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As a visible-light response semiconductor materials, bismuth vanadate (BiVO4) is extensively applied in photodegradation organic dye field. In this study, we synthesized C3N5 nanosheets and coupled with decahedral BiVO4 to construct a Z-scheme C3N5/BiVO4 heterostructure with close interface contact. By introducing C3N5 into BiVO4, the built Z-scheme transfer pathway provides silky channel for charge carrier migration between different moieties and enables photoexcited electrons and holes accumulated on the surface of BiVO4 and C3N5. The accelerated separation of charge carriers ensures C3N5/BiVO4 heterostructures with a powerful oxidation capacity compared with pure BiVO4. Due to the synergistic effect in Z-scheme heterostructure, the C3N5/BiVO4 demonstrated an improved photodegradation ability of rhodamine B (RhB) and methylene blue (MB) that of bare BiVO4. [ABSTRACT FROM AUTHOR]

Introducing piezoelectric materials with the built-in electric field caused by mechanical force has been confirmed as an effective strategy to boost the separation efficiency of photoexcited charge carriers that determines the photocatalytic performance. In this study, we introduced Bi4Ti3O12 with superior piezoelectric properties into BiVO4–Bi4V2O10 materials to synthesize a 2D Bi4Ti3O12–BiVO4–Bi4V2O10 photocatalyst via a facile hydrothermal method. Compared with bare BiVO4, the Bi4Ti3O12–BiVO4–Bi4V2O10 piezo-photocatalytic activity towards Cr(VI) removal and oxygen evolution is boosted remarkably under both illumination and ultrasound treatments. The promoted photocatalytic activity can be ascribed to the accelerated photoexcited carrier separation efficiency driven by the polarization electric field and the synergy effect in the heterostructure. This work provides a simple and sustainable strategy for the design and development of piezo-photocatalysts with high photoredox activity capacity. [ABSTRACT FROM AUTHOR]

Poly (lactic acid) (PLA) has been proposed as a promising orthopedic implant material, whereas insufficient mechanical strength, unsatisfied biocompatibility and inappropriate degradation rate restrict its further application. In this work, self‐reinforced poly (lactic acid)‐b‐poly(lactide‐co‐caprolactone) (PLA‐b‐PLCL) block copolymer with long‐chain branches was fabricated through two‐stage orientation. Compared with smooth and hydrophobic PLA surface, the surface of PLA‐b‐PLCL presented micro‐phase separated structure with improved hydrophilicity, and cells seeded on it showed improved adhesion/proliferation and high alkaline phosphatase (ALP) activity. After the 1st stage orientation at temperature higher than Tg1 (glass transition temperature of PLA phase), the amount of CH3 and CO groups on surface of PLA‐b‐PLCL increased, while "groove‐ridge" structure formed, resulting in enhancement of surface hydrophobicity. After the 2nd stage orientation at Tg1 ~ Tg2 (glass transition temperature of PLCL phase), surface hydrophobicity/amount of CO groups further increased and "groove‐ridge" structure became more significant. Due to suitable wettability and enhanced material‐cell mechanical interlocking, cell proliferation/ALP activity were improved and a continuous cell layer formed on sample surface. During in vitro degradation in phosphate buffered saline solution, by introduction of PLCL segments, the crystallinity decreased and solution absorption increased, resulting in a rapid deterioration of mechanical properties. After the 1st stage orientation, a dense microfibrillar structure with high crystallinity formed, which hindered diffusion of solution and delay hydrolytic degradation. After the 2nd stage orientation, PLCL segments were arranged more closely, resulting in a further inhibition of degradation, which was helpful for controlling the strength decay rate of PLA as bone fixation materials. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C3N4) possesses fascinating merits, but its practical applications are limited by the inferior properties of limited visible-light sorption, rapid recombination of photo-excited charge carriers and low electrical conductivity. Introduction of N-defects is an efficient approach to tune its optical properties, but strategies capable of creating abundant vacancies and simultaneously maintaining the highly crystalline architecture are still limited and highly desired. In this work, a facile construction methodology was demonstrated to afford g-C3N4 with abundant N vacancies, high crystallinity, a hydrophilic surface structure, a small particle size, and an increased surface area under neat and mild conditions. The essence of our approach lies in the treatment of the bulk g-C3N4 precursor with an alkaline salt (LiN(SiMe3)2) with a low melting point, moderate nucleophilicity, and easy removal procedures. The unique structural properties of the afforded ND-g-C3N4 allow for a significantly redshifted absorption edge and enhanced charge carrier separation, leading to superior photocatalytic hydrogen evolution performance three times that obtained by pristine g-C3N4. The modification strategy developed herein sheds light on the fabrication of g-C3N4-based materials with improved photocatalytic efficiency via efficient introduction of N defects, variation of the surface structure, and retention of the high crystallinity. [ABSTRACT FROM AUTHOR]

Photocatalytic evolution of hydrogen and oxygen from water splitting over semiconductors is an efficient method for solar energy conversion. In this study, the 2D/2D BiVO4−CdS heterostructures with Ti3C2Tx (Tx=O, OH, F) as a co‐catalyst were synthesized by two steps as the visible‐light‐driven photocatalysts. Compared with BiVO4 and CdS, the heterostructured catalysis exhibit greatly enhanced photocatalytic hydrogen and oxygen production performances and excellent photodegradation and photoreduction activities of methylene blue (MB) and potassium dichromate Cr(VI), respectively. The remarkable enhancement is attributed to the proposed Z‐scheme carrier transfer derived from the 2D/2D BiVO4−CdS heterostructures. Charge separation and transfer of photoexcited electrons and holes pairs are further enhanced after loading Ti3C2Tx in the BiVO4−CdS heterostructures. The potential Z‐scheme photocatalytic system and co‐catalyst endows the BiVO4−CdS−Ti3C2Tx heterostructures with strong photo‐redox capacity and excellent stability in solar energy conversion. [ABSTRACT FROM AUTHOR]

Giardia intestinalis, a cosmopolitan zoonotic parasite, is one of the most common causes of protozoal diarrhea in both humans and animals worldwide. Although G. intestinalis has been detected in many animals, information regarding its prevalence and genotype in Chinese racehorses is scarce. In the present study, we investigated the prevalence of G. intestinalis in racehorses and performed molecular characterization of the pathogen to assess its zoonotic potential. Two hundred and sixty-four racehorse fecal samples from six equestrian clubs located in different regions of the Sichuan province of southwestern China were examined. Nested polymerase chain reaction (PCR) analysis of the gene encoding triose-phosphate isomerase (tpi) showed the prevalence of G. intestinalis to be 8.3% (22/264), and the prevalence in different clubs varied from 3.6% to 13.5%. Three assemblages were identified in the successfully sequenced samples, including the potentially zoonotic assemblages A (n = 5) and B (n = 14), the mouse-specific assemblage G (n = 3), and a mixed A and B assemblage. Sequence analysis of tpi, glutamate dehydrogenase (gdh), and beta giardin (bg) loci revealed that the majority of sequences isolated from assemblage A were identical to the subtype AIV and assemblage B isolates showed variability among the nucleotide sequences of the subtype BIV. Using the nomenclature for the multilocus genotype (MLG) model, one each of multilocus genotypes A (MLG1) and B (MLG2) were identified, with MLG2 being a novel genotype. To the best of our knowledge, this is the first study to investigate G. intestinalis in Chinese racehorses. The presence of both animal and human assemblages of G. intestinalis in racehorses indicated that these animals might constitute a potential zoonotic risk to human beings. [ABSTRACT FROM AUTHOR]

A total of 333 fecal specimens from horses in southwestern China were genotyped based on analysis of the small subunit rRNA ( SSU rRNA) gene. Cryptosporidium hominis and Cryptosporidium andersoni were identified in 2 and 4 stool specimens, respectively. The identification of C. hominis was confirmed by sequence analysis of the 70- kDa heat shock protein ( HSP70) and oocyst wall protein ( COWP) genes. Subtyping analysis of the 60- kDa glycoprotein ( GP60) gene sequence of C. hominis revealed a new rare subtype Id, named IdA15; only three Id isolates have been reported in humans to date. Multilocus sequence typing ( MLST) analysis indicated that the C. andersoni subtype was A6, A5, A2, and A1 at the four minisatellite loci ( MS1, MS2, MS3, and MS16, respectively). This is the first report to identify the presence of C. andersoni and C. hominis in horses in southwestern China and the first to identify a rare zoonotic subtype Id of C. hominis in horses. These findings suggest that infected horses may act as potential reservoirs of Cryptosporidium to transmit infections to humans. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen evolution over semiconductors is an efficient method for solar-energy conversion. Heterostructural photocatalysts with separated photoexcited carriers exhibit efficient photocatalytic hydrogen evolution without co-catalysts. In this study, heterostructures comprising of Cd 1-x Zn x S and Zn 1-y Cd y S phases were prepared through the replacement and sulfuration process at high temperature using Zn powders as the precursor. Highly crystalline Cd 1-x Zn x S-Zn 1-y Cd y S heterostructures without noble metal co-catalysts present a stable and highly effective photocatalytic hydrogen evolution rate under both UV–visible and visible-light irradiations due to the synergistic effects of Cd 1-x Zn x S and Zn 1-y Cd y S. [ABSTRACT FROM AUTHOR]

Enterocytozoon bieneusi is an obligate eukaryotic intracellular parasite that infects a wide variety of vertebrate and invertebrate hosts. Although considerable research has been conducted on this organism, relatively little information is available on the occurrence of E. bieneusi in captive Asiatic black bears. The present study was performed to determine the prevalence, genetic diversity, and zoonotic potential of E. bieneusi in captive Asiatic black bears in zoos in southwestern China. Fecal specimens from Asiatic black bears in four zoos, located in four different cities, were collected and analyzed for the prevalence of E. bieneusi. The average prevalence of E. bieneusi was 27.4% (29/106), with the highest prevalence in Guiyang Zoo (36.4%, 16/44). Altogether, five genotypes of E. bieneusi were identified among the 29 E. bieneusi-positive samples, including three known genotypes (CHB1, SC02, and horse2) and two novel genotypes named ABB1 and ABB2. Multi-locus sequence typing using three microsatellites (MS1, MS3, and MS7) and one minisatellite (MS4) revealed V, III, V, and IV genotypes at these four loci, respectively. Phylogenetic analysis showed that the genotypes SC02 and ABB2 were clustered into group 1 of zoonotic potential, the genotypes CHB1 and ABB1 were clustered into a new group, and the genotype horse2 was clustered into group 6 of unclear zoonotic potential. In conclusion, this study identified two novel E. bieneusi genotypes in captive Asiatic black bears, and used microsatellite and minisatellite markers to reveal E. bieneusi genetic diversity. Moreover, our findings show that genotypes SC02 (identified in humans) and ABB2 belong to group 1 with zoonotic potential, suggesting the risk of transmission of E. bieneusi from Asiatic black bears to humans and other animals. [ABSTRACT FROM AUTHOR]

• rGO-MA hybrid was prepared by grafted with MA via amidation and reduction reaction. • rGO-MA was exfoliated and uniformly dispersed in POM matrix via hydrogen bonding. • Adding rGO-MA made FEA of POM decrease by 50.8%, and E a increased notably. • Synergistic thermo-oxidative stabilization mechanism of rGO-MA on POM was explored. Formaldehyde emission produced by polymer degradation would cause serious environment pollution. Melamine (MA) as highly efficient formaldehyde scavenger has been widely applied in polyoxymethylene (POM) industry. However, the volatilization, migration and physical loss of MA during processing and application have become a serious problem for POM production. In this work, MA was first grafted onto graphene oxide (GO) surface through amidation reaction, and reduced graphene oxide-g-melamine (rGO-MA) hybrid was prepared by subsequent reduction. The POM/rGO-MA nano-composite was then manufactured via conventional melt processing. By incorporation of MA, hydrogen bonding was enhanced for composite, and POM molecules were intercalated into reduced graphene oxide (rGO) layers effectively with high intercalation ratio, while rGO was exfoliated and uniformly distributed in POM matrix. Compared with neat POM, the formaldehyde emission amount (FEA) of POM/rGO-MA decreased notably by 50.8%, and the thermal degradation temperature and degradation activation energy (E a) were improved significantly. Meanwhile, the retention of mechanical property of POM/rGO-MA remained stable, while melt index increased much slowly during thermo-oxygen aging process. By grafting MA onto rGO surface, both the thermal migration resistance of MA and radical scavenging ability of GO were enhanced, while rGO-MA exhibited excellent synergistic removal effect of formaldehyde generated by POM degradation. Besides, the composite showed extraordinary oxygen barrier property, and thermal oxidation degradation of POM was delayed effectively. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Enterocytozoon bieneusi, the most commonly identified microsporidian species in humans, is also identified in livestock, birds, rodents, reptiles, companion animals, even wastewater. However, there is no information available on occurrence of E. bieneusi in pet chipmunks. The aim of the present study was to determine the genotypes, molecular characterization of E. bieneusi in pet chipmunks, and assess the zoonotic potential. Results: A total of 279 fecal specimens were collected from chipmunks from seven pet shops and one breeding facility in Sichuan province, China. The prevalence for E. bieneusi was 17.6% (49/279) based on nested PCR targeting the internal transcribed spacer (ITS) region. The prevalence of E. bieneusi in chipmunks < 90 days of age was significantly higher than that in older chipmunks; however, differences among different sources and between genders were not significant. Eight genotypes of E. bieneusi were identified, including four known genotypes (D, Nig7, CHG9, and CHY1) and four novel genotypes (SCC-1 to 4). Phylogenetic analysis classified these genotypes into four distinct groups as follows: genotypes D and CHG9 clustered into group 1 of zoonotic potential; genotypes Nig7 and CHY1 clustered into group 6 and a new group, respectively; the four novel genotypes (SCC-1 to 4) formed a separate group named group 10. Conclusions: To the best of our knowledge, this is the first study reporting the prevalence and genotypes of E. bieneusi in pet chipmunks in China. Genotypes D and Nig7, found in chipmunks in this study, have also been previously identified in humans, which suggests that chipmunks might play a role in the transmission of this pathogen to humans. [ABSTRACT FROM AUTHOR]

The construction of Z-scheme heterostructures using matching band semiconductors is an effective strategy for producing highly efficient photocatalysts. In this study, MgIn 2 S 4 (MIS) was grown in situ on In 2 O 3 microrods created with an In-based MOF material (In-MIL-68) as a template to successfully establish a unique MIS-In 2 O 3 heterojunction with a well-matched Z-scheme interface charge transfer channel. Tetracycline (TC) as a typical antibiotic was chosen as the target pollutant to evaluate the photocatalytic activity. After 120 min of visible light irradiation, the MIS-In 2 O 3 -(10:1) material had the greatest photocatalytic degradation activity of tetracycline with 96.55%, which was 2.39 and 4.26 times that of MIS and In 2 O 3 , respectively. The improved photocatalytic activity is attributed to the in situ growth of MIS on In 2 O 3 , forming a Z-scheme heterojunction at the interface, which not only increases the specific surface area, exposes the abundant active site, and improves light utilization but also facilitates the migration and separation of photogenic carriers. The photocatalytic degradation products of TC were detected by liquid chromatography-mass spectrometry (LC-MS), and a preliminary degradation pathway was proposed. Radical capture experiments and ESR analysis confirmed that the main active species were holes (h + ), superoxide radicals ( • O 2 - ), and superoxide and hydroxyl radicals ( • OH). Finally, combined with band position analysis, this study proposes a direct Z-scheme heterojunction mechanism to improve the photocatalytic degradation of tetracycline in MIS under visible light.

Introducing piezoelectric materials with the built-in electric field caused by mechanical force has been confirmed as an effective strategy to boost the separation efficiency of photoexcited charge carriers that determines the photocatalytic performance. In this study, we introduced Bi 4 Ti 3 O 12 with superior piezoelectric properties into BiVO 4 -Bi 4 V 2 O 10 materials to synthesize a 2D Bi 4 Ti 3 O 12 -BiVO 4 -Bi 4 V 2 O 10 photocatalyst via a facile hydrothermal method. Compared with bare BiVO 4 , the Bi 4 Ti 3 O 12 -BiVO 4 -Bi 4 V 2 O 10 piezo-photocatalytic activity towards Cr(VI) removal and oxygen evolution is boosted remarkably under both illumination and ultrasound treatments. The promoted photocatalytic activity can be ascribed to the accelerated photoexcited carrier separation efficiency driven by the polarization electric field and the synergy effect in the heterostructure. This work provides a simple and sustainable strategy for the design and development of piezo-photocatalysts with high photoredox activity capacity.

Bismuth vanadate (BiVO 4 ) is a promising photocatalyst for water pollution degradation and photocatalytic oxygen evolution. In this work, we prepared 2D/2D BiVO 4 -Bi 4 V 2 O 10 heterostructure with tight interfacial contact via a facile one-step hydrothermal process. The crystal structure and morphology of the samples could be easily regulated by changing the pH values of the solution. The BiVO 4 -Bi 4 V 2 O 10 heterostructure exhibited an enhanced photodegradation rate of Cr(VI) and oxygen evolution that of bare BiVO 4 , indicating that the synergistic effect and the interfacial fusions between BiVO 4 and Bi 4 V 2 O 10 can effectively promote the migration and separation rate of photoexcited charge carriers.

Background: Enterocytozoon bieneusi is one of the most prevalent causative species of diarrhea and enteric diseases in various hosts. E. bieneusi has been identified in humans, mammals, birds, rodents and reptiles in China, but few studies have reported E. bieneusi in horses. Therefore, the present study was conducted to assess the prevalence, molecular characteristics and zoonotic potential of E. bieneusi among horses in southwestern China., Findings: Three hundred and thirty-three fecal specimens were collected from horses on five farms in the Sichuan and Yunnan provinces of southwestern China. The prevalence of E. bieneusi was 22.5 % (75/333), as determined by nested polymerase chain reaction and sequencing analysis of the internal transcribed spacer region of the ribosomal RNA gene of E. bieneusi. Altogether, 10 genotypes were identified among the 75 E. bieneusi-positive samples: four of these genotypes were known (horse1, horse2, SC02 and D) and six were novel (SCH1-4 and YNH1-2). Multilocus sequence typing using three microsatellites (MS1, MS3 and MS7) and one minisatellite (MS4) revealed three, two, three and three genotypes at these four loci, respectively. In phylogenetic analysis, all the genotypes of E. bieneusi obtained in this study were clustered into three distinct groups: D, SC02 and SCH1-3 were clustered into group 1 (zoonotic potential); SCH4 was clustered into group 2 (cattle-hosted); whereas horse2, YNH1 and YNH2 were clustered into group 6 (unclear zoonotic potential)., Conclusions: This is the first report of E. bieneusi among horses in southwestern China. This is also the first multilocus genotyping analysis using microsatellite and minisatellite markers of E. bieneusi in horses. The presence of genotype D, which was previously identified in humans, and genotypes SC02 and SCH1-3, which belong to potential zoonotic group 1, these results indicate that horses are a potential source of human E. bieneusi infections in China.