos , Alimentos , Platino (Metal) , Aguas Residuales/química
2.
J Environ Manage ; 302(Pt A): 113955, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34700088

RESUMEN

Agroforestry has a potentially important role in helping agriculture address both the climate and biodiversity crises. It provides a means of producing additional marketable goods from agricultural land and enhancing biodiversity at the same time as increasing carbon sequestration and, in silvo-pastural systems, reducing carbon emissions if livestock stocking rates are reduced. However, the uptake of agroforestry in the UK has been limited. This paper adopts Real Options techniques to explore how the decision to adopt agroforestry is influenced by the relative levels of returns from agriculture, forestry and the price of carbon under the scenario where there are financial penalties from livestock Greenhouse Gas (GHG) emissions, financial benefits from carbon sequestration in trees and reversibility in land use decisions. The results are compared to the equivalent findings from a Land Equivalent Value capital budgeting approach to agroforestry adoption. Analysis is based on data from a case study upland livestock farm in Scotland, comparing the impacts of introducing agroforestry into the hill sheep enterprise or the low ground cattle and sheep enterprise. The results suggest that the adoption of agroforestry is far less likely than would be suggested by standard budgeting approaches, especially in more extensive upland enterprises (hill area) where sequestration benefits are low relative to more productive farmland areas (low ground area). Upfront support payments are shown to increase the likelihood of agroforestry adoption. They also have the effect of reducing the rotation length of forestry in such systems.


Asunto(s)
Agricultura Forestal , Gases de Efecto Invernadero , Agricultura , Animales , Secuestro de Carbono , Bovinos , Gases de Efecto Invernadero/análisis , Ovinos , Árboles
3.
Nursing ; 50(12): 42-46, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33109998

RESUMEN

ABSTRACT: Nurses of color refrain from speaking up when facing racism in their nursing practice from patients, White peers, coworkers, and higher-ups. Racism is the elephant in the room that no one wants to talk about. This article examines the barriers that may prevent nurses of color from speaking openly about racism and encourages all nurses to speak up and out against racism in nursing.


Asunto(s)
Etnicidad/psicología , Enfermeras y Enfermeros/psicología , Racismo , Etnicidad/estadística & datos numéricos , Humanos , Relaciones Interprofesionales , Relaciones Enfermero-Paciente , Enfermeras y Enfermeros/estadística & datos numéricos , Racismo/prevención & control
4.
Epilepsia ; 60(5): 857-871, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31021436

RESUMEN

OBJECTIVE: Establishing a core set of outcomes to be evaluated and reported in intervention trials aims to improve the usefulness of health research. There is no established core outcome set (COS) for childhood epilepsies. The aim of this study was to select a COS to be used in evaluative research of interventions for children with rolandic epilepsy (RE). METHODS: We followed guidance from the COMET (Core Outcome Measures in Effectiveness Trials) Initiative. First, we identified outcomes that had been measured in research through a systematic review. Second, young people with RE, parents, and professionals were invited to take part in a Delphi survey in which participants rated the importance of candidate outcomes. Last, a face-to-face meeting was convened to seek consensus on which outcomes were critical to include and to ratify the final COS. RESULTS: From 37 eligible papers in the review, we identified and included 48 candidate outcomes in the survey. We sent invitations to 165 people registered to take part in the survey; of these, 102 (62%) completed Round 1, and 80 (78%) completed Round 2 (three young people, 16 parents, 61 professionals). In Round 2 we included four additional outcomes suggested by participants in Round 1. The consensus meeting included two young people, four parents, and nine professionals who were eligible to vote and ratified the COS as 39 outcomes across 10 domains. SIGNIFICANCE: Our methodology was a proportionate and pragmatic approach toward producing a COS for evaluating research on interventions aiming to improve the health of children with RE.


Asunto(s)
Técnica Delphi , Epilepsia Rolándica/terapia , Evaluación de Resultado en la Atención de Salud/métodos , Proyectos de Investigación , Revisiones Sistemáticas como Asunto , Adulto , Cuidadores/psicología , Niño , Consenso , Femenino , Personal de Salud/psicología , Humanos , Masculino , Evaluación del Resultado de la Atención al Paciente , Pacientes/psicología , Resultado del Tratamiento
5.
Can J Microbiol ; 62(10): 870-879, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27556282

RESUMEN

Little is known about the microbial communities native to surface-deposited pyritic oil sands tailings, an environment where acid rock drainage (ARD) could occur. The goal of this study was to enrich sulfur-oxidizing organisms from these tailings and determine whether different populations exist at pH levels 7, 4.5, and 2.5. Using growth-based methods provides model organisms for use in the future to predict potential activities and limitations of these organisms and to develop possible control methods. Thiosulfate-fed enrichment cultures were monitored for approximately 1 year. The results showed that the enrichments at pH 4.5 and 7 were established quicker than at pH 2.5. Different microbial community structures were found among the 3 pH environments. The sulfur-oxidizing microorganisms identified were most closely related to Halothiobacillus neapolitanus, Achromobacter spp., and Curtobacterium spp. While microorganisms related to Chitinophagaceae and Acidocella spp. were identified as the only possible iron-oxidizing and -reducing microbes. These results contribute to the general knowledge of the relatively understudied microbial communities that exist in pyritic oil sands tailings and indicate these communities may have a potential role in ARD generation, which may have implications for future tailings management.


Asunto(s)
Alcaligenaceae/aislamiento & purificación , Halothiobacillus/aislamiento & purificación , Consorcios Microbianos/fisiología , Yacimiento de Petróleo y Gas/microbiología , Alcaligenaceae/genética , Microbiología Ambiental , Halothiobacillus/genética , Fracking Hidráulico , Concentración de Iones de Hidrógeno , Tipificación Molecular , Oxidación-Reducción , ARN Ribosómico 16S/genética
6.
BMC Microbiol ; 14: 225, 2014 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-25194715

RESUMEN

BACKGROUND: Perchlorate contamination has been detected in both ground water and drinking water. An attractive treatment option is the use of ion-exchange to remove and concentrate perchlorate in brine. Biological treatment can subsequently remove the perchlorate from the brine. When nitrate is present, it will also be concentrated in the brine and must also be removed by biological treatment. The primary objective was to obtain an in-depth characterization of the microbial populations of two salt-tolerant cultures each of which is capable of metabolizing perchlorate. The cultures were derived from a single ancestral culture and have been maintained in the laboratory for more than 10 years. One culture was fed perchlorate only, while the other was fed both perchlorate and nitrate. RESULTS: A metagenomic characterization was performed using Illumina DNA sequencing technology, and the 16S rDNA of several pure strains isolated from the mixed cultures were sequenced. In the absence of nitrate, members of the Rhodobacteraceae constituted the prevailing taxonomic group. Second in abundance were the Rhodocyclaceae. In the nitrate fed culture, the Rhodobacteraceae are essentially absent. They are replaced by a major expansion of the Rhodocyclaceae and the emergence of the Alteromonadaceae as a significant community member. Gene sequences exhibiting significant homology to known perchlorate and nitrate reduction enzymes were found in both cultures. CONCLUSIONS: The structure of the two microbial ecosystems of interest has been established and some representative strains obtained in pure culture. The results illustrate that under favorable conditions a group of organisms can readily dominate an ecosystem and yet be effectively eliminated when their advantage is lost. Almost all known perchlorate-reducing organisms can also effectively reduce nitrate. This is certainly not the case for the Rhodobacteraceae that were found to dominate in the absence of nitrate, but effectively disappeared in its presence. This study is significant in that it reveals the existence of a novel group of organisms that play a role in the reduction of perchlorate under saline conditions. These Rhodobacteraceae especially, as well as other organisms present in these communities may be a promising source of unique salt-tolerant enzymes for perchlorate reduction.


Asunto(s)
Reactores Biológicos/microbiología , Nitratos/metabolismo , Percloratos/metabolismo , Rhodobacteraceae/metabolismo , Rhodocyclaceae/metabolismo , Cloruro de Sodio/metabolismo , Secuencia de Bases , Biodegradación Ambiental , Intercambio Iónico , Metagenoma/genética , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , Rhodobacteraceae/genética , Rhodocyclaceae/genética , Sales (Química)/metabolismo
7.
Appl Opt ; 53(17): 3647-55, 2014 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-24921128

RESUMEN

A retroreflective imaging system for imaging microscopic targets over macroscopic sampling areas is introduced. Detection of microorganism-bound retroreflector (RR) targets across millimeter-scale samples is implemented according to retroreflection directionality, collimation, and contrast design characteristics. Retroreflection directionality is considered for corner-cube (CC) and spherical geometries. Spherical-RRs improve directionality and reliability. Retroreflection collimation is considered for spherical-RRs. Retroreflective images for micro-CC-RRs and micro-spherical-RRs with varying refractive indices show optimal results for high refractive index BaTiO3 micro-spherical-RRs. A differential imaging technique improves retroreflection contrast by 35 dB. High refractive index micro-spherical-RRs and differential imaging, together, can detect microscopic RR targets across macroscopic areas.

8.
Environ Sci Technol ; 47(15): 8666-73, 2013 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-23789987

RESUMEN

Salt-tolerant perchlorate-reducing bacteria can be used to regenerate ion-exchange brines or resins exhausted with perchlorate. A salt-tolerant perchlorate-reducing Marinobacter vinifirmus strain P4B1 was recently purified. This study determined the effects of Na(+) and Mg(2+) concentrations on the perchlorate reduction rate of P4B1. The results showed that strain P4B1 could utilize perchlorate and grow in the presence of 1.8% to 10.2% NaCl. Lower NaCl concentrations allowed faster perchlorate reduction. The addition of Mg(2+) to the culture showed significant effects on perchlorate reduction when perchlorate was the sole electron acceptor. A molar Mg(2+)/Na(+) ratio of ∼0.11 optimized perchlorate degradation and cell growth. When perchlorate and nitrate were both present, nitrate reduction did not start significantly until perchlorate was below 100 mg/L. Tests with washed cell suspensions indicated that strain P4B1 had both perchlorate and nitrate reduction enzymes. When the culture was exposed to both perchlorate and nitrate, the nitrate reduction enzyme activity was low. The maximum specific substrate utilization rate (Vm) and the half saturation coefficient (KS) for P4B1 (30 g/L NaCl) determined in this study were 0.049 ± 0.003 mg ClO4(-)/mg VSS-h and 18 ± 4 mg ClO4(-)/L, respectively.


Asunto(s)
Adaptación Fisiológica , Magnesio/química , Marinobacter/metabolismo , Nitratos/química , Percloratos/metabolismo , Cloruro de Sodio/metabolismo , Sodio/química , Cinética , Marinobacter/fisiología , Oxidación-Reducción
9.
Bioresour Technol ; 374: 128778, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36841397

RESUMEN

Food waste generation and its consequent environmental impacts are increasing due to rapid urbanization, the global population, and associated food demand. Microbial fuel cells (MFCs) are a sustainable technology through which this food waste can be treated and used to produce bioelectricity. This study used two MFC configurations, a two-stage anaerobic up-flow leachate reactor MFC and a single-stage MFC, comparing the potential to treat solid fruit waste and fruit waste leachate. The two-stage MFC showed a higher potential to remove substrate at a shorter time compared to single-stage MFC. In 30 days, the two-stage anaerobic up-flow leachate reactor had a power density of 221 mW/m2. It was able to remove more total solids (by 95 %), volatile solids (by 70 %), total chemical oxygen demand (by 83 %), soluble chemical oxygen demand (by 87 %), and carbohydrates (by 33 %) compared to the single-stage MFC. However, the single-stage MFC showed higher coulombic efficiency (by 86.7 %) compared to the two-stage MFC. The efficiency of single-stage MFC improved by adding buffer and maintaining a neutral pH level of the substrate. The results of this study emphasize the importance of reactor design and demonstrate that MFC can be a viable technology to generate bioenergy from food waste.


Asunto(s)
Fuentes de Energía Bioeléctrica , Eliminación de Residuos , Frutas , Anaerobiosis , Residuos Sólidos , Electricidad , Electrodos
10.
Toxins (Basel) ; 15(4)2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-37104186

RESUMEN

Small grain cereals are frequently infected with mycotoxigenic Fusarium fungi. Oats have a particularly high risk of contamination with type A trichothecene mycotoxins; their glucoside conjugates have also been reported. Agronomy practices, cereal variety and weather conditions have been suggested to play a role in Fusarium infection in oats. The current study investigates concentrations of free and conjugated Fusarium mycotoxins in organic and conventional oats grown in Scotland. In 2019, 33 milling oat samples (12 organic, 21 conventional) were collected from farmers across Scotland, together with sample questionnaires. Samples were analysed for 12 mycotoxins (type A trichothecenes T-2-toxin, HT-2-toxin, diacetoxyscirpenol; type B trichothecenes deoxynivalenol, nivalenol; zearalenone and their respective glucosides) using LC-MS/MS. The prevalence of type A trichothecenes T-2/HT-2 was very high (100% of conventional oats, 83% of organic oats), whereas type B trichothecenes were less prevalent, and zearalenone was rarely found. T-2-glucoside and deoxynivalenol-glucoside were the most prevalent conjugated mycotoxins (36 and 33%), and co-occurrence between type A and B trichothecenes were frequently observed (66% of samples). Organic oats were contaminated at significantly lower average concentrations than conventional oats, whereas the effect of weather parameters were not statistically significant. Our results clearly indicate that free and conjugated T-2- and HT-2-toxins pose a major risk to Scottish oat production and that organic production and crop rotation offer potential mitigation strategies.


Asunto(s)
Fusarium , Micotoxinas , Toxina T-2 , Tricotecenos Tipo B , Zearalenona , Micotoxinas/análisis , Avena/microbiología , Grano Comestible/química , Zearalenona/análisis , Cromatografía Liquida , Contaminación de Alimentos/análisis , Espectrometría de Masas en Tándem , Toxina T-2/análisis , Escocia , Glucósidos
11.
Perspect Psychol Sci ; 18(2): 513-526, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36173751

RESUMEN

The extent of the deleterious effects of the COVID-19 pandemic on mental health is recognized ubiquitously. However, these effects are subject to many modulatory factors from a plethora of domains of examination. It is important to understand the intersection of societal and individual levels for global stressors compared with local phenomena and physical-health outcomes. Here, we consider three perspectives: international/cultural, social, and individual. Both the enduring threat of COVID-19 infection and the protective measures to contain contagion have important consequences on individual mental health. These consequences, together with possible remedial interventions, are the focus of this article. We hope this work will stimulate more research and will suggest factors that need to be considered in the coordination of responses to a global threat, allowing for better preparation in the future.


Asunto(s)
COVID-19 , Salud Mental , Pandemias , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/psicología , Salud Mental/estadística & datos numéricos , Pandemias/prevención & control , Salud Global/estadística & datos numéricos , Masculino , Femenino , Distanciamiento Físico , Factores Socioeconómicos , Determinantes Sociales de la Salud
12.
Trials ; 24(1): 83, 2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36747248

RESUMEN

BACKGROUND: In paediatric epilepsy, the evidence of effectiveness of antiseizure treatment is inconclusive for some types of epilepsy. As with other paediatric clinical trials, researchers undertaking paediatric epilepsy clinical trials face a range of challenges that may compromise external validity MAIN BODY: In this paper, we critically reflect upon the factors which impacted recruitment to the pilot phase of a phase IV unblinded, randomised controlled 3×2 factorial trial examining the effectiveness of two antiseizure medications (ASMs) and a sleep behaviour intervention in children with Rolandic epilepsy. We consider the processes established to support recruitment, public and patient involvement and engagement (PPIE), site induction, our oversight of recruitment targets and figures, and the actions we took to help us understand why we failed to recruit sufficient children to continue to the substantive trial phase. The key lessons learned were about parent preference, children's involvement and collaboration in decision-making, potential and alternative trial designs, and elicitation of stated preferences pre-trial design. Despite pre-funding PPIE during the trial design phase, we failed to anticipate the scale of parental treatment preference for or against antiseizure medication (ASMs) and consequent unwillingness to be randomised. Future studies should ensure more detailed and in-depth consultation to ascertain parent and/or patient preferences. More intense engagement with parents and children exploring their ideas about treatment preferences could, perhaps, have helped predict some recruitment issues. Infrequent seizures or screening children close to natural remission were possible explanations for non-consent. It is possible some clinicians were unintentionally unable to convey clinical equipoise influencing parental decision against participation. We wanted children to be involved in decisions about trial participation. However, despite having tailored written and video information to explain the trial to children we do not know whether these materials were viewed in each consent conversation or how much input children had towards parents' decisions to participate. Novel methods such as parent/patient preference trials and/or discrete choice experiments may be the way forward. CONCLUSION: The importance of diligent consultation, the consideration of novel methods such as parent/patient preference trials and/or discrete choice experiments in studies examining the effectiveness of ASMs versus no-ASMs cannot be overemphasised even in the presence of widespread clinician equipoise.


Asunto(s)
Epilepsia , Participación del Paciente , Humanos , Niño , Prioridad del Paciente , Padres , Comunicación , Epilepsia/diagnóstico , Epilepsia/tratamiento farmacológico
13.
BMJ Open ; 13(3): e065769, 2023 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-36898757

RESUMEN

INTRODUCTION: Sleep and epilepsy have an established bidirectional relationship yet only one randomised controlled clinical trial has assessed the effectiveness of behavioural sleep interventions for children with epilepsy. The intervention was successful, but was delivered via face-to-face educational sessions with parents, which are costly and non-scalable to population level. The Changing Agendas on Sleep, Treatment and Learning in Epilepsy (CASTLE) Sleep-E trial addresses this problem by comparing clinical and cost-effectiveness in children with Rolandic epilepsy between standard care (SC) and SC augmented with a novel, tailored parent-led CASTLE Online Sleep Intervention (COSI) that incorporates evidence-based behavioural components. METHODS AND ANALYSES: CASTLE Sleep-E is a UK-based, multicentre, open-label, active concurrent control, randomised, parallel-group, pragmatic superiority trial. A total of 110 children with Rolandic epilepsy will be recruited in outpatient clinics and allocated 1:1 to SC or SC augmented with COSI (SC+COSI). Primary clinical outcome is parent-reported sleep problem score (Children's Sleep Habits Questionnaire). Primary health economic outcome is the incremental cost-effectiveness ratio (National Health Service and Personal Social Services perspective, Child Health Utility 9D Instrument). Parents and children (≥7 years) can opt into qualitative interviews and activities to share their experiences and perceptions of trial participation and managing sleep with Rolandic epilepsy. ETHICS AND DISSEMINATION: The CASTLE Sleep-E protocol was approved by the Health Research Authority East Midlands (HRA)-Nottingham 1 Research Ethics Committee (reference: 21/EM/0205). Trial results will be disseminated to scientific audiences, families, professional groups, managers, commissioners and policymakers. Pseudo-anonymised individual patient data will be made available after dissemination on reasonable request. TRIAL REGISTRATION NUMBER: ISRCTN13202325.


Asunto(s)
Epilepsia Rolándica , Medicina Estatal , Humanos , Niño , Terapia Conductista/métodos , Aprendizaje , Sueño , Análisis Costo-Beneficio , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
14.
Community Pract ; 85(2): 27-31, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22439447

RESUMEN

Behavioural difficulties in the early years and through primary school age present a challenge to community practitioners; and the long-term costs to society of untreated conduct disorder place a huge financial strain on services, as well as leading to a poor prognosis for the children affected. The aim of this study was to establish the long-term effects for participants attending a 12-week Basic Incredible Years Programme, two years post-completion. Fifty-seven participants were interviewed, representing 63% of the original sample, who parented children aged 1-12 years. Pre- and post-intervention and follow-up measures were the General Health Questionnaire (30) and Eyberg Child Behaviour Checklist. The most common theme reported was that it had helped to change their child's behaviour, and this was demonstrated quantitatively with mean average scores for the Eyberg Child Behaviour Inventory reducing to below clinical cut-off post-group and at two years. This same pattern was seen for participants' mental health, with improvements largely maintained at two years. Of the one-third of the children whose behaviour deteriorated two years after the course, two-thirds of these children had experienced adverse life events or had a secondary diagnosis.


Asunto(s)
Trastornos de la Conducta Infantil/prevención & control , Servicios de Salud Comunitaria/organización & administración , Responsabilidad Parental , Lista de Verificación , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Evaluación de Programas y Proyectos de Salud , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios
15.
Chemosphere ; 307(Pt 1): 135709, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35843431

RESUMEN

Microbial fuel cells (MFCs) have the capability of simultaneous sewage treatment and electricity generation. Modifying the cathode electrode enhances their efficiency. In this study, NiTiO3 and CuNiTiO3 were synthesized for practical application as cathode catalysts in a dual-chamber MFC and the performance of the modified cathodes was evaluated against a bare graphite electrode. SEM images showed that the particle sizes were mostly in the range of 40-120 and 20-80 nm for NiTiO3 and CuNiTiO3, respectively. According to AFM results, CuNiTiO3 presented a higher surface roughness than NiTiO3. MFC using CuNiTiO3/G electrode with a reduction potential value of -0.27 V (vs. SCE) and a power density of 62.18 mW m-2 showed better oxygen reduction reaction (ORR) activity compared with NiTiO3/G and the bare graphite. MFC using CuNiTiO3 cathode also showed the highest values in terms of chemical oxygen demand (COD) removal (75%) and the calculated coulombic efficiency (CE, 10%). The results obtained in this study, introduce CuNiTiO3 as a promising electrocatalyst for further improvement of the cathodic reactions in MFC applications.


Asunto(s)
Fuentes de Energía Bioeléctrica , Grafito , Electricidad , Electrodos , Oxígeno , Aguas del Alcantarillado
16.
J Immunol ; 181(6): 3994-4003, 2008 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-18768854

RESUMEN

Genetic mutations disrupting the function of signaling lymphocytic activation molecule-associated protein (SAP) lead to T cell intrinsic defects in T cell-dependent Ab responses. To better understand how SAP enables Th cells to help B cells, we first assessed whether molecules important for B cell help are dysregulated in SAP-deficient (SAP knockout (KO)) mice. CD40 ligand (CD40L) expression was enhanced on unpolarized SAP KO T cells; however, Th2 polarization returned their CD40L expression to wild-type levels without rescuing their ability to help B cells. CD40L also localized normally to the site of contact between SAP KO T cells and Ag-bearing B cells. Finally, CD40L-deficient Th cells and SAP KO Th cells differed in their abilities to help B cells in vitro. These data argue that Ab defects caused by SAP deficiency do not result from a loss of CD40L regulation or CD40L function on CD4 T cells. SAP KO Th cells additionally displayed normal patterns of migration and expression of ICOS and CXCR5. Global gene expression was remarkably similar in activated SAP KO vs wild-type T cells, prompting us to investigate whether SAP is necessary for "programming" T cells to become B cell helpers. By restricting SAP expression during differentiation, we determined that SAP is not required during the first 5 days of T cell activation/differentiation to generate Th cells capable of helping B cells. Instead, SAP is necessary for very late stages of differentiation or, most likely, for allowing Th cells to communicate during cognate T:B interactions.


Asunto(s)
Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Ligando de CD40/fisiología , Comunicación Celular/inmunología , Péptidos y Proteínas de Señalización Intracelular/fisiología , Cooperación Linfocítica/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Ligando de CD40/deficiencia , Ligando de CD40/genética , Comunicación Celular/genética , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Células Cultivadas , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Péptidos y Proteínas de Señalización Intracelular/genética , Cooperación Linfocítica/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Mutantes , Ratones Transgénicos , Transducción de Señal/genética , Transducción de Señal/inmunología , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria , Linfocitos T Colaboradores-Inductores/citología
17.
Environ Technol ; 31(8-9): 1025-43, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20662390

RESUMEN

Large volumes of saline (> 2% w/v NaCl) wastewaters are discharged from many industries; e.g. seafood processing, textile dyeing, oil and gas production, tanneries and drinking water treatment processes. Although anaerobic treatment would be the most cost-effective and sustainable technology for the treatment of many of these saline wastewaters, the salinity is considered to be inhibitory to anaerobic biological treatment processes. The recent applications of salt-tolerant cultures for the treatment of wastewaters from seafood processing and ion-exchange processes suggest that biological systems can be used to treat salty wastewaters. Additionally, organisms capable of anaerobic degradation of contaminants in saline solutions have been observed in marine sediments and have been characterized during the last two decades. This manuscript provides a review of the recent research on anaerobic treatment of saline wastewater and bacterial consortia capable of the anaerobic degradation of pollutants in saline solutions, documenting that the biological treatment of saline wastewaters is promising.


Asunto(s)
Bacterias Anaerobias/metabolismo , Biodegradación Ambiental , Cloruro de Sodio/metabolismo , Contaminantes Químicos del Agua/metabolismo , Residuos Industriales
18.
Community Pract ; 83(10): 27-30, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21049753

RESUMEN

Parents of young children often seek the support of professionals when experiencing difficulties in managing their child's behaviour. Parents of children with complex neurodevelopmental disorders, including autism spectrum disorder (ASD), are no exception. This paper describes a pilot Incredible Years parenting programme that was offered to a group of parents of children with ASD. A service evaluation suggested positive changes within a 12-week period, particularly in parental mental health, but also in child behaviour.


Asunto(s)
Actitud Frente a la Salud , Trastornos Generalizados del Desarrollo Infantil/prevención & control , Educación en Salud/organización & administración , Responsabilidad Parental , Padres , Niño , Trastornos Generalizados del Desarrollo Infantil/psicología , Retroalimentación Psicológica , Humanos , Investigación en Evaluación de Enfermería , Investigación Metodológica en Enfermería , Responsabilidad Parental/psicología , Padres/educación , Padres/psicología , Proyectos Piloto , Evaluación de Programas y Proyectos de Salud , Investigación Cualitativa , Gales
19.
Mater Sci Eng C Mater Biol Appl ; 111: 110754, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32279821

RESUMEN

Over the past decades, inorganic nanoparticles (NPs), particularly metal oxide NPs, have attracted great attention due to their strong bactericidal effects. Researchers have used NPs to fabricate nanocomposite materials which have innate antibacterial capability. Herein, we present a straightforward method to fabricate antibacterial nanocomposites. Ag, TiO2, and ZnO NPs were dispersed within liquid silicone rubber (LSR) structure in four concentrations. Three different methods were used to evaluate the antibacterial efficiency of the NPs forming the nanocomposite materials: (I) the diffusion method, (II) agar counting plate, and (III) a live/dead assay of E. coli. The mechanical properties and hydrophobicity of the nanocomposites were characterized and correlated to the antibacterial efficiency of the NPs. In order to test the antibacterial efficiency in a high-throughput, cost-effective and efficient manner, a microfluidic device fabricated by 3D printing and soft-lithography methods was used. The LSR-15 wt% TiO2 nanocomposites showed the best antibacterial efficiency. In addition, TiO2 NPs formed the stiffest nanocomposites with very fine, even surface which increased the hydrophobicity of the surface where bacteria attach to grow, preventing bacteria from further growth.


Asunto(s)
Antibacterianos/química , Dispositivos Laboratorio en un Chip , Nanocompuestos/química , Polímeros/química , Antibacterianos/farmacología , Pruebas Antimicrobianas de Difusión por Disco , Escherichia coli/efectos de los fármacos , Nanopartículas del Metal/química , Nanocompuestos/toxicidad , Plata/química , Titanio/química , Óxido de Zinc/química
20.
IEEE Trans Biomed Circuits Syst ; 14(1): 2-11, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31715571

RESUMEN

Microwave resonator sensors are attractive for their contactless and label-free capability of monitoring bacterial growth in liquid media. This paper outlines a new label-free microwave biosensor based on a pair of planar split ring resonators for non-invasive monitoring of bacterial growth on a solid agar media. The sensor is comprised of two split ring resonators with slightly different resonant frequencies for differential operation. The transmission coefficient (S21) of the sensor is considered as the sensor's response with a designed and measured quality factor above 200 to ensure a high-resolution operation of the biosensor. Two resonant frequencies of 1.95 and 2.11 GHz represent the sensing signal and the reference signal, respectively. The developed sensor demonstrates high performance in monitoring the growth dynamics of Escherichia coli (E. coli) on Luria-Bertani (LB) agar with 4 mm thickness. The sensor's resonant amplitude response demonstrated 0.5 dB variation corresponding to the bacterial growth over 48 hours when bacteria were spread on LB agar starting with initial OD600 = 1.5. Moreover, 0.6 dB change in the sensor's response was observed over 96 hours of bacterial growth starting with an initial OD600 = 1.17 spotted on LB agar. The measured results fit well to the curves created using Richards' bacterial growth model, showing the strength of the sensor as a potential candidate for use in predictive food microbiology systems.


Asunto(s)
Técnicas Biosensibles/instrumentación , Medios de Cultivo/química , Escherichia coli/crecimiento & desarrollo , Carga Bacteriana , Diseño de Equipo , Microondas
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