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A robust route to synthetic pheomelanin gives insight into the electronic, molecular and supramolecular structure of the natural product, further advancing our understanding of this important subfamily of melanin.

Melanin, a widespread pigment found in many taxa, is widely recognized for its high refractive index, ultraviolet (UV) protection, radical quenching ability, metal binding, and many other unique properties. The aforementioned characteristic traits make melanin a potential candidate for biomedical, separation, structural coloration, and space applications. However, the commercially available natural (sepia) and synthetic melanin are very expensive, limiting their use in various applications. Additionally, eumelanin has been the primary focus in most of these studies. In the present study, we demonstrate that melanin can be extracted from the pathogenic black knot fungus Apiosporina morbosa with a yield of ∼10% using the acid–base extraction method. The extracted melanin shows irregular morphology. Chemical characterization using X-ray photoelectron spectroscopy, infrared spectroscopy, and solid-state nuclear magnetic resonance spectroscopy reveals that the melanin derived from black knots is the less explored nitrogen-free allomelanin. Additionally, the extracted melanin shows broadband UV absorption typical of other types of melanin. Because of the wide availability and low cost of black knots and the invasive nature of the fungus, black knots can serve as an alternative green source for obtaining allomelanin at a low cost, which could stimulate its use as an UV light absorber and antioxidant in cosmetics and packaging industries.

Melanin is ubiquitous in living organisms across different biological kingdoms of life, making it an important, natural biomaterial. Its presence in nature from microorganisms to higher animals and plants is attributed to the many functions of melanin, including pigmentation, radical scavenging, radiation protection, and thermal regulation. Generally, melanin is classified into five types-eumelanin, pheomelanin, neuromelanin, allomelanin, and pyomelanin-based on the various chemical precursors used in their biosynthesis. Despite its long history of study, the exact chemical makeup of melanin remains unclear, and it moreover has an inherent diversity and complexity of chemical structure, likely including many functions and properties that remain to be identified. Synthetic mimics have begun to play a broader role in unraveling structure and function relationships of natural melanins. In the past decade, polydopamine, which has served as the conventional form of synthetic eumelanin, has dominated the literature on melanin-based materials, while the synthetic analogues of other melanins have received far less attention. In this perspective, we will discuss the synthesis of melanin materials with a special focus beyond polydopamine. We will emphasize efforts to elucidate biosynthetic pathways and structural characterization approaches that can be harnessed to interrogate specific structure-function relationships, including electron paramagnetic resonance (EPR) and solid-state nuclear magnetic resonance (ssNMR) spectroscopy. We believe that this timely Perspective will introduce this class of biopolymer to the broader chemistry community, where we hope to stimulate new opportunities in novel, melanin-based poly-functional synthetic materials.

Ursolic acid (UA), found widely in nature, exerts effective anti-tumoral activity against various malignant tumors. However, the low water solubility and poor bioavailability of UA have greatly hindered its translation to the clinic. To overcome these drawbacks, a simple redox-sensitive UA polymeric prodrug was synthesized by conjugating UA to polyethylene glycol using a disulfide bond. This formulation can self-assemble into micelles (U-SS-M) in aqueous solutions to produce small size micelles (∼62.5 nm in diameter) with high drug loading efficiency (∼16.7%) that exhibit pH and reduction dual-sensitivity. The cell and animal studies performed using the osteosarcoma MG-63 cell line and MG-63 cancer xenograft mice as the model systems consistently confirmed that the U-SS-M formulation could significantly prolong the circulation in blood and favor accumulation in tumor tissue. Targeted accumulation allows the U-SS-M to be effectively internalized by cancer cells, where the rapid release of UA is favored by a glutathione-rich and acidic intracellular environment, and ultimately achieves potent antitumor efficacy.

Structurally colored supraparticles, formed from dispersed nanoparticle building blocks through self-assembly, have tremendous potential for applications in displays, coatings, paints, inks, and co...

Objectives: Psychological capital plays an important role in the improvement of mental health. However, the mediating role of psychological capital between job burnout and mental problems has rarely been addressed. This study aims to explore the association between burnout and anxiety and depression symptoms, and the mediating role of psychological capital in this association among managers in eastern China. Methods: A total of 969 managers were recruited to complete a structured questionnaire consisting of items from demographic characteristics, job burnout, anxiety, to depression symptoms using the Maslach Burnout Inventory-General Survey, Generalized Anxiety Disorder Scale, Patient Health Questionnaire-9, and psychological capital scale. The associations between burnout, psychological capital, depression, and anxiety symptoms using multivariate linear regression models. The significance of the mediation effect was calculated using the Sobel test.Results: A total of 969 participants were recruited. The average scores of burnout, psychological capital, depression, and anxiety symptoms were (36.6±14.9), (4.7±0.7), (5.0±4.5), and (6.1±4.9), respectively. Job burnout was positively associated with depression and anxiety symptoms (P < 0.001), and negatively associated with psychological capital (r = -0.46, P < 0.001). Psychological capital mediated the association between job burnout and depression symptoms (P = 0.02). Conclusions: Our findings contribute to the understanding the mediating role of psychological capital in the association between job burnout and depression. Interventions are needed to improve positive psychological capital for the management of the burnout and mental problems among managers.

Recent reports suggest that next-generation hair dyes might take inspiration from the natural pigment melanin. In humans, melanin imparts color to hair and skin and acts as a natural sunscreen and ...

Melanins are a family of heterogeneous biopolymers found ubiquitously across plant, animal, bacterial, and fungal kingdoms where they act variously as pigments and as radiation protection agents. There exist five multifunctional yet structurally and biosynthetically incompletely understood varieties of melanin: eumelanin, neuromelanin, pyomelanin, allomelanin, and pheomelanin. Although eumelanin and allomelanin have been the focus of most radiation protection studies to date, some research suggests that pheomelanin has a better absorption coefficient for X-rays than eumelanin. We reasoned that if a selenium enriched melanin existed, it would be a better X-ray protector than the sulfur-containing pheomelanin because the X-ray absorption coefficient is proportional to the fourth power of the atomic number (Z). Notably, selenium is an essential micronutrient, with the amino acid selenocysteine being genetically encoded in 25 natural human proteins. Therefore, we hypothesize that selenomelanin exists in nature, where it provides superior ionizing radiation protection to organisms compared to known melanins. Here we introduce this novel selenium analogue of pheomelanin through chemical and biosynthetic routes using selenocystine as a feedstock. The resulting selenomelanin is a structural mimic of pheomelanin. We found selenomelanin effectively prevented neonatal human epidermal keratinocytes (NHEK) from G2/M phase arrest under high-dose X-ray irradiation. Provocatively, this beneficial role of selenomelanin points to it as a sixth variety of yet to be discovered natural melanin.

Melanin is a central polymer in living organisms, yet our understanding of its molecular structure remains unresolved. Here, we apply a biosynthetic approach to explore the composite structures accessible in one type of melanin, eumelanin. Using a combination of solid-state NMR, dynamic nuclear polarization, and electron microscopy, we reveal how a variety of monomers are enzymatically polymerized into their corresponding eumelanin pigments. We demonstrate how this approach can be used to unite structure with an understanding of enzymatic activity, substrate scope, and the regulation of nanostructural features. Overall, this data reveals how intermediate metabolites of the Raper–Mason metabolic pathway contribute to polymerization, allowing us to revisit the original proposal of how eumelanin is biosynthesized., Melanin is a central polymer in living organisms, yet our understanding of its molecular structure remains unresolved.

Xanthomonas oryzae pv. oryzicola (Xoc) depends on its type III secretion system (T3SS) to translocate type III secreted effectors (T3SEs), including transcription activator-like effectors (TALEs) and non-transcription activator-like effectors (non-TALEs), into host cells. T3SEs can promote the colonization of Xoc and contribute to virulence by manipulating host cell physiology. We annotated 25 genes encoding non-TALEs in Xoc strain GX01, an isolate from Guangxi in the South China's rice growing region. Through systematic mutagenesis of non-TALEs, we found that xopN, the virulence contribution of which was previously unknown for Xoc, significantly contributes to the virulence of Xoc GX01, as does avrBs2.

Although melanin is one of the most ubiquitous polymers in living systems, our understanding of its molecular structure, biosynthesis and biophysical properties has been limited to only a small number of organisms other than humans. This is in part due to the difficulty associated with isolating pure melanin. While purification methods exist, they typically involve harsh treatments with strong acid/base conditions combined with elevated temperatures that can lead to the polymer backbone degradation. To be successful, a viable isolation method must deliver a selective, yet complete degradation of non-melanin biopolymers as well as remove small molecule metabolites that are not integrative to the melanin backbone. Here, we demonstrate the use of chemoenzymatic processing guided by fluorescent probes for the purification and isolation of native mammalian melanin without significant induction of chemical degradation. This multi-step purification-tracking methodology enables quantitative isolation of pure melanin from mammalian tissue for spectroscopic characterization.

In this paper, the kinetics and thermodynamics of Adenosine 5'-monophosphate (AMP) sorption on the sediments obtained from the Yangtze River Estuary and adjacent areas were studied, in combination with the effects of the sediments' properties and media conditions. The kinetics curves could be described by a two-compartment first-order equation, and the equilibrium isotherms fitted well with the modified Langmuir and Freundlich models. The analysis of organic phosphorus (OP) fractions changes after sorption indicated that the contents of exchangeable or loosely sorbed P

Objectives: The study objective is to assess personality traits as predictors of mental symptoms in university volunteers in China. Methods: We carried out a cross-sectional study. The study sample consisted of volunteers from sixteen main universities in the city of Hangzhou. The OQ-45 scale was used to evaluate mental symptoms and the PHI was used for the measurement of personality traits. Multiple linear regression analysis was used to study relationships between personality factors and mental symptoms. Results: Estimation of personality traits revealed higher scores on subscales of hypomania, depression, and psychopathic deviance. The OQ-45 scale identified 1.4% of volunteers as having psychological disorders. PHI scores were positively correlated with scores on the OQ-45 scale ( P < 0.01). Anxiety was correlated particularly strongly with interpersonal relationship score and total OQ-45 score ( r = 0.6, P < 0.05). Furthermore, we found that personality traits could influence the explicit mental symptoms of the volunteers. Volunteers with traits of anxiety and depression reported a significant impact on their mental symptoms. Conclusions: The OQ-45 and PHI scales can be used to screen volunteers with mental symptoms. Inner personality traits could be used to predict the mental symptoms of volunteers in China. Our results might assist organizers of future conferences and games in selecting appropriate university volunteers. Funding: This study was supported by the Health Commission of Zhejiang Province (2019RC142, OO20190435). Declaration of Interest: The authors declare no competing interest. Ethical Approval: All participants provided written informed consent. This study was carried out according to the Declaration of Helsinki and was approved by the Ethics Committee of Affiliated Mental Health Center & Hangzhou Seventh People's Hospital, Zhejiang University School of Medicine (Code No. 10; date of approval: August 8, 2018).

Anaerobic digestion (AD) has been widely applied for treating organic waste and is known as a carbon-offsetting process. However, most studies relied on laboratory-scale experiments or literature to calculate carbon emissions from AD process, and the impact of digestate processing was overlooked. This study assessed the carbon footprint for an industrial food waste co-digestion plant with operational data. The results indicated that carbon emission before digestate treatment is -88.5 ± 4.4 kg CO

Background Xanthomonas oryzae (Xo) is one of the important pathogenic bacterial groups affecting rice production. Its pathovars Xanthomonas oryzae pv. oryzae (Xoo) and Xanthomonas oryzae pv. oryzicola (Xoc) cause bacterial blight and bacterial leaf streak in rice, respectively. Xo infects host plants by relying mainly on its transcription activator-like effectors (TALEs) that bind to host DNA targets, named effector binding elements (EBEs), and induce the expression of downstream major susceptibility genes. Blocking TALE binding to EBE could increase rice resistance to the corresponding Xo. Findings We used CRISPR/Cas9 to edit the EBEs of three major susceptibility genes (OsSWEET11, OsSWEET14 and OsSULTR3;6) in the rice varieties Guihong 1 and Zhonghua 11. Both varieties have a natural one-base mutation in the EBE of another major susceptibility gene (OsSWEET13) which is not induced by the corresponding TALE. Two rice lines GT0105 (from Guihong 1) and ZT0918 (from Zhonghua 11) with target mutations and transgene-free were obtained and showed significantly enhanced resistance to the tested strains of Xoo and Xoc. Furthermore, under simulated field conditions, the morphology and other agronomic traits of GT0105 and ZT0918 were basically the same as those of the wild types. Conclusions In this study, we first reported that the engineering rice lines obtained by editing the promoters of susceptibility genes are resistant to Xoo and Xoc, and their original agronomic traits are not affected.

Fatty acid and polyketide synthases catalyze the same core reactions. They utilize an acyl carrier protein (ACP), a small four-helix bundle protein, to covalently tether all substrates and intermediates. ACP plays an active role, interacting with both tethered substrates and partner enzymes. Research published in the last decade has helped us to further understand the molecular nature of these interactions and highlights the similarities, differences, and specific protein–protein interactions within primary and secondary ACP-dependent biosynthetic pathways. Herein, we outline the role of the ACP in these pathways and focus on what has been learned about protein–substrate and protein–protein complexes and the interactions responsible for their formation. We focus on new advances in molecular tools and their applications to structural biology and metabolic engineering. These developments will guide future efforts to modify ACP-dependent pathways for next-generation therapeutics, biofuels, and fine chemicals.

Background Increasing evidence has demonstrated that microRNAs regulate the development of cartilage and osteogenesis. Whether miR-206 participates in the development of human articular cartilage remains largely unknown. This study aimed to investigate the role of miR-206 in human chondrocytes. Methods Expression of miR-206 was initially assessed in human osteoarthritis (OA) tissues and articular chondrocytes through quantitative real-time polymerase chain reaction. The effects of miR-206 on proliferation and apoptosis of human chondrocytes were assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) double staining assay. Then, the effects of miR-206 on type II collagen alpha 1 (Col2a1), aggrecan, runt-related transcription factor 2 (RUNX2) and matrix metalloproteinase13 (MMP13) were examined with quantitative real-time polymerase chain reaction and Western blot analysis. Results MiR-206 was significantly increased in human OA tissues and chondrocytes. MiR-206 significantly inhibited the proliferation of chondrocytes, but promoted apoptosis. Expression of Col2a1 and aggrecan were dramatically decreased, and the expression of RUNX2 and MMP13 were significantly increased when miR-206 was overexpressed. Conclusions MiR-206 may participate in cartilage degradation in OA. Manipulation of the expression of miR-206 in human chondrocytes may be a novel therapeutic strategy for the treatment of OA.

Despite much attention, the path of the highly consequential primary proton transfer in the light-driven ion pump bacteriorhodopsin (bR) remains mysterious. Here we use DNP-enhanced magic angle spinning (MAS) NMR to study critical elements of the active site just before the Schiff base (SB) deprotonates (in the L intermediate), immediately after the SB has deprotonated and Asp85 has become protonated (in the M(o) intermediate), and just after the SB has reprotonated and Asp96 has deprotonated (in the N intermediate). An essential feature that made these experiments possible is the 75-fold signal enhancement through DNP. (15)N(SB)–(1)H correlations reveal that the newly deprotonated SB is accepting a hydrogen bond from an alcohol and (13)C–(13)C correlations show that Asp85 draws close to Thr89 before the primary proton transfer. Concurrently, (15)N–(13)C correlations between the SB and Asp85 show that helices C and G draw closer together just prior to the proton transfer and relax thereafter. Together, these results indicate that Thr89 serves to relay the SB proton to Asp85 and that creating this pathway involves rapprochement between the C and G helices as well as chromophore torsion.

Initial bulk density (IBD) is an important variable in anaerobic digestion since it defines and optimizes the treatment capacity of a system. This study reveals the mechanism on how IBD might affect anaerobic digestion of waste. Four different IBD values: D1 (500-700kgm-3), D2 (900-1000kgm-3), D3 (1100-1200kgm-3) and D4 (1200-1400kgm-3) were set and tested over a period of 90days in simulated landfill reactors. The main variables affected by the IBD are the methane generation, saturation degree, extraction of organic matter, and the total population of methanogens. The study identified that IBD >1000kgm-3 may have significant effect on methane generation, either prolonging the lag time or completely inhibiting the process. This study provides a new understanding of the anaerobic digestion process in saturated high-solids systems.

In DNP MAS NMR experiments at ~80–110 K, the structurally important −13CH3 and −15NH3+ signals in MAS spectra of biological samples disappear due to the interference of the molecular motions with the 1H decoupling. Here we investigate the effect of these dynamic processes on the NMR line shapes and signal intensities in several typical systems: (1) microcrystalline APG, (2) membrane protein bR, (3) amyloid fibrils PI3-SH3, (4) monomeric alanine-CD3, and (5) the protonated and deuterated dipeptide N-Ac-VL over 78–300 K. In APG, the three-site hopping of the Ala-Cβ peak disappears completely at 112 K, concomitant with the attenuation of CP signals from other 13C’s and 15N’s. Similarly, the 15N signal from Ala-NH3+ disappears at ~ 173 K, concurrent with the attenuation in CP experiments of other 15N’s as well as 13C’s. In bR and PI3-SH3, the methyl groups are attenuated at ~95 K, while all other 13C’s remain unaffected. However, both systems exhibit substantial losses of intensity at ~243 K. Finally, with spectra of Ala and N-Ac-VL, we show that it is possible to extract site specific dynamic data from the temperature dependence of the intensity losses. Furthermore, 2H labeling can assist with recovering the spectral intensity. Thus, our study provides insight into the dynamic behavior of biological systems over a wide range of temperatures, and serves as a guide to optimizing the sensitivity and resolution of structural data in low temperature DNP MAS NMR spectra.

There is a growing trend toward considering municipal solid waste (MSW) with a large organic fraction as a source of renewable energy using a dry anaerobic digestion (AD) process. Pre-aeration is effective in improving the dry AD of MSW. However, due to a lack of information regarding the modification of organic components during pre-aeration and the relationship with the subsequent AD, the mechanisms and optimum strength of this process remain unclear. In this study, the role of different short-term pre-aeration durations (4, 8, and 14 days) in dry AD of MSW was evaluated in batch-tests, with a focus on changes in the organic components during pre-aeration and their impact on the subsequent spectral evolution of dissolved organic matter (DOM) and bulk performance. Dry AD of MSW operated effectively after the 8-day pre-aeration. The accelerated degradation of proteins during pre-aeration is critical for the subsequent AD, by reducing the organic loading and providing a buffer for the ammonia generated. A favorable methanogenesis, facilitated by pre-aeration, rapidly decreased protein-like fluorescent matter by ∼2.8 times, by converting it to stable humic- and fulvic-like groups. MSW with an 8-day pre-aeration produced the highest biogas yield (192.4 NL/kg dry matter), representing ∼24.9% of the initial carbon recovered as methane. Excessive pre-aeration of 14 days decreased the biogas yield by ∼33%. An insufficient pre-aeration led to an excessive butyric-type acidification, with protein-like matter dominating the bulk DOM (∼81% of total fluorescence intensity). Multivariate analysis methods confirmed that spectroscopic indicators could evaluate the stability of dry AD.

Waste management is a major source of greenhouse gas (GHG) emissions and provides an opportunity to reduce carbon emissions that has yet to be fully exploited. The total GHG emissions in the waste management sector in China is quite different from that in developed countries, mainly due to the high biodegradable fraction (almost 60–70%) of municipal solid waste (MSW). Based on the above characteristics of MSW and its current and future management strategies, five typical scenarios were modeled by the EaseTech software to compare GHG emissions under different scenarios. These strategies were evaluated by life cycle assessment (LCA) and sensitivity analysis. The two scenarios of landfilling, either with LFG flaring or with LFG to energy, would cause very high GHG emissions (259.5 kgCO2-Eq/t and 169.0 kgCO2-Eq/t, respectively) due to the rapid degradation and low efficiency of landfill gas (LFG) collection. Incineration with energy recovery would lower total GHG emissions (−17.5 kgCO2-Eq/t) substantially. However, the auxiliary fuel needed would offset its environmental benefit. Two scenarios, anaerobic digestion (AD) of the source-separated organic fractions and residue landfilling, and AD of the source-separated organic fractions and incineration of the fractions with high calorific value, followed by residue landfilling, would result in significant carbon sinks (−27.7 kgCO2-Eq/t and −54.8 kgCO2-Eq/t, respectively). From the perspective of GHG emissions reduction, the optimum technical route of MSW in China would be AD of the source-separated organic fractions, incineration of the fractions with high calorific value, followed by residue landfilling.

This study explores individual contributions and synergistic effects of food and paper, main components of organic fraction of municipal solid waste (OFMSW) towards volatile fatty acids (VFA) fermentation under different temperatures (25, 37, 42 and 52 °C). Thanks to the synergism of food and paper component (FC & PC), the results revealed that OFMSW is suitable for VFA production. Maximum VFA production was noticed to be 21.5 mg/L at 42 °C, ~2.1, and 1.42 times higher than fermentation of PC and FC. Enhanced hydrolysis of PC occurred at >37 °C, increasing alkalinity in leachate to 6.7 g/L at 42 °C, thus maintaining a stable pH (5.4–5.6) during acidogenic fermentation. Additionally, 74% of COD is hydrolyzed, of which 79% is converted to VFA based on biodegradable carbon at 42 °C. It is suggested that co-existence of FC and PC can enhance VFA production of OFMSW, and targeted VFA production can be maximized through process optimization.

Background: Reproductive characteristics are made up of many complicated physiology procedures that have significant effects on the growth of the buffalo industry and are affected by numerous factors. The ovary is the most important sexual organ of female mammals, and during the oestrous cycles, its corpus luteum (CL) plays a significant part in mammalian reproduction. During the development and regression of corpus luteum, however, the differentially expressed proteins are less defined. In this study, we used a 6-plex tandem mass tag (TMT) strategy for quantitative proteomic comparison of three distinct ovary phases (corpus hemorrhagicum, corpus luteum and corpus hemorrhagicum) in buffalo. Results: A total of 148 differentially expressed proteins were identified, 32 of these proteins were identified as differentially expressed in the group CH (corpus hemorrhagicum) and 116 were identified as differentially expressed in the group CF (corpus fibrosum), with the group CL (corpus luteum) serving as the control group. Notably, we discovered that quite some enzymes such as kinase and phosphatase, are upregulated in the ovary CL phase, and three upregulated enzymes and proteins in the CL phase (PLK1, PGP, and HGS) were verified using Western blotting, quantitative RT-PCR, and immunohistochemistry analysis. The results of these validations were consistent with the quantitative analysis of the TMT-label, which indicated that they could play a crucial role during the CL's reproductive cycle. These buffalo results during the formation and regression of the corpus luteum are also shown to be a substantial reference value for comparable human and mouse studies after analyzing homologous BLAST cross-species. The expression information is accessible with the PXD009957 identifier via ProteomeXchange. Conclusions: Our research gives a deeper understanding of CL formation and regression during the oestrous cycles, which shows kinase and phosphatase regulation, and indicates some potential enzymes and proteins that may influence buffalo fertility. Keywords: corpus luteum, quantitative proteomic, oestrous cycles, ovary, cross-species

Acidogenic fermentation of the organic fraction of municipal solid waste (OFMSW) and its components (food waste, paper waste) was studied in a batch percolator reactor without artificial pH adjustment. The effect of inoculum to substrate ratio on process performance, in terms of pH, hydrolysis and volatile fatty acid (VFA) production, has been investigated. The inoculum to substrate ratio (ISR) was varied from 0 to 0.36 VS/VS and at optimized conditions for fermentation of OFMSW, with ISR 0.23, pH, hydrolysis and acidification yield were 5.5, 625 mg sCOD per g BD VS and 408 mg g−1 BD VS respectively. Due to the uplift of pH from 4 to 5.5 because of addition of ISR, the VFA composition was dominated mostly by butyric, acetic acids and propionic acid. Kinetics regarding rate of hydrolysis and acidification were calculated and reported. A significant synergistic effect was noticed in the acidification and hydrolysis, which were 1.76 and 1.35 fold higher than individual components (paper waste and food waste) of OFMSW, respectively and approximately 70% of biodegradable solid carbon solubilized into the liquid carbon within a short retention time of 78 h.

Landfill odors have created a major concern for the Chinese public. Based on the combination of a first order decay (FOD) model and a ground-level point source Gaussian dispersion model, the impacts from odors emitted from the 1955 landfills in China are evaluated in this paper. Our bottom-up approach uses basic data related to each landfill to achieve a more accurate and comprehensive understanding of impact of landfill odors. Results reveal that the average radius of impact of landfill odors in China is 796 m, while most landfills (46.85%) are within the range of 400-1000 m, in line with the results from previous studies. The total land area impacted by odors has reached 837,476 ha, accounting for 0.09% of China's land territory. Guangdong and Sichuan provinces have the largest land areas impacted by odors, while Tibet Autonomous Region and Tianjin Municipality have the smallest. According to the CALPUFF (California Puff) model and an analysis of social big data, the overall uncertainty of our calculation of the range of odor impacts is roughly -32.88% to 32.67%. This type of study is essential for gaining an accurate and detailed estimation of the affected human population and will prove valuable for addressing the current Not In My Back Yard (NIMBY) challenge in China.

Offensive odorant emissions from a food waste (FW) treatment plant that uses hydrothermal hydrolysis and aerobic fermentation technology were studied for 1 month through in situ monitoring and laboratory testing. Results showed that the emission flux (7000 μg kg−1FW h−1) of total volatile organic compounds and concentrations of most volatile organic compounds (VOCs) were highest at the discharge outlet of the hydrothermal hydrolysis reactor. Furthermore, VOC composition analysis showed that the concentrations of most hydrocarbons detected during the sorting/crushing process were higher than those in the aerobic fermentation process, but more oxygenated organic compounds and pinenes were released in the aerobic treatment process. The analysis of VOC temporal characteristics via t test indicated that even with various FW loads during the day and night, most VOC concentrations sampled in the storing room were not significantly different. However, great variances among most VOC concentrations were observed during the sorting/crushing process and at the hydrothermal hydrolysis reactor. The annoyance degrees of offensive gases were also determined via analysis of odor indices. The results suggested that sulfocompounds mainly dominated in terms of high odor activate values during the sorting/crushing process, and the fractional content of oxygenated organic compounds increased in the aerobic treatment processes.

This paper introduces the basic concept of flexible marshalling, summarizes the existing basic types of train marshalling transportation organization mode, contrasted to various types of applicable situation and advantages and disadvantages. Based on the analysis of the applicable conditions of flexible marshalling transportation organization mode in passenger flow and circuit, and analyzes the important factors which influence train flexible marshalling transportation organization from four aspects of passenger flow, facilities, operation efficiency and passenger service level. At last, some suggestions are put forward for train flexible marshalling transportation organization scheme design.

Food waste treatment plants (FWTPs) are usually associated with odorous nuisance and health risks, which are partially caused by volatile organic compound (VOC) emissions. This study investigated the VOC emissions from a selected full-scale FWTP in China. The feedstock used in this plant was mainly collected from local restaurants. For a year, the FWTP was closely monitored on specific days in each season. Four major indoor treatment units of the plant, including the storage room, sorting/crushing room, hydrothermal hydrolysis unit, and aerobic fermentation unit, were chosen as the monitoring locations. The highest mean concentration of total VOC emissions was observed in the aerobic fermentation unit at 21,748.2-31,283.3 μg/m3, followed by the hydrothermal hydrolysis unit at 10,798.1-23,144.4 μg/m3. The detected VOC families included biogenic compounds (oxygenated compounds, hydrocarbons, terpenes, and organosulfur compounds) and abiogenic compounds (aromatic hydrocarbons and halocarbons). Oxygenated compounds, particularly alcohols, were the most abundant compounds in all samples. With the use of odor index analysis and principal components analysis, the hydrothermal hydrolysis and aerobic fermentation units were clearly distinguished from the pre-treatment units, as characterized by their higher contributions to odorous nuisance. Methanthiol was the dominant odorant in the hydrothermal hydrolysis unit, whereas aldehyde was the dominant odorant in the aerobic fermentation unit. Terpenes, specifically limonene, had the highest level of propylene equivalent concentration during the monitoring periods. This concentration can contribute to the increase in the atmospheric reactivity and ozone formation potential in the surrounding air.

We demonstrate application of precise adiabatic vacuun calorimetry to observation of phase transition in the tripeptide l-alanyl-l-prolyl-glycine monohydrate (APG) from 6 to 320 K and report the standard thermodynamic properties of the tripeptide in the entire range. Thus, the heat capacity of APG was measured by adiabatic vacuun calorimetry in the above temperature range. The tripeptide exhibits a reversible first-order solid-to-solid phase transition characterized by strong thermal hysteresis. We report the standard thermodynamic characteristics of this transition and show that differential scanning calorimetry can reliably characterize the observed phase transition with

A large number of beacon nodes will be applied to the weighted centroid localization algorithm, but too much hardware facilities will affect the efficiency of the algorithm. Using the cosine theorem, On the basis of the original beacon nodes, add some virtual static beacon nodes to participate in orientation, It can reduce the hardware cost required for positioning. In addition, the math on and analysis of the localization algorithm, by derivative principle explaining the weight coefficient and RSSI ranging influence on localization algorithm. Simulation experiments show that the weighted centroid algorithm based on VSBN needed fewer beacon nodes, high positioning accuracy.

Increase in world population is usually followed by growing demand for food and increasingly higher requirements for the quality of food. The existing crops may require immediate improvement and optimization in order to adjust to market demands and the deteriorating environment. Genome editing breeding, a relatively advanced technology method that appeared in recent years, can accurately edit i.e. insert, delete or replace genes and directionally modify crops, by changing the plant's heredity and performance. Currently, some of the modern genome editing approaches has been applied rather widely in crop breeding e.g. zinc finger nuclease (ZFN), transcription activator-like effector nuclease (TALEN) and Clustered regularly interspaced short palindromic repeats/CRISPR associated protein (CRISPR/Cas). While reviewing the principles of the above genome editing technologies and their research progress in crop improvement, this paper will discuss the commercial application and future development of these technol...