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1.
Wideochir Inne Tech Maloinwazyjne ; 19(1): 91-99, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38974766

RESUMO

Introduction: Both hook-wire (HW) and anchored needle (AN) techniques can be used for preoperative computed tomography (CT)-guided localization for pulmonary nodules (PNs). But the outcomes associated with these two materials remain unclear. Aim: To assess the relative safety and efficacy of preoperative CT-guided HW and AN localization for PNs. Material and methods: This was a retrospective analysis of data collected from two institutions. Consecutive patients with PNs between January 2020 and December 2021 who underwent preoperative CT-guided HW or AN localization followed by video-assisted thoracoscopic surgery (VATS) procedures were included in these analyses, which compared the safety and clinical efficiency of these two localization strategies. Results: In total, 98 patients (105 PNs) and 93 patients (107 PNs) underwent CT-guided HW and AN localization procedures, respectively. The HW and AN groups exhibited similar rates of successful PN localization (95.2% vs. 99.1%, p = 0.117), but the dislodgement rate in the HW group was significantly higher than that for the AN group (4.8% vs. 0.0%, p = 0.029). The mean pain score of patients in the HW group was significantly higher than that for the AN group (p = 0.001). HW and AN localization strategies were associated with comparable pneumothorax (21.4% vs. 16.1%, p = 0.349) and pulmonary hemorrhage (29.6% vs. 23.7%, p = 0.354) rates. All patients other than 1 individual in the HW group successfully underwent VATS-guided limited resection. Conclusions: These data suggest that AN represents a safe, well-tolerated, feasible preoperative localization strategy for PNs that may offer value as a replacement for HW localization.

2.
Int J Surg Case Rep ; 120: 109836, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38824740

RESUMO

INTRODUCTION: Midgut volvulus in adults based on congenital malrotation, which required emergency surgery, may occur under the stimulation of adverse factors and is rare and easy to be misdiagnosed. PRESENTATION OF CASE: A young male was taken to the emergency room of a local hospital after six hours abdominal pain. Computed tomography (CT) shows intestinal volvulus and exploratory laparotomy was performed. Postoperative CT revealed remission of small intestinal torsion and congenital malrotation of the midgut. The patient vomited frequently within 48 h after the surgery, and was transferred to our hospital for conservative treatment. After 4 days of conservative treatment, the vomiting symptoms were relieved at first, but worsened again after a liquid diet. CT showed complete duodenal obstruction and exploratory laparotomy was performed again. Congenital malrotation was found, which resulted in midgut volvulus and duodenal obstruction due to anomalous fixation of the mesentery. The bowel was placed in normal anatomical position, and the mesentery was sutured to the posterior abdominal wall. The patient was followed up for 24 months with no complaints. DISCUSSION: Due to the rare incidence and atypical pain clinical manifestations, it is difficult for the congenital malrotation in adults to be diagnosed. Midgut volvulus in adults with malrotation is even rarer and requires emergency operation, and may be misdiagnosed. CONCLUSION: Midgut volvulus with midgut malrotation is very rare in adults. Exploratory laparotomy must be careful to reduce misdiagnosis and recurrence of volvulus.

3.
Biol Res Nurs ; : 10998004241260894, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38865156

RESUMO

The purpose of this study was to explore whether prenatal gut microbiota (GM) and its functions predict the development of offspring temperament. A total of 53 mothers with a 1-year-old child and 41 mothers with a 2-year-old child were included in this study using a mother-infant cohort from central China. Maternal fecal samples collected during the third trimester were analyzed using 16S rRNA V3-V4 gene sequences. Temperament of the child was measured by self-reported data according to the primary caregiver. The effects of GM in mothers on offspring's temperament were evaluated using multiple linear regression models. The results demonstrated that the alpha diversity index Simpson of prenatal GM was positively associated with the activity level of offspring at 1 year (adj. P = .036). Bifidobacterium was positively associated with high-intensity pleasure characteristics of offspring at 1 year (adj. P = .031). Comparatively, the presence of Bifidobacterium found in the prenatal microbiome was associated with low-intensity pleasure characteristics in offspring at 2 years (adj. P = .031). There were many significant associations noted among the functional pathways of prenatal GM and temperament of offspring at 2 years. Our findings support the maternal-fetal GM axis in the setting of fetal-placental development with subsequent postnatal neurocognitive developmental outcomes, and suggest that early childhood temperament is in part associated with specific GM in the prenatal setting.

4.
Micromachines (Basel) ; 15(6)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38930734

RESUMO

As the thickness of an ultra-thin flattened heat pipe (UTHP) decreases, the fabrication difficulty increases exponentially, and the thermal performance deteriorates rapidly. In this study, three types of composite wicks were developed for UTHPs with a 0.6 mm thickness: copper foam and mesh wick (CFMW), two layers of different mesh wick (TDMW), and three layers of the same mesh wick (TSMW). The startup and steady-state performances of the UTHPs with liquid filling ratios of 60% to 120% were investigated. The findings indicated that the CFMW UTHP with a filling ratio of 100% exhibited the best startup performance, with the highest equilibrium temperature of 58.37 °C. The maximum heat transport capacities of the CFMW, TDMW, and TSMW UTHP samples were 9, 8, and 8.5 W, respectively, at their corresponding optimum filling ratios of 110%, 90%, and 100%. The CFMW UTHP exhibited the lowest evaporation and condensation thermal resistances of 0.151 and 0.189 K/W, respectively, which were 24.67% and 41.85% lower than those of the TSMW UTHP. CFMW can be used to improve the thermal performance of UTHPs. This study provides important guidelines for the structural design, fabrication technology, and performance improvement of high-performance UTHPs used in portable electronic devices.

5.
Arch Gerontol Geriatr ; 125: 105504, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38870707

RESUMO

BACKGROUND: Both we and others have found that RBC counts are significantly lower in older compared to younger. However, when gender is factored in, a significant age-related decrease of RBC counts is observed only in men but not in women. METHODS: qPCR and confocal microscopy were used to detect the presence of mtDNA in RBCs. Flow cytometry and specific inhibitors were used to determine how RBCs uptake cf-mtDNA. The peripheral blood was collected from 202 young adults and 207 older adults and RBC and plasma were isolated. The levels of TLR9+RBCs and apoptotic RBCs after uptake of cf-mtDNA by RBCs were measured by flow cytometry. The kit detects changes in SOD and MDA levels after cf-mtDNA uptake by RBCs. Young RBCs (YR) and old RBCs (OR) from single individuals were separated by Percoll centrifugation. RESULTS: We found a significant decrease in RBC counts and a significant increase in the RDW with aging only in men. We also found that significantly elevated mtDNA content in RBCs was observed only in men during aging and was not found in women. Further studies demonstrated that RBCs could take up cf-mtDNA via TLR9, and the uptake of mtDNA might lead to a decrease in the RBC number and an increase in RDW due to an increase of oxidative stress. CONCLUSIONS: The RBC mtDNA content might be a potential marker of RBC aging and the elevated RBC mtDNA content might be the cause of faster senescence in males than females.


Assuntos
Envelhecimento , DNA Mitocondrial , Eritrócitos , Estresse Oxidativo , Humanos , Estresse Oxidativo/fisiologia , DNA Mitocondrial/sangue , Masculino , Feminino , Eritrócitos/metabolismo , Idoso , Adulto , Envelhecimento/fisiologia , Envelhecimento/sangue , Fatores Sexuais , Citometria de Fluxo , Receptor Toll-Like 9/metabolismo , Adulto Jovem , Contagem de Eritrócitos , Pessoa de Meia-Idade , Senescência Celular/fisiologia
7.
J Stomatol Oral Maxillofac Surg ; : 101896, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38685356

RESUMO

In this study, we aimed to provide guidance for selecting bone grafting materials in cases of alveolar clefts. Twenty-nine patients with unilateral complete alveolar clefts were categorized into three groups based on the bone grafting material used: Group A (iliac bone block grafts), Group B (iliac cancellous bone grafts), and Group C (chin bone block grafts). Cone-beam computed tomography (CBCT) data were analyzed using Mimics 19.0 software. Results showed that Group A had the highest bone formation rate, with significant differences observed between Groups A and B, as well as between Groups B and C. Group A and Group C had the highest proportion of Type I in volume assessment, while Group B had the highest proportion of Type III, Significant differences were observed in the distribution of volume assessment scores among the three groups. Bone height measurement results indicated that buccal-side measurement points had a higher proportion of Type I bone height than palatal-side measurement points. Bone width measurement results showed that Type I bone width was highest in Group C, while Type IV bone width was highest in Group B. Significant differences were observed in the distribution of implanted bone width among the three groups. Total grafting scores indicated that Types A and D were predominant in Groups A and C, while Group B had the highest proportion of Type D. Significant differences were observed in the distribution of total grafting scores among the three groups. The comprehensive evaluation method provides accurate assessment of alveolar cleft bone grafting outcomes and is applicable in clinical settings. Based on the results, we consider both iliac bone blocks and chin bone blocks as suitable materials for alveolar cleft bone grafting. Grafting material selection should consider preoperative gap volume measured using CBCT, required bone quantity, donor site complications, and overall clinical needs.

8.
Cell Commun Signal ; 22(1): 202, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566036

RESUMO

Non-small cell lung cancer (NSCLC) is a prevalent form of lung cancer. Patients with advanced NSCLC are currently being treated with various therapies, including traditional radiotherapy, chemotherapy, molecular targeted therapies and immunotherapy. However, a considerable proportion of advance patients who cannot benefit from them. Consequently, it is essential to identify a novel research target that offers an encouraging perspective. The stimulator of interferon genes (STING) has emerged as such a target. At present, it is confirmed that activating STING in NSCLC tumor cells can impede the proliferation and metastasis of dormant tumor cells. This review focuses on the role of STING in NSCLC treatment and the factors influencing its activation. Additionally, it explores the correlation between STING activation and diverse therapy modalities for NSCLC, such as radiotherapy, chemotherapy, molecular targeted therapies and immunotherapy. Furthermore, it proposes the prospect of innovative therapy methods involving nanoparticles, with the aim of using the features of STING to develop more strategies for NSCLC therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Humanos , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Imunoterapia , Terapia de Alvo Molecular
9.
Small Methods ; : e2400304, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577823

RESUMO

Intracerebral hemorrhage (ICH) represents one of the most severe subtypes of stroke. Due to the complexity of the brain injury mechanisms following ICH, there are currently no effective treatments to significantly improve patient functional outcomes. Curcumin, as a potential therapeutic agent for ICH, is limited by its poor water solubility and oral bioavailability. In this study, mPEG-PCL is used to encapsulate curcumin, forming curcumin nanoparticles, and utilized the intranasal administration route to directly deliver curcumin nanoparticles from the nasal cavity to the brain. By inhibiting pro-inflammatory neuroinflammation of microglia following ICH in mice, reprogramming pro-inflammatory microglia toward an anti-inflammatory function, and consequently reducing neuronal inflammatory death and hematoma volume, this approach improved blood-brain barrier damage in ICH mice and promoted the recovery of neurological function post-stroke. This study offers a promising therapeutic strategy for ICH to mediate neuroinflammatory microenvironments.

10.
Small ; : e2400630, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38431937

RESUMO

Doxorubicin (DOX) is widely used as a chemotherapeutic agent for both hematologic and solid tumors and is a reasonable candidate for glioma treatment. However, its effectiveness is hindered by significant toxicity and drug resistance. Moreover, the presence of the blood-brain barrier (BBB) brings a crucial challenge to glioma therapy. In response, a GSH-responsive and actively targeted nanoprodrug delivery system (cRGD/PSDOX-Cur@NPs) are developed. In this system, a disulfide bond-bridged DOX prodrug (PEG-SS-DOX) is designed to release specifically in the high glutathione (GSH) tumor environment, markedly reducing the cardiotoxicity associated with DOX. To further address DOX resistance, curcumin, serving as a P-glycoprotein (P-gp) inhibitor, effectively increased cellular DOX concentration. Consequently, cRGD/PSDOX-Cur@NPs exhibited synergistic anti-tumor effects in vitro. Furthermore, in vivo experiments validated the superior BBB penetration and brain-targeting abilities of cRGD/PSDOX-Cur@NPs, showcasing the remarkable potential for treating both subcutaneous and orthotopic gliomas. This research underscores that this nanoprodrug delivery system presents a novel approach to inhibiting glioma while addressing resistance and systemic toxicity.

11.
CNS Neurosci Ther ; 30(3): e14674, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38468130

RESUMO

BACKGROUND: Long-term non-traumatic noise exposure, such as heavy traffic noise, can elicit emotional disorders in humans. However, the underlying neural substrate is still poorly understood. METHODS: We exposed mice to moderate white noise for 28 days to induce anxiety-like behaviors, measured by open-field, elevated plus maze, and light-dark box tests. In vivo multi-electrode recordings in awake mice were used to examine neuronal activity. Chemogenetics were used to silence specific brain regions. Viral tracing, immunofluorescence, and confocal imaging were applied to define the neural circuit and characterize the morphology of microglia. RESULTS: Exposure to moderate noise for 28 days at an 85-dB sound pressure level resulted in anxiety-like behaviors in open-field, elevated plus maze, and light-dark box tests. Viral tracing revealed that fibers projecting from the auditory cortex and auditory thalamus terminate in the lateral amygdala (LA). A noise-induced increase in spontaneous firing rates of the LA and blockade of noise-evoked anxiety-like behaviors by chemogenetic inhibition of LA glutamatergic neurons together confirmed that the LA plays a critical role in noise-induced anxiety. Noise-exposed animals were more vulnerable to anxiety induced by acute noise stressors than control mice. In addition to these behavioral abnormalities, ionized calcium-binding adaptor molecule 1 (Iba-1)-positive microglia in the LA underwent corresponding morphological modifications, including reduced process length and branching and increased soma size following noise exposure. Treatment with minocycline to suppress microglia inhibited noise-associated changes in microglial morphology, neuronal electrophysiological activity, and behavioral changes. Furthermore, microglia-mediated synaptic phagocytosis favored inhibitory synapses, which can cause an imbalance between excitation and inhibition, leading to anxiety-like behaviors. CONCLUSIONS: Our study identifies LA microglial activation as a critical mediator of noise-induced anxiety-like behaviors, leading to neuronal and behavioral changes through selective synapse phagocytosis. Our results highlight the pivotal but previously unrecognized roles of LA microglia in chronic moderate noise-induced behavioral changes.


Assuntos
Ansiedade , Microglia , Humanos , Camundongos , Animais , Ansiedade/etiologia , Ansiedade/psicologia , Neurônios , Sinapses , Tonsila do Cerebelo
12.
Cell Metab ; 36(4): 778-792.e10, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38378000

RESUMO

Here, we identify a subset of vascular pericytes, defined by expression of platelet-derived growth factor receptor beta (PDGFR-ß) and G-protein-coupled receptor 91 (GPR91), that promote tumorigenesis and tyrosine kinase inhibitors (TKIs) resistance by functioning as the primary methionine source for cancer stem cells (CSCs) in clear cell renal cell carcinoma (ccRCC). Tumor-cell-derived succinate binds to GPR91 on pericyte to activate autophagy for methionine production. CSCs use methionine to create stabilizing N6-methyladenosine in ATPase-family-AAA-domain-containing 2 (ATAD2) mRNA, and the resulting ATAD2 protein complexes with SRY-box transcription factor 9 to assemble super enhancers and thereby dictate its target genes that feature prominently in CSCs. Targeting PDGFR-ß+GPR91+ pericytes with specific GRP91 antagonists reduce intratumoral methionine level, eliminate CSCs, and enhance TKIs sensitivity. These results unraveled the mechanisms by which PDGFR-ß+GPR91+ pericytes provide supportive niche for CSCs and could be used to develop targets for treating ccRCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Pericitos/metabolismo , Carcinoma de Células Renais/patologia , Metionina/metabolismo , Racemetionina/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Neoplasias Renais/patologia , Células-Tronco Neoplásicas/metabolismo , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Proteínas de Ligação a DNA/metabolismo
13.
iScience ; 27(3): 109046, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38384848

RESUMO

Poor endometrial receptivity results in embryo implantation failure. Acquisition of endometrial receptivity involves substantial structural alterations in the cytoskeleton and plasma membrane of epithelial cells, which facilitate embryo adhesion. However, the underlying molecular mechanism remains largely unknown. In this study, we identified that α-actinin-1 (ACTN1) was significantly downregulated in the mid-secretory phase of the endometrium compared with other phases; however, ACTN1 significantly increased in women with recurrent implantation failure (RIF). In Ishikawa and human endometrial epithelial cells (HEECs), ACTN1 overexpression significantly decreased NEBL levels, enhanced F-actin fiber levels, and caused a notable impairment in blastocyst adhesion, which mimicked the process of embryo adhesion. However, NEBL overexpression notably restored adhesion. Moreover, NEBL expression was reduced in patients with RIF compared with that in controls. Finally, our data showed that ACTN1 upregulation impaired endometrial receptivity in women with RIF, possibly by regulating NEBL expression and subsequent cell-adhesion capability.

14.
Langmuir ; 40(4): 2120-2129, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38215485

RESUMO

In this study, a custom rutile titanium dioxide (TiO2) photocatalyst with a single exposed surface was utilized to investigate the facet-dependent photocatalytic mechanism of toluene. The degradation of toluene was dynamically monitored using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) technology coupled with theoretical calculations. The findings demonstrated that the photocatalytic degradation rate on the TiO2 (001) surface was nearly double that observed on the TiO2 (110) surface. This remarkable enhancement can be attributed to the heightened stability in the adsorption of toluene molecules and the concurrent reduction in the energy requirement for the ring-opening process of benzoic acid on the TiO2 (001) surface. Moreover, the TiO2 (001) surface generated a greater number of reactive oxygen species (ROS), thereby promoting the separation of photogenerated charge carriers and concurrently diminishing their recombination rates, amplifying the efficiency of photocatalysis. This research provides an innovative perspective for a more comprehensive understanding of the photocatalytic degradation mechanism of TiO2 and presents promising prospects for significant applications in environmental purification and energy fields.

15.
Immun Inflamm Dis ; 12(1): e1119, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38270320

RESUMO

BACKGROUNDS: The immunomodulatory properties of human chorionic gonadotrophin (hCG) have been identified to be critical for successful pregnancy. However, the effects of hCG on peripheral γδT cells during early pregnancy have not been reported previously. METHODS: We cocultured the purified γδT cells and peripheral blood mononuclear cells (PBMCs) with early pregnancy-relevant hCG concentrations and investigated the changes in the immune functional characteristics of γδT cells via flow cytometry assays. RESULTS: The ratios of CD69+ and IL-10+ γδT cells were increased in early pregnant women compared to nonpregnant women. γδT cells expressed low levels of the mannose receptor (CD206) instead of the classical hCG/LH receptor for hCG. The direct treatment of purified γδT cells with early pregnancy-relevant hCG concentrations may have no significant effects on their immune functions. Interestingly, when PBMCs were treated with the same broad range of hCG concentrations, the ratios of CD69+ and IL-10+ γδT cells to total γδT cells were significantly increased. CONCLUSION: Certain early pregnancy-relevant hCG concentrations could enhance the ratios of peripheral CD69+ and IL-10+ γδT cells, contributing to the activation of γδT cells and immunological tolerance during early pregnancy. However, these affects may not be strongly mediated by direct ligand-receptor interactions and they may highly depend on immune microenvironment. Our novel observations propose a perspective into the endocrine-immune dialog that exists between the fetus and maternal immune cells.


Assuntos
Gonadotropina Coriônica , Interleucina-10 , Leucócitos Mononucleares , Gravidez , Feminino , Humanos , Gravidez/imunologia , Bioensaio , Técnicas de Cocultura , Gonadotropina Coriônica/fisiologia
16.
RSC Adv ; 14(2): 872-877, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38174286

RESUMO

Surface modification of cellulose acetate filter rods with low temperature plasma was performed to explore the retention and adsorption effect of modified filter rods on typical components (CO, H2O, benzene, and formaldehyde) in cigarette smoke. The surface structure and composition of the cellulose acetate filter rods were modified by changing the plasma treatment time. The modified filter rods were characterized by N2 physical adsorption (BET), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), contact angle of H2O, Fourier transform infrared spectroscopy (FTIR) and in situ DRIFTS. Various functional groups were found on the surface of filter rods with the introduction of plasma modification, which exhibited strong retention performance for water vapor in cigarette smoke at room temperature and significantly enhanced adsorption for harmful substances (CO, benzene, and formaldehyde) in cigarette smoke.

17.
Science ; 383(6680): 312-319, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38236974

RESUMO

Generating space-filling arrangements of most discrete polyhedra nanostructures of the same shape is not possible. However, if the appropriate individual building blocks are selected (e.g., cubes), or multiple shapes of the appropriate dimensions are matched (e.g., octahedra and tetrahedra) and their pairing interactions are subsequently forced, space-filled architectures may be possible. With flexible molecular ligands (polyethylene glycol-modified DNA), the shape of a polyhedral nanoparticle can be deliberately altered and used to realize geometries that favor space tessellation. In this work, 10 new colloidal crystals were synthesized from DNA-modified nanocrystal building blocks that differed in shapes and sizes, designed to form space-filling architectures with micron-scale dimensions. The insights and capabilities provided by this new strategy substantially expand the scope of colloidal crystals possible and provide an expanded tool kit for researchers interested in designing metamaterials.

18.
Basic Res Cardiol ; 119(1): 75-91, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38172251

RESUMO

Mast cells (MCs) are important intermediates between the nervous and immune systems. The cardiac autonomic nervous system (CANS) crucially modulates cardiac electrophysiology and arrhythmogenesis, but whether and how MC-CANS neuroimmune interaction influences arrhythmia remain unclear. Our clinical data showed a close relationship between serum levels of MC markers and CANS activity, and then we use mast cell stabilizers (MCSs) to alter this MC-CANS communication. MCSs, which are well-known anti-allergic agents, could reduce the risk of ventricular arrhythmia (VA) after myocardial infarction (MI). RNA-sequencing (RNA-seq) analysis to investigate the underlying mechanism by which MCSs could affect the left stellate ganglion (LSG), a key therapeutic target for modulating CANS, showed that the IL-6 and γ-aminobutyric acid (GABA)-ergic system may be involved in this process. Our findings demonstrated that MCSs reduce VA risk along with revealing the potential underlying antiarrhythmic mechanisms.


Assuntos
Antialérgicos , Estabilizadores de Mastócitos , Humanos , Neuroimunomodulação , Arritmias Cardíacas/prevenção & controle , Coração
19.
Nature ; 627(8005): 754-758, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38093004

RESUMO

Shock-breakout emission is light that arises when a shockwave, generated by the core-collapse explosion of a massive star, passes through its outer envelope. Hitherto, the earliest detection of such a signal was at several hours after the explosion1, although a few others had been reported2-7. The temporal evolution of early light curves should provide insights into the shock propagation, including explosion asymmetry and environment in the vicinity, but this has been hampered by the lack of multiwavelength observations. Here we report the instant multiband observations of a type II supernova (SN 2023ixf) in the galaxy M101 (at a distance of 6.85 ± 0.15 Mpc; ref. 8), beginning at about 1.4 h after the explosion. The exploding star was a red supergiant with a radius of about 440 solar radii. The light curves evolved rapidly, on timescales of 1-2 h, and appeared unusually fainter and redder than predicted by the models9-11 within the first few hours, which we attribute to an optically thick dust shell before it was disrupted by the shockwave. We infer that the breakout and perhaps the distribution of the surrounding dust were not spherically symmetric.

20.
Nat Mater ; 23(3): 424-428, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37919350

RESUMO

In principle, designing and synthesizing almost any class of colloidal crystal is possible. Nonetheless, the deliberate and rational formation of colloidal quasicrystals has been difficult to achieve. Here we describe the assembly of colloidal quasicrystals by exploiting the geometry of nanoscale decahedra and the programmable bonding characteristics of DNA immobilized on their facets. This process is enthalpy-driven, works over a range of particle sizes and DNA lengths, and is made possible by the energetic preference of the system to maximize DNA duplex formation and favour facet alignment, generating local five- and six-coordinated motifs. This class of axial structures is defined by a square-triangle tiling with rhombus defects and successive on-average quasiperiodic layers exhibiting stacking disorder which provides the entropy necessary for thermodynamic stability. Taken together, these results establish an engineering milestone in the deliberate design of programmable matter.


Assuntos
DNA , DNA/genética , DNA/química , Termodinâmica
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