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Supplementary Figure S5: Attenuation of tumor-suppressing effects of miR-490-3p by SMARCD1 overexpression.

Supplementary Table S1: Absolute expression levels of miR-490-3p, miR-375 and let-7b in non-cancerous gastric mucosa.

Chromatin remodeling has emerged as a hallmark of gastric cancer, but the regulation of chromatin regulators other than genetic change is unknown. Helicobacter pylori causes epigenetic dysregulation to promote gastric carcinogenesis, but the roles and functions of microRNAs (miRNA) in this multistage cascade are not fully explored. In this study, miRNA expression in preneoplastic and neoplastic lesions in murine stomachs induced by H. pylori and N-methyl-N-nitrosourea (MNU) was profiled by miRNA expression array. miR-490-3p exhibited progressive downregulation in gastritis, intestinal metaplasia, and adenocarcinoma during H. pylori and MNU-induced gastric carcinogenesis. Significant downregulation of miR-490-3p was confirmed in human gastric cancer tissues in which its regulatory region was found to be hypermethylated. miR-490-3p exerted growth- and metastasis-suppressive effects on gastric cancer cells through directly targeting SMARCD1, a SWItch/Sucrose NonFermentable (SWI/SNF) chromatin remodeling complex subunit. Knockdown of SMARCD1 significantly attenuated the protumorigenic effects of miR-490-3p inhibitor, whereas enforced expression of SMARCD1 promoted in vitro and in vivo oncogenic phenotypes of gastric cancer cells. SMARCD1 was markedly upregulated in gastric cancer in which its high expression was associated with shortened patients' survival independent of TNM staging. In conclusion, hypermethylation-mediated silencing of miR-490-3p reactivates SMARCD1 to confer malignant phenotypes, mechanistically linking H. pylori, chromatin remodeling, and gastric carcinogenesis. Cancer Res; 75(4); 754–65. ©2014 AACR.

Supplementary Materials and Methods

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This study aimed to examine the plant diversity and plant performance of vertical greening system (VGS) and how the hardware setup (including growing substrates) potentially affect plant performance. A total of 125 VGS (including 85 outdoor and 40 indoor VGS) were surveyed in Hong Kong. We recorded the type of VGS, species composition, frequency and plant coverage; substrate medium type, and plant performance. The findings revealed that indoor soilless VGS performed comparably well as on conventional soil, and outdoor soilless VGS performed significantly better than on soil. Regardless of substrate type, plants on indoor VGS performed better than outdoor VGS. Keywords: Vertical greening system; Floristic composition; Growing medium; Plant performance eISSN: 2398-4287© 2020. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. DOI: https://doi.org/10.21834/ebpj.v5i14.2268

No standard of care for mucosal melanoma (MM) in the adjuvant setting has been established. Meanwhile, relapse-free survival (RFS) is only ∼5 months after surgery alone. This phase II trial aimed to compare toripalimab versus high-dose interferon-α2b (HDI) as an adjuvant therapy for resected MM.From July 2017 to May 2019, 145 patients with resected MM were randomized (1 : 1) to receive HDI (n = 72) or toripalimab (n = 73) for 1 year until disease relapse/distant metastasis, unacceptable toxicity, or withdrawal of consent. The primary endpoint was RFS. The secondary endpoints included distant metastasis-free survival (DMFS), overall survival (OS), and safety.After a median follow-up of 26.3 months, the number of RFS, OS, and DMFS events was 51 versus 46, 33 versus 29, and 49 versus 44 in the toripalimab arm and the HDI arm, respectively. The median RFS was 13.6 [95% confidence interval (CI) 8.31-19.02] months and 13.9 (95% CI 8.28-19.61) months in the toripalimab arm and the HDI arm, respectively. The DMFS was not significantly different between the two arms [hazard ratio (HR) 1.00; 95% CI 0.65-1.54]. The median OS was 35.1 months (95% CI 27.93 months-not reached) in the toripalimab arm, with no significant difference in all-cause death (HR 1.11, 95% CI 0.66-1.84) for the two arms. The median sums of the patients' actual infusion doses were 3672 mg and 1054.5 MIU in the toripalimab arm and the HDI arm, respectively. The incidence of treatment-emergent adverse events with a grade ≥3 was much higher in the HDI arm than in the toripalimab arm (87.5% versus 27.4%).Toripalimab showed a similar RFS and a more favorable safety profile than HDI, both better than historical data, suggesting that toripalimab might be the better treatment option. However, additional translational studies and better treatment regimens are still warranted to improve the clinical outcome of MM.

Background: Perioperative neurocognitive disorders (PND) occur frequently in elderly patients after surgery, but the mechanism of PND is not very clear at present. It is reported that anesthesia/surgery could cause intestinal flora imbalance and induce neurocognitive impairment. However, the effect of intestinal flora on PND is poorly understood. We previously found that peripheral interleukin-17A (IL17A) destroyed the blood-brain barrier (BBB), leading to central inflammation and neurocognitive impairment. The small intestine is the main place where Th17 cells are produced. Therefore, we hypothesized that Th17 cells and IL-17 may be an important bridge for intestinal microbes to cause neuroinflammation. Methods: Exploratory laparotomy was performed to establish PND model under sevoflurane anesthesia. 16S rRNA high-throughput sequencing was used to detect the changes of intestinal flora. To explore the relationship between intestinal flora and PND, compound antibiotics were used to eliminate intestinal flora before anesthesia/surgery, and behavior tests, such as open field, Y maze, and fear conditioning tests were applied to detect the changes of memory ability and which was compared with the rats that did not receive compound antibiotics. The number of Th17 cells and Foxp3 cells was detected by flow cytometry in the Peyer's patches (PP), mesenteric lymph nodes (MLN), blood and brain. Hippocampus IL17, IL17RA, IL6 and IL10 were detected by Western blot. Hippocampus IL17, IL17R and IBA1 (ionized calcium binding adaptor molecule1) were detected by immunofluorescence. Results: Anesthesia/surgery caused intestinal flora imbalance and induced neurocognitive impairment, increased the number of Th17 cells in the PP, MLN, blood and brain, up-regulated the lever of IL17, IL17R and inflammatory factor production in the hippocampus. The administration of compound antibiotics before anesthesia/surgery evidently inhibited this effect, including decreased the number of Th17 cells, down-regulated the lever of IL17, IL17R and inflammatory factor production, and improved the memory function. In addition, we found that IL17R was co-labeled with IBA1 in a large amount in the hippocampus through immunofluorescence double-staining. Conclusion: Our study suggested that intestinal dysbacteriosis-propelled T helper 17 cells activation might play an important role in the pathogenesis of PND.

In addition to human cases, cases of COVID-19 in captive animals and pets are increasingly reported. This raises the concern for two-way COVID-19 transmission between humans and animals. Here, we developed a SARS-CoV-2 nucleocapsid protein-based competitive enzyme-linked immunosorbent assay (cELISA) for serodiagnosis of COVID-19 which can theoretically be used in virtually all kinds of animals. We used 187 serum samples from patients with/without COVID-19, laboratory animals immunized with inactive SARS-CoV-2 virions, COVID-19-negative animals, and animals seropositive to other betacoronaviruses. A cut-off percent inhibition value of 22.345% was determined and the analytical sensitivity and specificity were found to be 1:64–1:256 and 93.9%, respectively. Evaluation on its diagnostic performance using 155 serum samples from COVID-19-negative animals and COVID-19 human patients showed a diagnostic sensitivity and specificity of 80.8% and 100%, respectively. The cELISA can be incorporated into routine blood testing of farmed/captive animals for COVID-19 surveillance.

Compared to other human coronaviruses, the genetic diversity and evolution of human coronavirus 229E (HCoV-229E) are relatively understudied. We report a fatal case of COVID-19 pneumonia coinfected with HCoV-229E in Hong Kong. Genome sequencing of SARS-CoV-2 and HCoV-229E from a nasopharyngeal sample of the patient showed that the SARS-CoV-2 strain HK13 was most closely related to SARS-CoV-2 type strain Wuhan-Hu-1 (99.99% nucleotide identity), compatible with his recent history of travel to Wuhan. The HCoV-229E strain HK20-42 was most closely related to HCoV-229E strain SC0865 from the United States (99.86% nucleotide identity). To investigate if it may represent a newly emerged HCoV-229E genotype in Hong Kong, we retrieved 41 archived respiratory samples that tested positive for HCoV-229E from 2004 to 2019. Pneumonia and exacerbations of chronic airway diseases were common among infected patients. Complete RdRp, S, and N gene sequencing of the 41 HCoV-229E strains revealed that our contemporary HCoV-229E strains have undergone significant genetic drift with clustering of strains in chronological order. Two novel genogroups were identified, in addition to previously described genogroups 1 to 4, with recent circulating strains including strain HK20-42 belonging to novel genogroup 6. Positive selection was detected in the spike protein and receptor-binding domain, which may be important for viral evolution at the receptor-binding interphase. Molecular dating analysis showed that HCoV-229E shared the most recent common ancestor with bat and camel/alpaca 229E-related viruses at ∼1884, while camel/alpaca viruses had a relatively recent common ancestor at ∼1999. Further studies are required to ascertain the evolutionary origin and path of HCoV-229E. IMPORTANCE Since its first appearance in the 1960s, the genetic diversity and evolution of human coronavirus 229E (HCoV-229E) have been relatively understudied. In this study, we report a fatal case of COVID-19 coinfected with HCoV-229E in Hong Kong. Genome sequencing revealed that our SARS-CoV-2 strain is highly identical to the SARS-CoV-2 strain from Wuhan, compatible with the patient’s recent travel history, whereas our HCoV-229E strain in this study is highly identical to a recent strain in the United States. We also retrieved 41 archived HCoV-229E strains from 2004 to 2019 in Hong Kong for sequence analysis. Pneumonia and exacerbations of chronic airway diseases were common diagnoses among the 41 patients. The results showed that HCoV-229E was evolving in chronological order. Two novel genogroups were identified in addition to the four preexisting HCoV-229E genogroups, with recent circulating strains belonging to novel genogroup 6. Molecular clock analysis dated bat-to-human and bat-to-camelid transmission to as early as 1884.

To control the COVID-19 pandemic and prevent its resurgence in areas preparing for a return of economic activities, a method for a rapid, simple, and inexpensive point-of-care diagnosis and mass screening is urgently needed. We developed and evaluated a one-step colorimetric reverse-transcriptional loop-mediated isothermal amplification assay (COVID-19-LAMP) for detection of SARS-CoV-2, using SARS-CoV-2 isolate and respiratory samples from patients with COVID-19 (n = 223) and other respiratory virus infections (n = 143). The assay involves simple equipment and techniques and low cost, without the need for expensive qPCR machines, and the result, indicated by color change, is easily interpreted by naked eyes. COVID-19-LAMP can detect SARS-CoV-2 RNA with detection limit of 42 copies/reaction. Of 223 respiratory samples positive for SARS-CoV-2 by qRT-PCR, 212 and 219 were positive by COVID-19-LAMP at 60 and 90 min (sensitivities of 95.07% and 98.21%) respectively, with the highest sensitivities among nasopharyngeal swabs (96.88% and 98.96%), compared to sputum/deep throat saliva samples (94.03% and 97.02%), and throat swab samples (93.33% and 98.33%). None of the 143 samples with other respiratory viruses were positive by COVID-19-LAMP, showing 100% specificity. Samples with higher viral load showed shorter detection time, some as early as 30 min. This inexpensive, highly sensitive and specific COVID-19-LAMP assay can be useful for rapid deployment as mobile diagnostic units to resource-limiting areas for point-of-care diagnosis, and for unlimited high-throughput mass screening at borders to reduce cross-regional transmission.

A lead-free SnTe compound shows good electrical property but high thermal conductivity, resulting in a low figure-of-merit ZT. We present a significant enhancement of the thermoelectric properties of p-type SnTe with (Ag, In) co-doping. The Ag and In co-doped Sn1−2x Ag x In x Te (x = 0.00, 0.01, 0.02, 0.03, 0.04 and 0.05) are prepared by melting, quenching and spark plasma sintering. A homogeneous NaCl-type SnTe-based solid solution forms in the alloys at low Ag and In content (x ≤ 0.02), while a AgInTe2 minor secondary phase precipitates for higher x. Similar to In doping, the introduction of Ag and In at Sn sites in SnTe considerably increases the Seebeck coefficient and power factor by creating resonant levels near the Fermi energy. In addition, the Ag and In solute atoms in the SnTe-based solid solution and the minor secondary phase AgInTe2 enhance phonon scattering and thus significantly reduce the carrier and lattice thermal conductivity. Ag and In co-doping shows a collective advantage on the overall thermoelectric performance of SnTe or In-doped SnTe. A maximum ZT of 1.23 at 873 K and average ZT of 0.58 can be obtained in the alloy Sn1−2x Ag x In x Te with x = 0.03.

Since its first appearance in 2012, Middle East respiratory syndrome (MERS) has affected >25 countries, with >2,400 cases and an extremely high fatality rate of >30%. The total number of mortalities due to MERS is already greater than that due to severe acute respiratory syndrome. MERS coronavirus (MERS-CoV) has been confirmed to be the etiological agent. So far, dromedaries are the only known animal reservoir for MERS-CoV. Previously published serological studies showed that sera of Bactrian camels were all negative for MERS-CoV antibodies. In this study, we observed that 41% of the Bactrian camel sera and 55% of the hybrid camel sera from Dubai (where dromedaries are also present), but none of the sera from Bactrian camels in Xinjiang (where dromedaries are absent), were positive for MERS-CoV antibodies. Based on these results, we conclude that in addition to dromedaries, Bactrian and hybrid camels are also potential sources of MERS-CoV infection., So far, dromedary camels are the only known animal reservoir for Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV). Previous published serological studies showed that sera of Bactrian camels were all negative for MERS-CoV antibodies. However, a recent study revealed that direct inoculation of Bactrian camels intranasally with MERS-CoV can lead to infection with abundant virus shedding and seroconversion. In this study, we examined the presence of MERS-CoV antibodies in Bactrian and hybrid camels in Dubai, the United Arab Emirates (where dromedaries are also present), and Bactrian camels in Xinjiang, China (where dromedaries are absent). For the 29 serum samples from Bactrian camels in Dubai tested by the MERS-CoV spike (S) protein-based enzyme-linked immunosorbent assay (S-ELISA) and neutralization antibody test, 14 (48%) and 12 (41%), respectively, were positive for MERS-CoV antibodies. All the 12 serum samples that were positive with the neutralization antibody test were also positive for the S-ELISA. For the 11 sera from hybrid camels in Dubai tested with the S-ELISA and neutralization antibody test, 6 (55%) and 9 (82%), respectively, were positive for MERS-CoV antibodies. All the 6 serum samples that were positive for the S-ELISA were also positive with the neutralization antibody test. There was a strong correlation between the antibody levels detected by S-ELISA and neutralizing antibody titers, with a Spearman coefficient of 0.6262 (P 25 countries, with >2,400 cases and an extremely high fatality rate of >30%. The total number of mortalities due to MERS is already greater than that due to severe acute respiratory syndrome. MERS coronavirus (MERS-CoV) has been confirmed to be the etiological agent. So far, dromedaries are the only known animal reservoir for MERS-CoV. Previously published serological studies showed that sera of Bactrian camels were all negative for MERS-CoV antibodies. In this study, we observed that 41% of the Bactrian camel sera and 55% of the hybrid camel sera from Dubai (where dromedaries are also present), but none of the sera from Bactrian camels in Xinjiang (where dromedaries are absent), were positive for MERS-CoV antibodies. Based on these results, we conclude that in addition to dromedaries, Bactrian and hybrid camels are also potential sources of MERS-CoV infection.

In order to prepare Re doped aluminide coating, an effective and low-cost method of electroplating Ni-Re layer and subsequent low temperature high activity pack cementation method was used. Re-doped Ni2Al3 coating was consisted of an outer Ni2Al3 layer with dispersed Re-rich precipitates, a middle Ni2Al3 layer with dispersed W-rich precipitates and a bottom layer of interdiffusion zone (IDZ). Interestingly, Re existed in the outer coating in form of fine Re-rich precipitates because of low solid solubility of Re in Ni2Al3. [Al] was produced and absorbed on the surface of Ni-Re layer, and the activity of Al was far higher than that of Ni during pack cementation at 800 °C. Thus, Re-doped Ni2Al3 coating was mainly formed by virtually singular inward diffusion of [Al] through the Ni2Al3 layer.

Both series of stoichiometric Sn1 − xMnxTe and non-stoichiometric Sn1 − yMn1.1yTe alloys were prepared through melting, quenching and spark plasma sintering to investigate their phases and thermoelectric properties. The experimental results show that the SnTe-based solid solution single phase was formed in both series of samples with lower Mn content. The minor secondary MnTe2 phase was formed in the stoichiometric Sn1 − xMnxTe alloys with x ≥ 0.06 due to the Mn needed for filling in the intrinsic Sn lattice vacancies of SnTe and volatilization lost during the preparation. The excess Mn in Sn1 − yMn1.1yTe alloys compensates this need to avoid the formation of block MnTe2 phase, which changed the phase relationship and guaranteed more Mn effectively substituting Sn in SnTe. All the samples show p-type conduction. The substitution of Mn in SnTe enhances its Seebeck coefficient and reduces its thermal conductivity. Much greater improvement on thermoelectric properties was found in the non-stoichiometric Sn1 − yMn1.1yTe alloys, resulting in the maximum figure of merit ZT of 1.22 in Sn0.9Mn0.11Te alloy at 873 K, due to more Mn substituting for Sn in SnTe lattice. The excess Mn in the non-stoichiometric Sn1 − yMn1.1yTe alloys is important for preparing the Mn-doped SnTe materials with high thermoelectric property. Keywords: SnTe compound, Mn substitution, Non-stoichiometric, Thermoelectric properties

Enhancer of zeste homolog 2 (EZH2) catalyses histone H3 lysine 27 trimethylation (H3K27me3) to silence tumour-suppressor genes in hepatocellular carcinoma (HCC) but the process of locus-specific recruitment remains elusive. Here we investigated the transcription factors involved and the molecular consequences in HCC development. The genome-wide distribution of H3K27me3 was determined by chromatin immunoprecipitation coupled with high-throughput sequencing or promoter array analyses in HCC cells from hepatitis B virus (HBV) X protein transgenic mouse and human cell models. Transcription factor binding site analysis was performed to identify EZH2-interacting transcription factors followed by functional characterization. Our cross-species integrative analysis revealed a crucial link between Yin Yang 1 (YY1) and EZH2-mediated H3K27me3 in HCC. Gene expression analysis of human HBV-associated HCC specimens demonstrated concordant overexpression of YY1 and EZH2, which correlated with poor survival of patients in advanced stages. The YY1 binding motif was significantly enriched in both in vivo and in vitro H3K27me3-occupied genes, including genes for 15 tumour-suppressive microRNAs. Knockdown of YY1 reduced not only global H3K27me3 levels, but also EZH2 and H3K27me3 promoter occupancy and DNA methylation, leading to the transcriptional up-regulation of microRNA-9 isoforms in HCC cells. Concurrent EZH2 knockdown and 5-aza-2'-deoxycytidine treatment synergistically increased the levels of microRNA-9, which reduced the expression and transcriptional activity of nuclear factor-κB (NF-κB). Functionally, YY1 promoted HCC tumourigenicity and inhibited apoptosis of HCC cells, at least partially through NF-κB activation. In conclusion, YY1 overexpression contributes to EZH2 recruitment for H3K27me3-mediated silencing of tumour-suppressive microRNAs, thereby activating NF-κB signalling in hepatocarcinogenesis.

Microstructural evolution and compressive properties of two-phase Nb-Fe binary alloys based on the C14 Laves phase NbFe2 were characterized at both the hypo- and hypereutectic compositions. The experimental results indicated that the microstructures of the two alloys consisted of fully eutectics containing Fe and NbFe2 phases at the bottom of the ingots corresponding to the largest solidification rates. With the decrease of solidification rate, the microstructures developed into primary Fe (NbFe2) dendrites plus eutectics in the middle and top parts of the ingots. The microstructural evolutions along the axis of the ingots were analyzed by considering the competitive growth between the primary phase and eutectic as well as using microstructure selection models based on the maximum interface temperature criterion. Furthermore, the compressive properties of the two alloys were measured and the enhancements were explained in terms of the second Fe phase and halo toughening mechanisms.

Composites of nominal composition (Pb0.96Na0.04Te)1 − x(Sm2Se3)x with x = 0, 0.005, 0.015, 0.02, 0.025, 0.040 and 0.050 have been synthesized to study their thermoelectric properties. In these composites, Sm2Se3 is the secondary phase. It increases the hole carrier concentration due to more Na dissolved in the PbTe-based solid solution by replacing Te with Se, but decreases its carrier mobility. The Sm2Se3 reduces the power factor slightly, but reduces the thermal conductivity significantly. As a result, the figure of merit ZT can be enhanced with proper Sm2Se3 content. The highest ZT achieved is 1.5 in the composite with x = 0.025.

The microstructures of binary Cr/Cr2Nb alloys doped with 0.1 at-% rare earth element (REE) Y were characterised by fine interlamellar spacing, and the growth morphology of Cr2Nb primary phase was transformed from faceted to non-faceted. Moreover, the lamellar spacing was observed to decrease with the decreasing of solidification rate with the addition of REE Y. Furthermore, the mechanical tests showed that the addition of REE Y has a beneficial effect on the room temperature fracture toughness of Cr2Nb/Cr alloys. The room temperature fracture toughness of the Y doped Cr/Cr2Nb hypoeutectic and hypereutectic alloys increased by ∼130 and 140% over that of the undoped alloys respectively, which was caused by the refinement of lamellar eutectic and strengthening of lamellar eutectic bonding strength.

By employing XRD, EDXS, TEM, HRTEM, and SADPs methods, the polytypic transition of Laves phase Cr2Nb alloyed with Ti has been investigated in the dual-phase Cr–20Nb–40Ti (in at.%) alloy. The solute Ti in Cr2Nb is shown to inhibit the polytypic transition of Cr2Nb by substituting onto the Cr sites. This leads to the occurrence of metastable structures of C36, 5R, 6H and 7R. On the contrary, the second phase β-Ti is suggested to prompt the polytypic transition of Cr2Nb based on the lattice mismatch calculation. The low lattice mismatch between the β-Ti and the C15 polytype is beneficial to the formation of single C15 polytype at the interface.

The effect of Ti content on the fracture toughness of the Cr 2 Nb–20/30/40Ti (in at.%) alloys has been investigated in the arc melting and heat treatment (1473 K for 48 h) conditions. The results show that the reduction of grain size and the facture toughness of the alloys increased with increasing the Ti content. After the heat treatment, the facture toughness of the Cr 2 Nb–20/30Ti alloys increased by almost twice, and the crack bridging was primarily observed as the toughening mechanism, and for the Cr 2 Nb–40Ti alloy, the fracture toughness increased by 77% and reached 18.80 MPa m 1/2 , and the toughening mechanism transited to the crack defection. The alleviation of deformation constraint during the heat treatment was elucidated to be effective in improving the fracture toughness of the alloys.

Kinesiology tape (KinTape) is a therapeutic tape without much understanding of its mechanism. KinTape claims to increase cutaneous stimulation, which facilitates motor unit firing, and consequently improves functional performance; however these, benefits could be due to placebo effects. This study investigated the true effects of KinTape by a deceptive, randomized, and controlled trial. Thirty healthy participants performed isokinetic testing of three taping conditions: true facilitative KinTape, sham KinTape, and no KinTape. The participants were blindfolded during the evaluation. Under the pretense of applying adhesive muscle sensors, KinTape was applied to their quadriceps in the first two conditions. Normalized peak torque, normalized total work, and time to peak torque were measured at two angular speeds (60°/s and 180°/s) and analyzed with one-way repeated measures ANOVA. Participants were successfully deceived and they were ignorant about KinTape. No significant differences were found between normalized peak torque, normalized total work, and time to peak torque at 60°/s or 180°/s (p = 0.31-0.99) between three taping conditions. The results showed that KinTape did not facilitate muscle performance in generating higher peak torque, yielding a greater total work, or inducing an earlier onset of peak torque. These findings suggest that previously reported muscle facilitatory effects using KinTape may be attributed to placebo effects.

Compared to the enormous species diversity of bats, relatively few parvoviruses have been reported. We detected diverse and potentially novel parvoviruses from bats in Hong Kong and mainland China. Parvoviruses belonging to Amdoparvovirus, Bocaparvovirus and Dependoparvovirus were detected in alimentary, liver and spleen samples from 16 different chiropteran species of five families by PCR. Phylogenetic analysis of partial helicase sequences showed that they potentially belonged to 25 bocaparvovirus, three dependoparvovirus and one amdoparvovirus species. Nearly complete genome sequencing confirmed the existence of at least four novel bat bocaparvovirus species (Rp-BtBoV1 and Rp-BtBoV2 from Rhinolophus pusillus, Rs-BtBoV2 from Rhinolophus sinicus and Rol-BtBoV1 from Rousettus leschenaultii) and two novel bat dependoparvovirus species (Rp-BtAAV1 from Rhinolophus pusillus and Rs-BtAAV1 from Rhinolophus sinicus). Rs-BtBoV2 was closely related to Ungulate bocaparvovirus 5 with 93, 72.1 and 78.7 % amino acid identities in the NS1, NP1 and VP1/VP2 genes, respectively. The detection of bat bocaparvoviruses, including Rs-BtBoV2, closely related to porcine bocaparvoviruses, suggests recent interspecies transmission of bocaparvoviruses between bats and swine. Moreover, Rp-BtAAV1 and Rs-BtAAV1 were most closely related to human AAV1 with 48.7 and 57.5 % amino acid identities in the rep gene. The phylogenetic relationship between BtAAVs and other mammalian AAVs suggests bats as the ancestral origin of mammalian AAVs. Furthermore, parvoviruses of the same species were detected from multiple bat species or families, supporting the ability of bat parvoviruses to cross species barriers. The results extend our knowledge on the diversity of bat parvoviruses and the role of bats in parvovirus evolution and emergence in humans and animals.

Astroviruses cause gastrointestinal and neurological infections in humans and animals. Since astrovirus is genetically diverse and different astrovirus genotypes can be found in the same animal species, astrovirus is a potential zoonotic threat to humans. In this study, we screened for astroviruses in rodents from Hong Kong, Hunan and Guangxi. Astrovirus was detected in 11.9 % (67/562) of rectal swab specimens. Phylogenetic analysis of the ORF1b region, which encodes the RdRp, showed that there were four distinct clusters (clusters A, B, C and D). Whole genome sequencing was performed for 11 representative strains from each of these four clusters. The mean amino acid genetic distances (p-dist) of full-length ORF2 were >0.634 between clusters A, B, C and other known astroviruses. The p-dist between clusters A and B, A and C, and B and C were 0.371-0.375, 0.517-0.549 and 0.524-0.555, respectively. Within cluster C, the p-dist between HN-014 and GX-006 was 0.372. Since strains with p-dist of ≥0.368 in ORF2 are now considered to be of separate genotypes species, cluster A, cluster B, cluster C-HN-014 and cluster C-GX-006 can be classified as novel genotype species. Cluster D was most closely related to the rodent astrovirus previously identified in Hong Kong. Since rodents live in close proximity to humans, interspecies jumping of these novel astroviruses may represent a threat to human health.

The microstructure and room temperature fracture toughness of binary Cr/Cr2Nb alloys annealed at 1653 K for 30 h were investigated at both the hypo- and hypereutectic compositions. The experimental results indicate that the high temperature heat treatment has a beneficial effect on the room temperature fracture toughness of the Cr2Nb/Cr alloys. After the heat treatment, the room temperature fracture toughness of the hypo- and hypereutectic alloys are increased by about 212 and 203%, which are 15 and 8 times higher than that of as-cast Cr2Nb Laves phase (1·2 MPa m1/2). The fractographic analysis indicates that in the annealed condition, the strengthen of lamellar eutectic cohesive strength can provide significant toughening of the matrix by crack deflection, crack blunting and crack bridging mechanisms.

The microstructure and mechanical properties of Cr2Nb-based intermetallic matrix composites fabricated by laser surface remelting were investigated at hypoeutectic and hypereutectic compositions. In the hypoeutectic composition, the molten zones under different laser scanning velocities consist of fully α-Cr dendrites, whereas a series of morphology evolutions perpendicular to the scanning direction occurred in the hypereutectic composition: Cr2Nb primary phase + Cr/Cr2Nb eutectic → Cr/Cr2Nb eutectic → α-Cr primary phase + Cr/Cr2Nb eutectic → fully α-Cr dendrite. Based on the maximum growth rate criterion, the microstructure evolutions of the molten zones were analyzed by considering the competitive growth among the α-Cr phase, Cr2Nb Laves phase, and the Cr/Cr2Nb eutectic, which are in agreement with the experimental results. More importantly, the room-temperature fracture toughness values of the hypoeutectic and hypereutectic alloys attain 11.2 MPa m1/2 and 7.9 MPa m1/2, respectively, which increase by eight and six times over the as-cast Cr2Nb Laves phase (1.2 MPa m1/2), respectively. The remarkable enhancements in room-temperature fracture toughness were explained in terms of fine-grain toughening, second Cr phase toughening, and point defects toughening.

Molecular dynamics (MD) simulations are performed to study the mechanical properties of nanocomposite of carbon nanotube (CNT) encapsulating a Si 16 -fullerene-linked nanowires (Si 16 NW). It is found that Si 16 NW is not coaxial with CNT. Instead, it is adsorbed and hence closer to one side of the internal wall of CNT by forming strong sp 3 bonds. These sp 3 bonds can greatly enhance the limit of CNT against torsional and bending deformation. Due to the protection of CNT, the encapsulated Si 16 NW can maintain its configuration at relatively high torsional angle. The axial Young’s modulus of the freestanding Si 16 NW is found to be more than that of bulk Si and much larger than that of the Si nanowires of similar size. Furthermore, the interfacial sp 3 bonds resulted in a strong enhancement of axial maximum strength of encapsulated Si 16 NW. However, it is interesting that filling Si 16 NW into (13, 0) CNT does not enhance the axial tensile strength and elastic modulus of the host CNT.

A series of microstructures including fully coupled eutectic, both α-Cr and β-Cr2Nb primary dendrites embedded in eutectic and only β-Cr2Nb primary dendrites plus eutectic were observed in the arc-melted Cr-Cr2Nb eutectic alloy. By employing EPMA analysis performed at the eutectic regions, the eutectic composition of the Cr-Cr2Nb system was indicated to contain less than 18 at.%Nb. Based on the solidification phase selection involving phase competitive nucleation and growth, the α-Cr phase was predicted to be the primary nucleating phase and the β-Cr2Nb the primary growing phase. Under large undercooling conditions, the solidification process was controlled by nucleation, which led to the formation of α-Cr primary particles. With the decrease in undercooling, the solidification process developed into growth controlling, which caused the occurrence of β-Cr2Nb primary phase since the actual solidification path of the alloy lay within the hypereutectic region. The explanation was confirmed by the experimental composition analysis.

The microstructure and mechanical properties of a binary Cr based alloy containing the Laves phase Cr2Nb and Cr phase have been studied in the arc melted condition. Microstructure consisting of fine directional divorced eutectic was observed at the bottom of the ingot, while it developed into coarse Cr primary dendrites plus interdendritic lamellar eutectic containing Cr2Nb and Cr phases in the middle and top parts of the ingot. Meanwhile, the fracture toughness values of the top and bottom parts of the ingot attained 4·5 and 7·8 MPa m1/2 at room temperature, which were about three and five times than that of monolithic Cr2Nb respectively. The enhancement was explained by the second Cr phase toughening and grain refinement toughening mechanisms. In addition, the formation mechanism of the divorced eutectic and the microstructure–property relationships were also discussed.

Haloes of Laves phase Cr2Nb around the primary dendrites Cr were observed in the arc-melted Cr–12% Nb hypoeutectic alloy, while no halo of non-faceted Cr phase around the Cr2Nb Laves phase occurred in the Cr–20% Nb hypereutectic alloy. This observation differs from the haloes formed in metal–intermetallic alloy systems. An explanation on the formation of Cr2Nb halo was presented by considering the solidification behavior of the leading phase and non-reciprocal nucleation characteristics of the Cr2Nb/Cr eutectic. In the Cr–12% Nb alloy, primary dendrites Cr worked as a good nucleant available for the occurrence of the halo Cr2Nb that subsequently solidified as the leading phase in the eutectic. For the Cr–20% Nb alloy, primary dendrites Cr2Nb first precipitated as the leading phase inducing the eutectic formation, resulting in no halo growth. In addition, the coupled zone of the Cr–Nb alloy was theoretically predicted in agreement with the experimental results.

Applying a melt-fluxing method, a substantial degree of undercooling up to 220 K has been obtained for Cu50Co50 immiscible alloy and the non-equilibrium solidification microstructure is investigated considering the successive processes of undercooling, liquid separation, non-equilibrium and near-equilibrium solidification. For samples undercooled by 62, 79 and 105 K, grain refinement occurs and becomes more serious without the occurrence of liquid separation and peritectic transformation. In contrast, metastable liquid demixing occurs upon the undercooling reaching 125 K, and it proceeds completely with the further increase of undercooling to 188 and 220 K, which can be ascribed to the sufficient time through the immiscible region. After liquid separation, versatile solidification microstructure for Co-rich and Cu-rich regions can be observed due to the different non-equilibrium effect. Moreover, second liquid separation becomes more serious for higher undercooling because of the enhanced immiscible effect. Finally, the solute content of primary Co-rich phase was analyzed with the consideration of solute trapping and liquid immiscible effects, which gives an excellent explanation for the variation of hardness behavior.

Microstructure of the arc-melted Cr-20at%Nb alloy solidified in different positions was investigated using optical microscope (OM) and scanning electron microscope (SEM). The results show that fully coupled eutectic was developed at the bottom of the ingot and then the eutectic experienced a columnar to equiaxed transition due to the decrease of G/V ratio (G the thermal gradient and V the solidification rate) with increasing the solidification distance. A novel lamellar structure was observed in the middle side of the arc-melted ingot, which may form by means of the eutectoid reaction of C14-Cr2Nb→C15-Cr2Nb+Crss. With the increase of the solidification distance from the middle side to the top side, the primary Cr2Nb phase underwent a nonfaceted to faceted transition.

A simple and effective approach of employing an abrupt increase in growth velocity is presented to obtain entirely coupled eutectics in directional solidification of off-eutectic alloys. Using the proposed approach, the velocity required for the growth of entirely coupled eutectics in off-eutectic alloys can be increased remarkably. In directionally solidified Al–40 wt% Cu hypereutectic alloys with a thermal gradient of 250 K/cm, primary Al2Cu dendrites appeared at constant growth velocities ranging from 5 to 100 μm/s and entirely coupled eutectics formed at 1 μm/s. Employing the abrupt increase in growth velocity, the growth velocity of purely coupled eutectics could attain 100 μm/s.