A novel fluffy PLGA/HA composite scaffold for bone defect repair.

Treatment of bone defects remains crucial challenge for successful bone healing, which arouses great interests in designing and fabricating ideal biomaterials. In this regard, the present study focuses on developing a novel fluffy scaffold of poly Lactide-co-glycolide (PLGA) composites with hydroxyapatite (HA) scaffold used in bone defect repair in rabbits. This fluffy PLGA/HA composite scaffold was fabricated by using multi-electro-spinning combined with biomineralization technology. In vitro analysis of human bone marrow mesenchymal stem cells (BMSCs) seeded onto fluffy PLGA/HA composite scaffold showed their ability to adhere, proliferate and cell viability. Transplant of fluffy PLGA/HA composite scaffold in a rabbit model showed a significant increase in mineralized tissue production compared to conventional and fluffy PLGA/HA composite scaffold. These findings are promising for fluffy PLGA/HA composite scaffolds used in bone defects.

Sustained release silicon from 3D bioprinting scaffold using silk/gelatin inks to promote osteogenesis.

Repairing extensive bone defects that cannot self-heal has been a clinical challenge. The construction of scaffolds with osteogenic activity through tissue engineering can provide an effective strategy for bone regeneration. This study utilized gelatin, silk fibroin, and Si3N4 as scaffold materials to prepare silicon-functionalized biomacromolecules composite scaffolds using three-dimensional printing (3DP) technology. This system delivered positive outcomes when Si3N4 levels were 1 % (1SNS). The results showed that the scaffold had a porous reticular structure with a pore size of 600-700 µm. The Si3N4 nanoparticles were distributed uniformly in the scaffold. The scaffold could release Si ions for up to 28 days. In vitro experiments showed that the scaffold had good cytocompatibility, promoting the osteogenic differentiation of mesenchymal stem cells (MSCs). In vivo experiments on bone defects in rats showed that the 1SNS group facilitated bone regeneration. Therefore, the composite scaffold system showed potential for application in bone tissue engineering.

Identification of Fungal Pathogens to Control Postharvest Passion Fruit (Passiflora edulis) Decays and Multi-Omics Comparative Pathway Analysis Reveals Purple Is More Resistant to Pathogens than a Yellow Cultivar.

Production of passion fruit (Passiflora edulis) is restricted by postharvest decay, which limits the storage period. We isolated, identified, and characterized fungal pathogens causing decay in two passion fruit cultivars during two fruit seasons in China. Morphological characteristics and nucleotide sequences of ITS-rDNA regions identified eighteen isolates, which were pathogenic on yellow and purple fruit. Fusarium kyushuense, Fusarium concentricum, Colletotrichum truncatum, and Alternaria alternata were the most aggressive species. Visible inspections and comparative analysis of the disease incidences demonstrated that wounded and non-wounded yellow fruit were more susceptible to the pathogens than the purple fruit. Purple cultivar showed higher expression levels of defense-related genes through expression and metabolic profiling, as well as significantly higher levels of their biosynthesis pathways. We also found fungi with potential beneficial features for the quality of fruits. Our transcriptomic and metabolomics data provide a basis to identify potential targets to improve the pathogen resistance of the susceptible yellow cultivar. The identified fungi and affected features of the fruit of both cultivars provide important information for the control of pathogens in passion fruit industry and postharvest storage.

Strategies towards PM2.5 attainment for non-compliant cities in China: A case study.

The northern part of the Yangtze River Delta (YRD) region in China suffers from high concentrations of fine particular matter (PM2.5) during the past years yet received much less attention compared to the other parts of the YRD region. In this study, we integrated observational data, control policies and strategies, and air quality simulations to develop PM2.5 attainment demonstration by year 2030 for the city of Bengbu, which represents a typical non-compliant city in the northern YRD region. In 2018, the annual average PM2.5 concentration in Bengbu was 51.8 µg/m3, which was 48 % higher than the standard of 35 µg/m3 set by the National Ambient Air Quality Standards (NAAQS). Different future emission scenarios were developed for year 2025 as mid-term and year 2030 as long-term. Integrated meteorology and air quality modeling system together with monitoring data was applied to predict the air quality under the future emission scenarios. Results show that when a conservative emission reduction ratio of 40 % was assumed for surrounding regions, the annual average PM2.5 concentration in Bengbu could meet the target value by 2030, in which case emissions of SO2, NOx, PM2.5, VOCs, and NH3 need to be reduced by 70.6 %, 43.5 %, 47.2 %, 33.4 %, and 47.5 %, respectively. PM2.5 concentration in Bengbu is not only controlled by local emission reductions but also affected by emission reductions of surrounding regions as well as contribution from long-range transport. More attentions need to be paid to the control of VOCs emissions in the near future to avoid increase of ozone concentrations while reducing PM2.5. Our results provide scientific support for the local government to formulate future air pollution prevention and control strategies, sub-regional joint-control among surrounding cities, as well as trans-regional joint-control between the north China and the YRD region.

[Preparation and characterization of oriented scaffolds derived from cartilage extracellular matrix and silk fibroin].

OBJECTIVE: This study aims to prepare oriented scaffolds derived from a cartilage extracellular matrix (CECM) and silk fibroin (SF) and use to investigate their physicochemical property in cartilage tissue engineering. METHODS: Oriented SF-CECM scaffolds were prepared from 6% mixed slurry (CECM：SF=1：1) through modified temperature gradient-guided thermal-induced phase separation, followed by freeze drying. The SF-CECM scaffolds were evaluated by scanning electron microscopy (SEM) and histological staining analyses and determination of porosity, water absorption, and compressive elastic modulus of the materials. RESULTS: The SEM image showed that the SF-CECM scaffolds contained homogeneous reticular porous structures in the cross-section and vertical tubular structures in the longitudinal sections. Histological staining showed that cells were completely removed, and the hybrid scaffolds retained proteogly can and collagen. The composition of the scaffold was similar to that of natural cartilage. The porosity, water absorption rate, and vertical compressive elastic modulus of the scaffolds were 95.733%±1.010%, 94.309%±1.302%, and (65.40±4.09) kPa, respectively. CONCLUSIONS: The fabricated SF-CECM scaffolds exhibit satisfactory physicochemical and biomechanical properties and thus could be an ideal scaffold in cartilage tissue engineering.

[Development and characterization of oriented scaffolds derived from cartilage extracellular matrix].

OBJECTIVE: This study aimed to prepare oriented scaffolds derived from a cartilage extracellular matrix (CECM) and to investigate their physicochemical property and compatibility with adipose-derived stem cells (ADSCs). METHODS: A fresh porcine articular cartilage was cut into pieces. Cartilage nanofibers with diameters of 50-500 nm were collected through homogenization and centrifugation. These nanofibers were then decellularized by using Triton X-100 to produce 6% CECM. The oriented scaffolds derived from the nanoscale CECM were fabricated through unidirectional solidification and lyophilization. Afterward, these scaffolds were crosslinked. The physical and chemical performances and cell compatibility of CECM-oriented scaffolds were evaluated. RESULTS: The cross-sections of the scaffolds contained homogeneous reticular porous structures with nanofibers on the walls of the pores, and the longitudinal sections revealed vertical tubular structures. Hematoxylin-eosin staining revealed that the scaffolds were red without blue. Toluidine blue, safranin O, and Sirius red staining showed positive results. The porosity, water absorption rate, and vertical compressive elastic modulus of the scaffolds were 95.455%±0.910%, 95.889%±1.071%, and (40.208±5.097) kPa, respectively. CONCLUSIONS: The components of the oriented scaffolds derived from CECM are similar to those of native cartilage with favorable biocompatibility. The porous structures and sizes of the scaffolds are suitable for the adhesion, proliferation, and infiltration of ADSCs. The oriented scaffolds derived from CECM are relatively optimal for cartilage tissue engineering. 
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Chinese Cretaceous larva exposes a southern Californian living fossil (Insecta, Coleoptera, Eucnemidae).

Palaeoxenus sinensis Chang, Muona & Teräväinen sp. nov. (Coleoptera, Eucnemidae) is described on the basis of a Cretaceous larva found from the Yixian Formation in Huangbanjigou, Liaoning Province, China. The only previously known member of this clade is a southern Californian endemic, Dohrn's elegant eucnemid beetle (Palaeoxenus dohrni), a species that develops in conifers, especially the incense cedar (Calocedrus decurrens). The new find proves that the highly specialized main eucnemid lineages had evolved 123 Mya, before the main radiation of the angiosperms and probably as an adaptation to development in gymnosperms.

A flexible transparent gas barrier film employing the method of mixing ALD/MLD-grown Al2O3 and alucone layers.

Atomic layer deposition (ALD) has been widely reported as a novel method for thin film encapsulation (TFE) of organic light-emitting diodes and organic photovoltaic cells. Both organic and inorganic thin films can be deposited by ALD with a variety of precursors. In this work, the performances of Al2O3 thin films and Al2O3/alucone hybrid films have been investigated. The samples with a 50 nm Al2O3 inorganic layer deposited by ALD at a low temperature of 80°C showed higher surface roughness (0.503 ± 0.011 nm), higher water vapor transmission rate (WVTR) values (3.77 × 10(-4) g/m(2)/day), and lower transmittance values (61%) when compared with the Al2O3 (inorganic)/alucone (organic) hybrid structure under same conditions. Furthermore, a bending test upon single Al2O3 layers showed an increased WVTR of 1.59 × 10(-3) g/m(2)/day. However, the film with a 4 nm alucone organic layer inserted into the center displayed improved surface roughness, barrier performance, and transmittance. After the bending test, the hybrid film with 4 nm equally distributed alucone maintained better surface roughness (0.339 ± 0.014 nm) and barrier properties (9.94 × 10(-5) g/m(2)/day). This interesting phenomenon reveals that multilayer thin films consisting of inorganic layers and decentralized alucone organic components have the potential to be useful in TFE applications on flexible optical electronics.

Modeling neuron selectivity over simple midlevel features for image classification.

We now know that good mid-level features can greatly enhance the performance of image classification, but how to efficiently learn the image features is still an open question. In this paper, we present an efficient unsupervised midlevel feature learning approach (MidFea), which only involves simple operations, such as k-means clustering, convolution, pooling, vector quantization, and random projection. We show this simple feature can also achieve good performance in traditional classification task. To further boost the performance, we model the neuron selectivity (NS) principle by building an additional layer over the midlevel features prior to the classifier. The NS-layer learns category-specific neurons in a supervised manner with both bottom-up inference and top-down analysis, and thus supports fast inference for a query image. Through extensive experiments, we demonstrate that this higher level NS-layer notably improves the classification accuracy with our simple MidFea, achieving comparable performances for face recognition, gender classification, age estimation, and object categorization. In particular, our approach runs faster in inference by an order of magnitude than sparse coding-based feature learning methods. As a conclusion, we argue that not only do carefully learned features (MidFea) bring improved performance, but also a sophisticated mechanism (NS-layer) at higher level boosts the performance further.

Severe anemia and melena caused by pyeloduodenal fistula due to renal stone-associated squamous cell carcinoma.

Pyeloduodenal fistula is a rare condition and its association with malignancy is even rarer. Herein we report the case of a 66-year-old man who was admitted to the hospital with a three-month history of intermittent melena and a more than 20-year history of right-side renal stones. Computed tomography showed a heterogeneous right renal mass with a staghorn stone that had invaded the duodenum and caused an internal fistula. An upper gastrointestinal series showed pyeloduodenal fistula. The patient underwent an exploratory operation and a biopsy was taken at the peripelvic region. Pathological examination verified the existence of squamous cell carcinoma. To our knowledge, this is the first case of pyeloduodenal fistula associated with renal stones, squamous cell carcinoma and upper urinary tract calculus presenting on melena. We report on the features of this rare entity but also review and summarize the etiology, diagnosis and treatment options that can be extrapolated from the existing literature.

Xenoimplantation of an extracellular-matrix-derived, biphasic, cell-scaffold construct for repairing a large femoral-head high-load-bearing osteochondral defect in a canine model.

This study was aimed to develop an ECM-derived biphasic scaffold and to investigate its regeneration potential loaded with BM-MSCs in repair of large, high-load-bearing osteochondral defects of the canine femoral head. The scaffolds were fabricated using cartilage and bone ECM as a cartilage and bone layer, respectively. Osteochondral constructs were fabricated using induced BM-MSCs and the scaffold. Osteochondral defects (11 mm diameter × 10 mm depth) were created on femoral heads of canine and treated with the constructs. The repaired tissue was evaluated for gross morphology, radiography, histological, biomechanics at 3 and 6 months after implantation. Radiography revealed that femoral heads slightly collapsed at 3 months and severely collapsed at 6 months. Histology revealed that some defects in femoral heads were repaired, but with fibrous tissue or fibrocartilage, and femoral heads with different degrees of collapse. The bone volume fraction was lower for subchondral bone than normal femoral bone at 3 and 6 months. Rigidity was lower in repaired subchondral bone than normal femoral bone at 6 months. The ECM-derived, biphasic scaffold combined with induced BM-MSCs did not successfully repair large, high-load-bearing osteochondral defects of the canine femoral head. However, the experience can help improve the technique of scaffold fabrication and vascularization.

Mechanism of and relation between the sorption and desorption of nonylphenol on black carbon-inclusive sediment.

Correlation between the sorption and desorption of nonylphenol (NP) and binary linear regression were conducted to reveal the underlying mechanism of and relation between sorption domains and desorption sites in black carbon (BC)-amended sediment. The sorption and desorption data could be fitted well using dual-mode (R(2) = 0.971-0.996) and modified two-domain model (R(2) = 0.986-0.995), respectively, and there were good correlations between these two parts of parameters (R(2) = 0.884-0.939, P < 0.01). The NP percentage in desorbable fraction was almost equal to that of the partition fraction, suggesting the desorbed NP came from linear partition domain, whereas the resistant desorption NP was segregated in nonlinear adsorption sites, which were dominated by pores in BC-amended sediment. Our investigation refined theory about the relation between sorption domains and desorption sites in sediment and could be used to predict the release risk of NP using sorption data when BC is used for NP pollution control.

Preliminary investigation of a sensitive biomarker of organotin pollution in Chinese coastal aquatic environment and marine organisms.

In nine batches of sea bivalves collected from Chinese coastal cities during the year of 2000 to 2002, a special sample named Mya arenaria was found to have strong ability of butyltin accumulation compared with the other sampled bivalves in the corresponding batches. Tributyltin compound was the predominant pollutant with the detection rate high up to 100%. Special high levels of g Sn/g were detected in some Mya arenaria samples. The results obtained showed that Mya arenaria was potentially a biomarker to indicate organotin pollution in coastal aquatic environment.