Could early life DHA supplementation benefit neurodevelopment? A systematic review and meta-analysis.

Background: Docosahexaenoic acid (DHA) plays a crucial role in the growth and functional development of the infant brain. However, the impact of additional DHA supplementation on neurodevelopment in infants remains controversial in randomized controlled trials. In this systematic review and meta-analysis, we aimed to investigate the effects of prenatal and postnatal DHA supplementation on neurodevelopment. Methods: We systematically searched the MEDLINE, EMBASE, and Cochrane Library electronic databases using a predefined strategy until 8 February 2024. We extracted relevant study characteristics and outcomes related to the nervous system. Two independent reviewers critically evaluated the included studies to assess their validity and risk of bias. Results: A total of 21 studies met our inclusion criteria, one study was removed after quality assessment, and the meta-analysis included 9 randomized controlled trials. The meta-analysis results indicated that there was no statistically significant difference between the DHA supplementation group and the placebo group, as assessed by the Mental Development Index [MDI; mean difference (MD), 0.41; 95% confidence interval (CI), -0.91 to 1.73; p = 0.55]. However, the DHA group had a significantly higher Psychomotor Development Index (PDI) than the placebo group (MD, 1.47; 95% CI, 0.23 to 2.72; p = 0.02). Subgroup analyses based on populations showed that DHA supplementation was superior to placebo for infants in both MDI (language score conversion; MD, 2.05; 95% CI, -0.16 to 4.26; p = 0.07) and PDI (MD, 1.94; 95% CI, 0.23 to 3.65; p = 0.03). Other subgroup analyses indicated no statistical differences between the two groups. The remaining assessments that could not be summarized quantitatively underwent a narrative evaluation. Conclusion: Based on the BSID assessments, DHA supplementation in infants may have potential neurodevelopmental benefits. Because the meta-analysis included few high-quality articles and had some limitations, more relevant articles are needed to address the need for separate DHA supplementation in infants, pregnant women, and lactating mothers. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022348100, identifier: CRD42022348100.

Response of organic aerosol in Beijing to emission reductions during the XXIV Olympic Winter Games.

Organic aerosol (OA) serves as a crucial component of fine particulate matter. However, the response of OA to changes in anthropogenic emissions remains unclear due to its complexity. The XXIV Olympic Winter Games (OWG) provided real atmospheric experimental conditions on studying the response of OA to substantial emission reductions in winter. Here, we explored the sources and variations of OA based on the observation of aerosol mass spectrometer (AMS) combined with positive matrix factorization (PMF) analysis in urban Beijing during the 2022 Olympic Winter Games. The influences of meteorological conditions on OA concentrations were corrected by CO and verified by deweathered model. The CO-normalized primary OA (POA) concentrations from traffic, cooking, coal and biomass burning during the OWG decreased by 39.8 %, 23.2 % and 65.0 %, respectively. Measures controlling coal and biomass burning were most effective in reducing POA during the OWG. For the CO-normalized concentration of secondary OA (SOA), aqueous-phase related oxygenated OA decreased by 51.8 % due to the lower relative humidity and emission reduction in precursors, while the less oxidized­oxygenated OA even slightly increased as the enhanced atmospheric oxidation processes may partially offset the efficacy of emission control. Therefore, more targeted reduction of organic precursors shall be enhanced to lower atmospheric oxidation capacity and mitigate SOA pollution.

Multiple LDLR class A repeats on very-low-density lipoprotein receptor promote the cross-species transmission of Semliki Forest virus.

Multiple LDLR class A (LA) repeats around LA3 promote synergistic binding to Semliki Forest virus (SFV) E1-DIII near the 2-fold and 5-fold symmetry axes. Meanwhile, the multiple consecutive LAs concatemer shows approximately 1000 times higher binding affinity than that of LA3s, which can help to effectively and synergistically bind with E1-DIII of viral envelope protein.

Pharmacological Activity of Cepharanthine.

Cepharanthine, a natural bisbenzylisoquinoline (BBIQ) alkaloid isolated from the plant Stephania Cephalantha Hayata, is the only bisbenzylisoquinoline alkaloid approved for human use and has been used in the clinic for more than 70 years. Cepharanthine has a variety of medicinal properties, including signaling pathway inhibitory activities, immunomodulatory activities, and antiviral activities. Recently, cepharanthine has been confirmed to greatly inhibit SARS-CoV-2 infection. Therefore, we aimed to describe the pharmacological properties and mechanisms of cepharanthine, mainly including antitumor, anti-inflammatory, anti-pathogen activities, inhibition of bone resorption, treatment of alopecia, treatment of snake bite, and other activities. At the same time, we analyzed and summarized the potential antiviral mechanism of cepharanthine and concluded that one of the most important anti-viral mechanisms of cepharanthine may be the stability of plasma membrane fluidity. Additionally, we explained its safety and bioavailability, which provides evidence for cepharanthine as a potential drug for the treatment of a variety of diseases. Finally, we further discuss the potential new clinical applications of cepharanthine and provide direction for its future development.

A rare early-onset neonatal case of Birk-Barel syndrome presenting severe obstructive sleep apnea: a case report.

Background: Birk-Barel syndrome, also known as KCNK9 imprinting syndrome, is a rare fertility disorder. And the main clinical manifestations include congenital hypotonic, craniofacial malformation, developmental delay, and intellectual disability. Generally, such patients could be diagnosed beyond the infant period. Moreover, the delayed diagnosis might lead to a poor prognosis of rehabilitation therapy. However, neonatal obstructive sleep apnea (OSA) was seldom reported in Birk-Barel syndrome. Here, we reported a severe neonatal OSA case induced by Birk-Barel syndrome, resulting in an early diagnosis with improved outcomes by integrative management. Case presentation: The proband was a neonate presenting with recurrent severe OSA, with craniofacial deformity and congenital muscle hypotonia. Bronchoscopy examinations indicated a negative finding of pharyngeal and bronchus stenosis, while laryngomalacia had been observed. Whole exon sequencing demonstrated a c. 710C>A heterozygous variant resulting in a change of amino acid (p.A237D). This variant resulted in a change of amino acid sequence, affected protein features and changed splice site leading to a structural deformation in KCNK9 protein. This p.A237D variant also affected the crystal structure on the p.G129 site. Additionally, we used the mSCM tool to measure the free energy changes between wild-type and mutant protein, which indicated highly destabilizing (-2.622 kcal/mol). Conclusion: This case report expands the understanding of Birk-Barel syndrome and indicates that OSA could serve as the on-set manifestation of Birk-Barel syndrome. This case emphasized genetic variants which were associated with severe neonatal OSA. Adequate WES assessment promotes early intervention and improves the prognosis of neurological disorders in young children.

Drivers of High Concentrations of Secondary Organic Aerosols in Northern China during the COVID-19 Lockdowns.

During the COVID-19 lockdown in early 2020, observations in Beijing indicate that secondary organic aerosol (SOA) concentrations increased despite substantial emission reduction, but the reasons are not fully explained. Here, we integrate the two-dimensional volatility basis set into a state-of-the-art chemical transport model, which unprecedentedly reproduces organic aerosol (OA) components resolved by the positive matrix factorization based on aerosol mass spectrometer observations. The model shows that, for Beijing, the emission reduction during the lockdown lowered primary organic aerosol (POA)/SOA concentrations by 50%/18%, while deteriorated meteorological conditions increased them by 30%/119%, resulting in a net decrease in the POA concentration and a net increase in the SOA concentration. Emission reduction and meteorological changes both led to an increased OH concentration, which accounts for their distinct effects on POA and SOA. SOA from anthropogenic volatile organic compounds and organics with lower volatility contributed 28 and 62%, respectively, to the net SOA increase. Different from Beijing, the SOA concentration decreased in southern Hebei during the lockdown because of more favorable meteorology. Our findings confirm the effectiveness of organic emission reductions and meanwhile reveal the challenge in controlling SOA pollution that calls for large organic precursor emission reductions to rival the adverse impact of OH increase.

Molecular tracers, mass spectral tracers and oxidation of organic aerosols emitted from cooking and fossil fuel burning sources.

Secondary organic aerosol (SOA) composes a substantial fraction of atmospheric particles, yet the formation and aging mechanism of SOA remains unclear. Here we investigate the initial oxidation of primary organic aerosol (POA) and further aging of SOA in winter Beijing by using aerosol mass spectrometer (AMS) measurements along with offline molecular tracer analysis. Multilinear engine (ME-2) source apportionment was conducted to capture the characteristic of source-related SOA, and connect them with specific POA. Our results show that urban cooking and fossil fuel burning sources contribute significantly (17 % and 20 %) to total organic aerosol (OA) in winter Beijing. Molecular tracer analysis by two-dimensional gas chromatography-time-of-flight mass spectrometer (GC × GC-ToF-MS) reveals that cooking SOA (CSOA) is produced through both photooxidation and aqueous-phase processing, while less oxidized SOA (LO-SOA) is the photooxidation product of fossil fuel burning OA (FFOA) and may experience aqueous-phase aging to form more-oxidized oxygenated OA (MO-OOA). Furthermore, CHOm/z 69 and CHOm/z 85 are mass spectral tracers indicating the initial photooxidation, while CHO2+ and C2H2O2+ imply further aqueous-phase aging of OA. Tracer analysis indicates that the formation of diketones is involved in the initial photooxidation of POA, while the formation of glyoxal and diacids is involved in the further aqueous-phase aging of SOA.

Long COVID: The latest manifestations, mechanisms, and potential therapeutic interventions.

COVID-19 caused by SARS-CoV-2 infection affects humans not only during the acute phase of the infection, but also several weeks to 2 years after the recovery. SARS-CoV-2 infects a variety of cells in the human body, including lung cells, intestinal cells, vascular endothelial cells, olfactory epithelial cells, etc. The damages caused by the infections of these cells and enduring immune response are the basis of long COVID. Notably, the changes in gene expression caused by viral infection can also indirectly contribute to long COVID. We summarized the occurrences of both common and uncommon long COVID, including damages to lung and respiratory system, olfactory and taste deficiency, damages to myocardial, renal, muscle, and enduring inflammation. Moreover, we provided potential treatments for long COVID symptoms manifested in different organs and systems, which were based on the pathogenesis and the associations between symptoms in different organs. Importantly, we compared the differences in symptoms and frequency of long COVID caused by breakthrough infection after vaccination and infection with different variants of concern, in order to provide a comprehensive understanding of the characteristics of long COVID and propose improvement for tackling COVID-19.

2'-Fucosyllactose Inhibits Coxsackievirus Class A Type 9 Infection by Blocking Virus Attachment and Internalisation.

Coxsackieviruses, a genus of enteroviruses in the small RNA virus family, cause fatal infectious diseases in humans. Thus far, there are no approved drugs to prevent these diseases. Human milk contains various biologically active components against pathogens. Currently, the potential activity of breast milk components against the coxsackievirus remains unclear. In our study, the inhibitory effect of 16 major human milk components was tested on coxsackievirus class A type 9 isolate (CV-A9), BUCT01; 2'-Fucosyllactose (2'-FL) was identified to be effective. Time-of-addition, attachment internalisation assays, and the addition of 2'-FL at different time points were applied to investigate its specific role in the viral life cycle. Molecular docking was used to predict 2'-FL's specific cellular targets. The initial screening revealed a significant inhibitory effect (99.97%) against CV-A9 with 10 mg/mL 2'-FL, with no cytotoxicity observed. Compared with the control group, 2'-FL blocked virus entry (85%) as well as inhibited viral attachment (48.4%) and internalisation (51.3%), minimising its infection in rhabdomyosarcoma (RD) cells. The cell pre-incubation with 2'-FL exhibited significant inhibition (73.2-99.9%). Extended incubation between cells with 2'-FL reduced CV-A9 infection (93.9%), suggesting that 2'-FL predominantly targets cells to block infection. Molecular docking results revealed that 2'-FL interacted with the attachment receptor αvß6 and the internalisation receptor FCGRT and ß2M with an affinity of -2.14, -1.87, and -5.43 kcal/mol, respectively. This study lays the foundation for using 2'-FL as a food additive against CV-A9 infections.

Efficacy and Safety of Various First-Line Therapeutic Strategies for Fetal Tachycardias: A Network Meta-Analysis and Systematic Review.

Background: Fetal arrhythmias are common cardiac abnormalities associated with high mortality due to ventricular dysfunction and heart failure, particularly when accompanied by hydrops. Although several types of common fetal tachycardias have been relatively identified medications, such as digoxin, flecainide, and sotalol, there is no first-line drug treatment protocol established for the treatment of various types of fetal tachycardias. Methods: We conducted a network meta-analysis using a Bayesian hierarchical framework to obtain a model for integrating both direct and indirect evidence. All tachycardia types (Total group), supraventricular tachycardia (SVT subgroup), atrial flutter (AF subgroup), hydrops subgroup, and non-hydrops subgroup fetuses were analyzed, and five first-line regimens were ranked according to treatment outcomes: digoxin monotherapy (D), flecainide monotherapy (F), sotalol monotherapy (S), digoxin plus flecainide combination therapy (DF), and digoxin plus sotalol combination therapy (DS). Effectiveness and safety were determined according to the cardioversion rate and intrauterine death rate. Results: The pooled data indicated that DF combination therapy was always superior to D monotherapy, regardless of the tachycardia type or the presence of hydrops: Total, 2.44 (95% CrI: 1.59, 3.52); SVT, 2.77 (95% CrI: 1.59, 4.07); AF, 67.85 (95% CrI: 14.25, 168.68); hydrops, 6.03 (95% CrI: 2.54, 10.68); and non-hydrops, 5.06 (95% CrI: 1.87, 9.88). DF and F had a similar effect on control of fetal tachycardias. No significant differences were observed when comparing S, DS with D therapies across the subgroup analyses for the SVT, hydrops, and non-hydrops groups. No significant differences in mortality risks were among the various treatment regimens for the total group. And no significant differences were found in rates of intrauterine death rates at the same cardioversion amount. Conclusion The flecainide monotherapy and combination of digoxin and flecainide should be considered the most superior therapeutic strategies for fetal tachycardia. Systematic Review Registration: (https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=288997), identifier (288997).

Overview of Breastfeeding Under COVID-19 Pandemic.

During the global pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), pregnant and lactating women are at higher risk of infection. The potential of viral intrauterine transmission and vertical transmission by breastfeeding has raised wide concerns. Breastmilk is rich in nutrients that contribute to infant growth and development, and reduce the incidence rate of infant illness and death, as well as inhibit pathogens significantly, and protect infants from infection. Although it is controversial whether mothers infected with COVID-19 should continue to breastfeed, many countries and international organizations have provided recommendations and guidance for breastfeeding. This review presents the risks and benefits of breastfeeding for mothers infected with COVID-19, and the reasons for the absence of SARS-CoV-2 active virus in human milk. In addition, the antiviral mechanisms of nutrients in breastmilk, the levels of SARS-CoV-2 specific antibodies in breastmilk from COVID-19 infected mothers and vaccinated mothers are also summarized and discussed, aiming to provide some support and recommendations for both lactating mothers and infants to better deal with the COVID-19 pandemic.

A narrative review on the research progress of gonadal function protection in children with cancer.

Background and Objective: The global incidence of malignant tumors in children (0-14 years) and adolescents (15-19 years) ranges between 95 per 1 million and 255 per 1 million, which seriously affects the survival of patients. In the past 30 years, with the application of comprehensive treatments (including surgery, chemotherapy, radiotherapy, and bone marrow transplantation), great progress has been made in the treatment of malignant tumors in children and adolescents. The 5-year survival rate now exceeds 80%, and most patients can smoothly enter adolescence or the reproductive period. However, due to the particular age of patients with malignant tumors in children and adolescents, treatment may cause abnormal growth of the patient's height, bones, and some vital organs (such as the pituitary gland and reproductive organs). Treatment may also cause abnormal secretion of growth hormones, thyroid hormones, and sex hormones. These complications seriously affect the quality of life of tumor patients. In the past ten years, countries have established long-term follow-up specifications for children with tumors. These programs have found that, in adulthood, 67% to 75% of children who survived having tumors have at least one treatment-related complication. Among patients receiving chemotherapy, gonadal dysfunction is the most common related endocrine dysfunction. Methods: This paper reviews the literature on fertility protection services for cancer patients in foreign countries was conducted to provide a reference for developing gonadal protection services for cancer patients and for establishing consensus or guidelines on gonadal protection in China. Key Content and Findings: In the treatment of childhood cancer, the assistance of reproductive technology can effectively reduce the occurrence of complications from treatment. Conclusions: Therefore, minimizing the effects of radiotherapy and chemotherapy on the growth and endocrine of children and adolescents while treating tumors is a new challenge for oncologists.

A novel frameshift mutation of DVL1-induced Robinow syndrome: A case report and literature review.

BACKGROUND: Robinow syndrome is a rare genetic disorder that affects the development of multiple systems. Due to its low prevalence and diversity of phenotypic presentation it has been challenging to definitively characterize features of Robinow syndrome. METHODS: We performed DNA extraction, whole-exome sequencing analysis, and mutation analysis of DVL1 to obtain genetic data on the patient. We subsequently analyzed the patient's clinical and genetic data. RESULTS: The proband was a 3-month-old female infant who suffered from significant global developmental delay and metabolic disorder. The main clinical manifestations included facial dysmorphisms, bilateral dislocation of the hip joint, and hearing impairment. Whole-exome sequencing of the patient's DNA revealed a heterozygous mutation of c.1620delC in DVL1. Analysis with the MutationTaster application indicated that both were pathogenic (probability = 1), causing frameshift mutations affecting 107 amino acids (p.S542Vfs*107). Significant structural changes were identified in the amino acid sequence after the WNT signaling-related DEP domain site was predicted using the AlphaFold Protein structure database. The stability of the three main domains was then evaluated using SWISS-MODEL, and indicated that the mutation did not alter the DIX, PDZ, or DEP domain sequences. Because all reported pathogenic mutations were located near the DEP domain, we speculated that structural changes around the DEP domain may have impaired WNT domain function and WNT signaling, resulting in Robinow syndrome. CONCLUSION: The present case suggests that molecular genetic screening is useful for the diagnosis of developmental disorders, particularly in children with a positive family history. In the current patient all the related pathological variants were located within a narrow locus. This report expands the known manifestations of Robinow syndrome and contributes to refinement of its molecular basis.

Variations and Sources of Organic Aerosol in Winter Beijing under Markedly Reduced Anthropogenic Activities During COVID-2019.

The COVID-19 outbreak provides a "controlled experiment" to investigate the response of aerosol pollution to the reduction of anthropogenic activities. Here we explore the chemical characteristics, variations, and emission sources of organic aerosol (OA) based on the observation of air pollutants and combination of aerosol mass spectrometer (AMS) and positive matrix factorization (PMF) analysis in Beijing in early 2020. By eliminating the impacts of atmospheric boundary layer and the Spring Festival, we found that the lockdown effectively reduced cooking-related OA (COA) but influenced fossil fuel combustion OA (FFOA) very little. In contrast, both secondary OA (SOA) and O3 formation was enhanced significantly after lockdown: less-oxidized oxygenated OA (LO-OOA, 37% in OA) was probably an aged product from fossil fuel and biomass burning emission with aqueous chemistry being an important formation pathway, while more-oxidized oxygenated OA (MO-OOA, 41% in OA) was affected by regional transport of air pollutants and related with both aqueous and photochemical processes. Combining FFOA and LO-OOA, more than 50% of OA pollution was attributed to combustion activities during the whole observation period. Our findings highlight that fossil fuel/biomass combustion are still the largest sources of OA pollution, and only controlling traffic and cooking emissions cannot efficiently eliminate the heavy air pollution in winter Beijing.

A narrative review of mechanisms of ferroptosis in cancer: new challenges and opportunities.

OBJECTIVE: This article reviews the specific mechanism of ferroptosis in cancer and introduces in detail the opportunities and challenges of ferroptosis-based cancer therapy, aiming to provide a new research direction for tumor therapy. BACKGROUND: Ferroptosis is a newly discovered programmed non-apoptotic form of cell death. Involving changes in metabolic processes and the accumulation of peroxidation caused by factors such as drugs or genes which destruct the cell membrane structure, this kind of cell death has been linked with the pathological process of diseases such as tumors, neurological diseases, ischemia-reperfusion injury, kidney injury, and hemopathy. This kind of cell death can play a vital role in inhibiting tumorigenesis by eliminating the adaptive characteristics of malignant cells and removing cells that are unable to obtain key nutritional factors or are infected and damaged by environmental changes. The present focus of research on the regulation of ferroptosis-related diseases involves the use of small molecule compounds. METHODS: We described the mechanism of ferroptosis and its related small molecules compounds, which involved in the regulatory mechanism, and analyzed the role and regulatory mechanism of ferroptosis in different tumors. CONCLUSIONS: This article reviewed the mechanism of ferroptosis and its role and mechanism in different tumors, and showed it can inhibit the occurrence and development of different tumors and may reduce the adverse effects of current treatment methods.

A case report of precocious puberty related to Rett syndrome and a literature review.

Rett syndrome is an X-linked dominant disorder, and the typical phenotype includes intractable epileptic seizures and severe mental retardation, in particular, a rapid regression in language and limited progress in psychomotor development. Premature breast and pubic hair development and advanced bone age are signs of precocious puberty (PP), defined as puberty occurring before 8 years of age in girls. There are rare reports about precious puberty associated with Rett syndrome. Herein, we report the case of a patient with Rett syndrome with precocious puberty. Her first signs of PP occurred 6 months prior to presentation (at 7.5 years old), and the laboratory measurements, including tests of bone age and gonadotropin-releasing hormone stimulation, were positive for PP. PP was controlled after treatment with leuprorelin 3.75 mg for one year. In addition, the genetic and phenotypic spectrum of previously reported cases of Rett syndrome with precocious puberty are reviewed and summarized.

Menkes disease diagnosed by a novel ATP7A frameshift mutation in a patient with infantile spasms-a case report.

Menkes disease (MD) is a rare congenital copper deficiency disease caused by an adenosine triphosphatase copper transporting alpha (ATP7A) gene mutation. It is a progressive and systemic disease that primarily involves the central nervous system and connective tissues. The clinical manifestation of these patients with MD is curly hair, progressive muscle tone reduction, and convulsions, and often leads to death in early infancy. Herein, we present a case of a 9-month-old Chinese male who displayed developmental regression, followed by convulsions, which were characterized by infantile spasms (ISs). The proband also had curly hair, hypopigmented skin, cutis laxa, decreased muscle tone, and micrognathia. The patient's ceruloplasmin levels were below the reference values. Brain magnetic resonance imaging (MRI) showed abnormal signals bilaterally that were symmetrically distributed in the caudate nucleus, globus pallidus, and subcortical white matter of the temporal parietal cortex, white matter in the anterior and posterior corners of the ventricles and the anterior limb of the internal capsule. The electroencephalograph (EEG) showed hypsarrhythmia. Genetic testing revealed a novel frameshift mutation in the ATP7A gene exon 13 and premature termination codon. Copper replacement therapy was initiated after the delayed diagnosis was established. However, the patient still died several months later due to disease progression. Our case reveals a novel frameshift mutation of the ATP7A gene, which expands the gene spectrum of MD. The infants with uncontrollable convulsions, regressive development, curly hair, MD should be considered at early stage and also need the further genetic analysis to confirm MD finally. The correct and timely diagnosis and initiating copper replacement therapy may improve the prognosis.

Health Benefits and Costs of Clean Heating Renovation: An Integrated Assessment in a Major Chinese City.

China has been promoting one of the world's largest campaigns for clean heating renovation since 2017. Here, we present an integrated cost-benefit analysis in a major prefecture-level city by combining a large-scale household energy survey and PM2.5 exposure measurement, high-resolution chemical transport simulation, and health impact assessment. We find that the completed renovation decreases the share of solid fuels in the heating energy mix from 96 to 6% and achieves a concomitant reduction of cooking solid-fuel use by 70%. The completed renovation decreases the ambient PM2.5 concentration in Linfen by 0.5-5 µg m-3 (2.4 µg m-3 on average) and decreases the integrated PM2.5 exposure by 4.2 (3.5-5.0) µg m-3. The renovation is estimated to avoid 162 (125-225) and 328 (254-457) premature deaths annually based on two health impact assessment methods. The ratios of monetized health benefits to cost are 1.51 (0.73-2.59) and 3.06 (1.49-5.23) based on the above two methods. The benefit-to-cost ratio is projected to remain high if the renovation is further expanded. More polluted and less wealthy households enjoy larger health benefits but also experience a higher expense increase, suggesting that a more carefully designed subsidy policy is needed to protect low-income households.

Chemical characteristics and sources of water-soluble organic aerosol in southwest suburb of Beijing.

PM2.5 filter sampling and components measurement were conducted in autumn and winter from 2014 to 2015 at a suburban site (referred herein as "LLH site") located in the southwest of Beijing. The offline aerosol mass spectrometry (offline-AMS) analysis and positive matrix factorization (PMF) were applied for measurement and source apportionment of water-soluble organic aerosol (WSOA). Organic aerosol (OA) always dominated PM2.5 during the sampling period, especially in winter. WSOA pollution was serious during the polluted period both in autumn (31.1 µg/m3) and winter (31.9 µg/m3), while WSOA accounted for 54.4% of OA during the polluted period in autumn, much more than that (21.3%) in winter. The oxidation degree of WSOA at LLH site was at a high level (oxygen-to-carbon ratio, O/C=0.91) and secondary organic aerosol (SOA) contributed more mass ratio of WSOA than primary organic aerosol (POA) during the whole observation period. In winter, coal combustion OA (CCOA) was a stable source of OA and on average accounted for 25.1% of WSOA. In autumn, biomass burning OA (BBOA) from household combustion contributed 38.3% of WSOA during polluted period. In addition to oxygenated OA (OOA), aqueous-oxygenated OA (aq-OOA) was identified as an important factor of SOA. During heavy pollution period, the mass proportion of aq-OOA to WSOA increased significantly, implying the significant SOA formation through aqueous-phase process. The result of this study highlights the concentration on controlling the residential coal and biomass burning, as well as the research needs on aqueous chemistry in OA formation.

A solvatochromic AIE tetrahydro[5]helicene derivative as fluorescent probes for water in organic solvents and highly sensitive sensors for glyceryl monostearate.

In this paper, a tetrahydro[5]helicene-based imide dye with thienyl group (THID) was studied on its solvatochromism and aggregation-induced emission (AIE) properties by dissolved in various organic solvents. The linear relationship between Stokes shift and aprotic solvent polarity parameter was well fitted with Lippert-Mataga model. Furthermore, Stokes shift also were positively correlated with the normalized molar electronic transition energy, suggested that THID exceptionally depends on solvent polarity for twisted intramolecular charge transfer. In addition, THID demonstrated typical AIE features when adding large amounts of water into good solvent. Meanwhile, it can function as intensity and wavelength-based fluorescence sensor for detecting low-level water content in water soluble solvents, even the low of detection was 0.014 vol% in ACN. Therefore, a simple and highly selective fluorescence analysis for glyceryl monostearate has been established on basis of its AIE property.