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Technological comparison and system modelling of sewage sludge treatment are important in terms of sustainable development and climate change mitigation. Dewatering and drying are important processes for reducing volume for transportation and often a requirement for further sludge treatment. Inventory data on mass transfers and material and energy consumptions are therefore crucial in improving and understanding sludge management systems. Reviewing the scientific literature (2003–2021) revealed 55 and 21 datasets on dewatering and drying of sewage sludge, respectively. The scarcity of data did not allow for identifying detailed relationships between inputs and outputs for the technologies, but the reviewed data can serve as the first port of call when planning sludge management. The average total solid (TS) content obtained was statistically different for mechanical dewatering (MDW), deep dewatering, bio-drying (BDR) and thermal drying (TDR). Loss of volatile solids (VS) during dewatering is barely described, but a substantial VS loss was observed for TDR (8%) and BDR (27%). The use of chemical agents in MDW showed typical values of 5–15 g kg−1 TS. The use of energy is low for MDW (average of 0.12 and 0.26 kWh kg−1 TS for raw and digested sludges, respectively) but substantially higher for TDR (average of 3.8 kWh kg−1 TS). The justified inventory data for sludge dewatering and drying provide essential support to system modelling and technological comparison in future studies, but additional data from full-scale plants on energy consumption and the composition of removed water are strongly requested to improve the inventory.

System modelling of sewage sludge (SS) treatment attracts a growing interest for better comparison and optimisation of technologies. However, SS parameters need to be generalised to be used in holistic assessments, since scattered data may inhibit the development and interpretation of system models. A review of the literature on SS parameters relevant to modelling SS treatment systems revealed 208 datasets published in 162 publicly available scientific papers. We treated thickened and dewatered sludge in the same data analysis, but in some cases, this was an incorrect assumption. The compositional data showed significant variations, but most of the data subscribed to a lognormal distribution, albeit with varying levels of significance. On average, the thickened sludge contained 3.3 ± 1.7% total solid (TS), and the dewatered sludge contained 21.0 ± 6.7% TS. For the combined data, the average Ash content was 32.4 ± 11.8% of TS. Other characteristic parameters were the lower heating value (LHV) of 22.1 ± 2.1 MJ kg−1 volatile solid (VS) and the biochemical methane potential (BMP) of 0.25 ± 0.11 m3 CH4 kg−1 VS. Fertiliser-related elements were on average 53.3 ± 9.3% C in VS, 6.8 ± 2.2% N in VS, 6.7 ± 2.4% P in Ash and 1.7 ± 1.3% K in Ash. The data reviewed herein provide a good basis for assessing the generality of individual SS data and for selecting key parameters for modelling SS treatment systems. However, the review reveals a need for the better characterisation of SS in the future.

Landfills release significant odorous compounds from the working surface, and their emission rates are crucial for odor and health risk assessment. A total of 99 valid datasets of odor emissions from a landfill working surface were obtained from in situ monitoring for 9 months. Meteorological parameters (temperature, humidity, atmospheric pressure) and waste properties (contents of protein, lipid, carbohydrate, ash, and moisture) were used to construct artificial neural network (ANN) models for the emission rate prediction of typical compounds. The optimal structures and performance of the ANN models were determined by comparing and training with different structural configurations. The ANN models with genetic algorithm (GA) optimization show better performance than those without GA. With the data distribution of input parameters, the ranges of the emission rates of typical compounds were predicted by combining the established ANN models and the Monte Carlo approach. The sensitivity and uncertainty analyses revealed that temperature, atmospheric pressure, protein and lipid contents are parameters sensitive to emission rates, and meteorological parameters have significant impacts on the uncertainty. The established ANN models for the prediction of emission rates can provide scientific evidence and an approach to assess and control the odor and health risk in waste sectors.

Insect development requires genes to be expressed in strict spatiotemporal order. The dynamic regulation of genes involved in insect development is partly orchestrated by the histone acetylation-deacetylation via histone acetyltransferases (HATs) and histone deacetylases (HDACs). Although histone deacetylase 3 (HDAC3) is required for mice during early embryonic development, its functions in

Auxenochlorella pyrenoidosa is an efficient photosynthetic microalga with autotrophic growth and reproduction, which has the advantages of rich nutrition and high protein content. Target of rapamycin (TOR) is a conserved protein kinase in eukaryotes both structurally and functionally, but little is known about the TOR signalling in Auxenochlorella pyrenoidosa. Here, we found a conserved ApTOR protein in Auxenochlorella pyrenoidosa, and the key components of TOR complex 1 (TORC1) were present, while the components RICTOR and SIN1 of the TORC2 were absent in Auxenochlorella pyrenoidosa. Drug sensitivity experiments showed that AZD8055 could effectively inhibit the growth of Auxenochlorella pyrenoidosa, whereas rapamycin, Torin1 and KU0063794 had no obvious effect on the growth of Auxenochlorella pyrenoidosaa. Transcriptome data results indicated that Auxenochlorella pyrenoidosa TOR (ApTOR) regulates various intracellular metabolism and signaling pathways in Auxenochlorella pyrenoidosa. Most genes related to chloroplast development and photosynthesis were significantly down-regulated under ApTOR inhibition by AZD8055. In addition, ApTOR was involved in regulating protein synthesis and catabolism by multiple metabolic pathways in Auxenochlorella pyrenoidosa. Importantly, the inhibition of ApTOR by AZD8055 disrupted the normal carbon and nitrogen metabolism, protein and fatty acid metabolism, and TCA cycle of Auxenochlorella pyrenoidosa cells, thus inhibiting the growth of Auxenochlorella pyrenoidosa. These RNA-seq results indicated that ApTOR plays important roles in photosynthesis, intracellular metabolism and cell growth, and provided some insights into the function of ApTOR in Auxenochlorella pyrenoidosa.

In this paper, we give a complete classification of cotorsion pairs in [Formula: see text]-cluster categories of type [Formula: see text], denoted by [Formula: see text], via certain configurations of [Formula: see text]-diagonals, called Ptolemy diagrams. As applications, we classify [Formula: see text]-rigid subcategories of [Formula: see text], which gives Jacquet–Malo’s classification of [Formula: see text]-cluster tilting subcategories of [Formula: see text]. When [Formula: see text], this generalizes the work of Holm et al. [Ptolemy diagrams and torsion pairs in the cluster category of Dynkin type [Formula: see text], J. Algebraic Combin. 34(3) (2011) 507–523] for the classification of torsion pairs in cluster categories of type [Formula: see text].

The potential climate change impacts of the development in Chinese household waste management, with less landfilling, more incineration with energy recovery, and source-separated food waste treated in biorefineries, were assessed through a life cycle assessment. When the waste management system interacts with a fossil-based energy system, landfilling produces a load of 144 kg CO

The biological treatment of municipal sewage sludge, including anaerobic digestion and composting, was reviewed with the purpose of establishing inventory data to address all the inputs and outputs related to sludge treatment. We identified 193 scientific papers, resulting in 64 datasets on anaerobic digestion and 35 datasets on composting. For anaerobic digestion, biogas production varied significantly (up to a factor of four) depending on the sludge. A useful correlation was identified between the amount of methane produced and the degradation of volatile solids. According to statistical tests, no significant differences were found in biogas production for mesophilic and thermophilic digesters. In addition, methane content varied significantly, and very few data were available for digestate composition or for energy consumption and recovery. For composting, accurate estimates relating to the degradation of sewage sludge could not be made, since organic bulking materials were part of the final composted product. Data on emissions to air are currently scarce, which points to the need for more published information. The inventory data evaluated herein are useful in the feasibility assessment of the biological treatment of sewage sludge, for comparing technologies, for example in LCA studies and as a basis for evaluating the performance of a specific biological sludge treatment plant. However, a great deal of the reviewed data originated from laboratory and pilot-scale studies, and so there is a need for more complete datasets on the performance of full-scale technologies, in order to establish full inventories and identify differences in technologies and operational conditions.

The thermal treatment of sewage sludge has gained much interest in recent years, as exemplified by the 269 papers found in the scientific literature for the period 2010-2021. We identified 140 datasets in 57 papers presenting inventory data related to mass flows, energy and emissions for the incineration, gasification and pyrolysis of sewage sludge. Sewage sludge incineration (excess oxygen, 850-950 ℃) is an established technology; however, data on flue gas cleaning and air emissions are scarce. The recovery of energy is close to the amount of energy used for incinerating dried sludge (0.2 kWh/kg TS), while dewatered sludge incineration uses more energy (1-2 kWh/kg TS) than what can be recovered. Sewage sludge gasification (limited oxygen, 650-950 ℃) is an experimental technology with four outputs (kg/kg sludge TS): char 0.43, tar 0.02, fly ash 0.06 and syngas 0.53. The data vary significantly in this regard, suggesting than many factors affect the performance of the gasification process. Sewage sludge pyrolysis (no oxygen, 400-800 ℃) is an experimental technology with five outputs (kg/kg sludge TS): char 0.53, tar 0.21, water 0.05, fly ash set to zero and syngas 0.21. The values are somewhat different for digested sludge. Energy consumption for the pyrolysis of sewage sludge cannot be estimated from the literature. The current literature provides useful data on the main flows of thermal technologies, although large variations are in evidence. However, data are limited on energy consumption and recovery in general, and they are scarce on direct emissions to the air from incineration.

Most anti-collusion audio fingerprinting schemes are aiming at finding colluders from the illegal redistributed audio copies. However, the loss caused by the redistributed versions is inevitable. In this letter, a novel fingerprinting scheme is proposed to eliminate the motivation of collusion attack. The audio signal is transformed to the frequency domain by the Fourier transform, and the coefficients in frequency domain are reversed in different degrees according to the fingerprint sequence. Different from other fingerprinting schemes, the coefficients of the host media are excessively modified by the proposed method in order to reduce the quality of the colluded version significantly, but the imperceptibility is well preserved. Experiments show that the colluded audio cannot be reused because of the poor quality. In addition, the proposed method can also resist other common attacks. Various kinds of copyright risks and losses caused by the illegal redistribution are effectively avoided, which is significant for protecting the copyright of audio.

Let G be a finite group and let χ ∈ Irr ( G ) be an irreducible complex character of G. We show under certain conditions that all pairs ( H , ξ ) , consisting of a subgroup H of G and some primitive character ξ ∈ Irr ( H ) inducing χ, are “equivalent” by using inductors of character triples due to Dade and Isaacs. As applications of this result, we strengthen many known theorems, which state that under the same conditions all primitive characters inducing χ from subgroups of G have equal degrees.

Odor pollution from treatment facilities and municipal solid waste (MSW) has caused wide public concern. Odorous compounds released from these facilities possess complex composition. Therefore, identifying typical odorous compounds and using their release rates to estimate those of other compounds may simplify the monitoring and evaluation of odor pollution. This study investigates the correlations of the release data of odorous compounds from a statistical perspective. For 12 months, we conducted in site monitoring in an MSW transfer station once each month to obtain 96 emission samples, and over 100 odorous compounds were quantified for each sample. Oxygenated compounds had considerable high release rates throughout the period, and ethanol was the dominant compound. Ethanol, dimethyl disulfide and methyl mercaptan were the top key compounds that contributed to the odor activity value. Correlation analyses within and across the categories showed that only a few compounds in saturated hydrocarbons and aromatic compounds had strong correlations with release rate. The coefficient of correlation between ethylbenzene and 19 other compounds, which covered only 25% of all the identified compounds in this study, was >0.5. These results show that representative compounds cannot be used in the calculation of release rate during the transfer stage.

The rapid development of e-commerce has resulted in a large amount of express delivery package waste (EDPW). The optimisation of EDPW systems is important to achieve low-carbon development. To quantify the impact and C-footprint reduction potential, a comprehensive life cycle assessment enhanced by parameterisation and global sensitivity analysis was conducted on Chinese EDPW systems managing fractions of cardboard, paper and envelope, foamed plastic, soft plastic and woven bag. Material flow analysis reveals that 65% of the EDPW is recycled and cardboard is the dominant contributor. The environmental impacts from EDPW to most impact categories are marginal, but the loads to global warming potentials and human toxicity are significant, mainly attributed to the energy and material consumption during package production. From C-footprint perspective, managing 1,000kg of EDPW would generate a load of 834.88 kg CO2-eq from raw material production and a saving of -524.55 kg CO2-eq from material and energy recovery. Paper and cardboard incineration can achieve carbon reduction with biogenic-CO2 emissions, while plastic incineration releases significant fossil-CO2 that counteracts the savings from energy recovery. Global sensitivity analysis identified proportion of incineration, heat and electricity recovery ratios in incinerators and recycling ratio of cardboard as the major contributors to result uncertainty. Optimising these parameters can achieve a carbon reduction of 177.86 kg CO2-eq per 1,000kg of EDPW. This paper provides a comprehensive view of the environmental impacts of EDPW in waste management system and novel insights into further optimisation and development of the system from a low-carbon perspective.

Volatile organic compounds (VOCs) emitted from the working surface of landfills have received increasing attention due to the potential risks to human health. Quantifying the emission rates of risky VOCs is important to their health risk assessment but is also challenging because of their high variation and complicated relationship between the emission rates and various influencing factors. In this study, a continuous nine-month sampling of VOCs was conducted on a landfill working surface to identify dominant VOCs that are risky to human health and to construct artificial neural network (ANN) models for their emission rates by involving 105 datasets. Among the 63 detected VOCs, ethanol presented the highest emission rate (885.28 ± 1398.10 μg·m

Artificial neural networks (ANNs) have recently attracted significant attention in environmental areas because of their great self-learning capability and good accuracy in mapping complex nonlinear relationships. These properties of ANNs benefit their application in solving different solid waste-related issues. However, the configurations, including ANN framework, algorithm, data set partition, input parameters, hidden layer, and performance evaluation, vary and have not reached a consensus among relevant studies. To address the current state of the art of ANN application in the solid waste field and identify the commonalities of ANNs, this critical review was conducted by focusing on a modeling perspective and using 177 relevant papers published over the last decade (2010-2020). We classified the reviewed studies into four categories in terms of research scales. ANNs were found to be applied widely in waste generation and technological parameter prediction and proven effective in solving meso-microscale and microscale issues, including waste conversion, emissions, and microbial and dynamic processes. Given the difficulty of data collection in many solid waste-related issues, most studies included a data size of 101-150. For mathematical optimization, dividing the data into training-validation-test sets is preferable, and the training set is supposed to account for ~70%. A single hidden layer is usually sufficient, and the optimal numbers of hidden layer nodes most likely range from 4 to 20. This review is supposed to contribute basic and comprehensive knowledge to the researchers in general waste management and specialized ANN study on solid waste-related issues.

We define weakly quasi-primitive characters of solvable groups as a generalization of quasi-primitive characters, and present three main results about the zeros and the values for these characters, which in turn strengthen the corresponding theorems for quasi-primitive characters due to G. Navarro and T. Wilde.

In this paper, we give a complete classification of cotorsion pairs in a cluster category C of type A ∞ ∞ via certain configurations of arcs, called τ-compact Ptolemy diagrams, in an infinite strip with marked points. As applications, we classify t-structures and functorially finite rigid subcategories in C , respectively. We also deduce Liu–Paquette's classification of cluster tilting subcategories of C and Ng's classification of torsion pairs in the cluster category of type A ∞ .

Odour pollution from municipal solid waste is a public nuisance and a threat to the health of residents nearby. Attention and understanding towards odour emissions from waste collection vehicles are insufficient, and dispersion simulation using conventional modelling tools cannot be applied because their special operational characteristics do not conform to either point or linear sources. This study proposes a new dispersion simulation method for mobile point sources with ModOdor, which is a 3D numerical model previously developed by the authors. The 12-month monitoring data show that ethanol, dimethyl disulphide and methylene chloride were identified as typical odorous compounds released from waste collection vehicles. Ethanol dispersion was simulated as a mobile point source for low- and high-speed modes by synchronously changing temporal and spatial grids in high precision. Results revealed the variations in concentration distribution, dispersion distance and impact duration. In general, a diameter of area with odour activity value higher than 0.1 was identified at approximately 30–50 m after stable dispersion. The impact duration varied from approximately 20 s to 40 s along with the tested source intensities, wind directions and speeds with a benchmark of 10 μg·m−3. This study verified the applicability of the proposed method for the dispersion simulation of mobile point sources and provided useful approach and information for evaluating the odour pollution from waste collection vehicles.

The environmental impact potentials of producing bioethanol from corn stover were systematically assessed by life cycle assessment using datasets reported in the literature. The 15% best datasets with respect to global warming potential for seven different technological configurations were extracted from a published database reviewing 474 publications on converting corn stover to bioethanol. A total of 10 impact categories were evaluated. The impacts included both environmental loads and savings, and generally ranged from −0.1 to 0.1 person-equivalent per ton of dry corn stover for most non-toxic impacts and −0.2 to 0.5 person-equivalent for toxic impacts. Fossil fuel substitution with bioethanol provided savings in most impact categories, and so did the energy recovered from the residues, while enzyme production was a significant load. The treatment and discharge of effluent from the liquid residues may constitute a significant load to the environment. Based on the cumulative probabilities of overall environmental performance together with the bioethanol amount produced, the prioritisation of technologies for further development should be as follows: steam explosion (S4) and ammonia-based (S6) technologies as the highest priorities with approximately 100% and 40% probabilities to have savings in non-toxic and toxic impacts, respectively; acid (S1), alkaline (S2) and fungi (S7) technologies as medium priorities and solvent-based (S3) and liquid hot water (S5) technologies have the lowest priorities. We suggest the integration of life cycle assessment modelling to the research and development of biofuel production from biomass waste to ensure that the technologies being developed for full-scale applications are sustainable.

Treatment facilities dealing with municipal solid waste (MSW) are typical pollution sources of urban odor nuisance which threatens public health and environmental safety. Dispersion simulation with specialized models is an important approach for simulating the concentration distribution and estimating the transport distances of the released odorous compounds. Given that the temporal and spatial distribution are affected by many factors with different variations and functions. This study investigated the influence of key parameters on the dispersion of odor compounds on the basis of a numerical atmospheric dispersion model. The sensitivity analysis was applied to quantitatively identify their influence on the concentration distributions and transport distances. The results reveal that source intensity is a sensitive parameter in the whole domain under the specified dispersion conditions, with the sensitivity ratios around 1 to concentrations and of 1.5–2.5 to transport distances. Wind speed possesses higher sensitivity ratios at the upwind direction than the downwind direction. Horizontal diffusion coefficient is sensitive to concentrations only in the area of a typical radius of 500 m from the source. Degradation reaction constant and wet deposition are not sensitive in either concentration distribution or transport distances. The most sensitive parameters present respective importance to the transport distances when different olfactory thresholds of compounds are applied to determine the protection area of odor pollution. This study thus provides important information to the application of dispersion models and the data collection of the most sensitive parameters in odor pollution evaluation and management.

Human umbilical cord blood-derived mesenchymal stem cells (hUC-MSCs) have been widely used in tissue engineering. The aim of this study is to evaluate the ability of poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) scaffolds coated with polyhydroxyalkanoate binding protein fused with arginyl-glycyl-aspartic acid (PhaP-RGD) to promote the proliferation and chondrogenic differentiation of hUC-MSCs seeded on them. The PhaP-RGD fusion protein was expressed by Escherichia coli. PHBHHx films were coated with PhaP-RGD fusion protein and the physiochemical properties were examined. hUC-MSCs were seeded on PHBHHx films with or without PhaP-RGD precoating and tested for changes in morphology, viability, and chondrogenic differentiation. We found that PhaP-RGD-coated PHBHHx films had similar surface morphology to uncoated PHBHHx. The water contact angle of the coated PHBHHx surface was lower than that of the uncoated surface (10.63° vs. 98.69°). At 7 and 14 days after seeding, the PhaP-RGD-coated PHBHHx group showed greater numbers of viable cells compared to the uncoated PHBHHx group. The expression levels of aggrecan and collagen II were enhanced in the PhaP-RGD-coated PHBHHx group relative to the uncoated PHBHHx group. Histological analysis using toluidine blue staining showed elevated formation of proteoglycan producing chondrocytes in the PhaP-RGD-coated PHBHHx group. Additionally, the synthesis of proteoglycan and collagen was significantly enhanced within the PhaP-RGD constructs. Taken together, PhaP-RGD coating promotes the proliferation and chondrogenic differentiation of hUC-MSCs seeded on PHBHHx films. PhaP-RGD-coated PHBHHx may be a useful scaffold for cartilage tissue engineering.

We introduce the notion of Fitting characters for arbitrary finite groups, and prove that under some conditions the product of these characters is irreducible and the unique factorization of this form also holds. Moreover, we show that any nonlinear quasi-primitive character of solvable groups can be uniquely factored (up to multiplication by linear characters) as the product of certain Fitting characters on some extension groups.

Let [Formula: see text] be a maximal subgroup of an [Formula: see text]-group [Formula: see text] with odd index and let [Formula: see text] be primitive. Lewis proved in this situation that [Formula: see text] divides [Formula: see text], and Isaacs and Wilde further refined this result by showing that either [Formula: see text] or [Formula: see text]. In this paper, we present an independent and simpler proof for these remarkable results and thereby obtain more detailed information regarding the structure of the group [Formula: see text] and the primitive character [Formula: see text]. In particular, [Formula: see text] is strongly irreducible in the sense of Brauer.

Let [Formula: see text] be a quasi-primitive character with odd degree, and suppose that [Formula: see text] is a [Formula: see text]-solvable group. Wilde associated to [Formula: see text] a unique conjugacy class of subgroups [Formula: see text] satisfying [Formula: see text]. We construct in this situation a sequence of character pairs [Formula: see text], where [Formula: see text] is quasi-primitive and each [Formula: see text] is uniquely determined up to conjugacy in [Formula: see text], such that [Formula: see text] and [Formula: see text]. Furthermore, we have [Formula: see text] for each [Formula: see text], and in particular [Formula: see text]. We also prove that the subgroups [Formula: see text] and [Formula: see text] are conjugate in [Formula: see text], and thus present a new description for Wilde’s result.

We give a complete classification of (co)torsion pairs in finite $2$-Calabi-Yau triangulated categories with maximal rigid objects which are not cluster tilting. These finite $2$-Calabi-Yau triangulated categories are divided into two main classes: one denoted by $\mathcal{A}_{n,t}$ called of type $A$, and the other denoted by $D_{n,t}$ called of type $D$. By using the geometric model of cluster categories of type $A, $ or type $D$, we give a geometric description of (co)torsion pairs in $\mathcal{A}_{n,t}$ or $D_{n,t}$ respectively, via defining the periodic Ptolemy diagrams. This allows to count the number of (co)torsion pairs in these categories. Finally, we determine the hearts of (co)torsion pairs in all finite $2$-Calabi-Yau triangulated categories with maximal rigid objects which are not cluster tilting via quivers and relations., 25pages

Current study we purified a polysaccharide (BRP) from Boschniakia rossica and the antitumor effects of BRP alone or combined with 5-Fluorouracil (5-FU) was examined in S180 tumor bearing mice by intragastric administration. The high performance size-exclusion chromatography (HPGEC) analysis showed that BRP was a homogeneous polysaccharide and had a molecular weight of 2.2 × 10(4) Da. Total carbohydrate content in BRP was determined to be 96.9%, without the presence of protein and nucleic acid. BRP alone or combined with 5-FU could significantly inhibit Sarcoma-180 (S180) tumor growth and increase the spleen index in a dose-dependent manner. Meanwhile a synergistic effect was observed in boosting various immunity functions when the tumor bearing mice receiving BRP plus 5-FU administration, such as stimulating lymphocytes proliferation, increasing NK cell cytotoxicity, enhancing serum interleukin-2 (IL-2) and interferon-gamma (TNF-γ) secretion, as well as augmenting CD4+ and CD8+ spleen T lymphocytes subsets. The results showed that BRP combined with 5-FU presented synergistic effects on antitumor activity in tumor bearing mice. In conclusion, the combination of BRP may boost the suppressed immunity in tumor bearing mice subject to 5-FU chemotherapy, and could serve as a new, promising approach for cancer treatment.

To deepen the understanding of chronic subdural hematoma and to seek the effective treatment for chronic subdural hematoma (CSDH).We retrospectively reviewed a series of 17 consecutive patients with CSDH, who received the treatment of bone flap craniotomy. To explore the surgical indications for CSDH, the data of imaging appearance, intraoperative findings and postoperative complications were analyzed.Among the patients, 13 were septated CSDH, with the characteristic imaging features such as anti-"3" impression in the inner edge of the hematoma and fibrous strap structure in the hematoma. Four patients were organized CSDH, with strong signals of T1 and T2 as well as hypointense netlike structure within the hematoma cavity while low signal on MRI in the thickened inner membrane. Burr hole trepanation was performed, but no improvement were achieved, whereas the bone flap craniotomy removed the hematoma completely without serious surgical complication except 1 case.Based on the preoperative imaging data, flap bone craniotomy seems to be the first choice for treatment of CSDH.

To study the hydrophilicity and the cell biocompatibility of the poly(3-hydroxybutyrate-co- 3-hydroxyvalerate) (PHBV) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) coated with a fusion protein polyhydroxyalkanoates granule binding protein (PhaP) fused with Arg-Gly-Asp (RGD) peptide (PhaP-RGD).PHBV and PHBHHx films were fabricated by solvent evaporation. Scanning electronic microscope (SEM) was used to study the morphology of the films. PhaP-RGD fusion proteins were expressed and purified by the technology of protein engineering; PHBV and PHBHHx films were immersed in the PhaP-RGD with an amount of 3.5 mg/mL protein/per sample respectively. The hydrophilicity of the surface were detected by the contact angle measurements. Septal cartilage cells obtained from human septal cartilage were cultured in vitro. The 2nd passage chondrocytes were incubated on PHBV unmodified with PhaP-RGD in group A1, PHBV modified with PhaP-RGD in group A2, PHBHHx unmodified with PhaP-RGD in group Bl, PHBHHx modified with PhaP-RGD in group B2, and on the cell culture plates in group C. After cultured for 3 days, the proliferation of cells was detected by the DAPI staining; the proliferation viability of cells was detected by the MTT assay after cultured for 3 and 7 days; after cultured for 7 days, the adhesion and morphology of the cells on the surface of the biomaterial films were observed by SEM and the matrix of the cells was detected through the toluidine blue staining.SEM observation showed that PHBV and PHBHHx films had porous structures. The contact angle of the surface of the PHBV and PHBHHx films modified with PhaP-RGD fusion proteins were significantly reduced when compared with the films unmodified with PhaP-RGD fusion proteins (P0.05). Chondrocytes of human nasal septal cartilage incubated on the films could grow in all groups. After 3 days of cultivation in vitro, the cell proliferation and viability of group B2 were the strongest among all groups (P0.05); the cell proliferation after cultured for 7 days was significantly stronger than that after cultured for 3 days in groups A1, A2, B1, and B2 (P0.05); and the cell proliferation was significantly stronger in groups B1 and B2 than groups A1, A2 and C, in group B2 than group B1, and in group A1 than group A2 (P0.05). The results of toluidine blue staining showed that blue metachromasia matrixes were observed in groups A1, A2, B1, and B2; group A1 and group A2 had similar staining degree, and the staining of group B2 was deeper than that of group B1. The adhesion of cells in all groups was good through SEM observation; and the connection of cells formed and stretched into the pores of the materials.The biomaterial films of PHBHHx modified with PhaP-RGD fusion protein can promote its biocompatibility with chondrocytes.

Human umbilical cord blood-derived mesenchymal stem cells (hUC-MSCs) have been widely used in tissue engineering. The aim of this study is to evaluate the ability of poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) scaffolds coated with polyhydroxyalkanoate binding protein fused with arginyl-glycyl-aspartic acid (PhaP-RGD) to promote the proliferation and chondrogenic differentiation of hUC-MSCs seeded on them. The PhaP-RGD fusion protein was expressed by Escherichia coli. PHBHHx films were coated with PhaP-RGD fusion protein and the physiochemical properties were examined. hUC-MSCs were seeded on PHBHHx films with or without PhaP-RGD precoating and tested for changes in morphology, viability, and chondrogenic differentiation. We found that PhaP-RGD-coated PHBHHx films had similar surface morphology to uncoated PHBHHx. The water contact angle of the coated PHBHHx surface was lower than that of the uncoated surface (10.63° vs. 98.69°). At 7 and 14 days after seeding, the PhaP-RGD-coated PHBHHx group showed greater numbers of viable cells compared to the uncoated PHBHHx group. The expression levels of aggrecan and collagen II were enhanced in the PhaP-RGD-coated PHBHHx group relative to the uncoated PHBHHx group. Histological analysis using toluidine blue staining showed elevated formation of proteoglycan producing chondrocytes in the PhaP-RGD-coated PHBHHx group. Additionally, the synthesis of proteoglycan and collagen was significantly enhanced within the PhaP-RGD constructs. Taken together, PhaP-RGD coating promotes the proliferation and chondrogenic differentiation of hUC-MSCs seeded on PHBHHx films. PhaP-RGD-coated PHBHHx may be a useful scaffold for cartilage tissue engineering.

Development and selection of an ideal scaffold is of importance for tissue engineering. Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) is a biocompatible bioresorbable copolymer that belongs to the polyhydroxyalkanoate family. Because of its good biocompatibility, PHBHHx has been widely used as a cell scaffold for tissue engineering. This review focuses on the utilization of PHBHHx-based scaffolds in tissue engineering. Advances in the preparation, modification, and application of PHBHHx scaffolds are discussed.

SRY-related high-mobility-group box 9 (Sox9) gene is a cartilage-specific transcription factor that plays essential roles in chondrocyte differentiation and cartilage formation. The aim of this study was to investigate the feasibility of genetic delivery of Sox9 to enhance chondrogenic differentiation of human umbilical cord blood-derived mesenchymal stem cells (hUC-MSCs). After they were isolated from human umbilical cord blood within 24 h after delivery of neonates, hUC-MSCs were untreated or transfected with a human Sox9-expressing plasmid or an empty vector. The cells were assessed for morphology and chondrogenic differentiation. The isolated cells with a fibroblast-like morphology in monolayer culture were positive for the MSC markers CD44, CD105, CD73, and CD90, but negative for the differentiation markers CD34, CD45, CD19, CD14, or major histocompatibility complex class II. Sox9 overexpression induced accumulation of sulfated proteoglycans, without altering the cellular morphology. Immunocytochemistry demonstrated that genetic delivery of Sox9 markedly enhanced the expression of aggrecan and type II collagen in hUC-MSCs compared with empty vector-transfected counterparts. Reverse transcription-polymerase chain reaction analysis further confirmed the elevation of aggrecan and type II collagen at the mRNA level in Sox9-transfected cells. Taken together, short-term Sox9 overexpression facilitates chondrogenesis of hUC-MSCs and may thus have potential implications in cartilage tissue engineering. publishedVersion

Jianmin Liang,1 Juan Hu,1 Huimin Chang,2 Ying Gao,1 Huanan Luo,1 Zhenghui Wang,1 Guoxi Zheng,1 Fang Chen,1 Ting Wang,1 Yeye Yang,1 Xiaohui Kou,1 Min Xu1 1Department of Otolaryngology-Head and Neck Surgery, The Second Hospital, Xi’an Jiaotong University, 2Department of Otolaryngology-Head and Neck Surgery, Affiliated Hospital of Xi’an Medical University, Xi’an, People’s Republic of China Abstract: The aim of this study is to report our experience in the diagnosis and treatment of tracheobronchial foreign bodies (TFBs). We retrospectively reviewed medical records of 2,000 TFB patients (1,260 males and 740 females) who were treated between January 2010 and December 2013. Chest radiography and computed tomography were performed to diagnose TFBs. The location and type of foreign bodies (FBs), anesthesia methods, and treatment outcomes and complications were analyzed. Overall, 72.5% of our patients with TFB were aged between 1years and 3years. Plant-based FBs are the most common FB type, accounting for 91.5%. Almost 52.1% of the FBs were encountered in the right bronchus. The coincidence rate for computed tomography-based three-dimensional reconstruction was significantly greater than that for chest X-ray examination (98.7% vs 82.0%, P