65 research outputs found
Needle δ13C and mobile carbohydrates in Pinus koraiensis in relation to decreased temperature and increased moisture along an elevational gradient in NE China
A tree's crown interacts with atmospheric variables such as CO2, temperature, and humidity. Physioecology of leaves/needles (e.g. δ13C, mobile carbohydrates, and nitrogen) is, therefore, strongly affected by microclimate in and surrounding a tree crown. To understand the physiological responses of leaves to changes in air temperature and moisture, we measured δ13C, soluble sugars, starch, and total nitrogen (N) concentrations in current year and 1-yr-old needles of Pinus koraiensis trees, and compared the growing season air temperature and relative humidity within and outside P. koraiensis crowns along an elevational gradient from 760 to 1,420ma.s.l. on Changbai Mountain, NE China. Our results indicated that needle N and mobile carbohydrates concentrations, as well as needle δ13C values changed continuously with increasing elevation, corresponding to a continuous decrease in air temperature and an increase in relative humidity. Needle carbon and nitrogen status is highly significantly negatively correlated with temperature, but positively correlated with relative humidity. These results indicate that increases in air temperature in combination with decreases in relative humidity may result in lower levels of N and mobile carbohydrates in P. koraiensis trees, suggesting that future climate changes such as global warming and changes in precipitation patterns will directly influence the N and carbon physiology at P. koraiensis individual level, and indirectly affect the competitive ability, species composition, productivity and functioning at the stand and ecosystem level in NE China. Due to the relatively limited range of the transect (760-1,420m) studied, further research is needed to explain whether the present results are applicable to scales across large elevational gradient
TRIM29 acts as a potential senescence suppressor with epigenetic activation in nasopharyngeal carcinoma.
Epigenetic alterations marked by DNA methylation are frequent events during the early development of nasopharyngeal carcinoma (NPC). We identified that TRIM29 is hypomethylated and overexpressed in NPC cell lines and tissues. TRIM29 silencing not only limited the growth of NPC cells in vitro and in vivo, but also induced cellular senescence, along with reactive oxygen species (ROS) accumulation. Mechanistically, we found that TRIM29 interacted with voltage-dependent anion-selective channel 1 (VDAC1) to activate mitophagy clearing up damaged mitochondria, which are the major source of ROS. In patients with NPC, high levels of TRIM29 expression are associated with an advanced clinical stage. Moreover, we detected hypomethylation of TRIM29 in patient nasopharyngeal swab DNA. Our findings indicate that TRIM29 depends on VDAC1 to induce mitophagy and prevents cellular senescence by decreasing ROS. Detection of aberrantly methylated TRIM29 in the nasopharyngeal swab DNA could be a promising strategy for the early detection of NPC
Effect of the categorization method on the diagnostic performance of ultrasound risk stratification systems for thyroid nodules
ObjectiveTo evaluate whether the categorization methods of risk stratification systems (RSSs) is a decisive factor that influenced the diagnostic performances and unnecessary FNA rates in order to choose optimal RSS for the management of thyroid nodules.MethodsFrom July 2013 to January 2019, 2667 patients with 3944 thyroid nodules had undergone pathological diagnosis after thyroidectomy and/or US-guided FNA. US categories were assigned according to the six RSSs. The diagnostic performances and unnecessary FNA rates were calculated and compared according to the US-based final assessment categories and the unified size thresholds for biopsy proposed by ACR-TIRADS, respectively.ResultsA total of 1781 (45.2%) thyroid nodules were diagnosed as malignant after thyroidectomy or biopsy. Significantly lowest specificity and accuracy, along with the highest unnecessary FNA rates were seen in EU-TIRADS for both US categories (47.9%, 70.2%, and 39.4%, respectively, all P < 0.05) and indications for FNA (54.2%, 50.0%, and 55.4%, respectively, all P < 0.05). Diagnostic performances for US-based final assessment categories exhibited similar accuracy for AI-TIRADS, Kwak-TIRADS, C-TIRADS, and ATA guidelines (78.0%, 77.8%, 77.9%, and 76.3%, respectively, all P > 0.05), while the lowest unnecessary FNA rate was seen in C-TIRADS (30.9%) and without significant differences to that of AI-TIRADS, Kwak-TIRADS, and ATA guideline (31.5%, 31.7%, and 33.6%, respectively, all P > 0.05). Diagnostic performance for US-FNA indications showed similar accuracy for ACR-TIRADS, Kwak-TIRADS, C-TIRADS and ATA guidelines (58.0%, 59.7%, 58.7%, and 57.1%, respectively, all P > 0.05). The highest accuracy and lowest unnecessary FNA rate were seen in AI-TIRADS (61.9%, 38.6%) and without significant differences to that of Kwak-TIRADS(59.7%, 42.9%) and C-TIRADS 58.7%, 43.9%, all P > 0.05).ConclusionThe different US categorization methods used by each RSS were not determinant influential factors in diagnostic performance and unnecessary FNA rate. For daily clinical practice, the score-based counting RSS was an optimal choice
Artificial intelligence breast ultrasound and handheld ultrasound in the BI-RADS categorization of breast lesions: A pilot head to head comparison study in screening program
BackgroundArtificial intelligence breast ultrasound diagnostic system (AIBUS) has been introduced as an alternative approach for handheld ultrasound (HHUS), while their results in BI-RADS categorization has not been compared.MethodsThis pilot study was based on a screening program conducted from May 2020 to October 2020 in southeast China. All the participants who received both HHUS and AIBUS were included in the study (N = 344). The ultrasound videos after AIBUS scanning were independently watched by a senior radiologist and a junior radiologist. Agreement rate and weighted Kappa value were used to compare their results in BI-RADS categorization with HHUS.ResultsThe detection rate of breast nodules by HHUS was 14.83%, while the detection rates were 34.01% for AIBUS videos watched by a senior radiologist and 35.76% when watched by a junior radiologist. After AIBUS scanning, the weighted Kappa value for BI-RADS categorization between videos watched by senior radiologists and HHUS was 0.497 (p < 0.001) with an agreement rate of 78.8%, indicating its potential use in breast cancer screening. However, the Kappa value of AIBUS videos watched by junior radiologist was 0.39, when comparing to HHUS.ConclusionAIBUS breast scan can obtain relatively clear images and detect more breast nodules. The results of AIBUS scanning watched by senior radiologists are moderately consistent with HHUS and might be used in screening practice, especially in primary health care with limited numbers of radiologists
RAGE Mediates a Novel Proinflammatory Axis A Central Cell Surface Receptor for S100/Calgranulin Polypeptides
AbstractS100/calgranulin polypeptides are present at sites of inflammation, likely released by inflammatory cells targeted to such loci by a range of environmental cues. We report here that receptor for AGE (RAGE) is a central cell surface receptor for EN-RAGE (e xtracellular n ewly identified RAGE-binding protein) and related members of the S100/calgranulin superfamily. Interaction of EN-RAGEs with cellular RAGE on endothelium, mononuclear phagocytes, and lymphocytes triggers cellular activation, with generation of key proinflammatory mediators. Blockade of EN-RAGE/RAGE quenches delayed-type hypersensitivity and inflammatory colitis in murine models by arresting activation of central signaling pathways and expression of inflammatory gene mediators. These data highlight a novel paradigm in inflammation and identify roles for EN-RAGEs and RAGE in chronic cellular activation and tissue injury
The Genomes of Oryza sativa: A History of Duplications
We report improved whole-genome shotgun sequences for the genomes of indica and japonica rice, both with multimegabase contiguity, or almost 1,000-fold improvement over the drafts of 2002. Tested against a nonredundant collection of 19,079 full-length cDNAs, 97.7% of the genes are aligned, without fragmentation, to the mapped super-scaffolds of one or the other genome. We introduce a gene identification procedure for plants that does not rely on similarity to known genes to remove erroneous predictions resulting from transposable elements. Using the available EST data to adjust for residual errors in the predictions, the estimated gene count is at least 38,000–40,000. Only 2%–3% of the genes are unique to any one subspecies, comparable to the amount of sequence that might still be missing. Despite this lack of variation in gene content, there is enormous variation in the intergenic regions. At least a quarter of the two sequences could not be aligned, and where they could be aligned, single nucleotide polymorphism (SNP) rates varied from as little as 3.0 SNP/kb in the coding regions to 27.6 SNP/kb in the transposable elements. A more inclusive new approach for analyzing duplication history is introduced here. It reveals an ancient whole-genome duplication, a recent segmental duplication on Chromosomes 11 and 12, and massive ongoing individual gene duplications. We find 18 distinct pairs of duplicated segments that cover 65.7% of the genome; 17 of these pairs date back to a common time before the divergence of the grasses. More important, ongoing individual gene duplications provide a never-ending source of raw material for gene genesis and are major contributors to the differences between members of the grass family
2-Amino-5-methylpyridinium nitrate
In the title salt, C6H9N2+&#183;NO3&#8722;, the 2-amino-5-methylpyridinium cation and the nitrate anion are cyclically linked through pyridinium and amine N&#8212;H...O hydrogen bonds [graph set R43(12)]. These units are extended into a zigzag chain structure lying parallel to the a axis, through a second cyclic R22(8) association involving amine N&#8212;H...O and aromatic C&#8212;H...O hydrogen bonds to nitrate O-atom acceptors
Study of Internal Drainage Systems for Steel Bridge Deck Pavements
As large span steel bridges develop rapidly, the type of steel deck paving is also diversifying. However, the current steel deck paving layer is a dense-graded mixture of both upper and lower layers. This makes it difficult for water to drain out of the dense deck when it enters the interior of the deck, and the deck is easily damaged by the traffic load. This paper aims to prolong the service life of the pavement and solve the problem that the pavement is prone to water damage under the existing pavement system. In this paper, a new steel bridge deck paving system is formed by developing a new type of waterproofing binder layer material and developing an open-graded paving layer underlayment. Through indoor tests and finite element software analysis, the effect of the environment on the pull-out strength of the waterproofing binder layer material under different permaculture conditions is investigated; a suitable void ratio control range for the paving layer is explored through paving layer seepage analysis and indoor tests. The study revealed that the new epoxy resin waterproofing bonding layer was able to maintain a large pull-out strength value in a 60 °C water bath for 2 weeks. The paving with void ratios of 18, 20, and 22% were all able to drain 50% of the water inside the paving within 2 h, with excellent drainage capacity. Based on the modeling analysis and indoor test results, the target void ratio of the asphalt mix under the pavement is recommended to be controlled at 20–22%, with a void ratio in this range to solve the problem of water entering the steel bridge deck pavement and causing pavement distress
Study of Internal Drainage Systems for Steel Bridge Deck Pavements
As large span steel bridges develop rapidly, the type of steel deck paving is also diversifying. However, the current steel deck paving layer is a dense-graded mixture of both upper and lower layers. This makes it difficult for water to drain out of the dense deck when it enters the interior of the deck, and the deck is easily damaged by the traffic load. This paper aims to prolong the service life of the pavement and solve the problem that the pavement is prone to water damage under the existing pavement system. In this paper, a new steel bridge deck paving system is formed by developing a new type of waterproofing binder layer material and developing an open-graded paving layer underlayment. Through indoor tests and finite element software analysis, the effect of the environment on the pull-out strength of the waterproofing binder layer material under different permaculture conditions is investigated; a suitable void ratio control range for the paving layer is explored through paving layer seepage analysis and indoor tests. The study revealed that the new epoxy resin waterproofing bonding layer was able to maintain a large pull-out strength value in a 60 °C water bath for 2 weeks. The paving with void ratios of 18, 20, and 22% were all able to drain 50% of the water inside the paving within 2 h, with excellent drainage capacity. Based on the modeling analysis and indoor test results, the target void ratio of the asphalt mix under the pavement is recommended to be controlled at 20–22%, with a void ratio in this range to solve the problem of water entering the steel bridge deck pavement and causing pavement distress
Study on Fire Smoke Distribution and Safety Evacuation of Subway Station Based on BIM
A subway station is a confined space, so it is very important to evacuate people safely in case of a fire. It is necessary to study and analyze the smoke distribution and evacuation ability of different station layout schemes when fire occurs. Taking a subway station as an example, this paper combines BIM (Building Information Model) technology with the fire safety evacuation of the subway station. First, we optimize the layout of the public area of the subway station and use BIM technology to establish a subway station model. Then, we use the PyroSim software to establish a subway station fire model to analyze fire development in different locations of the station in the optimization scheme, and determine the time it takes for CO concentration, smoke temperature and visibility to reach the critical value of danger. Finally, a subway station fire evacuation model is established using the Pathfinder software to study the safety evacuation of people in the subway station fire. The results show that it takes the shortest time for the visibility in the station to reach the critical value under fire conditions, and the threat to safety evacuation is the greatest. The available safe evacuation time of the optimized subway station is greater than the required safe evacuation time under different fire conditions, that is, the optimized subway station arrangement can ensure the safety evacuation of the personnel in the subway station under fire conditions. The research results can serve as reference for the optimization of safety evacuation designs of similar subway stations
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