Chromosome-scale Genome assembly of the critically endangered White-eared Night-Heron (Gorsachius magnificus).

The White-eared Night-Heron (Gorsachius magnificus, G. magnificus) is a critically endangered heron that is very poorly known and only found in southern China and northern Vietnam, with an estimated population of 250 to 999 mature individuals. However, the lack of a reference genome has hindered the implementation of conservation management efforts. In this study, we present the first high-quality chromosome-scale reference genome, which was assembled by integrating PacBio long-reads sequencing, Illumina paired-end sequencing, and Hi-C technology. The genome has a total length of 1.176 Gb, with a scaffold N50 of 84.77 Mb and a contig N50 of 18.46 Mb. Utilizing Hi-C data, we anchored 99.89% of the scaffold sequences onto 29 pairs of chromosomes. Additionally, we identified 18,062 protein-coding genes in the genome, with 95.00% of which were functionally annotated. Notably, BUSCO assessment confirmed the presence of 97.2% of highly conserved Aves genes within the genome. This chromosome-level genome assembly and annotation will be valuable for future investigating the G. magnificus's evolutionary adaptation and conservation.

Subspecies Taxonomy and Inter-Population Divergences of the Critically Endangered Yellow-Breasted Bunting: Evidence from Song Variations.

The critically endangered Yellow-breasted Bunting has undergone population collapse globally because of illegal hunting and habitat deterioration. It was listed as critically endangered (CR) by the International Union for Conservation of Nature (IUCN) in 2017 and designated a Class I (highest level) national conservation bird species in China in 2021. Birdsong in the breeding season is the main communicative signal under sexual selection, and song variations have long been considered critical evidence of divergence among subspecies or populations. We compared the songs of 89 males from 18 populations to test subspecies taxonomy. We found that songs of the Yellow-breasted Bunting Emberiza aureola are subspecies specific and that three subspecies can be clearly discriminated by song divergences. Moreover, an analysis of multiple vocal traits supports the claim that insulana is distinct from aureola and ornata. Finally, at the geographic population level, populations can be clearly classified in accordance with the three subspecies, although the aureola population in Xinjiang, China is differentiated from other populations of the same subspecies. The results of this study demonstrate that all populations and subspecies are unique and should be protected to maintain intraspecies song diversity. In addition, several specific populations, such as insulana populations in Japan and the Xinjiang, China population of aureola, need to be paid special attention to prevent the extinction of unique or local taxa.

A review on biodegradable biliary stents: materials and future trends.

Biliary stricture is defined as the reduction and narrowing of the bile duct lumen, which can be caused by many factors such as cancer and inflammation. Biliary stent placement can effectively alleviate benign and malignant biliary strictures. However, the commonly used plastic or metallic biliary stents are far from ideal and do not satisfy all clinical requirements，although several types of biodegradable biliary stents have been developed and used clinically. In this review, we summarized current development status of biodegradable stents with the emphasis on the stent materials. We also presented the future development trends based on the published literature.

Evaluating tissue-engineered repair material for pelvic floor dysfunction: a comparison of in vivo response to meshes implanted in rats.

INTRODUCTION AND HYPOTHESIS: Achieving better anatomic restoration and decreasing the associated complications are necessary for material repair of pelvic floor dysfunction (PFD). This study was aimed to investigate host response to tissue-engineered repair material (TERM) in rat models by comparing different materials and study the changes in biomechanical properties over time. METHODS: TERM was constructed by seeding adipose-derived stem cells (ADSCs) on electrospun poly(L-lactide)-trimethylene carbonate-glycolide (PLTG) terpolymers. The TERM, PLTG, porcine small intestine submucosa mesh (SIS), and polypropylene (PP) (n = 6 / group per time point) were implanted in rats for 7, 30, 60, and 90 days. Hematoxylin-eosin and Masson's trichrome staining were used to assess the host response, and mechanical testing was used to evaluate the changes in biomechanical properties. RESULTS: In vivo imaging showed that the ADSCs were confined to the abdominal wall and did not migrate to other organs or tissues. The TERM was encapsulated by a thicker layer of connective tissue and was associated with less reduced inflammatory scores compared with PLTG and PP over time. The vascularization of the TERM was greater than that with PP and PLTG over time (p < 0.05) and was greater than that with SIS on day 90. The ultimate tensile strain and Young's modulus of the PP group showed the greatest increases, and the TERM group followed on day 90. CONCLUSIONS: This TERM achieved better host integration in rat models and better biomechanical properties, and it may be an alternative material for PFD.

A Novel Stereocomplex Poly(lactic acid) with Shish-Kebab Crystals and Bionic Surface Structures as Bioimplant Materials for Tissue Engineering Applications.

The development of green material possessing with great mechanical properties and biocompatibility has become a primary goal for high-performance biological material applications. Herein, the oriented shish-kebab crystals of stereocomplex poly(lactic acid) (SC-PLA) are first reported to be successfully fabricated through a feasible solid-state drawing (SSD) process to simultaneously enhance the mechanical performance and biocompatibility. The resultant biomaterial exhibits a tensile strength of 373 MPa and elongation about 9%, with elastic modulus about 8.1 GPa. Such an outstanding toughening effect is due to an amalgamation of enhanced crystallinity of epitaxial secondary growth lamellae and orientation degree of the fibrous backbone of the SC-PLA samples, both gradually increasing with the draw ratio of SSD increasing. Uniquely distinguished from the typical biomedical polymer with the smooth surface structure, the as-obtained SC-PLA samples possess a surface morphology of parallel microgrooves within ridge structures, attributing to the highly oriented fibrous backbone structure complemented with regularly arranged epitaxial lamellas. This unique trait well represents the human vascular endothelial microstructure that is desirable for cell adhesion-growth to extend its proliferation, differentiation, and activity on the surface of SC-PLA.

Improving Mechanical Properties and Biocompatibilities by Highly Oriented Long Chain Branching Poly(lactic acid) with Bionic Surface Structures.

Exploiting the solid-state drawing (SSD) process toward polymer materials for medical implant devices is of significance to simultaneously improve the mechanical property and biocompatibility. Herein, for the first time, the bionic implants with a microvalley surface of oriented long chain branching PLA (b-PLA) was fabricated by a feasible SSD process. The as-obtained b-PLAs could not only show a high tensile strength (278.1 MPa) and modulus (4.32 GPa) but also bear a superior protein adsorption as high as 622 ng/cm2. Such exceptional mechanical properties and biocompatibility could be ascribed to the SSD process-induced highly orientation degree and the morphology of parallel grooves within ridges structures, resulting in the greatly enhanced crystallinity and surface hydrophobicity as well as a biocompatible vascular endothelial microstructure for cell to adhesion and growth and thus an improved proliferation, differentiation, and activity of osteoblasts with spindle-shaped and spread morphology on surface of the b-PLAs. These findings may pave the way for designing the novel biomaterials for vascular stent or tissue engineering devices by the SSD process.

Dielectric Enhancement of Atomic Layer-Deposited Al2O3/ZrO2/Al2O3 MIM Capacitors by Microwave Annealing.

For metal-insulator-metal (MIM) capacitors applicated in the fields of RF, DRAM, and analog/mixed-signal integrated circuits, a high capacitance density is imperative with the downscaling of the device feature size. In this work, the microwave annealing technique is investigated to enhance the dielectric characteristics of Al2O3/ZrO2/Al2O3 based MIM capacitors. The results show that the permittivity of ZrO2 is increased to 41.9 (~ 40% enhanced) with a microwave annealing at 1400 W for 5 min. The substrate temperature is lower than 400 °C, which is compatible with the back end of line process. The leakage current densities are 1.23 × 10-8 and 1.36 × 10-8 A/cm2 for as-deposited sample and 1400 W sample, respectively, indicating that the leakage property is not deteriorated. The conduction mechanism is confirmed as field-assisted tunneling.

High-Performance On-Chip Supercapacitors Based on Mesoporous Silicon Coated with Ultrathin Atomic Layer-Deposited In2O3 Films.

On-chip supercapacitors have attracted considerable attention because of their high power density, long cycling life, and compatibility with integrated circuits. One critical drawback that restricts their practical application is the low energy density. In this work, low-resistivity mesoporous silicon with a high aspect ratio is prepared by Pt film-assisted chemical etching and utilized as the scaffold of the supercapacitors. Subsequently, low-resistivity (<0.0015 Ω·cm) and ultrathin In2O3 films are coated on the mesoporous silicon scaffold by atomic layer deposition at 200 °C, serving as the active electrode material. The electrochemical measurements reveal that the coating of the In2O3 film remarkably improves the performance of the supercapacitors compared with those without the In2O3 coating. The supercapacitors with a 4.5 nm In2O3 film coating exhibit a capacitance density of 1.36 mF/cm2 at a scan rate of 10 mV/s as well as a better stability against the scan rate. In addition, it is found that the pristine mesoporous silicon walls are collapsed after 400 times of sweeping while those with the In2O3 film coating are still intact even after 2000 times of sweeping. Meanwhile, a high energy density is also achieved without sacrificing the power performance.

Bioinspired Modification of Poly(L-lactic acid)/Nano-Sized ß-Tricalcium Phosphate Composites with Gelatin/Hydroxyapatite Coating for Enhanced Osteointegration and Osteogenesis.

Compared to pure poly(L-lactic acid) (PLLA), PLLA/nano-sized ß-tricalcium phosphate (PLLA/nß-TCP) composites show both superior interfacial compatibility and osteoinductive, and consequently hold great potential for bone defect repair applications. However, their dismal osteointegration limits their further development in bone regeneration, adding the need for tailored modification. In this study, a bioinspired modification approach was proposed to construct gelatinhydroxyapatite (GEL/HAP) coating onto PLLA/nß-TCP composites by combining chemical grafting with in situ reaction methods. The incorporation of the biomimetic GEL/HAP coating substantially improved MC3T3-E1 cell adhesion, proliferation and osteogenic differentiation, as demonstrated by morphological observation. Cell Counting Kit-8 (CCK-8) assay, alkaline phosphate activity test (ALP), and quantitative real-time polymerase chain reaction (qRT-PCR) analysis. Furthermore, GEL/HAP-PLLA/nß-TCP composites and their control counterparts (i.e., bare PLLA/nß-TCP) were synchronously implanted into femoral condylar defects of an identical rabbit. Characterizations including microcomputed tomography (micro-CT), histological analysis and the push-out test revealed that the biomimetic coating not only improved osteointegration but also significantly promoted bone regeneration. Overall, for the first time, bioinspired surface modification of the PLLA/nß-TCP composite with GEL/HAP coating was demonstrated to be an efficient strategy for enhancing the osteointegration and osteogenesis functions of bone implants.

Enhanced bone regeneration composite scaffolds of PLLA/ß-TCP matrix grafted with gelatin and HAp.

The composite polylactide PLLA/ß-TCP scaffolds were fabricated by solution casting and were coated with gelatin/hydroxyapatite (Gel/HAp) to improve the biological properties of the composite scaffolds. The Gel/HAp mixture was prepared using an in situ reaction, and a grafting-coating method was used to increase the efficiency of coating the PLLA/ß-TCP matrix with Gel/HAp. First, free amino groups were introduced by 1,6-hexanediamine to aminolyze the PLLA/ß-TCP matrix surface. Second, glutaraldehyde was coupled to Gel/HAp as a crosslinking agent. The structure and properties of Gel/HAp-modified PLLA/ß-TCP films were characterized by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and water contact angle measurements (WCA). The experimental results show that 23 wt% HAp was uniformly dispersed in the gelatin coating by in situ synthesis. The Gel/HAp composite coating was successfully immobilized on the aminolyzed PLLA/ß-TCP surface via a chemical grafting method, which promoted a lower degradation rate and was more hydrophilic than a physical grafting method. The Gel/HAp composite coating adhered tightly and homogeneously to the hydrophobic PLLA/ß-TCP surface. Moreover, mouse embryo osteoblast precursor (MC3T3-E1) cells grown on the scaffolds were behaviorally and morphologically characterized. The results indicated that the Gel/HAp composite coating was favorable for the attachment and proliferation of preosteoblasts and that Gel/HAp-NH-PLLA/ß-TCP would be a candidate scaffold for bone repair.

Improved cell adhesion and osteogenesis using a PLTGA (poly l-lactide, 1,3-trimethylene carbonate, and glycolide) terpolymer by gelatin-assisted hydroxyapatite immobilization for bone regeneration.

A PLTGA (poly l-lactide, trimethylene carbonate, glycolide) terpolymer possesses great potential for orthopedic applications due to its excellent biocompatibility and controllable biodegradability. However, the unfavorable surface conditions of bare PLTGA such as its poor hydrophilicity and smooth morphology impede its clinical applications, highlighting the need for tailored surface modifications to improve its cytological behavior and osteogenic capacity. We herein develop a facile and effective strategy to deposit a gelatin/hydroxyapatite (GEL/HAP) hybrid coating onto the surface of PLTGA that involves consecutive chemical grafting and in situ reaction steps. Following the surface modification treatment, the resultant PLTGA scaffold with the GEL/HAP coating exhibited drastically improved hydrophilicity (79.1°vs. 48.2° in water contact angle) and increased surface roughness (18.4 vs. 267.9 nm, more than 14-fold, in root-mean-square roughness), respectively. In addition, preosteoblast (MC3T3-E1) cells were seeded onto the bare/modified PLTGA scaffold to evaluate biological performance, including cell adhesion, proliferation, mineralization and osteogenic differentiation. Based on these results, the GEL/HAP hybrid coating can endow the PLTGA terpolymer substrate with enhanced cell adhesion, proliferation and osteogenic functionality. Overall, post-treatment of PLTGA with the GEL/HAP hybrid coating may be a promising methodology in bone regeneration applications.

Comparing different tissue-engineered repair materials for the treatment of pelvic organ prolapse and urinary incontinence: which material is better?

INTRODUCTION AND HYPOTHESIS: Synthetic non-absorbable meshes are widely used to augment surgical repair of pelvic organ prolapse (POP) and stress urinary incontinence (SUI), but these meshes are associated with serious complications. This study compares the attachment and extracellular matrix (ECM) production of adipose-derived stem cells (ADSCs) on different biodegradable nanomaterials to develop tissue engineered repair materials. METHODS: Rat ADSCs were isolated and cultured on electrospun poly-L-lactic acid (PLA) and electrospun poly(L-lactide)-trimethylene carbonate-gycolide (PLTG) terpolymers for 1 and 2 weeks. Samples were tested for cell proliferation (cell counting kit-8), microstructure, and morphology (scanning electron microscopy), production of ECM components (immunostaining for collagen I, collagen III, and elastin) and biomechanical properties (uniaxial tensile methods). RESULTS: The ADSCs showed good attachment and proliferation on both PLA and PLTG scaffolds. The production of collagen I and collagen III on both scaffolds was greater at 14 days than at 7 days and was greater on PLTG scaffolds than on PLA scaffolds, but these differences were not significant. The addition of ADSCs onto scaffolds led to a significant increase in the biomechanical properties of both PLA and PLTG scaffolds compared with unseeded scaffolds. CONCLUSION: These data support the use of both PLA and PLTG as tissue-engineered repair materials for POP or SUI.

Biodegradable PTLGA Terpolymers versus Collagen Implants Used as an Adjuvant in Trabeculectomy in Rabbit Eye.

Purpose. To evaluate the effectiveness and safety of three biodegradable terpolymers prepared from L-lactide, trimethylene carbonate, and glycolide (PTLGA) as an aid for trabeculectomy compared with the Ologen (OLO). Methods. Trabeculectomy was carried out on rabbits with implantation made from OLO or three PTLGA terpolymers. Intraocular pressure (IOP) was recorded 1, 2, 3, and 6 months postoperatively and bleb evaluations were performed using ultrasound biomicroscopy (UBM) 3 months after surgery, optical coherence tomography (OCT) every month, and transmission electron microscopy (TEM) six months after surgery followed by histological examination 1, 2, 3, and 6 months postoperatively. Result. IOP was significantly reduced in all groups after surgery. There were no significant differences in the IOL between groups at any time after implantation. There was no significant difference between the groups examined by OCT, UBM, and TEM. Exposure of the implant was observed in one eye from the OLO group and one eye in the P1. Subconjunctiva hyperblastosis was observed in one eye from group P3 and two eyes from the OLO group. Conclusions. Subconjunctival implantation of filtering devices made from PTLGA may present a safe and effective additional surgical tool for the treatment of filtering surgery. Fewer complications were observed in the group with P2 implants compared to other groups.

In vitro biocompatibility evaluation of bioresorbable copolymers prepared from L-lactide, 1, 3-trimethylene carbonate, and glycolide for cardiovascular applications.

PLLA-TMC-GA terpolymer was prepared by ring-opening polymerization of L-lactide, 1, 3-trimethylene carbonate (TMC), and glycolide (GA). The biocompatibility of terpolymer was evaluated in comparison with PLLA and PLLA-TMC with the aim of assessing their potential in the development of bioresorbable cardiovascular stents. Various aspects of in vitro biocompatibility were considered, including MTT assay, hemolytic test, dynamic clotting time, platelet adhesion, platelet activation, protein adsorption, plasma recalcification time and release of cytokines. The results revealed that the terpolymer presents good cytocompatibility and hemocompatibility. Moreover, no significant increase in the release of cytokines was detected. It is thus concluded that these polymers, in particular PLLA-TMC-GA terpolymer present good biocompatibility for cardiovascular applications.

In vivo degradation of copolymers prepared from L-lactide, 1,3-trimethylene carbonate and glycolide as coronary stent materials.

A series of high molecular weight polymers were prepared by ring opening polymerization of L-lactide (L-LA), 1,3-trimethylene carbonate (TMC) and glycolide using stannous octoate as catalyst. The resulting polymers were characterized by gel permeation chromatography, (1)H nuclear magnetic resonance, differential scanning calorimeter and tensile tests. All the polymers present high molecular weights. Compared with PLLA and PTLA copolymers, the terpolymers exhibit interesting properties such as improved toughness and lowered crystallinity with only slightly reduced mechanical strength. In vivo degradation was performed by subcutaneous implantation in rats to evaluate the potential of the copolymers as bioresorbable coronary stent material. The results show that all the polymers conserved to a large extent their mechanical properties during the first 90 days, except the strain at break which exhibited a strong decrease. Meanwhile, significant molecular weight decrease and weight loss are detected in the case of terpolymers. Therefore, the PTLGA terpolymers present a good potential for the development of totally bioresorbable coronary stents.

Degradation and osteogenic potential of a novel poly(lactic acid)/nano-sized ß-tricalcium phosphate scaffold.

The purpose of this study was to investigate the influence of nano-sized ß-tricalcium phosphate (ß-TCP) on the biological performance of poly (lactic acid) (PLA) composite scaffolds by using in vitro degradation and an in vivo model of heterotopic bone formation. Nano-sized ß-TCP (nß-TCP) was prepared with a wet grinding method from micro-sized ß-TCP (mß-TCP), and composite scaffolds containing 0, 10, 30, or 50 wt% nß-TCP or 30 wt% mß-TCP were generated using a freeze-drying method. Degradation was assessed by monitoring changes in microstructure, pH, weight, and compressive strength over a 26-week period of hydrolysis. Composite scaffolds were processed into blocks, and implanted into muscular pockets of rabbits after loading with recombinant human bone morphogenetic protein-2 (rhBMP-2). New bone formation was evaluated based on histological and immunohistochemical analysis 2, 4, and 8 weeks after implantation. The in vitro results indicated that the buffering effect of nß-TCP was stronger than mß-TCP, which was positively correlated with the content of nß-TCP. The in vivo findings demonstrated that nß-TCP enhanced the osteoconductivity of the scaffolds. Although composite scaffolds containing 30% nß-TCP exhibited similar osteoconductivity to 50% nß-TCP, they had better mechanical properties than the 50% nß-TCP scaffolds. This study supports the potential application of a composite scaffold containing 30% nß-TCP as a promising scaffold for bone regeneration.

Enzyme-catalyzed degradation of biodegradable polymers derived from trimethylene carbonate and glycolide by lipases from Candida antarctica and Hog pancreas.

Enzyme-catalyzed degradation of poly(trimethylene carbonate) homo-polymer (PTMC) and poly(trimethylene carbonate-co-glycolide) co-polymer (PTGA) was investigated in the presence of lipases from Candida antarctica and Hog pancreas. Degradation was monitored by gravimetry, size-exclusion chromatography (SEC), nuclear magnetic resonance (NMR), tensiometry and environmental scanning electron microscopy (ESEM). PTMC can be rapidly degraded by Candida antarctica lipase with 98% mass loss after 9 days, while degradation by Hog pancreas lipase leads to 27% mass loss. Introduction of 16% glycolide units in PTMC chains strongly affects the enzymatic degradation. Hog pancreas lipase becomes more effective to PTGA co-polymer with a mass loss of 58% after 9 days, while Candida antarctica lipase seems not able to degrade PTGA. Bimodal molecular weight distributions are observed during enzymatic degradation of both PTMC and PTGA, which can be assigned to the fact that the surface is largely degraded while the internal part remains intact. The composition of the PTGA co-polymer remains constant, and ESEM shows that the polymers are homogeneously eroded during enzymatic degradation. Contact angle measurements confirm the enzymatic degradation mechanism, i.e., enzyme adsorption on the polymer surface followed by enzyme-catalyzed chain cleavage.

Phase behaviors of cyclic diblock copolymers.

A spectral method of self-consistent field theory has been applied to AB cyclic block copolymers. Phase behaviors of cyclic diblock copolymers, such as order-disorder transition, order-order transition, and domain spacing size, have been studied, showing good consistency with previous experimental and theoretical results. Compared to linear diblocks, cyclic diblocks are harder to phase separate due to the topological constraint of the ring structure. A direct disorder-to-cylinder transition window is observed in the phase diagram, which is significantly different from the mean field phase diagram of linear diblock copolymers. The domain spacing size ratio between cyclic and linear diblock copolymers is typically close to 0.707, indicating in segregation that the cyclic polymer can be considered to be made up of linear diblocks with half of the original chain length.

[Characterization of surface properties of 1,3,5-triamino-2,4,6-trinitrobenzene by inverse gas chromatography].

The surface properties of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) with various particle sizes were characterized by inverse gas chromatography (IGC). The disperse component gamma s(d) of surface free energy of TATB samples increased as temperature increased. The larger the particle size is, the quicker the increasing rate of the disperse component will be as the temperature increases. The gamma s(d) of the coarse TATB is the highest (193.2 mJ/m2) and that of the submicron TATB is the smallest (64.0 mJ/m2) at 353 K. Due to the different preparation processes and particle sizes, the samples show obviously different Lewis acid-base properties. Fine TATB can provide positive Lewis acid-base active sites and has higher acidity. The specific components of the adsorption of polar probes on the surface of the other three types of TATB were found to be endothermic owing to the strong hydrogen bond of inter- and intra-TATB molecules. Their surface acidity and basicity constants, K(a) and K(b) are negative.