RESUMO
DNA-induced liquid-liquid phase separation of cyclic GMP-AMP synthase (cGAS) triggers a potent response to detect pathogen infection and promote innate immune signaling. Whether and how pathogens manipulate cGAS-DNA condensation to mediate immune evasion is unknown. We report the identification of a structurally related viral tegument protein family, represented by ORF52 and VP22 from gamma- and alpha-herpesvirinae, respectively, that employs a conserved mechanism to restrict cGAS-DNA phase separation. ORF52/VP22 proteins accumulate into, and effectively disrupt, the pre-formed cGAS-DNA condensation both in vitro and in cells. The inhibition process is dependent on DNA-induced liquid-liquid phase separation of the viral protein rather than a direct interaction with cGAS. Moreover, highly abundant ORF52 proteins carried within viral particles are able to target cGAS-DNA phase separation in early infection stage. Our results define ORF52/VP22-type tegument proteins as a family of inhibitors targeting cGAS-DNA phase separation and demonstrate a mechanism for how viruses overcome innate immunity.
Assuntos
Alphaherpesvirinae , Betaherpesvirinae , DNA , Infecções por Herpesviridae , Evasão da Resposta Imune , Nucleotidiltransferases , Proteínas Estruturais Virais , Alphaherpesvirinae/química , Alphaherpesvirinae/genética , Alphaherpesvirinae/imunologia , Betaherpesvirinae/química , Betaherpesvirinae/genética , Betaherpesvirinae/imunologia , DNA/química , DNA/genética , DNA/imunologia , Células HEK293 , Células HeLa , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/imunologia , Humanos , Imunidade Inata , Nucleotidiltransferases/química , Nucleotidiltransferases/genética , Nucleotidiltransferases/imunologia , Proteínas Estruturais Virais/química , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/imunologiaRESUMO
To use natural gas as a feedstock alternative to coal and oil, its main constituent, methane, needs to be isolated with high purity1. In particular, nitrogen dilutes the heating value of natural gas and is, therefore, of prime importance for removal2. However, the inertness of nitrogen and its similarities to methane in terms of kinetic size, polarizability and boiling point pose particular challenges for the development of energy-efficient nitrogen-removing processes3. Here we report a mixed-linker metal-organic framework (MOF) membrane based on fumarate (fum) and mesaconate (mes) linkers, Zr-fum67-mes33-fcu-MOF, with a pore aperture shape specific for effective nitrogen removal from natural gas. The deliberate introduction of asymmetry in the parent trefoil-shaped pore aperture induces a shape irregularity, blocking the transport of tetrahedral methane while allowing linear nitrogen to permeate. Zr-fum67-mes33-fcu-MOF membranes exhibit record-high nitrogen/methane selectivity and nitrogen permeance under practical pressures up to 50 bar, removing both carbon dioxide and nitrogen from natural gas. Techno-economic analysis shows that our membranes offer the potential to reduce methane purification costs by about 66% for nitrogen rejection and about 73% for simultaneous removal of carbon dioxide and nitrogen, relative to cryogenic distillation and amine-based carbon dioxide capture.
RESUMO
Sickle cell disease (SCD) is a common, severe genetic blood disorder. Current pharmacotherapies are partially effective and allogeneic hematopoietic stem cell transplantation (HSCT) is associated with immune toxicities. Genome editing of patient hematopoietic stem cells (HSCs) to reactivate fetal hemoglobin (HbF) in erythroid progeny offers an alternative potentially curative approach to treat SCD. Although the FDA released guidelines for evaluating genome editing risks, it remains unclear how best to approach pre-clinical assessment of genome-edited cell products. Here we describe rigorous pre-clinical development of a therapeutic γ-globin gene promoter editing strategy that supported an investigational new drug (IND) application cleared by the FDA. We compared γ-globin promoter and BCL11A enhancer targets, identified a potent HbF-inducing lead candidate, and tested our approach in mobilized CD34+ HSPCs from SCD patients. We observed efficient editing, HbF induction to predicted therapeutic levels, and reduced sickling. With single-cell analyses, we defined the heterogeneity of HbF induction and HBG1/HBG2 transcription. With CHANGE-seq for sensitive and unbiased off-target discovery followed by targeted sequencing, we did not detect off-target activity in edited HSPCs. Our study provides a blueprint for translating new ex vivo HSC genome editing strategies towards clinical trials for treating SCD and other blood disorders.
RESUMO
The properties of surface plasmons are notoriously dependent on the supporting materials system. However, new capabilities cannot be obtained until the technique of surface plasmon enabled by advanced two-dimensional materials is well understood. Herein, we present the experimental demonstration of surface plasmon polaritons (SPPs) supported by single-layered MXene flakes (Ti3C2Tx) coating on an optical microfiber and its application as an ammonia gas sensor. Enabled by its high controllability of chemical composition, unique atomistically thin layered structure, and metallic-level conductivity, MXene is capable of supporting not only plasmon resonances across a wide range of wavelengths but also a selective sensing mechanism through frequency modulation. Theoretical modeling and optics experiments reveal that, upon adsorbing ammonia molecules, the free electron motion at the interface between the SiO2 microfiber and the MXene coating is modulated (i.e., the modulation of the SPPs under applied light), thus inducing a variation in the evanescent field. Consequently, a wavelength shift is produced, effectively realizing a selective and highly sensitive ammonia sensor with a 100 ppm detection limit. The MXene supported SPPs open a promising path for the application of advanced optical techniques toward gas and chemical analysis.
RESUMO
It is substantially challenging for non-centrosymmetric (NCS) Hg-based chalcogenides for infrared nonlinear optical (IR-NLO) applications to realize wide band gap (Eg > 3.0 eV) and sufficient phase-matching (PM) second-harmonic-generation intensity (deff > 1.0 × benchmark AgGaS2 ) simultaneously due to the inherent incompatibility. To address this issue, this work presents a diagonal synergetic substitution strategy for creating two new NCS quaternary Hg-based chalcogenides, AEHgGeS4 (AE = Sr and Ba), based on the centrosymmetric (CS) AEIn2 S4 . The derived AEHgGeS4 displays excellent NLO properties such as a wide Eg (≈3.04-3.07 eV), large PM deff (≈2.2-3.0 × AgGaS2 ), ultra-high laser-induced damage threshold (≈14.8-15 × AgGaS2 ), and suitable Δn (≈0.19-0.24@2050 nm), making them highly promising candidates for IR-NLO applications. Importantly, such excellent second-order NLO properties are primarily attributed to the synergistic combination of tetrahedral [HgS4 ] and [GeS4 ] functional primitives, as supported by detailed theoretical calculations. This study reports the first two NCS Hg-based materials with well-balanced comprehensive properties (i.e., Eg > 3.0 eV and deff > 1.0 × benchmark AgGaS2 ) and puts forward a new design avenue for the construction of more efficient IR-NLO candidates.
RESUMO
The nacre-inspired multi-nanolayer structure offers a unique combination of advanced mechanical properties, such as strength and crack tolerance, making them highly versatile for various applications. Nevertheless, a significant challenge lies in the current fabrication methods, which is difficult to create a scalable manufacturing process with precise control of hierarchical structure. In this work, a novel strategy is presented to regulate nacre-like multi-nanolayer films with the balance mechanical properties of stiffness and toughness. By utilizing a co-continuous phase structure and an extensional stress field, the hierarchical nanolayers is successfully constructed with tunable sizes using a scalable processing technique. This strategic modification allows the robust phase to function as nacre-like platelets, while the soft phase acts as a ductile connection layer, resulting in exceptional comprehensive properties. The nanolayer-structured films demonstrate excellent isotropic properties, including a tensile strength of 113.5 MPa in the machine direction and 106.3 MPa in a transverse direction. More interestingly, these films unprecedentedly exhibit a remarkable puncture resistance at the same time, up to 324.8 N mm-1, surpassing the performance of other biodegradable films. The scalable fabrication strategy holds significant promise in designing advanced bioinspired materials for diverse applications.
RESUMO
BACKGROUND: It is currently uncertain whether the combination of a proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor and high-intensity statin treatment can effectively reduce cardiovascular events in patients with acute coronary syndrome (ACS) who have undergone percutaneous coronary intervention (PCI) for culprit lesions. METHODS: This study protocol describes a double-blind, randomized, placebo-controlled, multicenter study aiming to investigate the efficacy and safety of combining a PCSK9 inhibitor with high-intensity statin therapy in patients with ACS following PCI. A total of 1212 patients with ACS and multiple lesions will be enrolled and randomly assigned to receive either PCSK9 inhibitor plus high-intensity statin therapy or high-intensity statin monotherapy. The randomization process will be stratified by sites, diabetes, initial presentation and use of stable (≥4 weeks) statin treatment at presentation. PCSK 9 inhibitor or its placebo is injected within 4 hours after PCI for the culprit lesion. The primary endpoint is the composite of cardiovascular death, myocardial infarction, stroke, re-hospitalization due to ACS or heart failure, or any ischemia-driven coronary revascularization at one-year follow-up between two groups. Safety endpoints mean PCSK 9 inhibitor and statin intolerance. CONCLUSION: The SHAWN study has been specifically designed to evaluate the effectiveness and safety of adding a PCSK9 inhibitor to high-intensity statin therapy in patients who have experienced ACS following PCI. The primary objective of this study is to generate new evidence regarding the potential benefits of combining a PCSK9 inhibitor with high-intensity statin treatment in reducing cardiovascular events among these patients.
RESUMO
To elucidate the degradation mechanism of the CMC-modified MMT composite at aggressive Cu2+ concentrations, large scale molecular dynamics simulation was conducted for CuCl2 concentrations ranging from 0 to 800 mM. Both CMC and MMT followed the Langmuir isotherm for Cu2+ adsorption, and the adsorption capacity of CMC (8.75 mmol/g) was much higher than that of MMT (0.83 mmol/g). Despite the CMC mass ratio being only 4.1%, it adsorbed up to 34.3% of the total adsorbed Cu2+. The Cu2+ attraction ability hierarchy of oxygen-containing functional groups in the CMC is as follows: carboxylic oxygens > alcoholic oxygens > carbinolic oxygens > bridging oxygens > glucose oxygens. Carboxyls were the most effective in chelating and complexing with Cu2+, and they could be intentionally added in artificially synthesized polymer-MMT composites for Cu2+ containment. Formation of the Cu2+ cation bridge between CMC and MMT at aggressive CuCl2 concentrations contributed to the transition of CMC density distribution from unimodality to bimodality and enhanced resistance of polymer elution. As the CuCl2 concentration increased, the stoichiometric ratio between the chelated Cu2+ and carboxylic oxygens increased from 1:2 to 1:1, suggesting the evolution of the Cu2+ chelation mechanism.
RESUMO
The palladium-catalyzed highly regioselective asymmetric allylic alkylation of 3'-indolyl-3-oxindole derivatives with Morita-Baylis-Hillman (MBH) carbonates was developed to facilely construct chiral 3,3'-bisindole derivatives under mild reaction conditions. The regioselectivity (α/γ) of MBH carbonates was efficiently switched in the presence of chiral oxalamide phosphine or spiroketal-based diphosphine/Pd(0) complexes as a chiral catalyst. A series of multifunctional 3,3'-bisindole derivatives with all-carbon quaternary stereogenic centers were obtained in high yields with good to excellent enantio-, diastereo-, and regioselectivity. The present process is endowed with some salient features such as broad substrate scope, N-protecting group-free, excellent stereoselectivity, as well as adjustable regioselectivity.
RESUMO
The transition of China's hydrogen production system to meeting carbon neutrality is considerably uncertain. This study uses a probabilistic framework to assess the transition pathways of hydrogen production in China to meet the goal of carbon neutrality and reveals the key technology selection mechanism. Three strategies for hydrogen production transition were considered: delayed, orderly, and radical, corresponding to the green hydrogen shares between 70 and 95% in 2060. More ambitious strategies tended to result in greater uncertainty of green hydrogen production and introduce higher system costs and cost uncertainty. The different strategies showed notable differences in carbon dioxide (CO2) reduction pathways. The cumulative CO2 emissions of the delayed strategy may reach 3 times that of the radical strategy, and the CO2 reduction uncertainty of the orderly strategy may be twice that of the other strategies. Alkaline electrolyzers were predicted to dominate green hydrogen production until being surpassed by proton exchange membrane electrolyzers (PEM) after 2060. The synergy of the solar-energy storage-PEM technology combination was notable because expensive electrolyzers tended to increase utilization, thereby diluting fixed costs. Our results underscore the importance of studying the impact of uncertainty and technology selection mechanisms on transition pathways.
RESUMO
Low-risk early-stage extranodal natural killer/T-cell lymphoma, nasal type has a favorable outcome with radiation therapy alone, and the addition of chemotherapy shows no survival benefit. Nonetheless, a proportion of patients will relapse or progress, with a dismal outcome, highlighting the need for a novel therapeutic strategy. Promising preliminary findings indicate the efficacy of PD-1/PD-L1 inhibitors in extranodal natural killer/T-cell lymphoma, nasal type, with good toxicity profiles. Here we describe the design of a phase II study (CLCG-NKT-2101), which is evaluating the safety and efficacy of adding anti-PD-1 antibody to the current radiation therapy regimen in low-risk early-stage extranodal natural killer/T-cell lymphoma, nasal type patients. Tislelizumab will be added in an inductive and concurrent way to radiation therapy. The primary end point will be the complete response rate after induction immunotherapy. Clinical trial registration: ClinicalTrials.gov (NCT05149170).
Assuntos
Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma de Células T , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Estadiamento de Neoplasias , Linfoma de Células T/etiologia , Células Matadoras Naturais , Ensaios Clínicos Fase II como AssuntoRESUMO
Background: Radiotherapy is an effective treatment for indolent non-Hodgkin lymphoma (iNHL); however, the optimal radiotherapy dose remains to be determined. We hypothesize that a suitable dose may exist between 4 and 24 Gy. Methods: This prospective multicenter phase II trial intends to recruit 73 sites of iNHL patients, who will receive involved-site radiotherapy of 12 Gy in four fractions. The primary objective is the 6-month clinical complete response rate. Tumor tissue, blood and conjunctival specimens will be collected to identify potential predictive biomarkers. Discussion: The CLCG-iNHL-01 trial will evaluate the efficacy and toxicity of 12 Gy in patients with iNHL and provide information on a novel hypofractionation regimen of low-dose radiotherapy. Clinical Trial Registration: NCT05543070 (ClinicalTrials.gov).
Assuntos
Linfoma não Hodgkin , Humanos , Estudos Prospectivos , Linfoma não Hodgkin/tratamento farmacológico , Resultado do Tratamento , Ensaios Clínicos Fase II como Assunto , Estudos Multicêntricos como AssuntoRESUMO
RN-9893, a TRPV4 antagonist identified by Renovis Inc., showcased notable inhibition of TRPV4 channels. This research involved synthesizing and evaluating three series of RN-9893 analogues for their TRPV4 inhibitory efficacy. Notably, compounds 1b and 1f displayed a 2.9 to 4.5-fold increase in inhibitory potency against TRPV4 (IC50 = 0.71 ± 0.21 µM and 0.46 ± 0.08 µM, respectively) in vitro, in comparison to RN-9893 (IC50 = 2.07 ± 0.90 µM). Both compounds also significantly outperformed RN-9893 in TRPV4 current inhibition rates (87.6 % and 83.2 % at 10 µM, against RN-9893's 49.4 %). For the first time, these RN-9893 analogues were profiled in an in vivo mouse model, where intraperitoneal injections of 1b or 1f at 10 mg/kg notably mitigated symptoms of acute lung injury induced by lipopolysaccharide (LPS). These outcomes indicate that compounds 1b and 1f are promising candidates for acute lung injury treatment.
Assuntos
Lesão Pulmonar Aguda , Benzenossulfonamidas , Sulfonamidas , Canais de Cátion TRPV , Relação Estrutura-Atividade , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/metabolismo , Lesão Pulmonar Aguda/tratamento farmacológico , Sulfonamidas/química , Sulfonamidas/farmacologia , Sulfonamidas/síntese química , Animais , Camundongos , Humanos , Estrutura Molecular , Relação Dose-Resposta a Droga , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Masculino , Camundongos Endogâmicos C57BLRESUMO
Copper contaminant generated from mining and industrial smelting poses potential risks to human health. Biochar, as a low-energy and cost-effective biomaterial, holds value in Cu remediation. Spectral Induced Polarization (SIP) technique is employed in this study to monitor the Cu remediation processes of by biochar in column experiments. Cation exchange at low Cu2+ concentrations and surface complexation at high Cu2+ concentrations are identified as the major mechanisms for copper retention on biochar. The normalized chargeability (mn) from SIP signals linearly decreased (R2 = 0.776) with copper retention under 60 mg/L Cu influent; while mn linearly increases (R2 = 0.907, 0.852) under high 300 and 700 mg/L Cu influents. The characteristic polarizing unit sizes (primarily the pores adsorbing Cu2+) calculated from Schwartz equation match well with experimental results by mercury intrusion porosimetry (MIP). It is revealed that Cu2+ was driven to small pores (â¼3 µm) given high concentration gradient (influent Cu2+ concentration of 700 mg/L). Comparing to activated carbon, biochar is identified as an ideal adsorbent for Cu remediation, given its high adsorption capacity, cost-effectiveness, carbon-sink ability, and high sensitivity to SIP responses - the latter facilitates its performance assessment.
Assuntos
Carvão Vegetal , Cobre , Cobre/química , Carvão Vegetal/química , Adsorção , Recuperação e Remediação Ambiental/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND: To analyse the association among the simultaneous effects of dietary intake, daily life behavioural factors, and frailty outcomes in older Chinese women, we predicted the probability of maintaining physical robustness under a combination of different variables. METHODS: The Fried frailty criterion was used to determine the three groups of "frailty", "pre-frailty", and "robust", and a national epidemiological survey was performed. The three-classification decision tree model was fitted, and the comprehensive performance of the model was evaluated to predict the probability of occurrence of different outcomes. RESULTS: Among the 1,044 participants, 15.9% were frailty and 50.29% were pre-frailty; the overall prevalence first increased and then decreased with age, reaching a peak at 70-74 years of age. Through univariate analysis, filtering, and embedded screening, eight significant variables were identified: staple food, spices, exercise (frequency, intensity, and time), work frequency, self-feeling, and family emotions. In the three-classification decision tree, the values of each evaluation index of Model 3 were relatively average; the accuracy, recall, specificity, precision, and F1 score range were between 75% and 84%, and the AUC was also greater than 0.800, indicating excellent performance and the best interpretability of the results. Model 3 takes exercise time as the root node and contains 6 variables and 10 types, suggesting the impact of the comprehensive effect of these variables on robust and non-robust populations (the predicted probability range is 6.67-93.33%). CONCLUSION: The combined effect of these factors (no exercise or less than 0.5 h of exercise per day, occasional exercise, exercise at low intensity, feeling more tired at work, and eating too many staple foods (> 450 g per day) are more detrimental to maintaining robustness.
Assuntos
Fragilidade , Humanos , Feminino , Idoso , Fragilidade/diagnóstico , Idoso Fragilizado , Dieta , Exercício Físico , Estilo de VidaRESUMO
Air guns, particularly BB (ball-bearing or bullet ball) guns, have gained significant power and velocity over the last few decades. More than 145,000 pediatric patients suffered injuries attributed to air guns in the United States between 2001 and 2011, and approximately 22,000 pediatric emergency department visits are attributed to air gun-related injuries annually (Hyak et al., 2020 [1]). This study aims to describe an effective surgical technique in addressing maxillofacial injuries caused by BB gun projectiles in the pediatric population. We present a detailed surgical approach for endoscopic endonasal retrieval of a transorbital projectile in a 13-year-old male who sustained a maxillofacial BB gun injury, with the goal of restoring sinonasal function in a minimally invasive fashion.
Assuntos
Armas de Fogo , Ferimentos por Arma de Fogo , Masculino , Humanos , Criança , Estados Unidos , Adolescente , Ferimentos por Arma de Fogo/diagnóstico por imagem , Ferimentos por Arma de Fogo/cirurgia , Ferimentos por Arma de Fogo/epidemiologia , Multimídia , Serviço Hospitalar de EmergênciaRESUMO
As the mainstay of healthcare, the job satisfaction of medical staff deserves attention. This study aimed to explore the correlation between the perception of the high-performance work system (P-HPWS) and job satisfaction of medical staff in public hospitals and to further investigate the mediating effect of self-efficacy. From November 2019 to January 2020, a cross-sectional survey on working doctors and nurses was conducted in five tertiary public hospitals in China. A total of 520 participants were surveyed. The P-HPWS, job satisfaction, and self-efficacy were assessed using the 25-item self-administered scale, six-item job satisfaction questionnaire, and the General Self-Efficacy Scale, respectively. Linear regression and mediation effects models were used to identify the associations between primary variables. The results showed a significant positive correlation between P-HPWS and job satisfaction (P < 0.01), while self-efficacy played a mediating role between P-HPWS and job satisfaction. This finding reveals the benefits of improving employees' P-HPWS and self-efficacy on their job satisfaction, and that hospitals can improve their management systems by implementing and refining HPWS.
Assuntos
Atenção à Saúde , Autoeficácia , Humanos , Estudos Transversais , Inquéritos e Questionários , Corpo Clínico , Hospitais Públicos , Satisfação no EmpregoRESUMO
Cryptococcus neoformans (C. neoformans) is a pathogenic fungus that can cause life-threatening meningitis, particularly in individuals with compromised immune systems. The current standard treatment involves the combination of amphotericin B and azole drugs, but this regimen often leads to inevitable toxicity in patients. Therefore, there is an urgent need to develop new antifungal drugs with improved safety profiles. We screened antimicrobial peptides from the hemolymph transcriptome of Blaps rhynchopetera (B. rhynchopetera), a folk Chinese medicine. We found an antimicrobial peptide named blap-6 that exhibited potent activity against bacteria and fungi. Blap-6 is composed of 17 amino acids (KRCRFRIYRWGFPRRRF), and it has excellent antifungal activity against C. neoformans, with a minimum inhibitory concentration (MIC) of 0.81 µM. Blap-6 exhibits strong antifungal kinetic characteristics. Mechanistic studies revealed that blap-6 exerts its antifungal activity by penetrating and disrupting the integrity of the fungal cell membrane. In addition to its direct antifungal effect, blap-6 showed strong biofilm inhibition and scavenging activity. Notably, the peptide exhibited low hemolytic and cytotoxicity to human cells and may be a potential candidate antimicrobial drug for fungal infection caused by C. neoformans.
Assuntos
Antifúngicos , Peptídeos Antimicrobianos , Besouros , Cryptococcus neoformans , Testes de Sensibilidade Microbiana , Cryptococcus neoformans/efeitos dos fármacos , Animais , Antifúngicos/farmacologia , Antifúngicos/química , Besouros/microbiologia , Besouros/efeitos dos fármacos , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Humanos , Biofilmes/efeitos dos fármacos , Sequência de AminoácidosRESUMO
Quercus gilva, an evergreen tree species in Quercus section Cyclobalanopsis, is an ecologically and economically valuable species in subtropical regions of East Asia. Predicting the impact of climate change on potential distribution of Q. gilva can provide a scientific basis for the conservation and utilization of its genetic resources, as well as for afforestation. In this study, 74 distribution records of Q. gilva and nine climate variables were obtained after data collection and processing. Current climate data downloaded from WorldClim and future climate data predicted by four future climate scenarios (2040s SSP1-2.6, 2040s SSP5-8.5, 2060s SSP1-2.6, and 2060s SSP5-8.5) mainly based on greenhouse gases emissions of distribution sites were used in MaxEnt model with optimized parameters to predict distribution dynamics of Q. gilva and its response to climate change. The results showed that the predicted current distribution was consistent with natural distribution of Q. gilva, which was mainly located in Hunan, Jiangxi, Zhejiang, Fujian, Guizhou, and Taiwan provinces of China, as well as Japan and Jeju Island of South Korea. Under current climate conditions, precipitation factors played a more significant role than temperature factors on distribution of Q. gilva, and precipitation of driest quarter (BIO17) is the most important restriction factor for its current distribution (contribution rate of 57.35%). Under future climate conditions, mean temperature of driest quarter (BIO9) was the essential climate factor affecting future change in potential distribution of Q. gilva. As the degree of climatic anomaly increased in the future, the total area of predicted distribution of Q. gilva showed a shrinking trend (decreased by 12.24%-45.21%) and Q. gilva would migrate to high altitudes and latitudes. The research results illustrated potential distribution range and suitable climate conditions of Q. gilva, which can provide essential theoretical references for the conservation, development, and utilization of Q. gilva and other related species.
Assuntos
Gases de Efeito Estufa , Quercus , Mudança Climática , China , Taiwan , EcossistemaRESUMO
In the deep-ultraviolet (DUV) region, nonlinear optical (NLO) crystals must meet stringent requirements, including a large optical band gap and sufficient second harmonic generation (SHG) response. Typically, these criteria are fulfilled by borates, carbonates and nitrates containing π-conjugated groups. In contrast, sulfates and phosphates, with polarizabilities significantly smaller than those of π-conjugated groups, struggle to achieve similar performance. Here, we present the discovery of Mg2PO4Cl, a magnesium-based phosphate, identified from over 10,000 phosphates based on a polar-axial-symmetry screening strategy, which exhibits the highest SHG response (5.2 × KH2PO4 (KDP)) with phase-matching ability among non-π-conjugated DUV transparent NLO crystals. This compound belongs to the Pna21 space group, with [PO4] units consistently aligned along the 21 screw axis and glide planes throughout its crystal structure. Theoretical calculations attribute its remarkable SHG effect to the orderly arrangement of heteroanionic [MgO5Cl] and [MgO4Cl2] polyhedra alongside isolated [PO4] tetrahedra, supported by Berry phase analysis. Furthermore, a crystallographic structure analysis of phosphates and sulfates with significant SHG effects validates the effectiveness of our screening strategy. These findings offer valuable insights into the origins of NLO effects in non-π-conjugated compounds from both a material design and structural chemistry perspective, inspiring future efforts to revitalize DUV phosphates.