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Ovule initiation is a key step that strongly influences ovule number and seed yield. Notably, mutants with enhanced brassinosteroid (BR) and cytokinin (CK) signaling produce more ovules and have a higher seed number per silique (SNS) than wild-type plants. Here, we crossed BR- and CK-related mutants to test whether these phytohormones function together in ovule initiation. We determined that simultaneously enhancing BR and CK contents led to higher ovule and seed numbers than enhancing BR or CK separately, and BR and CK enhanced each other. Further, the BR-response transcription factor BZR1 directly interacted with the CK-response transcription factor ARABIDOPSIS RESPONSE REGULATOR1 (ARR1). Treatments with BR or BR plus CK strengthened this interaction and subsequent ARR1 targeting and induction of downstream genes to promote ovule initiation. Enhanced CK signaling partially rescued the reduced SNS phenotype of BR-deficient/insensitive mutants whereas enhanced BR signaling failed to rescue the low SNS of CK-deficient mutants, suggesting that BR regulates ovule initiation and SNS through CK-mediated and CK-independent pathways. Our study thus reveals that interaction between BR and CK promotes ovule initiation and increases seed number, providing important clues for increasing the seed yield of dicot crops. This article is protected by copyright. All rights reserved.

Conventional assays for identifying polymorphism of aldehyde dehydrogenase 2 (ALDH2) gene (rs671) are based on electrophoresis, fluorescence-labeled probes or sequencing, which are laborious and expensive. Herein, we proposed a visualized detection of ALDH2 genotype by PCR-based serial invasive reaction coupled with gold nanoparticle probe (GNP) assembling, in which target DNAs were firstly amplified by PCR, and then the alleles on the amplicons were identified by serial invasive reaction, and finally the genotyping results could be read out with naked eyes by observing the color changes caused by GNP assembling. If the allele-specific invasive probe matched the target sequence, the hairpin probe could be cleaved into two parts by Flap endonuclease 1 (FEN1). As a result, the GNPs could not be aggregated by the hairpin probe, keeping the solution red. Otherwise, the intact hairpin probe caused the aggregation of GNPs, leading to the color change from red to purple or clear. Therefore, the genotyping result could be read out with naked eyes by observing the color changes of the reaction. As low as 80 pg of genomic DNA could be accurately genotyped, and the genotyping results of 207 clinical samples were consistent with that of pyrosequencing, indicating that the proposed method has great potential in genotyping of personalized medicine-related single nucleotide polymorphism.

Previous studies have shown that nicotine could impair the germ cell cyst breakdown and the primordial follicle assembly by autophagy. In this paper, we discovered that luteinizing hormone (LH) and follicle-stimulating hormone (FSH) could counteract the damage caused by nicotine of mouse germ cell cyst breakdown. The neonatal mice were separately intraperitoneally injected with nicotine, nicotine plus LH, nicotine plus FSH, and saline (control) for 4 days. Compared with the nicotine group, the quality of oocytes and the number of follicles were remarkably increased in the nicotine plus LH group or nicotine plus FSH group. LH and FSH could alleviate nicotine-induced oocyte autophagy by different pathways. LH reduced the nicotine-induced autophagy by restoring the phosphorylation level of adenosine 5′-monophosphate-activated protein kinase α-1, while FSH by downregulating the phosphorylation level of Forkhead box class O 1. In addition, in a subsequent study of 6-week mice in different treated groups, we found that LH and FSH supplementation significantly improved normal maturation rates, fertilization rates, and embryo’s developmental potential of oocytes in oocytes exposed to nicotine. Taken together, these results suggested that LH and FSH could counteract the damage caused by nicotine and finally ensure normal germ cell cyst breakdown and early embryo development.

Two types of tonoplast proton pumps, H+ -pyrophosphatase (V-PPase) and the H+ -ATPase (V-ATPase), establish the proton gradient that powers molecular traffic across the tonoplast thereby facilitating turgor regulation and nutrient homeostasis. However, how proton pumps regulate development remains unclear. In this study, we investigated the function of two types of proton pumps in Arabidopsis embryo development and pattern formation. While disruption of either V-PPase or V-ATPase had no obvious effect on plant embryo development, knocking out both resulted in severe defects in embryo pattern formation from the early stage. While the first division in wild-type zygote was asymmetrical, a nearly symmetrical division occurred in the mutant, followed by abnormal pattern formation at all stages of embryo development. The embryonic defects were accompanied by dramatic differences in vacuole morphology and distribution, as well as disturbed localisation of PIN1. The development of mutant cotyledons and root, and the auxin response of mutant seedlings supported the hypothesis that mutants lacking tonoplast proton pumps were defective in auxin transport and distribution. Taking together, we proposed that two tonoplast proton pumps are required for vacuole morphology and PIN1 localisation, thereby controlling vacuole and auxin-related developmental processes in Arabidopsis embryos and seedlings.

Caseinate was crosslinked by horseradish peroxidase (HRP) or microbial transglutaminase (TGase) and mixed with kaempferol and quercetin at 293–313 K (i.e. 20–40 °C), respectively. Generally, these two polyphenols dose-dependently induced fluorescent quenching in caseinate or its crosslinked products via a static mechanism, while enzymatic crosslinking endowed caseinate with higher affinity for the polyphenols with increased apparent binding constants [(9.94–168.77) × 105 versus (4.92–6.53) × 105 L/mol], unchanged binding site number and slightly shortened binding distance. To form protein–polyphenol complexes, hydrophobic force was the main driving force for the HRP-crosslinked caseinate and unreacted caseinate, while hydrogen-bonds and van der Waals force were the main driving forces for the TGase-crosslinked caseinate. Overall, quercetin was more potent than kaempferol to bind to the proteins, while TGase-mediated caseinate crosslinking induced the highest affinity to the polyphenols with the largest ΔG decrease. Thus, two types of crosslinking impacted the driving forces, apparent binding constant and thermodynamic indices of caseinate-polyphenol interaction.

Objective. To observe the protective effect of AC-YVAD-CMK on sepsis-induced acute kidney injury in mice and to explore its possible mechanisms primarily. Methods. Eighteen male C57BL/6 mice were randomly divided into sham-operated group (Control), cecal ligation and puncture group (CLP), and CLP model treated with AC-YVAD-CMK group (AC-YVAD-CMK) ( n = 6 in each group). Mice were sacrificed at 24 h after operation, and blood and kidney tissue samples were collected for analyses. Histologic changes were determined microscopically following HE staining. The expression of Ly-6B and CD68 was investigated using immunohistochemistry. Serum concentrations of creatinine (sCR) and blood urea nitrogen (BUN) were measured. Serum levels of interleukin-1β (IL-1β), interleukin-18 (IL-18), TNF-α, and interleukin-6 (IL-6) were determined by ELISA. The expressions of Caspas-1, NLRP-1, IL-1β, and IL-18 in renal tissues were investigated using Western blot. Immunofluorescence staining was used to detect the expression of GSDMD protein in renal tissues. Results. AC-YVAD-CMK treatment significantly alleviates sepsis-induced acute kidney injury, with decreased histological injury in renal tissues, suppresses the accumulation of neutrophils and macrophages in renal tissues, and decreased sCR and BUN level ( P < 0.05 ). Attenuation of sepsis-induced acute kidney injury was due to the prohibited production of inflammatory cytokines and decrease expression of Caspas-1, NLRP-1, IL-1β, and IL-18 in renal tissues. In addition, AC-YVAD-CMK treatment significantly reduced the expression of GSDMD in renal tissues compared to those observed in controls ( P < 0.05 ). Conclusions. We demonstrated a marked renoprotective effect of caspase-1-inhibitor AC-YVAD-CMK in a rat model of sepsis by inhibition of pyroptosis.

Plant ovule initiation determines the maximum of ovule number and has a great impact on the seed number per fruit. The detailed processes of ovule initiation have not been accurately described, although two connected processes, gynoecium and ovule development, have been investigated. Here, we report that ovules initiate asynchronously. The first group of ovule primordia grows out, the placenta elongates, the boundaries of existing ovules enlarge and a new group of primordia initiates from the boundaries. The expression pattern of different marker genes during ovule development illustrates that this asynchronicity continues throughout whole ovule development. PIN-FORMED1 polar distribution and auxin response maxima correlate with ovule primordia asynchronous initiation. We have established computational modeling to show how auxin dynamics influence ovule primordia initiation. Brassinosteroid signaling positively regulates ovule number by promoting placentae size and ovule primordia initiation through strengthening auxin response. Transcriptomic analysis demonstrates numerous known regulators of ovule development and hormone signaling, and many new genes are identified that are involved in ovule development. Taken together, our results illustrate that the ovule primordia initiate asynchronously and the hormone signals are involved in the asynchrony., Summary: Ovule primordia initiation, which determines the maximum ovule number and subsequent seed number in Arabidopsis, is asynchronous and is regulated by PIN1 polar distribution and the auxin response.

Consumption of functional juice is becoming increasingly popular. This study aimed to evaluate the effect of probiotic fermentation with Bacillus sp. DU-106; Lactobacillus planturum Lp-43 and Lactobacillus rhamnosus Lr-156 on the biochemical and functional characteristics, antioxidant activities and storage stability of Dendrobium officinale and banana (DOB) juice. The cell levels of the lactic acid bacteria reached near 9 log copies/mL after fermentation at 32 °C for 36 h and could keep in this level after storage at 4 °C for 28 days. After fermentation, total acidity, flavonoids and polysaccharide contents of DOB juice increased, while pH, dissolved oxygen, nitrite, nitrate, vitamin C, β-carotene, sugar contents and antioxidant capacity slightly decreased. Compared with nonfermented DOB juice, polyphenol oxidase (PPO) and peroxidase (POD) activities of fermented DOB decreased significantly, but the color value and the content of total phenols and vitamin C decreased slightly in fermented DOB juice during storage. Overall, the probiotic fermentation with selected strains could improve the quality the DOB juice, enhance antioxidant capacity and storage stability, and destroy accumulation of nitrite and nitrate during storage. Findings of this study would help in the development of beneficial beverages in industrial production.

Fluorescent cellulose nanocrystals (fCNCs) have shown a great potential as optical probe for the applications of bioimaging or metal ion detection. In this work, by a controllable esterification strategy, the cellulose nanocrystal (CNC) surface was modified with ethylenediaminetetraacetic dianhydride (EDTAD) to achieve highly carboxylation degree, and, meanwhile, keep surface integration and crystalline structure in comparison with the TEMPO oxidation method. Then, the controllability of carboxylation degree was applied to produce a series of fCNCs with various conjugating densities of fluorescent 7-amino-4-methylcoumarin (AMC). The steric effect of AMCs on the fCNC surface could inhibit self-quenching, resulting in a more stable fluorescence intensity independent upon the change of fCNC concentration and a relatively high quantum efficiency in the solid state. Moreover, the fluorescence signals of fCNC can be selectively affected by Cu2+, and even high Cu2+ concentration resulted in the visualized color change from blue to purple under ultraviolet radiation. Hence, two linear correlations with the Cu2+ concentration, i.e. the fluorescence attenuation ratio at 390 nm in 0.5–16 ppm of Cu2+ concentration and the fluorescence intensity ratio of 440 nm versus 390 nm in 16–160 ppm of Cu2+ concentration, contributed to a potential of quantitative Cu2+ detection. Especially, the on–off behavior of the fCNC fluorescence at the critical Cu2+ concentration of 0.5 ppm was well consistent with the requirement of the Guideline of Drinking-Water Quality (GDWQ) administrated by World Health Organization (WHO), and hence might be used to rapid and visualized evaluation of drinking water quality. This work provides a new fluorescent nanomaterial that can be used in metal ion detection. Furthermore, the nontoxicity, biodegradability and environment-friendliness of cellulose nanocrystals might also contribute to the additional advantages for the application of environmental surveillance.

The main determinant of crop yield is seed yield. In Arabidopsi, many of the genes that regulate seed number are involved in gametophyte and zygote development, and their overexpression cannot increase seed number. However, several mutants with enhanced brassinosteroid (BR) and cytokinin (CK) signals show increased seed number per silique (SNS). Here, we studied the crosstalk between BR and CK signals in regulating SNS through crossing BR- and CK-related mutants. Compared with the mutants ckx3 ckx5 and bzr1-1D , the triple mutant ckx3 ckx5 bzr1-1D with enhanced BR and CK signals formed elongated placentae and showed increased ovule initiation and SNS, indicating that BR and CK synergistically up-regulate SNS. Although BR enhanced the CK signal and CK enhanced the BR signal, while CK partially rescued the phenotypes of BR deficient- and -insensitive mutants, BR could not rescue the phenotypes of CK-deficient mutants. This suggested that CK functions downstream of BR in regulating SNS and that BR regulates SNS through CK-mediated or CK-independent pathways. Comparative transcriptome analyses of ckx3 ckx5 , bzr1-1D , and ckx3 ckx5 bzr1-1D identified known and new genes involved in ovule initiation. The BR-induced transcription factor BZR1 was found to directly interact with the B-type regulator of CK, ARR1, and this interaction enhanced the ability of ARR1 to target and induce genes related to ovule development. Our results demonstrate that BR and CK synergistically increase SNS through co-regulating downstream genes involved in ovule identity and initiation. The genes involved in this process have potential applications in enhancing crop yield.

Brassinosteroid (BR) is a family of bioactive steroid hormones that plays vital roles in plant growth and development. The BR-mediated regulation of plant growth and architecture has been well studied. However, relatively few studies have investigated the BR-related regulation of reproductive development because of the difficulties in excluding non-specific regulation and secondary responses from severe vegetative phenotypes and poor nutritional status. Furthermore, differentially regulating the BR signal in vegetative and reproductive organs is problematic. Thus, establishing a method for modulating the BR signal only in reproductive organs or during reproductive developmental stages will be beneficial. Additionally, the utility of BR applications for crop production is limited because of deleterious side-effects, including the associated decrease in the planting density and lodging resistance. Moreover, enhancing the BR signal may lead to feedback inhibition. In this study, we developed a transformation system for modulating the BR signal differentially during reproductive and vegetative developmental stages. This system involves transformations with different combinations of a reproductive tissue-specific promoter, coding sequences that increase or decrease the BR signal, and various genotypic backgrounds with enhanced or decreased BR signals. The enhanced BR signal generated in transformants was targeted to reproductive organs without affecting vegetative organs. This system may be useful for studying the BR-specific regulation of plant reproductive development and shows promise for optimizing seed yield.

Assessing the impact of plantation on microbial respiration (MR) is vitally important to understand the interactions between belowground metabolism and land use change. In this study, cumulative MR was determined by alkali absorption method in 1, 3, 7, 14, 21, 28, 35, 42, 49, and 56 days from the soil in a representative plantations in the subtropical region of China. The treatment of plantations contained no plant (CK), orange trees (Citrus reticulata)+Bahia grass (Paspalum notatum) (GB), orange trees (C. reticulata)+Bahia grass (P. notatum)+soybean (Giycine max (L.) Merrill) (GBH). Results showed that plantation had significant effects on microbial respiration and the responses of microbial respiration to plantation from different soil layers and topographies were different: in 0–20 cm in uphill: GB>GBH>CK; in 20–40 cm in uphill: GBH>CK>GB; in 0–20 cm in downhill: GBH>CK>GB; in 20–40 cm in downhill: GB>CK>GBH. Furthermore, plantation also altered the relationships between MR and soil properties. In CK, microbial respiration was positively correlated with NH4+ and soil total N, and negatively correlated with soil moisture, pH, NO3−, and microbial biomass carbon (MBC). In GB, microbial respiration under GB significantly negatively correlated with dissolved organic carbon (DOC). In GBH, microbial respiration under GBH was positively correlated with NH4+, MBC, total soil carbon (TC), and total soil nitrogen (TN), and negatively correlated with soil moisture (SM), pH, NO3−, and DOC. The underlying mechanisms could be attributed to soil heterogeneity and the effects of plantation on soil properties. Our results also showed that plantation significantly increased soil C storage, which suggested plantation is a key measure to enhance soil C sequestration and mitigate global CO2 emission, especially for the soil with low initial soil carbon content or bared soil.

Vitamin D receptor (VDR) polymorphisms have been inconsistently investigated in multiple sclerosis (MS). However, published studies demonstrated differences concerning design and effect size. A meta-analysis is necessary to determine the magnitude of the association between VDR polymorphisms and MS risk. The aim of the current study was to quantify the magnitude of the association between BsmI, FokI, ApaI, and TaqI VDR polymorphisms and MS risk. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a systematic search and meta-analysis of the VDR gene polymorphisms and the risk of MS. The pooled odds ratios (OR) and 95% confidence interval (CI) were calculated by using Stata Version 11.0 with dominant and recessive models and allele analyses. A total of 4013 cases and 4218 controls in 24 case-control studies were included in the meta-analyses. The results did not indicate an association between any of the VDR polymorphisms and the risk of MS among overall populations, Asians, and Caucasians. However, our subgroup analysis suggests that the A allele was associated with MS risk in Asian populations (P = 0.005, OR = 1.267, 95% CI 1.074-1.496). Interestingly, the sensitivity analysis excluding studies with controls not in HWE showed insignificant association between the A allele and MS risk (P = 0.211), which was different from those in the non-sensitivity analysis. Our preliminary results indicate the VDR gene ApaI, BsmI, FokI, and TaqI polymorphisms may not be associated with elevated MS risk among overall populations. But ApaI polymorphism may confer different susceptibility to MS among different populations, and more well-designed studies with a large sample size are still needed to validate our results.

Thermal diffussion (TD) is a method of coating steels to improve the service life of materials and tools. With this process, high hardness of vanadium carbide coating is formed on the surface of materialsso that its wear, bite, corrosion resistance can be greatly improved. Since thereare still several problems remaining to be solved, this technology is still not widely used in our country and that limit the popularity of the salt bath technology. In this paper, these problems and their causes are discussed based on experiments, and several solutions are presented to hopefully provide suggestions for industrial production.

Astragalus mongholicus is a famous traditional Chinese medicinal herb because of its human health benefits and bioactive compounds. Pulverization process directly affects quality and dissolution of bioactive compounds of A. mongholicus. In the present study, liquid nitrogen was introduced to pulverization process of A. mongholicus. The pulverization with addition of liquid nitrogen (LNP) effectively retained powder color, crushed tissue fiber, and reduced hardness of A. mongholicus. Furthermore, LNP significantly improved elasticity and solubility of the powder, as well as soluble solid contents. In addition, extraction yield of polysaccharides, characteristic bioactive compounds in A. mongholicus, was increased by 10.5 % by combination of LNP and Tween-80 enzyme extraction. These results suggest that LNP can be a promising technology for preparation of A. mongholicus powder. The information will also contribute to improvement of manufacturing technology of Chinese medicinal herb.

Spherical LiMnPO4/C composite micro-particles with different carbon content were prepared by spray drying followed by heat treatment in the range of spray drying temperature from 220°C to 270°C. The structure, morphology and electrochemical performance of the resulting spherical LiMnPO4/C microparticles were characterized by X-ray diffraction, SEM and standard electrochemical techniques. Caron coated LiMnPO4 could be prepared from the as-prepared powders followed by heat treatment at 600°C for 12h in a Ar+10%H2 atmosphere. The sample was identified as olivine structure of LiMnPO4 without any impurity and spherical powders with approximately 3-5μm in primary particles size. Sample which was synthesized at 220°C SD temperature,10% carbon content showed the best electrochemical performance due to its small and homogeneous particle size diffusion, uniform carbon coating.

The invention of plastic film has brought not only convenience but also environmental pollution to people. To use natural vegetable fiber is the mainly approach to solve the problem. In this paper, the waste cotton fiber was used as raw material and the cotton nonwoven sample was made through wet laying process, after strengthened by chitosan, degradable film was prepared. The performances of the film were characterized and analyzed by testing the strength, air permeability, moisture permeability and other indexes. The results showed that chitosan can be used as strengthening agent, the performances of the film strengthened were improved, and it was degradable.

Hollow fiber liquid–liquid phase microextraction followed by high-performance liquid chromatography was employed to research the binding of four furocoumarin compounds (psoralen, oxypeucedanin, imperatorin and isoimperatorin) to bovine serum albumin. The results reveal that the percent of drug–protein binding did not rely on the furocoumarins and protein concentrations, and four furocoumarins scarcely competed for protein binding sites. The protein-binding percents of psoralen, oxypeucedanin, imperatorin and isoimperatorin were 55.1 ± 4.5, 14.4 ± 2.4, 44.1 ± 6.7, and 41.3 ± 3.8%, respectively, the numbers of binding sites were 1.2, 1.6, 0.6 and 0.3, and the binding constants were 1,801, 212, 937 and 4,025 L mol−1, respectively. The proposed new approach is simple, rapid, and effective for the study of the interaction between protein and furocoumarin compounds which is either individual or coexistent with the similar ones.

A kind of chiral azobenzene amphiphile, N -[4-(4-dodecyloxyphenylazo)benzoyl]- l -glutamic acid (C 12 -Azo- l -Glu; as shown in Fig. 1), was synthesized and the self-organization properties on solid substrates were investigated. C 12 -Azo- l -Glu underwent a reversible trans – cis photoisomerization in dilute solution. While the photoisomerization was suppressed on solid substrate because of the H-aggregation, indicating the formation of compact film. When C 12 -Azo- l -Glu was cast from ethanol solution onto the hydrophilic surface of mica, a stable flat-layered structure formed spontaneously in large scale. High-resolution images allowed the identification of the relative orientation of molecular rows in the ordered thin film and the crystal lattice of mica. A molecular packing model of the layered structure was proposed. There was a template effect of mica to the self-organization process. Hydrogen bonding, π–π interaction and the chiral center in the molecule played the important roles in the self-organization process. The cooperative competitive effect between them led to the highly ordered structure.

Soil respiration (Rs) is a major source of carbon emission in terrestrial ecosystems. Despite the fact that the influence of land use practice on Rs has been widely studied, the patterns and drivers on Rs of Citrus reticulata cultivation, a worldwide land use practice are unclear. In this current study, we investigated the influence of long-term cultivation of Citrus reticulata (CO) and of CO intercropped with soybean (CB) on soil nutrients, water availability, and Rs in southern China. Results indicated that after 21 years of cultivation, CO and CB significantly increased total soil carbon (TC), total soil nitrogen (TN), and soil organic matter (OM) at 0–20 cm and 20–40 cm, both at upslope and downslope compared with bare soil (CK). However, soil moisture (SM), dissolved organic carbon (DOC), and microbial biomass carbon (MBC) decreased under CB. In addition, no significant variation was found in soil pH between CK, CO, and CB. Across incubation time (56 days), Rs decreased exponentially with incubation time and CB showed the highest Rs rate irrespective of soil depth or topography. Linear regression further showed TC and TN as the two major factors influencing Rs upslope, while DOC was the dominant factor in regulating Rs downslope. These findings demonstrated that long-term cultivation of citrus significantly changed soil nutrients, water availability, and Rs rate.

An azobenzene derivative 4-hydroxy-3′-trifluoromethyl-azobenzene (FAzoH) was synthesized and the physisorbed monolayers of the molecule at the liquid/solid interface were investigated by scanning tunneling microscopy (STM). The acquired STM images exhibit the molecular packing of the monolayers of FAzoH in trans conformation. Following the UV light (365 nm) induced trans–cis isomerization, stable domains of pure cis isomers have been identified by STM. The results suggest that a strong hydrogen bonds network existing in the monolayer stabilizes the domains of the cis isomer.

The interfacial-dependent self-organization of a chiral amino acid amphiphile is observed by atomic force microscopy (AFM). This chiral amino acid amphiphile possesses an amide group and two carboxyl groups that can form intermolecular hydrogen bonds in different forms, which corresponding to the two energy-minimum states exist in the aggregates of chiral molecules in one enantiomeric form. Three kinds of organizations were induced at different interfaces, which appear as helical aggregates on hydrophobic surface (e.g., highly oriented pyrolytic graphite (HOPG)), molecular flat layer, and superstructure layer on hydrophilic surface (e.g., mica). Moreover, these two energy-minimum states can also coexist in the same layer of the superstructure on an ordered hydrophobic surface made of the linearly aligned hydrocarbon chains. These phenomena experimentally prove the existence of double energy-minimum states in the chiral molecules that are in one enantiomeric form. The results presented here provide insight...

Topography and electric property of the physisorbed monolayer of an azobenzene derivative, 4,4′-dihexyloxy-2-hydroxy-azobenzene (Azo), at the liquid/graphite interface were investigated by scanning tunneling microscopy (STM). The STM observations show that the azobenzene derivative can form an ordered row-like structure at the interface and the periodicity of the row is 3.0 nm, corresponding to the length of the molecule. Electric property of this organic tunnel junction at the liquid/graphite interface was examined by the measurement of the current–voltage (I–V) curve. The I–V curve is asymmetric for positive and negative voltages, indicating the rectifying behavior of the adlayer.

Purple membrane (PM) monolayers were deposited on hydrophilic or hydrophobic silicon substrates through the Langmuir–Blodgett (LB) technique. The photovoltaic features and interfacial charge separation of p-Si/PM/indium tin oxide (ITO) heterostructure were studied by surface photovoltage spectroscopy (SPS). The different photovoltaic response values were obtained due to the nonrandom orientation of PM in the LB films on the hydrophilic versus hydrophobic silicon substrates. The photovoltaic response value versus external potential of the p-Si/cytoplasmic-extracellular/ITO heterostructure showed an obviously rectifying behavior. Compared with the p-Si/ITO heterostructure, the response value of SPS increased more rapidly in the case of the positive external bias.

A polymer containing 3‘-[trifluoromethyl-4,3‘-dibenzoazo] dyes in the side chains has been synthesized, and a monolayer of this polymer has been transferred onto solid substrate by the Langmuir−Blodgett (LB) technique. The reversible processes of photoisomerization of the LB films induced by light are observed by UV−vis absorption spectra, in situ atomic force microscopy, and friction force microscopy. In addition, the physisorbed monolayers of the monomer of the polymer at liquid/solid interface are investigated by scanning tunneling microscopy. The films of the polymer show the reversible change of morphological and friction force responses under alternate UV (365 ± 10 nm) and visible (436 ± 10 nm) irradiation. The films also undergo reversible wettability changes with UV and visible light irradiation, which are directly confirmed by contact angle measurement. The largest photoinduced change of contact angle is 11 ± 1°. The larger value of the contact angles measured corresponds to films mainly composed...

A kind of amino acid amphiphile (N-stearoyl-glutamic acid) was synthesized and used to investigate chiral discrimination at the interface by surface pressure−area (π−A) isotherm measurements and atomic force microscopy (AFM). On the acidified water and aqueous CdCl2 solution subphase at pH = 2, monolayers were built up from the l enantiomer and the racemate of N-stearoyl-glutamic acid. The π−A isotherms indicated that chiral discrimination could be observed on the aqueous CdCl2 solution more obviously than on acidified water. The monolayers of the racemate were transferred onto newly cleaved mica surfaces for AFM investigation. Molecular images obtained on the monolayer prepared from the acidified water subphase gave a two-molecule rectangular unit cell that accommodates only racemates, whereas the mirror images could be obtained on the monolayer prepared from aqueous CdCl2 solution, which indicates chiral discrimination in two dimensions.

An azobenzene derivative [4-(6-oxo-hexacarboxylic acid)-3'-trifluoromethyl-azobenzene] was synthesized and transferred onto a solid substrate by the Langmuir-Blodgett (LB) technique. The films undergo reversible wettability changes upon irradiation with ultraviolet (UV, 365 ± 10 nm) and visible (436 ± 10 nm) light. This property of reversible wettability of the LB film is confirmed directly by contact angle measurement, UV-Vis absorption spectroscopy and atomic force microscopy (AFM). The results suggest that the wettability change is due to a photoinduced surface energy change.

A water-soluble binuclear cobalt phthalocyanine-sulphonate was used to prepare LB films by semi-amphiphilic technique. Atomic force microscopy (AFM) was applied to investigate the surface morphology of C18NH2-OME/bi-CoPc LB multilayer on silicon substrate and surface photovoltage spectra (SPS) was used to study the interfacial charge transfer properties.

Hemin (iron(III) protoporphyrin IX chloride) and mixed hemin/n-octadecylamine (ODA) with the molar ratio of 1:2 were used to investigate the Langmuir monolayer behavior and to prepare the Langmuir−...

Langmuir and Langmuir−Blodgett (LB) films of two kinds of C60 derivatives with the substituents which have methoxycarbonyl (C60(I)) and a carboxylic group (C60(II)) were investigated, respectively. The photovoltaic behaviors and charge-transfer process of their LB films on n-type Si substrates and their powders were studied by surface photovoltage spectra (SPS). For the electronic effect caused by different electron-withdrawing groups, they exhibited different photovoltaic behaviors, and the reverse response values of SPS were obtained when the C60-derivatives powders contact with indium tin oxide substrates. The reason was that the relatively strong electron-withdrawing substituent shifted the molecular orbital levels to lower energy, which caused the opposite surface band bending. When deposited on n-Si substrates, the two kinds of C60-derivative LB films both exhibited the same increment on the direct transition of n-Si. Furthermore, the structural characterization of C60(II) LB film was studied in det...

A kind of water-soluble binuclear cobalt phthalocyaninesulfonate (bi-CoPc) was synthesized and used to prepare Langmuir−Blodgett (LB) films by the semiamphiphilic technique. On the bi-CoPc-containing subphase, monolayers were built up from the mixtures of octadecylamine (C18NH2) and methyl octadecanoate (OME). The surface pressure−area (π−A) isotherms indicated that C18NH2−OME molecules could form well-defined condensed-type monolayers. The monolayers of C18NH2:OME = 1:1 and 1:4 were deposited onto solid substrates (CaF2 and silicon substrates). Small-angle X-ray diffraction (XRD) patterns of C18NH2−OME/bi-CoPc LB multilayers indicated the formation of highly ordered multilayers in the vertical direction. The long spacings of LB multilayers were 5.94 and 5.11 nm for C18NH2:OME = 1:4 and 1:1, respectively. This suggested that in the LB multilayer of C18NH2:OME = 1:4 the hydrocarbon chains stood more vertically than that of 1:1. FTIR spectra confirmed the formation of the supermolecular assembly of C18NH2 a...

Azobenzene-containing liquid crystal, 2-hydroxy-4-hexyloxy-4′-hexyloxy azobenzene (AB), was synthesized and used to produce LB films. The surface pressure vs surface area isotherm showed that the liquid crystal molecules formed a stable multilayer on the water subphase owing to the self-assembly for their much smaller area per molecule with 0.1 nm 2 at π =0 and 0.07 nm 2 at collapse point. This spontaneous behavior was also confirmed by small angle X-ray diffraction for a ‘horizontally once-transferred’ LB film. The ‘vertically multi-transferred’ LB film also exhibited the same ordered layer structure with the long spacing of the multilayer about 2.0 nm. Polarized FTIR spectra were used to measure the orientation of liquid crystal molecules in LB films with a tilt angle of 60° and 48° (corresponding to azobenzene moiety and hydrocarbon chain, respectively), which is well in accordance with the result of X-ray diffraction. The result from UV–vis absorption spectra revealed that the AB molecule formed H-aggregation in LB films.

Three different azobenzene derivatives, namely, 2-(6-methacryloxyhexyloxy)-4-hexyloxy-4‘-hexyloxyazobenzene (A1) and poly{6-[5-hexyloxy-2-(4-hexyloxypheny)azophenyloxy]hexyl methacrylate}x-co-{2-hydroxyethyl methacrylate}y (A2, x = 0.8, y = 0.2), and (A3, x = 0.2, y = 0.8), have been synthesized to study the characterization of Langmuir monolayers at the air−water interface and the aggregation and orientation of Langmuir−Blodgett (LB) films on a solid substrate. The surface pressure−area isotherms showed that they could form well-defined condensed-type monolayers, with A1 and A2 undergoing conformational transition. The monolayers of A1 and A3 could be deposited onto substrate at 20 mN/m at 20 °C with a near unity transfer ratio. The polarized Fourier transform infrared and polarized UV−vis spectra revealed that LB films of A1 and A3 on substrates had in-plane orientation with the long axis of azobenzene moiety exhibiting a large tilt angle (42° and 35°, respectively) with respect to the substrate normal....

Oligomer-polymaleic acid octadecanol esters (PMAO) with different ratios between carboxylic groups and hydrocarbon chains stabilized CdS nanoparticles were produced in the form of reversed micelles. The PMAO-capped CdS nanoparticles were transferred from the air–water interface onto CaF 2 and silicon substrates. Surface pressure–area isotherms gave the information that both the two kinds of pure PMAO and PMAO-capped CdS could form stable monolayers on the water subphase. From the area occupied by average molecular unit (0.24 and 0.11 nm 2 ), it was concluded that the size of two kinds of PMAO-capped CdS nanoparticles was different. The results of UV-vis spectra gave us information that the diameter of CdS nanoparticles could be controlled to less than 2 nm. The measurement of Fourier transform infrared spectroscopy (FTIR) confirmed the formation of CdS. The average tilt angle of hydrocarbon chains revealed by polarized IR spectra was 50 and 60°, respectively. The long spacing of the multilayer of PMAO-capped CdS determined by small angle X-ray diffraction was 6.3 and 4.8 nm, which also maintained the conclusion that the ratio between carboxylic groups and hydrocarbon chains effect the size of reversed micelles.

Summary Superoxide dismutase 1 (Sod1) has been known for nearly half a century for catalysis of superoxide to hydrogen peroxide. Here we report a new Sod1 function in oxidative signaling: in response to elevated endogenous and exogenous reactive oxygen species (ROS), Sod1 rapidly relocates into the nucleus, which is important for maintaining genomic stability. Interestingly, H2O2 is sufficient to promote Sod1 nuclear localization, indicating that it is responding to general ROS rather than Sod1 substrate superoxide. ROS signaling is mediated by Mec1/ATM and its effector Dun1/Cds1 kinase, through Dun1 interaction with Sod1 and regulation of Sod1 by phosphorylation at S60, 99. In the nucleus, Sod1 binds to the promoters and regulates the expression of oxidative resistance and repair genes. Altogether, our study unravels an unorthodox function of Sod1 as a transcription factor and elucidates the regulatory mechanism for its localization.