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Corrosion Behaviour of 2A97-T8 Al-Cu-Li Alloy Extrusion
No full textIn the present study, correlative corrosion testing and electron microscopy, including quasi-in-situ electron microscopy, are employed to investigate the corrosion behaviour of 2A97-T8 Al-Cu-Li alloy extrusion in 3.5 wt. % NaCl solution. It is found that the corrosion behaviour of the alloy is influenced by synergetic effect of the plastic deformation introduced by the thermomechanical processing during alloy fabrication and the precipitation of T1 phase during T8 treatment. Localized corrosion initiates and propagates preferentially within non-recrystallized regions of the partially recrystallized alloy. Corrosion initiated at coarse constituent intermetallic particles is confined to its periphery, which doesn’t develop further when the particles are disconnected from alloy matrix
Loneliness in young people: A multilevel exploration of social ecological influences and geographic variation.
No full textBackground: Loneliness is a growing public health concern, yet little is known about loneliness in young people. The current study aimed to identify social ecological factors related to loneliness and examine the extent to which geographic region may account for differences in loneliness.Methods: The data come from a cross-sectional sample of 6503 young people living in the United Kingdom. Loneliness was measured using the UCLA 3-item scale. Bivariate analyses were used to test associations between each predictor and loneliness. Multilevel models were used to identify key social ecological factors related to loneliness, and the extent to which loneliness may vary across geographic regions (Local Authority districts). Results: Socio-demographic, social, health and wellbeing, and community factors were found to be associated with loneliness. Geographic region was associated with 5-8% of the variation in loneliness. The effect of gender, sexual orientation, and minority ethnic background on loneliness differed across regions.Conclusions: This is the first study to highlight modifiable social and community factors related to youth loneliness, and individual vulnerabilities, such as poor mental wellbeing.Results related to geographic differences suggest that local-level initiatives may be most appropriate in tackling loneliness, rather than wider, less contextualized national efforts
Integrating techno-economic, environmental and safety criteria in solvent screening for extraction processes: The case of algae lipid extraction
No full textVolatile organic solvents derived from fossil resources are typically used in extraction processes, but this usually involves high energy consumption for solvent recovery and negative environmental impacts due to solvents’ hazardous, volatile, and flammable nature. This study presents a systematic approach to solvent screening, using molecular and process simulation techniques, data analysis and classification methods applying techno-economic, environmental and safety criteria. This methodology is demonstrated for lipid extraction from wet algae biomass in biofuel production. First, relevant thermodynamic equilibrium data are predicted with the COSMO-RS (Conductor-like Screening Model for Real Solvents) method. The resulting solvents are clustered according to their partition coefficient and selectivity towards the target solute, and screened further, considering their physicochemical properties and health, safety and environmental (HSE) performance. Finally, the lipid extraction process is simulated in Aspen Plus using all screened solvents to obtain technical, economic, and environmental performance data. Out of 88 initial candidates, cyclohexane, limonene, and ethyl tert-butyl ether are identified as potential alternatives to the benchmark solvent, hexane. Whilst these solvents tend to be more expensive and their recovery more energy intensive (higher boiling points) compared to hexane, they have higher selectivity towards lipids thus reducing the solvent intensity of the process, and are less volatile and non-hazardous according to the HSE classification. This methodology can be applied to other extraction process applications or implemented at early stages in process design to evaluate techno-economic, environmental and safety trade-offs when considering and selecting more sustainable alternatives to fossil-derived solvents. Keywords: COSMO-RS, process simulation, green solvents, biodiesel, sustainability indicators.<br/
Joint Altitude and Hybrid Beamspace PrecodingOptimization for UAV-enabled Multiuser mmWave MIMO System
No full textThe combination of unmanned aerial vehicles (UAVs) and millimeter wave (mmWave) multiple-input multipleout (MIMO) system is regarded as a key enabling technology for beyond 5G networks, as it provides high data rate aerial links. However, establishing UAV-enabled mmWave MIMO communication is quite challenging due to the high hardware cost in terms of radio frequency (RF) chains. As a cost-effective alternative, a beamspace precoding with discrete lens arrays (DLA) architecture has received considerable attention. However, the underlying optimal design in beamspace precoding has not been fully exploited in UAV-enabled communication scenario. In this paper, the joint design of the UAV’s altitude and hybrid beamspace precoding is proposed for the UAV-enabledmultiuser MIMO system, in which the DLA is exploited to reduce the number of the RF chain. In the proposed scheme, the optimization problem is formulated as a minimum weighted mean squared error (MWMSE) method. Then an efficient algorithm with the penalty dual decomposition (PDD) is proposed that aimsto jointly optimize the altitude of UAV, beam selection and digital precoding matrices. Simulation results confirm the comparable performance of the proposed scheme and perform close to fulldigital beamforming in terms of achievable spectral efficiency.Index Terms—UAV, mmWave communication, MIMO, hybri
Sequential Chemotherapy-Radiotherapy as Adjuvant Treatment of High-Risk Endometrial Carcinoma: the Manchester Experience
No full textApproximately 15% of women with endometrial cancer present with high-risk disease which increases the risk of progression and death. The optimal adjuvant treatment of high-risk endometrial cancer after primary debulking surgery remains incompletely defined. Here we report the outcomes of such patients treating with sequential chemotherapy-radiotherapy at a large cancer centre in Manchester, UK.A retrospective analysis was carried out of 111 consecutive patients referred for adjuvant treatment of high-risk endometrial cancer in 2014 and 2015. High-risk patients were defined as those with FIGO 2009 stage I grade 3 endometrioid carcinoma with deep myometrial invasion and/or LVSI, stage II-III endometrioid carcinoma, or any other high-risk histological subtype with stage I-III disease. Patients were followed up for a median of 67 months to measure recurrence free survival (RFS) and overall survival (OS), as well as treatment-related toxicity.Patients had a mean age of 67 years (range 33-82), a median body mass index (BMI) of 29.1 (range 16.3-59); the majority had endometrioid histology (48%). Seventy-six percent of patients were treated with sequential chemotherapy-radiotherapy; the reason for receiving single modality adjuvant therapy was mainly patient choice or contra-indications to treatment. Patients who received sequential chemotherapy-radiotherapy had a 5-year RFS of 70% (95% CI 60.8-80.6%) and a 5-year OS of 71.4% (95% CI 62.3-81.7%). Patients tolerated treatment well with 96% of patients completing planned sequential chemotherapy-radiotherapy treatment, and only 18% of patients had grade 3 or above adverse events.Sequential chemotherapy-radiotherapy as adjuvant treatment for high-risk endometrial cancer was associated with good progression free and overall survival outcomes, consistent with the results of recent phase III clinical trials. Further research is needed to determine the impact of molecular subgroups on prognosis and efficacy of adjuvant therapy.<br/
Feasibility of a multiparametric MRI protocol for imaging biomarkers associated with neoadjuvant radiotherapy for soft tissue sarcoma
No full textObjectivesSoft tissue sarcoma (STS) is a rare malignancy with a 5 year overall survival rate of 55%. Neoadjuvant radiotherapy is commonly used in preparation for surgery, but methods to assess early response are lacking despite pathological response at surgery being predictive of overall survival, local recurrence and distant metastasis. Multiparametric MR imaging (mpMRI) is used to assess response in a variety of tumours but lacks a robust, standardised method. The overall aim of this study was to develop a feasible imaging protocol to identify imaging biomarkers for further investigation.MethodsFifteen patients with biopsy-confirmed STS suitable for preoperative radiotherapy and radical surgery were imaged throughout treatment. The mpMRI protocol included anatomical, diffusion weighted and dynamic contrast-enhanced imaging, giving estimates of apparent diffusion coefficient (ADC) and the area under the enhancement curve at 60 s (iAUC60). Histological analysis of resected tumours included detection of CD31, Ki67, HIF and calculation of a hypoxia score.ResultsThere was a significant reduction in T1 at visit 2 and in ADC at visit 3. Significant associations were found between hypoxia and pre-treatment iAUC60, pre-treatment ADC and mid-treatment iAUC60. There was also statistically significant association between mid-treatment ADC and Ki67. ConclusionsThis work showed that mpMRI throughout treatment is feasible in patients with STS having neoadjuvant radiotherapy. The relationships between imaging parameters, tissue biomarkers and clinical outcomes warrant further investigation.Advances in KnowledgempMRI based biomarkers have good correlation with STS tumour biology and are potentially of use for evaluation of radiotherapy response.<br/
Mood monitoring in bipolar disorder: Is it always helpful?
No full textThis article offers a cautionary note about the use of mood monitoring in bipolar disorder. We propose that, although potentially helpful for some individuals, mood monitoring in bipolar disorder can at times be inappropriate and even harmful. We finish by offering tentative recommendations for future practice.Learning points: - There is cautionary evidence to suggest that mood monitoring is unhelpful for some people with a diagnosis of bipolar disorder. - We tentatively suggest that an individualised, collaborative and normalising approach to mood monitoring may be optimal and reduce potential limitations. <br/
Multi-objective Workforce Allocation in Construction Projects
No full textManaging construction projects is a complex, resource-intense and risky task that involves the organization and management of people skilled in the design and completion of construction projects. Embarking on a construction project means to plan the allocation of resources and labour, while ensuring that the output (e.g. a new building) meets a certain quality, and is delivered in time and within budget without breaching contractual obligations. We formulate a simplified version of this task as a constrained multi-objective optimization problem, and then use a non-dominated sorting genetic algorithm to tackle the problem. In addition to providing a formal definition of the problem, further contributions of this work include the validation of the methodology using real data of construction projects varying in scale and resource-utilisation; the use of real data is scarce in the construction project management area. We also perform a scenario-based analysis to understand how the approach reacts to changing environmental parameters (such as availability of resources). Finally, we discuss practical implications. Our empirical analysis highlights that the proposed approach improves significantly in terms of project budget, quality, and duration targets, when compared with the industry standard.</p
Low-pass genome sequencing-based detection of absence of heterozygosity: validation in clinical cytogenetics
No full textPurpose: Absence of heterozygosity (AOH) is a genetic characteristic known to cause human genetic disorders through autosomal recessive or imprinting mechanisms. However, the analysis of AOH via low-pass genome sequencing (GS) is yet to be clinically available.Methods: Low-pass GS (4-fold) with different types of libraries was performed on 17 clinical samples with previously ascertained AOH by chromosomal microarray analysis (CMA). In addition, AOH detection was performed with low-pass GS data in 1,639 cases that had both GS and high-probe-density CMA data available from the 1000 Genomes Project. Cases with multiple AOHs (coefficient of inbreeding F ≥1/32) or terminal AOHs ≥5-Mb (suspected uniparental disomy) were reported based on guidelines of the American College of Medical Genetics and Genomics.Results: Low-pass GS revealed suspected segmental UPD and multiple AOHs (F≥1/32) in nine and eight clinical cases, respectively, consistent with CMA. Among the 1,639 samples, low-pass GS not only consistently detected multiple AOHs (F≥1/32) in 18 cases, but also reported 60 terminal AOHs in 44 cases including four mosaic AOHs at a level ranging from 50% to 75%.Conclusion: Overall, our study demonstrates the feasibility of AOH analysis (≥5-Mb) with low-pass GS data and shows high concordance compared with CMA.<br/