A Model for Partial Viscous Sintering

A mathematical model describing the sintering rate of a viscous material powder bed is presented. This model assumes that the powder bed is composed of cubic packed, equal-size spherical particles. The sintering rate equation is derived in terms of a unit cell dimension or the relative density of a powder bed. A mathematical factor, fraction of sintering, is introduced to explain the phenomena of partial sintering. Key words: model, viscous sintering.Mechanical Engineerin

Goal-Focused Emotion-Regulation Therapy (GET) for young adult survivors of testicular cancer: a pilot randomized controlled trial of a biobehavioral intervention protocol.

BackgroundTesticular cancer diagnosis and treatment, especially given its threat to sexuality and reproductive health, can be distressing in the formative period of young adulthood and the majority of young survivors experience impairing, distressing, and modifiable adverse outcomes that can persist long after medical treatment. These include psychological distress, impairment in pursuit of life goals, persistent physical side effects, elevated risk of secondary malignancies and chronic illness, and biobehavioral burden (e.g., enhanced inflammation, dysregulated diurnal stress hormones). However, few targeted interventions exist to assist young survivors in renegotiating life goals and regulating cancer-related emotions, and none focus on reducing the burden of morbidity via biobehavioral mechanisms. This paper describes the methodology of a randomized controlled biobehavioral trial designed to investigate the feasibility and preliminary impact of a novel intervention, Goal-focused Emotion-Regulation Therapy (GET), aimed at improving distress symptoms, emotion regulation, goal navigation skills, and stress-sensitive biomarkers in young adult testicular cancer patients.MethodsParticipants will be randomized to receive six sessions of GET or Individual Supportive Therapy (ISP) delivered over 8 weeks. In addition to indicators of intervention feasibility, we will measure primary (depressive and anxiety symptoms) and secondary (emotion regulation and goal navigation skills, career confusion) psychological outcomes prior to (T0), immediately after (T1), and 12 weeks after (T2) intervention. Additionally, identified biomarkers will be measured at baseline and at T2.DiscussionGET may have the potential to improve self-regulation across biobehavioral domains, improve overall cancer adjustment, and address the need for targeted supportive care interventions for young adult cancer survivors.Trial registrationClinicaltrials.gov, NCT04150848. Registered on 28 October 2019

The Rumsfeld Paradigm: Knowns and Unknowns in Characterizing Habitats Used by the Endangered Sharp-tailed Snake, Contia tenuis, in Southwestern British Columbia

The Sharp-tailed Snake, Contia tenuis, has a small and highly fragmented range in British Columbia, where it is considered endangered. Known sites are few in number and generally small in spatial extent; numbers of snakes apparently are correspondingly low. Furthermore, most known sites for the species are on private lands in areas that are fairly heavily developed or being developed. Thus, the species is under serious threat of habitat alteration or loss. Although land stewardship has been a valuable conservation tool in this case, we also need to identify the key habitat requirements of Sharp-tailed Snakes to identify potential new sites, modify former or potential ones, or even create new ones. In this study, we compared sites known to harbour Sharp-tailed Snakes with those that seemed subjectively similar and therefore potentially suitable. We also compared these known and potential sites with randomly chosen nearby locations. Variability of most measured features was high, both within and among site/location categories. Nonetheless, we found significant differences between known and potential sites and between those locations and random ones. Overall, locations known to be used by snakes had a more southerly aspect, more rock cover, shallower soil and litter, and less shrub cover than other sites. This study was constrained by the small number of known sites for Sharp-tailed Snakes in southwestern British Columbia, making our conclusions suggestive rather than definitive. Future work should incorporate additional variables. It also might be useful to undertake comparative habitat studies elsewhere in the range of the Sharp-tailed Snake where it is more common

Magnetoelectrically driven catalytic degradation of organics

Here, we report the catalytic degradation of organic compounds by exploiting the magnetoelectric (ME) nature of cobalt ferrite-bismuth ferrite (CFO-BFO) core-shell nanoparticles. The combination of magnetostrictive CFO with the multiferroic BFO gives rise to a magnetoelectric engine that purifies water under wireless magnetic fields via advanced oxidation processes, without involvement of any sacrificial molecules or co-catalysts. Magnetostrictive CoFe2O4 nanoparticles are fabricated using hydrothermal synthesis, followed by sol-gel synthesis to create the multiferroic BiFeO3 shell. We perform theoretical modeling to study the magnetic field induced polarization on the surface of magnetoelectric nanoparticles. The results obtained from these simulations are consistent with the experimental findings of the piezo-force microscopy analysis, where we observe changes in the piezoresponse of the nanoparticles under magnetic fields. Next, we investigate the magnetoelectric effect induced catalytic degradation of organic pollutants under AC magnetic fields and obtained 97% removal efficiency for synthetic dyes and over 85% removal efficiency for routinely used pharmaceuticals. Additionally, we perform trapping experiments to elucidate the mechanism behind the magnetic field induced catalytic degradation of organic pollutants by using scavengers for each of the reactive species. Our results indicate that hydroxyl and superoxide radicals are the main reactive species in the magnetoelectrically induced catalytic degradation of organic compounds

Large Intelligent Surface Measurements for Joint Communication and Sensing

Multiple concepts for future generations of wireless communication standards utilize coherent processing of signals from many distributed antennas. Names for these concepts include distributed MIMO, cell-free massive MIMO, XL-MIMO, and large intelligent surfaces. They aim to improve communica- tion reliability, capacity, as well as energy efficiency and provide possibilities for new applications through joint communication and sensing. One such recently proposed solution is the concept of RadioWeaves. It proposes a new radio infrastructure for distributed MIMO with distributed internal processing, storage and compute resources integrated into the infrastructure. The large bandwidths available in the higher bands have inspired much work regarding sensing in the mmWave- and sub-THz- bands, however, sub-6 GHz cellular bands will still be the main provider of broad cellular coverage due to the more favorable propagation conditions. In this paper, we present results from a sub-6 GHz measurement campaign targeting the non-stationary spatial channel statistics for a large RadioWeave and the temporal non-stationarity in a dynamic scenario with RadioWeaves. From the results, we also predict the possibility of multi-static sensing and positioning of users in the environment

Evaluation of the impact of a school gardening intervention on children's fruit and vegetable intake: a randomised controlled trial.

Background: Current academic literature suggests that school gardening programmes can provide an interactive environment with the potential to change children’s fruit and vegetable intake. This is the first cluster randomised controlled trial (RCT) designed to evaluate whether a school gardening programme can have an effect on children’s fruit and vegetable intake. Methods: The trial included children from 23 schools; these schools were randomised into two groups, one to receive the Royal Horticultural Society (RHS)-led intervention and the other to receive the less involved Teacher-led intervention. A 24-hour food diary (CADET) was used to collect baseline and follow-up dietary intake 18 months apart. Questionnaires were also administered to evaluate the intervention implementation. Results: A total of 641 children completed the trial with a mean age of 8.1 years (95% CI: 8.0, 8.4). The unadjusted results from multilevel regression analysis revealed that for combined daily fruit and vegetable intake the Teacher-led group had a higher daily mean change of 8 g (95% CI: −19, 36) compared to the RHS-led group -32 g (95% CI: −60, −3). However, after adjusting for possible confounders this difference was not significant (intervention effect: −40 g, 95% CI: −88, 1; p = 0.06). The adjusted analysis of process measures identified that if schools improved their gardening score by 3 levels (a measure of school gardening involvement - the scale has 6 levels from 0 ‘no garden’ to 5 ‘community involvement’), irrespective of group allocation, children had, on average, a daily increase of 81 g of fruit and vegetable intake (95% CI: 0, 163; p = 0.05) compared to schools that had no change in gardening score. Conclusions: This study is the first cluster randomised controlled trial designed to evaluate a school gardening intervention. The results have found very little evidence to support the claims that school gardening alone can improve children’s daily fruit and vegetable intake. However, when a gardening intervention is implemented at a high level within the school it may improve children’s daily fruit and vegetable intake by a portion. Improving children’s fruit and vegetable intake remains a challenging task

Exposure to Household Air Pollution from Biomass Cookstoves and Blood Pressure Among Women in Rural Honduras: A Cross‐Sectional Study

Growing evidence links household air pollution exposure from biomass cookstoves with elevated blood pressure. We assessed cross‐sectional associations of 24‐hour mean concentrations of personal and kitchen fine particulate matter (PM2.5), black carbon (BC), and stove type with blood pressure, adjusting for confounders, among 147 women using traditional or cleaner‐burning Justa stoves in Honduras. We investigated effect modification by age and body mass index. Traditional stove users had mean (standard deviation) personal and kitchen 24‐hour PM2.5 concentrations of 126 μg/m3 (77) and 360 μg/m3 (374), while Justa stove users’ exposures were 66 μg/m3 (38) and 137 μg/m3(194), respectively. BC concentrations were similarly lower among Justa stove users. Adjusted mean systolic blood pressure was 2.5 mm Hg higher (95% CI, 0.7‐4.3) per unit increase in natural log‐transformed kitchen PM2.5 concentration; results were stronger among women of 40 years or older (5.2 mm Hg increase, 95% CI, 2.3‐8.1). Adjusted odds of borderline high and high blood pressure (categorized) were also elevated (odds ratio = 1.5, 95% CI, 1.0‐2.3). Some results included null values and are suggestive. Results suggest that reduced household air pollution, even when concentrations exceed air quality guidelines, may help lower cardiovascular disease risk, particularly among older subgroups

A multicenter, randomized, controlled trial of totally percutaneous access versus open femoral exposure for endovascular aortic aneurysm repair (the PEVAR trial)

ObjectiveThe first multicenter randomized controlled trial was designed and conducted to assess the safety and effectiveness of totally percutaneous endovascular aortic aneurysm repair (PEVAR) with use of a 21F endovascular stent graft system and either an 8F or 10F suture-mediated closure system (the PEVAR trial, NCT01070069). A noninferiority trial design was chosen to compare percutaneous access with standard open femoral exposure.MethodsBetween 2010 and 2012, 20 U.S. institutions participated in a prospective, Food and Drug Administration–approved randomized trial to evaluate percutaneous femoral artery access and closure by a “preclose” technique in conjunction with endovascular abdominal aortic aneurysm repair. A total of 151 patients were allocated by a 2:1 design to percutaneous access/closure (n = 101) or open femoral exposure (n = 50 [FE]). PEVAR procedures were performed with either the 8F Perclose ProGlide (n = 50 [PG]) or the 10F Prostar XL (n = 51 [PS]) closure devices. All endovascular abdominal aortic aneurysm repair procedures were performed with the Endologix 21F profile (outer diameter) sheath-based system. Patients were screened by computed tomography with three-dimensional reconstruction and independent physician review for anatomic suitability and adequate femoral artery anatomy for percutaneous access. The primary trial end point (treatment success) was defined as procedural technical success and absence of major adverse events and vascular complications at 30 days. An independent access closure substudy evaluated major access-related complications. Clinical utility and procedural outcomes, ankle-brachial index, blood laboratory analyses, and quality of life were also evaluated with continuing follow-up to 6 months.ResultsBaseline characteristics were similar among groups. Procedural technical success was 94% (PG), 88% (PS), and 98% (FE). One-month primary treatment success was 88% (PG), 78% (PS), and 78% (FE), demonstrating noninferiority vs FE for PG (P = .004) but not for PS (P = .102). Failure rates in the access closure substudy analyses demonstrated noninferiority of PG (6%; P = .005), but not of PS (12%; P = .100), vs FE (10%). Compared with FE, PG and PS yielded significantly shorter times to hemostasis and procedure completion and favorable trends in blood loss, groin pain, and overall quality of life. Initial noninferiority test results persist to 6 months, and no aneurysm rupture, conversion to open repair, device migration, or stent graft occlusion occurred.ConclusionsAmong trained operators, PEVAR with an adjunctive preclose technique using the ProGlide closure device is safe and effective, with minimal access-related complications, and it is noninferior to standard open femoral exposure. Training, experience, and careful application of the preclose technique are of paramount importance in ensuring successful, sustainable outcomes