Photosynthetic System Based on a Polyoxometalate-Based Dehydrated Metal-Organic Framework for Nitrogen Fixation.

In nature, biological nitrogen fixation is accomplished through the π-back-bonding mechanism of nitrogenase, which poses significant challenges for mimic artificial systems, thanks to the activation barrier associated with the N≡N bond. Consequently, this motivates us to develop efficient and reusable photocatalysts for artificial nitrogen fixation under mild conditions. We employ a charge-assisted self-assembly process toward encapsulating one polyoxometalate (POM) within a dehydrated Zr-based metal-organic framework (d-UiO-66) exhibiting nitrogen photofixation activities, thereby constructing an enzyme-mimicking photocatalyst. The dehydration of d-UiO-66 is favorable for facilitating nitrogen chemisorption and activation via the unpaired d-orbital electron at the [Zr6O6] cluster. The incorporation of POM guests enhanced the charge separation in the composites, thereby facilitating the transfer of photoexcited electrons into the π* antibonding orbital of chemisorbed N2 for efficient nitrogen fixation. Simultaneously, the catalytic efficiency of SiW9Fe3@d-UiO-66 is enhanced by 9.0 times compared to that of d-UiO-66. Moreover, SiW9Fe3@d-UiO-66 exhibits an apparent quantum efficiency (AQE) of 0.254% at 550 nm. The tactics of "working-in-tandem" achieved by POMs and d-UiO-66 are extremely vital for enhancing artificial ammonia synthesis. This study presents a paradigm for the development of an efficient artificial catalyst for nitrogen photofixation, aiming to mimic the process of biological nitrogen fixation.

Photochemical Ammonia Synthesis over Reduced Polyoxovanadate-Intercalated Defective ZnAl Layered Double Hydroxide Nanosheets.

The exploration of efficient and stable N2 fixation photocatalysts featuring a broad absorption spectrum and N2 fixation active sites has become specifically conspicuous. Herein, a series of reduced polyoxovanadates (POVs) were intercalated into copper-induced ZnAl layered double hydroxide (0.5%-ZnAl LDH) nanosheets with oxygen vacancies via an anion exchange strategy toward green ammonia production. The intervalence charge transfer arising from mixed-valence POV materials is responsible for its light-harvesting behavior, and the LDHs lay the foundation for the chemical adsorption and activation process of nitrogen molecules; both contributions facilitate the nitrogen photofixation performance of such composite materials. As predicted, the catalytic efficiency of V34/0.5%-ZnAl is 7.0 times higher than 0.5%-ZnAl LDH. Therefore, such an all-inorganic system exhibits an apparent quantum efficiency of 0.3137% at 500 nm. The strategy of "working in tandem" established by POV-based light-absorber species and oxygen vacancies as the sites for N2 activation is extremely vital for enhanced ammonia formation. This work opens up a versatile insight for the rational design of an efficient photo-driven nitrogen-reduction composite catalyst toward sustainable ammonia production compared to the industrial Haber-Bosch process.

Plasmonic enhanced piezoelectric photoresponse with flexible PVDF@Ag-ZnO/Au composite nanofiber membranes.

The coordination of piezoelectric and plasmonic effects to regulate the separation and migration of photo-generated carriers is still a significant method to improve the performance of visible-light photoresponse. Herein, we propose the PVDF@Ag-ZnO/Au composite nanofiber membranes utilizing the piezoelectric and plasmonic effects to promote the photocatalytic degradation of organic dyes. Here, ZnO nanorods can generate a built-in electric field under vibration to separate electron-hole pairs. The Schottky junction formed by noble metal/semiconductor can not only inhibit the recombination of photo-generated carriers and accelerate the migration of carriers, but also enhance the utilization of visible light. In addition, the structure has excellent flexibility and easy recycling characteristics. We demonstrate that the plasmonic effect of noble metal can enhance the light response of membranes and broaden light absorption from ultraviolet to visible light region. With the help of the surface-enhanced Raman scattering (SERS), modulation effects of the piezoelectric effect on light response is proved. For catalytic processes, rhodamine B (98.8%) can be almost completely degraded using PVDF@Ag-ZnO/Au within 120 minutes in the piezoelectric photocatalysis process, which is 2.2 and 2.8 times higher than photocatalysis and piezoelectric catalysis, respectively. This work provides a promising strategy for harnessing solar and mechanical energy.

Defected MoS2 Modified by Vanadium-Substituted Keggin-Type Polyoxometalates as Electrocatalysts for Triiodide Reduction in Dye-Sensitized Solar Cells.

The rational design of efficient triiodide reduction reaction catalysts that are dependent on cheap and ample elements on Earth has become a challenge. As an extremely encouraging non-noble metallic catalyst, MoS2 requires effective strategies to improve the site accessibility, inherent conductivity, and structural stability. Here, vanadium-substituted Keggin-type polyoxometalates (POMs) can be used as electron aggregates to modify manganese (Mn)-doped MoS2 through the electrochemical deposition strategy, thereby improving the charge transfer ability of MoS2 to I-/I3- redox pairs and accelerating the reduction of I3-. Additionally, with the increase in the number of vanadium atoms substituted in POMs, the conduction band of POMs and MoS2 can also match better, which effectively reduces the energy loss and is more conducive to charge transfer. Meanwhile, the deposition of POMs can improve the stability of metastable MoS2. When POMs/MoS2 materials are used as the counter electrodes of dye-sensitized solar cells, the power conversion efficiency (PCE) obtained is 7.27%, which is higher than that of platinum (Pt) (6.07%). The PCE can still maintain the initial 96% after 9 days. This work provides a valuable way for the improvement of platinum-free catalysts with minimal expense, basic process, high efficiency, and good stability.

Polyoxometalates-Based Semi-flexible Metal-Semiconductor Triboelectric Nanogenerators for Low Frequency and Small Amplitude Mechanical Energy Harvesting.

The development of high-performance and low-cost durable triboelectric nanogenerators (TENGs) is essential for converting mechanical energy into electrical energy. Many organic polymer friction materials used widely have thermal stability problems, which makes TENGs with semiconductors as friction materials stand out. Here, we report a semi-flexible TENG based on metal and TiO2 modified by polyoxometalates (POMs) as pure inorganic friction materials. Six different POMs are firstly selected to modify the friction materials of TENGs, and the output performance of TENGs with different POMs-modified semiconductors and different metals as friction materials are tested. Compared with the unmodified TENGs, the open-circuit voltage (VOC ) of the optimal Ag-K6 P2 Mo18 O62 (P2 Mo18 )/TiO2 TENG device is increased by more than 4 times, which is mainly attributed to the strong electron-accepting and storage capabilities of POMs. This study has demonstrated that TENGs modified by POMs have potential application prospects and provided a new method for increasing the electrical output of TENGs.

Heteropoly Blue/Protonation-Defective Graphitic Carbon Nitride Heterojunction for the Photo-Driven Nitrogen Reduction Reaction.

The establishment of a heterojunction is a crucial strategy to design highly effective nonnoble metal nanocatalysts for the photocatalytic nitrogen reduction reaction (PNRR). Heteropoly blues (r-POMs) can act as electron-transfer mediators in PNRR, but its agglomeration limits the further promotion of PNRR productivity. In this work, we construct a protonation-modified surface of N-vacancy g-C3N4 (HV-C3N4), achieving the high dispersion of r-POMs via the surface modification strategy. Enlightened by the synergy effect of the nitrogenase, r-POMs were anchored onto HV-C3N4 nanosheets through an electrostatic self-assembly method for preparing r-POMs-based protonation-defective graphitic carbonitride (HV-C3N4/r-POMs). As an electron donor, r-PW12 can match with the energy level of HV-C3N4 to build a heterojunction. The electron redistribution of the heterojunction facilitates the optimization of the electronic structure for enhancing the performance of PNRR. HV-C3N4/r-PW12 exhibits the best PNRR efficiency of 171.4 µmol L-1 h-1, which is boosted by 94.39% (HV-C3N4) and 86.98% (r-PW12). The isotope 15NH4+ experiment proves that ammonia is derived from N2, not carbon nitride. This study opens up a crucial view to achieve the high dispersion of r-POMs nanoparticles and develop high-efficiency nonnoble metal photocatalysts for the PNRR.

Polyoxometalate-Derived Multi-Component X/W2 C@X,N-C (X=Co, Si, Ge, B, and P) Nanoelectrocatalysts for Efficient Triiodide Reduction in Dye-Sensitized Solar Cells.

Multi-component tungsten carbide-based hybrid materials featuring different heteroatom dopants coated with X,N dual-doped carbon layers (X/W2 C@X,N-C, XWXNC) were prepared by selecting Keggin-type polyoxometalates (POMs) (NH4 )n [XW12 O40 ] (X=Co, Si, Ge, B, and P) and dicyandiamide (DCA) as precursors. The electrocatalytic activity of these nanocomposites as counter electrode (CE) catalysts for dye-sensitized solar cells (DSSCs) was systematically investigated. Structure characterizations show that X,N heteroatoms were successfully introduced into the W2 C and carbon frameworks. The obtained X,N dual-doped carbon layers were modified and loaded with W2 C nanoparticles, promoting the improvement of catalytic performance by a synergistic effect. The consequence of photoelectric conversion efficiency (PCE) is CoWCoNC (6.68 %)>SiWSiNC (6.56 %)>GeWGeNC (6.49 %)>BWBNC (6.45 %)>PWPNC (6.20 %)>WNC (6.05 %). With the increase in electronegativity of the dopants, the photovoltaic performance decreases in a reverse order. This work provides a shortcut to the rational design of highly efficient and cost-effective catalysts for DSSCs.

Astragaloside-IV regulates endoplasmic reticulum stress-mediated neuronal apoptosis in a murine model of Parkinson's disease via the lincRNA-p21/CHOP pathway.

OBJECTIVES: Astragaloside-IV (AS-IV) protects the nerve cells of Parkinson's disease (PD) from damage. Long non-coding RNA (lincRNA) has been found to be important for many diseases. Lincnra-p21 is abnormally expressed in PD. The purpose of this study was to investigate whether Astragaloside-IV (AS-IV) affects endoplasmic reticulum stress (ERS)-induced neuronal apoptosis in PD, and its possible mechanisms. METHODS: The PD mouse model was established via injecting 1-methyl-4-phenyl-1, 2, 3, 6- tetrahydropyridine (MPTP) and the PD cell model was established via inducing the MN9D cell line with 1-methyl-4-pehnyl-pyridine (MPP+). The behavioral testing of PD model mice was tested after AS-IV treatment and PD-related lincRNAs expression were detected by qRT-PCR. After treatment of PD model cells with AS-IV, lincRNA-p21 expression was detected by qRT-PCR, and cell viability and apoptosis were detected by MTT assay and flow cytometry, respectively. The binding of lincRNA-p21 to C/EBP-homologous (CHOP) protein was investigated by RNA immunoprecipitation and RNA pull-down, and the effect of lincRNA-p21 on the ubiquitination of CHOP protein was examined by ubiquitination assay. The role of lincRNA-p21 in PD model was studied by cell transfection. RESULTS: In PD mice, AS-IV can improve the behavior of mice and significantly inhibit expression of lincRNA-p21. Similarly, AS-IV can obviously restrain the expression of lincRNA-p21 in PD cells, and obviously elevated cell viability and restrained apoptosis. LincRNA-p21 is able to bind to CHOP protein. Further studies showed that restraint of lincRNA-p21 expression can facilitate ubiquitination of CHOP and accelerate its protein degradation. In AS-IV-treated PD model cells, overexpression of lincRNA-p21 lessened cell viability and facilitated apoptosis, whereas low expression of CHOP reversed this result. CONCLUSION: In this study, we found that AS-IV can lessen the expression of CHOP protein by restraining the expression of lincRNA-p21 in the PD model, thereby inhibiting neuronal apoptosis.

Effects of PQ's cytotoxicity on secretory vesicles in astroglia: Expression alternation of secretogranin II and its potential interaction with intracellular factors.

It has been extensively characterized that paraquat (PQ) selectively targets to the substantia nigra and exerts neurotoxic actions on dopaminergic neurons. However, a little knowledge is available about astroglia in PQ exposure, especially its complex secretory machinery. To explore this point, we built up a PQ-induced model in cultural U118 astrocyte. Since the granin family is considered as a master regulator of cargo sorting and large dense core vesicles (LDCVs) biogenesis in the regulated secretory pathway of nervous and neuroendocrine cells, the current study focused on one member, secretogranin II (SCG2) and investigated its alternation and potential relationship with other astrocyte-derived factors under PQ insult. We found that PQ upregulated SCG2 expression on both RNA and protein levels and stimulated the mRNA expression of neurotrophic factors, cytokines and glutamine synthetase (GS) simultaneously. RNAi knockdown of SCG2 did not rescue the cell cycle arrest induced by PQ but affected expressions of IL-6 and GS on mRNA and protein levels. Further studies on subcellular location showed that SCG2-positive secretory granules were partially colocalized with IL-6 but not GS in PQ exposure astrocyte. Taken together, our findings indicate that the expression alternation of SCG2 under astroglial activation by PQ may be necessary compensation for cargo sorting and LDCV biogenesis. The involvement of the IL-6 and GS suggests that the SCG2 may potentially regulate inflammatory factors and excitatory neurotransmitter to the cytotoxicity of PQ on astroglia.

Development of ZnO-based nanorod arrays as scintillator layer for ultrafast and high-spatial-resolution X-ray imaging system.

Under excitation of high-energy and low-flux density of X-ray beam, a 1-µm system spatial resolution was initially achieved by using an 18-µm thickness ZnO nanorod array as the scintillator layer in X-ray imaging beamline at Shanghai Synchrotron Radiation Facility. The decay time measurements indicated the ultraviolet and visible emissions of the arrays were subnanosecond and nanosecond, respectively. Through hydrogen annealing treatment, the ultraviolet luminescence was intensively enhanced and the visible luminescence was remarkably suppressed simultaneously. In conclusion, it can be determined that the ZnO-based nanorod arrays are the decent candidates for applications in ultrafast and high-spatial-resolution X-ray imaging systems.

High-Resolution Melting Analysis as a Developed Method for Genotyping the PD Susceptibility Loci in LRRK2 Gene.

BACKGROUND: Single-nucleotide polymorphisms (SNPs) have been reported as a highly relevant point for the mechanisms of Parkinson's disease (PD). The invention of saturating dye makes it possible to identify heteroduplex DNA without redistribution during melting, which allows using high-resolution melting (HRM) to detect SNPs. However, the HRM analysis for detection of those SNPs associated with PD was rarely applied. METHODS: Two SNPs, G2385R and R1628P, located in leucine-rich repeat kinase 2 (LRRK2) gene were individually and multiplexedly genotyped using HRM analysis. The sequence variant observed in unexpected HRM curves was confirmed by DNA sequencing. RESULTS: HRM analysis identified successfully all genotypes both on R1628P and G2385R loci. The unexpected HRM curves appeared in R1628P amplicon generated from combinations of R1628P and rs11176013 loci. A multiplexed HRM assay that genotyped R1628P, rs11176013, and G2385R loci was efficiently established. CONCLUSIONS: The present HRM assay is a reliable and rapid method for genotyping R1628P and G2385R loci in LRRK2 gene, and multiplex HRM analysis results in high throughput and has the potential to facilitate a wide range of genotyping studies on PD susceptibility genes.

Menthol-Modified Quercetin Liposomes with Brain-Targeting Function for the Treatment of Senescent Alzheimer's Disease.

Oxidative stress and neuroinflammation in the aging brain are correlated with the development of neurodegenerative diseases, such as Alzheimer's disease (AD). The blood-brain barrier (BBB) poses a significant challenge to the effective delivery of therapeutics for AD. Prior research has demonstrated that menthol (Men) can augment the permeability of the BBB. Consequently, in the current study, we modified Men on the surface of liposomes to construct menthol-modified quercetin liposomes (Men-Qu-Lips), designed to cross the BBB and enhance quercetin (Qu) concentration in the brain for improved therapeutic efficacy. The experimental findings indicate that Men-Qu-Lips exhibited good encapsulation efficiency and stability, successfully crossed the BBB, improved oxidative stress and neuroinflammation in the brains of aged mice, protected neurons, and enhanced their learning and memory abilities.

Borneol-Modified Schisandrin B Micelles Cross the Blood-Brain Barrier To Treat Alzheimer's Disease in Aged Mice.

Objective: Schisandrin B (Sch B) is a bioactive dibenzocyclooctadiene derizative that is prevalent in the fruit of Schisandra chinensis. Numerous studies have demonstrated that Sch B has a neuroprotective action by reducing oxidative stress and effectively preventing inflammation. It follows that Sch B is a potential treatment for Alzheimer's disease (AD). However, the drug's solubility, bioavailability, and lower permeability of the blood-brain barrier (BBB) can all reduce its efficacy during the therapy process. Therefore, this study constructed borneol-modified schisandrin B micelles (Bor-Sch B-Ms), which increase brain targeting by accurately delivering medications to the brain, effectively improving bioavailability. High therapeutic efficacy has been achieved at the pathological site. Methods: Bor-Sch B-Ms were prepared using the thin film dispersion approach in this article. On the one hand, to observe the targeting effect of borneol, we constructed a blood-brain barrier (BBB) model in vitro and studied the ability of micelles to cross the BBB. On the other hand, the distribution of micelle drugs and their related pharmacological effects on neuroinflammation, oxidative stress, and neuronal damage were studied through in vivo administration in mice. Results: In vitro studies have demonstrated that the drug uptake of bEnd.3 cells was increased by the borneol alteration on the surface of the nano micelles, implying that Bor-Sch B-Ms can promote the therapeutic effect of N2a cells. This could result in more medicines entering the BBB. In addition, in vivo studies revealed that the distribution and circulation time of medications in the brain tissue were significantly higher than those in other groups, making it more suitable for the treatment of central nervous system diseases. Conclusion: As a novel nanodrug delivery system, borneol modified schisandrin B micelles have promising research prospects in the treatment of Alzheimer's disease.

Mixotrophic aerobic denitrification facilitated by denitrifying bacterial-fungal communities assisted with iron in micro-polluted water: Performance, metabolic activity, functional genes abundance, and community co-occurrence.

Low-dosage nitrate pollutants can contribute to eutrophication in surface water bodies, such as lakes and reservoirs. This study employed assembled denitrifying bacterial-fungal communities as bio-denitrifiers, in combination with zero-valent iron (ZVI), to treat micro-polluted water. Immobilized bacterial-fungal mixed communities (IBFMC) reactors demonstrated their ability to reduce nitrate and organic carbon by over 43.2 % and 53.7 %, respectively. Compared to IBFMC reactors, IBFMC combined with ZVI (IBFMC@ZVI) reactors exhibited enhanced removal efficiencies for nitrate and organic carbon, reaching the highest of 31.55 % and 17.66 %, respectively. The presence of ZVI in the IBFMC@ZVI reactors stimulated various aspects of microbial activity, including the metabolic processes, electron transfer system activities, abundance of functional genes and enzymes, and diversity and richness of microbial communities. The contents of adenosine triphosphate and electron transfer system activities enhanced more than 5.6 and 1.43 folds in the IBFMC@ZVI reactors compared with IBFMC reactors. Furthermore, significant improvement of crucial genes and enzyme denitrification chains was observed in the IBFMC@ZVI reactors. Iron played a central role in enhancing microbial diversity and activity, and promoting the supply, and transfer of inorganic electron donors. This study presents an innovative approach for applying denitrifying bacterial-fungal communities combined with iron enhancing efficient denitrification in micro-polluted water.

Association of five SNPs at the PARK16 locus as a susceptibility locus with Parkinson's disease for forensic application.

To investigate the association of five SNPs (rs823083, rs708723, rs4951261, rs823076 and rs16856110) at the PARK16 locus with Parkinson's disease (PD), and to potentiate its forensic application. The genomic DNAs of 215 PD patients and 212 matched controls from the northern Han Chinese population were amplified in two independent PCR systems and subsequently genotyped by digestion with the three endonucleases (Hinf I, Nco I and Msp I ). The genetic parameters and association studies were carried out with SPSS 13.0, Haploview version 4.2 and PLINK 1.07 softwares. We detected accurately all genotypes in the five SNPs with multiplex PCR-RFLP and mismatched multiplex PCR-RFLP techniques. The genotypes of four SNPs, except for rs823083, were in Hardy-Weinberg equilibrium. The four SNPs, rs16856110, rs4951261, rs708723 and rs823076, which were in linkage equilibrium, should not be associated with PD (P-values ranging from 0.077 to 0.544). The SNPs investigated at the PARK16 locus were not found to be involved in PD-associated blocks in the northern Han Chinese population. The allele distributions of rs708723, rs4951261, rs823076 and rs16856110 in the northern Han Chinese population can be highly polymorphic, which can be applied to genetic analysis and forensic practices.

Density and row spacing of short-season cotton suitable for machine picking in the cotton region of Yellow River Basin.

To determine the suitable planting density and row spacing of short-season cotton suitable for machine picking in the Yellow River Basin of China, we conducted a two-year field experiment in Dezhou during 2018-2019. The experiment followed a split-plot design, with planting density (82500 plants·hm-2 and 112500 plants·hm-2) as the main plots and row spacing (equal row spacing of 76 cm, wide-narrow row spacing of 66 cm+10 cm, equal row spacing of 60 cm) as the subplots. We examined the effects of planting density and row spacing on growth and development, canopy structure, seed cotton yield and fiber quality of short-season cotton. The results showed that plant height and LAI under high density treatment were significantly greater than those under low density treatment. The transmittance of the bottom layer was significantly lower than under low density treatment. Plant height under 76 cm equal row spacing was significantly higher than that under 60 cm equal row spacing, while that under wide-narrow row spacing (66 cm +10 cm) was significantly smaller than that under 60 cm equal row spacing in peak bolling stage. The effects of row spacing on LAI varied between the two years, densities, and growth stages. On the whole, the LAI under the wide-narrow row spacing (66 cm+10 cm) was higher, with the curve declining gently after the peak, and it was higher than that in the two cases of equal row spacing in the harvest time. The change in transmittance of the bottom layer presented the opposite trend. Density, row spacing, and their interaction had significant effects on seed cotton yield and its components. In both years, seed cotton yield was the highest (3832 kg·hm-2 in 2018, 3235 kg·hm-2 in 2019) under wide-narrow row spacing (66 cm+10 cm), and it was more stable at high densities. Fiber quality was less affected by density and row spacing. To sum up, the optimal density and row spacing of short-season cotton were as follows: density with 112500 plants·hm-2 and wide-narrow row spacing (66 cm+10 cm).

Dysregulated expression of secretogranin III is involved in neurotoxin-induced dopaminergic neuron apoptosis.

The neurotoxins paraquat (PQ) and dopamine (DA or 6-OHDA) cause apoptosis of dopaminergic neurons in the substantia nigra pars compacta (SNpc), reproducing an important pathological feature of Parkinson's disease (PD). Secretogranin III (SCG3), a member of the multifunctional granin family, plays a key role in neurotransmitter storage and transport and in secretory granule biogenesis, which involves the uptake of exogenous toxins and endogenous "toxins" in neuroendocrine cells. However, the molecular mechanisms of neurotoxin-induced apoptosis in dopaminergic neurons and the role of SCG3-associated signaling pathways in neuroendocrine regulation are unclear. To address this, we used PQ- and DA-induced apoptosis in SH-SY5Y human dopaminergic cells as an in vitro model to investigate the association between SCG3 expression level and apoptosis. SCG3 was highly expressed in SH-SY5Y cells, and SCG3 mRNA and protein levels were dramatically decreased after PQ treatment. Apoptosis induced by PQ is associated with caspase activation and decreased SCG3 expression, and restoration of SCG3 expression is observed after treatment with caspase inhibitors. Overexpressed SCG3 in nonneuronal cells and endogenous SCG3 in SH-SY5Y cells are cleaved into specific fragments by recombinant caspase-3 and -7, but the fragments were not detected in PQ-treated SH-SY5Y cells. Therefore, SCG3 may be involved in apoptosis signal transduction as a caspase substrate, leading to loss of its original biological functions. In addition, SCG3 may be a pivotal component of the neuroendocrine pathway and play an important role in neuronal communication and neurotransmitter release, possibly representing a new potential target in the course of PD pathogenesis.

[Distribution specificity of human fucosyltransferase 5 and its expression and localization in spermatids].

OBJECTIVE: To investigate distribution specificity of human fucosyltransferase 5 (FUT5) as well as its expression and localization in spermatids. METHODS: Human semen, vaginal swab, saliva and venous blood from healthy individuals were collected. The spermatids were isolated and the spermatid membrane protein was then extracted. Expression levels of FUT5 from human spermatid membrane, seminal plasma, vaginal fluid, saliva and serum were detected by immunoblotting technique. The expression and localization of FUT5 in spermatids were analyzed by immunofluorescent method. RESULTS: Immunoblotting technique showed that FUT5 was expressed on spermatid membranes and in serum, but not in seminal plasma, vaginal fluid and saliva. The expressed FUT5 on spermatids was mostly localized on head of spermatids by fluorescent microscopy, suggesting that there was certain amount of FUT5 on human spermatid membrane, and the spermatids might be isolated from mixed stains with vaginal fluid by antigen-antibody reaction. CONCLUSION: Human FUT5 shows a characteristic distribution specificity, and this feature may be used for identification of mixed stain involved in criminal sexual offence in future forensic practice.

The Origin of Mo2C Films for Surface-Enhanced Raman Scattering Analysis: Electromagnetic or Chemical Enhancement?

The relatively weak Raman enhanced factors of semiconductor-based substrate limit its further application in surface-enhanced Raman scattering (SERS). Here, a kind of two-dimensional (2D) semimetal material, molybdenum carbide (Mo2C) film, is prepared via a chemical vapor deposition (CVD) method, and the origin of SERS is investigated for the first time. The detection limits of the prepared Mo2C films for crystal violet (CV) and rhodamine 6G (R6G) molecules are low at 10-6 M and 10-8 M, respectively. Our detailed theoretical analysis, based on density functional theory and the finite element method, demonstrates that the enhancement of the 2D Mo2C film is indeed CM in nature rather than the EM effects. Besides, the basic doping strategies are proposed to further optimize the SERS sensitivity of Mo2C for Fermi level regulation. We believe this work will provide a helpful guide for developing a highly sensitive semimetal SERS substrate.

[The genetic diversity in the full coding region of human FUT5 gene in a Chinese Han population].

OBJECTIVE: To reveal the sequence variations of the full coding region of the human alpha (1,beta/1,4) fucosyltransferase 5 gene (FUT5) in a Chinese Han population. METHODS: The whole coding region of the FUT5 gene was amplified and sequenced in a total of 30 unrelated Chinese Han individuals. The PCR products containing the nucleotide variants observed in the study were subcloned into plasmid pcDNA to determine all potential haplotypes in the investigated population. Genetic polymorphisms of C560T (rs778970) and C484A loci were further analyzed by polymerase chain reaction-restriction fragment length polymorphism(PCR-RLFP) method. RESULTS: In addition to seven previously reported base substitutions, two novel polymorphisms, namely C484A (Leu162Met) and T684C, were found in the coding region of the FUT5 gene in the 30 individuals. Seven haplotypes were identified by subcloning the variants into plasmid and subsequent DNA sequencing. The allele frequencies in the rs778970 locus in 160 Chinese Han individuals was 0.3031 for 560C and 0.6969 for 560T, while no polymorphism was detected in the C484A locus. CONCLUSION: The sequence of the coding region in the human FUT5 gene demonstrated high genetic diversity, and the allelic distribution of the rs778970 locus in the Chinese populations is polymorphic.