bluuebunny/crossref_metadata_2025 huggingface dataset:
Hepato‐protective role of chemo‐preventive probiotics during DMH‐induced CRC in rats
Authors: Walia Sohini , Kamal Rozy , Kanwar Sarbjit S. , Dhawan Devinder K.
Published: April 2021

The aim of the study was to assess the hepatotoxicity, and therefore pharmacological safety of probiotics Lactobacillus plantarum (AdF10) and Lactobacillus rhamnosus GG (LGG) for potential use in colorectal cancer (CRC) prevention. Thirty‐six female Sprague Dawley (SD) rats were divided into six groups: normal control, AdF10‐treated, LGG‐treated, 1,2‐Dimethyl hydrazine (DMH)‐treated, AdF10 + DMH‐treated, and LGG + DMH‐treated groups. Antioxidant enzyme activity, lipid proxidation, and liver function were assessed. Administration of probiotics in both AdF10 + DMH‐treated and LGG + DMH‐treated groups downregulated DMH induced a rise in lipid peroxide (LPO), glutathione reductase (GR) activity, and increased the diminished glutathione reduced (GSH) content and catalase (CAT), glutathione‐transferase (GST), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities. DMH‐treated rats receiving the probiotic treatment suffered less liver damage when compared with rats that did not receive probiotics. In conclusion, the study identifies the use of probiotics as an effective and nontoxic chemo‐preventive interventional in CRC.
Bacterial resistance to minocycline after adjunctive minocycline microspheres during periodontal maintenance: A randomized clinical trial
Authors: Teles Flavia R. F. , Lynch Michael C. , Patel Michele , Torresyap Gay , Martin Lynn
Published: April 2021

Background

Despite widespread use, the impact of minocycline hydrochloride microspheres on the shifts of oral bacterial species resistant to minocycline remains unknown. This study aimed at examining the percentage and taxonomy of minocycline‐resistant isolates in saliva and subgingival plaque samples before and after minocycline microspheres application in periodontitis patients during maintenance.

Methods

Patients received supra‐ and sub‐gingival debridement with (test) or without (control) minocycline microspheres application to sites with probing depth >4 mm and were clinically monitored at baseline, 1, 3, and 6 months. Samples were collected at baseline, 1 and 6 months and analyzed via cultivation with or without 4 μg/mL minocycline. Percentage of resistant strains was determined by colony counting and taxonomy by checkerboard DNA‐DNA hybridization. Significant clinical changes were sought with the Mann‐Whitney test and differences in percentage of resistant isolates with the Friedman and Mann‐Whitney tests.

Results

Groups showed similar clinical improvements. Mean percentage of resistant isolates rose at 1 month and decreased at 6 months in saliva and plaque samples in test group (P <0.05) but remained unchanged in control group. Percentage of resistant isolates of Gemella morbillorum and Eubacterium saburreum increased significantly at 6 months in both groups. Antibiotic resistance by Aggregatibacter actinomycetemcomitans, Tannerella forsythia, and Porphyromonas gingivalis was either absent or infrequent.

Conclusion

Minocycline microspheres result in transient selection of minocycline resistant species in saliva and subgingival plaque samples.
The disclosure slide—Informative or obligatory, 5 years of SSO Cancer Symposium oral presentations
Authors: Merritt William , Robergé Bouchard David , Ford Candice , Lozano Alicia , Xu Yang , Hanlon Alexandra , Petrelli Nicholas , Tiesi Gregory
Published: April 2021

Background

Financial disclosure (FD) highlights potential conflicts of interest but is often overlooked at academic conferences.

Methods

Retrospective review of 2015–2019 Society of Surgical Oncology Cancer Symposium oral presentation slide and/or verbal FD frequency, duration, and content.

Results

Of 963 presentations, 331 (34%) omitted disclosure slide/verbalization. 575 (60%) included a slide, 551 (57%) gave verbal disclosure and 133 (14%) stated relevance. 164 presentations (17%) cited 1 + FD. 2019 had greater median FDs/talk than 2015–2018 (3.50 vs. 2.00; p = .010).

Compared to 2015–2018, 2019 yielded shorter median slide display of all disclosures (2.00 s vs. 2.47 s; p = .006), median 1 + FD display (3.37 s vs. 4.81 s; p = .04) and median 1 + FD verbalization (2.81 s vs. 3.66 s; p = .54). 2019 all disclosure verbalization increased (1.97 s vs. 1.14 s; p < .001).

Multivariable modeling showed longer display with 2015–2018 (+1.3 s, 95% confidence interval [CI] −0.06 to 2.5 s, p = .04), <4 authors (+3.2 s, 95% CI: 2.1–4.3 s; p < .001) and longer verbalization with 2019 (+0.8 s, 95% CI: 0.2–1.4 s; p = .01), relevance (+1.0 s, 95% CI: 0.4–1.6 s; p = .002), ≤ 4 authors (+0.8 s, 95% CI: 0.3–1.3 s, p < .001) and noncommercial FD (+3.8 s, 95% CI: 2.0–5.0 s; p < .001).

The five most cited commercial entities were in 39% of talks.

Conclusion

Presenters' FDs were brief or omitted. Despite FD increase, disclosure time decreased. Improved FD attention will highlight potential COIs.
Low‐dose preoperative radiation, resection, and reduced‐field postoperative radiation for soft tissue sarcomas
Authors: Konieczkowski David J. , Goldberg Saveli I. , Raskin Kevin A. , Lozano‐Calderon Santiago , Mullen John T. , Chen Yen‐Lin , DeLaney Thomas F.
Published: April 2021

Background and Objectives

Radiotherapy (RT) enables conservative surgery for soft tissue sarcoma (STS). RT can be delivered either pre‐operatively (PreRT) or postoperatively (PORT), yet in some patients, neither approach is fully satisfactory (e.g., urgent surgery or wound healing risk prevents PreRT, yet PORT alone cannot cover the entire surgical field). We hypothesized that, in such situations, low‐dose PreRT (LD‐PreRT) would decrease the risk of intraoperative tumor seeding and thus permit PORT to a reduced volume (covering the high‐risk tumor bed but not all surgically manipulated tissues).

Methods

We identified a single‐institution retrospective cohort of 78 patients treated with LD‐PreRT (10–30 Gy), resection, and PORT between 1980 and 2018.

Results

At a median follow‐up of 8.2 years, 8‐year overall survival (OS) was 65.9%, disease‐free survival (DFS) 50.5%, and local control (LC) 76.7%; in 45 patients with extremity/superficial trunk (E/ST) STS, 8‐year LC was 80.9%. Both before and after propensity score adjustment, there were no differences in OS, DFS, or LC between this cohort and a separate cohort of 394 STS (221 E/ST‐STS) patients treated with surgery and PORT alone.

Conclusions

In patients for whom neither PreRT nor PORT alone is optimal, LD‐PreRT may prevent intraoperative tumor seeding and enable PORT to a reduced volume while preserving oncologic outcomes.
Optimizing the frame duration for data‐driven rigid motion estimation in brain PET imaging
Authors: Spangler‐Bickell Matthew G. , Hurley Samuel A. , Deller Timothy W. , Jansen Floris , Bettinardi Valentino , Carlson Mackenzie , Zeineh Michael , Zaharchuk Greg , McMillan Alan B.
Published: April 2021

Purpose

Data‐driven rigid motion estimation for PET brain imaging is usually performed using data frames sampled at low temporal resolution to reduce the overall computation time and to provide adequate signal‐to‐noise ratio in the frames. In recent work it has been demonstrated that list‐mode reconstructions of ultrashort frames are sufficient for motion estimation and can be performed very quickly. In this work we take the approach of using image‐based registration of reconstructions of very short frames for data‐driven motion estimation, and optimize a number of reconstruction and registration parameters (frame duration, MLEM iterations, image pixel size, post‐smoothing filter, reference image creation, and registration metric) to ensure accurate registrations while maximizing temporal resolution and minimizing total computation time.

Methods

Data from 18F‐fluorodeoxyglucose (FDG) and 18F‐florbetaben (FBB) tracer studies with varying count rates are analyzed, for PET/MR and PET/CT scanners. For framed reconstructions using various parameter combinations interframe motion is simulated and image‐based registrations are performed to estimate that motion.

Results

For FDG and FBB tracers using 4 × 105 true and scattered coincidence events per frame ensures that 95% of the registrations will be accurate to within 1 mm of the ground truth. This corresponds to a frame duration of 0.5–1 sec for typical clinical PET activity levels. Using four MLEM iterations with no subsets, a transaxial pixel size of 4 mm, a post‐smoothing filter with 4–6 mm full width at half maximum, and averaging two or more frames to create the reference image provides an optimal set of parameters to produce accurate registrations while keeping the reconstruction and processing time low.

Conclusions

It is shown that very short frames (≤1 sec) can be used to provide accurate and quick data‐driven rigid motion estimates for use in an event‐by‐event motion corrected reconstruction.
Multi‐objective optimization of wear performance of epoxy composites by gray‐based response surface methodology
Authors: Dharmalingam Satish Kumar , Murugesan Rajmohan
Published: April 2021

This study is to optimize the tribological performances of epoxy (plain), composite of epoxy/strand mat E‐glass fiber, and hybrid composite of epoxy/strand mat E‐glass fiber/carbon (particles). Experiments are carried with respect to central composite design in response surface methodology. Input parameters like speed (N), load (L), sliding distance (D) along with three different samples (S) were considered for the study. Gray relational analysis based on response surface design method is embraced to identify optimal parameters for attaining minimum weight loss and minimum coefficient of friction. According to this study, epoxy/E‐glass fiber/carbonp composite were found to have good wear resistance as well as lower coefficient of friction.
Prenatal exposure to non‐steroidal anti‐inflammatory drugs and risk of attention‐deficit/hyperactivity disorder: A follow‐up study in the Norwegian mother, father and child cohort
Authors: Hjorth Sarah , Lupattelli Angela , Handal Marte , Spigset Olav , Ystrom Eivind , Nordeng Hedvig
Published: April 2021

Purpose

To estimate the association between Attention‐Deficit/Hyperactivity Disorder (ADHD) in children in preschool and primary school, and prenatal exposure to non‐steroidal anti‐inflammatory drugs (NSAIDs) by timing and duration.

Methods

This study was based on the Norwegian Mother, Father and Child Cohort Study linked to the Medical Birth Registry of Norway, the Norwegian Patient Registry (NPR) and the Norwegian Prescription Database (NorPD). NSAID exposure was identified by maternal self‐report in pregnancy. Child diagnosis of ADHD was obtained from NPR and NorPD. Symptoms of ADHD at age 5 years were measured using Conners' Parent Rating Scale‐Revised, where higher scores correspond to more symptoms. To account for time‐varying exposure and confounders, marginal structural models were fitted to estimate hazard ratios and mean difference in z‐scores.

Results

The analyses on ADHD diagnosis and ADHD symptoms included 56 340 and 34 961 children respectively. Children exposed to NSAIDs prenatally had no increased risk of ADHD diagnosis (first trimester: HR 1.12, 95% CI 0.86;1.45, second trimester: HR 0.98, 95% CI 0.69;1.38, third trimester: HR 0.68, 95% CI 0.31; 1.46) or ADHD symptoms (first trimester: standardized mean difference 0.03, 95% CI −0.03;0.09, second trimester: standardized mean difference 0.03, 95% CI −0.04;0.11, third trimester: standardized mean difference 0.11, 95% CI −0.03; 0.25). There was no duration‐response relationship for either outcome.

Conclusion

Though non‐differential misclassification of the exposure may have attenuated results, these findings are reassuring and suggest no substantially increased risk of ADHD diagnosis or symptoms in children prenatally exposed to NSAIDs, regardless of timing or duration.
Knee extensor power predicts six‐minute walk test performance in people with transfemoral amputations
Authors: Slater Lindsay , Finucane Suzanne , Hargrove Levi J.
Published: April 2021

Background

Lower‐limb amputees have increased metabolic costs during walking that may be mitigated by maintaining quadriceps strength and power following amputation. However, there are no current studies investigating the relationship between thigh strength and walking performance in individuals with transfemoral amputation.

Objective

To quantify the relationship between intact limb quadriceps strength in transfemoral amputees and six‐minute walk test (6MWT) performance.

Design

Descriptive laboratory study.

Setting

Laboratory.

Participants

Eleven participants with unilateral transfemoral amputations from trauma or osteosarcoma (4 women/7 men, 46.21 ± 12.68 years old, 28.24 ± 20.57 years following amputation).

Interventions

Strength and power testing on the intact limb followed by 6MWT with a flowmeter to measure oxygen uptake (VO2).

Main Outcome Measures

Strength included mass‐normalized peak torque, average torque, and average power. 6MWT measures included total distance traveled and VO2 normalized to distance and mass. Significant correlations (P ≤ .05) were retained for a regression analysis.

Results

Peak isokinetic knee extensor torque was correlated with total VO2 (r = −.60, P = .05) and distance traveled (r = .84, P = .001). Average isokinetic knee extensor torque was correlated with total VO2 (r = −.61, P = .046) and distance traveled (r = .85, P = .001). Average knee extensor power was correlated with total VO2 (r = −.67, P = .026) and distance traveled (r = .88, P < .001). Peak isometric knee extensor torque was correlated with distance traveled (r = .69, P = .019). Average power explained 77.2% of the variance in distance traveled during the 6MWT (P < .001) and average power explained 44.2% of the variance in total VO2 during the 6MWT (P = .026).

Conclusions

Knee extensor strength was correlated with performance on the 6MWT in individuals with unilateral transfemoral amputation. The strongest relationship was between isokinetic quadriceps power and distance traveled, which suggests that developing quadriceps power in the intact limb following amputation may be an important factor to reduce metabolic cost of walking and support a return to an active lifestyle.
Study on the synthesis and theoretical calculation of a chlorine‐substituted thiosemicarbazone derivative
Authors: Wei Chenli , Wang Sifan , Deng Jingwen , Guo Zeyu , Qi Fan , Huang Jie
Published: April 2021

In this paper, the compound (E)‐N‐(3,5‐dimethylphenyl)‐2‐(3‐chlorobenzylidene)thiosemicarb‐azone was synthesized and characterized by elemental analysis, Fourier transform infrared (FT‐IR), 1H nuclear magnetic resonance (NMR), 13C NMR. The crystal structure was determined by single‐crystal X‐ray diffraction tool, indicating that the compound belongs to the orthorhombic crystal system of the Fdd2 space group, where a = 14.0472(12) Å, b = 57.148(4) Å, c = 7.9633(6) Å, the chemical formula is C16H16ClN3S, Mr = 317.83, V = 6392.7(9) Å3, Z = 16, Dc = 1.321 Mg/m3, F(000) = 2656, R = 0.0339, wR = 0.0903. Analysis of crystal data shows that the molecular conformation has good planarity. Hirshfeld surface and two‐dimensional (2D) fingerprints were used to analyze the intermolecular hydrogen bonds. In addition, a more comprehensive theoretical calculation studies were carried out on synthetic compound, such as potential energy surface (PES) scan, reduced density gradient (RDG), and independent gradient model (IGM) analysis, atoms in molecules (AIM) analysis, highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) and UV‐visible spectra analysis. The combination of experimental and theoretical data proved that non‐covalent bonds play a vital role in maintaining the stability of molecule. Finally, molecular docking was used to research the interaction between the synthetic compound and the receptor protein (4C2L). Meanwhile, the results obtained by in vitro antifungal assay indicated that the synthetic compound possesses the most remarkable inhibitory effect for Fusarium graminearum.
Modeled (1990–2100) variations in active‐layer thickness and ice‐wedge activity near Salluit, Nunavik (Canada)
Authors: Gagnon Samuel , Allard Michel
Published: April 2021

Simulations with a one‐dimensional heat transfer model (TONE) were performed to reproduce the near surface ground temperature regime in the four main types of soil profiles found in Narsajuaq River Valley (Nunavik, Canada) for the period 1990–2100. The permafrost thermal regime was simulated using climate data from a reanalysis (1948–2002), climate stations (1989–1991, 2002–2019) and simulations based on climate warming scenarios RCP4.5 and RCP8.5 (2019–2100). The model was calibrated based on extensive field measurements made between 1989 and 2019. The results were used to estimate when soil thermal contraction cracking will eventually stop and to forecast the melting of ice wedges due to active‐layer thickening. For the period 1990–2019, all soil profiles experienced cracking every year until 2006, when cracking became intermittent during a warm period before completely stopping in 2009–2010, after which cracking resumed during colder years. Ice‐wedge tops melted from 1992 to 2010 as the active layer thickened, indicating that top‐down ice‐wedge degradation can occur simultaneously with cracking and growth in width. Our predictions show that ice wedges in the valley will completely stop cracking between 2024 and 2096, first in sandy soils and later in soils with thicker organic horizons. The timing will also depend on greenhouse gas concentration trajectories. All ice wedges in the study area will probably experience some degradation of their main body before the end of the century, causing their roots to become relict ice by the end of the 21st century.
Large trees in tropical rain forests require big plots
Authors: Harris David J. , Ndolo Ebika Sydney T. , Sanz Crickette M. , Madingou Mady P.N. , Morgan David B.
Published: April 2021

Societal Impact Statement

Globally, the conservation value of big trees is linked to biodiversity and carbon sequestration. We studied trees, greater than 80 cm in diameter, in a forest in the Republic of Congo. We found that more than 100 species reach this size and the most abundant species is Sapele (Entandrophragma cylindricum), which is exploited for global timber markets. More than 40% of the large tree species are used by local people for food. Our results show that big trees are important to local people in the Congo Basin in addition to being the focus of industrial logging and in many areas the basis for the formal economy.

The main aim of this paper is to establish standard techniques for surveying the biggest trees in tropical rain forests.

One hundred and thirty hectares (13 plots of 10 ha) of unlogged mixed species terra firma forest in the Republic of Congo were surveyed for trees greater than 80 cm in diameter.

More than 100 species of tree exceed 80 cm in diameter and one species, Entandrophragma cylindricum (Sapele or Sapelli), dominates this size class.

Obtaining comparable data of big trees from different sites across the tropics is a priority. We propose a standardised plot size of 10 ha, replicated 10 times for each forest type at different study sites and a minimum trunk diameter of 70 cm at breast height or above buttresses.
Thoracoabdominal asynchrony and paradoxical motion in Duchenne muscular dystrophy and healthy subjects during cough: A case control study
Authors: Marques Layana , Fregonezi Guilherme Augusto de Freitas , Marcelino Ana Aline , Dourado‐Júnior Mario Emílio Teixeira , Sarmento Antonio , Pennati Francesca , Aliverti Andrea , Resqueti Vanessa Regiane
Published: April 2021

Objective

To assess thoracoabdominal asynchrony (TAA) and inspiratory paradoxical motion at different positionings in subjects with Duchenne muscular dystrophy (DMD) versus healthy subjects during quiet spontaneous breathing (QB) and cough.

Methods

This is a case control study with a matched‐pair design. We assessed 14 DMD subjects and 12 controls using optoelectronic plethysmography (OEP) during QB and spontaneous cough in 3 positions: supine, supine with headrest raised at 45°, and sitting with back support at 80°. The TAA was assessed using phase angle (θ) between upper (RCp) and lower rib cage (RCa) and abdomen (AB), as well as the percentage of inspiratory time the RCp (IPRCp), RCa (IPRCa), and AB (IPAB) moved in opposite directions.

Results

During cough, DMD group showed higher RCp and RCa θ (p < .05), RCp and AB θ (p < .05) in supine and 45° positions, and higher RCp and Rca θ (p = .006) only in supine position compared with controls. Regarding the intragroup analysis, during cough, DMD group presented higher RCp and AB θ (p = .02) and RCa and AB θ (p = .002) in supine and higher RCa and AB θ (p = .002) in 45° position when compared to 80°. Receiver operating characteristic curve analyzes were able to discriminate TAA between controls and DMD in RCa supine position (area under the curve: 0.81, sensibility: 78.6% and specificity: 91.7%, p = .001).

Conclusion

Subjects with DMD yields TAA with insufficient deflation of chest wall compartments and rib cage distortion during cough, by noninvasive assessment.
Reading Volume and Reading Achievement: A Review of Recent Research
Authors: Allington Richard L. , McGill-Franzen Anne M.
Published: April 2021

Although there have been a substantial number of research studies focused on improving the field’s understanding of the development of the ability to read, very few of these studies have accounted for the potential role that extensive engagement in the act of reading might play in the development of reading proficiency. There are several views on the role, if any, that extensive reading plays in reading development. In this article, using research published since 2000, the evidence that reading volume plays a role in reading development now seems clearer.
Structural performance of superframed conjoined towers
Authors: Moon Kyoung Sun
Published: April 2021

Tall buildings have generally been developed as solo towers. As tall buildings become ever taller, how to produce reasonably increased structural depths against lateral wind loads and maintain desirable lease depths simultaneously are critical design considerations. Conjoined towers have great potential to resolve these structural and architectural design issues holistically. While many different structural configurations are possible for conjoined towers, the concept of superframed conjoined towers is a viable option for superior performance. In the superframed conjoined towers studied in this paper, multiple braced tube towers are connected also with horizontal braced tube link structures. Various parameters of the link structures, such as stiffness, numbers, and locations, impact the structural performance of the superframed conjoined towers. As the structural design of tall buildings is generally governed by lateral stiffness, this paper investigates the lateral performance of superframed conjoined towers with variously configured link structures. While emphasis is placed on static responses in relation to architectural design, basic dynamic properties are also studied.
Enhancing models of social and strategic decision making with process tracing and neural data
Authors: Konovalov Arkady , Ruff Christian C.
Published: April 2021

Every decision we take is accompanied by a characteristic pattern of response delay, gaze position, pupil dilation, and neural activity. Nevertheless, many models of social decision making neglect the corresponding process tracing data and focus exclusively on the final choice outcome. Here, we argue that this is a mistake, as the use of process data can help to build better models of human behavior, create better experiments, and improve policy interventions. Specifically, such data allow us to unlock the “black box” of the decision process and evaluate the mechanisms underlying our social choices. Using these data, we can directly validate latent model variables, arbitrate between competing personal motives, and capture information processing strategies. These benefits are especially valuable in social science, where models must predict multi‐faceted decisions that are taken in varying contexts and are based on many different types of information.

This article is categorized under:

Economics > Interactive Decision‐Making

Neuroscience > Cognition

Psychology > Reasoning and Decision Making
Integrating dairy manure for enhanced resource recovery at a WRRF: Environmental life cycle and pilot‐scale analyses
Authors: Bryant Casey , Coats Erik R.
Published: April 2021

The Twin Falls, Idaho wastewater treatment plant (WWTP), currently operates solely to achieve regulatory permit compliance. Research was conducted to evaluate conversion of the WWTP to a water resource recovery facility (WRRF) and to assess the WRRF environmental sustainability; process configurations were evaluated to produce five resources—reclaimed water, biosolids, struvite, biogas, and bioplastics (polyhydroxyalkanoates, PHA). PHA production occurred using fermented dairy manure. State‐of‐the‐art biokinetic modeling, performed using Dynamita's SUMO process model, was coupled with environmental life cycle assessment to quantify environmental sustainability. Results indicate that electricity production via combined heat and power (CHP) was most important in achieving environmental sustainability; energy offset ranged from 43% to 60%, thereby reducing demand for external fossil fuel‐based energy. While struvite production helps maintain a resilient enhanced biological phosphorus removal (EBPR) process, MgO2 production exhibits negative environmental impacts; integration with CHP negates the adverse consequences. Integrating dairy manure to produce bioplastics diversifies the resource recovery portfolio while maintaining WRRF environmental sustainability; pilot‐scale evaluations demonstrated that WRRF effluent quality was not affected by the addition of effluent from PHA production. Collectively, results show that a WRRF integrating dairy manure can yield a diverse portfolio of products while operating in an environmentally sustainable manner.

Practitioner points

Wastewater carbon recovery via anaerobic digestion with combined heat/power production significantly reduces water resource recovery facility (WRRF) environmental emissions.

Wastewater phosphorus recovery is of value; however, struvite production exhibits negative environmental impacts due to MgO2 production emissions.

Bioplastics production on imported organic‐rich agri‐food waste can diversify the WRRF portfolio.

Dairy manure can be successfully integrated into a WRRF for bioplastics production without compromising WRRF performance.

Diversifying the WRRF products portfolio is a strategy to maximize resource recovery from wastewater while concurrently achieving environmental sustainability.
Solution of reactive flow in a rocket engine nozzle with Paraffin/Kerosene propellants
Authors: Nagler Jacob
Published: April 2021

This paper presents a simulation‐based solution for calculating rocket engine performance with liquid‐type propellants of Paraffin and Kerosene for oxidizer to fuel ratio that is given by a linear formula. The engine was divided into two main stages: combustion chamber and a nozzle. In the first phase, conditions were found in the combustion chamber, based on the assumption of equilibrium according to Barrere. Next, the flow in the nozzle was calculated based on the fluid in the combustion chamber. Three main theories were examined in order to find the flow conditions in the nozzle: equilibrium, frozen and mixed flows (Bray conditions). While the latter assumes the existence of the “Sudden Freezing Point” found by Bray, so that from this point to the end of the nozzle, the flow is assumed to be frozen. The use of the proposed simulation might contribute for multiple calculations performance (e.g., fuels with multiple intermediate reactions). Comparison between both types of fuels/propellants for the three described types of flow is presented alongside CEA software results, whereas good agreement between solutions was found. Also, the greater the ratio between hydrogen and carbon atoms, the better the engine performance for a particular oxidizer. Finally, it was found that an equilibrium flow model throughout the nozzle has a better nozzle performance compared to the other types of flows.
Designing Powder Metallurgy Process - The Influence of High Sintering Temperature on Dimensional and Geometrical Precision
Authors: Zago Marco , Cristofolini Ilaria , Amirabdollahian Sasan
Published: April 2021

The precision of parts produced by Powder Metallurgy (PM) strongly depends on the careful design of PM process parameters. Among them, high sintering temperature is generally considered as detrimental for dimensional and geometrical precision, and therefore neglected in industrial production. Nevertheless, high sintering temperature would strongly improve mechanical characteristics of PM parts, so that the real influence of high sintering temperature on dimensional and geometrical precision is of great interest for PM companies. This study investigates the influence of sintering temperature (up to 1350 °C) on dimensional and geometrical precision of real parts. Dimensional changes on sintering and the effect of sintering temperature have been evaluated. Geometrical characteristics have been measured both in the green and in the sintered state, and the real influence of sintering temperature has been highlighted. As a conclusion, it has been demonstrated that the larger shrinkage due to the high sintering temperature is not detrimental with respect to the dimensional precision, being it reliably predictable. Moreover, the influence on geometrical characteristics is unexpectedly low. The encouraging results of this study convinced the main PM companies in Europe to further investigate the influence of high sintering temperature, as partners in a Club Project within the European Powder Metallurgy Association (EPMA).
Cosmological singularities, entanglement and quantum extremal surfaces
Authors: Manu A. , Narayan K. , Paul Partha
Published: April 2021

Abstract

We study aspects of entanglement and extremal surfaces in various families of spacetimes exhibiting cosmological, Big-Crunch, singularities, in particular isotropic AdS Kasner. The classical extremal surface dips into the bulk radial and time directions. Explicitly analysing the extremization equations in the semiclassical region far from the singularity, we find the surface bends in the direction away from the singularity. In the 2-dim cosmologies obtained by dimensional reduction of these and other singularities, we have studied quantum extremal surfaces by extremizing the generalized entropy. The resulting extremization shows the quantum extremal surfaces to always be driven to the semiclassical region far from the singularity. We give some comments and speculations on our analysis.
Evidence for interventions to promote mental health and reduce stigma in Black faith communities: systematic review
Authors: Codjoe Louisa , Barber Sarah , Ahuja Shalini , Thornicroft Graham , Henderson Claire , Lempp Heidi , N’Danga-Koroma Joelyn
Published: April 2021

Purpose

There are significant documented inequalities for the Black community in the UK in relation to mental health care. Research has also indicated that cultural difference exists in pathways into, and engagement with, mental health services. To reduce inequalities and improve engagement with mental health services, it is important that professionals utilise culturally appropriate community networks to increase mental health awareness and reduce stigma. This systematic review considers research in Black faith settings, with two linked aims to review the evidence for the effectiveness of (i) mental health interventions, and (ii) other health stigma interventions as the latter have been implemented in Black faith settings. The review identified ‘active ingredients’ of interventions for this population that can be applied in future work. The authors seek to draw from the mental health and wider health stigma literature to inform the design of the ON TRAC project, a collaborative partnership between King’s College London, South London and Maudsley NHS Foundation Trust and Black faith community groups in Southwark and Lambeth, London, in this currently under-researched area.

Methods

A systematic search of ten major medical and social sciences databases was conducted in 2019, for studies on mental health or other health stigma interventions in Black faith settings. PRISMA guidelines were followed and search terms and search strategy ensured all possible studies were identified for review.

Results

The review identified sixteen studies for inclusion. Ten were quantitative studies, four qualitative studies and two systematic reviews. Active ingredients of interventions included utilisation of ‘bottom up’ development of approaches and mental health champions. Multiple factors were found to influence effective implementation. Co-production and partnership working are key to ensure that an acceptable and accessible intervention is agreed.

Conclusion

Evidence for the effectiveness of interventions focused on mental health awareness and stigma reduction in the Black faith community is limited due to the low quality of studies. This review sheds light on the lessons learnt and necessary key requirements for interventions that can guide future projects.

Study registration: PROSPERO registration number: CRD42018110068
Correction to: Acute ACL reconstruction shows superior clinical results and can be performed safely without an increased risk of developing arthrofibrosis
Authors: von Essen Christoffer , Eriksson Karl , Barenius Björn
Published: April 2021

In the article entitled ‘Acute ACL reconstruction shows superior clinical results and can be performed safely without an increased risk of developing arthrofibrosis’ (Knee Surg Sports Traumatol Arthrosc
Utility of pT3 substaging in lymph node-negative urothelial carcinoma of the bladder: do pathologic parameters add to prognostic sub-stratification?
Authors: Maas Moritz , Mischinger Johannes , Compérat Eva , Scharpf Marcus , Fend Falko , Todenhöfer Tilman , Stenzl Arnulf , Gakis Georgios , Rausch Steffen
Published: April 2021

Purpose

The value of bladder cancer (BC) substaging into macroscopic (pT3b) and microscopic (pT3a) perivesical fat extension in lymph node (Ln)-negative patients is controversially discussed and limited evidence for prognostic relevance of additional histopathological factors in pT3 BC exists. We evaluated the prognostic value of pT3 substaging and established pathological and clinical parameters with focus on tumor invasive front (TIF) and tumor size.

Methods

Specimens of 52 patients treated with radical cystectomy (RC) for pT3 a/b muscle-invasive BC were reviewed and re-evaluated by a pathologist specialized in uropathology. Clinical variables and standard histopathologic characteristics were assessed including TIF and tumor size. Their value as prognosticators for overall survival (OS) and recurrence-free survival (RFS) was evaluated.

Results

Mean age of patients was 67.55 years. Tumors were staged pT3a in 28 patients (53.8%) and pT3b in 24 (46.8%). Median OS was 34.51 months. Median tumor size was 3.2 cm, median TIF was 11.0 mm. Differences in OS between pT3a and pT3b were not significant (p = 0.45). Carcinoma in situ (CIS) and lymphovascular invasion (LVI) were significantly associated with pT3b tumors. Univariate analysis could not identify pathological prognosticators like TIF or tumor size for OS and RFS (p for all > 0.05).

Conclusion

No significant differences in OS or RFS were observed comparing Ln-negative pT3 BC following radical cystectomy. Additional pathologic variables like TIF could not be identified as prognosticator. Relevance of pT3 BC substaging needs reevaluation in larger prospective cohorts.
Hearing loss among elderly people and access to hearing aids: a cross-sectional study from a rural area in Germany
Authors: Didczuneit-Sandhop Birgit , Jóźwiak Katarzyna , Jolie Manja , Holdys Josefine , Hauptmann Michael
Published: April 2021

Purpose

Hearing loss is common and associated with reduced quality of life, particularly among elderly people. However, many patients do not use hearing aids. We evaluated the use of hearing aids among people with hearing loss by health services availability near their residence in a rural area in the state of Brandenburg, Germany.

Methods

Audiometry was performed in a convenience sample of subjects in ten towns and hearing loss was determined, defined as a threshold of ≥ 30 dB in at least one ear and at least one of the frequencies 0.5, 1.0, 2.0 and 4.0 kHz. For each participant, age and gender were collected and whether or not hearing aids were available.

Results

Among 186 persons with an average age of 74 years (interquartile range 71–81), 97% had hearing loss [95% confidence interval (CI) 95–100]. Among 121 patients with hearing loss who reported whether or not they have a hearing aid, 93 had no hearing aid (77%, 95% CI 69–84). The proportion of hearing-impaired persons who do not have a hearing aid significantly increased with the absence of a hearing aid specialist or ear nose throat (ENT) physician or both in the town where the tests were performed (p trend = 0.001).

Conclusion

Hearing loss is common among elderly people in the study area and many people in rural areas in Germany may not be properly supplied with hearing aids due to lack of hearing aid specialists and/or ENT physicians close to their residence. Interventions to improve this situation are urgently required.
Morphological changes during the post-embryonic ontogeny of mesothelan spiders and aspects of character evolution in early spiders
Authors: Huber Thomas , Haug Carolin
Published: April 2021

Most morphological studies focus on adult specimens, or if developmental studies are pursued, especially in Euarthropoda, they focus on embryonic development. Araneae (spiders) is one of these groups, in consequence with understudied post-embryonic development. Here we present aspects of the post-embryonic stages of different species of Mesothelae, sister group to the remaining spiders (when fossil species are not taken into account). We used different imaging methods and measured different external morphological structures to detect possible ontogenetic changes. One structure exhibiting post-embryonic changes is the chelicera. Here the significant change occurs between the last immature stage and the adult, yet only in males. For the spinnerets, we could not detect ontogenetic changes, but instead a high variability in length and width, probably due to their lack of pivot joints between the elements. The strongest morphological change during ontogeny occurred on the sternum, which begins with a rather roundish shape in the first stage and changes to being fairly elongate in shape in the last immature stages and the adult. This specific sternum shape only occurs in adults of mesothelan spiders, while opisthothelan spiders have a broader sternum also in the adult. We discuss our results in an evolutionary context, also taking into account recent finds of fossil spiders.
A novel hybrid PSO-based metaheuristic for costly portfolio selection problems
Authors: Corazza Marco , di Tollo Giacomo , Fasano Giovanni , Pesenti Raffaele
Published: April 2021

In this paper we propose a hybrid metaheuristic based on Particle Swarm Optimization, which we tailor on a portfolio selection problem. To motivate and apply our hybrid metaheuristic, we reformulate the portfolio selection problem as an unconstrained problem, by means of penalty functions in the framework of the exact penalty methods. Our metaheuristic is hybrid as it adaptively updates the penalty parameters of the unconstrained model during the optimization process. In addition, it iteratively refines its solutions to reduce possible infeasibilities. We report also a numerical case study. Our hybrid metaheuristic appears to perform better than the corresponding Particle Swarm Optimization solver with constant penalty parameters. It performs similarly to two corresponding Particle Swarm Optimization solvers with penalty parameters respectively determined by a REVAC-based tuning procedure and an irace-based one, but on average it just needs less than 4% of the computational time requested by the latter procedures.
Neuroanatomical Correlates of Social Intelligence Measured by the Guilford Test
Authors: Myznikov A. , Zheltyakova M. , Korotkov A. , Kireev M. , Masharipov R. , Jagmurov O. Dz. , Habel U. , Votinov M.
Published: April 2021

Social interactions are a crucial aspect of human behaviour. Numerous neurophysiological studies have focused on socio-cognitive processes associated with the so-called theory of mind—the ability to attribute mental states to oneself and others. Theory of mind is closely related to social intelligence defined as a set of abilities that facilitate effective social interactions. Social intelligence encompasses multiple theory of mind components and can be measured by the Four Factor Test of Social Intelligence (the Guilford-Sullivan test). However, it is unclear whether the differences in social intelligence are reflected in structural brain differences. During the experiment, 48 healthy right-handed individuals completed the Guilford-Sullivan test. T1-weighted structural MRI images were obtained for all participants. Voxel-based morphometry analysis was performed to reveal grey matter volume differences between the two groups (24 subjects in each)—with high social intelligence scores and with low social intelligence scores, respectively. Participants with high social intelligence scores had larger grey matter volumes of the bilateral caudate. The obtained results suggest the caudate nucleus involvement in the neural system of socio-cognitive processes, reflected by its structural characteristics.
Accessibility of fiber surface sites for polymeric additives determines dry and wet tensile strength of paper sheets
Authors: Schäfer J.-L. , Schölch S. , Prucker O. , Brandstetter T. , Rühe J. , Stockert A. Ritter v. , Meckel T. , Biesalski M.
Published: April 2021

This contribution focuses on understanding of paper wet-strength properties, by taking a closer look at the spatial distribution of wet-strengthening polymers inside the cellulosic fiber network deposited under different treatment conditions using confocal laser scanning microscopy as in situ imaging tool. We compare the behavior of paper samples treated with a photochemically cross-linkable copolymer using an impregnation process employing three different solvents, namely water, 2-propanol (IPA) and 1-butanol (BuOH), respectively. As these solvents swell paper fibers to quite different extents, the deposition of the polymer, on, in or in-between the cellulosic fibers varies quite strongly, as is shown by in-depth analysis using confocal laser scanning microscopy. The difference in accessibility of distinct surface sites exclusively on or also in and between the fibers controls the macroscopic tensile strength under both dry and wet conditions.
Regional Coronavirus Hotspots During the COVID-19 Outbreak in the Netherlands
Authors: Hassink Wolter H. J. , Kalb Guyonne , Meekes Jordy
Published: April 2021

We explore the impact of COVID-19 hotspots and regional lockdowns on the Dutch labour market during the outbreak of COVID-19. Using weekly administrative panel microdata for 50 per cent of Dutch employees until the end of March 2020, we study whether individual labour market outcomes, as measured by employment, working hours and hourly wages, were more strongly affected in provinces where COVID-19 confirmed cases, hospitalizations and mortality were relatively high. The evidence suggests that labour market outcomes were negatively affected in all regions and local higher virus case numbers did not reinforce this decline. This suggests that preventive health measures should be at the regional level, isolating hotspots from low-risk areas.
A first look at Android applications in Google Play related to COVID-19
Authors: Samhi Jordan , Allix Kevin , Bissyandé Tegawendé F. , Klein Jacques
Published: April 2021

Due to the convenience of access-on-demand to information and business solutions, mobile apps have become an important asset in the digital world. In the context of the COVID-19 pandemic, app developers have joined the response effort in various ways by releasing apps that target different user bases (e.g., all citizens or journalists), offer different services (e.g., location tracking or diagnostic-aid), provide generic or specialized information, etc. While many apps have raised some concerns by spreading misinformation or even malware, the literature does not yet provide a clear landscape of the different apps that were developed. In this study, we focus on the Android ecosystem and investigate Covid-related Android apps. In a best-effort scenario, we attempt to systematically identify all relevant apps and study their characteristics with the objective to provide a first taxonomy of Covid-related apps, broadening the relevance beyond the implementation of contact tracing. Overall, our study yields a number of empirical insights that contribute to enlarge the knowledge on Covid-related apps: (1) Developer communities contributed rapidly to the COVID-19, with dedicated apps released as early as January 2020; (2) Covid-related apps deliver digital tools to users (e.g., health diaries), serve to broadcast information to users (e.g., spread statistics), and collect data from users (e.g., for tracing); (3) Covid-related apps are less complex than standard apps; (4) they generally do not seem to leak sensitive data; (5) in the majority of cases, Covid-related apps are released by entities with past experience on the market, mostly official government entities or public health organizations.