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Electricity-driven synergistic sulfur recovery and sulfate elimination in seawater
No full textHigh sulfate (SO42-) concentration inhibits seawater utilization but provides a potential source for elemental sulfur (S0) production. The aim of this study was to investigate the feasibility of SO42- removal with the enhancement of S0 recovery simultaneously using a biotic-abiotic hybrid electrochemical (BAHE) process. Long-term operation (i.e., ∼ 240 d) of the biotic electrochemical unit (i.e., single-chamber bioelectrochemical system) obtained a low S0 recovery of 0.78 ± 0.08 % with high SO42- removal exceeding 95 %. The non-conductive S0 precipitated on the anodic surface inhibited continuous electrochemical oxidation of S2-, resulting in the S2- accumulation in the effluent of the bioelectrochemical process and low S0 recovery. In contrast, efficient S2- oxidation took place on the anode surface of the abiotic electrochemical process with electricity generation. The final S2- concentration in the BAHE process was much lower than that in the individual bioelectrochemical process (3 ± 1 vs. 539 ± 60 mg/L). Efficient S0 recovery (i.e., 71.73 ± 7.17 %) and SO42- reduction (92 ± 5 %) were realized in the BAHE process, mainly attributed to the synergistic effect between the single-chamber bioelectrochemical and abiotic electrochemical cells. Our results may provide a promising way for both seawater utilization and elemental sulfur production.</p
Investigating the Monumental Fortification Walls of the Vedi Fortress of Armenia through Digital 3D Reconstruction
No full textThe Vedi Fortress protects the entrance to the Vedi River Valley of Armenia along the southeastern edge of the Ararat Plain. Still visible on this site's surface are two lines of monumental fortification walls, together over 400 meters long. First constructed during the Late Bronze Age (LBA; ca 1550-1200 BCE) and reused in the Early Medieval (Late Antique; ca 450-650 CE) period, these fortifications are contributing new information about the emergence of LBA fortress culture in the Southern Caucasus. Several segments of the walls are well preserved, but others have deteriorated to varying degrees over time. This leaves us with many questions about how the walls interacted with the site’s topography, how certain areas of the site were enclosed, and how the walls would have originally appeared to people, including with features such as gates and towers. To address these questions, we combine careful field observation, high resolution 3D photogrammetric scanning by hand and by drone, and the painstaking 3D digital reconstruction of the walls. We are specifically foregrounding 3D modeling as a process for studying architecture given its exacting nature, which forces us to make explicit decisions on how each part of the walls would have looked in the past. This paper presents both our process and our results, the 3D model itself and our enhanced understanding of the site. Through this detailed investigation, we are gaining new perspectives on the purposes, functions, and the underlying community-formation processes that led to the construction of the Vedi Fortress. </p
Economic analysis of parking, vehicle charging and vehicle-to-grid services in the era of electric vehicles
No full textWith the advances in electrical technologies (especially the vehicle-to-grid or V2G technologies), electric vehicles (EVs) now can be used as power storage. The latent power storage capacity in EVs can provide additional flexibility to the power system, and thus helps enhance the overall efficiency, stability and reliability of the power grid. With the V2G facility in place, EV users can choose to share their vehicles to the power grid as temporary storage while the vehicle is being parked or charged (termed as ‘V2G parking or charging service’). This study investigates the pricing and capacity decisions of parking, charging and V2G operators, subject to the EV users’ choice equilibrium. An EV user who demands parking or charging can choose the (conventional) dedicated parking or charging slot (managed by the parking or charging operator) or the slot of V2G facility such that his/her vehicle can be used by the power grid as temporary storage while being parked or charged (managed by the V2G operator). We formulate and analyze the EV user choice equilibrium subject to parking, charging and V2G service provision, and then investigate parking, charging and V2G operators’ optimal service fare and capacity decisions in different market regimes, where the operators may compete or cooperate with each other (e.g., charging and V2G facilities might be operated jointly). The main findings are as follows. (i) Introducing the V2G-based parking/charging service might earn a positive profit for the V2G operator and also benefit customers who request for parking or charging, but the parking and charging operators will suffer a loss. (ii) The competition between operators tends to reduce the service fares, while cooperation tends to increase the fares and yield more profits for the operators. (iii) The optimal capacity of parking, charging, or V2G facilities should be set to balance the marginal capacity acquisition cost and the marginal facility searching time cost. (iv) When V2G operator cooperates with parking/charging operator, if the additional gains of parking/charging operator through cooperation are smaller than that of V2G operator, the optimal service fare of parking/charging should be smaller, and thus will benefit the parkers/chargers (after V2G service is introduced). (v) The collaboration between parking (or charging) and V2G operators might also benefit the charging (or parking) operator. Overall, this study enhances the understanding in relation to parking and charging operators’ reactions to emerging V2G-based parking and charging services, and provides insights regarding how the V2G service should be planned and optimized.</p
ORDER ALLOCATION AND VEHICLE ROUTING PROBLEMS WITH CROWDSOURCED AND PROFESSIONAL COURIERS
No full textThis study investigates the order allocation and vehicle routing problems of an integrated logistics platform with crowdsourced and professional couriers. Specifically, we consider the Pickup and Delivery Problem with Time Windows, Transshipment, and Consolidation (CS-PDPTWTC), where trucks, professional couriers, and crowdsourced carriers (crowd-carriers) collaborate to serve all pickup and delivery requests from intercity and intracity. Trucks consolidate parcels among service points and the distribution center. Professional couriers depart from service points and handle pickup and delivery tasks inside their service region. Meanwhile, crowd-carriers can perform delivery tasks using parcel lockers as transshipment points. In other words, professional couriers can deposit the parcels in lockers for temporary storage, and then crowd-carriers can collect the parcels from lockers and deliver to the final destination. The objective is to minimize the total delivery cost while satisfying all demands by optimizing order allocation and vehicle routing. The CS-PDPTWTC problem is formulated as a Mixed Integer Linear Programming (MILP) model. As the CS-PDPTWTC is NP-hard, we develop an Adaptive Large Neighborhood Search (ALNS) algorithm that significantly improves solving efficiency. Numerical results across different scenarios show that integrating crowdshipping into pickup and delivery services can reduce operational costs, offering substantial economic benefits. Sensitivity analysis further indicates that the operator can reduce the logistics cost by attracting more potential crowd-carriers, reducing their compensation rate, and increasing the number of service points within a certain range.</p
Global differences and risk factors influencing drug hypersensitivity quality of life: A multicenter, multiethnic study of drug allergy across 3 continents
No full textBackground: Penicillin allergy labels are associated with many adverse outcomes. Fear and restriction of future medication use also have an impact on health-related quality of life (HR-QoL). However, the impact of a drug allergy on HR-QoL and its associated factors remains unknown. Objective: We sought to investigate the impact of penicillin allergy labels and compare the factors associated with HR-QoL impairment among patients in an international multicenter, multiethnic cohort. Methods: HR-QoL was measured using the 6-item Drug Hypersensitivity Quality of Life Questionnaire (DrHy-Q) and compared among patients labeled with penicillin allergy, before their allergy evaluation, from 8 adult allergy/immunology clinics across Asia, Australia, and North America. Results: We recruited 643 patients labeled with penicillin allergy (median age, 56 years [interquartile range, 39-67]; male:female ratio, 1:2.2), with 273 (42.5%), 186 (28.9%), and 184 (28.6%) from Asia, North America, and Australia, respectively. The median DrHy-Q score was 8.3 (interquartile range, 0.0-29.2). All patients underwent penicillin allergy evaluation, and 96% (617 of 643) were delabeled following negative provocation test results. Female patients (8.3 vs 4.2; P = .003), those with other concomitant antimicrobial allergy labels (20.8 vs 4.2; P = .004), and patients from Asia (33.3 vs 4.2 [North America] vs 0 [Australia]; P < .001) had significantly higher DrHy-Q scores, reflecting a reduced HR-QoL. Ethnicity as well as other allergy variables were not significant in the multivariate analysis. Conclusions: Regional differences, ethnicity, and other risk factors influence HR-QoL impairment among patients labeled with penicillin allergy. Future studies are needed to understand the contributions of regional sociodemographic factors and identify interventions to improve HR-QoL.</p
Aspirin is associated with lower risk of pancreatic cancer and cancer-related mortality in patients with diabetes mellitus
No full textBackground: Patients with type 2 diabetes mellitus (T2DM) have higher pancreatic cancer (PC) risk. While aspirin has chemopreventive effects on digestive cancers, its effect on PC among patients with T2DM is unclear.Methods: This retrospective cohort study identified newly diagnosed adult patients with T2DM in Hong Kong between 2001 and 2015 from a territory-wide healthcare registry. Exclusion criteria were history of PC, pancreatic cyst, IgG4 disease, or pancreatectomy. To address reverse causality between PC and T2DM, we excluded patients with PC diagnosed within 1 year of T2DM. We also excluded patients with less than 1 year of observation. Primary outcome was PC, and secondary outcomes were PC-related and all-cause mortality. Aspirin use was treated as time-varying variable (≥180 day-use/year) to address immortal-time bias, and multivariable Cox regression model was employed to derive adjusted HR (aHR). Propensity-score (PS) matching was used as secondary analysis.Results: Among 343 966 newly diagnosed patients with T2DM (median follow-up: 10.5 years; IQR: 7.7-14.5 years), 1224 (0.36%) developed PC. There were 51 151 (14.9%) deaths from any cause, and 787 (0.2%) died from PC. Aspirin use was associated with lower PC risk in both time-dependent (aHR: 0.58; 95% CI 0.49 to 0.69) and PS matching analysis (aHR: 0.61; 95% CI 0.48 to 0.77). An inverse relationship was observed with increasing dose and duration of aspirin use (P trendConclusion: Aspirin use may be an oncopreventive strategy to reduce PC risk in patients with T2DM. Further studies are warranted to validate the study findings.</p
Risk of mortality and complications in people with depressive disorder and diabetes mellitus: A 20-year population-based propensity score-matched cohort study
No full textPeople with depression have increased premature mortality and elevated prevalence of diabetes-mellitus compared to general population. However, risk of mortality and diabetes-related complications among patients with depression and co-occurring diabetes is under-studied. This population-based propensity score-matched (1:10) cohort study identified 12,175 patients with pre-existing depression and incident-diabetes (depression-diabetes group) and 117,958 patients with incident-diabetes only (diabetes-only group) between 2002 and 2021 in Hong-Kong, using territory-wide medical-record database of public-healthcare services, to investigate whether depression increased the risk of overall mortality, complications and post-complication mortality in people with diabetes. Associations of depression with all-cause mortality, complication and post-complication all-cause mortality rates were examined by Cox proportional-hazards model. Complications were assessed by Diabetes-Complications-Severity-Index (DCSI). Associations of complications, in terms of DCSI scores (complication burden), specific types and two-way combinations of complications (complication patterns) with all-cause mortality rate in depression were also examined. Our results showed that depression-diabetes group exhibited increased all-cause mortality risk (adjusted hazards-ratio: 1.06 [95 %CI: 1.02–1.10]) relative to diabetes-only group, particularly among men and older age group, with significantly higher rate of experiencing neuropathy (1.44 [1.27–1.62]) and metabolic complications (1.30 [1.09–1.56]) and lower likelihood of peripheral-vascular complications, retinopathy and nephropathy, albeit comparable macrovascular and microvascular complication rates. The mortality-rate-ratio for patients with depression and diabetes was significantly higher than patients with diabetes-only at a low level of complication burden. In conclusion, depression patients with co-occurring diabetes are at increased risk of excess mortality. Further research is warranted to improve diabetes-related outcomes and reduce mortality gap in this vulnerable population.</p
Diagnostic Accuracy of a Point‐Of‐Care aMMP‐8 Test for Discriminating Periodontal Health Status in Adults: Validation Trials and Updated Meta‐Analysis
Full text linkAimTo evaluate the diagnostic accuracy of an active matrix metalloproteinase-8 (aMMP-8) point-of-care oral rinse test (POC-ORT) for predicting periodontitis in treatment-naïve subjects in two independent studies and update a recent meta-analysis.MethodsThe aMMP-8 POC-ORT index test was performed in a representative population in Hong Kong, China, and a consecutive convenience sample in Shanghai, China. The reference standard was the 2017 World Workshop classification of periodontal diseases. Sensitivity, specificity, and the area under the receiver operating characteristic (AUROC) curve were assessed. The original data were used to update a recent Bayesian meta-analysis following the current Cochrane guideline for diagnostic trials. The GRADE framework was used to interpret the strength and certainty of the evidence.ResultsThree-hundred and eighty-four and 390 subjects were enrolled in the Hong Kong and Shanghai studies, respectively; 74.5% and 67.2% had periodontitis. An aMMP-8-positive test predicted periodontitis with an AUROC of 0.661 and 0.669 in the two studies. The updated systematic review and meta-analysis included eight studies and 2048 subjects. After considering the risk of bias, indirectness, inconsistency, imprecision and publication bias, it showed moderate certainty of a sensitivity of 0.59 (95% CrI: 0.42–0.75), a specificity of 0.82 (95% CrI: 0.68–0.93) and a hierarchical summary AUROC of 0.77 (95% CrI: 0.74–0.81).ConclusionThere is moderate certainty that the aMMP-8 POC-ORT test predicts periodontitis with low to moderate sensitivity, moderate to high specificity, and moderate accuracy. Its high false-negative rate does not allow the replacement of clinical examinations when available. The moderate to high positive predictive value shows the potential utility of a positive test for self-detection or co-management of periodontitis in a medical setting and its incorporation in multi-test diagnostics. Further investigations are highly warranted.published_or_final_versio
Solving climate change requires changing our food systems
Full text linkHumanity is facing an important existential threat—irreversible climate change caused by human activity. Until recently, most of the proposals to address climate change have downplayed or ignored the adverse impact of food systems, especially intensive animal agriculture. This is in spite of the fact that up to a third of global greenhouse gas production to date can be attributed to animal agriculture. Recent developments at COP28 have signaled that the tide is turning, however, and that food systems are becoming part of global discussions on climate change solutions. The pressing nature of irreversible climate change requires rethinking our food systems. To solve the climate change crisis, we propose transitioning to a predominantly plant-based diet, and phasing out intensive animal agriculture as diets shift, without increasing pastoral farming. We suggest that such transformations in global food systems can be accomplished largely through education and large-scale public information campaigns, removal of subsidies, taxation to account for externalized costs of animal agriculture, improved labelling of products, and various investment/divestment drivers. Better metrics and industry benchmarks involving food and agriculture-specific performance indicators that reflect food system sustainability will be important. Increased global awareness of these issues and a change in mindset (which will drive political will) also are needed. Our current trajectory is untenable, and we must begin to turn the ship now towards sustainable food systems and diets.published_or_final_versio
Application of Family Stress Theory: Predicting Wellbeing by Demands, Resources and Perceptions Among Caregivers of Older Adults
No full textFamily caregivers of older adults are at risk of high care burden and reduced quality of life. Existing research and practices had primarily focused on the caregiving dyad. However, it is often observed that multiple family members are involved in caregiving for older adults. We applied family stress theory to understand family caregiving and examined how care demands, resources, and perceptions are associated with and predict caregiver well-being. Participants in this study were low-income family caregivers who received caregiver allowance and provided care for an older adult with care needs in the community in Hong Kong. Two waves of data, including baseline data from 358 caregivers and 2-year follow-up data from a subsample of 93 caregivers, were collected. We used hierarchical regression to predict care burden and quality of life at baseline and follow-up, respectively, by care demands, resources, and perceptions after controlling for the context of care. Results show that additional caregiving roles, quality of relationship with the older adult, and satisfaction with family support were associated with care burden and quality of life at baseline. Predictors of lower care burden at 2-year follow-up were discontinuation of additional caregiving roles, increase in size of caregiving family, and the use of domestic helper. Applying family stress theory to understand the caregiving process reveals the significance of additional caregiving roles, the involvement of multiple caregivers, and caregivers' perceptions about family support in enhancing caregiver well-being, underscoring the need to focus on these factors when designing and implementing caregiver support services.</p