Construction of porous carbon for the highly efficient visible light-driven degradation methyl violet

A series of nanoporous carbons (NPC) Fe-C/N-900 and C/N-900 have been synthesized from one-step carbonization of 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin-Fe (Fe-TCPP) and TCPP, respectively and employed as photocatalyst for the degradation of organic dye methyl violet (MV) under UV irradiation. The optimized Fe-C/N-900 (carbonized at 900 oC for 2 h) exhibited an optimal performance in MV degradation. The photodegradation capacity of Fe-C/N-900 has been observed to be higher than that of C/N-900. The photodegradation ability of Fe-C/N-900 as a function of initial MV concentration, catalysis dosage, and pH has been also investigated. The Fe-C/N-900 material showed no apparent loss in MV degradation after four cycles. These features reveal that Fe-C/N-900 may be a promising degradant for dyes removal from water.                     KEY WORDS: Photocatalysis, Nanoporous carbons, Methyl violet, carbonization   Bull. Chem. Soc. Ethiop. 2020, 34(2), 277-284 DOI: https://dx.doi.org/10.4314/bcse.v34i2.6

Aesthetic functional reconstruction of the mutilated hand: Indications and selection of reconstructive techniques

Advances in microsurgery together with improvements in reconstructive surgical techniques over recent decades have enlarged the scope of available techniques for mutilated hand reconstruction, shifting the reconstructive paradigm from restoring hand function to providing the best functional and aesthetic results with minimal donor-site morbidity. Successful reconstruction of a mutilated hand should no longer be measured only by the degree of improvement of hand function but also by a more aesthetic hand appearance as well as by improved psychological well-being. In this article, the authors present their concept of aesthetic functional reconstruction of the mutilated hand with a focus on the indications and selection of reconstructive techniques. They emphasize that in order to select the most appropriate technique, providing the best functional and aesthetic outcomes with minimal donor-site morbidity for each individual patient, it is imperative for the reconstructive hand surgeon to possess perfect mastery of all available surgical techniques, thorough understanding of functional and aesthetic requirements and accurate appreciation of multidimensional reconstruction of a given defect of the hand. They have concluded that in precisely indicated cases, successful replantation of an amputated hand or digits remains the best reconstructive procedure designed to obtain a more functional and more normal-appearing hand, whereas, toe-to-hand transplantation, in cases of failed or impossible digit replantation, provides better results than any other digit reconstruction techniques aimed at achieving functioning digits with good appearance. Although skin graft and various distant pedicled flaps and free flaps may be valid options for coverage of some soft tissue defects of the hand, reverse flow forearm flaps, especially those based on the secondary arteries of the forearm, are often the best-suited reconstructive options for like-with-like hand reconstruction. They can provide the best matching of color, texture, soft-tissue volume, donor-recipient tissue interface and fulfill all the aesthetic and functional reconstruction requirements of moderate-sized or even large soft tissue defects of the hand, with acceptable donor site morbidity.

Coverage of cutaneous substance loss in the leg: Techniques and indications

Cutaneous substance loss in the leg is frequent; more often than not, it is trauma-related. It calls for complex management and necessitates the application of all current reconstruction techniques, particularly microsurgery. As regards treatment, the available therapeutic arsenal is highly diversified, ranging from a simple free flap skin graft to local and locoregional flaps. During reconstruction, the surgeon is subjected to several constraints insofar as the objectives of the operation are esthetic as well as functional. Ideally, the fineness of the skin covering the anterior side of the leg will have been scrupulously respected. Reconstruction is aimed at producing a stable and reliable cutaneous envelope while limiting the morbidity of the donor site. The development of free perforator flaps corresponds to these two criteria by producing a fine flap adapted to the cutaneous thickness of the leg and limiting any functional and esthetic sequelae at the donor site.

Effect of salt concentration on microbial communities, physicochemical properties and metabolite profile during spontaneous fermentation of Chinese northeast sauerkraut

AIM

The aim of this study was to study the effects of salt concentrations on the microbial communities, physicochemical properties, metabolome profiles and sensory characteristics during the fermentation of traditional northeast sauerkraut.

METHODS AND RESULTS

Northeast sauerkraut was spontaneously fermented under four salt concentrations (0·5, 1·5, 2·5 and 3·5%, w/w). The result of microbiological analysis showed that the population of lactic acid bacteria in 2·5%-salted sauerkraut was significantly higher than that in the other samples. Correspondingly, the speed of decrease in pH and accumulation of acids were the highest in 2·5%-salted sauerkraut. The glucose (analysed by HPLC) in 2·5%-salted sauerkraut was consumed more completely to produce higher levels of organic acids compared to those in the other samples. Principle component analysis showed clear differences in the metabolites of sauerkraut according to different salt concentrations. A higher level of volatiles (detected by HS-SPME/GC-MS) was identified in 2·5%-salted sauerkraut, and sensory evaluation demonstrated that 2·5%-salted sauerkraut had the best sensory characteristics.

CONCLUSION

The best quality of sauerkraut was obtained from fermented under 2·5% salt concentration.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study facilitated the understanding of the effects of salt on the sauerkraut fermentation and may be useful for developing the quality of sauerkraut.

Recent progress on the Chinese space programme and radiation research

Manned space exploration was initiated in China in 1992, and substantial progress has been made. The next step is to build the Chinese Space Station (CSS), which is planned to be launched in 2020. The CSS will provide an on-orbit laboratory for experimental studies including space radiation research. The health risk of space radiation, especially carcinogenesis, is a major concern for long-term space exploration. Establishing a risk assessment system suitable for Chinese astronauts and developing effective countermeasures are major tasks for Chinese space radiobiologists. The Institute of Space Life Sciences, Soochow University has focused on these topics for years. We established cancer models with low-dose-rate exposure of alpha particles, and elucidated a microRNA-TGFβ network regulating bystander effects and a lncRNA-cytoskeleton network regulating genomic instability induced by ionising radiation. We also confirmed the radioresistance of quiescent cells, which inspires a potential strategy to improve individual radioresistance during long-term space travel. However, we believe that a multi-disciplinary strategy must be developed to protect astronauts from highly energised space radiation.

Measurement of CP-Averaged Observables in the B^{0}→K^{*0}μ^{+}μ^{-} Decay

An angular analysis of the B^{0}→K^{*0}(→K^{+}π^{-})μ^{+}μ^{-} decay is presented using a dataset corresponding to an integrated luminosity of 4.7  fb^{-1} of pp collision data collected with the LHCb experiment. The full set of CP-averaged observables are determined in bins of the invariant mass squared of the dimuon system. Contamination from decays with the K^{+}π^{-} system in an S-wave configuration is taken into account. The tension seen between the previous LHCb results and the standard model predictions persists with the new data. The precise value of the significance of this tension depends on the choice of theory nuisance parameters.

Observation of New Ξ_{c}^{0} Baryons Decaying to Λ_{c}^{+}K^{-}

The Λ_{c}^{+}K^{-} mass spectrum is studied with a data sample of pp collisions at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 5.6  fb^{-1} collected by the LHCb experiment. Three Ξ_{c}^{0} states are observed with a large significance and their masses and natural widths are measured to be m[Ξ_{c}(2923)^{0}]=2923.04±0.25±0.20±0.14  MeV, Γ[Ξ_{c}(2923)^{0}]=7.1±0.8±1.8  MeV, m[Ξ_{c}(2939)^{0}]=2938.55±0.21±0.17±0.14  MeV, Γ[Ξ_{c}(2939)^{0}]=10.2±0.8±1.1  MeV, m[Ξ_{c}(2965)^{0}]=2964.88±0.26±0.14±0.14  MeV, Γ[Ξ_{c}(2965)^{0}]=14.1±0.9±1.3  MeV, where the uncertainties are statistical, systematic, and due to the limited knowledge of the Λ_{c}^{+} mass. The Ξ_{c}(2923)^{0} and Ξ_{c}(2939)^{0} baryons are new states. The Ξ_{c}(2965)^{0} state is in the vicinity of the known Ξ_{c}(2970)^{0} baryon; however, their masses and natural widths differ significantly.

[Identification and functional study of the Schistosoma japonicum epidermal growth factor receptor gene]

OBJECTIVE

To characterize the epidermal growth factor receptor (EGFR) gene in Schistosoma japonicum (SjEGFR gene) and investigate the role of the EGFR gene in regulating the growth, reproductive system, maturation and fecundity of S. japonicum.

METHODS

Rapid amplification of cDNA ends (RACE) was performed to obtain the full length of the SjEGFR gene, and the SjEGFR gene expression was quantified in different developmental stages of S. japonicum using a quantitative real-time PCR (qPCR) assay. The tissue localization of the SjEGFR gene was detected in 22-day parasite using whole-mount in situ hybridization (WISH). Following RNA interference (RNAi)-induced knockdown of the SjEGFR gene, the worm length, pairing rate and worm burden of S. japonicum were measured, and the worm morphology was observed using optical microscopy and confocal microscopy.

RESULTS

The SjEGFR gene was identified with a conserved tyrosine-kinase active site, and the SjEGFR gene expression was detected at various developmental stages in male and female parasites. WISH showed that the transcript of the SjEGFR gene was localized on the tegument and in the digestive organs of S. japonicum. RNAi-induced SjEGFR knockdown resulted in marked suppression of the worm growth, smaller size of male testicles that contained more immature spermatocytes, and apparent impairment of ovary and vitelline gland development. In addition, no eggs were found in the uterus of SjEGFR knocked-down female parasites, indicating the interruption of egg production.

CONCLUSIONS

Inhibition of SjEGFR expression may remarkably suppress the growth and maturation of S. japonicum, and interrupt the egg production.