AUTHOREA
Log in Sign Up Browse Preprints
LOG IN SIGN UP

Preprints

Explore 41,474 preprints on the Authorea Preprint Repository

A preprint on Authorea can be a complete scientific manuscript submitted to a journal, an essay, a whitepaper, or a blog post. Preprints on Authorea can contain datasets, code, figures, interactive visualizations and computational notebooks.
Read more about preprints.

Augmenting OAuth 2.0 for securing Internet of Things
Sheetal Kalra
* Jyoti

Sheetal Kalra

and 2 more

November 16, 2023
Internet of things(IoT) has made human life more convenient by adding millions of devices.As the number of smart devices increases so is the concern towards security of these devices as well as towards the systems attached to these devices. OAuth is widely used authentication and authorization protocol used on the internet.This article makes augmentation in OAuth by proposing personal authorization server.It provides secure access to the information on IoT devices. The smartphone that communicate with the servers to transmit information on IoT devices can be the OAuth authorization server. Personal OAuth proposed by this article issues the access token when OAuth authorization server registers with the client firstly. Personal authorization server is very much trustworthy than third party. It makes a secure IoT environment. Performance of the proposed scheme is measured in terms of processing time in seconds and gives very good results.
Chiral dual-core AIEgens based-on through-space coupling for high-performance organic...
Lifen  Chen
Mingjia  Deng

Lifen Chen

and 9 more

November 16, 2023
In this work, we demonstrate a chiral dual-core strategy for the design of high-performance organic circularly polarized aggregation-induced emission luminogens (AIEgens), which features of connecting two thermally activated delayed fluorescence (TADF) luminophore with chiral linkage that allows efficient through-space coupling (TSC) to occur. Using this strategy, a pair of dual-core enantiomers, R/S-DNKP, were designed and synthesized by linking two benzophenone derivatives with a 1,1’-bi-2-naphthol unit. Compared to the mono-core counterpart NKP, the dual-core emitters exhibited a much higher photoluminescence quantum yields of 94%. Moreover, benefited from their chiral helical folding configurations, the R/S-DNKP enantiomers exhibited a high luminescence dissymmetry factor (|glum|) value up to 1.3×10-3 in film states. Notably, the electroluminescence devices based on the R/S-DNKP enantiomers achieved external quantum efficiency values of 21.5% and 19.7% with little roll-off. It is believed that this molecular design strategy will pave new routes for the development of high-performance chiral emitters for future organic photonic devices.
Application and Parameterization of a 1D Multifluid Population Balance Model to Bubbl...
Ferdinand Breit
Christian Weibel

Ferdinand Breit

and 2 more

November 16, 2023
A 1D multifluid population balance model approach is presented as a compromise between computational effort and accuracy. The approach is used to test process scenarios, perform sensitivity analysis, and provide a reliable scale-up and optimization tool. The study focuses on a mini-plant batch bubble column, where the scale-up behavior in terms of bubble column height, gas flux, and composition of the liquid phase is investigated. Although simplifications were made, the model requires calibration to experimental data using different calibration methods. An optimal calibration procedure is found that minimizes experimental effort while maximizing scalability. The model was tested on various liquid-phase compositions, and it was found to reproduce experimental data accurately. However, the model cannot reproduce flow regime changes and does not perform well outside the calibrated concentration. The study shows that the applied 1D multifluid populations balance approach is a valuable and reliable tool in multiphase reactor scale-up and optimization.
Investigation of Taylor Bubble Behavior in Upward and Downward Vertical and Inclined...
Ahmed Aql
Eissa Al-Safran

Ahmed Aql

and 1 more

November 16, 2023
Taylor bubble dynamics in two-phase flow are vital for many engineering applications, impacting momentum, heat, and mass transfer efficiencies. Grasping these dynamics is key for reactors, pipelines, and enhanced oil recovery system designs. In slug flow, the movement of liquid slugs and Taylor bubbles is defined by the Taylor bubble velocity, influenced by the flow distribution coefficient (C0). This research collates a vast database of Taylor bubble velocity and C0 at different flow inclination angles, assesses current models, and introduces a unified C0 model. It’s observed that the physics of the flow distribution coefficient in downward flow differs significantly from upward flow. Overall, C0 experiences two transitions influenced by pipe inclination. The new model successfully represents this behavior in different inclination angles, including downward flow. Validation shows that the model outperformed existing ones, having an average error of 4.75% and a standard deviation of 8.03%.
Distribution network differential protection scheme based on improved feature mode de...
磊 王
鑫 宋

磊 王

and 2 more

November 16, 2023
Cutting off single-phase ground faults in distribution networks within the required time frame has always posed a challenging problem when selecting low-current grounding lines. With advancing communication technology, optical fiber and 5G costs continue to decrease, allowing for more convenient and quicker data transmission. As a result, various methods can be employed using signal waveforms to achieve distribution network differential protection.In this paper, we propose a new adaptive differential protection scheme that employs improved feature mode decomposition through the whale optimization algorithm to decompose zero-sequence current waveforms collected at both ends of the line. Based on the fundamental principle of current differential protection, we conduct similarity analysis using the most critical fault characteristic component. This approach effectively resolves the issue of inadequate grounding current in the distribution network, ensuring the differential protection device meets operational requirements and guarantees safe and stable system operation.Finally, simulation verification using MATLAB software validates the effectiveness of this scheme and verifies its accuracy under different fault conditions.
Role of organic additives in the preparation of polyetherimide membranes for solvent...
Yuan Zhang
Beibei Luo

Yuan Zhang

and 3 more

November 16, 2023
The incorporation of non-solvent organic additives in the casting solution has emerged as a significant technique in membrane fabrication. This approach enables the manipulation of membrane morphology and facilitates the preparation of high-performance membranes. Our work focusing on investigating the impact of various organic additives on the development of integrally skinned polyetherimide asymmetric nanofiltration membranes, which has not been explored in solvent resistant nanofiltration (SRNF). The additives investigated in this study can be classified into three categories: hydrophilic monomers, hydrophilic polymer and surfactant additives. The effect of these organic additives on PEI membrane performance was evaluated by separating methylene blue (MB, molecular weight 374 Da) from ethanol solution, and membrane morphology was characterized by scanning electron microscope (SEM).
Applications of the p53/MicroRNA-34 axis beyond cancer
James Schwartzberg

James Schwartzberg

and 1 more

November 16, 2023
Human life is seriously threatened by cancer. Long years of study and data collecting have led to a growing body of knowledge about cancer and its treatment. The p53 gene is crucial as a tumor suppressor. With the more in-depth study of the structure and function of p53, the greater relevance of this tumor suppressor gene is understood in the process of suppressing tumor development. Non-coding RNAs (ncRNAs) such microRNAs (miRNAs) that are about 22 nucleotides in length play a crucial role in tumor initiation, progression, and metastasis. In the fight against cancer, miR-34 has emerged as a key player. Tumor development, metastasis, and tumor stem cell maintenance may all be stymied by the regulatory network created by p53 and miR-34. This article summarizes recent developments in our understanding of the p53/miR-34 regulation network and its potential utility in the detection and treatment of cancer.
New therapeutic axis in blood malignancies involving microRNAs and JAK/STAT3 signalin...
George House

George House

November 16, 2023
Cancers of the blood stemming from genetic or environmental abnormalities are included in the broad category of blood diseases. Some forms of leukemia may respond better to therapy than others, and there are a number of factors that contribute to the failure of current medications to effectively address blood diseases, including drug resistance. Many different factors, both inherited and acquired, may cause leukemia, which is characterized by the uncontrolled growth of one or more cell lines. Oncogene signal transducer and activator of transcription (STAT) family transcription factor STAT3, in particular, plays a crucial role in the initiation and development of hematological illnesses as a result of mutations, malfunction, or hyperactivity. In addition, research indicates that microRNAs, as biological molecules, may promote or inhibit tumor growth in different types of cancer. Additionally, it has been found that STAT3 has a robust connection to miRNA. For example, miRNAs may control STAT3 by targeting its upstream mediators such as IL6, IL9, and JAKs or directly binding to the STAT3 gene. However, STAT3 has the ability to control miRNAs. The purpose of this review was to identify the function of microRNAs and STAT3 and how they interact with one another in hematological malignancies.
Transcriptomic insights into the development and therapy of breast cancer via the ncR...
Jim Al Khaled

Jim Al Khaled

November 16, 2023
Several studies, made possible by the rapid development of next-generation sequencing technology, have shown that ncRNAs can act as competitive endogenous RNAs (ceRNAs) and are involved in a variety of biological processes, including the proliferation, differentiation, apoptosis, and migration of breast cancer (BC) cells, playing an important role in BC progression as a molecular target for its diagnosis, treatment, prognosis, and differentiation of subtypes and age groups of BC patients. This study screened and ranked the sequencing analysis and experimental verification conclusions of BC-related ceRNAs based on the description of ceRNA-related biological functions and found that the ncRNAs mediated ceRNA networks can promote the development of BC by promoting the expression of genes related to BC proliferation, drug resistance, and apoptosis; inducing the production of epithelial-mesenchymal transition (EMT) to promote metastasis; and activating cancer-related microRNAs. 1. Background Breast cancer (BC) is characterized by a wide range of phenotypes and genetic backgrounds. Surgery, radiation therapy, and chemotherapy are all often used to treat BC; nevertheless, the disease is difficult to cure since it frequently returns, spreads to other parts of the body, and develops resistance to drugs. To better the clinical treatment efficacy, early diagnosis rate, and prognosis of BC patients, it is crucial to identify novel therapeutic targets and diagnostic and prognostic biomarkers [1, 2, 3, 4]. Endogenous non-coding RNAs (ncRNAs) have garnered a lot of attention due to their regulatory roles in a wide range of biological processes, and their discovery has coincided with the gradual unveiling of complex genetic changes in BC made possible by the rapid development of transcriptomics and the cross-application of bioinformatics and big data science. Their identification has also considerably boosted efforts to identify therapeutic targets unique to BC. The mechanism of action of these recently found molecules in the process of BC remains unknown and is not able to give support for the diagnosis or treatment of BC, despite the fact that tremendous progress has been achieved in the creation of therapeutic methods and medications targeting BC [5]. Therefore, there has been a lot of effort put into trying to figure out how these ncRNAs are regulated both pre-and post-transcriptionally. Studies have demonstrated that ncRNAs, such as long non-coding RNAs (lncRNAs), circulatory RNAs (circRNAs), microRNAs (miRNAs), and messenger RNAs (mRNAs) are improperly produced in a range of malignancies, including BC [6], and play a significant role in post-transcriptional regulation [7]. In addition, these compounds are associated with BC development, spread, and resistance to treatment [8]. Nonetheless, they have further use as indicators for BC patient prognosis, categorization, and staging [9]. As further research has shown [10],
Nano-therapeutic targeting of the tumor microenvironment in metastatic breast cancer:...
Aksel Hansen

Aksel Hansen

and 2 more

November 16, 2023
The tumour-microenvironment (TME) is a complex network of cells and molecules that has a major impact on the development, dissemination, and progression of cancer metastasis. It is made up of stromal cells, tumour cells, cancer-associated blood and lymphatic vessels, pericytes, cancer-associated fibroblasts, cancer-stem cells, and extracellular matrix (ECM). Metastatic breast cancer is one of the most difficult to treat forms of the disease. This calls for a comprehensive comprehension of the metastatic TME and the development of novel nano-drug delivery systems that leverage specific cellular components. Nanoparticles (NPs) that respond to external stimuli provide improved control over where and when cells are targeted. Nano-therapies need to be safe, effective and scalable in manufacturing for translation to clinics. Emerging nano-strategies, in contrast to traditional medicines that promote systemic ablation, selectively control the diverse TME cell populations by, for example, focusing on pericytes and endothelial cells to normalize vascular function. We also describe the gaps in the present nanotherapeutics approaches and highlight innovative views on the design of pre-clinical and clinical trials to alter breast cancer's ability to spread.
Unmanned Ground Vehicle for High-throughput Phenotyping to Quantify Field Crops Chara...
Keshav Singh

K.D. Singh

and 12 more

November 15, 2023
Digital imaging technology has gained significant interest in recent decades, particularly in the field of high-throughput phenotyping (HTP) for plant breeding. Breeding programs generates thousands of new crop lines that require evaluation under multiple environments. Considerable efforts have been made in utilizing genome wide association studies (GWAS) and genomic selection (GS) to identify genetic markers and improve desirable crop characteristics. Selecting key phenotypes is an essential component of plant breeding, and traditional methods require considerable resources and are subjective. Therefore, breeders and geneticists are in an urge of a robust technology to identify desirable crop traits. HTP using advanced sensors is a promising approach to evaluate improved crop genotypes for traits of agronomic importance. In this project, six Research and development Centers (RDCs) of Agriculture and Agri-food Canada have been utilizing University of Saskatchewan built Field Phenotyping System ("UFPS Cart") to phenotype a heritage bread wheat panel. The UFPS cart is a proximal sensing mobile platform equipped with multiple payloads (RTK GPS, RGB, NIR, and LiDAR sensor). For diverse climatic data collection, the panel consisting of 30 Canadian western spring wheat varieties were grown under six environments. This study aims to develop large-scale data management and image analysis pipelines to quantify different crop growth characteristics representing agronomic and physiological traits. It support data-driven decision making under genotype × environment effect. The multi-location imagery and ground observation data from six environments are currently being processed using the internal General Public Science Cluster (GPSC) for deep learning training to develop prediction models and extract phenotypic traits of interest (canopy height, crop lodging, heading, maturity, grain yield and protein content). The developed tools and associated models will aid to accelerate advances in cereal breeding programs.
PEYER'S PATCHES, BISPHENOL A INGESTION AND SELENIUM SUPPLEMENTATION IN MURINE MODELS.
João  Araújo
Clarisse Fonseca

João Araújo

and 8 more

November 15, 2023
Bisphenol A [2,2-bis(4hydroxyphenyl) propane, BPA], one of the endocrine disruptors, is of great concern due to its widespread use throughout the world. Several studies have shown that BPA has toxic effects when ingested, making contact with this substance a risk factor for the development of diseases in various organs, including the intestine and associated lymphoid tissue. Therefore, the objective of this work was to study the morphology of Peyer’s patches in young rats supplemented with selenium and exposed to BPA. The study was approved by the UFPI Animal Use Ethics Committee, with protocol number 583/19. 28 male Wistar rats ( Rattus novergicus albinus) were randomly divided into 4 groups: Control (CT), BPA, Se and BPA+Se. The pups were weaned on the 21st day and, from the 22nd postnatal day, the animals in the BPA group received daily doses of 5 mg/kg of BPA diluted in 0.3 ml of corn oil, administered orally. The Se group received 10 μg/kg of Se, the BPA+Se group received 5 mg/kg of BPA and 10 μg/kg of Se and the CT group did not receive any substance but was subjected to the oral gavage process. After 4 weeks of exposure, the puppies were anesthetized and euthanized for intestinal collection and subsequent histological, immunohistochemical and morphometric analysis. Our results showed that BPA caused damage to the epithelial layer of Peyer’s patches, there was a structural disarray in the architecture of the follicular region of the BPA and BPA+Se groups, zones of inflammation with the presence of vacuoles in the tissue. A reduction in Ki-67 expression in Peyer’s patches was also observed in the BPA group, as well as a significant reduction in the number of defense cells in the group. Animals exposed to BPA, but supplemented with Se, showed no damage to the epithelial layer and there was no reduction in Ki-67 expression. BPA, when ingested above the safe level, altered Peyer’s patches tissue, and reduced cell proliferation. Additionally, BPA reduced the immune cell population in Peyer’s patches. Se was able to reverse the observed damage, suggesting antioxidant potential.
Automated Segmentation of Cell Organelles in volume electron microscopy using Deep Le...
Nebojša Nešić
Xavier Heiligenstein

Nebojša Nešić

and 12 more

November 15, 2023
Recent advances in computing power triggered the use of Artificial Intelligence in image analysis in life sciences. To train these algorithms, a large enough set of certified labelled data is required. The trained neural network is then capable of producing accurate instance segmentation results, that will then need to be re-assembled into the original dataset: the entire process requires substantial expertise and time to achieve quantifiable results. To speed-up the process, from cell organelle detection to quantification across modalities, we propose a deep learning based approach for Fast AutoMatic Outline Segmentation (FAMOUS), that involves organelle detection combined with image morphology, and 3D meshing to automatically segment, visualize and quantify cell organelles within volume electron microscopy datasets. From start to finish, FAMOUS provides full segmentation results within a week on previously unseen datasets. FAMOUS was showcased on a dataset acquired using a focused ion beam scanning electron microscope (FIBSEM), and on yeast cells acquired by transmission electron microscopy.
Effect of zamicastat on blood pressure and heart rate response to cold pressor test:...
Marlene Fonseca
Cheila Ribeiro

Marlene Fonseca

and 9 more

November 15, 2023
Aim: Inhibitors of dopamine-β-hydroxylase (DβH), such as zamicastat, emerged as promising drugs for pulmonary arterial hypertension (PAH). This study intended to validate the mechanism of action of zamicastat by studying its effect on the overdrive of sympathetic nervous system (SNS). Methods: This was a single-centre, prospective, double-blind, randomised, placebo-controlled, crossover study, with 400 mg zamicastat, in 22 healthy male subjects. Cold pressor test (CPT) was performed at screening and each treatment period at day 1 and day 10. The concentration of dopamine (DA), epinephrine (EPI), norepinephrine (NE) in plasma and 24h-urine, and DβH activity in plasma were measured. Results: For zamicastat compared to placebo, the difference between cold stimulus and rest phases on the change from baseline to day 10 of CPT showed an estimated decrease of -4.62 mmHg for systolic blood pressure (SBP; p=0.020). Zamicastat caused a decrease of -2.62 mmHg in mean arterial pressure (MAP) response to cold stimulus during CPT (p=0.025). At day 10, zamicastat elicited a statistically significant increase of 12.63 ng/L (p=0.040) and 19.22 ng/L (p=0.001) in plasma DA, before CPT and after CPT, and a significant estimated increase in plasma EPI change from baseline after CPT (p=0.040). Inhibition of plasma DβH activity ranged from 19.8% to 25.0%. At day 10, statistically significant reductions in 24-hour urinary excretion of EPI (p=0.002) and NE (p=0.001) were observed. Conclusions: Zamicastat decreased SBP and MAP response to cold stimulus during CPT, evidencing its effect on the overdrive sympathetic response to cold stimulus.
”Comment on: [ Role of regional anesthesia in patients with acute sickle cell pain: A...
Adeeb Oweidat
Anil A. Marian

Adeeb Oweidat

and 3 more

November 15, 2023
Adeeb Oweidat MD, DESAIC, EDRA
Fertility Preservation in Pediatric Solid Tumors: A Report from the Children’s Oncolo...
Kari Bjornard
Allison Close

Kari Bjornard

and 5 more

November 15, 2023
Treatment for childhood solid tumors may lead to an increased risk for gonadal dysfunction/infertility. Discussion of risk should occur at diagnosis, any changes in therapy, and during survivorship. Gonadotoxic therapies were abstracted from 32 Children’s Oncology Group (COG) phase III, frontline solid tumor protocols, in use from 2000-2022. Risk for gonadal dysfunction/infertility was assessed based on gonadotoxic therapies, sex, and pubertal status and assigned as minimal, significant, and high following the Oncofertility Consortium Pediatric Initiative Network (PIN) risk stratification. Most protocols (65.6%, 21/32) contained at least one therapeutic arm with a high level of increased risk. Solid tumor therapies present challenges in risk stratification due to response-adjusted therapy and the need to account for radiation field in the risk assessment. This guide hopes to serve as a tool to assist in standardizing gonadotoxic risk assessments across disciplines and improve referral for fertility services and reproductive health counseling for patients receiving COG based solid tumor therapy.
Changing clinical characteristics of pediatric inpatients with pneumonia during COVID...
Mengxue Chen
Yabing Zhou

Mengxue Chen

and 13 more

November 15, 2023
Background: The COVID‐19 pandemic have impacts on the prevalence of other [pathogen](javascript:;)s and people’s social lifestyle. This study aimed to compare the [pathogen](javascript:;), allergen and micronutrient characteristics of pediatric inpatients with pneumonia prior to and during the COVID-19 pandemic in a large tertiary hospital in Shanghai, China. Methods: Patients with pneumonia admitted to the Department of Pediatric Pulmonology of Xinhua Hospital between March-August 2019 and March-August 2020 were recruited. And clinical characteristics of the patients in 2019 were compared with those in 2020. Results: Hospitalizations for pneumonia decreased by 74% after the COVID-19 pandemic. For [pathogen](javascript:;)s, virus, mycoplasma pneumoniae (MP) and mixed infection rates were all much lower in 2020 than those in 2019 ( P < 0.01). Regarding allergens, compared with 2019, the positive rates of house dust mite, shrimp and crab were significantly higher in 2020 ( P < 0.01). And for micronutrients, the levels of vitamin B2, B6, C and 25-hydroxyvitamin D (25(OH)D) in 2020 were observed to be significantly lower than those in 2019 ( P < 0.05). For all the study participants, longer hospital stay (OR = 1.521, P = 0.000), milk allergy (OR = 6.552, P = 0.033) and [calcium](javascript:;) (Ca) insufficiency (OR = 12.048, P = 0.019) were identified as high-risk factors for severe pneumonia by multivariate analysis. Conclusions: The number of children hospitalized with pneumonia and incidence of common pathogen infections were both reduced, and that allergy and micronutrient status in children were also changed after the outbreak of the COVID-19 pandemic.
Improving Authorization With Colour-based ID Card Detection
Nikitha K R
Harini Murugan

Nikitha K R

and 3 more

November 15, 2023
ChromaCard represents an automated apparatus designed for the authentication of access to a given location based on the coloration of an individual’s ID card tag. In contrast to conventional systems reliant upon ID card readers, which necessitate manual interaction to present the tag to the device, our innovative robotic solution excels in seamlessly detecting tag colours even when in motion. Employing a sophisticated camera equipped with object detection capabilities, the robotic entity rigorously scrutinizes the hues of the ID tag. Subsequently, it cross-references this data with a comprehensive repository of validated ID cards authorized for entry to the specified location at the given moment. The determination of an individual’s entitlement to access is thereby made, leading to one of two outcomes: should authorization be affirmed, the robotic system proceeds to assess the subsequent ID card; conversely, if access is denied, it promptly dispatches a notification to the student care administrator, who is near the facility.
Revealing Popping Mechanics of Popcorn using ITRAQ-based Proteome Profiles
Yongbin Dong
Qi Zheng

Yongbin Dong

and 8 more

November 15, 2023
Popcorn is a special kind of maize that can easily become popcorn flake when heated under a given condition. However, its popping mechanism remains unclear at present. Opaque2 (O2) was a central transcriptional factor that play important roles during maize endosperm development. In this study, an o2 introgression into N04 inbred line was constructed, and the mutation of o2 reduced the popping rate of N04. In order to reveal the underlying mechanism of O2 involved in popping characteristics, the o2 introgression and popcorn inbred line N04 were performed proteomic analysis at three development stage of their kernels using the 8-plex iTRAQ reagents with three repetitions followed by 2D-LC-MS/MS spectra. A total of 5184 proteins were found, and 1073 proteins of which showed dynamics change. KEGG enrichment analysis found that these dynamic changed proteins were significantly enriched in carbon metabolism, pyruvate metabolism, citrate cycle, fructose and mannose metabolism, starch and sucrose metabolism, and pentose phosphate pathway. A total of 16 differentially expressed protein regulated by O2 were identified. These results preliminary uncover the molecular mechanism of popping characteristics in popcorn.
Not About U: Social Dissonance at a Land-Grab University
Richard Finlay Fletcher

Richard Finlay Fletcher

November 15, 2023
Mattin’s concept of social dissonance and durational concert Social Dissonance offer compelling devices to understand a central tension within institutions of higher education in settler colonial contexts. How can faculty and students support unlearning gestures in their shared work at a ‘Land-grab’ university, a term used in a 2020 report to describe how ‘Land-grant’ institutions created through the federal 1862 Morrill Act were founded the forced expropriation of Indigenous land and life? This article mixes the settler author’s repeated experiences of Social Dissonance at documenta 14, in both Athens, Greece, and its traditional home of Kassel, Germany with its translation to a sequence of teaching contexts at the ‘Land-grab’ university where he works. Amid failures to prevent a rightwing power-grab and create curriculum on global Indigenous arts, the author turns to the concept of social dissonance as a timely heuristic for revealing the levels of a specifically colonial intrusion into educational contexts by an exclusionary settler worldview. At the same time, the author attempts to tune out this colonial noise by gesturing towards echoes of the Social Dissonance in the vital work of living, Indigenous artists.
Streamflow extremes alter air-water relationships in South American river-floodplain...
Christine Lucas
Leticia de Los Santos

Christine Lucas

and 6 more

November 01, 2023
Extreme hydroclimate events affect the thermal regimes of freshwater systems. In a four-year period spanning periods of flooding and severe drought in Southeastern South America (2019-2023), we monitored temperature variability in streams and floodplain lakes in an undammed tributary of the Lower Uruguay River, using Onset HOBO dataloggers and modeled daily streamflow (Q). We compare the performance of linear and nonlinear regression and generalized additive models (GAM) to evaluate how air temperature (T air) variability affects water temperature (T water) at daily, weekly and monthly time scales and under different Q percentile ranges. Mean daily temperatures ranged from 6.4ºC to 30.2ºC with daily maxima coinciding with record highs >40 ºC in T air and record low streamflow in summer months. Daily and weekly air-water relationships for rivers, streams and lakes were best fit by nonlinear sinusoidal models (Nash Sutcliffe Error - NSE ≥ 0.68). Extremely low-flow periods (<10% Q) showed a linear relationship to T air, while high-flow periods (>90%) showed a nonlinear sinusoidal air-water relationship. Moreover, high-flow events showed weaker T air-T water model perforamce than moderate to low flow periods. Preliminary comparisons between basin land-cover and T water suggest that forest cover favors lower T min. This study fills a geographical gap in thermal regime data in freshwater ecosystems in South America and suggests that extreme hydroclimate events have important implications for the thermal behavior of freshwater systems.
Could hybridization increase establishment success of the biological control agent Ap...
Andrew Yoshimoto
Marianna Szucs

Andrew Yoshimoto

and 1 more

November 15, 2023
Intraspecific hybridization between distinct populations could increase fitness and adaptive potential of biological control agents that often have low genetic diversity and can be inbred due to long-term laboratory rearing often at small population sizes. Hybridization can also alter host preference and performance when the parental insect populations are adapted to different host plants. We investigated the effects of hybridization between two populations (Northern and Southern) of the psyllid, Aphalara itadori, that have different fitness on three invasive knotweed species (Japanese, giant, and Bohemian). Fecundity, host choice, and developmental success of second-generation reciprocal hybrids and the parental psyllid populations were compared on the three knotweed species in multiple choice tests. Hybridization did not increase fecundity. All three knotweed species were accepted for oviposition without preference by the Southern and the two hybrid psyllid populations. The northern psyllid population laid the most eggs on Bohemian knotweeds but those were maladaptive choices since almost all eggs failed to develop. Developmental success of the parental psyllid populations was highest on the knotweed species they were originally collected from, on Japanese knotweed of the Southern psyllids and on giant knotweed of the Northern psyllids. Hybrids had intermediate or higher survival on given knotweed hosts compared to their parents. These results can inform release tactics of A. itadori in different regions especially where there appears to be climatic and/or host mismatches such as in Michigan. In southern Michigan, based on climate the Northern psyllid population should be released. However, the most common knotweed species in the region are Bohemian and Japanese knotweeds that do not support development of the Northern psyllids. In this case, hybrids that may carry cold adaptations of the Northern psyllids but have better developmental success on the prevailing knotweed species may be considered for release to increase establishment success.
Tips for a Buying Furniture for Your Home A. Consider Your Space
Bellot Twig

Bellot Twig

November 16, 2023
A document by Bellot Twig. Click on the document to view its contents.
The long and tortuous path towards improving photosynthesis by engineering elevated m...
Alistair Leverett
jk417

Alistair Leverett

and 1 more

November 16, 2023
The growing demand for global food production is likely to be a defining issue facing humanity over the next 50 years. In order to tackle this challenge, there is a desire to bioengineer crops with higher photosynthetic efficiencies, to increase yields. Recently, there has been a growing interest in engineering leaves with higher mesophyll conductance (gm), which would allow CO2 to move more efficiently from the substomatal cavities to the chloroplast stroma. However, if crop yield gains are to be realised through this approach, it is essential that the methodological limitations associated with estimating gm are fully appreciated. In this review, we summarise these limitations, and outline the uncertainties and assumptions that can affect the final estimation of gm. Furthermore, we critically assess the predicted quantitative effect that elevating gm will have on assimilation rates in crop species. We highlight the need for more theoretical modelling to determine whether altering gm is truly a viable route to improve crop performance. Finally, we offer suggestions to guide future research on gm, which will help mitigate the uncertainty inherently associated with estimating this parameter.
← Previous 1 2 … 7 8 9 10 11 12 13 14 15 … 1728 1729 Next →

| Powered by Authorea.com

  • Home