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1.
Int J Biol Macromol ; 280(Pt 2): 135735, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39293622

RESUMO

An ideal biomedical hydrogel should imitate natural tissues with high water absorption, high toughness and superior biocompatibility. However, hydrogels constructed from biomolecules such as polysaccharides have low mechanical strength and limited applications. Based on carboxymethyl chitosan (CMCS) and polyacrylamide (PAM), a facile process is presented for preparing double network hydrogels (CMCS/PAM) with improved mechanical properties. According to the systematic characterization, carboxymethyl chitosan and polyacrylamide form a double network hydrogel through hydrogen bonding. The introduction of carboxymethyl chitosan alters the microscopic structure of PAM hydrogel, resulting in a consistent porosity pattern. Hydrogels with double networks exhibit high tensile properties, high stiffness, and good energy dissipation. Furthermore, the hydrogel exhibits effective adhesion to other hydrophilic surfaces. The CMCS/PAM network hydrogels possess excellent properties such as high swelling capacity, injectability, and cellular biocompatibility, making them potentially valuable for biomedical applications.

2.
J Control Release ; 375: 513-523, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39278354

RESUMO

Islet-antigen-specific tolerization is a key goal of experimental immunotherapies for type 1 diabetes. mRNA-based vaccines have demonstrated the feasibility of RNA delivery in inducing antigen tolerance in autoimmune diseases. In this study, mRNA vaccine, encoded tandem glutamic acid decarboxylase 65 (GAD65) epitopes and cholera toxin B subunit (CTB-GADIII), prepared by an in vitro transcription (IVT) system and encapsulated with lipid nanoparticles (LNP), was intramuscularly administered to non-obese diabetic (NOD) and cyclophosphamide (Cy)-NOD mice respectively. The results showed that the mRNA vaccines significantly reduced the incidence rate of type 1 diabetes, delayed the disease progression, improved glucose tolerance, and protected pancreatic morphology and function compared with the controls. Meanwhile, the vaccines also reduced the levels of autoantibodies to glutamic acid decarboxylase (GADA) and insulin (IAA) in the serum. Furthermore, the proportion of CD4+ T helper cell subsets was modulated in the spleen of mice treated with mRNA vaccines, in correspondence with the increased levels of IL-10 and TGF-ß in serum, suggesting the possible mechanism of immune tolerance. This study provides experimental evidence for the application of mRNA vaccines encoding self-antigens in the prevention or treatment of type 1 diabetes.

3.
Adv Mater ; : e2406559, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39295477

RESUMO

Solar-blind ultraviolet (UV) detection plays a critical role in imaging and communication due to its low-noise background, high signal-to-noise ratio, and strong anti-interference capabilities. Detecting the polarization state of UV light can enhance image information and expand the communication dimension. Although polarization detection is explored in visible and infrared light, and applied in fields such as astrophysics and submarine seismic wave detection, solar-blind UV polarization detection remains largely unreported. This is primarily due to the challenge of creating UV polarizers with high transmittance, high extinction ratio, and strong resistance to UV radiation. In this study, it is discovered that the space symmetry breaking of the ß-Ga2O3's b-c plane results in a significant optical absorption dichroic ratio. Leveraging ß-Ga2O3's high solar-blind UV response, a lensless solar-blind UV polarization-sensitive photodetector, circumventing the challenges associated with solar-blind UV polarizers is designed. This photodetector exhibits an exceptionally high intrinsic polarization ratio under 254 nm linearly polarized light, approximately two orders of magnitude higher than other reported nanomaterial-based polarization-sensitive photodetectors. Additionally, it demonstrates significant advantages in solar-blind UV imaging and light communication. This work introduces a novel strategy for solar-blind ultraviolet polarization detection and offers a promising approach for solar-blind light communication.

4.
Angle Orthod ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39195351

RESUMO

A 20-year-old female patient with severe maxillary crowding and skeletal Class III malocclusion was successfully treated using an enhanced pendulum appliance. Camouflage treatment was chosen because the patient refused surgical intervention. Detailed examination and analysis revealed that labial inclination of the maxillary anterior teeth could provide the alignment space necessary after tooth extraction in the maxillary arch but it would not be beneficial esthetically and would increase the moment perpendicular to the tooth long axis as well as increase the risk of bone dehiscence. Therefore, lingual inclination of the mandibular anterior teeth was performed. To create space for aligning the maxillary arch, an enhanced pendulum appliance was utilized, in addition to premolar extraction. The enhanced pendulum appliance had one mesial and one distal helix on each spring, exerting opposing forces in the buccolingual direction and reducing the buccolingual inclination of the molars. In addition, miniscrews were integrated into the Nance arch of the enhanced pendulum appliance to provide skeletal anchorage, minimizing the reciprocal movement of anchorage teeth. This modification not only enhanced control over tooth movement but also improved treatment efficiency. During the entire treatment duration of 17 months, substantial improvement in facial and occlusal aspects were noted. Additionally, the patient retained these positive changes until the subsequent 2-year follow-up period.

5.
Diabetes ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39137121

RESUMO

Excessive macrophage extracellular traps (METs) formation has been implicated in several autoimmune disease pathogenesis; however, its impact on Type 1 Diabetes (T1D) and related mechanisms remains enigmatic. Here, we demonstrated the pivotal role of peptidyl arginine deiminase 4 (PAD4) in driving profuse METs formation and macrophage M1 polarization in intestinal inflammation of non-obese diabetic (NOD) mice. Genetic knockout of PAD4 or adoptive transfer of METs alters the proportion of pro-inflammatory T cells in the intestine, subsequently influencing their migration to the pancreas. Combining RNA sequencing and CUT&Tag analysis we found activated PAD4 transcriptionally regulated CXCL10 expression. This study comprehensively investigated how excessive PAD4-mediated METs formation in the colon increases the aggravation of intestinal inflammation and pro-inflammatory T cells migration, and finally involves T1D progression, suggesting that inhibition METs formation may be a potential therapeutic target for T1D.

6.
Angew Chem Int Ed Engl ; 63(38): e202409948, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-38949953

RESUMO

As a remote and non-contact stimulus, light offers the potential for manipulating the polarization of ferroelectric materials without physical contact. However, in current research, the non-contact write-read (erase) process lacks direct observation through the stable current as output signal. To address this limitation, we investigated the photoinduced polarization switching capabilities of the cyanide-bridged compound [Fe2Co] using visible light, leading to the achievement of rewritable polarization. By subjecting [Fe2Co] crystals to alternating irradiation with 785 nm and 532 nm light, the polarization changes exhibited a distinct square wave pattern, confirming the reliability of the writing and erasing processes. Initialization involved exposing specific crystal units to 532 nm light for storing "1" or "0" information, while reading was accomplished by scanning the units with 785 nm light, resulting in brief current pulses for "1" states and no current signal for "0" states. This research unveils new possibilities for optical storage systems, paving the way for efficient and rewritable data storage and retrieval technologies, such as the next-generation memories.

7.
Angew Chem Int Ed Engl ; 63(39): e202409456, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-38976237

RESUMO

Extremely limited research exploring the photocatalytic potential of main group metals, such as aluminum, gallium, and tin, has been undertaken due to their weak light harvesting properties. This study reports the efficient transformation of sugars to 5-hydroxymethylfurfural (HMF) with high yield employing an original heterogeneous photocatalyst comprising a gallium(III) complex immobilized on an alumina support. Under visible light irradiation, the reaction rate of HMF formation is ~143 times higher than the equivalent thermal reaction performed in the absence of light. The turnover number (TON) of the heterogeneous gallium(III) photocatalyst was as high as 1500, which was ca. two orders of magnitude higher than the TON of the homogeneous gallium(III) system. It is proposed that photoirradiation significantly enhances the Lewis acidity of the catalyst by forming a semi-coordination state between gallium(III) and N-donor ligands, enabling the increased interaction of reactant sugar molecules with gallium(III) active sites. Consistent with this, the photoresponsive coordination of the gallium(III) complex and the abstraction of the hydroxy group by the metal under irradiation with visible light is observed by NMR spectroscopy for the first time. These findings demonstrate that efficient photocatalysts derived from the main group elements can facilitate biomass conversion using visible light.

8.
Heliyon ; 10(13): e33319, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39027590

RESUMO

Background: The expression profiles of differentially expressed genes (DEGs) during pupal development have been demonstrated to be vital in age estimation of forensic entomological study. Here, using forensically important Aldrichina grahami (Diptera: Calliphoridae), we aimed to explore the potential of intrapuparial stage aging and postmortem interval (PMI) estimation based on characterization of successive developmental transcriptomes and gene expression patterns. Methods: We collected A. grahami pupae at 11 successive intrapuparial stages at 20 °C and used the RNA-seq technique to build the transcriptome profiles of their intrapuparial stages. The DEGs were identified during the different intrapuparial stages using comparative transcriptome analysis. The selected marker DEGs were classified and clustered for intrapuparial stage aging and PMI estimation and then further verified for transcriptome data validation. Ultimately, we categorized the overall gene expression levels as the dependent variable and the age of intrapuparial A. grahami as the independent variable to conduct nonlinear regression analysis. Results: We redefined the intrapuparial stages of A. grahami into five key successive substages (I, II, III, IV, and V), based on the overall gene expression patterns during pupal development. We screened 99 specific time-dependent expressed genes (stage-specific DEGs) to determine the different intrapuparial stages based on comparison of the gene expression levels during the 11 developmental intrapuparial stages of A. grahami. We observed that 55 DEGs showed persistent upregulation during the development of intrapuparial A. grahami. We then selected four DEGs (act79b, act88f, up and ninac) which presented consistent upregulation using RT-qPCR (quantitative real-time PCR) analysis, along with consideration of the maximum fold changes during the pupal development. We conducted nonlinear regression analysis to simulate the calculations of the relationships between the expression levels of the four selected DEGs and the developmental time of intrapuparial A. grahami and constructed fitting curves. The curves demonstrated that act79b and ninac showed continuous relatively increasing levels. Conclusions: This study redefined the intrapuparial stages of A. grahami based on expression profiles of developmental transcriptomes for the first time. The stage-specific DEGs and those with consistent tendencies of expression were found to have potential in age estimation of intrapuparial A. grahami and could be supplementary to a more accurate prediction of PMI.

9.
J Med Econ ; 27(1): 919-930, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38953706

RESUMO

AIMS: This study aimed to assess and compare the health care resource utilization (HCRU) and medical cost of metabolic dysfunction-associated steatohepatitis (MASH) by disease severity based on Fibrosis-4 Index (FIB-4) score among US adults in a real-world setting. MATERIALS AND METHODS: This observational cohort study used claims data from the Healthcare Integrated Research Database (HIRD) to compare all-cause, cardiovascular (CV)-related, and liver-related HCRU, including hospitalization, and medical costs stratified by FIB-4 score among patients with MASH (identified by International Classification of Diseases, Tenth Revision, Clinical Modification [ICD-10-CM] code K75.81). Hospitalization and medical costs were compared by FIB-4 score using generalized linear regression with negative binomial and gamma distribution models, respectively, while controlling for confounders. RESULTS: The cohort included a total of 5,104 patients with MASH and comprised 3,162, 1,343, and 599 patients with low, indeterminate, and high FIB-4 scores, respectively. All-cause hospitalization was significantly higher in the high FIB-4 cohort when compared with the low FIB-4 reference after covariate adjustment (rate ratio, 1.63; 95% CI, 1.32-2.02; p < .0001). CV-related hospitalization was similar across all cohorts; however, CV-related costs were 1.26 times higher (95% CI, 1.11-1.45; p < .001) in the indeterminate cohort and 2.15 times higher (95% CI, 1.77-2.62; p < .0001) in the high FIB-4 cohort when compared with the low FIB-4 cohort. Patients with indeterminate and high FIB-4 scores had 2.97 (95% CI, 1.78-4.95) and 12.08 (95% CI, 7.35-19.88) times the rate of liver-related hospitalization and were 3.68 (95% CI, 3.11-4.34) and 33.73 (95% CI, 27.39-41.55) times more likely to incur liver-related costs, respectively (p < .0001 for all). LIMITATIONS: This claims-based analysis relied on diagnostic coding accuracy, which may not capture the presence of all diseases or all care received. CONCLUSIONS: High and indeterminate FIB-4 scores were associated with significantly higher liver-related clinical and economic burdens than low FIB-4 scores among patients with MASH.


MASH is a serious liver disease that can lead to fibrosis, cirrhosis, and other complications. There is a need to understand the impact of disease severity on the burden of MASH. Health care claims data were used to assess the use of medical resources, including hospitalization, and medical costs among patients with 3 different levels of severity of MASH, as assessed via FIB-4 score. FIB-4 is a widely available non-invasive marker of severity. Rates of all-cause, cardiovascular-related and liver-related hospitalization and medical costs were several-fold higher in patients with high disease severity of MASH than those with low disease severity of MASH.


Assuntos
Hospitalização , Revisão da Utilização de Seguros , Índice de Gravidade de Doença , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Adulto , Idoso , Gastos em Saúde/estatística & dados numéricos , Estados Unidos , Fígado Gorduroso/economia , Recursos em Saúde/estatística & dados numéricos , Recursos em Saúde/economia , Estudos Retrospectivos , Doenças Cardiovasculares/economia , Comorbidade , Doenças Metabólicas
10.
Arch Med Sci ; 20(3): 1022-1028, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39050147

RESUMO

Introduction: To investigate the toxicity of combretastatin A4 phosphate (CA4P) hyaluronic acid (HA) gel nanoparticles (HA-CA4P-NPs) in OSCC (oral squamous cell carcinoma). Methods: Toxicity was investigated using fluorescence microscopy, MTT assay, flow cytometry, and OSCC xenograft mouse models. Results: Compared with CA4P, HA-CA4P-NPs generated nearly 10 times more fluorescence in OSCC cells. Cytotoxicity assays showed that HACA4P-NPs were more toxic to SCC-4 cells but not to HNECs. Remarkable necrosis was induced in SCC-4 cells after exposure to HA-CA4P-NPs, and related proteins were upregulated. Furthermore, HA-CA4P-NPs significantly reduced the tumour size. Conclusions: HA-CA4P-NPs improved drug release and delivery, and increased cytotoxicity to cancer cells.

11.
Science ; 384(6700): 1100-1104, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38843317

RESUMO

One-dimensional transition metal dichalcogenides exhibiting an enhanced bulk photovoltaic effect have the potential to exceed the Shockley-Queisser limit efficiency in solar energy harvest within p-n junction architectures. However, the collective output of these prototype devices remains a challenge. We report on the synthesis of single-crystalline WS2 ribbon arrays with defined chirality and coherent polarity through an atomic manufacturing strategy. The chirality of WS2 ribbon was defined by substrate couplings into tunable armchair, zigzag, and chiral species, and the polarity direction was determined by the ribbon-precursor interfacial energy along a coherent direction. A single armchair ribbon showed strong bulk photovoltaic effect and the further integration of ~1000 aligned ribbons with coherent polarity enabled upscaling of the photocurrent.

12.
Int Immunopharmacol ; 136: 112284, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38823179

RESUMO

Cathepsin B (CTSB) and inflammatory cytokines are critical in initiating and developing pancreatitis. Calcineurin, a central calcium (Ca2+)-responsive signaling molecule, mediates acinar cell death and inflammatory responses leading to pancreatitis. However, the detailed mechanisms for regulating CTSB activity and inflammatory cytokine production are unknown. Myricetin (MC) exhibits various biological activities, including anti-inflammatory effects. Here, we aimed to investigate MC effects on pancreatitis and the underlying mechanisms. Prophylactic and therapeutic MC treatment ameliorated the severity of cerulein-, L-arginine-, and PDL-induced acute pancreatitis (AP). The inhibition of CTSB activity by MC was mediated via decreased calcineurin activity and macrophage infiltration, not neutrophils infiltration, into the pancreas. Additionally, calcineurin activity inhibition by MC prevented the phosphorylation of Ca2+/CaM-dependent protein kinase kinase 2 (CaMKK2) during AP, resulting in the inhibition of CaMKIV phosphorylation and adenosine monophosphate-activated protein kinase (AMPK) dephosphorylation. Furthermore, MC reduced nuclear factor-κB activation by modulating the calcineurin-CaMKIV-IKKα/ß-Iκ-Bα and calcineurin-AMPK-sirtuin1 axes, resulting in reduced production of tumor necrosis factor-α, interleukin (IL)-1ß, and IL-6. Our results showed that MC alleviated AP severity by inhibiting acinar cell death and inflammatory responses, suggesting that MC as a calcineurin and CaMKK2 signaling modulator may be a potential treatment for AP.


Assuntos
Calcineurina , Catepsina B , Citocinas , Flavonoides , Camundongos Endogâmicos C57BL , Pancreatite , Animais , Pancreatite/tratamento farmacológico , Pancreatite/imunologia , Pancreatite/patologia , Pancreatite/induzido quimicamente , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Citocinas/metabolismo , Catepsina B/metabolismo , Camundongos , Masculino , Calcineurina/metabolismo , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Ceruletídeo , NF-kappa B/metabolismo , Pâncreas/patologia , Pâncreas/efeitos dos fármacos , Pâncreas/imunologia , Transdução de Sinais/efeitos dos fármacos , Arginina/metabolismo , Modelos Animais de Doenças , Proteínas Quinases Ativadas por AMP/metabolismo
13.
Nano Lett ; 24(22): 6788-6796, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38781093

RESUMO

Currently, the improvement in the processing capacity of traditional processors considerably lags behind the demands of real-time image processing caused by the advancement of photodetectors and the widespread deployment of high-definition image sensors. Therefore, achieving real-time image processing at the sensor level has become a prominent research domain in the field of photodetector technology. This goal underscores the need for photodetectors with enhanced multifunctional integration capabilities than can perform real-time computations using optical or electrical signals. In this study, we employ an innovative p-type semiconductor GaTe0.5Se0.5 to construct a polarization-sensitive wide-spectral photodetector. Leveraging the wide-spectral photoresponse, we realize three-band imaging within a wavelength range of 390-810 nm. Furthermore, real-time image convolutional processing is enabled by configuring appropriate convolution kernels based on the polarization-sensitive photocurrents. The innovative design of the polarization-sensitive wide-spectral GaTe0.5Se0.5-based photodetector represents a notable contribution to the domain of real-time image perception and processing.

14.
Plant J ; 119(3): 1327-1335, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38804053

RESUMO

Ear length (EL) is a key trait that greatly contributes to yield in maize. Although dozens of EL quantitative trait loci have been mapped, very few causal genes have been cloned, and the molecular mechanisms remain largely unknown. Our previous study showed that YIGE1 is involved in sugar and auxin pathways to regulate ear inflorescence meristem (IM) development and thus affects EL in maize. Here, we reveal that YIGE2, the paralog of YIGE1, regulates maize ear development and EL through auxin pathway. Knockout of YIGE2 causes a significant decrease of auxin level, IM length, floret number, EL, and grain yield. yige1 yige2 double mutants had even shorter IM and ears implying that these two genes redundantly regulate IM development and EL. The genes controlling auxin levels are differential expressed in yige1 yige2 double mutants, leading to lower auxin level. These results elucidated the critical role of YIGE2 and the redundancy between YIGE2 and YIGE1 in maize ear development, providing a new genetic resource for maize yield improvement.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Zea mays , Zea mays/genética , Zea mays/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Inflorescência/genética , Inflorescência/crescimento & desenvolvimento , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Locos de Características Quantitativas/genética , Mutação
16.
Adv Sci (Weinh) ; 11(24): e2309781, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38610112

RESUMO

Remote sensing technology, which conventionally employs spectrometers to capture hyperspectral images, allowing for the classification and unmixing based on the reflectance spectrum, has been extensively applied in diverse fields, including environmental monitoring, land resource management, and agriculture. However, miniaturization of remote sensing systems remains a challenge due to the complicated and dispersive optical components of spectrometers. Here, m-phase GaTe0.5Se0.5 with wide-spectral photoresponses (250-1064 nm) and stack it with WSe2 are utilizes to construct a two-dimensional van der Waals heterojunction (2D-vdWH), enabling the design of a gate-tunable wide-spectral photodetector. By utilizing the multi-photoresponses under varying gate voltages, high accuracy recognition can be achieved aided by deep learning algorithms without the original hyperspectral reflectance data. The proof-of-concept device, featuring dozens of tunable gate voltages, achieves an average classification accuracy of 87.00% on 6 prevalent hyperspectral datasets, which is competitive with the accuracy of 250-1000 nm hyperspectral data (88.72%) and far superior to the accuracy of non-tunable photoresponse (71.17%). Artificially designed gate-tunable wide-spectral 2D-vdWHs GaTe0.5Se0.5/WSe2-based photodetector present a promising pathway for the development of miniaturized and cost-effective remote sensing classification technology.

17.
PLoS One ; 19(4): e0300730, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635756

RESUMO

Sarcopenia prevalence and its risk factors in chronic obstructive pulmonary disease (COPD) vary partly due to definition criteria. This systematic review aimed to identify the prevalence and risk factors of sarcopenia in COPD patients. This review was registered in PROSPERO (CRD42022310750). Nine electronic databases were searched from inception to September 1st, 2022, and studies related to sarcopenia and COPD were identified. Study quality was assessed using a validated scale matched to study designs, and a meta-analysis was performed to evaluate sarcopenia prevalence. COPD patients with sarcopenia were compared to those without sarcopenia for BMI, smoking, and mMRC. The current meta-analysis included 15 studies, with a total of 7,583 patients. The overall sarcopenia prevalence was 29% [95% CI: 22%-37%], and the OR of sarcopenia in COPD patients was 1.51 (95% CI: 1.19-1.92). The meta-analysis and systematic review showed that mMRC (OR = 2.02, P = 0.04) and age (OR = 1.15, P = 0.004) were significant risk factors for sarcopenia in COPD patients. In contrast, no significant relationship was observed between sarcopenia and smoking and BMI. Nursing researchers should pay more attention to the symptomatic management of COPD and encourage patients to participate in daily activities in the early stages of the disease.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Sarcopenia , Humanos , Sarcopenia/complicações , Sarcopenia/epidemiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fatores de Risco , Fumar/efeitos adversos , Prevalência
18.
J Am Chem Soc ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38604977

RESUMO

Polar compounds with switchable polarization properties are applicable in various devices such as ferroelectric memory and pyroelectric sensors. However, a strategy to prepare polar compounds has not been established. We report a rational synthesis of a polar CoGa crystal using chiral cth ligands (SS-cth and RR-cth, cth = 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane). Both the original homo metal Co crystal and Ga crystal exhibit a centrosymmetric isostructure, where the dipole moment of metal complexes with the SS-cth ligand and those with the RR-cth ligand are canceled out. To obtain a polar compound, the Co valence tautomeric complex with SS-cth in the homo metal Co crystal is replaced with the Ga complex with SS-cth by mixing Co valence tautomeric complexes with RR-cth and Ga complexes with SS-cth. The CoGa crystal exhibits polarization switching between the pseudononpolar state at a low temperature and the polar state at a high temperature because only Co complexes exhibit changes in electric dipole moment due to metal-to-ligand charge transfer. Following the same strategy, the polarization-switchable CoZn complex was synthesized. The CoZn crystal exhibits polarization switching between the polar state at a low temperature and the pseudononpolar state at a high temperature, which is the opposite temperature dependence to that of the CoGa crystal. These results revealed that the polar crystal can be synthesized by design, using a chiral ligand. Moreover, our method allows for the control of temperature-dependent polarization changes, which contrasts with typical ferroelectric compounds, in which the polar ferroelectric phase typically occurs at low temperatures.

19.
Front Chem ; 12: 1355848, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38456186

RESUMO

Functional molecules have been attracting increasing attention in environmental and physiological studies. In particular, folic acid (FA) could be considered a key factor in estimating, adjusting, and making decisions in the treatment of neurodevelopmental disorders. It promotes the general significance and conceptual for considering FA molecular scientific research detections, which implies related advancement in both of biological structure and detection methods. Among these applications, the FA molecule acts as a coenzyme that incorporates carbon atoms and synthesizes purines and pyrimidines. Therefore, the calibration method has real applications and can be used as a sensing platform and for detection approaches, which conveys the internal relationship between the FA molecule and physiological characterization. This mini review briefly discusses multiple FA application fields and detection pathways and could supplement their utilization in anticipation of the onset of disease.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38498760

RESUMO

Mesh denoising is a crucial technology that aims to recover a high-fidelity 3D mesh from a noise-corrupted one. Deep learning methods, particularly graph convolutional networks (GCNs) based mesh denoisers, have demonstrated their effectiveness in removing various complex real-world noises while preserving authentic geometry. However, it is still a quite challenging work to faithfully regress uncontaminated normals and vertices on meshes with irregular topology. In this paper, we propose a novel pipeline that incorporates two parallel normal-aware and vertex-aware branches to achieve a balance between smoothness and geometric details while maintaining the flexibility of surface topology. We introduce ResGEM, a new GCN, with multi-scale embedding modules and residual decoding structures to facilitate normal regression and vertex modification for mesh denoising. To effectively extract multi-scale surface features while avoiding the loss of topological information caused by graph pooling or coarsening operations, we encode the noisy normal and vertex graphs using four edge-conditioned embedding modules (EEMs) at different scales. This allows us to obtain favorable feature representations with multiple receptive field sizes. Formulating the denoising problem into a residual learning problem, the decoder incorporates residual blocks to accurately predict true normals and vertex offsets from the embedded feature space. Moreover, we propose novel regularization terms in the loss function that enhance the smoothing and generalization ability of our network by imposing constraints on normal consistency. Comprehensive experiments have been conducted to demonstrate the superiority of our method over the state-of-the-art on both synthetic and real-scanned datasets.

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