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1.
Small ; 20(35): e2401622, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38682610

RESUMO

Single-network hydrogels are often too fragile to withstand mechanical loading, whereas double-network hydrogels typically exhibit significant hysteresis during cyclic stretching-releasing process due to the presence of a sacrificial network. Consequently, it is a considerable challenge for designing hydrogels that are both low in hysteresis and high in toughness for applications requiring dynamic mechanical loads. Herein, the study introduced a novel "sliding tangle island" strategy for creating tough and low-hysteresis hydrogels, which are prepared through in situ polymerization of highly concentrated acrylamides (AM) to form numerous entanglements within the MXene spacing without any chemical crosslinker. The MXene entangled with long polyacrylamide (PAM) chains to form tangle island that served as a relay station to transmit stress to neighboring molecular chains. This mechanism helps alleviate stress concentration and enhances energy dissipation efficiency, thereby reducing mechanical hysteresis. The resulting hydrogel exhibited exceptional properties, including high stretchability (≈900%), low hysteresis (less than 7%), high toughness (1.34 MJ m-3), and excellent sensing performance to rival the commercial hydrogel electrode. Therefore, this work sheds light on feasible design of energy dissipation structure to reduce the hysteresis of the composite hydrogels.

2.
Appl Environ Microbiol ; 90(3): e0007024, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38385702

RESUMO

Nitrogen availability limits the net primary productivity in alpine meadows on the Qinghai-Tibetan Plateau, which is regulated by ammonia-oxidizing microorganisms. However, little is known about the elevational patterns of soil ammonia oxidizers in alpine meadows. Here, we investigated the potential nitrification rate (PNR), abundance, and community diversity of soil ammonia-oxidizing microorganisms along the altitudinal gradient between 3,200 and 4,200 m in Qinghai-Tibetan alpine meadows. We found that both PNR and amoA gene abundance declined from 3,400 to 4,200 m but lowered at 3,200 m, possibly due to intense substrate competition and biological nitrification inhibition from grasses. The primary contributors to soil nitrification were ammonia-oxidizing archaea (AOA), and their proportionate share of soil nitrification increased with altitude in comparison to ammonia-oxidizing bacteria (AOB). The alpha diversity of AOA increased by higher temperature and plant richness at low elevations, while decreased by higher moisture and low legume biomass at middle elevations. In contrast, the alpha diversity of AOB increased along elevation. The elevational patterns of AOA and AOB communities were primarily driven by temperature, soil moisture, and vegetation. These findings suggest that elevation-induced climate changes, such as shifts in temperature and water conditions, could potentially alter the soil nitrification process in alpine meadows through changes in vegetation and soil properties, which provide new insights into how soil ammonia oxidizers respond to climate change in alpine meadows.IMPORTANCEThe importance of this study is revealing that elevational patterns and nitrification contributions of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) communities were primarily driven by temperature, soil moisture, and vegetation. Compared to AOB, the relative contribution of AOA to soil nitrification increased at higher elevations. The research highlights the potential impact of elevation-induced climate change on nitrification processes in alpine meadows, mediated by alterations in vegetation and soil properties. By providing new insights into how ammonia oxidizers respond to climate change, this study contributes valuable knowledge to the field of microbial ecology and helps predict ecological responses to environmental changes in alpine meadows.


Assuntos
Bactérias , Solo , Bactérias/genética , Solo/química , Amônia , Nitrificação , Oxirredução , Microbiologia do Solo , Archaea/genética , Filogenia
3.
New Phytol ; 243(4): 1312-1328, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38934095

RESUMO

Recent droughts have strongly impacted forest ecosystems and are projected to increase in frequency, intensity, and duration in the future together with continued warming. While evidence suggests that tree diversity can regulate drought impacts in natural forests, few studies examine whether mixed tree plantations are more resistant to the impacts of severe droughts. Using natural variations in leaf carbon (C) and nitrogen (N) isotopic ratios, that is δ13C and δ15N, as proxies for drought response, we analyzed the effects of tree species richness on the functional responses of tree plantations to the pan-European 2018 summer drought in seven European tree diversity experiments. We found that leaf δ13C decreased with increasing tree species richness, indicating less drought stress. This effect was not related to drought intensity, nor desiccation tolerance of the tree species. Leaf δ15N increased with drought intensity, indicating a shift toward more open N cycling as water availability diminishes. Additionally, drought intensity was observed to alter the influence of tree species richness on leaf δ15N from weakly negative under low drought intensity to weakly positive under high drought intensity. Overall, our findings suggest that dual leaf isotope analysis helps understand the interaction between drought, nutrients, and species richness.


Assuntos
Biodiversidade , Isótopos de Carbono , Secas , Isótopos de Nitrogênio , Folhas de Planta , Estações do Ano , Árvores , Folhas de Planta/fisiologia , Árvores/fisiologia , Isótopos de Carbono/análise , Europa (Continente) , Especificidade da Espécie
4.
Chemistry ; : e202402269, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058363

RESUMO

This study aims to enhance the performance of supercapacitors, focusing particularly on optimizing electrode materials. While pure NiMn layered double hydroxides (LDHs) exhibit excellent electrochemical properties, they have limitations in achieving high specific capacitance. Therefore, this paper successfully synthesized composite materials of NiMn LDHs with varying loadings of graphene oxide (GO) using a hydrothermal method. Systematic physicochemical characterization of the synthesized materials, such as powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), and Raman spectroscopy, revealed the influence of GO doping on the microstructure and electrochemical performance of NiMn LDHs. Electrochemical tests demonstrated that the NiMn LDHs/GO electrode material exhibited optimal electrochemical performance with a specific capacitance of 2096 F g-1 at 1 A g-1 current density and 1471 F g-1 at 10 A g-1, when GO doping level was 0.45 wt%. Furthermore, after 1000 cycles of stability testing, the material retained 53.3% capacitance at 5 A g-1, indicating good cyclic stability. This study not only provides new directions for research on supercapacitor electrode materials but also offers new strategies for developing low-cost and efficient electrode materials.

5.
Neurochem Res ; 49(1): 29-37, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37725293

RESUMO

As one of the most common neuropathic disorders, neuropathic pain often has a negative impact on patients with persistent pain, mood disorders and sleep disturbances. Currently, neuropathic pain is not treated with any specific drug, instead, drugs for other diseases are used as replacements in clinics, but most have adverse effects. In recent years, the role of spinal cord microglia in the pathogenesis of neuropathic pain has been widely recognized, and they are being explored as potential therapeutic targets. Spinal microglia are known to be involved in the pathogenic mechanisms of neuropathic pain through purine signaling, fractalkine signaling, and p38 MAPK signaling. Exercise is a safe and effective treatment, and numerous studies have demonstrated its effectiveness in improving neurological symptoms. Nevertheless, it remains unclear what the exact molecular mechanism is. This review summarized the specific molecular mechanisms of exercise in alleviating neuropathic pain by mediating the activity of spinal microglia and maintaining the phenotypic homeostasis of spinal microglia through purine signaling, fractalkine signaling and p38 MAPK signaling. In addition, it has been proposed that different intensities and types of exercise affect the regulation of the above-mentioned signaling pathways differently, providing a theoretical basis for the improvement of neuropathic pain through exercise.


Assuntos
Microglia , Neuralgia , Ratos , Animais , Humanos , Microglia/metabolismo , Quimiocina CX3CL1/metabolismo , Ratos Sprague-Dawley , Neuralgia/metabolismo , Medula Espinal/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Purinas/metabolismo
6.
Phys Chem Chem Phys ; 26(15): 11570-11581, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38533820

RESUMO

The capture and separation of CF4 from CF4/N2 mixture gas is a crucial issue in the electronics industry, as CF4 is a commonly used etching gas and the ratio of CF4 to N2 directly affects process efficiency. Utilizing high-throughput computational screening techniques and grand canonical Monte Carlo (GCMC) simulations, we comprehensively screened and assessed 247 types of pure silicon zeolite materials to determine their adsorption and separation performance for CF4/N2 mixtures. Based on screening, the relationships between the structural parameters and adsorption and separation properties were meticulously investigated. Four indicators including adsorption selectivity, working capacity, adsorbent performance score (APS), and regenerability (R%) were used to evaluate the performance of adsorbents. Based on the evaluation, we selected the top three best-performing zeolite structures for vacuum swing adsorption (LEV, AWW and ESV) and pressure swing adsorption (AVL, ZON, and ERI) processes respectively. Also, we studied the preferable adsorption sites of CF4 and N2 in the selected zeolite structures through centroid density distributions at the molecule level. We expect the study may provide some valuable guidance for subsequent experimental investigations on adsorption and separation of CF4/N2.

7.
Appl Microbiol Biotechnol ; 108(1): 261, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38472661

RESUMO

Non-coding RNA (ncRNA) plays a vital part in the regulation of immune responses, growth, and development in plants and animals. Here, the identification, characteristic analysis, and molecular verification of circRNAs in Apis cerana cerana worker larval guts were conducted, followed by in-depth investigation of the expression pattern of larval circRNAs during Ascosphaera apis infection and exploration of the potential regulatory part of differentially expressed circRNAs (DEcircRNAs) in host immune responses. A total of 3178 circRNAs in the larval guts of A. c. cerana were identified, with a length distribution ranging from 15 to 96,007 nt. Additionally, 155, 95, and 86 DEcircRNAs were identified in the in the 4-, 5-, and 6-day-old larval guts following A. apis infection. These DEcircRNAs were predicted to target 29, 25, and 18 parental genes relevant to 12, 20, and 17 GO terms as well as 144, 114, and 61 KEGG pathways, including 5 cellular and 4 humoral immune pathways. Complex competing endogenous RNA (ceRNA) regulatory networks were detected as being formed among DEcircRNAs, DEmiRNAs, and DEmRNAs. The target DEmRNAs were engaged in 36, 47, and 47 GO terms as well as 331, 332, and 331 pathways, including 6 cellular and 6 humoral immune pathways. Further, 19 DEcircRNAs, 5 DEmiRNAs, and 3 mRNAs were included in the sub-networks relative to 3 antioxidant enzymes. Finally, back-splicing sites within 15 circRNAs and the difference in the 15 DEcircRNAs' expression between uninoculated and A. apis-inoculated larval guts were confirmed based on molecular methods. These findings not only enrich our understanding of bee host-fungal pathogen interactions but also lay a foundation for illuminating the mechanism underlying the DEcircRNA-mediated immune defense of A. c. cerana larvae against A. apis invasion. KEY POINTS: • The expression pattern of circRNAs was altered in the A. cerana worker larval guts following A. apis infection. • Back-splicing sites within 15 A. cerana circRNAs were verified using molecular approaches. DEcircRNAs potentially modulated immune responses and antioxidant enzymes in A. apis-challenged host guts.


Assuntos
MicroRNAs , Micoses , Abelhas/genética , Animais , Larva/microbiologia , RNA Circular/genética , Antioxidantes , RNA/genética , MicroRNAs/genética
8.
J Chem Phys ; 161(8)2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39206826

RESUMO

We present an efficient real space formalism for hybrid exchange-correlation functionals in generalized Kohn-Sham density functional theory (DFT). In particular, we develop an efficient representation for any function of the real space finite-difference Laplacian matrix by leveraging its Kronecker product structure, thereby enabling the time to solution of associated linear systems to be highly competitive with the fast Fourier transform scheme while not imposing any restrictions on the boundary conditions. We implement this formalism for both the unscreened and range-separated variants of hybrid functionals. We verify its accuracy and efficiency through comparisons with established planewave codes for isolated as well as bulk systems. In particular, we demonstrate up to an order-of-magnitude speedup in time to solution for the real space method. We also apply the framework to study the structure of liquid water using ab initio molecular dynamics, where we find good agreement with the literature. Overall, the current formalism provides an avenue for efficient real-space DFT calculations with hybrid density functionals.

9.
Ophthalmic Res ; 67(1): 488-498, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39111293

RESUMO

INTRODUCTION: The aim of the study was to investigate the association of parameters related to accommodation and convergence and axial elongation in basic intermittent exotropia (IXT) patients and the potential clinical predictors of axial length (AL) growth. METHODS: A total of 140 basic IXT patients were recruited in this study. The medians of AL growth in different age brackets were chosen to divide the subjects into group A (slower axial elongation group, n = 69) and group B (faster axial elongation group, n = 71). Parameters of dominant and nondominant eyes were compared and analyzed during the 12-month follow-up period. The parameters, including baseline refraction, angle of deviation, Newcastle control score (NCS), accommodative amplitude (AMP), accommodative facility (AMF), accommodative response, positive or negative relative accommodation (PRA/NRA), and near point of convergence (NPC), were analyzed via univariate and multivariate regression. RESULTS: Subjects in the faster axial elongation group tended to have more myopic spherical equivalents (t = 3.956, p < 0.001), greater AMPs of dominant eyes (t = -2.238, p = 0.027), and fewer near points of convergence (t = 2.347, p = 0.020) than in the slower axial elongation group. For dominant eyes, logistic and linear regression analysis revealed that more negative spherical equivalents (OR = 0.603, p < 0.001; ß = -0.045, p < 0.001), greater AMPs (OR = 1.201, p = 0.027; ß = 0.023, p = 0.010), and less near points of convergence (OR = 0.883, p = 0.021; ß = -0.012, p = 0.019) were correlated with the faster axial elongation. For nondominant eyes, a more myopic spherical equivalent (OR = 0.682; p = 0.001; ß = -0.029, p = 0.005) was the only parameter correlated with faster axial elongation through regression analysis. CONCLUSION: In children with basic IXT, faster axial elongation in the dominant eyes was associated with more myopic spherical equivalents, greater AMPs, and lower NPCs. These accommodative parameters can serve as potential clinical indicators for monitoring myopia progression in addition to AL.


Assuntos
Acomodação Ocular , Comprimento Axial do Olho , Convergência Ocular , Exotropia , Refração Ocular , Humanos , Acomodação Ocular/fisiologia , Exotropia/fisiopatologia , Masculino , Feminino , Comprimento Axial do Olho/fisiopatologia , Criança , Convergência Ocular/fisiologia , Pré-Escolar , Refração Ocular/fisiologia , Seguimentos , Acuidade Visual/fisiologia , Visão Binocular/fisiologia , Estudos Retrospectivos
10.
J Obstet Gynaecol Res ; 50(6): 1051-1055, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38423535

RESUMO

Primary leiomyosarcoma of the fallopian tube (PLFT) is an extremely rare gynecological malignancy that has only been described in case reports. Fertility-sparing treatment for PLFT has not been reported previously. A 24-year-old nulligravida woman was diagnosed with stage IC1 PLFT in the right fallopian tube after experiencing right lower quadrant pain for 2 weeks. She underwent laparoscopic right salpingectomy to preserve fertility followed by adjuvant chemotherapy with gemcitabine/docetaxel. She subsequently became pregnant spontaneously, delivering a term baby 27 months after treatment. This appears to be the only report of the use of fertility-preserving treatment for PLFT. The success of the treatment provides valuable information on the preservation of fertility in young women with PLFT.


Assuntos
Neoplasias das Tubas Uterinas , Preservação da Fertilidade , Leiomiossarcoma , Humanos , Feminino , Leiomiossarcoma/cirurgia , Leiomiossarcoma/tratamento farmacológico , Gravidez , Preservação da Fertilidade/métodos , Neoplasias das Tubas Uterinas/tratamento farmacológico , Neoplasias das Tubas Uterinas/cirurgia , Adulto Jovem , Salpingectomia , Adulto , Docetaxel/uso terapêutico , Docetaxel/administração & dosagem
11.
Plant Dis ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38506905

RESUMO

The occurrence of rust fungi on Corydalis bungeana Turcz. and Salix babylonica L. were found in same area of Hebei Province, China from 2022 to 2023. The life cycle connection of these rust fungi was suspected because Peng et al. (2022) reported the life cycle of Melampsora ferrinii Toome & Aime by inoculations, producing spermogonia and aecia on Corydalis species, and uredinia on S. babylonica. The morphology of the uredinial and telial stages on S. babylonica collected in the field was identical with the description of M. ferrinii by Toome and Aime (2015), and its identity was confirmed by phylogenetic analyses using the method of Ji et al. (2020) (LSU-PP087777, ITS-PP091274; Similarity with M. ferrinii: LSU-100%, ITS-99.85%). To confirm the life cycle of this rust fungus, inoculations were conducted on C. bungeana with basidiospores obtained from the teliospores on fallen leaves of Salix babylonica. The fallen leaves producing basidiospores were cut into small pieces (ca. 5 mm2) and placed on healthy leaves of C. bungeana. The inoculated plants were kept in a moist plastic box in darkness at 15-20℃ for 2 days and then transferred to the floor near windows at about 15-20℃ for observations. Ten days after inoculations small yellow spots of spermogonia appeared on the upper surface of the leaves of C. bungeana. About 7 days later, pale yellow aecia with aeciospores were produced mainly on the under surface of the leaves and petioles. The morphology of rust fungus on C. bungeana collected from the fields and obtained by inoculations was identical with the description by Peng et al. (2022). Phylogenetic analyses also showed that a specimen on C. bungeana collected from the field (LSU-OR607838, ITS-OR612063) were included into the same clade of M. ferrinii (Similarity: LSU-100 %, ITS-99.85). Based on morphology, inoculations and DNA sequence analyses, the rust fungi on C. bungeana and S. babylonica are identified as different stages of life cycle of M. ferrinii. This rust fungus has been reported to produce spermogonia and aecia on C. acuminata Franch., C. edulis Maxim. and C. racemosa (Thunb.) Pers. in China (Peng et al. 2022), and uredinia and telia on S. babylonica in USA, Argentina and Iran (Toome and Aime 2015, Abbasi et al. 2024), and on Salix sp. in Chile (Zapata 2016). Therefore, C. bungeana is a new host for M. ferrinii, and its field occurrence on S. babylonica is reported for the first time in China although Peng et al. (2022) reported successful results in its inoculations to S. babylonica in China. This report contributes to the control of rust diseases caused by this species. Specimens used in this experiment were deposited in the Fungal Herbarium of the Jilin Agricultural University, Changchun, China (HMJAU) and sequences newly analyzed were deposited in GenBank.

12.
Chem Soc Rev ; 52(4): 1428-1455, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36728265

RESUMO

Cucurbit[n]uril supramolecular chemistry has developed rapidly since 2001 when different cucurbit[n]uril homologues (Q[n]) were successfully separated in pure form. The combination of Q[n] cavity size and various types of external stimuli has given birth to numerous types of Q[n]-based mechanically interlocked molecules (MIMs), including (pseudo)rotaxanes, catenanes, dendrimers and poly(pseudo)rotaxanes. In this review article, the important advances in the field of Q[n]-based MIMs over the past two decades are highlighted. This review also describes examples of heterowheel (pseudo)rotaxanes and poly(pseudo)rotaxanes involving Q[n]s, and reflects on the opportunities and challenges of constructing Q[n]-based stimuli-responsive MIMs.

13.
Int J Mol Sci ; 25(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38612553

RESUMO

Mesenchymal stem/stromal cells (MSCs) are an extensively studied cell type in clinical trials due to their easy availability, substantial ex vivo proliferative capacity, and therapeutic efficacy in numerous pre-clinical animal models of disease. The prevailing understanding suggests that their therapeutic impact is mediated by the secretion of exosomes. Notably, MSC exosomes present several advantages over MSCs as therapeutic agents, due to their non-living nature and smaller size. However, despite their promising therapeutic potential, the clinical translation of MSC exosomes is hindered by an incomplete understanding of their biodistribution after administration. A primary obstacle to this lies in the lack of robust labels that are highly sensitive, capable of directly and easily tagging exosomes with minimal non-specific labeling artifacts, and sensitive traceability with minimal background noise. One potential candidate to address this issue is radioactive iodine. Protocols for iodinating exosomes and tracking radioactive iodine in live imaging are well-established, and their application in determining the biodistribution of exosomes has been reported. Nevertheless, the effects of iodination on the structural or functional activities of exosomes have never been thoroughly examined. In this study, we investigate these effects and report that these iodination methods abrogate CD73 enzymatic activity on MSC exosomes. Consequently, the biodistribution of iodinated exosomes may reflect the biodistribution of denatured exosomes rather than functionally intact ones.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Neoplasias da Glândula Tireoide , Animais , Radioisótopos do Iodo , Distribuição Tecidual
14.
Mycoscience ; 65(2): 79-85, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39234514

RESUMO

Caeoma mori (≡ Aecidium mori), known as the mulberry rust which is an anamorphic rust fungus forming only aecidioid uredinia, were found on Morus alba in Ibaraki and Saitama Prefectures, Japan. Molecular phylogenetic analyses using the combined dataset of sequences from 28S and 18S of the nuclear ribosomal RNA gene and Cytochrome-c-oxidase subunit 3 of the mitochondrial DNA revealed that this anamorphic rust fungus was a member of the clade composed of the genus Gymnosporangium. Therefore, a new combination, Gymnosporangium mori is proposed for this species. Additionally, a new combination, G. brucense for Roestelia brucensis is proposed by phylogenetic evidence.

15.
J Infect Dis ; 228(6): 715-722, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37202147

RESUMO

BACKGROUND: An orally aerosolized adenovirus type-5 vector-based coronavirus disease 2019 (COVID-19) vaccine (Ad5-nCoV) has recently been authorized for boosting immunization in China. Our study aims to assess the environmental impact of the use of aerosolized Ad5-nCoV. METHODS: We collected air samples from rooms, swabs from the desks on which the vaccine nebulizer was set, mask samples from participants, and blood samples of nurses who administered the inoculation in the clinical trials. The viral load of adenovirus type-5 vector in the samples and the antibody levels against the wild-type severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain in serum were detected. RESULTS: Only one (4.00%) air sample collected before initiation of vaccination was positive and most air samples collected during and after vaccination were positive (97.96%, 100%, respectively). All nurses in trial A showed at least 4-fold increase of the neutralizing antibody against SARS-CoV-2 after initiation of the study. In trial B, the proportion of positive mask samples was 72.97% at 30 minutes after vaccination, 8.11% at day 1, and 0% at days 3, 5, and 7. CONCLUSIONS: Vaccination with the orally aerosolized Ad5-nCoV could result in some spillage of the vaccine vector viral particles in the environment and cause human exposure. Clinical Trials Registration. NCT04840992 and NCT05303584.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/prevenção & controle , SARS-CoV-2/genética , Ensaios Clínicos Controlados Aleatórios como Assunto , Anticorpos Neutralizantes , Adenoviridae/genética , Anticorpos Antivirais
16.
Angew Chem Int Ed Engl ; 63(8): e202318224, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38095880

RESUMO

The built-in electric field of the polymer semiconductors could be regulated by the dipole moment of its building blocks, thereby promoting the separation of photogenerated carriers and achieving efficient solar-driven water splitting. Herein, three perylene diimide (PDI) polymers, namely oPDI, mPDI and pPDI, are synthesized with different phenylenediamine linkers. Notably, the energy level structure, light-harvesting efficiency, and photogenerated carrier separation and migration of polymers are regulated by the orientation of PDI unit. Among them, oPDI enables a large dipole moment and robust built-in electric field, resulting in enhanced solar-driven water splitting performance. Under simulated sunlight irradiation, oPDI exhibits the highest photocurrent of 115.1 µA cm-2 for photoelectrochemical oxygen evolution, which is 11.5 times that of mPDI, 26.8 times that of pPDI and 104.6 times that of its counterparts PDI monomer at the same conditions. This work provides a strategy for designing polymers by regulating the orientation of structural units to construct efficient solar energy conversion systems.

17.
New Phytol ; 238(2): 567-583, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36651017

RESUMO

Mistletoes play important roles in biogeochemical cycles. Although many studies have compared nutrient concentrations between mistletoes and their hosts, no general patterns have been found and the nutrient uptake mechanisms in mistletoes have not been fully resolved. To address the water and nutrient relations in mistletoes compared with their hosts, we measured 11 nutrient elements, two isotope ratios and two leaf morphological traits for 11 mistletoe and 104 host species from four sites across a large environmental gradient in southwest China. Mistletoes had significantly higher phosphorus, potassium, and boron concentrations, nitrogen isotope ratio, and lower carbon isotope ratio (δ13 C) indicative of lower water-use efficiency than hosts, but other elements were similar to those in hosts. Sites explained most of the variation in the multidimensional trait space. With increasing host nitrogen concentration, both mistletoe δ13 C and the difference between mistletoe and host δ13 C increased, providing evidence to support the 'nitrogen parasitism hypothesis'. Host nutrient concentrations were the best predictors for that of the mistletoe nutrient elements in most cases. Our results highlight the important roles of environmental conditions and host nutrient status in determining mistletoe nutrient pools, which together explain their trophic interactions with hosts in subtropical and tropical ecosystems.


Assuntos
Erva-de-Passarinho , Ecossistema , Água , Nitrogênio , Nutrientes
18.
Clin Genet ; 103(1): 87-92, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36046950

RESUMO

Hereditary spastic paraplegia (HSP) is a heterogeneous group of inherited neurodegenerative disease characterized by progressive lower limb spasticity. Recent studies revealed that biallelic variants in RNF170 gene cause autosomal recessive complicated HSP with infancy onset. Here, we report an adolescent-onset HSP patient from a consanguineous Chinese family, with lower extremity stiffness, spastic gait, and unstable straight-line walking as the main manifestations. Whole-exome sequencing identifies a novel RNF170 mutation c.190C>T (p.R64*), which co-segregates with the disease in this pedigree. Functional analysis, including quantitative real-time PCR (RT-qPCR) and Western blot, indicates that both the mRNA and protein levels of mutant RNF170 are significantly reduced, which confirms the loss-of-function mechanism. Our study expands the spectrum of RNF170-associated HSP, while the RNF170 protein-involved degradation of the inositol 1,4,5-trisphosphate receptor in neurodegenerative motor neuron disorders deserves further investigation.


Assuntos
Doenças Neurodegenerativas , Paraplegia Espástica Hereditária , Ubiquitina-Proteína Ligases , Adolescente , Humanos , População do Leste Asiático , Paraplegia Espástica Hereditária/genética , Ubiquitina-Proteína Ligases/genética
19.
Glob Chang Biol ; 29(24): 7072-7084, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37795748

RESUMO

Anthropogenic eutrophication is known to impair the stability of aboveground net primary productivity (ANPP), but its effects on the stability of belowground (BNPP) and total (TNPP) net primary productivity remain poorly understood. Based on a nitrogen and phosphorus addition experiment in a Tibetan alpine grassland, we show that nitrogen addition had little impact on the temporal stability of ANPP, BNPP, and TNPP, whereas phosphorus addition reduced the temporal stability of BNPP and TNPP, but not ANPP. Significant interactive effects of nitrogen and phosphorus addition were observed on the stability of ANPP because of the opposite phosphorus effects under ambient and enriched nitrogen conditions. We found that the stability of TNPP was primarily driven by that of BNPP rather than that of ANPP. The responses of BNPP stability cannot be predicted by those of ANPP stability, as the variations in responses of ANPP and BNPP to enriched nutrient, with ANPP increased while BNPP remained unaffected, resulted in asymmetric responses in their stability. The dynamics of grasses, the most abundant plant functional group, instead of community species diversity, largely contributed to the ANPP stability. Under the enriched nutrient condition, the synchronization of grasses reduced the grass stability, while the latter had a significant but weak negative impact on the BNPP stability. These findings challenge the prevalent view that species diversity regulates the responses of ecosystem stability to nutrient enrichment. Our findings also suggest that the ecological consequences of nutrient enrichment on ecosystem stability cannot be accurately predicted from the responses of aboveground components and highlight the need for a better understanding of the belowground ecosystem dynamics.


Assuntos
Ecossistema , Pradaria , Tibet , Nitrogênio , Fósforo , Poaceae
20.
Glob Chang Biol ; 29(3): 841-855, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36272096

RESUMO

Climate warming is changing plant sexual reproduction, having consequences for species distribution and community dynamics. However, the magnitude and direction of plant reproductive efforts (e.g., number of flowers) and success (e.g., number and mass of fruits or seeds) in response to warming have not been well-characterized. Here, we generated a global dataset of simulated warming experiments, consisting of 477 pairwise comparisons for 164 terrestrial species. We found evidence that warming overall decreased fruit number and increased seed mass, but little evidence that warming influenced flower number, fruit mass, or seed number. The warming effects on seed mass were regulated by the pollination type, and insect-pollinated plants exhibited a stronger response to warming than wind-pollinated plants. We found strong evidence that warming increased the mass of seeds for the nondominant species but no evidence of this for the dominant species. There was no evidence that phylogenetic relatedness explained the effects of warming on plant reproductive effort and success. In addition, the effects of warming on flowering onset negatively related to the responses in terms of the number of fruits and seeds to warming, revealing a cascading effect of plant reproductive development. These findings provide the first quantification of the response of terrestrial plant sexual reproduction to warming and suggest that plants may increase their fitness by producing heavier seeds under a warming climate.


Assuntos
Clima , Frutas , Filogenia , Sementes , Polinização/fisiologia , Reprodução , Plantas , Flores
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