RESUMO
The high-throughput and full-time acquisition of images of crop growth processes, and the analysis of the morphological parameters of their features, is the foundation for achieving fast breeding technology, thereby accelerating the exploration of germplasm resources and variety selection by crop breeders. The evolution of embryonic soybean radicle characteristics during germination is an important indicator of soybean seed vitality, which directly affects the subsequent growth process and yield of soybeans. In order to address the time-consuming and labor-intensive manual measurement of embryonic radicle characteristics, as well as the issue of large errors, this paper utilizes continuous time-series crop growth vitality monitoring system to collect full-time sequence images of soybean germination. By introducing the attention mechanism SegNext_Attention, improving the Segment module, and adding the CAL module, a YOLOv8-segANDcal model for the segmentation and extraction of soybean embryonic radicle features and radicle length calculation was constructed. Compared to the YOLOv8-seg model, the model respectively improved the detection and segmentation of embryonic radicles by 2% and 1% in mAP50-95, and calculated the contour features and radicle length of the embryonic radicles, obtaining the morphological evolution of the embryonic radicle contour features over germination time. This model provides a rapid and accurate method for crop breeders and agronomists to select crop varieties.
RESUMO
Fetal development is essential to the human lifespan. As more and more multifetal gestations have been reported recently, clinical diagnosis using magnetic resonance imaging (MRI), which introduced radiofrequency (RF) exposure, raised public concerns. The present study developed two whole-body pregnant models of 31 and 32 gestational weeks (GWs) with twin fetuses and explored RF exposure by 1.5 and 3.0 T MRI. Differences in the relative position of the fetus and changes in fetal weight can cause differences in fetal peak local specific absorption rate averaged over 10 g tissue (pSAR10g). Variation of pSAR10g due to different fetal positions can be ~35%. Numerically, twin and singleton fetal pSAR10g results were not significantly different, however twin results exceeded the limit in some cases (e.g. fetuses of 31 GW at 1.5 T), which indicated the necessity for further research employing anatomically correct twin-fetal models coming from various GWs and particular sequence to be applied.
Assuntos
Feto , Imageamento por Ressonância Magnética , Ondas de Rádio , Humanos , Gravidez , Feminino , Imageamento por Ressonância Magnética/métodos , Feto/efeitos da radiação , Feto/diagnóstico por imagem , Gêmeos , Idade Gestacional , Desenvolvimento Fetal/efeitos da radiaçãoRESUMO
Chemical modifications of proteins induced by ambient ozone (O3) and nitrogen oxides (NOx) are of public health concerns due to their potential to trigger respiratory diseases. The laboratory and environmental exposure systems have been widely used to investigate their relevant mechanism in the atmosphere. Using bovine serum albumin (BSA) as a model protein, we evaluated the two systems and aimed to reduce the uncertainties of both the reactants and products in the corresponding kinetic study. In the laboratory simulation system, the generated gaseous pollutants showed negligible losses. Ten layers of BSA were coated on the flow tube with protein extraction recovery of 87.4%. For environmental exposure experiment, quartz fiber filter was selected as the upper filter with low gaseous O3 (8.0%) and NO2 (1.7%) losses, and cellulose acetate filter was appropriate for the lower filter with protein extraction efficiency of 95.2%. The protein degradation process was observed without the exposure to atmospheric oxidants and contributed to the loss of protein monomer mass fractions, while environmental factors (e.g., molecular oxygen and ultraviolet) may cause greater protein monomer losses. Based on the evaluation, the study exemplarily applied the two systems to protein modification and both showed that O3 promotes the protein oligomerization and nitration, while increased temperature can accelerate the oligomerization and increased relative humidity can inhibit the nitration in the environmental exposure samples. The developed laboratory and environmental systems are suitable for studying protein modifications formed under different atmospheric conditions. A combination of the two will further reveal the actual mechanism of protein modifications.
Assuntos
Poluentes Atmosféricos , Ozônio , Ozônio/química , Poluentes Atmosféricos/análise , Soroalbumina Bovina/química , Exposição Ambiental , Óxidos de Nitrogênio/análise , Proteínas/químicaRESUMO
Organophosphate esters (OPEs) are a class of emerging and ubiquitous contaminants that are attracting increasing attention, and their large-scale use as flame retardants and plasticizers has led to their pervasive presence in the environment, although their broader impacts remain unknown. In this study, 11 OPEs were measured in the atmosphere of Southeast Asia and Southwest China during 2016. The ∑11OPEs were higher in this region (78.0-1670 pg/m3, mean 458 pg/m3) than in many remote areas, lower than in developed regions, and comparable to levels in many developing country cities. Generally, the ∑11OPEs were higher in urban (105-1670 pg/m3, mean 538 pg/m3) than in suburban (78.0-1350 pg/m3, mean 388 pg/m3). Seasonal variations of OPEs in the air were more pronounced in Cambodia and Laos, especially for Triphenyl Phosphate (TPHP). Seasonal variations of ∑11OPEs in most regions correspond to changes in temperature and rainfall. Biomass burning may be also a factor in facilitating OPE emissions from biomass materials or soil into the atmosphere of Southeast Asia. The random forest analysis showed that among these, rainfall had the greatest effect on the seasonal variation of atmospheric OPE concentrations, followed by biomass burning and temperature. The inter-regional variation of ∑11OPEs in Southeast Asia was related to population and economic development in each region. Airflow trajectories indicated that the OPEs in this region were mainly from local sources. The health risk assessment revealed that the inhalation exposure risks of OPEs to the residents in the study areas were very low during the sampling period, but may be increasing.
Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Ésteres , Organofosfatos , China , Poluentes Atmosféricos/análise , Organofosfatos/análise , Ésteres/análise , Retardadores de Chama/análise , Estações do Ano , Índia , Atmosfera/química , Poluição do Ar/estatística & dados numéricosRESUMO
The L1 cell adhesion molecule (L1) has demonstrated a range of beneficial effects in animal models of spinal cord injury, neurodegenerative disease, and ischemia; however, the role of L1 in TBI has not been fully examined. Mutations in the L1 gene affecting the extracellular domain of this type 1 transmembrane glycoprotein have been identified in patients with L1 syndrome. These patients suffer from hydrocephalus, MASA (mental retardation, adducted thumbs, shuffling gait, aphasia) symptoms, and corpus callosum agenesis. Clinicians have observed that recovery post-traumatic brain injury (TBI) varies among the population. This variability may be explained by the genetic differences present in the general population. In this study, we utilized a novel mouse model of L1 syndrome with a mutation at aspartic acid position 201 in the extracellular domain of L1 (L1-201). We assessed the impact of this specific single nucleotide polymorphism (SNP) localized to the X-chromosome L1 gene on recovery outcomes following TBI by comparing the L1-201 mouse mutants with their wild-type littermates. We demonstrate that male L1-201 mice exhibit significantly worse learning and memory outcomes in the Morris water maze after lateral fluid percussion (LFP) injury compared to male wild-type mice and a trend to worse motor function on the rotarod. However, no significant changes were observed in markers for inflammatory responses or apoptosis after TBI.
Assuntos
Lesões Encefálicas Traumáticas , Doenças Genéticas Ligadas ao Cromossomo X , Hidrocefalia , Deficiência Intelectual , Molécula L1 de Adesão de Célula Nervosa , Doenças Neurodegenerativas , Paraplegia Espástica Hereditária , Humanos , Masculino , Animais , Camundongos , Molécula L1 de Adesão de Célula Nervosa/genética , Polimorfismo de Nucleotídeo Único , Hidrocefalia/genéticaRESUMO
Here we unveil a chiral molecular redox switch derived from PDI-based twistacenesâchPDI[2] that has the remarkable attributes of high-intensity and a broadband chiral response. This material exhibits facile, stable, and reversible multistate chiroptical switching behavior over a broad active wavelength range close to 700 nm, encompassing ultraviolet, visible, and near-infrared regions. Upon reduction, chPDI[2] exhibits a substantial increase in the amplitude of its circular dichroic response, with an outstanding |ΔΔε| > 300 M-1 cm-1 and a high dissymmetry factor of 3 × 10-2 at 960 nm. DFT calculations suggest that the long wavelength CD signal for doubly reduced chPDI[2] originates from excitation of the PDI backbone to the π* orbital of the bridging alkene. Importantly, the dimer's molecular contortion facilitates ionic diffusion, enabling chiral switching in solid state films. The high dissymmetry factors and near-infrared response establish chPDI[2] as a unique chiroptic switch.