110 research outputs found
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Highly efficient separation of actinides from lanthanides by a phenanthroline-derived bis-triazine ligand
The synthesis, lanthanide complexation, and solvent ex- traction of actinide(III) and lanthanide(III) radiotracers from nitric acid solutions by a phenanthroline-derived quadridentate bis-triazine ligand are described. The ligand separates Am(III) and Cm(III) from the lanthanides with remarkably high efficiency, high selectivity, and fast extraction kinetics compared to its 2,2'-bipyridine counterpart. Structures of the 1:2 bis-complexes of the ligand with Eu(III) and Yb(III) were elucidated by X-ray crystallography and force field calculations, respec-tively. The Eu(III) bis-complex is the first 1:2 bis-complex of a quadridentate bis-triazine ligand to be characterized by crystallography. The faster rates of extraction were verified by kinetics measurements using the rotating membrane cell technique in several diluents. The improved kinetics of metal ion extraction are related to the higher surface activity of the ligand at the phase interface. The improvement in the ligand's properties on replacing the bipyridine unit with a phenanthroline unit far exceeds what was anticipated based on ligand design alone
Multimodality Treatment with Conventional Transcatheter Arterial Chemoembolization and Radiofrequency Ablation for Unresectable Hepatocellular Carcinoma
Background/Aims: To evaluate the efficacy of multimodality treatment consisting of conventional transcatheter arterial chemoembolization (TACE) and radiofrequency ablation (RFA) in patients with non-resectable and non-ablatable hepatocellular carcinoma (HCC). Methods: In this retrospective study, 85 consecutive patients with HCC (59 solitary, 29 multifocal HCC) received TACE followed by RFA between 2001 and 2010. The mean number of tumors per patient was 1.6 +/- 0.7 with a mean size of 3.0 +/- 0.9 cm. Both local efficacy and patient survival were evaluated. Results: Of 120 treated HCCs, 99 (82.5%) showed a complete response (CR), while in 21 HCCs (17.5%) a partial response was depicted. Patients with solitary HCC revealed CR in 91% (51/56); in patients with multifocal HCC (n = 29) CR was achieved in 75% (48 of 64 HCCs). The median survival for all patients was 25.5 months. The 1-, 2-, 3- and 5-year survival rates were 84.6, 58.7, 37.6 and 14.6%, respectively. Statistical analysis revealed a significant difference in survival between Barcelona Clinic Liver Cancer (BCLC) A (73.4 months) and B (50.3 months) patients, while analyses failed to show a difference for Child-Pugh score, Cancer of Liver Italian Program (CLIP) score and tumor distribution pattern. Conclusion: TACE combined with RFA provides an effective treatment approach with high local tumor control rates and promising survival data, especially for BCLC A patients. Randomized trials are needed to compare this multimodality approach with a single modality approach for early-stage HCC. Copyright (C) 2011 S. Karger AG, Base
Preliminary results of intracranial aneurysm treatment with derivo2heal embolization device
Introduction
The Derivo 2 Heal Embolization Device (D2HED) is a novel flow diverter (FD) providing a fibrin-/heparin-based surface coating aiming at lower thrombogenicity. We evaluate periprocedural aspects and preliminary aneurysm occlusion efficacy for intracranial aneurysm treatment.
Methods
Thirty-four D2HEDs deployments (34 aneurysms, 32 patients) between 04/2021 and 10/2023 were analyzed. All patients were under dual antiplatelet therapy (dAPT). Periprocedural details, adverse events, and follow-up (FU) imaging were reviewed by consultant-level neuroradiologists. Complication rates and aneurysm occlusion efficacy are compared with performance data of other FDs based on literature research.
Results
Each intervention succeeded in the deployment of one D2HED. Significant and/or increased intraaneurysmal contrast stagnation immediately after D2HED deployment was seen in 73.5% of cases according to O’Kelly-Marotta (OKM) grading scale. Clinically relevant early adverse events occurred in three patients: Among them two cases with fusiform aneurysms in the posterior circulation (ischemic events, early in-stent-thrombosis) and one patient (ischemic event) out of the majority of 31 treated internal carotid artery aneurysms (3,2%). Regarding mid-term FU (> 165 days), one aneurysm did not show progressive occlusion presumably caused by a prominent A1 segment arising from the terminal ICA aneurysm itself. Apart from that, mid-term complete / partial occlusion rates of 80% / 20% could be demonstrated.
Conclusion
Our case series - although suffering from restricted sample size - suggests a potential effectiveness of D2HED in managing intracranial aneurysms. Further studies with larger samples are warranted to quantify long-term occlusion efficacy and the impact of antithrombogenic surface coating on the necessary (d)APT
Biomass Ashes for Acid Mine Drainage Remediation
Acid mine drainage (AMD) is the largest environmental problem facing the world mining and processing industry because it has low pH and can contain high concentrations of potential pollutants. Biomass ash (BA) can be considered as a potential material for AMD treatment. The main goal of this work was to investigate potential use of Biomass ash of CPK-LA and PK-LA types for AMD remediation. Four UK BAs from different fuels (i.e. straw, meat and bone meal, poultry litter), synthetic AMD, and raw AMDs (Belovo and Ursk) were used for the AMD treatment experiments. Batch experiments showed that in 1 h the biomass ash from straw combustion can effectively neutralise the synthetic AMD and the Belovo AMD with removal of potential pollutants at the liquid-to-solid ratio (L/S) of 100–250 and 10–50, respectively. The biomass ashes from straw and poultry litter combustion can effectively remove pollutants from the Ursk AMD at L/S 100 and adjust pH. The metal concentrations of those treated AMDs met receiving water quality standards. Potential pollutants precipitated as carbonate/hydroxide/sulphate, co-precipitated with Fe oxyhydroxides and Ca phosphates, and appeared as new phases such as Ca, Cu, Zn phosphates and Ca, Fe phosphates. This investigation is essential for development of appropriate, environmentally friendly and economically rational waste management
What Does It Take to Make it to the Polling Station? The Effects of Campaign Activities on Electoral Participation
This study explores the extent to which campaign visibility facilitates electoral participation, using data from first- and second-order elections in Britain. Our contribution to the existing literature is threefold. First, we assess whether the effects of campaign effort are conditioned by marginality, finding that campaign mobilisation gets out the vote regardless of the competitiveness of the race. Second, we look at the relative ability of different campaign activities to stimulate turnout, detecting significant differences. Third, we show that the effects of campaign effort on electoral participation are rather similar in first- and second-order elections. These findings suggest that a greater level of electoral information provided by campaign activities does reduce the costs of voting. Local campaigns play a key role in bringing voters to the polls in marginal and non-marginal races, and at general elections as much as at second-order elections
Percutaneous ct fluoroscopy-guided core needle biopsy of mediastinal masses: Technical outcome and complications of 155 procedures during a 10-year period
Purpose: To evaluate technical outcome, diagnostic yield and safety of computed tomo-graphic fluoroscopy-guided percutaneous core needle biopsies in patients with mediastinal masses. Methods: Overall, 155 CT fluoroscopy-guided mediastinal core needle biopsies, performed from March 2010 to June 2020 were included. Size of lesion, size of needle, access path, number of success, number of biopsies per session, diagnostic yield, patient’s position, effective dose, rate of complications, tumor localization, size of tumor and histopathological diagnosis were considered. Post-interventional CT was performed, and patients observed for any complications. Complications were classified per the Society of Interventional Radiology (SIR). Results: 148 patients (age, 54.7 ± 18.2) underwent 155 CT-fluoroscopy-guided percutaneous biopsies with tumors in the anterior (114; 73.5%), middle (17; 11%) and posterior (24; 15.5%) mediastinum, of which 152 (98%) were technically successful. For placement of the biopsy needle, in 82 (52.9%) procedures a parasternal trajectory was chosen, in 36 (23.3%) a paravertebral access, in 20 (12.9%) through the lateral intercostal space and in 17 (11%) the thoracic anterior midline, respectively. A total of 136 (89.5%) of the biopsies were considered adequate for a specific histopathologic analysis. Total DLP (dose-length product) was 575.7 ± 488.8 mGy*cm. Mean lesion size was 6.0 ± 3.3 cm. Neoplastic pathology was diagnosed in 115 (75.7%) biopsies and 35 (23%) biopsy samples showed no evidence of malignancy. Minor complications were observed in 18 (11.6%) procedures and major pneumothorax requiring drainage insertion in 3 interventions (1.9%). Conclusion: CT fluoroscopy-guided percutaneous core needle biopsy of mediastinal masses is an effective and safe procedure for the initial assessment of patients with mediastinal tumors
A Framework for Predicting and Managing Water Quality Impacts of Mining on Streams: A User’s Guide
Coal and gold mining are important economic activities in New Zealand, and the West Coast of the South Island and Southland, for example, have long histories of mining. The process of mineral extraction inevitably results in environmental impacts, but few tools exist to help mining companies and regulators assess and predict environmental impacts of mining operations. This framework has been developed as part of a collaborative research programme with key mining partners to assist with planning of future mine developments on the West Coast and in Southland. This framework focuses on water quality issues associated with coal and gold mining, specifically pH, metals and, to a limited extent, suspended solids. It draws together research on rock geochemistry, aquatic chemistry, freshwater ecology, aquatic toxicity, and management and treatment techniques for mining to provide a process for data collection and decision making. The main body of the document outlines the process, including data required, methods of collection and interpretation of those data. A series of appendices provide the more technical and scientific results that underpin the processes and decision trees used in the document. Specifically, the framework provides information on collection of the water, rock and biological information used to (a) predict water quality prior to mining, (b) monitor discharges from mines, and (c) identify mining-related impacts. In addition, the framework includes information on state-of-the-art techniques for prevention of poor water quality in mine drainages and optimal strategies for management of mine waste or overburden and treatment of
The state of mixed methods research in nursing: a focused mapping review and synthesis
Aims
To consider the scope and quality of mixed methods research in nursing.
Design
Focused mapping review and synthesis (FMRS).
Data sources
Five purposively selected journals: International Journal of Nursing Studies, Journal of Nursing Scholarship, Journal of Advanced Nursing, Worldviews on Evidence-Based Nursing, and Journal of Mixed Methods Research.
Review methods
In the target journals, titles and abstracts from papers published between 2015–2018 were searched for the words or derivative words ‘mixed methods’. Additional keyword searches were undertaken using each journal's search tool. We included studies that investigated nursing and reported to use a mixed methods approach. Articles that met the inclusion criteria were read in full and information was extracted onto a predetermined pro forma. Findings across journals were then synthesized to illustrate the current state of mixed methods research in nursing.
Results
We located 34 articles that reported on mixed methods research, conducted across 18 countries. Articles differed significantly both within and across journals in terms of conformity to a mixed methods approach. We assessed the studies for the quality of their reporting as regard the use of mixed methods. Nineteen studies were rated as satisfactory or good, with 15 rated as poorly described. Primarily, a poor rating was due to the absence of stating an underpinning methodological approach to the study and/or limited detail of a crucial integration phase.
Conclusions
Our FMRS revealed a paucity of published mixed methods research in the journals selected. When they are published, there are limitations in the detail given to the underpinning methodological approach and theoretical explanation
Clinical effectiveness and cost-effectiveness of Structured Psychological Support for people with probable personality disorder in mental health services in England: study protocol for a randomised controlled trial
Introduction
Evidence-based psychological treatments for people with personality disorder usually involve attending group-based sessions over many months. Low-intensity psychological interventions of less than 6 months duration have been developed, but their clinical effectiveness and cost-effectiveness are unclear.
Methods and analysis
This is a multicentre, randomised, parallel-group, researcher-masked, superiority trial. Study participants will be aged 18 and over, have probable personality disorder and be treated by mental health staff in seven centres in England. We will exclude people who are: unwilling or unable to provide written informed consent, have a coexisting organic or psychotic mental disorder, or are already receiving psychological treatment for personality disorder or on a waiting list for such treatment. In the intervention group, participants will be offered up to 10 individual sessions of Structured Psychological Support. In the control group, participants will be offered treatment as usual plus a single session of personalised crisis planning. The primary outcome is social functioning measured over 12 months using total score on the Work and Social Adjustment Scale (WSAS). Secondary outcomes include mental health, suicidal behaviour, health-related quality of life, patient-rated global improvement and satisfaction, and resource use and costs. The primary analysis will compare WSAS scores across the 12-month period using a general linear mixed model adjusting for baseline scores, allocation group and study centre on an intention-to-treat basis. In a parallel process evaluation, we will analyse qualitative data from interviews with study participants, clinical staff and researchers to examine mechanisms of impact and contextual factors.
Ethics and dissemination
The study complies with the Helsinki Declaration II and is approved by the London—Bromley Research Ethics Committee (IRAS ID 315951). Study findings will be published in an open access peer-reviewed journal; and disseminated at national and international conferences.
Trial registration number
ISRCTN13918289
Novel cost effective full scale mussel shell bioreactors for metal removal and acid neutralization
Acid mine drainage (AMD) impacted waters are a worldwide concern for the mining industry and countries dealing with this issue; both active and passive technologies are employed for the treatment of such waters. Mussel shell bioreactors (MSB) represent a passive technology that utilizes waste from the shellfish industry as a novel substrate. The aim of this study is to provide insight into the biogeochemical dynamics of a novel full scale MSB for AMD treatment. A combination of water quality data, targeted geochemical extractions, and metagenomic analyses were used to evaluate MSB performance. The MSB raised the effluent pH from 3.4 to 8.3 while removing up to ~99% of the dissolved Al, and Fe and >90% Ni, Tl, and Zn. A geochemical gradient was observed progressing from oxidized to reduced conditions with depth. The redox conditions helped define the microbial consortium that consists of a specialized niche of organisms that influence elemental cycling (i.e. complex Fe and S cycling). MSB technology represents an economic and effective means of full scale, passive AMD treatment that is an attractive alternative for developing economies due to its low cost and ease of implementation
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