bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigations of Differential Hypoxemia During Venoarterial Membrane Oxygenation with and Without Impella Support
Authors: Neidlin Michael , Amiri Ali , Hugenroth Kristin , Steinseifer Ulrich
Published: June 2024

Purpose

Venoarterial extracorporeal membrane oxygenation (VA ECMO) is used in patients with refractory cardiac or cardio-pulmonary failure. Native ventricular output interacts with VA ECMO flow and may hinder sufficient oxygenation to the heart and the brain. Further on, VA ECMO leads to afterload increase requiring ventricular unloading. The aim of the study was to investigate aortic blood flow and oxygenation for various ECMO settings and cannula positions with a numerical model.

Methods

Four different aortic cannula tip positions (ascending aorta, descending aorta, abdominal aorta, and iliac artery) were included in a model of a human aorta. Three degrees of cardiac dysfunction and VA ECMO support (50%, 75% and 90%) with a total blood flow of 6 l/min were investigated. Additionally, the Impella CP device was implemented under 50% support condition. Blood oxygen saturation at the aortic branches and the pressure acting on the aortic valve were calculated.

Results

A more proximal tip orientation is necessary to increase oxygen supply to the supra-aortic and coronary arteries for 50% and 75% support. During the 90% support scenario, proper oxygenation can be achieved independently of tip position. The use of Impella reduces afterload by 8–17 mmHg and vessel oxygenation is similar to 50% VA ECMO support. Pressure load on the aortic valve increases with more proximal tip position and is decreased during Impella use.

Conclusions

We present a simulation model for the investigation of hemodynamics and blood oxygenation with various mechanical circulatory support systems. Our results underline the intricate and patient-specific relationship between extracorporeal support, cannula tip orientation and oxygenation capacity.
A Novel Cooling System by Surface Corrugation and Nanofluid Utilization for the Performance Improvement of Photovoltaic Module Coupled with Thermoelectric Generator and Efficient Computations by Using Artificial Neural Network-Based Hybrid Scheme
Authors: Selimefendigil Fatih , Okulu Damla , Oztop Hakan F.
Published: June 2024

For a photovoltaic module coupled with thermoelectric generator, a unique wavy cooling channel is proposed, and its performance is numerically assessed by using three-dimensional computations. The cooling channel uses nanofluid of alumina–water with various shaped nanoparticles (spherical, cylindrical and brick). Numerical simulations are performed for a range of parameters for the corrugation amplitude ($$0 \le \text {Amp} \le 0.1$$

0
≤
Amp
≤
0.1

), wave frequency ($$2 \le \text {Nf} \le 16$$

2
≤
Nf
≤
16

), nanoparticle loading quantity ($$0 \le \text {SVF} \le 0.03$$

0
≤
SVF
≤
0.03

), and nanoparticle shape (spherical, brick, and cylindrical). We analyze the photovoltaic module’s average temperature and temperature uniformity for a variety of parameter variations. When nanofluid and greater channel corrugation amplitudes are utilized, the average panel surface temperature is decreased more. A wavy shape of the cooling channel at the maximum corrugation amplitude yields a cell temperature reduction of 1.88 $$^\text {o}$$

o

C, while frequency has little impact on average cell temperature and its uniformity. The best-performing particles are those with cylindrical shapes, and the drop-in average photovoltaic temperature with solid volume fraction is essentially linear. As utilizing cylindrical-shaped particles, the average temperature of corrugated cooling channels decreases by around 1.9 $$^\text {o}$$

o

C as compared to flat cooling channels with base fluid at the greatest solid volume fraction. As compared to un-cooled photovoltaic, cell temperature drops by around 43.2 $$^\text {o}$$

o

C when employing thermoelectric generator. However, temperature drop value of 59.8 $$^\text {o}$$

o

C can be obtained by using thermoelectric generator and nano-enhanced wavy cooling channel utilizing cylindrical-shaped nanoparticles. An hybrid computational strategy for the fully coupled system of photovoltaic with cooling system is provided, which reduces the computational time by a factor of 75.
System Identification Based on Experimental Technique Using Stability Boundary Locus Method for Linear Fractional Order Systems
Authors: Yüce Ali
Published: June 2024

Fractional calculus is an important mathematical tool that is widely used in control systems. It is established in the literature that fractional order models are more accurate and more effective in system modelling. In this study, an alternative and novel technique is proposed to identify the fractional order time-delayed model of an unknown system. The method is based on obtaining the approximate stability boundary locus (SBL) curve of the unknown system by applying three different experimental tests. Three points on the SBL curve are determined by the experimental tests and then the parameters of the fractional order time-delayed model are computed by solving the nonlinear systems of equation. The system model with double fractional order element plus a time delay is obtained using the proposed method. The proposed method is explained through simulations on a twin rotor system. The proposed method is also used in model order reduction calculation of the higher order transfer functions.
Trawling through time: reconstructing a late nineteenth century beam trawl for scientific inshore fishery investigations
Authors: Hunt Georgina L. , Engelhard Georg H. , Pinnegar John K. , Wigham Benjamin D. , Polunin Nicholas V. C.
Published: June 2024

Understanding long-term change in fish populations often relies on comparing catches from historical and contemporary trawl surveys. However, such comparisons may not resolve biases associated with differences in fishing gears and their relative catchabilities. It is possible to reduce these uncertainties by replicating historical trawl gear and practices. With the availability of unique historical catch data, we investigated the trawl gear employed by the Northumberland Sea Fisheries Committee (NSFC) during scientific surveys conducted between 1892–1913 in inshore waters of the Northumberland coast (UK), and describe our attempt to reconstruct the gear using currently available materials. We reviewed the historical literature, photographs and acquired technical expertise to reconstruct a late nineteenth century beam trawl used by the NSFC. The replica gear consisted of a 6.7 m beam connected by two Brixham style wrought-iron trawl heads, which held open a triangular-shaped trawl net with rounded ground-rope. Following construction, we tested the performance and catchability of the replica gear by conducting comparative trawls using a modern otter trawl in August 2018 and March 2019. Both trawl gears exhibited similar catches for flatfish in August trials, yet a higher proportion of individuals were landed by the otter trawl in March. Zero or negligible catches were exhibited by the replica gear during this period. This work collates relevant information to describe the evolution, design and functioning of late nineteenth century beam trawls used around the British Isles, providing an important repository for investigators interested in trawl technology and survey designs.
Glycemic control and cancer outcomes in oncologic patients with diabetes: an Italian Association of Medical Oncology (AIOM), Italian Association of Medical Diabetologists (AMD), Italian Society of Diabetology (SID), Italian Society of Endocrinology (SIE), Italian Society of Pharmacology (SIF) multidisciplinary critical view
Authors: Natalicchio A. , Marrano N. , Montagnani M. , Gallo M. , Faggiano A. , Zatelli MC , Argentiero A. , Del Re M. , D’Oronzo S. , Fogli S. , Franchina T. , Giuffrida D. , Gori S. , Ragni A. , Marino G. , Mazzilli R. , Monami M. , Morviducci L. , Renzelli V. , Russo A. , Sciacca L. , Tuveri E. , Cortellini A. , Di Maio M. , Candido R. , Perrone F. , Aimaretti G. , Avogaro A. , Silvestris N. , Giorgino F.
Published: June 2024

Background: Increasing evidence suggests that diabetes increases the risk of developing different types of cancer. Hyperinsulinemia, hyperglycemia and chronic inflammation, characteristic of diabetes, could represent possible mechanisms involved in cancer development in diabetic patients. At the same time, cancer increases the risk of developing new-onset diabetes, mainly caused by the use of specific anticancer therapies. Of note, diabetes has been associated with a ∼10% increase in mortality for all cancers in comparison with subjects who did not have diabetes. Diabetes is associated with a worse prognosis in patients with cancer, and more recent findings suggest a key role for poor glycemic control in this regard. Nevertheless, the association between glycemic control and cancer outcomes in oncologic patients with diabetes remains unsettled and poorly debated. Purpose: The current review seeks to summarize the available evidence on the effect of glycemic control on cancer outcomes, as well as on the possibility that timely treatment of hyperglycemia and improved glycemic control in patients with cancer and diabetes may favorably affect cancer outcomes.
Enhancing watershed management in developing countries: insights from Ethiopia
Authors: Naji Temesgen Argaw , Teka Meskerem Abi , Alemu Esubalew Abate
Published: June 2024

Natural resource degradation poses a major challenge to the sustainable livelihoods of farmers in developing countries, hindering progress toward achieving sustainable rural development. Watershed development and management practices (WDMPs) are powerful tools for enhancing sustainable rural development in developing countries. These practices have been shown to significantly improve livelihoods and food security. This research examined how WDM programs help achieve sustainable development in rural areas, focusing on examples from Ethiopia. This study used a systematic literature review (SLR) approach following a PRISMA review protocol. The research question was formulated using the CIMO (context, intervention, mechanisms, and outcomes) approach: “Does the watershed development and management (WDM) initiative lead to sustainable rural livelihoods?” Considering this research question, the findings indicated that WDM contributes to the socioeconomic and environmental sustainability of rural communities. It does this by enhancing households’ livelihood in terms of income generation, employment opportunities, agricultural productivity, and improvements in social services and infrastructure, as evidenced by numerous studies, thereby leading to better livelihoods and food security. This research also emphasizes the importance of community participation and supportive policies and legal frameworks for successful WDM. Overall, the systematic literature review highlights the potential of WDMPs in promoting sustainable rural development in developing countries such as Ethiopia while also highlighting the need for a supportive policy and institutional environment.
Multivariate Bayesian Time-Series Model with Multi-temporal Convolution Network for Forecasting Stock Market During COVID-19 Pandemic
Authors: Ray Paramita , Ganguli Bhaswati , Chakrabarti Amlan
Published: June 2024

The paper proposes a hybrid algorithm for forecasting multiple correlated time-series data, which consists of two main steps. First, it employs a multivariate Bayesian structural time series (MBSTS) approach as a base step. This method allows for the incorporation of potentially high-dimensional regression components, and it utilizes spike and slab priors to identify a parsimonious model. Second, the algorithm includes a post-model fitting diagnostic step where the residuals from the MBSTS step are processed through a multi-input/output temporal convolutional network (M-TCN) with multiple time scale feature learning. This step serves as an alternative to traditional subjective residual-based diagnostic procedures in time-series analysis, with the aim of improving forecasting accuracy. The key advantage of the M-TCN is its ability to capture sequential information efficiently. The M-TCN expands the field of convolution kernel without increasing the number of parameters, thus enhancing the capacity of model to capture complex sequential patterns. The paper presents two applications showcasing the effectiveness of the proposed hybrid algorithm. First, it utilizes pre-lockdown data from eleven Nifty stock sectoral indices to predict stock price movements, including the initial post-lockdown upturn. In the second application, it focuses on stock market data from pharmaceutical companies involved in manufacturing COVID-19 vaccines. In both cases, sentiment data sourced from newspapers and social media serve as the regression component. Through rigorous analysis, the paper demonstrates that the hybrid model outperforms various benchmark models, including LSTM, Bidirectional Encoder Representations from Transformers (BERT)-based LSTM, Deep Transformer Model, and GRU, among others, in terms of forecasting accuracy. This underscores the utility of the hybrid algorithm, particularly in predicting stock market trends during the COVID-19 pandemic period and its associated market dynamics.
Two assessors for the ordinary examination ought to result in stricter requirements for justifying appeals
Authors: Abrahamsen Eirik Bjorheim , Moen Vegard , Selvik Jon Tømmerås
Published: June 2024

All students at Norwegian universities and colleges have the right to complain about ordinary grading decisions. When an appeal is made, two new examiners are appointed, at least one of whom should be external. The handling of appeals in the current system is to be blind, meaning that the examiners handling the complaint should not be aware of the original grade. It also means that they are not to receive information regarding the examiners’ reasoning for the original grade or the student’s reasoning for the complaint. In this article, we discuss whether the current appeal grading system with blind grading is appropriate when ordinary appeal grading is conducted by two examiners. We argue that the students' legal rights are not in conflict with the principle that good decision-making processes should be well-informed before decisions are made. We conclude that, in cases where two assessors are used for the ordinary examination, we ought to abolish the blind aspect in the current appeal grading system.
Recycling potential of medical plastic waste
Authors: Apevienyeku Holali Kwami , Ampofo Joshua , Amankwaa Amoako James
Published: June 2024

Medical plastic waste threatens the environment and human health if not properly handled and disposed of. This study used field visits, multi-criteria decision analysis, material testing, and data analysis to assess the feasibility of recycling medical plastic waste. The study identified medical plastic products (syringes, intravenous bags, and infusion sets) with high recyclability potential and proposed targeted recommendations for improving waste management practices. Medical plastic waste generation rates in kg/bed/day were 0.486 and 0.428. 55 kg/day and 5 kg/day of recyclable medical plastic waste are generated at KATH and KNUST hospitals, respectively. The contextual relevance of this research extends beyond the Ghanaian healthcare system, with implications for waste management practices in low and middle-income countries by contributing to the advancement of sustainable waste management practices.
Effect of elevated temperature on the mechanical properties of geopolymer concrete: a critical review
Authors: Rihan Mohammed Ali M. , Onchiri Richard Ocharo , Gathimba Naftary , Sabuni Bernadette
Published: June 2024

The need for concrete is increasing exponentially due to the growing population and fast urbanization. The primary constituent in concrete is ordinary Portland cement (OPC). Producing cement involves a significant quantity of embodied energy and leads to the release of greenhouse gases. Geopolymer concrete (GPC) was created to address the adverse environmental effects of carbon dioxide emissions (CO2) and the overdependence on fossil fuels in cement production. In addition to reducing environmental consequences, geopolymer concrete shows outstanding resistance to higher temperatures compared to OPC concrete, which maintains temperatures up to 1200 °C. This review investigates the field of GPC, focusing on its ability to withstand high temperatures. It briefly reviews geopolymer concrete's mechanical properties at high temperatures. It has been observed that residual compressive strength, which is essential in high-temperature GPC studies, generally increases to 150–350 °C but decreases beyond 400 °C because of microcrack formation. Moreover, enhanced tensile strength is demonstrated up to 300 °C, with a noticeable decrease above 800 °C. This study emphasizes the potential of geopolymer concrete for improving fire protection measures in the building industry.
The key to understanding core knowledge resides in the fetus
Authors: Reid Vincent M.
Published: June 2024

What Babies Know outlines a compelling case for why infancy research is fundamental for conceptualizing what it is to be human. There is another period in human development that is relatively inaccessible, yet is more important. In order to truly understand the nature of core knowledge, perception, and cognition, we must start not with the infant, but with the fetus.
More than language is needed to represent and combine different core knowledge components
Authors: Krøjgaard Peter , Sonne Trine , Kingo Osman S.
Published: June 2024

We question Spelke's key claim that the medium, in which contents from different core knowledge systems can be represented and combined, is language-based. Recalling an episodic memory, playing chess, and conducting mental rotation are tasks where core knowledge information is represented and combined. Although these tasks can be described by means of language, these tasks are not inherently language-based. Hence, language may be an important subset of an abstraction medium – not the medium as such.
Down the drain: reconstructing social practice from the content of two sewers in a Late Antique bathhouse in Jerash, Jordan
Authors: Blanke Louise , Bangsgaard Pernille , McPhillips Stephen , Pappalardo Raffaella , Penn Tim
Published: June 2024

This contribution examines social practices in the Central Bathhouse in Jerash in Late Antiquity based on the ceramic assemblage, vessel glass, faunal remains, and small finds retrieved from two sections of the bathhouse's sewer. We argue that although the bathhouse underwent significant architectural alterations from its construction in the 4th c. CE to its abandonment in the late 7th, the activities taking place inside the building remained largely the same. Our study shows that even towards the end of the bathhouse's lifespan, bodily grooming remained integral to the bathing experience, while food and drink were consumed on the premises even though the bathing facilities had been reduced to a bare minimum. The faunal remains indicate the type of food consumed, while the small finds illustrate a lively environment where gaming and gambling took place in a social space frequented by men, women, and children.
Poroelastic Response to Karst Conduit Pressurization: A Finite Element Modeling Exercise Toward the Use of Tiltmeters in Karst Aquifer Monitoring Applications
Authors: Gochenour Jacob Alexander , Rinehart Alex J. , Luhmann Andrew J. , Grapenthin Ronni , Bilek Susan L.
Published: June 2024

Tiltmeters have the potential to resolve ground deformation due to changes in hydraulic head induced by conduit pressurization. Conduit pressure variations cause groundwater to be stored or released from storage within the surrounding rock matrix. We modeled this process and infer whether the resulting deformation is measurable with tiltmeters and what behavior to expect by fully coupling porous media flow and solid mechanics in a poroelastic, 2D finite element model. Parameter sets globally representative of Paleozoic, Mesozoic, and Cenozoic confined and unconfined aquifers are considered. Our analysis focuses on the impact of the parameterization on pore pressure, vertical displacement, and tilt. We find that the spatial distribution of the poroelastic signal depends on the hydraulic diffusivity, and its magnitude depends on the mechanical and coupling parameters. Additional analysis of the impacts of conduit radius and depth suggests that tilt polarity could be an indicator of conduit location and relative conduit size. We calibrated the model to data observations acquired at the Santa Fe River Sink‐Rise system in north‐central Florida, US. We find that an overlying clay‐rich layer may act to partially confine the aquifer. Although the observed tilt signal is present in radial and transverse components and polarity reversals occur, we were able to recover the magnitude and general trend of the tilt response.
A Comparative Study on Wind Profiles and Surface Aerodynamic Parameters of Typhoons Over Coastland and Coastal Sea
Authors: Tang Shengming , Wang Kai , Yu Hui , Li Tiantian , Tang Jie
Published: June 2024

Understanding the aerodynamic characteristics of landfalling typhoons is of great importance for both wind engineering and meteorology. This study comparatively investigated the near‐surface wind profiles and aerodynamic parameters over coastland and coastal sea areas using typhoon observational data collected by Doppler wind lidars and wind tower anemometers during the passage of 15 typhoons that made landfall over China during 2009–2020. Specifically, the three surface aerodynamic parameters of roughness length, friction velocity, and drag coefficient (Cd) were obtained using the logarithmic law wind profile method. Results showed that the near‐surface wind profiles became much closer to the power law wind profile with increase in wind speed. The values of roughness length and friction velocity over the coastal sea were found to exceed those over coastland areas when the 10‐m wind speed (U(10)) was larger than 18 m s−1. The critical wind speed at which Cd peaks over the coastal sea was found to be 24 m s−1. There are two peaks in the variation of Cd with U(10) under the condition of onshore wind over the sea, which has never been reported in previous observational studies. Finally, a formula for Cd was proposed to describe the variation in Cd with U(10) under the condition of onshore wind over land, which is expected to be applied in the typhoon surface layer scheme to improve numerical simulation of landfalling typhoons.
Explaining the Mechanism of Multiscale Groundwater Drought Events: A New Perspective From Interpretable Deep Learning Model
Authors: Cai Hejiang , Shi Haiyun , Zhou Zhaoqiang , Liu Suning , Babovic Vladan
Published: June 2024

This study presents a new approach to understand the causes of groundwater drought events with interpretable deep learning (DL) models. As prerequisites, accurate long short‐term memory (LSTM) models for simulating groundwater are built for 16 regions representing three types of spatial scales in the southeastern United States, and standardized groundwater index is applied to identify 233 groundwater drought events. Two interpretation methods, expected gradients (EG) and additive decomposition (AD), are adopted to decipher the DL‐captured patterns and inner workings of LSTM networks. The EG results show that: (a) temperature‐related features were the primary drivers of large‐scale groundwater droughts, with their importance increasing from 56.1% to 63.1% as the drought events approached from 6 months to 15 days. Conversely, precipitation‐related features were found to be the dominant factors in the formation of groundwater drought in small‐scale catchments, with the overall importance ranging from 59.8% to 53.3%; (b) Seasonal variations in the importance of temperature‐related factors are inversely related between large and small spatial scales, being more significant in summer for larger regions and in winter for catchments; and (c) temperature‐related factors exhibited an overall “trigger effect” on causing groundwater drought events in the studying areas. The AD method unveiled how the LSTM network behaved differently in retaining and discarding information when emulating different groundwater droughts. In summary, this study provides a new perspective for the causes of groundwater drought events and highlights the potential and prospect of interpretable DL in enhancing our understanding of hydrological processes.
Integrated Geophysical‐Petrological 3D‐Modeling of the West and Central African Rift System and Its Adjoining Areas
Authors: Fosso Téguia M Estelle Eric , Ebbing Jörg , Haas Peter , Szwillus Wolfgang
Published: June 2024

This study addresses the lithospheric structure of the West and Central African rift system (WCARS) and explores its origin and development in relation to the enigmatic Cameroon volcanic line (CVL). Based on a recent seismic tomography model, we subdivide the areas in tectonic domains. We perform integrated 3D geophysical and petrological forward modeling. By exploring the thickness and composition of different domains, we compare the model response to the observed topography and gravity anomalies, under consideration of the available seismic Moho depth points. Our model reveals three distinct domains within the study area: The WCARS is predominantly underlain by a Phanerozoic‐type lithospheric mantle, surrounded by the West African and the Congo Cratons, where the lithospheric mantle has a Proterozoic‐type signature. Between these domains, we identify a transition area where lithospheric thickness changes rapidly. Our preferred model shows significant variability of crustal thickness from 20 km in the rift area to 50 km beneath the cratons accompanied by thin lithosphere of 80 km in the rift area to thick lithosphere of up to 240 km beneath the cratons. The final model confirms that the WCARS' origin is passive, and suggests that the origin of the CVL, particularly its continental part, is the result of two tectonic events: (a) V‐shaped opening of the lithospheric mantle beneath the WCARS, resulting in (b) a strong variation of the lithosphere thickness at the transition between the rift zone and the northwestern part of the Congo craton.
Predicting Shoreline Changes Along the California Coast Using Deep Learning Applied to Satellite Observations
Authors: Adusumilli Susheel , Cirrito Nicholas , Engeman Laura , Fiedler Julia W. , Guza R. T. , Lange Athina M. Z. , Merrifield Mark A. , O'Reilly William , Young Adam P.
Published: June 2024

Understanding and predicting changes in shoreline location are critical for coastal planners. In situ monitoring is accurate but not widely available. Satellite observations of shorelines have global coverage, but their accuracy and predictive capacity have not been fully explored. Abundant beach surveys and extensive wave observations in Southern California provide a unique ground truth for the interpretation of satellite‐derived recently wetted waterlines. We combine 23 years of waterline position estimates from satellite imagery with nearshore wave hindcasts and tides to train and test a deep neural network (DNN). The trained DNN uses only tides and waves as predictors at transects with satellite coverage and wave estimates to predict beach width and, for the first time, seasonal average beach slopes. Beach width changes hindcast using DNN have at least fair skill (>0.3) for 50% of transects, where the skill was calculated relative to the mean of extensive new in situ survey data from in San Diego County. The DNN also predicted shoreline changes to within 10 m (the nominal uncertainty in satellite‐derived shorelines) for 64% of transects lacking ground truth. DNN and survey estimates of seasonal beach slope changes also agree qualitatively.
DDX41 haploinsufficiency causes inefficient hematopoiesis under stress and cooperates with p53 mutations to cause hematologic malignancy
Authors: Stepanchick Emily , Wilson Andrew , Sulentic Analise M. , Choi Kwangmin , Hueneman Kathleen , Starczynowski Daniel T. , Chlon Timothy M.
Published: June 2024

Germline heterozygous mutations in DDX41 predispose individuals to hematologic malignancies in adulthood. Most of these DDX41 mutations result in a truncated protein, leading to loss of protein function. To investigate the impact of these mutations on hematopoiesis, we generated mice with hematopoietic-specific knockout of one Ddx41 allele. Under normal steady-state conditions, there was minimal effect on lifelong hematopoiesis, resulting in a mild yet persistent reduction in red blood cell counts. However, stress induced by transplantation of the Ddx41+/− BM resulted in hematopoietic stem/progenitor cell (HSPC) defects and onset of hematopoietic failure upon aging. Transcriptomic analysis of HSPC subsets from the transplanted BM revealed activation of cellular stress responses, including upregulation of p53 target genes in erythroid progenitors. To understand how the loss of p53 affects the phenotype of Ddx41+/− HSPCs, we generated mice with combined Ddx41 and Trp53 heterozygous deletions. The reduction in p53 expression rescued the fitness defects in HSPC caused by Ddx41 heterozygosity. However, the combined Ddx41 and Trp53 mutant mice were prone to developing hematologic malignancies that resemble human myelodysplastic syndrome and acute myeloid leukemia. In conclusion, DDX41 heterozygosity causes dysregulation of the response to hematopoietic stress, which increases the risk of transformation with a p53 mutation.
Coronin 2B deficiency induces nucleolar stress and neuronal apoptosis
Authors: Wu Hongjiao , Yang Yujie , Yi Wanying , Qiu Yue , Ma Shuangshuang , Xu Jinying , Fan Yingying , Chen Yuewen , Chen Yu
Published: June 2024

In eukaryotes, the nucleolus is the critical non-membranous organelle within nuclei that is responsible for ribosomal DNA (rDNA) transcription and ribosome biogenesis. The transcription of rDNA, a rate-limiting step for ribosome biogenesis, is tightly regulated to meet the demand for global protein synthesis in response to cell physiology, especially in neurons, which undergo rapid changes in morphology and protein composition during development and synaptic plasticity. However, it is unknown how the pre-initiation complex for rDNA transcription is efficiently assembled within the nucleolus in neurons. Here, we report that the nucleolar protein, coronin 2B, regulates rDNA transcription and maintains nucleolar function through direct interaction with upstream binding factor (UBF), an activator of RNA polymerase I transcriptional machinery. We show that coronin 2B knockdown impairs the formation of the transcription initiation complex, inhibits rDNA transcription, destroys nucleolar integrity, and ultimately induces nucleolar stress. In turn, coronin 2B-mediated nucleolar stress leads to p53 stabilization and activation, eventually resulting in neuronal apoptosis. Thus, we identified that coronin 2B coordinates with UBF to regulate rDNA transcription and maintain proper nucleolar function in neurons.
Emergent quantum phase transition of a Josephson junction coupled to a high-impedance multimode resonator
Authors: Giacomelli Luca , Ciuti Cristiano
Published: June 2024

The physics of a single Josephson junction coupled to a resistive environment is a long-standing fundamental problem at the center of an intense debate, strongly revived by the advent of superconducting platforms with high-impedance multimode resonators. Here we investigate the emergent criticality of a junction coupled to a multimode resonator when the number of modes is increased. We demonstrate how the multimode environment renormalizes the Josephson and capacitive energies of the junction so that in the thermodynamic limit the charging energy dominates when the impedance is larger than the resistance quantum and is negligible otherwise, independently from the bare ratio between the two energy scales and the compact or extended nature of the phase of the junction. Via exact diagonalization, we find that the transition surprisingly stems from a level anticrossing involving not the ground state, but the first excited state, whose energy gap vanishes in the thermodynamic limit. We clarify the nature of the two phases by pointing at a different behavior of the ground and excited states and we show that at the transition point the spectrum displays universality not only at low frequencies. In agreement with recent experiments, we reveal striking spectral signatures of the phase transition.
Obesity-associated microbiomes instigate visceral adipose tissue inflammation by recruitment of distinct neutrophils
Authors: Shantaram Dharti , Hoyd Rebecca , Blaszczak Alecia M. , Antwi Linda , Jalilvand Anahita , Wright Valerie P. , Liu Joey , Smith Alan J. , Bradley David , Lafuse William , Liu YunZhou , Williams Nyelia F. , Snyder Owen , Wheeler Caroline , Needleman Bradley , Brethauer Stacy , Noria Sabrena , Renton David , Perry Kyle A. , Nagareddy Prabha , Wozniak Daniel , Mahajan Sahil , Rana Pranav S. J. B. , Pietrzak Maciej , Schlesinger Larry S. , Spakowicz Daniel J. , Hsueh Willa A.
Published: June 2024

Neutrophils are increasingly implicated in chronic inflammation and metabolic disorders. Here, we show that visceral adipose tissue (VAT) from individuals with obesity contains more neutrophils than in those without obesity and is associated with a distinct bacterial community. Exploring the mechanism, we gavaged microbiome-depleted mice with stool from patients with and without obesity during high-fat or normal diet administration. Only mice receiving high-fat diet and stool from subjects with obesity show enrichment of VAT neutrophils, suggesting donor microbiome and recipient diet determine VAT neutrophilia. A rise in pro-inflammatory CD4+ Th1 cells and a drop in immunoregulatory T cells in VAT only follows if there is a transient spike in neutrophils. Human VAT neutrophils exhibit a distinct gene expression pattern that is found in different human tissues, including tumors. VAT neutrophils and bacteria may be a novel therapeutic target for treating inflammatory-driven complications of obesity, including insulin resistance and colon cancer.
Implicating the red body of Nannochloropsis in forming the recalcitrant cell wall polymer algaenan
Authors: Gee Christopher W. , Andersen-Ranberg Johan , Boynton Ethan , Rosen Rachel Z. , Jorgens Danielle , Grob Patricia , Holman Hoi-Ying N. , Niyogi Krishna K.
Published: June 2024

Stramenopile algae contribute significantly to global primary productivity, and one class, Eustigmatophyceae, is increasingly studied for applications in high-value lipid production. Yet much about their basic biology remains unknown, including the nature of an enigmatic, pigmented globule found in vegetative cells. Here, we present an in-depth examination of this “red body,” focusing on Nannochloropsis oceanica. During the cell cycle, the red body forms adjacent to the plastid, but unexpectedly it is secreted and released with the autosporangial wall following cell division. Shed red bodies contain antioxidant ketocarotenoids, and overexpression of a beta-carotene ketolase results in enlarged red bodies. Infrared spectroscopy indicates long-chain, aliphatic lipids in shed red bodies and cell walls, and UHPLC-HRMS detects a C32 alkyl diol, a potential precursor of algaenan, a recalcitrant cell wall polymer. We propose that the red body transports algaenan precursors from plastid to apoplast to be incorporated into daughter cell walls.
Hydropower capacity factors trending down in the United States
Authors: Turner Sean W. D. , Ghimire Ganesh R. , Hansen Carly , Singh Debjani , Kao Shih-Chieh
Published: June 2024

The United States hydropower fleet has faced increasing environmental and regulatory pressures over the last half century, potentially constraining total generation. Here we show that annual capacity factor has declined at four fifths of United States hydropower plants since 1980, with two thirds of decreasing trends significant at p < 0.05. Results are based on an analysis of annual energy generation totals and nameplate capacities for 610 plants (>5 megawatt), representing 87% of total conventional hydropower capacity in the United States. On aggregate, changes in capacity factor imply a fleetwide, cumulative generation decrease of 23% since 1980 before factoring in capacity upgrades—akin to retiring a Hoover Dam once every two to three years. Changes in water availability explain energy decline in only 21% of plants, highlighting the importance of non-climatic drivers of generation, including deterioration of plant equipment as well as changes to dam operations in support of nonpower objectives.
Structural basis for potent neutralization of human respirovirus type 3 by protective single-domain camelid antibodies
Authors: Johnson Nicole V. , van Scherpenzeel Revina C. , Bakkers Mark J. G. , Ramamohan Ajit R. , van Overveld Daan , Le Lam , Langedijk Johannes P. M. , Kolkman Joost A. , McLellan Jason S.
Published: June 2024

Respirovirus 3 is a leading cause of severe acute respiratory infections in vulnerable human populations. Entry into host cells is facilitated by the attachment glycoprotein and the fusion glycoprotein (F). Because of its crucial role, F represents an attractive therapeutic target. Here, we identify 13 F-directed heavy-chain-only antibody fragments that neutralize recombinant respirovirus 3. High-resolution cryo-EM structures of antibody fragments bound to the prefusion conformation of F reveal three distinct, previously uncharacterized epitopes. All three antibody fragments bind quaternary epitopes on F, suggesting mechanisms for neutralization that may include stabilization of the prefusion conformation. Studies in cotton rats demonstrate the prophylactic efficacy of these antibody fragments in reducing viral load in the lungs and nasal passages. These data highlight the potential of heavy-chain-only antibody fragments as effective interventions against respirovirus 3 infection and identify neutralizing epitopes that can be targeted for therapeutic development.
Coexpression enhances cross-species integration of single-cell RNA sequencing across diverse plant species
Authors: Passalacqua Michael John , Gillis Jesse
Published: June 2024

Single-cell RNA sequencing is increasingly used to investigate cross-species differences driven by gene expression and cell-type composition in plants. However, the frequent expansion of plant gene families due to whole-genome duplications makes identification of one-to-one orthologues difficult, complicating integration. Here we demonstrate that coexpression can be used to trim many-to-many orthology families down to identify one-to-one gene pairs with proxy expression profiles, improving the performance of traditional integration methods and reducing barriers to integration across a diverse array of plant species.
Ancient Egyptian scribes and specific skeletal occupational risk markers (Abusir, Old Kingdom)
Authors: Brukner Havelková Petra , Dulíková Veronika , Bejdová Šárka , Vacková Jana , Velemínský Petr , Bárta Miroslav
Published: June 2024

Men with writing proficiency enjoyed a privileged position in ancient Egyptian society in the third millennium BC. Research focusing on these officials of elevated social status (“scribes”) usually concentrates on their titles, scribal statues, iconography, etc., but the individuals themselves, and their skeletal remains, have been neglected. The aim of this study is to reveal whether repetitive tasks and maintained postures related to scribal activity can manifest in skeletal changes and identify possible occupational risk factors. A total of 1767 items including entheseal changes, non-metric traits, and degenerative changes were recorded from the human remains of 69 adult males of well-defined social status categories from the necropolis at Abusir (2700–2180 BC). Statistically significant differences between the scribes and the reference group attested a higher incidence of changes in scribes and manifested themselves especially in the occurrence of osteoarthritis of the joints. Our research reveals that remaining in a cross-legged sitting or kneeling position for extended periods, and the repetitive tasks related to writing and the adjusting of the rush pens during scribal activity, caused the extreme overloading of the jaw, neck and shoulder regions.
Unconventional acoustic wave propagation transitions induced by resonant scatterers in the high-density limit
Authors: Matis Bernard R. , Liskey Steven W. , Gangemi Nicholas T. , Edmunds Aaron D. , Wilson William B. , Houston Brian H. , Baldwin Jeffrey W. , Photiadis Douglas M.
Published: June 2024

Experiments on ultrasound propagation through a gel doped with resonant encapsulated microbubbles provided evidence for a discontinuous transition between wave propagation regimes at a critical excitation frequency. Such behavior is unlike that observed for soft materials doped with non-resonant air or through liquid foams, and disagrees with a simple mixture model for the effective sound speed. Here, we study the discontinuous transition by measuring the transition as a function of encapsulated microbubble volume fraction. The results show the transition always occurs in the strong-scattering limit (l/λ < 1, l and λ are the mean free path and wavelength, respectively), that at the critical frequency the effective phase velocity changes discontinuously to a constant value with increasing microbubble volume fraction, and the measured critical frequency shows a power law dependence on microbubble volume fraction. The results cannot be explained by multiple scattering theory, viscous effects, mode decoupling, or a critical density of states. It is hypothesized the transition depends upon the microbubble on-resonance effective properties, and we discuss the results within the context of percolation theory. The results shed light on the discontinuous transition’s physics, and suggest soft materials can be engineered in this manner to achieve a broad range of physical properties with potential application in ultrasonic actuators and switches.
Siderite and vivianite as energy sources for the extreme acidophilic bacterium Acidithiobacillus ferrooxidans in the context of mars habitability
Authors: Silva Gabriel Gonçalves , Vincenzi Roberta Almeida , de Araujo Gabriel Guarany , Venceslau Sara Jéssica Soja , Rodrigues Fabio
Published: June 2024

Past and present habitability of Mars have been intensely studied in the context of the search for signals of life. Despite the harsh conditions observed today on the planet, some ancient Mars environments could have harbored specific characteristics able to mitigate several challenges for the development of microbial life. In such environments, Fe2+ minerals like siderite (already identified on Mars), and vivianite (proposed, but not confirmed) could sustain a chemolithoautotrophic community. In this study, we investigate the ability of the acidophilic iron-oxidizing chemolithoautotrophic bacterium Acidithiobacillus ferrooxidans to use these minerals as its sole energy source. A. ferrooxidans was grown in media containing siderite or vivianite under different conditions and compared to abiotic controls. Our experiments demonstrated that this microorganism was able to grow, obtaining its energy from the oxidation of Fe2+ that came from the solubilization of these minerals under low pH. Additionally, in sealed flasks without CO2, A. ferrooxidans was able to fix carbon directly from the carbonate ion released from siderite for biomass production, indicating that it could be able to colonize subsurface environments with little or no contact with an atmosphere. These previously unexplored abilities broaden our knowledge on the variety of minerals able to sustain life. In the context of astrobiology, this expands the list of geomicrobiological processes that should be taken into account when considering the habitability of environments beyond Earth, and opens for investigation the possible biological traces left on these substrates as biosignatures.
The positive impact of honeybee activity on fennel crop production and sustainability
Authors: Ali Mahmoud Abbas , Al-Farga Ammar , Seddik M. A.
Published: June 2024

This study investigates the ecological interaction between honeybees (Apis mellifera) and fennel (Foeniculum vulgare) plants, examining the mutual benefits of this relationship. Field experiments conducted in Egypt from December 2022 to May 2023 recorded diverse insect pollinators attracted to fennel flowers, especially honeybees. Assessing honeybee colonies near fennel fields showed improvements in sealed brood (357.5–772.5 cells), unsealed brood (176.3–343.8 cells), pollen collection (53.25–257.5 units), honey accumulation (257.5–877.5 units), and colony strength (7.75–10) over three weeks. Fennel exposure explained 88–99% of variability in foraging metrics. Comparing open versus self-pollinated fennel revealed enhanced attributes with bee pollination, including higher flower age (25.67 vs 19.67 days), more seeds per umbel (121.3 vs 95.33), bigger seeds (6.533 vs 4.400 mm), heavier seeds (0.510 vs 0.237 g/100 seeds), and increased fruit weight per umbel (0.619 vs 0.226 g). Natural variation in seed color and shape also occurred. The outcomes demonstrate the integral role of honeybees in fennel agroecosystems through efficient pollination services that improve crop productivity and quality. Fennel provides abundant nutritional resources that bolster honeybee colony health. This research elucidates the symbiotic bee-fennel relationship, underscoring mutualistic benefits and the importance of ecological conservation for sustainable agriculture.
Synthesis of nickel-sphere coated Ni-Mn layer for efficient electrochemical detection of urea
Authors: Ezzat Nourhan , Hefnawy Mahmoud A. , Fadlallah Sahar A. , El-Sherif Rabab M. , Medany Shymaa S.
Published: June 2024

Using a trustworthy electrochemical sensor in the detection of urea in real blood samples received a great attention these days. A thin layer of nickel-coated nickel-manganese (Ni@NiMn) is electrodeposited on a glassy carbon electrode (GC) (Ni@NiMn/GC) surface and used to construct the electrochemical sensor for urea detection. Whereas, electrodeposition is considered as strong technique for the controllable synthesis of nanoparticles. Thus, X-ray diffraction (XRD), atomic force microscope (AFM), and scanning electron microscope (SEM) techniques were used to characterize the produced electrode. AFM and SEM pictures revealed additional details about the surface morphology, which revealed a homogenous and smooth coating. Furthermore, electrochemical research was carried out in alkaline medium utilizing various electrochemical methods, including cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). The electrochemical investigations showed that the electrode had good performance, high stability and effective charge transfer capabilities. The structural, morphological, and electrochemical characteristics of Ni@NiMn/GC electrodes were well understood using the analytical and electrochemical techniques. The electrode showed a limit of detection (LOD) equal to 0.0187 µM and a linear range of detection of 1.0–10 mM of urea. Furthermore, real blood samples were used to examine the efficiency of the prepared sensor. Otherwise, the anti-interfering ability of the modified catalyst was examined toward various interfering species.