Quercetin alleviates the toxicity of difenoconazole to the respiratory system of carp by reducing ROS accumulation and maintaining mitochondrial dynamic balance.

Difenoconazole (DFZ) is a fungicidal pesticide extensively employed for the management of fungal diseases in fruits, vegetables, and cereal crops. However, its potential environmental impact cannot be ignored, as DFZ accumulation is able to lead to aquatic environment pollution and harm to non-target organisms. Quercetin (QUE), a flavonoid abundant in fruits and vegetables, possesses antioxidant and anti-inflammatory properties. In this article, carp were exposed to 400 mg/kg QUE and/or 0.3906 mg/L DFZ for 30 d to investigate the effect of QUE on DFZ-induced respiratory toxicity in carp. Research shows that DFZ exposure increases reactive oxygen species (ROS) production in the carp's respiratory system, leading to oxidative stress, inflammation, and damage to gill tissue and tight junction proteins. Further research demonstrates that DFZ induces mitochondrial dynamic imbalance and gill cell apoptosis. Notably, QUE treatment significantly reduces ROS levels, alleviates oxidative stress and inflammation, and mitigates mitochondrial dynamics imbalance and mitochondrial apoptosis. This study emphasizes the profound mechanism of DFZ toxicity to the respiratory system of common carp and the beneficial role of QUE in mitigating DFZ toxicity. These findings contribute to a better understanding of pesticide risk assessment in aquatic systems and provide new insights into strategies to reduce their toxicity.

Understanding FRET in Upconversion Nanoparticle Nucleic Acid Biosensors.

Upconversion nanoparticles (UCNPs) have been frequently applied in Förster resonance energy transfer (FRET) bioanalysis. However, the understanding of how surface coatings, bioconjugation, and dye-surface distance influence FRET biosensing performance has not significantly advanced. Here, we investigated UCNP-to-dye FRET DNA-hybridization assays in H2O and D2O using ∼24 nm large NaYF4:Yb3+,Er3+ UCNPs coated with thin layers of silica (SiO2) or poly(acrylic acid) (PAA). FRET resulted in strong distance-dependent PL intensity changes. However, the PL decay times were not significantly altered because of continuous Yb3+-to-Er3+ energy migration during Er3+-to-dye FRET. Direct bioconjugation of DNA to the thin PAA coating combined with the closest possible dye-surface distance resulted in optimal FRET performance with minor influence from competitive quenching by H2O. The better comprehension of UCNP-to-dye FRET was successfully translated into a microRNA (miR-20a) FRET assay with a limit of detection of 100 fmol in a 80 µL sample volume.

Long non-coding RNA MIR22HG suppresses the chondrogenic differentiation of human adipose-derived stem cells by interacting with CTCF to upregulate CRLF1.

Improved chondrogenic differentiation of mesenchymal stem cells (MSCs) by genetic regulation is a potential method for regenerating articular cartilage. LncRNA MIR22HG has been proven to accelerate osteogenic differentiation, but the regulation mechanism of chondrogenic differentiation is still unclear. Human adipose-derived stem cells (hADSCs) have been widely utilised for bone tissue engineering applications. The present study aimed to examine the effect of MIR22HG on the chondrogenic differentiation of hADSCs. The results confirmed that MIR22HG was downregulated in the process of chondrogenic differentiation. Subsequently, gain- and loss-of-function of MIR22HG experiments showed that the overexpression of MIR22HG suppressed the deposition of cartilage matrix proteoglycans and decreased the expression of cartilage-related markers (e.g. Sox9, ACAN and Col2A1), whereas the knockdown of MIR22HG had the opposite effect. MIR22HG could bind to CTCF (CCCTC-binding factor), and CTCF could bind to the CRLF1 (cytokine receptor-like factor 1) promoter and upregulate CRLF1 gene expression. Besides, inhibition of CRLF1 can reverse the effect of MIR22HG on cell chondrogenic differentiation of hADSCs. Taken together, our outcomes reveal that MIR22HG suppressed chondrogenic differentiation by interaction with CTCF to stabilise CRLF1.

Ferulic acid alleviates carp brain damage and growth inhibition caused by avermectin by modulating the Nrf2/Keap1 and NF-κB signaling pathways.

The increasing concern over environmental pollution caused by the pesticide avermectin used in aquaculture has attracted significant attention. The use of avermectin, a neurotoxic pesticide, in aquatic environments leads to toxic effects on non-target organisms, particularly causing harm to fish. The phenolic compound ferulic acid possesses excellent anti-inflammatory and antioxidant capabilities. This study was conducted by establishing a chronic exposure experiment to avermectin, proposes the use of ferulic acid as a dietary additive to protect the carp brain from damage caused by exposure to avermectin. Furthermore, it investigates the anti-inflammatory and antioxidant effects of ferulic acid in the carp brain under chronic exposure to avermectin. The experimental results demonstrate that ferulic acid can alleviate brain tissue inflammation and oxidative stress by modulating the Nrf2/Keap1 and NF-κB signaling pathways. It protects the carp brain from chronic avermectin-induced damage, preserves the integrity of the carp blood-brain barrier, enhances the levels of feeding factors, and thereby alleviates carp growth inhibition. These findings provide new therapeutic strategies and a theoretical foundation for the sustainable development of carp aquaculture.

[Analysis of ARX gene variant in a child with X-linked lissencephaly with abnormal genitalia].

OBJECTIVE: To explore the clinical characteristics and genetic basis for a child with X-linked lissencephaly with abnormal genitalia (XLAG). METHODS: A child with XLAG who had presented at the Third Affiliated Hospital of Zhengzhou University in May 2021 was selected as the study subject. Peripheral blood samples of the child and his parents were collected and subjected to high-throughput sequencing. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the result was analyzed by using bioinformatic software. RESULTS: The child was found to have harbored a hemizygous c.945_948del variant in exon 2 of the ARX gene, which as a frameshifting variant has resulted in a truncated protein. His mother was found to be heterozygous for the variant, whilst his father was of wild type. The variant was unreported previously. CONCLUSION: The hemizygous c.945_948del variant of the ARX gene probably underlay the XLAG in this patient. Above finding has provided a basis for the diagnosis and genetic counseling for this family.

The Impact of Reproductive Factors on the Risk of Breast Cancer by ER/PR and HER2: A Multicenter Case-Control Study in Northern and Eastern China.

BACKGROUND: Previous studies have suggested that reproductive factors are associated with breast cancer risk. Breast cancer subtypes have distinct natural characteristics and may also have unique risk profiles. The purpose of this study was to determine whether reproductive factors affect the risk of breast cancer by estrogen receptor (ER)/progesterone receptor (PR) and HER2 status. METHODS: A multicenter, case-control study was conducted. There were 1170 breast cancer patients and 1170 age- and hospital-matched females included in the analysis. Self-reported data were collected about lifestyle behaviors, including reproductive factors. Breast cancer cases were categorized subtypes according to ER, PR, and HER2 expression as HR- positive, HER2-enriched, and triple negative breast cancer (TNBC). Multivariable logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Having ≤1 child increased risk of HR-positive breast cancer (OR 1.882; 95%CI 1.29-2.74), especially in the premenopausal group (OR 2.212; 95%CI 1.23-3.99). Compared with women who first gave birth after age 30 years, earlier age at first birth decreased the risk of HR-positive breast cancer (≤23 years: OR 0.209; 95%CI 0.14-0.30; 24-29 years: OR 0.256; 95%CI 0.18-0.36; P < .001). Compared with those who had an average breastfed/birth period of more than 2 years, those with an average period less than 6 months had an elevated risk of all subtypes (HR positive: OR 2.690; 95%CI 1.71-4.16, P < .001; HER2-enriched: OR 3.779; 95%CI, 1.62-8.79, P = .001; TNBC: OR 2.564; 95%CI 1.11-5.94, P = .022). For postmenopausal patients, shorter period of lifetime menstrual cycles (≤30 years) had an obviously decreased risk in HR-positive cases (OR 0.397; 95%CI 0.22-0.71), while there was no similar appearance in other molecular subtypes. CONCLUSION: The results suggest that reproductive behaviors affect risk of breast cancer differently according to ER/PR and HER2 status.

Microenvironment Created by SnSe2 Vapor and Pre-Selenization to Stabilize the Surface and Back Contact in Kesterite Solar Cells.

The ambient air-processed preparation of kesterite Cu2 ZnSn(S,Se)4 (CZTSSe) thin film is highly promising for the fabrication of low-cost and eco-friendly solar cells. However, the Sn volatilization loss and formation of a thick Mo(S,Se)2 interfacial layer during the traditional selenization process pose challenges for fabricating high-efficiency CZTSSe solar cells. Here, CZTS precursors prepared by a sol-gel process in ambient air are selenized and assisted with SnSe2 vapor via one- and two-step selenization to prepare a CZTSSe absorber on a Mo film and, subsequently, solar cells. For one-step selenization, the thickness of the fine grain and Mo(S,Se)2 layers near the back contact can be significantly reduced with increasing SnSe2 vapor partial pressure in the mixed selenization atmosphere, while the device efficiency is only 7.97% due to the severe interface recombination. For two-step selenization, the desired morphology and stoichiometry of the absorber can be achieved through the assistance of Sn-poor precursors selenized with high SnSe2 vapor partial pressure to regulate the Sn content in CZTSSe, yielding the highest efficiency of 10.85%. This study improves the understanding of the key role of the microenvironment during film growth towards the production of high-efficiency thin film solar cells and other photoelectronic devices.

Spatiotemporal analysis of the morbidity of global Omicron from November 2021 to February 2022.

The Omicron variant was first reported to the World Health Organization (WHO) from South Africa on November 24, 2021; this variant is spreading rapidly worldwide. No study has conducted a spatiotemporal analysis of the morbidity of Omicron infection at the country level; hence, to explore the spatial transmission of the Omicron variant among the 220 countries worldwide, we aimed to the analyze its spatial autocorrelation and to conduct a multiple linear regression to investigate the underlying factors associated with the pandemic. This study was an ecological study. Data on the number of confirmed cases were extracted from the WHO website. The spatiotemporal characteristic was described in a thematic map. The Global Moran Index (Moran's I) was used to detect the spatial autocorrelation, while the local indicators of spatial association (LISA) were used to analyze the local spatial correlation characteristics. The joinpoint regression model was used to explore the change in the trend of the Omicron incidence over time. The association between the morbidity of Omicron and influencing factors were analyzed using multiple linear regression. This study was an ecological study. Data on the number of confirmed cases were extracted from the WHO website. The spatiotemporal characteristic was described in a thematic map. The Global Moran Index (Moran's I) was used to detect the spatial autocorrelation, while the LISA were used to analyze the local spatial correlation characteristics. The joinpoint regression model was used to explore the change in the trend of the Omicron incidence over time. The association between the morbidity of Omicron and influencing factors were analyzed using multiple linear regression. The value of Moran's I was positive (Moran's I = 0.061, Z-score = 3.772, p = 0.007), indicating a spatial correlation of the morbidity of Omicron at the country level. From November 26, 2021 to February 26, 2022; the morbidity showed obvious spatial clustering. Hotspot clustering was observed mostly in Europe (locations in High-High category: 24). Coldspot clustering was observed mostly in Africa and Asia (locations in Low-Low category: 32). The result of joinpoint regression showed an increasing trend from December 21, 2021 to January 26, 2022. Results of the multiple linear regression analysis demonstrated that the morbidity of Omicron was strongly positively correlated with income support (coefficient = 1.905, 95% confidence interval [CI]: 1.354-2.456, p < 0.001) and strongly negatively correlated with close public transport (coefficient = -1.591, 95% CI: -2.461 to -0.721, p = 0.001). Omicron outbreaks exhibited spatial clustering at the country level worldwide; the countries with higher disease morbidity could impact the other countries that are surrounded by and close to it. The locations with High-High clustering category, which referred to the countries with higher disease morbidity, were mainly observed in Europe, and its adjoining country also showed high spatial clustering. The morbidity of Omicron increased from December 21, 2021 to January 26, 2022. The higher morbidity of Omicron was associated with the economic and policy interventions implemented; hence, to deal with the epidemic, the prevention and control measures should be strengthened in all aspects.

MicroRNA-7a2 Contributes to Estrogen Synthesis and Is Modulated by FSH via the JNK Signaling Pathway in Ovarian Granulosa Cells.

MicroRNA-7a2 (miR-7a2) plays fundamental roles in the female reproductive axis, and estrogen is indispensable for maintaining ovary function. However, the interaction between miR-7a2 and ovarian function is unclear. The present study aimed to determine whether and how miR-7a2 functions in estrogen synthesis. Firstly, the results verified that miR-7a was highly expressed in ovarian granulosa cells. The knockout (KO) of miR-7a2 caused infertility and abnormal ovarian function in mice. Concomitantly, the Cyp19a1 expression and estrogen synthesis were significantly inhibited, which was validated in primary granulosa cells. The mice transplanted with miR-7a2 KO ovaries showed similar results; however, estrogen supplementation reversed infertility. In the in vitro experiment, follicle-stimulating hormone (FSH) significantly improved the expression of miR-7a and Cyp19a1 and the synthesis of estrogen. However, the miR-7a2 KO markedly reversed the function of FSH. Also, FSH upregulated miR-7a by activating the (c-Jun N-terminal kinase) JNK signaling pathway. In addition, Golgi apparatus protein 1 (Glg1) was shown to be the target gene of miR-7a2. These findings indicated that miR-7a2 is essential for ovarian functions with respect to estrogen synthesis through the targeted inhibition of the expression of Glg1 and then promoting Cyp19a1 expression; the physiological process was positively regulated by FSH via the JNK signaling pathway in granulosa cells.

Long-term follow-up results of fluorescence and blue dye guided sentinel lymph node biopsy in early breast cancer.

PURPOSE: This study aimed to assess the efficacy of the combination of indocyanine green (ICG) and methylene blue (MB) dye in early breast cancer patients undergoing sentinel lymph node biopsy (SLNB). METHODS: Between January 2011 and December 2015, 1061 early breast cancer patients underwent SLNB were included. SLNB was performed for enrolled patients by injection of both ICG and MB. Detection rate, positivity, and number of sentinel lymph nodes (SLNs) by ICG and MB were analysed. Axillary recurrence and arm lymphedema at 5.6-year follow-up were reported. RESULTS: The combination of ICG and MB resulted in a very high detection rate of 99.6%, the median number of sentinel lymph nodes was 3. A total of 374 histologically confirmed positive SLNs were detected in 237 patients, 96.6% of the positive patients and 94.1% of the positive nodes could be identified by the combination of ICG and MB. After a median follow-up of 5.6 (2-9.3) years, 0.64% of patients with negative SLNs had ipsilateral axillary recurrence, and the incidence of arm lymphedema was 2.1%. CONCLUSIONS: Although the missing isotope control weakens the interpretation of the findings, the dual tracing modality of ICG and MB, without involvement of radioactive isotopes, was an effective method for SLNB in patients with early breast cancer. TRIAL REGISTRATION: ACTRN12612000109808. Registered on 23 January 2012.

Hot excitons cooling and multiexcitons Auger recombination in PbS quantum dots.

In the past few years, lead chalcogenide quantum dots (QDs) have attracted attention as a new system with a strong quantum confinement effect. In this paper, the hot-excitons cooling and Auger recombination of multiexcitons in PbS QDs are investigated by the femtosecond time-resolved transient absorption spectroscopy. The results show that the excitons dynamics in PbS QDs are closely related to the pump-photon energy and pump-pulse energy. Multiexcitons generate when the excess energy of the absorbed photons is larger than the bandgap energy in PbS QDs. The hot-excitons cooling lifetime increases but the Auger recombination lifetime decreases as the pump-photon energy and the pump-pulse energy increase. Besides, there is a competitive relation between multiple-excitons generation and hot-excitons cooling. The dynamics results of the formation and relaxation of multiexcitons in PbS QDs would shed light on the further understanding of the interaction between excitons and photons in the optoelectronic application based on PbS QDs.

Taurine Has Potential Protective Effects against the Chronic Cardiotoxicity Induced by Doxorubicin in Mice.

Doxorubicin (DOX) is an effective anticancer anthracycline drug; however, the cardiotoxicity limits its application. The aim of the present study was to investigate the potential protective effect of taurine against DOX-induced chronic cardiotoxicity in mice. We found that exogenous supplementation of taurine can inhibit the weight loss of mice caused by DOX. The increased activity of myocardial enzymes creatine kinase (CK) and lactate dehydrogenase (LDH) in response to DOX treatment were significantly hampered. In addition, taurine supplementation alleviated the decrease in superoxide dismutase (SOD) activity, glutathione (GSH) content, glutathione peroxidase 4 (Gpx4) expression, and the increase in malondialdehyde (MDA) content caused by DOX. Besides, taurine alleviated myocardial myofibrillar disruption and mitochondrial edema. Furthermore, our results showed that taurine decreased the expressions of cleaved caspase-3 and Bax/Bcl2, thereby inhibiting apoptosis. These collective data demonstrated that exogenous taurine supplementation has a potentially protective effect against the myocardial damage caused by doxorubicin in mice by enhancing antioxidant capacity and reducing oxidative damage and apoptosis.

Application of the ACOSOG Z0011 criteria to Chinese patients with breast cancer: a prospective study.

BACKGROUND: Although the ACOSOG Z0011 study showed that axillary lymph node dissection (ALND) could be avoided in a specific population of sentinel lymph node-positive patients, it is not widely accepted by Chinese surgeons. We conducted a prospective single-arm study to confirm whether or not the results of Z0011 are applicable to Chinese patients. METHODS: Patients conforming to the Z0011 criteria were prospectively enrolled at the Peking University People's Hospital Breast Center from November 2014 to June 2019. The clinicopathological features of the study group were compared with those of the Z0011 study group. Lymphedema after surgery, the incidence of local-regional recurrence, and survival were analyzed. RESULTS: One hundred forty-two patients who met the Z0011 eligibility criteria were enrolled in this study; 115 underwent sentinel lymph node biopsy (SLNB) alone. Compared with the Z0011 trial, younger patients were included (median age, 52 [26-82] years vs 54 [25-90] years; P = 0.03). For clinical T stage, tumor histology, hormone status, lymphovascular invasion, and the number of positive sentinel lymph nodes (SLNs), no statistically significant differences were observed. More patients received adjuvant chemotherapy and endocrine therapy in this study (90.85% vs 58.0% and 80.99% vs 46.6% respectively, P <0.001). A similar percentage of patients received radiotherapy, but more nodal radiotherapy procedures were carried out in our study (54.5% vs 16.9%). After a median follow-up of 29 months, only 1 patient (0.9%) had ipsilateral breast tumor recurrence, and no regional recurrence occurred. CONCLUSION: Our study showed that it is achievable to avoid ALND in patients eligible for Z0011 in China. TRIAL REGISTRATION: ClinicalTrials.gov. Registration number NCT03606616 . Retrospectively registered on 31 July 2018.

Exploring the role of green innovation and investment in energy for environmental quality: An empirical appraisal from provincial data of China.

To better analyze China's carbon neutrality target, this study investigates the effect of green innovation and investment in the energy industry on China's provincial and regional data from 1995 to 2017. Using Westerlund and Edgerton's panel cointegration test, the authors found a stable long-run relationship between CO2 emissions and its determinants. We found that under major structural breaks at the local, regional, and global levels, such as the East Asian crises of 1997, the financial crises of 2007-2008, China's RMB exchange rate reform announced on August 11, 2015, and mild recession in 2001, CO2 emissions, income, green innovation, renewable energy use, and energy industry investment are cointegrated. The environmental Kuznets curve hypothesis is valid. In the long run, income, environmental innovation, investment in the energy industry, and renewable energy consumption are key contributors in explaining CO2 emissions. The empirical evidence from augmented mean group (AMG) is consistent with the estimates of CS-ARDL. Concerning practical implications, the findings suggest that there is a need to switch the Chinese economy to more sustainable sources of energy, a viable solution to abate environmental degradation. China should introduce and shift investments to green innovation.

Use of high-resolution full-field optical coherence tomography and dynamic cell imaging for rapid intraoperative diagnosis during breast cancer surgery.

BACKGROUND: Although traditional intraoperative assessments (ie, frozen sections) may lower reoperation rates in patients with breast cancer, time/tissue limitations and accuracy concerns have discouraged their routine clinical use. Full-field optical coherence tomography (FFOCT) and dynamic cell imaging (DCI) are novel optical imaging techniques offering rapid histologic approximations that are unfettered by requisite handling steps. This study was conducted to determine the feasibility and diagnostic utility of FFOCT and DCI in examining breast and lymph node specimens during breast cancer surgery. METHODS: FFOCT and DCI were applied to normal and cancerous breast tissue, benign breast lesions, and resected axillary lymph nodes. The tissues were then subjected to conventional processing and staining (hematoxylin-eosin) for purposes of comparison. RESULTS: A total of 314 specimens, including 173 breast biopsies (malignant, 132; benign/normal, 41) and 141 resected lymph nodes (tumor-positive, 48; tumor-negative, 93), were obtained from 158 patients during breast surgery for prospective imaging evaluations. In breast cancer diagnosis, the minimum sensitivities (FFOCT, 85.6%; DCI, 88.6%) and specificities of optical imaging (FFOCT, 85.4%; DCI, 95.1%) were high, although they diverged somewhat in nodal assessments (FFOCT sensitivity, 66.7%; FFOCT specificity, 79.6%; DCI sensitivity, 83.3%; DCI specificity, 98.9%). CONCLUSIONS: These timely and tissue-sparing optical imaging techniques proved highly accurate in diagnosing breast cancer and nodal metastasis. They compare favorably with routine histologic sections and demonstrate their promise in this setting.

Simple, Amplified, and Multiplexed Detection of MicroRNAs Using Time-Gated FRET and Hybridization Chain Reaction.

The hybridization chain reaction (HCR) is a simple and sensitive method for quantifying nucleic acids. Current approaches cannot combine a washing-free sensing format with multiplexed target quantification at low concentrations, which would be highly desirable for detection both in solution and in situ. Here, we demonstrate the implementation of time-gated Förster resonance energy transfer (TG-FRET) between terbium donors and dye acceptors into HCR for multiplexed quantification of microRNAs (miR-20a and miR-21) and their DNA analogues. HCR-TG-FRET provided washing-free nucleic acid quantification with very low limits of detection down to 240 amol (1.7 pM) of microRNA and 123 amol (0.88 pM) of DNA. Efficient distinction from very homologous microRNAs demonstrated high target specificity. Multiplexing with a single measurement, a single excitation wavelength, and a single FRET pair allowed for a simultaneous quantification of miR-20a and miR-21 at concentrations between 30 and 300 pM from the same sample. HCR-TG-FRET showed similar performance for serum-free and serum-containing samples without the use of RNase inhibitors. Our results present a significant improvement in current HCR approaches regarding simplicity, sensitivity, and multiplexing. The versatile diagnostic performance of HCR-TG-FRET even in challenging biological environments presents an important advantage for advanced nucleic acid biosensing.

Upregulation of circular RNA circ-ERBB2 predicts unfavorable prognosis and facilitates the progression of gastric cancer via miR-503/CACUL1 and miR-637/MMP-19 signaling.

Gastric cancer (GC) is one of the most common malignancies of digestive system with aggressive phenotypes. Circular RNAs (circRNAs) play a pivotal function in cancer initiation and development. Nevertheless, the function and mechanism of circRNAs in gastric cancer (GC) is not fully understood. We found circ-ERBB2 was strikingly increased in GC tissues and cells. Noticeably, circ-ERBB2 upregulation in tumorous tissues was linked to patients' tumor size, depth of invasion, and overall survival. A series of gain and loss-of-function assays indicated its oncogenic role in GC cells, including cell proliferation, apoptosis, migration and invasion. We further predicted and identified circ-ERBB2 sponged miR-503 and miR-637 by bioinformatics analysis and luciferase reporter system. CACUL1 and MMP-19 were then predicted and confirmed as the target of miR-503 and miR-637, respectively. Furthermore, rescue assays indicated that circ-ERBB2 promoted tumor growth and invasion via miR-503/CACUL1 and miR-637/MMP-19 pathways, respectively. In summary, these findings demonstrated that circ-ERBB2 functions as an oncogene in GC and might be useful in developing promising therapies for this fatal malignancy.

Optically controlled ultrafast terahertz switching in a CdTe nanostructure thin film.

The speed of optical modulation on a terahertz (THz) pulse is mainly dominated by the optical response of the photocarrier. In order to achieve ultrafast THz modulation, the effective method is to reduce the lifetime of the photocarrier by introducing defects that can trap the photocarriers efficiently. In this paper, we reported the ultrafast optical modulation of THz switching in a 10 nm CdTe nanostructure film. After photoexcitation at 800/400 nm, the THz response of the film is extremely fast with a lifetime of ${\sim}{1.3}\;{\rm ps}$∼1.3ps. Further, the ultrafast transient THz transmission shows almost temperature independence down to 100 K. On the other hand, the transient absorption spectroscopy reveals that the lifetime of photocarriers in CdTe nanostructure film lasts as long as several ns. The 1.3 ps THz photoconductivity response is due to the substantial decrease of photocarrier mobility in a CdTe nanostructure, which comes from the increase of the photocarrier scattering between the photocarrier and the surface states of CdTe nanostructural film. Our experimental results provide a new method to design optically driven ultrafast THz response devices, such as THz switch and THz modulator.

Cadmium stress increases antioxidant enzyme activities and decreases endogenous hormone concentrations more in Cd-tolerant than Cd-sensitive wheat varieties.

The different wheat varieties have different tolerance to cadmium stress, while the mechanisms underlying the Cd tolerance are still poorly understood. A pot experiment was conducted to study the changes of antioxidant enzyme activities and endogenous hormones in wheat (Triticum aestivum) genotypes differing in cadmium (Cd) accumulation (low = Pingan 8 and high = Bainong 160) in different growth stages under Cd stress. The Cd treatment (3 mg/kg) increased the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) and concentrations of malondialdehyde (MDA) and abscisic acid (ABA); in contrast, it reduced the net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), intercellular carbon dioxide concentration (Ci) and the concentrations of gibberellin (GA3), auxin (IAA) and zeatin nucleoside (ZR) in wheat leaves compared to the CK (without Cd). The antioxidant enzyme activities were higher in Bainong 160 than Pingan 8 under Cd stress. In addition, the changes in endogenous hormone concentration were smaller in Bainong 160 than Pingan 8 leaves. The correlation coefficients of Bainong 160 and Pingan 8 were 0.87 and 0.66, respectively. Our results suggest that high Cd accumulation (greater Cd tolerance) in Bainong 160 is associated with higher photosynthetic parameters, higher activities of antioxidant enzyme and higher concentration of hormones than Pingan 8.

Phytochemical Analysis, Antioxidant and Analgesic Activities of Incarvillea compacta Maxim from the Tibetan Plateau.

Incarvillea compacta Maxim is a traditional Tibetan plant widely used to treat rheumatic pain and bruises. We conducted qualitative analyses by liquid chromatography-mass spectrometry and quantitative analyses of the total phenols, flavonoids, and alkaloids content of different extracts of I. compacta Maxim. Antioxidant and analgesic activity were analyzed. The results showed that the methanol extract had the highest content of the various ingredients. A total of 25 constituents were identified, of which compounds 1-23 were found for the first time in this plant. The water extract had the highest capacity to clear free radicals in the antioxidant test. The water extract had dose-dependent analgesic effects in the first and second phase in a formalin test. The latency of pain from a hot-plate test was augmented by the water extract when the dose was greater than or equal to 30 g/kg. The water extract significantly decreased the amount of writhing in a dose-dependent manner compared with the control group in the acetic acid-induced writhing test. These results showed that I. compacta Maxim is a new antioxidant and analgesic agent, and this study provides information on its ingredients for further study.