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1.
Front Plant Sci ; 15: 1291630, 2024.
Article in English | MEDLINE | ID: mdl-38606074

ABSTRACT

Climate change, characterized by rising atmospheric CO2 levels and temperatures, poses significant challenges to global crop production. Sweet sorghum, a prominent C4 cereal extensively grown in arid areas, emerges as a promising candidate for sustainable bioenergy production. This study investigated the responses of photosynthesis and leaf-scale water use efficiency (WUE) to varying light intensity (I) in sweet sorghum under different temperature and CO2 conditions. Comparative analyses were conducted between the A n-I, g s-I, T r-I, WUEi-I, and WUEinst-I models proposed by Ye et al. and the widely utilized the non-rectangular hyperbolic (NRH) model for fitting light response curves. The Ye's models effectively replicated the light response curves of sweet sorghum, accurately capturing the diminishing intrinsic WUE (WUEi) and instantaneous WUE (WUEinst) trends with increasing I. The fitted maximum values of A n, g s, T r, WUEi, and WUEinst and their saturation light intensities closely matched observations, unlike the NRH model. Despite the NRH model demonstrating high R 2 values for A n-I, g s-I, and T r-I modelling, it returned the maximum values significantly deviating from observed values and failed to generate saturation light intensities. It also inadequately represented WUE responses to I, overestimating WUE. Across different leaf temperatures, A n, g s, and T r of sweet sorghum displayed comparable light response patterns. Elevated temperatures increased maximum A n, g s, and T r but consistently declined maximum WUEi and WUEinst. However, WUEinst declined more sharply due to the disproportionate transpiration increase over carbon assimilation. Critically, sweet sorghum A n saturated at current atmospheric CO2 levels, with no significant gains under 550 µmol mol-1. Instead, stomatal closure enhanced WUE under elevated CO2 by coordinated g s and T r reductions rather than improved carbon assimilation. Nonetheless, this response diminished under simultaneously high temperature, suggesting intricate interplay between CO2 and temperature in modulating plant responses. These findings provide valuable insights into photosynthetic dynamics of sweet sorghum, aiding predictions of yield and optimization of cultivation practices. Moreover, our methodology serves as a valuable reference for evaluating leaf photosynthesis and WUE dynamics in diverse plant species.

3.
MedComm (2020) ; 4(4): e281, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37346933

ABSTRACT

Sanggenon C (SC), a herbal flavonoid extracted from Cortex Mori, has been mentioned to possess more than one treasured organic properties. However, the molecular mechanism of its anti-tumor impact in glioblastoma (GBM) remains unclear. In this study, we reported that SC displayed a GBM-suppressing impact in vitro and in vivo with no apparent organ toxicity. SC dramatically suppressed cell proliferation-induced cell apoptosis in GBM cells. Mechanistically, we unveiled that SC modulated the protein expression of death associated protain kinase 1 (DAPK1) by controlling the ubiquitination and degradation of DAPK1. Quantitative proteomic and Western blot analyses showed that SC improved DAPK1 protein degradation via decreasing the expression of E3 ubiquitin ligase Mindbomb 1 (MIB1). More importantly, the effects of SC on cell proliferation and apoptosis of GBM cells have been in part reversed through DAPK1 downregulation or MIB1 overexpression, respectively. These results indicated that SC might suppress cell proliferation and induce cell apoptosis by decreasing MIB1-mediated DAPK1 degradation. Furthermore, we found that SC acted synergistically with temozolomide (TMZ), an anti-cancer drug used in GBM, resulting in elevated chemotherapeutic sensitivity of GBM to TMZ. Collectively, our data suggest that SC might be a promising anti-cancer agent for GBM therapy.

4.
Genet Med ; 24(4): 915-923, 2022 04.
Article in English | MEDLINE | ID: mdl-35016843

ABSTRACT

PURPOSE: This study aimed to quantitatively assess the incidence of hearing loss in relation to age in individuals with biallelic p.V37I variant in GJB2. METHODS: Population screening of the biallelic p.V37I variant was performed in 30,122 individuals aged between 0 and 97 years in Shanghai. Hearing thresholds of the biallelic p.V37I individuals and the controls were determined by click auditory brainstem response or pure tone audiometry. RESULTS: Biallelic p.V37I was detected in 0.528% (159/30,122) of the subjects. Of the biallelic p.V37I newborns, 43.91% (18/41) passed their distortion-product otoacoustic emissions-based newborn hearing screening or had hearing thresholds lower than 20 decible above normal hearing level. The older newborns had elevated hearing thresholds, with increasing incidence of 9.52%, 23.08%, 59.38%, and 80.00% for moderate or higher grade of hearing loss in age groups of 7 to 15 years, 20 to 40 years, 40 to 60 years, and 60 to 85 years, respectively. Their hearing deteriorated at a rate of 0.40 dB hearing level per year on average; males were more susceptible, and deterioration occurred preferentially at higher sound frequencies. CONCLUSION: The biallelic p.V37I variant is associated with steadily progressive hearing loss with increasing incidence over the course of life. Most of the biallelic p.V37I individuals may develop significant hearing loss in adulthood and, can benefit from early diagnosis and intervention through wide-spread genetic screening.


Subject(s)
Deafness , Hearing Loss , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , China/epidemiology , Connexin 26 , Connexins/genetics , Deafness/genetics , Hearing Loss/diagnosis , Hearing Loss/epidemiology , Hearing Loss/genetics , Humans , Incidence , Infant , Infant, Newborn , Male , Middle Aged , Young Adult
5.
Article in Chinese | MEDLINE | ID: mdl-34304483

ABSTRACT

Objective:To evaluate the efficacy of modified mini-mental state examination(MMSE) in elderly patients with severe to profound hearing loss. Methods:A total of 24 elderly patients with severe to profound hearing loss from April to June 2019 were involved. Severe to profound hearing loss was defined by a pure-tone average of hearing thresholds at 0.5, 1, 2, and 4 kHz in the better-hearing ear. Modified and original MMSE was completed for the patients at first visit. Two weeks later, they all return hospital and MMSE were carried out by the other method. The aggregate score and subitem score of MMSE by modified and original instrument were analyzed. The degree of cognitive impairment evaluated by two methods were compared. Results:Among the 24 patients, the mean MMSE score by routine method and improved method were 10.88±9.70 and 25.29±3.70(P<0.01). The average score of sub-items of MMSE with routine method and improved method are as follows: orientation 3.21±4.03 vs 8.71±1.92(P<0.01), registration 1.04±1.33 vs 2.79±0.51(P<0.01), attention and calculation 1.63±2.02 vs 4.00±1.41(P<0.01), recall 0.79±1.14 vs 2.50±0.72(P<0.01), language 4.21±2.11 vs 7.29±1.33(P<0.01). Compared with the routine method, the degree of cognitive impairment getting better in 83.3% patients with improved method, meanwhile, 16.7% of the patients remain the same and no deterioration. Conclusion:The routine method of MMSE should be improved to seek the real cognitive state of the patients with severe to profound hearing loss.


Subject(s)
Cognitive Dysfunction , Hearing Loss , Aged , Cognitive Dysfunction/diagnosis , Hearing , Hearing Loss/diagnosis , Hearing Tests , Humans , Mental Status and Dementia Tests
6.
Front Med (Lausanne) ; 8: 662045, 2021.
Article in English | MEDLINE | ID: mdl-33842516

ABSTRACT

Background: The definition of notched audiogram for noise-induced hearing loss (NIHL) is presently based on clinical experience, but audiometric phenotypes of NIHL are highly heterogeneous. The data-driven clustering of subtypes could provide refined characteristics of NIHL, and help identify individuals with typical NIHL at diagnosis. Methods: This cross-sectional study initially recruited 12,218 occupational noise-exposed employees aged 18-60 years from two factories of a shipyard in Eastern China. Of these, 10,307 subjects with no history of otological injurie or disease, family history of hearing loss, or history of ototoxic drug use were eventually enrolled. All these subjects completed health behavior questionnaires, cumulative noise exposure (CNE) measurement, and pure-tone audiometry. We did data-driven cluster analysis (k-means clustering) in subjects with hearing loss audiograms (n = 6,599) consist of two independent datasets (n = 4,461 and n = 2,138). Multinomial logistic regression was performed to analyze the relevant characteristics of subjects with different audiometric phenotypes compared to those subjects with normal hearing audiograms (n = 3,708). Results: A total of 10,307 subjects (9,165 males [88.9%], mean age 34.5 [8.8] years, mean CNE 91.2 [22.7] dB[A]) were included, 3,708 (36.0%) of them had completely normal hearing, the other 6,599 (64.0%) with hearing loss audiograms were clustered into four audiometric phenotypes, which were replicable in two distinct datasets. We named the four clusters as the 4-6 kHz sharp-notched, 4-6 kHz flat-notched, 3-8 kHz notched, and 1-8 kHz notched audiogram. Among them, except for the 4-6 kHz flat-notched audiogram which was not significantly related to NIHL, the other three phenotypes with different relevant characteristics were strongly associated with noise exposure. In particular, the 4-6 kHz sharp-notched audiogram might be a typical subtype of NIHL. Conclusions: By data-driven cluster analysis of the large-scale noise-exposed population, we identified three audiometric phenotypes associated with distinct NIHL subtypes. Data-driven sub-stratification of audiograms might eventually contribute to the precise diagnosis and treatment of NIHL.

7.
Sensors (Basel) ; 19(13)2019 Jul 09.
Article in English | MEDLINE | ID: mdl-31324067

ABSTRACT

In the traditional raw Doppler (RD) velocity estimation method, the positioning error of the pseudorange-based global navigation satellite system (GNSS) single point positioning (SPP) solution affects the accuracy of the velocity estimation through the station-satellite unit cosine vector. To eliminate the effect of positioning errors, this paper proposes a carrier-phase-based second generation of the BeiDou navigation satellite system (BDS-2) precise point positioning (PPP) RD velocity estimation method. Compared with the SPP positioning accuracy of tens of meters, the BDS-2 kinematic PPP positioning accuracy is significantly improved to the dm level. In order to verify the reliability and applicability of the developed method, three dedicated tests, the vehicle-borne, ship-borne and air-borne platforms, were conducted. In the vehicle-borne experiment, the GNSS and inertial navigation system (INS)-integrated velocity solution was chosen as the reference. The velocity accuracy of the BDS-2 PPP RD method was better than that of SPP RD by 28.4%, 27.1% and 26.1% in the east, north and up directions, respectively. In the ship-borne and air-borne experiments, the BDS-2 PPP RD velocity accuracy was improved by 17.4%, 21.4%, 17.8%, and 38.1%, 17.6%, 17.5% in the same three directions, respectively, compared with the BDS-2 SPP RD solutions. The reference in these two tests is the real-time kinematic (RTK) Position Derivation (PD)-based velocity.

8.
Sensors (Basel) ; 19(12)2019 Jun 20.
Article in English | MEDLINE | ID: mdl-31226761

ABSTRACT

The second-generation of the Beidou Navigation Satellite System (BDS-2) has been officially providing positioning, navigation, and timing (PNT) services within the Asia-Pacific region for six years, starting from 2013. A comprehensive analysis of BDS-2 satellite broadcast navigation message performance during the past six years is highly demanded, not only for the regional service but also for the global service announced in December 2018. Therefore, this study focuses on the performance assessment of six-year BDS-2 broadcast navigation messages from 2013 to 2018 in three aspects: Message availability, anomaly detection, and signal-in-space user range errors (SIS UREs). Firstly, our results, based on International GNSS service (IGS) Multi-GNSS Experiment (MGEX) navigation files, indicate that the BDS-2 Geosynchronous Earth Orbit (GEO) and Inclined Geosynchronous Satellite Orbit (IGSO) satellites have >98.51% broadcast navigation message availability, and the Medium Earth Orbit (MEO) satellites has a ~90.03% availability. Secondly, the comparison between broadcast navigation messages and IGS precise products reveals that the User Range Accuracy Index (URAI) contained in the broadcast message could not reflect satellite performance correctly. Another satellite status indicator, space vehicle (SV) health, can only partially detect a satellite anomaly. The anomaly detection result using IGS precise products for reference shows 20241 anomalies out of 651038 broadcast navigation messages within six years. Finally, compared with the IGSO and MEO satellites, the orbit qualities of GEO satellites are significantly worse due to their large along-track orbit error. The clock performance of all satellites are at the comparable level. The satellite orbit type (GEO/IGSO/MEO) does not impact the orbit-only URE, global-average URE, and worst-case URE.

9.
Sensors (Basel) ; 18(8)2018 Aug 02.
Article in English | MEDLINE | ID: mdl-30072630

ABSTRACT

Water vapor is an important driving factor in the related weather processes in the troposphere, and its temporal-spatial distribution and change are crucial to the formation of cloud and rainfall. Global Navigation Satellite System (GNSS) water vapor tomography, which can reconstruct the water vapor distribution using GNSS observation data, plays an increasingly important role in GNSS meteorology. In this paper, a method to improve the distribution of observations in GNSS water vapor tomography is proposed to overcome the problem of the relatively concentrated distribution of observations, enable satellite signal rays to penetrate more tomographic voxels, and improve the issue of overabundance of zero elements in a tomographic matrix. Numerical results indicate that the accuracy of the water vapor tomography is improved by the proposed method when the slant water vapor calculated by GAMIT is used as a reference. Comparative results of precipitable water vapor (PWV) and water vapor density (WVD) profiles from radiosonde station data indicate that the proposed method is superior to the conventional method in terms of the mean absolute error (MAE), standard deviations (STD), and root-mean-square error (RMS). Further discussion shows that the ill-condition of tomographic equation and the richness of data in the tomographic model need to be discussed separately.

10.
Sensors (Basel) ; 17(6)2017 Jun 12.
Article in English | MEDLINE | ID: mdl-28604640

ABSTRACT

Satellite orbit and clock corrections are always treated as known quantities in GPS positioning models. Therefore, any error in the satellite orbit and clock products will probably cause significant consequences for GPS positioning, especially for real-time applications. Currently three types of satellite products have been made available for real-time positioning, including the broadcast ephemeris, the International GNSS Service (IGS) predicted ultra-rapid product, and the real-time product. In this study, these three predicted/real-time satellite orbit and clock products are first evaluated with respect to the post-mission IGS final product, which demonstrates cm to m level orbit accuracies and sub-ns to ns level clock accuracies. Impacts of real-time satellite orbit and clock products on GPS point and relative positioning are then investigated using the P3 and GAMIT software packages, respectively. Numerical results show that the real-time satellite clock corrections affect the point positioning more significantly than the orbit corrections. On the contrary, only the real-time orbit corrections impact the relative positioning. Compared with the positioning solution using the IGS final product with the nominal orbit accuracy of ~2.5 cm, the real-time broadcast ephemeris with ~2 m orbit accuracy provided <2 cm relative positioning error for baselines no longer than 216 km. As for the baselines ranging from 574 to 2982 km, the cm-dm level positioning error was identified for the relative positioning solution using the broadcast ephemeris. The real-time product could result in <5 mm relative positioning accuracy for baselines within 2982 km, slightly better than the predicted ultra-rapid product.

11.
Sci Rep ; 5: 10273, 2015 Jul 21.
Article in English | MEDLINE | ID: mdl-26196963

ABSTRACT

Tropospheric correction models are receiving increasing attentions, as they play a crucial role in Global Navigation Satellite System (GNSS). Most commonly used models to date include the GPT2 series and the TropGrid2. In this study, we analyzed the advantages and disadvantages of existing models and developed a new model called the Improved Tropospheric Grid (ITG). ITG considers annual, semi-annual and diurnal variations, and includes multiple tropospheric parameters. The amplitude and initial phase of diurnal variation are estimated as a periodic function. ITG provides temperature, pressure, the weighted mean temperature (Tm) and Zenith Wet Delay (ZWD). We conducted a performance comparison among the proposed ITG model and previous ones, in terms of meteorological measurements from 698 observation stations, Zenith Total Delay (ZTD) products from 280 International GNSS Service (IGS) station and Tm from Global Geodetic Observing System (GGOS) products. Results indicate that ITG offers the best performance on the whole.

12.
Talanta ; 76(4): 956-9, 2008 Aug 15.
Article in English | MEDLINE | ID: mdl-18656684

ABSTRACT

In this article, a new method for the determination of triazine herbicides atrazine and simazine in environment aqueous samples was developed. It was based on solid-phase extraction (SPE) using bamboo charcoal as adsorbent and high-performance liquid chromatography-ultraviolet detector (HPLC-UV) for the enrichment and determination of atrazine and simazine at trace level. Related important factors influencing the extraction efficiency, such as the kind of eluent and its volume, flow rate of the sample, pH of the sample, and volume of the sample, were investigated and optimized in detail. Under the optimal conditions, the experimental results showed that excellent linearity was obtained over the range of 0.5-30 microg L(-1) with correlation coefficients 0.9991 and 0.9982, for atrazine and simazine, respectively; and the relative standard deviations of two analytes were 8.3, 8.7%, respectively. The proposed method was successfully applied to the analysis of tap water and well water samples. And satisfactory spiked recoveries were obtained in the range of 75.2-107.1%. The above results indicated that the developed method was an excellent alternative for the routine analysis in environmental field.


Subject(s)
Atrazine/analysis , Chromatography, High Pressure Liquid/methods , Simazine/analysis , Solid Phase Extraction/methods , Spectrophotometry, Ultraviolet/methods , Water/analysis , Adsorption , Charcoal , Herbicides/analysis , Hydrogen-Ion Concentration , Sasa , Ultraviolet Rays , Water/chemistry , Water Pollutants, Chemical/analysis
13.
Anal Bioanal Chem ; 385(6): 1082-6, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16770579

ABSTRACT

This paper demonstrates headspace liquid-phase microextraction (HS-LPME) as used for the determination of volatile residual solvents in pharmaceutical products. This method is based on headspace liquid-phase microextraction capillary column gas chromatography. Under optimum conditions, the linerary of the method ranged from 1 to 1,000 mg l(-1). The limits of detection are 0.2-6.0 [corrected] mg l(-1) and relative standard deviations (RSD) for most of the volatile solvents were below 10%. This novel method is applied to the analysis of volatile residual solvents in pharmaceutical products with satisfactory results.


Subject(s)
Chromatography, Gas/methods , Drug Contamination , Flame Ionization/methods , Pharmaceutical Preparations/analysis , Solvents/analysis , Chromatography, Gas/standards , Flame Ionization/standards , Microchemistry/methods , Reproducibility of Results , Volatilization
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