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1.
J Am Chem Soc ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38607333

RESUMEN

Unraveling the mechanism of chirality transfer across length scales is crucial to the rational development of functional materials with hierarchical chirality. The key obstacle is the lack of structural information, especially at the mesoscopic level. We report herein the structural identification of helical covalent organic frameworks (heliCOFs) with hierarchical chirality, which integrate molecular chirality, channel chirality, and morphology chirality into one crystalline entity. Specifically, benefiting from the highly ordered structure of heliCOFs, the existence of chiral channels at the mesoscopic level has been confirmed by electron crystallography, and the handedness of these chiral channels has been directly determined through the stereopair imaging technique. Accordingly, the chirality transfer in heliCOFs from microscopic to macroscopic levels could be rationalized with a layer-rotating model that has been supported by both crystal structure analysis and theoretical calculations. Observation of chiral channels in heliCOFs not only provides unprecedented data for the understanding of the chirality transfer process but also sheds new light on the rational construction of highly ordered polymeric materials with hierarchical chirality.

2.
Anal Chem ; 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39185581

RESUMEN

The spatial constraints imposed by the DNA structure have significant implications for the walking efficiency of three-dimensional DNA walkers. However, accurately quantifying and manipulating steric hindrance remains a challenging task. This study presents a steric hindrance-controlled DNA walker utilizing an enzymatic strand displacement amplification (ESDA) strategy for detecting microRNA-21 (miR-21) with tunable dynamic range and sensitivity. The steric hindrance of the DNA walker was precisely manipulated by varying the length of empty bases from 6.5 Što 27.4 Šat the end of the track strand and adjusting the volumetric dimensions of the hairpin structure from 9.13 nm3 to 26.2 nm3 at the terminus of the single-foot DNA walking strand. This method demonstrated a tunable limit of detection for miR-21 ranging from 3.6 aM to 35.6 nM, along with a dynamic range from ∼100-fold to ∼166 000-fold. Impressively, it exhibited successful identification of cancer cells and clinical serum samples with high miR-21 expression. The proposed novel strategy not only enables tunable detection of miRNA through the regulation of steric hindrance but also achieves accurate and quantitative analysis of the steric hindrance effect, promising broader applications in personalized medicine, early disease detection, and drug development.

3.
Anal Chem ; 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38324019

RESUMEN

Cascade molecular events in complex systems are of vital importance for enhancing molecular diagnosis and information processing. However, the conversion of a cascaded biosensing system into a multilayer encrypted molecular keypad lock remains a significant challenge in the development of molecular logic devices. In this study, we present a photocleavable DNA nanotube-based dual-amplified resonance Rayleigh scattering (RRS) system for detecting microRNA-126 (miR-126). The cascading dual-amplification biosensing system provides a multilayer-encrypted prototype with the functionality of a molecular computing cascade keypad lock. RRS signals were greatly amplified by using photocleavable DNA nanotubes and enzyme-assisted strand displacement amplification (SDA). In the presence of miR-126, enzyme-assisted SDA produced numerous identical nucleotide fragments as the target, which were then specifically attached to magnetic beads through the DNA nanotube by using a Y-shaped DNA scaffold. Upon ultraviolet irradiation, the DNA nanotube was released into the solution, resulting in an increase in the intensity of the RRS signal. This strategy demonstrated a low limit of detection (0.16 fM) and a wide dynamic range (1 fM to 1 nM) for miR-126. Impressively, the enzyme-assisted SDA offers a molecular computing model for generating the target pool, which serves as the input element for unlocking the system. By cascading the molecular computing process, we successfully constructed a molecular keypad lock with a multilevel authentication technique. The proposed system holds great potential for applications in molecular diagnosis and information security, indicating significant value in integrating molecular circuits for intelligent sensing.

4.
Brief Bioinform ; 23(1)2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-34524425

RESUMEN

To enable personalized cancer treatment, machine learning models have been developed to predict drug response as a function of tumor and drug features. However, most algorithm development efforts have relied on cross-validation within a single study to assess model accuracy. While an essential first step, cross-validation within a biological data set typically provides an overly optimistic estimate of the prediction performance on independent test sets. To provide a more rigorous assessment of model generalizability between different studies, we use machine learning to analyze five publicly available cell line-based data sets: National Cancer Institute 60, ancer Therapeutics Response Portal (CTRP), Genomics of Drug Sensitivity in Cancer, Cancer Cell Line Encyclopedia and Genentech Cell Line Screening Initiative (gCSI). Based on observed experimental variability across studies, we explore estimates of prediction upper bounds. We report performance results of a variety of machine learning models, with a multitasking deep neural network achieving the best cross-study generalizability. By multiple measures, models trained on CTRP yield the most accurate predictions on the remaining testing data, and gCSI is the most predictable among the cell line data sets included in this study. With these experiments and further simulations on partial data, two lessons emerge: (1) differences in viability assays can limit model generalizability across studies and (2) drug diversity, more than tumor diversity, is crucial for raising model generalizability in preclinical screening.


Asunto(s)
Neoplasias , Algoritmos , Línea Celular , Humanos , Aprendizaje Automático , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Redes Neurales de la Computación
5.
J Org Chem ; 89(11): 8243-8248, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38753315

RESUMEN

Herein we have pioneered an innovative synthetic strategy for the efficient assembly of various heteroarene-condensed benzofuran derivatives, utilizing benzofuran-derived azadienes (BDAs) and quinolines as the starting materials. This method functions with transition-metal catalysis and uses cost-effective formic acid as the reducing agent. Mechanistic investigations indicate that this transformation would involve a [4 + 2] annulation cascade process. This approach demonstrates a high tolerance to various functional groups and yields excellent results.

6.
Appl Microbiol Biotechnol ; 108(1): 293, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38592508

RESUMEN

Kluyveromyces marxianus has become an attractive non-conventional yeast cell factory due to its advantageous properties such as high thermal tolerance and rapid growth. Succinic acid (SA) is an important platform molecule that has been applied in various industries such as food, material, cosmetics, and pharmaceuticals. SA bioproduction may be compromised by its toxicity. Besides, metabolite-responsive promoters are known to be important for dynamic control of gene transcription. Therefore, studies on global gene transcription under various SA concentrations are of great importance. Here, comparative transcriptome changes of K. marxianus exposed to various concentrations of SA were analyzed. Enrichment and analysis of gene clusters revealed repression of the tricarboxylic acid cycle and glyoxylate cycle, also activation of the glycolysis pathway and genes related to ergosterol synthesis. Based on the analyses, potential SA-responsive promoters were investigated, among which the promoter strength of IMTCP2 and KLMA_50231 increased 43.4% and 154.7% in response to 15 g/L SA. In addition, overexpression of the transcription factors Gcr1, Upc2, and Ndt80 significantly increased growth under SA stress. Our results benefit understanding SA toxicity mechanisms and the development of robust yeast for organic acid production. KEY POINTS: • Global gene transcription of K. marxianus is changed by succinic acid (SA) • Promoter activities of IMTCP2 and KLMA_50123 are regulated by SA • Overexpression of Gcr1, Upc2, and Ndt80 enhanced SA tolerance.


Asunto(s)
Kluyveromyces , Ácido Succínico , Kluyveromyces/genética , Perfilación de la Expresión Génica , Transcriptoma
7.
Molecules ; 29(6)2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38542856

RESUMEN

Coordination cages sustained by metal-ligand interactions feature polyhedral architectures and well-defined hollow structures, which have attracted significant attention in recent years due to a variety of structure-guided promising applications. Sulfonylcalix[4]arenes-based coordination cages, termed metal-organic supercontainers (MOSCs), that possess unique multi-pore architectures containing an endo cavity and multiple exo cavities, are emerging as a new family of coordination cages. The well-defined built-in multiple binding domains of MOSCs allow the efficient encapsulation of guest molecules, especially for drug delivery. Here, we critically discuss the design strategy, and, most importantly, the recent advances in research surrounding cavity-specified host-guest chemistry and biomedical applications of MOSCs.

8.
Anal Chem ; 95(36): 13659-13667, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37623910

RESUMEN

Conventional electrochemical detection of microRNA (miRNA) encounters issues of poor sensitivity and fixed dynamic range. Here, we report a DNA tile and invading stacking primer-assisted CRISPR-Cas12a multiple amplification strategy to construct an entropy-controlled electrochemical biosensor for the detection of miRNA with tunable sensitivity and dynamic range. To amplify the signal, a cascade amplification of the CRISPR-Cas12a system along with invading stacking primer signal amplification (ISPSA) was designed to detect trace amounts of miRNA-31 (miR-31). The target miR-31 could activate ISPSA and produce numerous DNAs, triggering the cleavage of the single-stranded linker probe (LP) that connects a methylene blue-labeled DNA tile with a DNA tetrahedron to form a Y-shaped DNA scaffold on the electrode. Based on the decrease of current, miR-31 can be accurately and efficiently detected. Impressively, by changing the loop length of the LP, it is possible to finely tune the entropic contribution while keeping the enthalpic contribution constant. This strategy has shown a tunable limit of detection for miRNA from 0.31 fM to 0.56 pM, as well as a dynamic range from ∼2200-fold to ∼270,000-fold. Moreover, it demonstrated satisfactory results in identifying cancer cells with a high expression of miR-31. Our strategy broadens the application of conventional electrochemical biosensing and provides a tunable strategy for detecting miRNAs at varying concentrations.


Asunto(s)
Sistemas CRISPR-Cas , MicroARNs , Entropía , Sistemas CRISPR-Cas/genética , ADN/genética , Electrodos , MicroARNs/genética
9.
Anal Chem ; 95(29): 11113-11123, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37428145

RESUMEN

Organophosphate pesticides are used in agriculture due to their high effectiveness and low persistence in eradicating insects and pests. However, conventional detection methods encounter the limitation of undesired detection specificity. Thus, screening phosphonate-type organophosphate pesticides (OOPs) from their analogues, phosphorothioate organophosphate pesticides (SOPs), remains a challenge. Here, we reported a d-penicillamine@Ag/Cu nanocluster (DPA@Ag/Cu NCs)-based fluorescence assay to screen OOPs from 21 kinds of organophosphate pesticides, which can be used for logic sensing and information encryption. Acetylthiocholine chloride was enzymatically split by acetylcholinesterase (AChE) to produce thiocholine, which reduced the fluorescence of DPA@Ag/Cu NCs due to the transmission of electrons from DPA@Ag/Cu NCs donor to the thiol group acceptor. Impressively, OOPs acted as an AChE inhibitor and retained the high fluorescence of DPA@Ag/Cu NCs due to the stronger positive electricity of the phosphorus atom. Conversely, SOPs possessed weak toxicity to AChE, which led to low fluorescence intensity. By setting 21 kinds of organophosphate pesticides as the inputs and the fluorescence of the resulting products as the outputs, DPA@Ag/Cu NCs could serve as a fluorescent nanoneuron to construct Boolean logic tree and complex logic circuit for molecular computing. As a proof of concept, by converting the selective response patterns of DPA@Ag/Cu NCs into binary strings, molecular crypto-steganography for encoding, storing, and concealing information was successfully achieved. This study is expected to advance the progress and practical application of nanoclusters in the area of logic detection and information security while also enhancing the relationship between molecular sensors and the world of information.


Asunto(s)
Antígenos de Grupos Sanguíneos , Insecticidas , Nanopartículas del Metal , Organofosfonatos , Plaguicidas , Penicilamina , Acetilcolinesterasa , Compuestos Organofosforados , Colorantes , Organofosfatos , Lógica , Cobre , Plaguicidas/análisis
10.
Anal Chem ; 95(45): 16744-16753, 2023 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-37929302

RESUMEN

Tunable detection of microRNA is crucial to meet the desired demand for sample species with varying concentrations in clinical settings. Herein, we present a DNA walker-based molecular circuit for the detection of miRNA-21 (miR-21) with tunable dynamic ranges and sensitivity levels ranging from fM to pM. The phosphate-activated fluorescence of UiO-66-NH2 metal-organic framework nanoparticles was used as label-free fluorescence tags due to their competitive coordination effect with the Zr atom, which significantly inhibited the ligand-to-metal charge transfer. To achieve a tunable detection performance for miR-21, the ultraviolet sensitive o-nitrobenzyl was induced as a photocleavable linker, which was inserted at various sites between the loop and the stem of the hairpin probe to regulate the DNA strand displacement reaction. The dynamic range can be precisely regulated from 700- to 67,000-fold with tunable limits of detection ranging from 2.5 fM to 36.7 pM. Impressively, a Boolean logic tree and complex molecular circuit were constructed for logic computation and cancer diagnosis in clinical blood samples. This intelligent biosensing method presents a powerful solution for converting complex biosensing systems into actionable healthcare decisions and will facilitate early disease diagnosis.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Estructuras Metalorgánicas , MicroARNs , Nanopartículas , ADN , MicroARNs/genética , Técnicas Biosensibles/métodos , Límite de Detección
11.
Opt Express ; 31(10): 16303-16314, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37157712

RESUMEN

We describe a method for the active control of terahertz (THz) waves using hybrid vanadium dioxide (VO2) periodic corrugated waveguide. Unlike liquid crystals, graphene and semiconductors and other active materials, VO2 exhibits a unique insulator-metal transition characteristic by the electric fields, optical, and thermal pumps, resulting in five orders of magnitude changes in its conductivity. Our waveguide consists of two gold coated plates with the VO2-embedded periodic grooves, which are placed in parallel with the grooves face to face. Simulations show that this waveguide can realize mode switching by changing the conductivity of the embedded VO2 pads, whose mechanism is attributed to the local resonance induced by defect mode. Such a VO2-embedded hybrid THz waveguide is favorable in practical applications such as THz modulators, sensors and optical switches, and provides an innovative technique for manipulating THz waves.

12.
Purinergic Signal ; 19(1): 5-12, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-34378078

RESUMEN

Purinergic signalling adenosine and its A1 receptors have been demonstrated to get involved in the mechanism of acupuncture (needling therapy) analgesia. However, whether purinergic signalling would be responsible for the local analgesic effect of moxibustion therapy, the predominant member in acupuncture family procedures also could trigger analgesic effect on pain diseases, it still remains unclear. In this study, we applied moxibustion to generate analgesic effect on complete Freund's adjuvant (CFA)-induced inflammatory pain rats and detected the purine released from moxibustioned-acupoint by high-performance liquid chromatography (HPLC) approach. Intramuscular injection of ARL67156 into the acupoint Zusanli (ST36) to inhibit the breakdown of ATP showed the analgesic effect of moxibustion was increased while intramuscular injection of ATPase to speed up ATP hydrolysis caused a reduced moxibustion-induced analgesia. These data implied that purinergic ATP at the location of ST36 acupoint is a potentially beneficial factor for moxibustion-induced analgesia.


Asunto(s)
Moxibustión , Ratas , Animales , Ratas Sprague-Dawley , Modelos Animales de Enfermedad , Dolor/tratamiento farmacológico , Puntos de Acupuntura , Analgésicos , Adenosina Trifosfato
13.
Org Biomol Chem ; 21(20): 4191-4194, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37132390

RESUMEN

Fused furans are commonly found units in natural products and medicinal molecules, and methods for their introduction are of fundamental importance. Here we report one-pot cycloadditions of ethynyl indoloxazolidones with 1,3-cyclohexanediones enabled by copper catalysis, leading to a series of functionalized furan derivatives in good yields. This method features mild reaction conditions, high efficiency, and wide substrate scope.

14.
Surg Endosc ; 37(1): 391-401, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35982285

RESUMEN

BACKGROUND: To compare the traditional single-layer and double-layer suture renorrhaphy with modified "Binding" suture renorrhaphy (whole rim of the wound was closed by the all-layer flow suture starting from the parenchyma cut edges to hilum, followed by the final defect closure) in robotic partial nephrectomy (RPN) for treating localized renal cell carcinoma in our large institutional experience. METHODS: We retrospectively reviewed clinical data of 406 consecutive patients who underwent RPN from May 2018 and December 2020 in our center. The demographic and oncologic outcome variables were compared between different renal reconstruction groups and the effect of these suture techniques on renal function outcomes was also evaluated. RESULTS: For the single-layer group, median operative time and warm ischemic time were significantly less than that of the double-layer and "Binding" groups (p < 0.001), while the significantly lower eGFR drop (p = 0.014) was also detected within postoperative 3 months from baseline, but this difference lost its statistical significance from 3th month to the last follow-up. The changes in postoperative creatinine values were clinically insignificant among the three groups. In a sub-analysis over 258 patients with moderate/high nephrometry score, those patients who underwent "Binding" suture had an undifferentiated warm ischemic time, estimated blood loss, and length of hospitalization stay with a decreased risk of Grade III complications (postoperative hemorrhage requiring intervention) and improved renal function recovery during the whole follow-up. CONCLUSION: Single-layer suture renorrhaphy may be associated with better renal functional preservation and could prove to be reliable in patients with low-complexity tumor (RENAL score ≤ 6). Patients with moderate/high-complexity tumor (RENAL score ≥ 7) might represent a subgroup of patients having a functional benefit after "Binding" suture renorrhaphy even in the long-term period.


Asunto(s)
Neoplasias Renales , Procedimientos Quirúrgicos Robotizados , Humanos , Neoplasias Renales/cirugía , Neoplasias Renales/patología , Procedimientos Quirúrgicos Robotizados/métodos , Estudios Retrospectivos , Nefrectomía/métodos , Riñón/cirugía , Riñón/patología , Resultado del Tratamiento
15.
Cell Mol Life Sci ; 79(3): 184, 2022 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-35279748

RESUMEN

The pathogenesis of acute kidney injury (AKI) is associated with the activation of multiple signaling pathways, including Wnt/ß-catenin signaling. However, the mechanism of Wnt/ß-catenin pathway activation in renal interstitial fibroblasts during AKI is unclear. S100 calcium-binding protein A16 (S100A16), a new member of calcium-binding protein S100 family, is a multi-functional signaling factor involved in various pathogenies, including tumors, glycolipid metabolism disorder, and chronic kidney disease (CKD). We investigated the potential participation of S100A16 in Wnt/ß-catenin pathway activation during AKI by subjecting wild-type (WT) and S100A16 knockout (S100A16+/-) mice to the ischemia-reperfusion injury (IRI), and revealed S100A16 upregulation in this model, in which knockout of S100A16 impeded the Wnt/ß-catenin signaling pathway activation and recovered the expression of downstream hepatocyte growth factor (HGF). We also found that S100A16 was highly expressed in Platelet-derived growth factor receptor beta (PDGFRß) positive renal fibroblasts in vivo. Consistently, in rat renal interstitial fibroblasts (NRK-49F cells), both hypoxia/reoxygenation and S100A16 overexpression exacerbated fibroblasts apoptosis and inhibited HGF secretion; whereas S100A16 knockdown or Wnt/ß-catenin pathway inhibitor ICG-001 reversed these changes. Mechanistically, we showed that S100A16 promoted Wnt/ß-catenin signaling activation via the ubiquitylation and degradation of ß-catenin complex members, glycogen synthase kinase 3ß (GSK3ß) and casein kinase 1α (CK1α), mediated by E3 ubiquitin ligase, the HMG-CoA reductase degradation protein 1 (HRD1). Our study identified the S100A16 as a key regulator in the activation of Wnt/ß-catenin signaling pathway in AKI.


Asunto(s)
Lesión Renal Aguda/patología , Caseína Quinasa Ialfa/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Proteínas S100/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Lesión Renal Aguda/metabolismo , Animales , Modelos Animales de Enfermedad , Fibroblastos/citología , Fibroblastos/metabolismo , Riñón/metabolismo , Riñón/patología , Masculino , Ratones , Ratones Noqueados , Unión Proteica , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Ratas , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Proteínas S100/antagonistas & inhibidores , Proteínas S100/deficiencia , Proteínas S100/genética , Ubiquitinación , Vía de Señalización Wnt/efectos de los fármacos , Vía de Señalización Wnt/genética , Proteína X Asociada a bcl-2/metabolismo
16.
Mar Drugs ; 22(1)2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38248650

RESUMEN

Four new compounds, including two ascochlorin-type meroterpenoids acremocholrins A (1) and B (2), one pyridone alkaloid acremopyridone A (7), and one cyclopentenone derivative acremoketene A (12), together with eight known compounds (3-6 and 8-11), were isolated and identified from the hadal trench-derived fungus Acremonium dichromosporum YP-213. Their structures were determined with a detailed spectroscopic analysis of NMR and MS data, NOE analysis, octant rule and quantum chemical calculations of ECD, and NMR (with DP4+ probability analysis). Among the compounds, 7 represent a novel scaffold derived from a pyridone alkaloid by cleavage of the C-16-C-17 bond following oxidation to give a ketone. Compounds 9, 11, and 12 showed potent in vivo anti-inflammatory activity in transgenic zebrafish, while compound 8 exhibited significant proangiogenic activity in transgenic zebrafish.


Asunto(s)
Acremonium , Alcaloides , Pez Cebra , Animales , Antiinflamatorios/farmacología , Hongos , Piridonas
17.
Phytochem Anal ; 34(5): 560-570, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37202874

RESUMEN

INTRODUCTION: Lanqin Oral Liquid (LQL) is a traditional Chinese medicine preparation (TCMP) containing five herbal medicines and has been commonly used for the treatment of pharyngitis and hand-foot-and-mouth disease in clinic. The material basis of LQL has been reported in our previous study, but the contents of the major components and the features of saccharide in LQL are still unclear. OBJECTIVES: This study aimed to establish accurate and rapid methods for the quantification of the major components and profiling of saccharide in LQL. The quantitative results combined with similarity evaluation were applied to improve the quality control of LQL. METHODOLOGY: An ultra-high performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UPLC-QQQ-MS) method was utilised to determine 44 major components. Cosine similarity was used to evaluate the similarities among 20 batches of LQL based on the quantitative results of 44 major components. The physicochemical properties, structure, composition, and contents of saccharide in LQL were detected by a combination of chemical and instrumental analysis. RESULTS: A total of 44 compounds, including flavonoids, iridoid glycosides, alkaloids, and nucleosides, were accurately determined. The 20 batches of LQL were remarkably similar (> 0.95). In addition, d-glucose, galactose, d-glucuronic acid, arabinose, and d-mannose were detected in saccharide of LQL. The contents of saccharide in LQL were 13.52-21.09 mg/ml. CONCLUSIONS: The established methods can be applied for the comprehensive quality control of LQL, including characterisation of saccharide and quantification of representative components. Our study will provide a robust chemical foundation for disclosing the quality markers of its therapeutic effect.


Asunto(s)
Medicamentos Herbarios Chinos , Medicamentos Herbarios Chinos/química , Medicina Tradicional China , Espectrometría de Masas en Tándem/métodos , Flavonoides/análisis , Control de Calidad , Cromatografía Líquida de Alta Presión/métodos
18.
Sensors (Basel) ; 23(8)2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-37112284

RESUMEN

Simultaneous localization and mapping (SLAM) plays a fundamental role in downstream tasks including navigation and planning. However, monocular visual SLAM faces challenges in robust pose estimation and map construction. This study proposes a monocular SLAM system based on a sparse voxelized recurrent network, SVR-Net. It extracts voxel features from a pair of frames for correlation and recursively matches them to estimate pose and dense map. The sparse voxelized structure is designed to reduce memory occupation of voxel features. Meanwhile, gated recurrent units are incorporated to iteratively search for optimal matches on correlation maps, thereby enhancing the robustness of the system. Additionally, Gauss-Newton updates are embedded in iterations to impose geometrical constraints, which ensure accurate pose estimation. After end-to-end training on ScanNet, SVR-Net is evaluated on TUM-RGBD and successfully estimates poses on all nine scenes, while traditional ORB-SLAM fails on most of them. Furthermore, absolute trajectory error (ATE) results demonstrate that the tracking accuracy is comparable to that of DeepV2D. Unlike most previous monocular SLAM systems, SVR-Net directly estimates dense TSDF maps suitable for downstream tasks with high efficiency of data exploitation. This study contributes to the development of robust monocular visual SLAM systems and direct TSDF mapping.

19.
Palliat Support Care ; 21(3): 534-546, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36397274

RESUMEN

OBJECTIVES: This study examined the effects of compassion-based intervention on mental health in cancer patients by using systematic review and meta-analysis of randomized controlled trials (RCTs). METHODS: Eleven bibliographic databases were searched from their earliest data available date up to March 1, 2022. The databases were PubMed, CINAHL, MEDLINE, PsycINFO, WOS, Cochrane, Embase, Scopus, ProQuest Dissertations, Airiti Library, and the National Digital Library of Theses and Dissertations in Taiwan. RESULTS: Ten studies from 2015 to 2021 were included with a total of 771 cancer patients. Most were targeted at women with breast cancer. Brief compassion-based interventions of approximately 30 minutes were conducted by audio file, paper, and web-based self-guided writing prompts. Most were conducted after the completion of active treatment. Anxiety was the most measured outcome. Constructive compassion-based interventions with 4- to 12-week sessions were conducted by a trained facilitator. Most were conducted for patients who had undergone treatment, and depression was the most measured outcome. The meta-analysis indicated that compassion-based interventions had a significant effect of reducing depression and increasing self-compassion. Moderation analysis indicated that constructive intervention showed more benefits of increased self-compassion than brief intervention. Both face-to-face and non-face-to-face web-delivered formats had benefits for increasing self-compassion compared with the control condition. SIGNIFICANCE OF RESULTS: Compassion-based interventions might provide an effective strategy for improving self-compassion and depression among patients with breast cancer. Suggestions for further research and health-care providers follow.


Asunto(s)
Neoplasias de la Mama , Empatía , Femenino , Humanos , Ansiedad/terapia , Trastornos de Ansiedad , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/terapia , Taiwán
20.
Entropy (Basel) ; 25(2)2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36832628

RESUMEN

Hyperspectral-image (HSI) restoration plays an essential role in remote sensing image processing. Recently, superpixel segmentation-based the low-rank regularized methods for HSI restoration have shown outstanding performance. However, most of them simply segment the HSI according to its first principal component, which is suboptimal. In this paper, integrating the superpixel segmentation with principal component analysis, we propose a robust superpixel segmentation strategy to better divide the HSI, which can further enhance the low-rank attribute of the HSI. To better employ the low-rank attribute, the weighted nuclear norm by three types of weighting is proposed to efficiently remove the mixed noise in degraded HSI. Experiments conducted on simulated and real HSI data verify the performance of the proposed method for HSI restoration.

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