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1.
Cereb Cortex ; 34(5)2024 May 02.
Article in English | MEDLINE | ID: mdl-38700440

ABSTRACT

While the auditory and visual systems each provide distinct information to our brain, they also work together to process and prioritize input to address ever-changing conditions. Previous studies highlighted the trade-off between auditory change detection and visual selective attention; however, the relationship between them is still unclear. Here, we recorded electroencephalography signals from 106 healthy adults in three experiments. Our findings revealed a positive correlation at the population level between the amplitudes of event-related potential indices associated with auditory change detection (mismatch negativity) and visual selective attention (posterior contralateral N2) when elicited in separate tasks. This correlation persisted even when participants performed a visual task while disregarding simultaneous auditory stimuli. Interestingly, as visual attention demand increased, participants whose posterior contralateral N2 amplitude increased the most exhibited the largest reduction in mismatch negativity, suggesting a within-subject trade-off between the two processes. Taken together, our results suggest an intimate relationship and potential shared mechanism between auditory change detection and visual selective attention. We liken this to a total capacity limit that varies between individuals, which could drive correlated individual differences in auditory change detection and visual selective attention, and also within-subject competition between the two, with task-based modulation of visual attention causing within-participant decrease in auditory change detection sensitivity.


Subject(s)
Attention , Auditory Perception , Electroencephalography , Visual Perception , Humans , Attention/physiology , Male , Female , Young Adult , Adult , Auditory Perception/physiology , Visual Perception/physiology , Acoustic Stimulation/methods , Photic Stimulation/methods , Evoked Potentials/physiology , Brain/physiology , Adolescent
2.
Cell Mol Biol (Noisy-le-grand) ; 70(3): 89-94, 2024 Mar 31.
Article in English | MEDLINE | ID: mdl-38650151

ABSTRACT

The association between the cuproptosis-related genes and the immune infiltration and their prognostic value in thyroid carcinoma is still unexplored. Bioinformatics analyses were performed with data obtained from the TCGA dataset. The aberrantly expressed genes were selected. KEGG and GO analyses were conducted to explore the enriched pathways of the up-regulated or down-regulated genes in thyroid carcinoma. Totally 1495 genes were differentially expressed (691 up-regulated, 804 down-regulated) in thyroid carcinoma (p<0.05). The 10 cuproptosis-related RNAs (DLD, LIAS, LIPT1, FDX1, DLAT, MTF1, PDHA1, CDKN2A, GLS and PDHB) were also demonstrated to be aberrantly expressed in thyroid carcinoma patients tissues. FDX1 expression was correlated with the overall survival in thyroid carcinoma patients (HR=0.4995, 95% CI: 0.2688-0.9285, p=0.0282). Further multivariate cox regression analysis revealed that DLD (HR=24.8869, 95% CI: 4.48772-138.01181, p=0.00024), and LIAS (HR=7.74092, 95% CI: 1.12194-53.40898, p=0.03783) were associated with the survival of thyroid carcinoma patients. The immune infiltration analysis demonstrated that significant correlation between the 10 cuproptosis-related genes and immune infiltration in thyroid carcinoma (p<0.01). We presented the expression profiles of dysregulated genes in thyroid carcinoma. The findings of our study highlighted the potential of cuproptosis-related genes as prognostic biomarkers for thyroid carcinoma.


Subject(s)
Gene Expression Regulation, Neoplastic , Thyroid Neoplasms , Humans , Thyroid Neoplasms/genetics , Thyroid Neoplasms/immunology , Thyroid Neoplasms/mortality , Thyroid Neoplasms/pathology , Prognosis , Female , Male , Middle Aged , Gene Expression Profiling , Biomarkers, Tumor/genetics , Kaplan-Meier Estimate , Proportional Hazards Models , Computational Biology/methods
3.
Sci Rep ; 14(1): 5824, 2024 Mar 09.
Article in English | MEDLINE | ID: mdl-38461366

ABSTRACT

We perform numerical simulations to investigate the nonlinear propagation dynamics of femtosecond Gaussian and vortex beams in fused silica. By analyzing the extent of spectral broadening, we are able to distinguish between the linear, self-focusing, and filamentation regimes. Additionally, the maximum intensity and fluence distribution within the cross-section of the vortex beams are analyzed for different incident laser energies. The results demonstrate a direct correlation between the spectral broadening and the peak intensity of the femtosecond laser pulse. As a result, this provides a theoretical foundation for distinguishing different propagation regimes, and determining critical powers for self-focusing and filamentation of both femtosecond Gaussian and structured beams.

4.
iScience ; 27(4): 109368, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38510112

ABSTRACT

Focusing attention in visual working memory (vWM) depends on the ability to filter distractors and expand the scope of targets. Although many properties of attention processes in vWM have been well documented, it remains unclear how the mechanisms of neurovascular coupling (NVC) function during attention processes in vWM. Here, we show simultaneous multimodal data that reveal the similar temporal and spatial features of attention processes during vWM. These similarities lead to common NVC outcomes across individuals. When filtering out distractors, the electroencephalography (EEG)-informed NVC displayed broader engagement across the frontoparietal network. A negative correlation may exist between behavioral metrics and EEG-informed NVC strength related to attention control. On a dynamic basis, NVC features exhibited higher discriminatory power in predicting behavior than other features alone. These results underscore how multimodal approaches can advance our understanding of the role of attention in vWM, and how NVC fluctuations are associated with actual behavior.

5.
Adv Drug Deliv Rev ; 207: 115193, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38311111

ABSTRACT

The favorable benefit-risk profile of polatuzumab vedotin, as demonstrated in a pivotal Phase Ib/II randomized study (GO29365; NCT02257567), coupled with the need for effective therapies in relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL), prompted the need to accelerate polatuzumab vedotin development. An integrated, fit-for-purpose clinical pharmacology package was designed to support regulatory approval. To address key clinical pharmacology questions without dedicated clinical pharmacology studies, we leveraged non-clinical and clinical data for polatuzumab vedotin, published clinical data for brentuximab vedotin, a similar antibody-drug conjugate, and physiologically based pharmacokinetic and population pharmacokinetic modeling approaches. We review strategies and model-informed outcomes that contributed to regulatory approval of polatuzumab vedotin plus bendamustine and rituximab in R/R DLBCL. These strategies made polatuzumab vedotin available to patients earlier than previously possible; depending on the strength of available data and the regulatory/competitive environment, they may also prove useful in accelerating the development of other agents.


Subject(s)
Immunoconjugates , Lymphoma, Large B-Cell, Diffuse , Lymphoma, Non-Hodgkin , Pharmacology, Clinical , Humans , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antibodies, Monoclonal/therapeutic use , Immunoconjugates/pharmacology , Immunoconjugates/therapeutic use , Lymphoma, Non-Hodgkin/drug therapy , Lymphoma, Non-Hodgkin/pathology , Lymphoma, Large B-Cell, Diffuse/drug therapy
6.
Opt Express ; 32(1): 387-395, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38175069

ABSTRACT

We experimentally generate a third harmonic (TH) vector optical field in deep ultraviolet wavelength range using femtosecond vector laser beams. The generated TH beams are characterized by analyzing the Stokes parameters with different input laser energies. The results show that the TH predominantly preserves the vector polarization distribution of the fundamental frequency beam. Moreover, the intensity profile of the TH exhibits a multiple-ring structure. A hybrid polarization pattern is observed in the TH, where the ellipticity is influenced by the input laser energy. Our work provides an effective and straightforward method for producing TH vector optical fields, which may facilitate potential applications such as micro/nanofabrication and super-resolution microscopy.

7.
RSC Adv ; 14(2): 1377-1385, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38174258

ABSTRACT

Chromite ore processing residue (COPR) is a hazardous waste because of leachable chromium, especially Cr(vi). Therefore, ascorbic acid (AA) and blast furnace slag (BFS) have been used to detoxify and solidify COPR. On this basis, environmental stability experiments with high temperature and freeze-thaw cycles were carried out to explore the stability performance of a solidified body with 40% COPR. The environmental stability performance was analyzed through changes in edge length, mass loss, compressive strength development, and leaching concentration of Cr(vi). The result indicated that the high-temperature environment had much more effect on the solidified body than the freeze-thaw cycle environment in these four aspects: after being maintained at 900 °C for 2 h, the compressive strength of the solidified bodies reached its minimum value (35.76 MPa). However, in the freeze-thaw cycle experiments, the compressive strength of the solidified bodies consistently remained above 80 MPa, and the leaching of hexavalent chromium was below the limit (5 mg L-1). In addition, X-ray diffraction (XRD) and Fourier transform infrared spectrometry (FTIR) analysis verified that COPR was effectively solidified through physical and chemical means. Moreover, high temperature changes the molecular structure of the solidified body, thus reducing the compressive strength and curing ability of the solidified body, while the freeze-thaw cycle experiment has little effect on it.

8.
Eur Arch Psychiatry Clin Neurosci ; 274(1): 35-44, 2024 Feb.
Article in English | MEDLINE | ID: mdl-36725736

ABSTRACT

The pathogenesis of overactivated visual perception in attention-deficit hyperactivity disorder (ADHD) remains unclear, which is interpreted as a cognitive compensation. The existing studies have proposed that perceptual abnormalities in neurodevelopmental disorders are associated with dysfunction of the contextual knowledge system, which influences the development and formation of perception. We hypothesized that alterations in contextual states may also be responsible for inducing perceptual abnormalities in ADHD. Therefore, the present study evaluated the characteristics of pre-stimulus alpha and its response to a single dose of methylphenidate (MPH). A total of 135 Chinese children participated in the first study, including 70 children with ADHD (age = 10.61 ± 1.93 years, female = 17) and 65 age- and sex-matched control children (age = 10.73 ± 1.93 years, female = 20). The second clinical trial included 19 Chinese children with ADHD (age = 11.85 ± 1.72 years, female = 4), with an identical visual spatial search task. Pre-stimulus alpha oscillations and P1 activity were significantly greater in children with ADHD than in the controls. Overactivated pre-stimulus alpha positively predicted P1. Both pre-stimulus alpha and P1 overactivation have beneficial effects on cognitive performance in children with ADHD. No intervening effect of a single dose of MPH on the compensatory activation of pre-stimulus alpha and P1 were observed. Our findings extended the perceptual activation to the contextual knowledge system, suggesting that compensatory perception in children with ADHD is more likely to be a top-down regulated cognitive operational process.


Subject(s)
Attention Deficit Disorder with Hyperactivity , Central Nervous System Stimulants , Methylphenidate , Adolescent , Child , Female , Humans , Attention Deficit Disorder with Hyperactivity/drug therapy , Attention Deficit Disorder with Hyperactivity/psychology , Central Nervous System Stimulants/pharmacology , Central Nervous System Stimulants/therapeutic use , Methylphenidate/pharmacology , Methylphenidate/therapeutic use , Visual Perception , Male , Clinical Trials as Topic
9.
Front Microbiol ; 14: 1291962, 2023.
Article in English | MEDLINE | ID: mdl-38029139

ABSTRACT

Identifying the potential factors associated with the impact of long-term drip irrigation (DI) on soil ecosystems is essential for responding to the environmental changes induced by extensive application of DI technology in arid regions. Herein, we examined the effects of the length of time that DI lasts in years (NDI) on soil bacterial diversity as well as the soil bacterial community assembly process and the factors influencing it. The results showed that long-term DI substantially reduced soil salinity and increased soil bacterial diversity while affecting the soil bacterial community structure distinctly. Null model results showed that the soil bacterial community assembly transitioned from stochastic processes to deterministic processes, as NDI increased. Homogeneous selection, a deterministic process, emerged as the dominant process when NDI exceeded 15 years. Both random forest and structural equation models showed that soil salinity was the primary factor affecting the bacterial community assembly process. In summary, this study suggested that soil bacteria respond differently to long-term DI and depends on the NDI, influencing the soil bacterial community assembly process under long-term DI.

10.
ACS Nano ; 17(23): 23488-23497, 2023 Dec 12.
Article in English | MEDLINE | ID: mdl-38010413

ABSTRACT

Permanent structural changes in pure metals that are caused by plastic activity are normally irreparable after unloading. Because of the lack of experimental evidence, it is unclear whether the plastic activity can be repaired as the size of the pure metals decreases to several nanometers; it is also unclear how the metals accommodate the plastic deformation. In this study, the in situ atomic-scale loading and unloading of ∼2 nm Ag nanocrystals was investigated, and three modes of plastic deformation were observed: (i) the phase transition from the face-centered cubic (fcc) phase to the hexagonal close-packed (hcp) phase, (ii) stacking faults, and (iii) deformation twin nucleation. We show that all three modes resulted in structural changes that were reparable, and their generation and restoration during loading and unloading were observed in situ. We discovered that the deformation modes of nanosized metals can be predicted from the ratio of the energy barriers of the fcc-hcp phase transition (ΔγH) and the deformation twin nucleation (ΔγT), which differ from those of the theoretical modes of relatively large-sized metals. The proposed ΔγH/ΔγT criterion provides insights into the deformation mechanism of nanometals.

11.
PLoS One ; 18(10): e0292560, 2023.
Article in English | MEDLINE | ID: mdl-37851628

ABSTRACT

Based on the influence of moisture content, dry density and temperature (≦ 0°C) on the thermal conductivity of lime-modified red clay, the thermal conductivity was measured by transient hot wire method. A total of 125 data were obtained and the evolution law of thermal conductivity with influencing factors was analyzed. The fitting formula of thermal conductivity of lime-modified red clay and a variety of intelligent prediction models were established and compared with previous empirical formulas. The results show that the thermal conductivity of lime-modified red clay increases linearly with water content and dry density. The change of thermal conductivity with temperature is divided into three stages. In the first stage, the thermal conductivity increases slowly with the decrease of temperature in the temperature range of-2°Cto 0°C. In the second stage, in the temperature range of-5°Cto (-2)°C, the thermal conductivity increases rapidly with the decrease of temperature. In the third stage, in the range of-10°Cto (-5)°C, the thermal conductivity changes little with the decrease of temperature, and the fitting curve tends to be stable. The fitting formula model and various intelligent prediction models can realize the accurate prediction of the thermal conductivity of lime-improved soil. Using RMSE (Root Mean Square Error) and MAPE (Mean Absolute Percentage Error) to evaluate the model, it is found that the GBDT decision tree model has the best prediction effect, the RMSE value of the predicted value is 0.084, and the MAPE value is 4.1%. The previous empirical models have poor prediction effect on the thermal conductivity of improved red clay. The intelligent prediction models such as GBDT decision tree with strong universality and high prediction accuracy are recommended to predict the thermal conductivity of soil.


Subject(s)
Soil , Temperature , Freezing , Thermal Conductivity , Clay
12.
Cell Biosci ; 13(1): 191, 2023 Oct 14.
Article in English | MEDLINE | ID: mdl-37838693

ABSTRACT

BACKGROUND: c-Jun is a proto-oncogene functioning as a transcription factor to activate gene expression under many physiological and pathological conditions, particularly in somatic cells. However, its role in early embryonic development remains unknown. RESULTS: Here, we show that c-Jun acts as a one-way valve to preserve the primed state and impair reversion to the naïve state. c-Jun is induced during the naive to primed transition, and it works to stabilize the chromatin structure and inhibit the reverse transition. Loss of c-Jun has surprisingly little effect on the naïve to primed transition, and no phenotypic effect on primed cells, however, in primed cells the loss of c-Jun leads to a failure to correctly close naïve-specific enhancers. When the primed cells are induced to reprogram to a naïve state, these enhancers are more rapidly activated when c-Jun is lost or impaired, and the conversion is more efficient. CONCLUSIONS: The results of this study indicate that c-Jun can function as a chromatin stabilizer in primed EpiSCs, to maintain the epigenetic cell type state and act as a one-way valve for cell fate conversions.

13.
Aging Dis ; 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37815900

ABSTRACT

Despite decades of research being conducted to understand what physiological deficits in the brain are an underlying basis of psychiatric diseases like schizophrenia, it has remained difficult to establish a direct causal relationship between neuronal dysfunction and specific behavioral phenotypes. Moreover, it remains unclear how metabolic processes, including amino acid metabolism, affect neuronal function and consequently modulate animal behaviors. PRODH, which catalyzes the first step of proline degradation, has been reported as a susceptibility gene for schizophrenia. It has consistently been shown that PRODH knockout mice exhibit schizophrenia-like behaviors. However, whether the loss of PRODH directly impacts neuronal function or whether such neuronal deficits are linked to schizophrenia-like behaviors has not yet been examined. Herein, we first ascertained that dysregulated proline metabolism in humans is associated with schizophrenia. We then found that PRODH was highly expressed in the oreins layer of the mouse dorsal hippocampus. By using AAV- mediated shRNA, we depleted PRODH expression in the mouse dorsal hippocampus and subsequently observed hyperactivity and impairments in the social behaviors, learning, and memory of these mice. Furthermore, the loss of PRODH led to altered neuronal morphology and function both in vivo and in vitro. Our study demonstrates that schizophrenia-like behaviors may arise from dysregulated proline metabolism due to the loss of PRODH and are associated with altered neuronal morphology and function in mice.

14.
Environ Monit Assess ; 195(11): 1347, 2023 Oct 19.
Article in English | MEDLINE | ID: mdl-37857917

ABSTRACT

With a worldwide expansion of urbanization, the conservation of urban biodiversity is attracting growing attention; it is important to study the relationship between wildlife and urban green spaces. In this study, we selected 31 parks in the urban area of Fuyang City in the North China Plain. A total of 8795 individual birds from 69 species were recorded. The study found that (a) at the local level, tree diversity and heights are the most important factors contributing to each level of bird diversity, followed by the coverage of shrubs and herbs, and (b) at the landscape level, the proportion of woodland has a strong positive correlation with the multidimensional diversity of birds, followed by the patch diversity and percent of grassland. Our results showed that artificial greenland can effectively increase bird diversity. While considering urban planning and human well-being, the proportion of vegetation and landscape in urban parks should be properly planned, providing more habitats to enrich bird diversity.


Subject(s)
Environmental Monitoring , Parks, Recreational , Animals , Humans , Cities , Ecosystem , Biodiversity , Urbanization , China , Birds
15.
Opt Express ; 31(20): 32752-32760, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37859070

ABSTRACT

The nonlinear propagation dynamics of vortex femtosecond laser pulses in optical media is a topic with significant importance in various fields, such as nonlinear optics, micromachining, light bullet generation, vortex air lasing, air waveguide and supercontinuum generation. However, how to distinguish the various regimes of nonlinear propagation of vortex femtosecond pulses remains challenging. This study presents a simple method for distinguishing the regimes of nonlinear propagation of femtosecond pulses in fused silica by evaluating the broadening of the laser spectrum as the input pulse power gradually increases. The linear, self-focusing and mature filamentation regimes for Gaussian and vortex femtosecond pulses in fused silica are distinguished. The critical powers for self-focusing and mature filamentation of both types of laser pulses are obtained. Our work provides a rapid and convenient method for distinguishing different regimes of nonlinear propagation and determining the critical powers for self-focusing and mature filamentation of Gaussian and structured laser pulses in optical media.

16.
J Hazard Mater ; 460: 132430, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37659239

ABSTRACT

Soil electrokinetic remediation is an emerging and efficient in-situ remediation technology for reducing environmental risks. Promoting the dissolution and migration of Cr in soil under the electric field is crucial to decrease soil toxicity and ecological influences. However, it is difficult to establish strong relationships between soil treatment and impact factors and to quantify their contributions. Machine learning can help establish pollutant migration models, but it is challenging to derive predictive formulas to improve remediation efficiency, describe the predictive model construction process, and reflect the importance of the predictors for better regulation. Therefore, this paper established a predictive model for the electrokinetic remediation of Cr-contaminated soil using genetic programming (GP) after determining the characteristic parameters which influenced the remediation effect, described the model's adaptive optimization process through the algorithm's function, and identified the sensitivity factors affecting the Cr removal effect. Results showed that the Cr(VI) and total Cr concentrations predicted by GP were in satisfactory agreement with the experimental values, 92% of the training data and 90% of the validation data achieved errors within 1%, and could fully reflect the target ions' content variation in different soil layers. By substituting the above prediction formulas into Sobol sensitivity analysis, it was determined that conductivity, pH, current, and moisture content dramatically affected the Cr content variation in distinguished regions. For overall contaminated area, the system current and soil pH were the most sensitive factors for Cr(VI) and total Cr contents. Remediation efforts throughout the contaminated area should focus on the role of current versus soil pH. GP and sensitivity analysis can provide decision support and operational guidance for in-situ soil electrokinetic treatment by establishing a remediation effect prediction model, expediting the development and innovation of electrokinetic technology.

17.
Life Sci Alliance ; 6(11)2023 11.
Article in English | MEDLINE | ID: mdl-37604584

ABSTRACT

Loss of c-JUN leads to early mouse embryonic death, possibly because of a failure to develop a normal cardiac system. How c-JUN regulates human cardiomyocyte cell fate remains unknown. Here, we used the in vitro differentiation of human pluripotent stem cells into cardiomyocytes to study the role of c-JUN. Surprisingly, the knockout of c-JUN improved cardiomyocyte generation, as determined by the number of TNNT2+ cells. ATAC-seq data showed that the c-JUN defect led to increased chromatin accessibility on critical regulatory elements related to cardiomyocyte development. ChIP-seq data showed that the knockout c-JUN increased RBBP5 and SETD1B expression, leading to improved H3K4me3 deposition on key genes that regulate cardiogenesis. The c-JUN KO phenotype could be copied using the histone demethylase inhibitor CPI-455, which also up-regulated H3K4me3 levels and increased cardiomyocyte generation. Single-cell RNA-seq data defined three cell branches, and knockout c-JUN activated more regulons that are related to cardiogenesis. In summary, our data demonstrated that c-JUN could regulate cardiomyocyte cell fate by modulating H3K4me3 modification and chromatin accessibility and shed light on how c-JUN regulates heart development in humans.


Subject(s)
Human Embryonic Stem Cells , Proto-Oncogene Proteins c-jun , Animals , Humans , Mice , Cell Differentiation , Chromatin/genetics , Genes, jun , Myocytes, Cardiac , Proto-Oncogene Proteins c-jun/metabolism
18.
Environ Sci Pollut Res Int ; 30(43): 98139-98155, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37608168

ABSTRACT

Cost-effective techniques with significant removal rates and low energy consumption are urgently required for in-situ Cr-contaminated soil remediation to reduce potential environmental toxicity to the ecosystem and human bodies. Electrokinetic technology is a valuable and promising soil remediation technology; however, the acidic and alkaline fronts evolution induced by the electrokinetic byproducts (H+, OH-) has significant hindering characteristics for ion removal. To effectively utilize the byproducts for enhancing Cr elimination, this paper proposed the permeable reactive composite approaching cathode with rhamnolipid-modified biochar as reactive material. Power utilization efficiency (η) was presented to comprehensively evaluate the target species elimination effect, considering removal rate and energy consumption. Results suggested that biosurfactant rhamnolipid stimulated Cr removal in acid and base fronts. Acid front induced rhamnolipid protonation reducing anolyte Cr(VI) to Cr(III), and base front induced rhamnolipid deprotonation complexing with Cr(III) and expediting Cr(VI) dissolution by electrostatic repulsion. Permeable reactive composite approaching cathode induced the maximum removal rate of Cr(VI) and Cr(III) in each section by impelling the alkaline front. Approaching cathode caused increased resistance and energy consumption in the near-anode regions, ultimately decreasing energy utilization efficiency. Optimized moving frequency and applied potential magnitude could adjust power consumption distribution in a single soil layer to obtain better electrokinetic removal performance of contaminates. This work provided essential scientific and practical importance for in-situ electrokinetic remediation of Cr(VI) and Cr(III), considering elimination efficiency and energy consumption in the future.


Subject(s)
Chromium , Ecosystem , Humans , Electrodes , Soil
19.
J Org Chem ; 88(13): 9004-9025, 2023 07 07.
Article in English | MEDLINE | ID: mdl-37306475

ABSTRACT

An efficient protocol has been established for ß-glycosylations with 2-deoxy-2-(2,4-dinitrobenzenesulfonyl)amino (2dDNsNH)-glucopyranosyl/galactopyranosyl selenoglycosides using PhSeCl/AgOTf as an activating system. The reaction features highly ß-selective glycosylation with a wide range of alcohol acceptors that are either sterically hindered or poorly nucleophilic. Thioglycoside- and selenoglycoside-based alcohols prove to be viable nucleophiles, opening up new opportunities for one-pot construction of oligosaccharides. The power of this approach is highlighted by the efficient assembly of tri-, hexa-, and nonasaccharides composed of ß-(1 → 6)-glucosaminosyl residues based on one-pot preparation of a triglucosaminosyl thioglycoside with DNs, phthaloyl, and 2,2,2-trichloroethoxycarbonyl as the protecting groups of amino groups. These glycans are potential antigens for developing glycoconjugate vaccines against microbial infections.


Subject(s)
Oligosaccharides , Thioglycosides , Glycosylation , Oligosaccharides/chemistry
20.
Front Plant Sci ; 14: 1080234, 2023.
Article in English | MEDLINE | ID: mdl-37152176

ABSTRACT

Planting spacing plays a key role in the root system architecture of the cotton group under local irrigation. This study used the Cellular Automata (CA) theory to establish a root visualization model for the cotton group at two different planting spacing (30 and 15 cm) within a leaching-pond. At a planting spacing of 30 cm, the lateral roots grew almost horizontally toward the irrigation point, and a logarithmic relationship was observed between root length density and soil water suction. However, at a planting spacing of 15 cm, the lateral roots exhibited overlapping growth and mainly competed for resources, and a power function relationship was observed between root length density and soil water suction. The main parameters of the visualization model for each treatment were essentially consistent with the experimental observations, with respective simulation errors were 6.03 and 15.04%. The findings suggest that the correlation between root length density and soil water suction in the cotton plants is a crucial driving force for the model, leading to a more accurate replication of the root structure development pathway. In conclusion, the root system exhibits a certain degree of self-similarity, which extends into the soil.

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