Outcomes in pediatric extracorporeal cardiopulmonary resuscitation: A single-center retrospective study from 2007 to 2022 in China.

OBJECTIVE: We aimed to investigate the prognostic factors of pediatric extracorporeal cardiopulmonary resuscitation (ECPR). METHODS: The retrospective study included a total of 77 pediatric cases (7 neonates and 70 children) who underwent ECPR after in-hospital and out-of-hospital cardiac arrest between July 2007 and December 2022. Primary endpoints were complications, while secondary endpoints included all-cause in-hospital mortality. RESULTS: Among the 45 cases experiencing complications, 4 neonates and 41 children had multiple simultaneous complications, primarily neurological issues in 25 cases. Additionally, organ failure occurred in 11 cases, and immunodeficiency was present in two cases. Furthermore, 9 cases experienced bleeding events, and 13 cases showed thrombosis. Patients with complications had lower weight, shorter ECMO durations, and longer CPR durations. Non-survivors had longer CPR durations and shorter durations of ECMO, ICU stay, and mechanical ventilation compared to survivors. Complications were more prevalent in non-survivors, particularly organ failure and bleeding events. CONCLUSION: Weight, CPR duration, and ECMO duration were associated with complications, suggesting areas for treatment optimization. The higher occurrence of complications in non-survivors underscores the importance of early detection and management to improve survival rates. Our findings suggest clinicians consider these factors in prognostic assessments to enhance the effectiveness of ECPR programs.

Testing of two SNP array-based genealogy algorithms using extended Han Chinese pedigrees and recommendations for improved performances in forensic practice.

Distant genetic relatives can be linked to a crime scene sample by computing identity-by-state (IBS) and identity-by-descent (IBD) shared by individuals. To test the methods of genetic genealogy estimation and optimal the parameters for forensic investigation, a family-based genetic genealogy analysis was performed using a dataset of 262 Han Chinese individuals from 11 families. The dataset covered relative pairs from 1st- to 14th degrees. But the 7th-degree relative is the most distant kinship to be fully investigated, and each individual has ∼200 relatives within the 7th degree. The KING algorithm by calculating IBS and IBD statistics can correctly discriminate the first-degree relationships of monozygotic twin, parent-offspring and full sibling. The inferred relationship was reliable within the fifth-degree, false positive rate <1.8%. The IBD segment algorithm, GERMLINE + ERSA, could provide reliable inference result prolonged to eighth degree. Analysis of IBD segments produced obviously false negative estimations (<27.4%) rather than false positives (0%) within the eighth-degree inferences. We studied different minimum IBD segment threshold settings (changed from >0 to 6 cM); the inferred results did not make much difference. In distant relative analysis, genetically undetectable relationships begin to occur from the sixth degree (second cousin once removed), which means the offspring after seven meiotic divisions may share no ancestor IBD segment at all. Application of KING and GERMLINE + ERSA worked complementarily to ensure accurate inference from first degree to eighth degree. Using simulated low call rate data, the KING algorithm shows better tolerance to marker decrease compared with the GERMLINE + ERSA segment algorithm.

Distinct origins and functions of cardiac orthotopic macrophages.

Macrophages are one cell type in the innate immune system. Recent studies involving macrophages have overturned the conventional concept that circulating bone marrow-derived blood mononuclear cells in the adult body continuously replace macrophages residing in the tissues. Investigations using refined technologies have suggested that embryonic hematopoiesis can result in the differentiation into macrophage subgroups in some tissues. In adulthood, these macrophages are self-sustaining via in situ proliferation, with little contribution of circulating bone marrow-derived blood mononuclear cells. Macrophages are integral component of the heart, accounting for 8% of the non-cardiac cells. The use of innovative molecular techniques in paradigm shifting researches has revealed the complexity of cardiac macrophages, including their heterogeneity and ontological diversity. Resident cardiac macrophages modulate the physiological and pathophysiological processes of the cardiovascular system, with distinct and crucial roles in healthy and injured hearts. Their functions include sensing of pathogens, antigen presentation, digesting cell debris, regulating inflammatory responses, generating distinct cytokines, and secreting some regulatory factors. More recent studies have revealed further functions of cardiac macrophages. This review focuses on macrophages within the cardiovascular system. We discuss evidence that has changed our collective view of cardiac macrophage subgroups, and improved our understanding of the different phenotypes, cell surface markers, heterogeneities, origins, developments, and the dynamic and separate roles of these cardiac macrophage subgroups in the steady state and injured hearts. This review may provide novel insights concerning the pathophysiology of cardiac-resident macrophages in cardiovascular diseases and innovative therapeutic strategies that could include the modulation of the role of macrophages in cardiovascular injuries.

[Human facial shape related SNP analysis in Han Chinese populations].

Human facial morphology is one of the important visible biological characteristics. Understanding the genetic basis underlying facial shape traits has important implications in population genetics, developmental biology, and forensic science. This study extracted 136 Euclidean distance phenotypes from 17 facial features of high-resolution 3D facial images in 1177 Chinese Han adult males. Based on 3× low-depth sequencing data, linear regression was used to analyze the correlation between 125 reported SNPs significantly associated with facial morphology and 136 facial phenotypes. As a result, a total of twelve SNPs from ten genes demonstrated significant association with one or more facial shape traits after adjusting for multiple testing (significance threshold P < 1.35 × 10 -3 ), together explaining up to 3.89% of age-, and BMI-adjusted facial phenotype variance. These included TEX41 rs17479393, PAX3 rs974448, RAB7A/ACAD9 rs2977562, DCHS2 rs9995821, DCHS2 rs2045323, C5orf50 rs6555969, SUPT3H/RUNX2 rs1852985, MSRA rs11782517, EYA1 rs10504499, GSC rs2224309, DICER1 rs7161418 and DHX35 rs2206437.These results revealed the genetics basis of facial morphology of Han Chinese population, and provided reference data for DNA-based face prediction.

The ancestry inference of Chinese populations using 74-plex SNPs system.

A panel of ancestry informative SNPs (AISNPs) can be used to analyze the genetic components of a population and infer the ancestral origin of a DNA sample. Previously, we have selected a 74-AISNPs panel and used it to infer the ancestry of unknown individuals in the following ten geographical regions: Sub-Saharan Africa, North Africa, Europe, Pacific, Americas, Southwest Asia, South Asia, North Asia, East Asia and Southeast Asia. We have also established a 74-plex SNPs assay based on SEQUENOM system. In the present study, we genotyped 1371 individuals from 14 populations of China using this multiplex assay, and validated its ability to infer the ancestry in Chinese populations. Firstly, based on the reference database of 3628 individuals from 57 world populations, Structure and Heatmap were employed to evaluate the population differentiation capacity. The training data include 1654 individuals from 14 Chinese populations and 3 populations from 1K Genome, which are not included in the reference database. Then the likelihood ratio and ancestry components were analyzed for individual ancestry assignment using the 74-plex SNPs. The minimum amount of DNA required for a full genotype of the 74 SNPs is 1.5 ng, which is applicable for forensic analysis. The results demonstrate that this system can be used in differentiating the population from ten geographical regions. The ancestry inference accuracy for EUR/SAFR/AME population is 95.4%, 71.0% for East Asia and 66.4% for Southeast Asia respectively. The ancestry inference inclusive rate for EUR/SAFR/AME population is 1.06%, 17.9% for East Asia and 33.3% for Southeast Asia respectively. The results suggest that this method can be used in forensic investigations of criminal cases.

Diagnostic roles of urinary kidney injury molecule 1 and soluble C5b-9 in acute tubulointerstitial nephritis.

Acute tubulointerstitial nephritis (ATIN) is a common cause of acute kidney injury characterized by inflammatory cells infiltrating in the interstitium. The present study aimed to explore noninvasive biomarkers that might indicate activity of pathological injuries and help direct treatment. Fifty-four patients with clinical-pathologically diagnosed ATIN from January 1, 2014, to June 30, 2016, at Peking University First Hospital were enrolled. Urine samples were collected on the morning of renal biopsy and assessed for urinary kidney injury molecule-1 (KIM-1) and urinary soluble C5b-9 (sC5b-9). Immunofluorescence staining for KIM-1 and C5b-9 was performed in biopsied kidney sections from ATIN cases. The clinical and pathological relevance of the two urinary biomarkers was analyzed. Both urinary KIM-1 and sC5b-9 values were significantly elevated in patients with ATIN compared with healthy controls. The urinary KIM-1 level positively correlated with urinary N-acetyl-ß-d-glucosaminidase (r = 0. 542, P = 0.001) and the pathological tubular injury score (r = 0.469, P < 0.001), whereas the urinary sC5b-9 level was related to pathological activity scores for tubular injury (r = 0.413, P = 0.002), interstitial inflammation (r = 0.388, P = 0.004), and treatment response (r = 0.564, P < 0.001). Urinary KIM-1 tended to have better diagnostic value for tubular injury than urinary sC5b-9, whereas only urinary sC5b-9 was able to demonstrate severe interstitial inflammation. A combination of urinary KIM-1 and sC5b-9 had an area under the receiver-operating characteristic curve of 0.864 (95% confidence interval: 0.766-0.963, P < 0.001, sensitivity: 75%, specificity: 88%) for acute tissue injury in ATIN. KIM-1 expression was markedly increased in renal tubular cells in both ATIN and acute tubular necrosis conditions, whereas a significant upregulation of C5b-9 was only detected in the tubular cells and interstitial cells in ATIN cases. Urinary KIM-1 is a specific biomarker for renal tubular injury in ATIN, whereas urinary sC5b-9 is valuable in demonstrating severe interstitial inflammation. The combination of these two biomarkers helps identify patients at an acute injury stage and, therefore, might facilitate clinical evaluation and guide immunosuppressive therapy.

Molecular Phylogeny and Dating Reveal a Terrestrial Origin in the Early Carboniferous for Ascaridoid Nematodes.

Ascaridoids are among the commonest groups of zooparasitic nematodes (roundworms) and occur in the alimentary canal of all major vertebrate groups, including humans. They have an extremely high diversity and are of major socio-economic importance. However, their evolutionary history remains poorly known. Herein, we performed a comprehensive phylogenetic analysis of the Ascaridoidea. Our results divided the Ascaridoidea into six monophyletic major clades, i.e., the Heterocheilidae, Acanthocheilidae, Anisakidae, Ascarididae, Toxocaridae, and Raphidascarididae, among which the Heterocheilidae, rather than the Acanthocheilidae, represents the sister clade to the remaining ascaridoids. The phylogeny was calibrated using an approach that involves time priors from fossils of the co-evolving hosts, and dates the common ancestor of the Ascaridoidea back to the Early Carboniferous (approximately 360.47-325.27 Ma). The divergence dates and ancestral host types indicated by our study suggest that members of the Ascaridoidea first parasitized terrestrial tetrapods, and subsequently, extended their host range to elasmobranchs and teleosts. We also propose that the fundamental terrestrial-aquatic switches of these nematodes were affected by changes in sea-level during the Triassic to the Early Cretaceous.

Aureonitols A and B, Two New C13 -Polyketides from Chaetomium globosum, an Endophytic Fungus in Salvia miltiorrhiza.

Two new C13 -polyketides, aureonitols A and B (1 and 2), along with five known compounds (3-7), were isolated from the solid fermentation culture of the plant endophytic fungus Chaetomium globosum from the aerial parts of Salvia miltiorrhiza. The structures and absolute configurations of 1 and 2 were determined by comprehensive spectroscopic data analysis and computed methods. Compound 5 was found to display the remarkable antimicrobial activities against four multidrug-resistant bacteria (Enterococcus faecalis, Enterococcus faecium, Staphylococcus aureus, and Staphylococcus epidermidis) with MIC values of 3.13-6.25 µg/mL (ciprofloxacin: 0.78-1.56 µg/mL), and also against all tested fungal strains with MIC values of 3.13-25 µg/mL (ketoconazole: 0.78-12.50 µg/mL).

[The effect of EDARV370A on facial and ear morphologies in Uyghur population].

The ectodysplasinA receptor gene (EDAR) plays an important role in the development of ectoderm. The derived G allele of its key missense variant EDARV370A is prevalent in East Asians and Americans, but rare in Africans and Europeans. This leads to distinct ectodermal-derived phenotypes between different continental groups, such as the straighter and thicker hair, more eccrine sweat glands, feminine smaller breasts, shovel incisors characteristic of East Asians. At present, we know little about the association between EDARV370A and facial and ear morphology characteristics. To better understand the effect of EDARV370A on craniofacial phenotypes, we systematically examined the association between EDARV370A and 136 facial quantitative phenotypes, one chin ordinal phenotype and six ear ordinal phenotypes in 715 Uyghurs. The quantitative phenotypes were derived by applying our automated landmark annotation method to facial 3D photos and the ordinal phenotypes were manually graded from facial 2D photos. The analysis identified significant association (P<0.05 after multiple testing correction) between EDARV370A and eight facial phenotypes, one chin phenotype and three ear morphology phenotypes. Our study thus elucidated the pleotropic effect of EDARV370A on craniofacial phenotypes in a European-Asian admixed Uyghur population.

A cadmium stress-responsive gene AtFC1 confers plant tolerance to cadmium toxicity.

BACKGROUND: Non-essential trance metal such as cadmium (Cd) is toxic to plants. Although some plants have developed elaborate strategies to deal with absorbed Cd through multiple pathways, the regulatory mechanisms behind the Cd tolerance are not fully understood. Ferrochelatase-1 (FC1, EC4.99.1.1) is the terminal enzyme of heme biosynthesis, catalyzing insertion of ferrous ion into protoporphyrin IX. Recent studies have shown that FC1 is involved in several physiological processes. However, its biological function associated with plant abiotic stress response is poorly understood. RESULTS: In this study, we showed that AtFC1 was transcriptionally activated by Cd exposure. AtFC1 overexpression (35S::FC1) lines accumulated more Cd and non-protein thiol compounds than wild-type, and conferred plant tolerance to Cd stress, with improved primary root elongation, biomass and chlorophyll (Chl) content, and low degree of oxidation associated with reduced H2O2, O·2- and peroxides. In contrast, the AtFC1 loss of functional mutant fc1 showed sensitivity to Cd stress. Exogenous provision of heme, the product of AtFC1, partially rescued the Cd-induced toxic phenotype of fc1 mutants by improving the growth of seedlings, generation of glutathione (GSH) and phytochelatins (PCs), and GSH/PCs-synthesized gene expression (e.g. GSH1, GSH2, PCS1, and PCS2). To investigate the mechanism leading to the AtFC1 regulating Cd stress response in Arabidopsis, a transcriptome of fc1 mutant plants under Cd stress was profiled. Our data showed that disfunction of AtFC1 led to 913 genes specifically up-regulated and 522 genes down-regulated in fc1 mutants exposed to Cd. Some of the genes are involved in metal transporters, Cd-induced oxidative stress response, and detoxification. CONCLUSION: These results indicate that AtFC1 would act as a positive regulator of plant tolerance to Cd stress. Our study will broaden our understanding of the role of FC1 in mediating plant response to Cd stress and provide a basis for further exploration of its downstream genes.

Optimization and validation of analysis method based on 27-plex SNP panel for ancestry inference.

Anthropology generally divides the individuals into the East Asian Mongolia race, European Caucasian race and African Nigro race. The 27-plex single nucleotide polymorphism (SNP) panel for ancestry information has been established to differentiate samples from East Asian, European, African and admixture populations of East Asian and European origin by genotyping and ancestry inference. To infer ancestry for unknown individuals, we established an optimized analysis pipeline based on the likelihood ratio, ancestry component and individual ancestry assignment. Four samples from East Asian, European, African and admixture populations of East Asian and European origin were tested using the optimized analysis pipeline. Cross validation within basic referential database and validation of 1 010 test samples were both used to evaluate the inference process. The results showed that accuracy of the method was higher than 99% in East Asia, Europe, Africa and admixture populations. The inference method can characterize the ancestry information of DNA donors, and has important practical application values in the field of human molecular and forensic genetics.

Morphological study of Ophidascaris excavata Hsü & Hoeppli, 1931 (Ascaridida: Ascarididae) from Gloydius brevicaudus (Stejneger) (Reptilia: Viperidae).

Ophidascaris excavata Hsü & Hoeppli, 1931 is a poorly known ascaridid parasite reported from the short-tailed pit viper Gloydius brevicaudus (Stejneger) (Reptilia: Viperidae) in China. In the present paper, the detailed morphology of this nematode was studied using light and scanning electron microscopy (SEM) based on newly collected material. The results revealed several important, but previously unreported, morphological features, including the presence of one pair of small, finger-like prolongations on each lip, narrow cervical alae beginning well posterior to the base of the ventrolateral lips and the second pair of postcloacal ventro-lateral papillae being double; in addition, there is no intestinal caecum. These supplementary morphological and morphometric data, especially the detailed morphological features obtained herein under SEM, would help us to understand the relationships of O. excavata with its congeners and enable us to diagnose this species more accurately.

The von Hippel-Lindau protein pVHL inhibits ribosome biogenesis and protein synthesis.

pVHL, the product of von Hippel-Lindau (VHL) tumor suppressor gene, functions as the substrate recognition component of an E3-ubiquitin ligase complex that targets hypoxia inducible factor α (HIF-α) for ubiquitination and degradation. Besides HIF-α, pVHL also interacts with other proteins and has multiple functions. Here, we report that pVHL inhibits ribosome biogenesis and protein synthesis. We find that pVHL associates with the 40S ribosomal protein S3 (RPS3) but does not target it for destruction. Rather, the pVHL-RPS3 association interferes with the interaction between RPS3 and RPS2. Expression of pVHL also leads to nuclear retention of pre-40S ribosomal subunits, diminishing polysomes and 18S rRNA levels. We also demonstrate that pVHL suppresses both cap-dependent and cap-independent protein synthesis. Our findings unravel a novel function of pVHL and provide insight into the regulation of ribosome biogenesis by the tumor suppressor pVHL.

[Multi Scenario Carbon Peak Prediction and Emission Reduction Path Analysis of Xi'an Hi-tech Zone].

The fifth session of the 13th National People's Congress proposed to be committed to promoting carbon peaking and carbon neutrality, promoting the comprehensive green and low-carbon transformation of the economy and society and achieving high-quality development. As an important scientific and technological innovation and industrial cluster in Shaanxi Province, the economic development of the Xi'an Hi-tech Zone largely relies on energy consumption, making the task of carbon reduction particularly challenging. Firstly, taking the Xi'an Hi-tech Zone as the research object, through systematic accounting of carbon emissions within the park, we analyzed the current carbon emission status of enterprises in different energy types and industries. Then, using the Kaya model, multiple independent carbon peak scenarios were set up to predict the total carbon emissions and peak time under different scenarios. Finally, based on the development characteristics of the Xi'an Hi-tech Zone, we scientifically selected corresponding carbon emission reduction paths and provided reasonable emission reduction suggestions. The results showed that the proportion of carbon emissions consumed by electricity was currently the highest, and the share was increasing yearly. Industrial carbon emissions had always been dominant, and the development of the tertiary industry was becoming increasingly prosperous. In the scenario prediction, the carbon emission factor scenario, energy intensity scenario, and economic level scenario could reach the carbon peak by 2030. Among them, the economic development level had the greatest impact on the peak and time of the future carbon peak in the Xi'an Hi-tech Zone, whereas the industrial structure scenario, energy source structure scenario, and population size scenario had no peak before 2030. The future emission reduction path mainly started from decarbonization of the power sector, stable and high-quality economic development, green upgrading of energy and industrial structure, and building a green transportation system. This can reserve more preparation time for achieving carbon neutrality and provide decision-making reference for the low-carbon development of industrial parks in China.

AtHO1 is involved in iron homeostasis in an NO-dependent manner.

AtHO1 (HY1) encodes heme oxygenase-1 in Arabidopsis, catalyzing cleavage of heme to biliverdin with the release of iron and carbon monoxide (CO). Our previous study showed that CO as an endogenous component is able to improve plant adaptation to iron deficiency. Here, we performed a genetic study to identify further the putative role of AtHO1 in the iron deficiency response. Iron deficiency induced AtHO1 expression at the transcriptional and translational levels. Evidence has been provided that overexpression of AtHO1 could confer plant tolerance to iron deficiency by improving expression of AtFIT, AtFRO2 and AtIRT1, the activity of ferric-chelate reductase (FCR) and iron accumulation. In contrast, RNA interference with AtHO1 expression in 35S::AntiHO1 plants and the AtHO1 loss-of-function (hy1 mutant) resulted in adverse phenotypes. In 35S::AtHO1 transgenic lines, a higher level of CO and water-soluble iron, and a lower level of heme were identified, suggesting that AtHO1-regulated iron homeostasis was possibly through the catabolism of heme to produce CO and free iron. Because nitric oxide (NO) is known to regulate iron homeostasis in plants, the connection between AtHO1 expression and NO action was examined. AtHO1-overexpressing plants generated more NO, whereas knock-down of AtHO1 expression reduced the level of NO in plants. The NO scavenger cPTIO [2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethylini dazoline-1-oxyl-3-oxide] caused a decrease in AtHO1-induced FCR activity. Under both iron-sufficient and -deficient conditions, administration of the NO donor sodium nitroprusside induced FCR activity in the hy1 plants. These results suggest that AtHO1 is involved in iron homeostasis in an NO-dependent manner.

Low-density solvent-based vortex-assisted surfactant-enhanced emulsification liquid-liquid microextraction and its application.

For the first time, the low-density solvent-based vortex-assisted surfactant-enhanced emulsification liquid-liquid microextraction, followed by GC-flame photometric detection has been developed for the determination of eight organophosphorus pesticides in aqueous samples. A small volume of organic extraction solvent (toluene) was dispersed into the aqueous samples by the assistance of surfactant and vortex agitator. The extraction was performed in a special disposable polyethylene pipette, allowing using the reagents with lower density than water as extraction solvents. The influence parameters were systemically investigated and optimized: toluene (30 µL) and Triton X-100 (0.2 mmol/L) were used as the extraction solvent and the surfactant, respectively, and the extraction was performed for 1 min under room temperature without adding sodium chloride. Under the optimum conditions, the validation parameters such as the RSD (n = 6; 2.1-11.3%), LOD (0.005 and 0.05 µg/L), and linear range (0.1-50.0 µg/L with correlation coefficients (0.9958-0.9992) showed the method was satisfying. The proposed method has been successfully applied to the determination of the organophosphorus pesticides in real samples with recoveries between 82.8 and 100.2%.

[Research progress on periventricular white matter damage pathogenesis in preterm infants].

Periventricular white matter damage is one of the characteristics of brain damage in preterm infants, and it is the most important type of encephalopathy. The pathological changes including the white matter of coagulation necrosis, oligodendrocyte damage, myelin damage, axonal injury and reactive gliosis and microglia infiltration in necrotic areas. All of these lesions are closely related to the nervous system sequelae in later-neonatal period. The pathogenesis of periventricular leukomalacia in premature infants are mainly cause by its immature brain vascular, and precursor oligodendrocytes of the attack of hypoxia, ischemia, infection, oxygen free radicals, inflammatory cytokines, increasing glutamate, and other high-risk factors. In this paper, an overview of progress in the study of the pathogenesis of periventricular white matter damage in premature infants through literature review to provide a theoretical support for clinical prevention, diagnosis and treatment.

Reconstruction of Metal Ions Extracted from Coal Gangue to Synthesize Cost-effective Adsorbent for Highly Efficient Removal of Pollutants.

An emerging "one stone, three birds" strategy was proposed to realize the value-added disposal of solid waste coal gangue (CG), the synthesis of superb adsorbent and the efficient decontamination of pollutants (i. e., dyes, heavy metals). In this process, the metal ions extrated from calcined coal gangue (CCG) was reconstituted by a one-step hydrothermal process to yield porous polymetallic silicate adsorbent (named HECCGA8h). The adsorbent has a high adsorption capacity of 270.27 and 185.53 mg/g for methylene blue (MB) and Cd(II), respectively. In the actual waters, the removal rate of MB by this adsorbent reaches 99.8% (in Yangtze River water) and 99.42% (in Seawater), and the removal rate of Cd(II) reaches 99.11% (in Yangtze River water) and 92.52% (in Seawater), respectively. Thermokinetic analysis showed that the adsorption of MB by HECCGA8h is spontaneous and endothermic with increased entropy, and the adsorption of Cd(II) is spontaneous and exothermic. The adsorption of MB is mainly driven by synergism of hydrogen bond, electrostatic attraction and ion exchange, and the adsorption of Cd(II) is mainly driven by the complexation and ion exchange between the surface group of the adsorbent and Cd(II). This research provides a new way for the realization of "treating waste with waste".

Selection and validation of reference genes for studying stress-related agarwood formation of Aquilaria sinensis.

UNLABELLED: Agarwood is a high-valued woody material for medicine, perfume, and incense production in Asia, Middle East, and Europe. The wild resources of agarwood-producing tree species, e.g., Aquilaria sinensis have been greatly threatened. The formation of agarwood is considered to be associated with the plant stress and defensive responses, thus it would be urgent and significant to investigate the molecular mechanism of these species responding to a variety of stresses. This is the first report regarding the reference gene selection of Aquilaria species for studying the molecular mechanism of stress-related agarwood production. Candidate reference genes were selected according to previous reports and the sequences were obtained from the 454 EST library of A. sinensis. To obtain the robust genes, we applied three independent programs depending on distinct assumptions and combined these results by a rank aggregation algorithm. The result supports tubulin, ribosomal protein, and glyceraldehyde-3-phosphate dehydrogenase to be the most stable reference genes for quantification of target gene expression in the overall samples examined. Validation of these genes through normalizing the expression of a terpene synthase demonstrated that these three genes are reliable. The selective usage of three algorithms based on their characteristics was underlined. However, more robust genes could be identified if the results of all algorithms were combined by a proper method such as the rank aggregation algorithm. KEY MESSAGE: Reference genes which are critical in gene expression studies are recommended for future molecular studies of stress response and agarwood production in the endangered Aquilaria and other tree species.

[Pollution Characteristics and Source Apportionment of Atmospheric Volatile Organic Compounds in Summer in Yuncheng City].

Based on the online monitoring data of VOCs, O3, and NO2 in Yuncheng City from June to August 2020, the pollution characteristics of VOCs in Yuncheng City in summer were analyzed. At the same time, the main emission sources were determined using a PMF model, and the chemical reactivity of VOCs was evaluated using the maximum incremental reactivity (MIR) method and fractional aerosol coefficients (FAC). The results showed that the urban area of Yuncheng was seriously polluted by VOCs and NO2 in the early morning and evening during summer, the peak value of VOCs daily variation occurred at 08:00 and 20:00, respectively, and was mainly affected by the morning and evening peaks in traffic. The ρ(VOCs) from June to August was 50.52 µg·m-3, and the species with the highest proportion were alkanes (39.39%) and oxygenated volatile organic compounds (OVOCs, 34.63%). Five VOCs emission sources were determined by the PMF model, of which the largest contribution was from motor vehicle exhaust emission sources (33.10%), followed by industrial emission sources (29.46%), natural gas and coal combustion sources (17.31%), solvent use sources (11.94%), and plant emission sources (8.19%). Controlling motor vehicle exhaust emission sources is the key to alleviate VOCs pollution in summer in Yuncheng City. The average ozone formation potential (OFP) of VOCs was 162.88 µg·m-3, in which OVOCs had the highest contribution rate (45.37%); acetaldehyde, propionaldehyde, ethylene, isoprene, and toluene were the key active components; and industrial emission sources were the emission sources with the highest contribution rate. The average value of secondary organic aerosol formation potential (SOAp) of VOCs was 0.40 µg·m-3, in which the contribution rate of aromatic hydrocarbons was the highest (88.00%), and the solvent use source was the emission source with the highest contribution rate.