bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of approximations in analyses of beams of open thin‐walled cross‐section—part I: Flexural–torsional stability
Authors: Pi Y.‐L. , Bradford M. A.
Published: November 2023

In formulating a finite element model for the flexural–torsional stability and 3‐D non‐linear analyses of thin‐walled beams, a rotation matrix is usually used to obtain the non‐linear strain–displacement relationships. Because of the coupling between displacements, twist rotations and their derivatives, the components of the rotation matrix are both lengthy and complicated. To facilitate the formulation, approximations have been used to simplify the rotation matrix. A simplified small rotation matrix is often used in the formulation of finite element models for the flexural–torsional stability analysis of thin‐walled beams of open cross‐section. However, the approximations in the small rotation matrix may lead to the loss of some significant terms in the stability stiffness matrix. Without these terms, a finite element line model may predict the incorrect flexural–torsional buckling load of a beam. This paper investigates the effects of approximations in the elastic flexural–torsional stability analysis of thin‐walled beams, while a companion paper investigates the effects of approximations in the 3‐D non‐linear analysis. It is found that a finite element line model based on a small rotation matrix may predict incorrect elastic flexural–torsional buckling loads of beams. To perform a correct flexural–torsional stability analysis of thin‐walled beams, modification of the model is needed, or a finite element model based on a second‐order rotation matrix can be used. Copyright © 2001 John Wiley & Sons, Ltd.
On topology optimization of plates with prestress
Authors: Pedersen Niels L.
Published: November 2023

In this work, topology optimization is used to optimize the compliance or eigenvalues of prestressed plates. The prestress is accounted for by including the force equivalent to the prestressing and adding the initial stress stiffness matrix to the original stiffness matrix. The calculation of the sensitivities is complicated because of the initial stress stiffness matrix, but the computational cost can be kept low by using the adjoint method. The topology optimization problem is solved using the solid isotropic material with penalization (SIMP) method in combination with method of moving asymptotes (MMA). Numerical examples of minimizing compliance or maximizing the first eigenvalue of plates are given. One example is a micro electro mechanical systems (MEMS) application involving a backplate used in a microphone in a hearing aid. Copyright © 2001 John Wiley & Sons, Ltd.
Fully C1‐conforming subdivision elements for finite deformation thin‐shell analysis
Authors: Cirak Fehmi , Ortiz Michael
Published: November 2023

We have extended the subdivision shell elements of Cirak et al. [18] to the finite‐deformation range. The assumed finite‐deformation kinematics allows for finite membrane and thickness stretching, as well as for large deflections and bending strains. The interpolation of the undeformed and deformed surfaces of the shell is accomplished through the use of subdivision surfaces. The resulting ‘subdivision elements’ are strictly C1‐conforming, contain three nodes and one single quadrature point per element, and carry displacements at the nodes only. The versatility and good performance of the subdivision elements is demonstrated with the aid of a number of test cases, including the stretching of a tension strip; the inflation of a spherical shell under internal pressure; the bending and inflation of a circular plate under the action of uniform pressure; and the inflation of square and circular airbags. In particular, the airbag solutions, while exhibiting intricate folding patterns, appear to converge in certain salient features of the solution, which attests to the robustness of the method. Copyright © 2001 John Wiley & Sons, Ltd.
Buckling behavior and energy absorption of grid‐stiffened composite cylinders under low‐velocity axial impact
Authors: Yazdani Mojtaba , Sharifloo Shabnam , Rezaei Mohammad
Published: November 2023

Grid‐stiffened composite cylinders are widely used in a variety of applications and are subjected to static, dynamic, and impact loads. In terms of buckling strength, these structures outperform simple layered and sandwich composites of the same weight, and the presence of unidirectional fiber ribs contributes to their delamination resistance. The purpose of this research is to look into the buckling behavior of grid‐stiffened composite cylinders under low‐velocity and high‐energy axial impacts. The tests were carried out at room temperature using a 35 kg impactor with an impactor fall height of about 2.75 m. This study builds on previous research and considers the samples' thin skin, indicating that skin buckling is the primary buckling mode in such scenarios. According to static loading research, three types of buckling can occur in grid‐stiffened composite cylinders: local shell buckling, local rib buckling, and general buckling, and each of these can be controlled by adjusting the geometric properties. But, based on the loading speed in the weight‐drop test, controlling the specific type of buckling that occurs during impact loading is difficult. Examining residual structural effects can help determine the type of buckling and damage sustained during impact events. According to the results, the forces that cause buckling in grid‐stiffened composite structures under impact loads are 1.5–2 times greater than static loading conditions. Notably, once the forces are removed, these structures can return to their original positions, however with less stiffness. As a result, they absorb a significant amount of impact energy.

Highlights

Composite cylinders with spiral ribs have higher static compression resistance.

Dynamic loading increases local buckling forces in grid‐stiffened structures.

Despite being damaged, grid‐stiffened cylinders bounce back quickly after impact.

Skin buckling is a common mode of failure for grid‐stiffened composite.

The global buckling force is greater than the local buckling force.
Radiographically occult congenital lobar emphysema presenting as unexplained neonatal tachypnea
Authors: Rusakow Lee S. , Khare Smriti
Published: November 2023

Congenital lobar emphysema (CLE) is usually diagnosed in the newborn period in an infant with respiratory difficulties and classic X‐ray film findings. We describe a neonate with tachypnea of unclear etiology who was diagnosed with CLE by chest computed tomography scan, despite a plain chest radiograph that did not suggest the diagnosis. Pediatr Pulmonol. 2001; 32:246–249. © 2001 Wiley‐Liss, Inc.
Stimulation of lung growth in fetuses with lung hypoplasia leads to altered postnatal lung structure in sheep
Authors: Davey M.G. , Hooper S.B. , Cock M.L. , Harding R.
Published: November 2023

Increased lung expansion in the fetus stimulates lung growth and is being trialed clinically to reverse severe fetal lung hypoplasia. Our aim was to examine the effects of increased fetal lung expansion in the presence of lung hypoplasia on lung structure in sheep at term and 8 weeks after birth. Lung hypoplasia was induced in 15 fetal sheep by continuous drainage of tracheal fluid, commencing at ∼113 days of gestation (term, ∼148 days). In 10 of these fetuses, tracheal obstruction (TO) was performed from 137–147 days of gestation (treated lung hypoplasia, TLH), while lung liquid drainage continued until term in the remaining 5 fetuses (untreated lung hypoplasia, ULH). Lung tissues were obtained from 5 TLH, 5 ULH, and 5 control lambs at birth, and from 5 TLH and 5 control lambs at 8 weeks after birth.

At birth, alveolar number, surface area, and interalveolar wall thickness were not different between TLH and control lambs, whereas airspace diameter was greater in TLH lambs (72.7 ± 3.0 μm) than in controls (58.4 ± 4.3 μm). Diameters of airspaces were not different between ULH and control lambs; however, alveolar numbers and surface area were reduced, while interalveolar wall thickness was increased in ULH lambs compared to controls. At 8 weeks after birth, alveolar number (928.0 ± 66.1 × 106) and surface area (30.3 ± 2.2 m2) in TLH lambs were lower, whereas interalveolar wall thickness (83.0 ± 3.1μm) was greater than in control lambs (2,263.6 ± 261.6 × 106, 46.7 ± 4.8 m2, and 68.6 ± 2.1 μm, respectively).

Our data show that TO restores most aspects of lung structure to normal in fetuses with lung hypoplasia but leads to altered alveolar development. The presence of fewer, larger alveoli in postnatal TLH animals may predispose these animals to respiratory complications during later life. Pediatr Pulmonol. 2001; 32:267–276. © 2001 Wiley‐Liss, Inc.
Acceleration of lung disease in children with cystic fibrosis afterPseudomonas aeruginosaacquisition
Authors: Kosorok Michael R. , Zeng Lan , West Susan E.H. , Rock Michael J. , Splaingard Mark L. , Laxova Anita , Green Christopher G. , Collins Jannette , Farrell Philip M.
Published: November 2023

As part of the ongoing Wisconsin Cystic Fibrosis (CF) Neonatal Screening Project, we had the unique opportunity to study the longitudinal relationship betweenPseudomonas aeruginosa(Pa) acquisition and infection and developing lung disease in children with CF. The primary objective was to determine whether acquisition ofPawas associated with a measurable change in the progression of lung disease. Two outcome measures were used to study 56 patients who were diagnosed through newborn screening: 1) Wisconsin additive chest radiograph score (WCXR), based on the average of scores from a pulmonologist and a radiologist, and 2) the highest forced expired volume in 1 sec (FEV1)/forced vital capacity (FVC) ratio. We used two measures ofPaacquisition: 1) time of first positive protocol‐determined oropharyngeal (with cough) culture, and 2) the magnitude of antibody titer detected by ELISA assays, using as antigen a crude cell lysate, purified exotoxin A, or an elastase toxoid prepared from threePastrains. Other predictor variables included age, pancreatic status, height‐for age, and weight‐for‐age‐percentiles.

The best regression model for predicting changes in the WCXR included time to first positive culture and antibody titer forPaelastase. Prior toPaacquisition, WCXR worsened by 0.45 points/year (P > 0.25); afterPaacquisition, the rate of worsening increased significantly (P < 0.001) to 1.40 points/year. Each antibody titer level (log base 2) increased the score by 0.48 points (P < 0.001). The best regression model for predicting change in the FEV1/FVC included only time to first positive culture. Prior toPaacquisition, the FEV1/FVC ratio declined by 1.29%/year; afterPainfection, the rate of decrease significantly accelerated to 1.81%/year (P = 0.001).

Our data show thatPaacquisition is associated with declining pulmonary status in children with CF, and that this effect is probably gradual rather than precipitous. Because these patients were diagnosed and treated aggressively, our estimates of the effects ofPaacquisition may be conservative. We also conclude that the WCXR appears to be more sensitive than FEV1/FVC in detecting early changes in lung disease associated with CF. Pediatr Pulmonol. 2001; 32:277–287. © 2001 Wiley‐Liss, Inc.
Orthogonal determinants of $${\textrm{SL}\,}_3(q)$$ and $${\textrm{SU}\,}_3(q)$$
Authors: Hoyer Linda , Nebe Gabriele
Published: November 2023

We give a full list of the orthogonal determinants of the even degree indicator ‘+’ ordinary irreducible characters of$$\textrm{SL}_3(q)$$SL3(q)and$$\textrm{SU}_3(q)$$SU3(q).
A short note on coproducts of Abelian pro-Lie groups
Authors: Herfort Wolfgang , Hofmann Karl H. , Russo Francesco G.
Published: November 2023

The notion of conditional coproduct of a family of abelian pro-Lie groups in the category of abelian pro-Lie groups is introduced. It is shown that the cartesian product of an arbitrary family of abelian pro-Lie groups can be characterized by the universal property of the conditional coproduct.
Prognostic value of flow-status in severe aortic stenosis patients undergoing percutaneous intervention
Authors: Santos-Ferreira Diogo , Fernandes Isabel , Diaz Sílvia O. , Guerreiro Cláudio , Saraiva Francisca , Barros António S. , Leite-Moreira Adelino , Pereira Eulália , Sampaio Francisco , Ribeiro José , Braga Pedro , Fontes-Carvalho Ricardo
Published: November 2023

Purpose

Low-flow status is a mortality predictor in severe aortic stenosis (SAS) patients, including after transcatheter aortic valve implantation (TAVI) treatment. However, the best parameter to assess flow is unknown. Recent studies suggest that transaortic flow rate (FR) is superior to currently used stroke volume index (SVi) in defining low-flow states. Therefore, we aimed to evaluate the prognostic value of FR and SVi in patients undergoing TAVI.

Methods

A single-centre retrospective analysis of all consecutive patients treated with TAVI for SAS between 2011 and 2019 was conducted. Low-FR was defined as < 200 mL/s and low-SVi as < 35 mL/m2. Primary endpoint was all-cause five-year mortality, analyzed using Kaplan-Meier curves and Cox regression models. Secondary endpoint was variation of NYHA functional class six months after procedure. Patients were further stratified according to ejection fraction (EF < 50%).

Results

Of 489 cases, 59.5% were low-FR, and 43.1% low-SVi. Low-flow patients had superior surgical risk, worse renal function, and had a higher prevalence of coronary artery disease. Low-FR was associated with mortality (hazard ratio 1.36, p = 0.041), but not after adjustment to EuroSCORE II. Normal-SVi was not associated with survival, despite a significative p-trend for its continuous value. No associations were found for flow-status and NYHA recovery. When stratifying according to preserved and reduced EF, both FR and SVi did not predict all-cause mortality.

Conclusion

In patients with SAS undergoing TAVI, a low-FR state was associated with higher mortality, as well as SVi, but not at a 35 mL/m2 cut off.
Three-membered ring formation catalyzed by α-ketoglutarate-dependent nonheme iron enzymes
Authors: Ushimaru Richiro
Published: November 2023

Epoxides, aziridines, and cyclopropanes are found in various medicinal natural products, including polyketides, terpenes, peptides, and alkaloids. Many classes of biosynthetic enzymes are involved in constructing these ring structures during their biosynthesis. This review summarizes our current knowledge regarding how α-ketoglutarate-dependent nonheme iron enzymes catalyze the formation of epoxides, aziridines, and cyclopropanes in nature, with a focus on enzyme mechanisms.
IDO-1 impairs antitumor immunity of natural killer cells in triple-negative breast cancer via up-regulation of HLA-G
Authors: Jing Rui , Bai Shukun , Zhang Peipei , Ren Hao , Jia Lintao , Li Weimiao , Zheng Guoxu
Published: November 2023

Background

Triple-negative breast cancers (TNBC) are highly aggressive malignancies with poor prognosis. As an essential enzyme in the tryptophan–kynurenine metabolic pathway, indoleamine 2,3 dioxygenase-1 (IDO-1) has been reported to facilitate immune escape of various tumors. However, the mechanism underlying the immunosuppressive role of IDO-1 in TNBC remains largely uncharacterized.

Methods

We examined the IDO-1 expression in 93 clinical TNBC tissues and paired adjacent normal tissues, and analyzed the regulation role of environmental cytokines like IFN-γ in IDO-1 expression. The effect of IDO-1 expression in TNBC cells on the function of NK cells were then evaluated and the underlying mechanisms were exploited.

Results

IDO-1 expressed in 50 of 93 (54.1%) TNBC patients. TNBC patients with high IDO-1 expression tended to have more infiltrated immune cells including NK cells, which are less active than patients with low IDO-1 expression. NK cells could produce IFN-γ, which induced IDO-1 expression in TNBC cells, whereas IDO-1 impaired the cytotoxicity of co-cultured NK cells by upregulation of HLA-G. Blockade of HLA-G improved the antitumor activity of NK cells to TNBC in vivo.

Conclusion

TNBC cells induce dysfunction of NK cells through an IFN-γ/IDO-1/HLA-G pathway, which provide novel insights into the mechanisms of TNBC progression and demonstrate the applicability of IDO-1 and HLA-G targeting in the treatment of TNBC.
A comprehensive analysis of SLC25A1 expression and its oncogenic role in pan-cancer
Authors: You Xin , Huang Lingling , Huang Ouxiang , Deng Yujie , Shi Xi
Published: November 2023

Objective

The solute carrier family 25 member 1 (SLC25A1) is currently the only known human transporter for citrate in the mitochondrial membrane. However, its role in cancer development remains to be elucidated. We aim to analyze the expression profile, prognostic value, potential immunological significance, and effect on tumor growth of SLC25A1 at a pan-cancer level.

Methods

Herein, the role of SLC25A1 in tumorigenesis and progression was investigated based on the Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), Genotype-Tissue Expression (GTEx), Clinical Proteomic Tumor Analysis Consortium (CPTAC), GeneMANIA, STRING and Cancer Dependency Map Project (DepMap) database via online websites or the R software. The protein expression levels were validated in tissue microarrays, and the effects on tumor cell lines were accessed through MTS and colony formation assays.

Results

The expression of SLC25A1 increased in most cancers, and the upregulation of SLC25A1 in colon adenocarcinoma and lung adenocarcinoma was further confirmed by immunohistochemistry. Meanwhile, SLC25A1 was linked to clinical outcomes across multiple tumor types, particularly in lung adenocarcinoma, where its high expression predicted poor prognosis. Moreover, SLC25A1 was positively associated with MSI, TMB, and CD276 and tightly correlated with tumor-infiltrating immune cells. Furthermore, the knockout of SLC25A1 demonstrated inhibitory effects in most cancer cell lines in the DepMap project. Cellular experiments showed that SLC25A1 knockdown significantly reduced the proliferation of lung adenocarcinoma cells.

Conclusions

Our findings suggest the potential of SLC25A1 as a prognostic biomarker for cancers and a therapeutic target for precise antitumor strategy and cancer immunotherapy.
Sedimentary abundance and major determinants of river microplastic contamination in the central arid part of Iran
Authors: Behmanesh Mokarrameh , Chamani Atefeh , Chavoshi Elham
Published: November 2023

The proliferation of anthropogenic activities around the Central Iranian Rivers shows a warning alarm of river microplastic (MP) pollution. In the Zayandeh-rood River, the mean abundance of sedimentary MPs trapped at the mouth of 21 modified sub-catchments was 588 items/kg d.w and followed the order: downstream (1701 items/kg d.w) > midstream (269.2 items/kg d.w) > upstream (57.2 items/kg d.w). The widespread distribution of fiber and fragment forms across all stations and the high MP abundance near the discharge of the largest wastewater treatment plant indicate their origin from both point and non-point sources. Using the linear multiple linear regression (MLR) and nonlinear artificial neural network (ANN), we assessed the contribution of three types of variables including the sediment physio-chemical properties, river geometry and land-use characteristics. According to both modeling results, the mean annual number of local people and tourist visitors (0.35 million people) are the most important determinants of river MP pollution whose contribution dominates through the use of plastic products and their direct and indirect release into the environment. The ANN model (R2 = 0.99) outperformed the MLR model (R2 = 0.80) and showed the importance of total organic carbon (TOC)-rich regions as MP hotspots. To alleviate the river MP pollution, suggested measures involve altering plastic usage and disposal practices among visitors and reducing the TOC content in the industrial/municipal wastewater entering the river.
Coupling of Adhesion and Anti-Freezing Properties in Hydrogel Electrolytes for Low-Temperature Aqueous-Based Hybrid Capacitors
Authors: Nan Jingya , Sun Yue , Yang Fusheng , Zhang Yijing , Li Yuxi , Wang Zihao , Wang Chuchu , Wang Dingkun , Chu Fuxiang , Wang Chunpeng , Zhu Tianyu , Jiang Jianchun
Published: November 2023

Solid-state zinc-ion capacitors are emerging as promising candidates for large-scale energy storage owing to improved safety, mechanical and thermal stability and easy-to-direct stacking. Hydrogel electrolytes are appealing solid-state electrolytes because of eco-friendliness, high conductivity and intrinsic flexibility. However, the electrolyte/electrode interfacial contact and anti-freezing properties of current hydrogel electrolytes are still challenging for practical applications of zinc-ion capacitors. Here, we report a class of hydrogel electrolytes that couple high interfacial adhesion and anti-freezing performance. The synergy of tough hydrogel matrix and chemical anchorage enables a well-adhered interface between hydrogel electrolyte and electrode. Meanwhile, the cooperative solvation of ZnCl2 and LiCl hybrid salts renders the hydrogel electrolyte high ionic conductivity and mechanical elasticity simultaneously at low temperatures. More significantly, the Zn||carbon nanotubes hybrid capacitor based on this hydrogel electrolyte exhibits low-temperature capacitive performance, delivering high-energy density of 39 Wh kg−1 at −60 °C with capacity retention of 98.7% over 10,000 cycles. With the benefits of the well-adhered electrolyte/electrode interface and the anti-freezing hydrogel electrolyte, the Zn/Li hybrid capacitor is able to accommodate dynamic deformations and function well under 1000 tension cycles even at −60 °C. This work provides a powerful strategy for enabling stable operation of low-temperature zinc-ion capacitors.
Ndiku Mutua, et al. v The Foreign and Commonwealth Office
Authors: Gulecha Anmol
Published: November 2023

In 2009 five Kenyans filed a tort action seeking damages against the Foreign and Commonwealth Office (the FCO), a department of the United Kingdom (the UK), for abuse suffered in Kenyan detention camps during the colonial period. While the FCO denied liability, the claimants produced historical evidence from three academic historians to dispute the FCO’s stand. With both sides unable to agree on the FCO’s liability, the Court, as a non-expert in historical research, was called to pass judgment. In light of this contested liability, this case note shows that when historians, who are ‘experts’ in their field, present evidence to the Court, the latter is better equipped to understand the liability of the FCO, and by extension the UK Government, for colonial-era crimes.
Integrating the gender dimension to disclose the degree of businesses’ articulation of innovation
Authors: di Tollo Giacomo , Andria Joseph , Tanev Stoyan , Ghilardi Sara
Published: November 2023

In this contribution, we examine the relationship between the presence of women in companies’ Boards and innovation communication claims: we propose a framework to quantitatively assess the presence of women and the online articulation of innovation, in order to understand whether some correlations hold between these two variables. We also introduce a neural network approach to predict the innovation metric that uses, amongst the predictors, the gender component, and we compare it with a linear regression analysis. Results indicate that neural networks may be used to predict the articulation of innovation by using a predictor set that includes the gender component of the Board of Directors, and also that the use of the gender metric improves previous predictions about the articulation of innovation model’s output.
Reactive response to predation risk affects foraging time of hares, yet not their phosphorus intake
Authors: Brandsen Samara , Vermorken Louise S. , Kuipers Henry J. , van Wieren Sip E. , de Jonge Inger K. , Weterings Martijn J. A.
Published: November 2023

Antipredator responses could affect nutrient intake, which could lead to nutritional deficits. However, little is known about the antipredator response of small herbivores because most are nocturnal or crepuscular and therefore very difficult to study in the field. Therefore, we experimentally assessed the effect of a reactive response to predation risk on the nutrient (i.e., phosphorous) intake of the European hare (Lepus europaeus) using three different playback sounds. Additionally, we studied the time spent being costly vigilant, the time spent foraging, and the vegetation height in which the hares were present using accelerometers and GPS. Our results showed that elevated predation risk from our playback experiment did not affect the (1) phosphorus intake, (2) time spent being costly vigilant, and (3) time spent in tall vegetation. However, elevated predation risk did increase the time spent foraging. Possibly hares spent more time foraging with an increased predation risk because hares cannot seek refuge from predators. Additionally, the effect on phosphorus intake could be weak because phosphorous intake does not benefit a flight escape, while the reactive response acts late in the predation sequence limiting the effect on hare ecology. Prey anti-predator responses seem strongly related to the escape tactics of prey species that can differ between different habitats and the time of the day. More detailed field studies are necessary to get a better insight into species’ anti-predator-food tactics.
PEEK Interference Screws Show Significant Tunnel Enlargement After ACL Reconstruction and is Comparable to Adjustable-Length Loop Cortical Button Fixation
Authors: Coppola Christian , Krost Sandra , Runer Armin , Raas Christoph , Glodny Bernhard , Mayr Raul
Published: November 2023

Background

It is unclear whether the use of polyetheretherketone (PEEK) interference screws for anterior cruciate ligament (ACL) reconstruction leads to postoperative tunnel enlargement. Femoral tunnel enlargement was further compared with adjustable-length loop cortical fixation.

Methods

Eighteen patients with ACL reconstruction using hamstring grafts were retrospectively divided into two groups. Eleven patients were treated with the ACL reconstruction technique using a PEEK interference screw for femoral graft fixation. Seven patients received adjustable-length loop cortical buttons for femoral fixation. Tibial ACL graft fixation was performed using PEEK interference screws. Tunnel volume changes were assessed using computed tomography (CT) scans performed after surgery (100%) and after 1 year. The maximal tunnel diameter was measured.

Results

The group with femoral screw fixation showed a mean tunnel volume change of 108.15 ± 13.7% on the tibial side and 124.07 ± 25.38% on the femoral side. The group with femoral button fixation showed a tunnel volume change of 111.12 ± 12.72% on the tibial side and 130.96 ± 21.71% on the femoral side. The differences in femoral tunnel volume changes were not significant (P = 0.562). Femoral tunnels with PEEK screw fixation showed significantly larger diameter after 12 months in comparison with button fixation (13.02 ± 1.43 mm vs. 10.46 ± 1.29 mm, P < 0.001).

Conclusions

PEEK interference screws were associated with significant tibial and femoral tunnel enlargement. Femoral tunnel enlargement was comparable between PEEK interference screws and button fixation. Final femoral tunnel diameter was significantly larger with PEEK screw fixation in comparison to button fixation.
Internet of things (IoT)-based on real-time and remote boiler fuel monitoring system: a case of Raha Beverages Company Limited, Arusha-Tanzania
Authors: Ntambara Boniface , Nyambo Devotha G. , Solsbach Andreas
Published: November 2023

RAHA Beverages Company (RABEC) is one of the banana wine production companies that utilizes fuel in steam production in Arusha-Tanzania, where fuel data conditions such as temperature, pressure, discharge, fuel level, and gas leakage with humidity were a challenge to monitor, which provoked boiler malfunction and plant breakdown. Today, RABEC manually uses a dropping stick into the fuel tank to monitor fuel data conditions which is time-consuming and gives inaccurate readings, inefficiency, fuel economy discrepancy, and accidents. This study aimed to design and develop an IoT-based fuel monitoring system. The flow meter, ultrasonic level, thermistor fuel temperature, humidity, and pressure sensors were used to gather fuel information where the GSM module was employed to send fuel data messages to the operator’s phone. An AT mega 328 microcontroller was used to process and analyse the fuel data and send them to the Thing Speak IoT platform using Wi-Fi connectivity. The results showed that when the fuel level was less than the threshold value, an operator was alerted by a refilling message via GSM technology. A pressure of 0.1psi, a fuel temperature of 120 ℃, and 80% of humidity, the system notifies the operator by an alert message to check the injector pressure and if the fuel–air mixture is perfect. In addition, these data were observed on the LCD and ThingSpeak webpage. To conclude, the developed system proved the best performance with a 99.98% of success rate with high accuracy, security, and efficiency rate compared to the current monitoring system.
Direct imaging of electron density with a scanning transmission electron microscope
Authors: Dyck Ondrej , Almutlaq Jawaher , Lingerfelt David , Swett Jacob L. , Oxley Mark P. , Huang Bevin , Lupini Andrew R. , Englund Dirk , Jesse Stephen
Published: November 2023

Recent studies of secondary electron (SE) emission in scanning transmission electron microscopes suggest that material’s properties such as electrical conductivity, connectivity, and work function can be probed with atomic scale resolution using a technique known as secondary electron e-beam-induced current (SEEBIC). Here, we apply the SEEBIC imaging technique to a stacked 2D heterostructure device to reveal the spatially resolved electron density of an encapsulated WSe2 layer. We find that the double Se lattice site shows higher emission than the W site, which is at odds with first-principles modelling of valence ionization of an isolated WSe2 cluster. These results illustrate that atomic level SEEBIC contrast within a single material is possible and that an enhanced understanding of atomic scale SE emission is required to account for the observed contrast. In turn, this suggests that, in the future, subtle information about interlayer bonding and the effect on electron orbitals could be directly revealed with this technique.
Mott insulators with boundary zeros
Authors: Wagner N. , Crippa L. , Amaricci A. , Hansmann P. , Klett M. , König E. J. , Schäfer T. , Sante D. Di , Cano J. , Millis A. J. , Georges A. , Sangiovanni G.
Published: November 2023

The topological classification of electronic band structures is based on symmetry properties of Bloch eigenstates of single-particle Hamiltonians. In parallel, topological field theory has opened the doors to the formulation and characterization of non-trivial phases of matter driven by strong electron-electron interaction. Even though important examples of topological Mott insulators have been constructed, the relevance of the underlying non-interacting band topology to the physics of the Mott phase has remained unexplored. Here, we show that the momentum structure of the Green’s function zeros defining the “Luttinger surface" provides a topological characterization of the Mott phase related, in the simplest description, to the one of the single-particle electronic dispersion. Considerations on the zeros lead to the prediction of new phenomena: a topological Mott insulator with an inverted gap for the bulk zeros must possess gapless zeros at the boundary, which behave as a form of “topological antimatter” annihilating conventional edge states. Placing band and Mott topological insulators in contact produces distinctive observable signatures at the interface, revealing the otherwise spectroscopically elusive Green’s function zeros.
Self-carbon-thermal-reduction strategy for boosting the Fenton-like activity of single Fe-N4 sites by carbon-defect engineering
Authors: Wei Shengjie , Sun Yibing , Qiu Yun-Ze , Li Ang , Chiang Ching-Yu , Xiao Hai , Qian Jieshu , Li Yadong
Published: November 2023

Carbon-defect engineering in metal single-atom catalysts by simple and robust strategy, boosting their catalytic activity, and revealing the carbon defect-catalytic activity relationship are meaningful but challenging. Herein, we report a facile self-carbon-thermal-reduction strategy for carbon-defect engineering of single Fe-N4 sites in ZnO-Carbon nano-reactor, as efficient catalyst in Fenton-like reaction for degradation of phenol. The carbon vacancies are easily constructed adjacent to single Fe-N4 sites during synthesis, facilitating the formation of C-O bonding and lowering the energy barrier of rate-determining-step during degradation of phenol. Consequently, the catalyst Fe-NCv-900 with carbon vacancies exhibits a much improved activity than the Fe-NC-900 without abundant carbon vacancies, with 13.5 times improvement in the first-order rate constant of phenol degradation. The Fe-NCv-900 shows high activity (97% removal ratio of phenol in only 5 min), good recyclability and the wide-ranging pH universality (pH range 3-9). This work not only provides a rational strategy for improving the Fenton-like activity of metal single-atom catalysts, but also deepens the fundamental understanding on how periphery carbon environment affects the property and performance of metal-N4 sites.
Mobilization of endocannabinoids by midbrain dopamine neurons is required for the encoding of reward prediction
Authors: Luján Miguel Á. , Covey Dan P. , Young-Morrison Reana , Zhang LanYuan , Kim Andrew , Morgado Fiorella , Patel Sachin , Bass Caroline E. , Paladini Carlos , Cheer Joseph F.
Published: November 2023

Brain levels of the endocannabinoid 2-arachidonoylglycerol (2-AG) shape motivated behavior and nucleus accumbens (NAc) dopamine release. However, it is not clear whether mobilization of 2-AG specifically from midbrain dopamine neurons is necessary for dopaminergic responses to external stimuli predicting forthcoming reward. Here, we use a viral-genetic strategy to prevent the expression of the 2-AG-synthesizing enzyme diacylglycerol lipase α (DGLα) from ventral tegmental area (VTA) dopamine cells in adult mice. We find that DGLα deletion from VTA dopamine neurons prevents depolarization-induced suppression of excitation (DSE), a form of 2-AG-mediated synaptic plasticity, in dopamine neurons. DGLα deletion also decreases effortful, cue-driven reward-seeking but has no effect on non-cued or low-effort operant tasks and other behaviors. Moreover, dopamine recording in the NAc reveals that deletion of DGLα impairs the transfer of accumbal dopamine signaling from a reward to its earliest predictors. These results demonstrate that 2-AG mobilization from VTA dopamine neurons is a necessary step for the generation of dopamine-based predictive associations that are required to direct and energize reward-oriented behavior.
Dopamine receptor activation regulates reward expectancy signals during cognitive control in primate prefrontal neurons
Authors: Ott Torben , Stein Anna Marlina , Nieder Andreas
Published: November 2023

Dopamine neurons respond to reward-predicting cues but also modulate information processing in the prefrontal cortex essential for cognitive control. Whether dopamine controls reward expectation signals in prefrontal cortex that motivate cognitive control is unknown. We trained two male macaques on a working memory task while varying the reward size earned for successful task completion. We recorded neurons in lateral prefrontal cortex while simultaneously stimulating dopamine D1 receptor (D1R) or D2 receptor (D2R) families using micro-iontophoresis. We show that many neurons predict reward size throughout the trial. D1R stimulation showed mixed effects following reward cues but decreased reward expectancy coding during the memory delay. By contrast, D2R stimulation increased reward expectancy coding in multiple task periods, including cueing and memory periods. Stimulation of either dopamine receptors increased the neurons’ selective responses to reward size upon reward delivery. The differential modulation of reward expectancy by dopamine receptors suggests that dopamine regulates reward expectancy necessary for successful cognitive control.
Bidirectional light-emitting diode as a visible light source driven by alternating current
Authors: Żak Mikołaj , Muziol Grzegorz , Siekacz Marcin , Bercha Artem , Hajdel Mateusz , Nowakowski-Szkudlarek Krzesimir , Lachowski Artur , Chlipała Mikołaj , Wolny Paweł , Turski Henryk , Skierbiszewski Czesław
Published: November 2023

Gallium nitride-based light-emitting diodes have revolutionized the lighting market by becoming the most energy-efficient light sources. However, the power grid, in example electricity delivery system, is built based on alternating current, which raises problems for directly driving light emitting diodes that require direct current to operate effectively. In this paper, we demonstrate a proof-of-concept device that addresses this fundamental issue – a gallium nitride-based bidirectional light-emitting diode. Its structure is symmetrical with respect to the active region, which, depending on the positive or negative bias, allows for the injection of either electrons or holes from each side. It is composed of two tunnel junctions that surround the active region. In this work, the optical and electrical properties of bidirectional light emitting diodes are investigated under direct and alternating current conditions. We find that the light is emitted in both directions of the supplied current, contrary to conventional light emitting diodes; hence, bidirectional light-emitting diodes can be considered a semiconductor light source powered directly with alternating current. In addition, we show that bidirectional light-emitting diodes can be stacked vertically to multiply the optical power achieved from a single device.
Direct comparison of spatial transcriptional heterogeneity across diverse Bacillus subtilis biofilm communities
Authors: Dergham Yasmine , Le Coq Dominique , Nicolas Pierre , Bidnenko Elena , Dérozier Sandra , Deforet Maxime , Huillet Eugénie , Sanchez-Vizuete Pilar , Deschamps Julien , Hamze Kassem , Briandet Romain
Published: November 2023

Bacillus subtilis can form various types of spatially organised communities on surfaces, such as colonies, pellicles and submerged biofilms. These communities share similarities and differences, and phenotypic heterogeneity has been reported for each type of community. Here, we studied spatial transcriptional heterogeneity across the three types of surface-associated communities. Using RNA-seq analysis of different regions or populations for each community type, we identified genes that are specifically expressed within each selected population. We constructed fluorescent transcriptional fusions for 17 of these genes, and observed their expression in submerged biofilms using time-lapse confocal laser scanning microscopy (CLSM). We found mosaic expression patterns for some genes; in particular, we observed spatially segregated cells displaying opposite regulation of carbon metabolism genes (gapA and gapB), indicative of distinct glycolytic or gluconeogenic regimes coexisting in the same biofilm region. Overall, our study provides a direct comparison of spatial transcriptional heterogeneity, at different scales, for the three main models of B. subtilis surface-associated communities.
Climate warming and elevated CO2 alter peatland soil carbon sources and stability
Authors: Ofiti Nicholas O. E. , Schmidt Michael W. I. , Abiven Samuel , Hanson Paul J. , Iversen Colleen M. , Wilson Rachel M. , Kostka Joel E. , Wiesenberg Guido L. B. , Malhotra Avni
Published: November 2023

Peatlands are an important carbon (C) reservoir storing one-third of global soil organic carbon (SOC), but little is known about the fate of these C stocks under climate change. Here, we examine the impact of warming and elevated atmospheric CO2 concentration (eCO2) on the molecular composition of SOC to infer SOC sources (microbe-, plant- and fire-derived) and stability in a boreal peatland. We show that while warming alone decreased plant- and microbe-derived SOC due to enhanced decomposition, warming combined with eCO2 increased plant-derived SOC compounds. We further observed increasing root-derived inputs (suberin) and declining leaf/needle-derived inputs (cutin) into SOC under warming and eCO2. The decline in SOC compounds with warming and gains from new root-derived C under eCO2, suggest that warming and eCO2 may shift peatland C budget towards pools with faster turnover. Together, our results indicate that climate change may increase inputs and enhance decomposition of SOC potentially destabilising C storage in peatlands.
Populational pan-ethnic screening panel enabled by deep whole genome sequencing
Authors: Yang Linfeng , Lin Zhe , Gao Yong , Zhang Jianguo , Peng Huanhuan , Li Yaqing , Che Jingang , Zhao Lijian , Zhang Jilin
Published: November 2023

Birth defect is a global threat to the public health systems. Mitigating neonatal anomalies is hampered by elusive molecular mechanisms of pathogenic mutations and poor subsequent translation into preventative measures. Applying appropriate strategies in China to promote reproductive health is particularly challenging, as the Chinese population compromises complex genomic diversity due to the inclusion of many ethnic groups with distinct genetic backgrounds. To investigate and evaluate the feasibility of implementing a pan-ethnic screening strategy, and guide future reproductive counselling, high-quality variants associated with autosome recessive (AR) diseases derived from the largest publicly available cohort of the Chinese population were re-analysed using a bottom-up approach. The analyses of gene carrier rates (GCRs) across distinct ethnic groups revealed that substantial heterogeneity existed potentially due to diverse evolutionary selection. The sampling population, sequencing coverage and underlying population structure contributed to the differential variants observed between ChinaMAP and the East Asian group in gnomAD. Beyond characteristics of GCR, potential druggable targets were additionally explored according to genomic features and functional roles of investigated genes, demonstrating that phase separation could be a therapeutic target for autosomal recessive diseases. A further examination of estimated GCR across ethnic groups indicated that most genes shared by at least two populations could be utilised to direct the design of a pan-ethnic screening application once sequencing and interpreting costs become negligible. To this end, a list of autosomal recessive disease genes is proposed based on the prioritised rank of GCR to formulate a tiered screening strategy.
Monovalent vaccination with inactivated SARS-CoV-2 BA.5 protects hamsters against Omicron but not non-Omicron variants
Authors: Ong Chon Phin , Tang Kaiming , Cheung Pak-Hin Hinson , Zhang Hongzhuo , Tang Tze-Tung , Xue Yaqian , Wang Junjue , To Kelvin Kai-Wang , Yuan Shuofeng , Ye Zi-Wei , Jin Dong-Yan
Published: November 2023

We compared the protective effects of inactivated SARS-CoV-2 vaccines derived from the ancestral and the currently circulating BA.5.2 strains against infection with multiple variants in Syrian golden hamsters. Vaccination with BA.5.2 effectively protected against infection with the Omicron subvariants including XBB.1, but not the Alpha or Delta variant. In contrast, hamsters vaccinated with the ancestral strain demonstrated decent neutralization activity against both the Omicron and non-Omicron variants. Our findings might instruct future design and formulation of SARS-CoV-2 vaccines.
Cumulative environmental quality is associated with breast cancer incidence differentially by summary stage and urbanicity
Authors: Gearhart-Serna Larisa M. , Mills Brittany A. , Hsu Hillary , Fayanju Oluwadamilola M. , Hoffman Kate , Devi Gayathri R.
Published: November 2023

Individual environmental contaminants have been associated with breast cancer; however, evaluations of multiple exposures simultaneously are limited. Herein, we evaluated associations between breast cancer summary stages and the Environmental Quality Index (EQI), which includes a range of environmental factors across five domains. The EQI (2000–2005) was linked to county-level age-standardized incidence rates (SIRs) obtained from the North Carolina Central Cancer Registry (2010–2014). Incidence rates and SIRs of total, in situ, localized, regional, and distant breast cancers were evaluated stratified by rural–urban status. In counties with poor environmental quality compared to those with good environmental quality, total breast cancer incidence was higher by 10.82 cases per 100,000 persons (95% CI 2.04, 19.60, p = 0.02). This association was most pronounced for localized breast cancer (β = 5.59, 95% CI 0.59, 10.58, p = 0.03). Higher incidence of early-stage disease (carcinoma in situ β = 5.25, 95% CI 2.34, 8.16, p = 0.00 and localized breast cancer β = 6.98, 95% CI 2.24, 11.73, p = 0.00) and total breast cancer (β = 11.44, 95% CI 3.01, 19.87, p = 0.01) occurred in counties with poor land quality, especially urban counties. Our analyses indicate significant associations between environmental quality and breast cancer incidence, which differ by breast cancer stage and urbanicity, identifying a critical need to assess cumulative environmental exposures in the context of cancer stage.
Self-supervised pre-training with contrastive and masked autoencoder methods for dealing with small datasets in deep learning for medical imaging
Authors: Wolf Daniel , Payer Tristan , Lisson Catharina Silvia , Lisson Christoph Gerhard , Beer Meinrad , Götz Michael , Ropinski Timo
Published: November 2023

Deep learning in medical imaging has the potential to minimize the risk of diagnostic errors, reduce radiologist workload, and accelerate diagnosis. Training such deep learning models requires large and accurate datasets, with annotations for all training samples. However, in the medical imaging domain, annotated datasets for specific tasks are often small due to the high complexity of annotations, limited access, or the rarity of diseases. To address this challenge, deep learning models can be pre-trained on large image datasets without annotations using methods from the field of self-supervised learning. After pre-training, small annotated datasets are sufficient to fine-tune the models for a specific task. The most popular self-supervised pre-training approaches in medical imaging are based on contrastive learning. However, recent studies in natural image processing indicate a strong potential for masked autoencoder approaches. Our work compares state-of-the-art contrastive learning methods with the recently introduced masked autoencoder approach “SparK” for convolutional neural networks (CNNs) on medical images. Therefore, we pre-train on a large unannotated CT image dataset and fine-tune on several CT classification tasks. Due to the challenge of obtaining sufficient annotated training data in medical imaging, it is of particular interest to evaluate how the self-supervised pre-training methods perform when fine-tuning on small datasets. By experimenting with gradually reducing the training dataset size for fine-tuning, we find that the reduction has different effects depending on the type of pre-training chosen. The SparK pre-training method is more robust to the training dataset size than the contrastive methods. Based on our results, we propose the SparK pre-training for medical imaging tasks with only small annotated datasets.