bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional characterization of the Escherichia coli membrane transport protein MdtEF
Authors: Tong Chunyu , Liang Yimin , Liu Qi , Feng Wenzhi , Yu Honghao , Song Bocui 
Published: April 2024

Abstract

The mdtE and mdtF genes encode membrane transporters, with their transport substrates and mechanisms still not fully understood. Amino acid sequence analysis suggests that MdtE belongs to the MFP family while MdtF belongs to the RND family. MdtF is positioned in the inner membrane, while MdtE is found in the periplasmic space, connecting MdtF with the outer membrane porin TolC to create a MdtEF-TolC tripartite efflux pump for drug and substrate efflux. Subsequently, an Escherichia coli (E. coli) mdtEF gene deletion strain was developed using a suicide plasmid method. An expression vector, was then constructed and complemented based on the pBR322 vector. Drug sensitivity tests and EB accumulation experiments were performed on the mdtEF gene deletion strain, revealing that the MdtEF protein could efflux the carbapenems imipenem and ertapenem. In the EB accumulation experiment, two inhibitors, vanadate and carbonyl m-chlorophenylhydrazone (CCCP), were utilized, demonstrating that MdtEF functions through the proton gradient's potential energy for substrate transport.
Object-Oriented Multi-Scale Segmentation and Multi-Feature Fusion-Based Method for Identifying Typical Fruit Trees in Arid Regions Using Sentinel-1/2 Satellite Images
Authors: Liang Jiaxi , Sawut Mamat , Cui Jintao , Hu Xin , Xue Zijing , zhao Ming , Zhang Xinyu , Rouzi Areziguli , Ye Xiaowen , Xilike Aerqing 
Published: April 2024

Abstract

The rapid and accurate identification of fruit trees provides a foundation for dynamic monitoring of orchard planting areas and estimating orchard yields objectively. This study aims to evaluate the applicability of time series Sentinel-1/2 satellite data for fruit tree classification and to provide a new method for accurately extracting fruit tree categories. Therefore, the study area selected is the Tarim Basin, the most important fruit-growing region in northwest China. The main focus is on the identification of three major fruit tree species in this region. Time series Sentinel-1/2 satellite images acquired from the Google Earth Engine (GEE) platform are used for the study. A multi-scale segmentation approach is applied, and six categories of features including spectral, phenological, texture, polarization, vegetation index, and red edge index features are constructed. A total of 44 features are extracted and optimized using the Vi feature importance index to determine the best time phase. Based on this, an object-oriented segmentation combined with Random Forest (RF) method is used to identify fruit tree categories. The results are compared with three other commonly used traditional machine learning algorithms, including Classification and Regression Tree(CART), Gradient Boosting Decision Tree(GBDT), and Support Vector Machine(SVM)classification methods, to determine the best approach for fruit tree identification. The results show that: (1) the object-oriented segmentation method helps to improve the accuracy of fruit tree identification features; September satellite images provide the best time window for fruit tree identification, with spectral, phenological, and texture features contributing the most to fruit tree category identification; (2) the RF model has a higher accuracy in identifying fruit tree categories than other machine learning models, with an Overall Accuracy (OA) and Kappa Coefficient(KC) of 94.60% and 93.74% respectively, indicating that the combination of object-oriented segmentation and RF algorithm has great value and potential for fruit tree identification and classification. This method can be applied to large-scale fruit tree remote sensing classification and provide an effective technical means for monitoring fruit tree planting areas using medium to high-resolution remote sensing images.
Parafoveal Preview Effects in Chinese Reading Comprehension among Third- and Fifth-graders: The Role of Phonetic Radicals
Authors: Luo Jiefei , Qin Ruiqi , Wu Yan 
Published: April 2024

Abstract

This eye-movement study utilizing the boundary paradigm investigated the processing of phonological information in the parafoveal during reading in Chinese children from third and fifth grades. The experimental design required participants to read sentences that included regular, irregular, homophone, or unrelated control phonograms as substitutes for normal simple characters. Both regular and irregular characters incorporated the same simple character as their phonetic radical, but only regular characters shared the exact pronunciation with their corresponding phonetic radical. The preview benefit of phonetic radicals was assessed by comparing regular and irregular characters against the unrelated control condition. In contrast, the preview benefit of homophones was determined by contrasting visually dissimilar homophones with the unrelated control condition. Results revealed that the phonetic radical preview effect becomes evident in the initial stages of reading for fifth graders. Subsequently, in the later integration stage, regular characters, wherein the phonetic radical's pronunciation consistent with the host character, demonstrate a markedly enhanced preview benefit compared to irregular characters. Notably, the homophone preview effect, emerging after the phonetic radical preview effect, maintains consistency among fifth-grade readers, in contrast to third-grade readers. These outcomes underscore the pivotal role of phonological information in the reading development of Chinese children, with effects varying across different grades.
Effects of acute aerobic exercise on sweet taste preference and its brain mechanisms in tobacco addicts
Authors: Liu Hongen , Han Yanbai , Liang Wei , Zhou Lin , Zhang Yingying , Sun Pinghan , Fan Hainan , Xu Zhao 
Published: April 2024

Abstract

Aerobic exercise can improve cravings for smoking and inhibition control in tobacco-dependent individuals; however, its effect on their sweet taste preferences remains unclear. This study aims to examine the effects of acute aerobic exercise on sweet taste preferences and nerve sensitivity in brain regions associated with the prefrontal cortex in tobacco-dependent subjects. Participants were asked to perform 35 minutes of exercise or rest. They took the sweet taste preference test and the Visual Food Cues Paradigm Task immediately before and immediately after the experiment. After the intervention with acute high-intensity exercise, participants' preference for low-sweetness foods increased significantly (F = 14.220, P < 0.001). Following the moderate-intensity exercise intervention, when participants were shown pictures of low-sweetness food, the average concentration of oxyhemoglobin in the right orbitofrontal cortex increased significantly (F = 14.215, P < 0.001). Additionally, the change in functional connection strength between the right dorsolateral prefrontal cortex and the left ventrolateral prefrontal cortex was significantly enhanced (F = 4.113, P = 0.046). These results suggest that acute aerobic exercise can alter the sweet taste preferences of tobacco-dependent subjects, as well as the level of PFC activation and functional connectivity, thereby temporarily restoring the nerve sensitivity related to sweet taste that has been impaired by nicotine.
Effects of Hurricane Irma on mosquito abundance and species composition in a metropolitan gulf coastal city, 2016-2018
Authors: Moise Imelda K. , Huang Qian , Medina Johana , Petrie William D. 
Published: April 2024

Abstract

Mosquitoes are the most common disease vectors worldwide. Rainfall variability and the frequency of rainfall events might be important factors influencing environmental conditions, the mosquito life cycle and mosquito population dynamics, particularly post storming events. We examined mosquito abundance and species composition before and after Hurricane Irma in Miami, Dade County, Florida, and identified which mosquito species predominated post-Hurricane Irma according to trap type. Our results showed that more mosquitoes (7.3 and 8.0 times more) were captured in 2017 than at baseline (2016 and 2018). The responses of different mosquito species to the possible effects of Hurricane Irma varied: in BG-Sentinel traps, 3 of the 13 species (Aedes tortills, Culex nigripalpus and Culex quinquefasciatus) and in CDC light traps, 7 of the 20 species (Aedes tortills, Anopheles atropos, Anopheles crucians, Anopheles quadrimaculatus, Culex erraticus, Culex nigripalpus, and Psorophora columbiae) dominated pre-post Hurricane Irma. The risk factors for mosquito abundance were population density, rainfall, and temperature. This may further our understanding of the relationships between the amount of rainfall and other underlying factors affecting mosquito abundance.
An attentional mechanism model for segmenting multiple lesion regions in the diabetic retina
Authors: Xu Changzhuan , He Song , Li Hailin 
Published: April 2024

Abstract

Diabetic retinopathy, a leading cause of blindness in diabetic patients, necessitates precise lesion segmentation for effective grading. To address the challenges of low pixel occupancy and capturing multi-scale features in fundus images, we introduce a novel deep learning method: the Multi-Scale Spatial Attention Gate (MSAG) mechanism network. The model inputs images of various scales to extract diverse semantic information. Our innovative Spatial Attention Gate merges low-level spatial details with high-level semantic content, assigning hierarchical attention weights for accurate segmentation. Using the Modified Spatial Attention Gate in the inference stage enhances precision by combining prediction scales hierarchically, thus improving segmentation accuracy without increasing training costs. Testing on the IDRiD-S Dataset demonstrates that our fusion method surpasses others, with our model achieving balanced accuracy across all lesion types. Notably, our approach shows a 1\%-3\% higher accuracy for microaneurysms and overall accuracy compared to similar models, marking a significant advancement in diabetic retinopathy lesion segmentation.
Detrimental Role of Selected Soil Properties on Sedimentation of Dam- Reservoir
Authors: Lemma Tesfaye Mebrate , Moges Admasu 
Published: April 2024

Abstract

Reservoirs are broadly affected by sedimentation resulting from
soil erosion. This study aimed to analyze the detrimental role of
selected soil physical properties on the sedimentation of
reservoirs, in this case, Washa Dam-Reservoir, Ethiopia; in a view
to help the monitoring system. The catchment was divided into
square grids of size 300 m by 300 m as a study unit to collect all
information for the analysis. Thirty-two years of rainfall data
were used to analyze rainfall trends, and estimate runoff through
the runoff curve number model. Soil loss was estimated using USLE.
the study revealed that the soil is dominated by as high as 49%
clay content; pH of 4.6–5.6; and bulk density of 1.4 to 1.6
kg/m3 which is a challenge to plant growth affecting
ground cover in turn soil erosion. The average daily runoff was
13.55mm with a runoff coefficient of 26%. The average annual soil
loss was 6.9t ha− 1 y− 1 producing a yearly
volume of sediment 4918.32 tons. The catchment sediment delivery
ratio was 26.98% resulting in the maximum sediment of 1.81 t
ha− 1 with a total of 1327.95 tonsediment yield per year
forming 8mm thick sediment on average. In conclusion, although the
catchment has erosive rainfall and is relatively less conserved, it
revealed tolerable soil loss and sediment yield. Except using their
separate interrelation, soil properties, and erosion do not show
statistical correlation. Therefore, it is recommended to plan
interventions by giving priority to grids having sediment-promoting
soil factors coupled with paying attention to getting a working
relationship between soil properties and sedimentation for a better
monitoring system.
When does spillover indicate benefits to fish abundance and catch?
Authors: Hilborn Ray , Fitchett Mark , Hampton John , Ovando Daniel 
Published: April 2024

Abstract

Spillover is a term commonly applied to the movement of fish from inside a closed area to areas open to fishing outside of the closure and is usually identified by gradients in abundance or catch rates near the boundaries. It is commonly assumed that such gradients indicate that the closed area has benefitted the fishery and the total abundance of fish. We explore this assumption for spatially explicit models of closed areas with different intensities of fishing and fish movement and find that such gradients will be expected any time there is higher abundance inside the closed area. However, under most conditions it does not indicate a benefit to the fishery either in terms of total catch of catch rate, and unless fishing is intense total abundance is not expected to rise significantly. We examine one specific case of estimates spillover from the Papahānaumokuākea marine monument, one the largest no-take areas in the world, and see no evidence of spillover for yellowfin tuna and very slight evidence for bigeye tuna. These results are consistent with the theoretical models, the biology of the species and the intensity of fishing.
The Influence of tidal distortion on extreme water levels in Casamance estuary, Senegal.
Authors: Diouf Amadou , Sakho Issa , Sow Bamol Ali , Deloffre Julien , Diouf Mouhamadoul Bachir , Lafite Robert 
Published: April 2024

Abstract

The Casamance estuary in Senegal is experiencing hypersalination and silting, which are negatively impacting its mangrove ecosystem and maritime navigation. This is a critical issue for both biodiversity preservation and economic development. However, research and documentation on this estuary, particularly with regard to tides, have been relatively neglected. The focus of this study is on the impact of tidal asymmetry on extreme water levels in the region. Tide data was collected at the river entrance and at Ziguinchor, and analysed using digital tools such as Tide Peaks Toolbox and UTide. The results indicate that the average tidal range at Ziguinchor varies from 33 cm to 65 cm, with peaks in February and March and troughs in January and March. The duration of the ebb tide varies, with a duration of over 4 hours during spring tides and 2 hours during neap tides. During the dry season, the duration is extended to 3 hours and 30 minutes, leading to a greater accumulation of water upstream of the estuary, particularly in July. Maximum velocities of up to 30 cm/s are observed at the start of high tide, mainly in February. Harmonic analysis conducted over a six-month period indicates a reduction in amplitude of over 45% for semi-diurnal and diurnal waves. Additionally, there is a significant amplification of the upper diurnal waves, with a more asymmetry upstream of the estuary. Additionally, the analysis of residual water levels and currents emphasizes the complexity of tidal dynamics, particularly due to non-tidal influences. This study constitutes a good contribution to the understanding of the hydrodynamic functioning of estuarine systems in West Africa marked by a strong climatic contrast.
Microplastics in sea ice drifted to the Shiretoko Peninsula, the southern end of the Sea of Okhotsk
Authors: Ohno Hiroshi , Iizuka Yoshinori 
Published: April 2024

Abstract

Sea ice is regarded as a temporal sink and carrier of microplastics (MPs). Nevertheless, knowledge and understanding of MPs in sea ice remain sparse. This study investigated the abundance, composition, size (>30 micro m), and shape of MPs in four sea-ice cores retrieved at the southern end of the Sea of Okhotsk. Nine microplastic (MP) types, mostly with fragmentary shapes, were detected among ice-core sections. Most fragmentary MPs were smaller than 120 micro m, but all fiber MPs were in the largest size class (>210 micro m). MP concentrations were 0–60 particles/L, with an average of 21 particles/L. Higher occurrences of MPs observed in the lower ice layers are attributable to heavier MP contamination in the southern part of the sea and/or relocation of MPs in the ice matrix. No significant correlation was found between the distributions of MP and inorganic particle (sediment) abundances, implying difference in their kinetics of suspension freezing. Taken together, these findings suggest important implications for elucidating the nature and distribution of MPs in sea ice.
Analysis of heart rate variability in post-COVID-19 population
Authors: Qin Minyu , Lee Kwan , Yoo Seok-Ju 
Published: April 2024

Abstract

Symptoms caused by SARS-CoV-2 infection usually last 5-7 days; however, people experiencing symptoms for more than 5-7 days were reported, in a phase called long-term COVID-19 or post-COVID-19. Due to the ease of disease transmission and viral susceptibility, mild or asymptomatic infections are prevalent among young individuals; however, few studies have focused on the differences in autonomic functions in LC patients versus those recovering from COVID-19. In this study, we collected heart rate variability indices from patients survived for more than two months after a negative secondary RT-PCR test. A total of 173 individuals were included through autonomic balance surveys and questionnaires, including 57 controls with no history of COVID-19 and 84 COVID-19 survivors in COVID-19 rehabilitation group and 32 LC patients in LC group. The results suggested that the reduction in the very low frequency domain was significant among groups, and that in those aged <25 years, more individuals showed abnormal autonomic neuroactivity in the LC group compared to the COVID-19 rehabilitation group. The different results suggest that autonomic dysfunction still exists in those who have experienced the long-covid phase, which could be caused by sympathetic activation and inhibition of vagal activity.
Preparation of epoxy-functionalized AES (GAES) resins by high-temperature bulk polymerization
Authors: Sun Liting , Li Mingdong , Nie Bing , Ma Jianying , Cao Chunlei 
Published: April 2024

Abstract

In this paper, the monomers of styrene (St), acrylonitrile (AN), and glycidyl methacrylate (GMA) were grafted onto ethylene-propylene-diene-monomer (EPDM) rubbers, and the epoxy-functionalized AES (GAES) resins were successfully prepared by high-temperature bulk polymerization. The effects of polymerization reaction conditions, i.e. the content of initiator and chain transfer agent, the content of EPDM and GMA on the grafting rate, composition of free copolymers, molecular weights and their distributions of GAES resins were investigated in detail. The influence of GMA content on the thermal stabilities of GAES resins were also discussed. Experimental results showed that under the optimized experimental conditions, the highest grafting rate of GAES resins reached to 48.8% and the grafting efficiency was 35.3%. Under the same reaction conditions, the molecular weights of free copolymers can reach to 70,000 g mol− 1. The content of initiator and chain transfer agent had no obvious influence on the composition of free copolymers, but the component of GMA in free copolymers increased gradually with increasing content of EPDM. TG analysis results indicated that the incorporation of GMA decreased the thermal stabilities of GAES resins.
Detection of human drowsiness by the vestibulo-ocular reflex compensating for heartbeat-induced head perturbations
Authors: Yamanaka Toshimi , Hirata Yutaka 
Published: April 2024

Abstract

The vestibulo-ocular reflex (VOR) stabilizes vision during head movements by counter-rotating the eyes in the orbits. Although considered one of the simplest reflexes due to its minimal neuronal circuity comprising a 3-neuron arc, previous studies have shown that VOR performance deteriorates in both monkeys and humans when they are drowsy. Given constant head perturbations under dynamic environments, the VOR has been proposed as a viable biomarker for detecting human drowsiness in automobiles and other moving vehicles. Nevertheless, under stationary environments where exogenous head movements are absent, its applicability has been questioned. In this study, we demonstrate that each heartbeat generates small yet distinctive head movements, and the VOR compensates for these minor head perturbations. Furthermore, we show that the effectiveness of VOR responses varies with the degree of drowsiness, indicating that the VOR can serve as an indicator of drowsiness, even in stationary contexts such as in classrooms and offices.
Effects of Consumption of Probiotic Yogurt on Salivary Streptococcus mutans, IL-1β and TNF-α Levels in Adults with Initial Stages of Dental Caries: a Randomized, Double‑Blind, Placebo‑Controlled Clinical Trial
Authors: Javid Ahmad Zare , Amerian Essam , Basir Leila , Ekrami Alireza , Haghighizadeh Mohammad Hosein , Maghsoumi-Norouzabad Leila 
Published: April 2024

Abstract
Background
Dental caries is one of the most common human diseases. The aim of the present study was to determine the effect of consumption of probiotic yogurt containing Bifidobacterium lactis Bb12 on salivary Streptococcus mutans (S. mutans), interleukin-1β (IL-1β) and tumor necrosis factor alpha (TNF-α) levels in adults with initial stages of dental caries.
Methods and Material:
Sixty six 18–30 years old students with initial stages of dental caries were selected for this 2 weeks double blind randomized placebo controlled clinical trial and were randomly assigned into two groups: intervention (300g/d probiotic yogurt), and control (300 g/d conventional yogurt) groups. Unstimulated fasting saliva sample (2–3 ml) was collected pre and post-intervention for S. mutans bacteria counting and measurement of IL-1β and TNF-α cytokines levels. All Data were analyzed using SPSS.
Results
Salivary S. mutans and IL-1β changes were statistically signifcant in intervention group compared to their baseline and compared to the control group post intervention.
Conclusion
Consumption of probiotic yogurt containing B. lactis Bb12 may be beneficial for preventing of the progression of dental caries.
Trial registration:
This study was registered in Iran clinical trials: IRCT2014062518240N1.