•Controls on nitrate accumulation at depth in variable charge soils were revealed.•Regolith pH, crystalline Fe, AEC and bulk density dominated nitrate accumulation.•The greater amount of Fe oxides ...gave its larger contribution than Al oxides.•Nitrate accumulation was controlled by adsorption and low hydraulic conductivity.
Nitrate accumulation at depth in variable charge soils in humid tropics and subtropics affects nitrogen (N) leaching to groundwater. However, the mechanisms on the nitrate accumulation in relation to regolith (soil and saprolite) properties are poorly understood. In this study, four upland regoliths were selected in a typical red soil Critical Zone of humid subtropical China. These regoliths with a thickness of 6–8 m, which developed from Quaternary red clay underlain by sandstone bedrock, were acidic, highly weathered, and clay loam to clay in texture. We analyzed the relationships between nitrate concentrations and the regolith physiochemical properties. The results showed that regolith pH was negatively correlated with nitrate concentrations, whereas crystalline iron (Fe) and aluminum (Al) and anion exchange capacity (AEC) were positively correlated with nitrate concentrations at depths below both soil surface and 1 m. Bulk density (BD) was significantly related to nitrate concentrations only at depths below soil surface, while depth, clay, amorphous Fe and Al, total organic carbon (C), and total N were significantly related to nitrate concentrations only at depths below 1 m. There was no significant correlation between nitrate concentrations and sand, silt, silicate bound Fe or Al, C/N, or moisture at depths below both soil surface and 1 m. Based on the random forest analysis, the relative contributions of pH, crystalline Fe, depth, AEC, BD, crystalline Al and amorphous Fe to explaining nitrate concentration variations were 28.3%, 9.5%, 4.3%, 3.4%, 2.9%, 2.8% and 2.6%, respectively. The concentration of crystalline Fe was ten times that of crystalline Al, which would account for its larger contribution to the nitrate variations. Nitrate accumulation at depth was most likely controlled both by electrostatic adsorption on crystalline Fe and Al oxides and low hydraulic conductivity of the regolith at depth, which appeared to be largely influenced by regolith pH and competitive anions. Our findings shed light on regolith internal property controls on nitrate legacy in the subtropical vadose zone and may help control nitrate contamination of groundwater in intensified agricultural regions.
Role overload is not new, but its increasing prevalence in recent years calls for further research. This study considers empowering leadership as a means of resource investment and proposes that it ...is exerted by entrepreneurs to reduce their role overload. This study adds clarity by revealing how entrepreneurs' role overload is mitigated
the intermediate mechanism of empowering leadership. Hypotheses are derived from conservation of resources theory.
Data were collected from 315 entrepreneurs in China using a three-round questionnaire survey.
This study finds that entrepreneurs' previous experience of role overload positively relates to their current empowering leadership behavior and their previous empowering leadership behavior negatively relates to their current role overload, which implies a mediating role of empowering leadership. Specifically, the second stage of the indirect effect of previous role overload on current role overload through empowering leadership is moderated by top management team (TMT) heterogeneity. When TMT heterogeneity is higher, the negative indirect effect is stronger.
This study contributes to the idea of positive psychology and extends the scope of conservation of resources theory into the fields of entrepreneurship and leadership.
To explore the regulation of microRNA-29a (miR-29a) on FOS in human nasal epithelial cells and its molecular mechanism, as well as the effects of miR-29a on the cell proliferation and apoptosis.
By ...cell transfection, gene silencing, quantitative real-time polymerase chain reaction (qRT-PCR), flow cytometry and TUNEL assay (for cell apoptosis), CCK-8 assay (for cell proliferation), dual-luciferase reporter gene assay and Western Blot, it was validated that miR-29a promoted the proliferation of human nasal epithelial cells and inhibited their apoptosis by down-regulating FOS expression in RPMI2650 and HNEpC cell lines.
①Compared with healthy controls, miR-29a expression was up-regulated and FOS mRNA expression was down-regulated in the nasal tissues from the patients with allergic rhinitis (AR). ②MiR-29a over-expression promoted the proliferation of RPMI2650 cells and HNEpC cells but inhibited their apoptosis. ③MiR-29a targeted at FOS. ④MiR-29a over-expression and FOS silencing both significantly promoted cell proliferation and inhibited cell apoptosis. After transfection with both miR-29a and FOS, there was a decrease in the proliferation but an increase in the apoptosis of cells.⑤MiR-29a promoted the proliferation of human nasal epithelial cells and inhibited their apoptosis by down-regulating FOS expression.
MiR-29a-/FOS axis can be regarded as a potential marker and a new therapy for AR.
Abstract
Traditional approaches for transition-metal catalyzed oxidative cross-coupling reactions rely on
sp
2
-hybridized starting materials, such as aryl halides, and more specifically, homogeneous ...catalysts. We report a heterogeneous Pd-catalyzed radical relay method for the conversion of a heteroarene C(
sp
3
)–H bond into ethers. Pd nanoparticles are supported on an ordered mesoporous composite which, when compared with microporous activated carbons, greatly increases the Pd
d
charge because of their strong interaction with N-doped anatase nanocrystals. Mechanistic studies provide evidence that electron-deficient Pd with Pd–O/N coordinations efficiently catalyzes the radical relay reaction to release diffusible methoxyl radicals, and highlight the difference between this surface reaction and C–H oxidation mediated by homogeneous catalysts that operate with cyclopalladated intermediates. The reactions proceed efficiently with a turn-over frequency of 84 h
−1
and high selectivity toward ethers of >99%. Negligible Pd leaching and activity loss are observed after 7 catalytic runs.
The RNA-binding metabolic enzyme LTA4H is a novel target for cancer chemoprevention and chemotherapy. Recent research shows that the increased expression of LTA4H in laryngeal squamous cell carcinoma ...(LSCC) promotes tumor proliferation, migration, and metastasis. However, its mechanism remains unclear. To investigate the potential role of LTA4H in LSCC, we employed the improved RNA immunoprecipitation and sequencing (iRIP-Seq) experiment to get the expression profile of LTA4H binding RNA in HeLa model cells, a cancer model cell that is frequently used in molecular mechanism research. We found that LTA4H extensively binds with mRNAs/pre-mRNAs and lncRNAs. In the LTA4H binding peak, the frequency of the AAGG motif reported to interact with TRA2
4 was high in both replicates. More notably, LTA4H-binding genes were significantly enriched in the mitotic cell cycle, DNA repair, RNA splicing-related pathways, and RNA metabolism pathways, which means that LTA4H has tumor-related alternative splicing regulatory functions. QRT-PCR validation confirmed that LTA4H specifically binds to mRNAs of carcinogenesis-associated genes, including LTBP3, ROR2, EGFR, HSP90B1, and lncRNAs represented by NEAT1. These results suggest that LTA4H may combine with genes associated with LSCC as an RNA-binding protein to perform a cancer regulatory function. Our study further sheds light on the molecular mechanism of LTA4H as a clinical therapy target for LSCC.
Highland barley starch (HBS), as a carbohydrate shell material with excellent performance in microcapsule applications, has rarely been reported. In the present study, three different microcapsules ...(CEO-SWSM, CEO-PM, and CEO-UM) were synthesized successfully via saturated aqueous solution method, molecular inclusion method and ultrasonic method, respectively, using HBS as shell material coupled with cinnamon essential oil (CEO) as the core material. The potential of HBS as a new shell material and the influence of synthetic methods on the performance of microcapsules, encapsulation efficiency (EE), yield, and release rate of CEO-SWSM, CEO-PM, and CEO-UM were determined, respectively. The results confirmed that CEO-PM had the most excellent EE (88.2%), yield (79.1%), as well as lowest release rate (11.5%, after 25 days of storage). Moreover, different kinetic models were applied to fit the release process of these three kinds of microcapsules: CEO-SWSM, CEO-PM, and CEO-UM had the uppermost R-squared value in the Higuchi model, the zero-order model, and the first-level model, respectively. Over all, this work put forward a novel perspective for the improved encapsulation effect of perishable core materials (e.g., essential oil) for the food industry.
To analyze the level of sex hormone in relation to keratoconus (KC).
Sixty-two eyes of 62 patients (12 females, 50 males) classified as KC and 120 eyes of 120 patients (21 females, 99 males) with ...mild to moderate myopia and astigmatism were analyzed. Plasma samples were collected and analyzed using a chemiluminescence immunoassay to determine the concentrations of estriol (E
), estradiol (E
), progesterone (P), and testosterone (T). Corneal morphological parameters, such as the central corneal thickness (CCT), thinnest corneal thickness (TCT), and maximum simulated keratometry (K
), were measured using Pentacam and Sirius.
The mean age was 23.73 ± 5.16 years for patients with KC and 23.68 ± 6.10 years for patients treated with laser vision correction (LVC). Among the patients with KC, 12 were female (19.35%) and 50 were male (80.65%). The majority of patients with KC were between 20 and 30 years old. In female patients, the concentration of T in the KC group was significantly lower than that in the LVC group (0.86 ± 0.33 vs. 1.18 ± 0.58 nmol/L;
= 0.044). There were positive correlations between T, CCT (
= 0.395,
= 0.023) and TCT (
= 0.378,
= 0.030) in female patients. In male patients, E
was higher in the KC group than the LVC group (143.75 ± 34.82 vs. 124.80 ± 43.56 pmol/L;
= 0.013), while T was significantly lower (11.59 ± 2.85 vs. 13.58 ± 4.77 nmol/L;
= 0.026). A positive correlation was found between E
and K
(
= 0.222,
= 0.007) in male patients.
Conclusively, our results showed that T level was reduced in both female and male KC plasma, while E
was increased in male KC plasma. Different levels of sex hormones are correlated with KC, which, may provide the basis of a new technique for screening and diagnosing KC with or without the assistance of current imaging techniques. Moreover, the correlations between sex hormone alterations and KC provide compelling insight into KC etiopathogenesis.
Core Ideas Conversion of upland to paddy caused significant loss of Fe within about 20 yr. The conversion impacted nearly the whole regolith far deeper than 1‐m soil profile. The magnitude of ...influence varied among elements. Despite many studies regarding the influence of the conversion from various types of land uses to paddy cultivation on soil change, little is known about how deep this influence may reach and what difference among elements may exist. To investigate the influence of the conversion from uplands to paddy fields on element behavior, we used mass‐balance equations to quantify element loss and gain throughout the regoliths from surface to bedrock at the Red Soil Critical Zone Observatory in subtropical China. The studied regoliths, with a thickness of 7 to 8 m, are acidic and highly weathered and developed from Quaternary red clay underlain by sandstone bedrock. The conversion increased the loss of Fe by 44%, whereas it decreased the loss of Mn by 14% in the top 3 m within a short timescale (about 20 yr). Slight influences of the conversion were observed for Al, K, and Mg, but no noticeable influences were found for Ca, Na, Si, and P. The observable influence of the conversion reached depths of 3 m for Fe, Mn, and Al and 1 m for Mg and K. Below the 4‐m depth, the influence was difficult to separate from the impacts of groundwater fluctuations. The lack of a noticeable influence on Ca and Na was mainly due to almost all of these elements having been depleted at the regolith–bedrock interface. Artificial flooding–drainage cycles and increases in fertilizer inputs in the paddy fields intensified the influence on element behavior via shifting the processes and sources of many elements in the regolith.
Abstract
Background
To assess and compare the efficacy, safety, accuracy, predictability and visual quality of a diffractive trifocal intraocular lens (IOL) and a refractive rotationally asymmetric ...bifocal IOL in eyes with axial myopia.
Methods
This prospective cohort study enrolled patients with implantation of the diffractive trifocal IOL or the refractive bifocal IOL. Eyes were divided into four groups according to the IOL implanted and axial length. Manifest refraction, uncorrected and corrected visual acuity at far, intermediate and near distances, prediction error of spherical equivalent (SE), contrast sensitivity and aberrations were evaluated three months after surgery.
Results
In total, 80 eyes of 80 patients were included: 20 eyes in each group. Three months postoperatively, the corrected distance visual acuity of two trifocal groups were significantly better than the axial myopia bifocal group (
P
= 0.007 and 0.043). There was no significant difference of postoperative SE (
P
= 0.478), but the SE predictability of the trifocal IOL was better, whether in axial myopia groups (
P
= 0.015) or in control groups (
P
= 0.027). The contrast sensitivity was similar among four groups. The total aberration, higher order aberration and trefoil aberration of bifocal groups were significantly higher (all
P
< 0.001).
Conclusions
The diffractive trifocal IOL and the refractive bifocal IOL both provided good efficacy, accuracy, predictability and safety for eyes with axial myopia. By contrast, the trifocal IOL had a better performance in corrected distance visual acuity and visual quality.
Trial registration
The study was retrospectively registered and posted on clinicaltrials.gov at 12/02/2020 (NCT04265846).
The Northeast China Plain (NCP) is the country’s most important grain-producing area. Unraveling how bacterial communities in this region assemble and distribute according to soil type is essential ...for sustainable agricultural development and optimizing the precise management of soil resources. In this study, 106 soil samples were collected from three typical zonal soil types (black calcium soil (BCS), black soil (BS), and dark brown soil (DBS)) spanning from west to east in the NCP. By combining soil field surveys and high-throughput microbial sequencing analysis, we found that bacterial diversity and community structure differed significantly by soil type. Proteobacteria, Gemmatimonadetes, and Acidobacteria were enriched in BCS, BS, and DBS, respectively. Compared to BSC and DBS, BS had the highest nutrient concentration and most neutral pH values, which may recruit more diverse bacterial communities and construct a more connected ecological network. Network analysis further identified Burkholderiales, Sphingomonadales, and SC_I_84 as key hubs in BS, BCS, and BCS, respectively. The majority of classified hubs consistent with the results of the linear discriminant analysis effect size belonged to the predominant biomarkers. Redundancy and Mantel test analyses revealed that the bacterial composition in various soil types showed distinctive responses to heterogeneity in soil physicochemical properties. Soil pH and TP were the primary factors shaping the soil bacterial community structure in these three soil types on the NCP. Moreover, bacterial composition and diversity were strongly related to changes in soil multifunctionality in BCS, and the relative abundances of three classes (TM1, Opitutae, and Deinococci) were the most important biotic variables for predicting BCS ecosystem multifunctionality. In summary, our results suggest that soil type variation has a strong influence in terms of shaping bacterial community structure and affecting soil multifunctionality. Correspondingly, diverse co-occurrence patterns were observed in different soil types.
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