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1.
Small ; : e2401706, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602199

RESUMO

In frigid regions, it is imperative to possess functionality materials that are ultrastrong, reusable, and economical, providing self-generated heat and electricity. One promising solution is a solar‒thermal‒electric (STE) generator, composed of solar‒thermal conversion phase change composites (PCCs) and temperature-difference power-generation-sheets. However, the existing PCCs face challenges with conflicting requirements for solar‒thermal conversion efficiency and mechanical robustness, mainly due to monotonous functionalized aerogel framework. Herein, a novel starch vitrimer aerogel is proposed that incorporates orientational distributed carboxylated carbon nanotubes (CCNT) to create PCC. This innovative design integrates large through-holes, mechanical robustness, and superior solar‒thermal conversion. Remarkably, PCC with only 0.8 wt.% CCNT loading achieves 85.8 MPa compressive strength, 102.4 °C at 200 mW cm-2 irradiation with an impressive 92.9% solar-thermal conversion efficiency. Noteworthy, the STE generator assembled with PCC harvests 99.1 W m-2 output power density, surpassing other reported STE generators. Strikingly, even under harsh conditions of -10 °C and 10 mW cm‒2 irradiation, the STE generator maintains 20 °C for PCC with 325 mV output voltage and 45 mA current, showcasing enhanced electricity generation in colder environments. This study introduces a groundbreaking STE generator, paving the way for self-sufficient heat and electricity supply in cold regions.

2.
Semin Ophthalmol ; : 1-7, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629866

RESUMO

BACKGROUND: Bioadhesion is the ability of materials to adhere to biological surfaces. Bioadhesives are substances which induce or promote bioadhesion. The internal application of bioadhesives is gaining popularity in recent years and is being increasingly utilized in vitreoretinal surgeries. The aim of this review is to discuss the various bioadhesives and their applications in vitreoretinal surgeries. METHODS: PubMed, Google Scholar, ePub and Cochrane library database were used for literature selection. Keywords such as vitreoretinal surgery, bioadhesives, intraocular bioadhesives, glue, fibrin glue, cyanoacrylate glue and transforming growth factor were used individually and in differing combinations to perform a comprehensive systematic literature search. RESULTS: A total of 47 papers were retrieved and included in this review. Cyanoacrylate glue was the first bioadhesive to be utilized for vitreoretinal surgery in human eyes in 1976. The most common indications for the use of bioadhesives were in optic disc pit maculopathy, macular holes and rhegmatogenous retinal detachments. CONCLUSION: The use of intraocular bioadhesives in vitreoretinal surgery represents a significant and evolving area of interest within ophthalmic research. While the pioneering use of cyanoacrylate glue, fibrin glue and transforming growth factor beta demonstrated the possible use of intraocular adhesives, fibrin glue is the most widely used intraocular bioadhesive in vitreoretinal surgery.

3.
Proc Natl Acad Sci U S A ; 121(15): e2321668121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557180

RESUMO

The ultimate regularity of quantum mechanics creates a tension with the assumption of classical chaos used in many of our pictures of chemical reaction dynamics. Out-of-time-order correlators (OTOCs) provide a quantum analog to the Lyapunov exponents that characterize classical chaotic motion. Maldacena, Shenker, and Stanford have suggested a fundamental quantum bound for the rate of information scrambling, which resembles a limit suggested by Herzfeld for chemical reaction rates. Here, we use OTOCs to study model reactions based on a double-well reaction coordinate coupled to anharmonic oscillators or to a continuum oscillator bath. Upon cooling, as one enters the tunneling regime where the reaction rate does not strongly depend on temperature, the quantum Lyapunov exponent can approach the scrambling bound and the effective reaction rate obtained from a population correlation function can approach the Herzfeld limit on reaction rates: Tunneling increases scrambling by expanding the state space available to the system. The coupling of a dissipative continuum bath to the reaction coordinate reduces the scrambling rate obtained from the early-time OTOC, thus making the scrambling bound harder to reach, in the same way that friction is known to lower the temperature at which thermally activated barrier crossing goes over to the low-temperature activationless tunneling regime. Thus, chemical reactions entering the tunneling regime can be information scramblers as powerful as the black holes to which the quantum Lyapunov exponent bound has usually been applied.

4.
Environ Res ; 252(Pt 2): 118963, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38640991

RESUMO

Cryoconite holes, small meltwater pools on the surface of glaciers and ice sheets, represent extremely cold ecosystems teeming with diverse microbial life. Cryoconite holes exhibit greater susceptibility to the impacts of climate change, underlining the imperative nature of investigating microbial communities as an essential module of polar and alpine ecosystem monitoring efforts. Microbes in cryoconite holes play a critical role in nutrient cycling and can produce bioactive compounds, holding promise for industrial and pharmaceutical innovation. Understanding microbial diversity in these delicate ecosystems is essential for effective conservation strategies. Therefore, this review discusses the microbial diversity in these extreme environments, aiming to unveil the complexity of their microbial communities. The current study envisages that cryoconite holes as distinctive ecosystems encompass a multitude of taxonomically diverse and functionally adaptable microorganisms that exhibit a rich microbial diversity and possess intricate ecological functions. By investigating microbial diversity and ecological functions of cryoconite holes, this study aims to contribute valuable insights into the broader field of environmental microbiology and enhance further understanding of these ecosystems. This review seeks to provide a holistic overview regarding the formation, evolution, characterization, and molecular adaptations of cryoconite holes. Furthermore, future research directions and challenges underlining the need for long-term monitoring, and ethical considerations in preserving these pristine environments are also provided. Addressing these challenges and resolutely pursuing future research directions promises to enrich our comprehension of microbial diversity within cryoconite holes, revealing the broader ecological and biogeochemical implications. The inferences derived from the present study will provide researchers, ecologists, and policymakers with a profound understanding of the significance and utility of cryoconite holes in unveiling the microbial diversity and its potential applications.

5.
Entropy (Basel) ; 26(3)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38539772

RESUMO

We study Einstein's gravity coupled to nonlinear electrodynamics with two parameters in anti-de Sitter spacetime. Magnetically charged black holes in an extended phase space are investigated. We obtain the mass and metric functions and the asymptotic and corrections to the Reissner-Nordström metric function when the cosmological constant vanishes. The first law of black hole thermodynamics in an extended phase space is formulated and the magnetic potential and the thermodynamic conjugate to the coupling are obtained. We prove the generalized Smarr relation. The heat capacity and the Gibbs free energy are computed and the phase transitions are studied. It is shown that the electric fields of charged objects at the origin and the electrostatic self-energy are finite within the nonlinear electrodynamics proposed.

6.
J Colloid Interface Sci ; 664: 838-847, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493649

RESUMO

Photoelectrochemical (PEC) water splitting has been widely investigated for solar-to-hydrogen conversion. However, issues like high charge recombination rate and slow surface water oxidation kinetics severely hinder its (PEC) conversion efficiency. Herein, we constructed MOF-derived CoOOH cocatalyst on BiVO4 photoanode, using a feasible electrochemical activation strategy. The BiVO4-based photoanode obtained shows a high photocurrent density of 3.15 mA/cm2 at 1.23 VRHE and low onset potential. Detailed experiments and theoretical calculations show that during the activation of CoZn-MOFs, there was a partial breakage of 2-methylimidazole (mIM) linker, an increase in the oxidation state of Cobalt ion (Co), and increased O2-. The high PEC performance is mainly attributed to the MOF-derived CoOOH, which provides rich active sites for hole extraction and reduces the overpotential for oxygen evolution reaction. Furthermore, when CoZnNiFe-LDHs were decorated on BiVO4 using the ions exchange method, the photocurrent density of BiVO4/CoZnNiFe-LDHs photoanode got to 4.0 mA/cm2 at 1.23 VRHE, accompanied with high stability. This study provides insights into understanding the key role played by the structural transformation of MOF cocatalyst in PEC water splitting processes.

7.
J Neurosci Methods ; 405: 110101, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38432305

RESUMO

BACKGROUND: In this study, we examined the utility of simultaneous scalp and stereotactic intracranial electroencephalography (SSIEEG) in epilepsy patients. Although SSIEEG offers valuable insights into epilepsy and cognitive function, its routine use is uncommon. Challenges include interpreting post-craniotomy scalp EEG due to surgically implanted electrodes. NEW METHOD: We describe our methodology for conducting SSIEEG recordings. To simulate the potential impact on EEG interpretation, we computed the leadfield of scalp electrodes with and without burrholes using Finite Element Analysis to compare the resulting sensitivity volume and waveforms of simulated intracranial signals between skulls with and without burrholes. RESULTS: The presence of burr holes in the skull layer of the leadfield models did not discernibly modify simulated waveforms or scalp EEG topology. Using realistic SEEG burr hole diameter, the difference in the average leadfield of scalp electrodes was 0.12% relative to the effect of switching two nearby electrodes, characterized by the cosine similarity difference. No patients experienced adverse events related to SSIEEG. COMPARISON WITH EXISTING METHODS: Although there is increasing acceptance and interest in SSIEEG, few studies have characterized the technical feasibility. Here, we demonstrate through modelling that scalp recordings from SSIEEG are comparable to that through an intact skull. CONCLUSION: The placement and simultaneous acquisition of scalp EEG during invasive monitoring through stereotactically inserted EEG electrodes is routinely performed at the Hospital for Sick Children. Scalp EEG recordings may assist with clinical interpretation. Burr holes in the skull layer did not discernibly alter EEG waveforms or topology.


Assuntos
Epilepsia , Couro Cabeludo , Criança , Humanos , Análise de Elementos Finitos , Eletroencefalografia/métodos , Eletrocorticografia/métodos , Epilepsia/diagnóstico , Epilepsia/cirurgia
8.
Mult Scler Relat Disord ; 84: 105494, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38359694

RESUMO

BACKGROUND AND OBJECTIVES: Diffusion basis spectrum imaging (DBSI) extracts multiple anisotropic and isotropic diffusion tensors, providing greater histopathologic specificity than diffusion tensor imaging (DTI). Persistent black holes (PBH) represent areas of severe tissue damage in multiple sclerosis (MS), and a high PBH burden is associated with worse MS disability. This study evaluated the ability of DBSI and DTI to predict which acute contrast-enhancing lesions (CELs) would persist as T1 hypointensities (i.e. PBHs) 12 months later. We expected that a higher radial diffusivity (RD), representing demyelination, and higher DBSI-derived isotropic non-restricted fraction, representing edema and increased extracellular space, of the acute CEL would increase the likelihood of future PBH development. METHODS: In this prospective cohort study, relapsing MS patients with ≥1 CEL(s) underwent monthly MRI scans for 4 to 6 months until gadolinium resolution. DBSI and DTI metrics were quantified when the CEL was most conspicuous during the monthly scans. To determine whether the CEL became a PBH, a follow-up MRI was performed at least 12 months after the final monthly scan. RESULTS: The cohort included 20 MS participants (median age 33 years; 13 women) with 164 CELs. Of these, 59 (36 %) CELs evolved into PBHs. At Gd-max, DTI RD and AD of all CELs increased, and both metrics were significantly elevated for CELs which became PBHs, as compared to non-black holes (NBHs). DTI RD above 0.74 conferred an odds ratio (OR) of 7.76 (CI 3.77-15.98) for a CEL becoming a PBH (AUC 0.80, CI 0.73-0.87); DTI axial diffusivity (AD) above 1.22 conferred an OR of 7.32 (CI 3.38-15.86) for becoming a PBH (AUC 0.75, CI 0.66-0.83). DBSI RD and AD did not predict PBH development in a multivariable model. At Gd-max, DBSI restricted fraction decreased and DBSI non-restricted fraction increased in all CELs, and both metrics were significantly different for CELs which became PBHs, as compared to NBHs. A CEL with a DBSI non-restricted fraction above 0.45 had an OR of 4.77 (CI 2.35-9.66) for becoming a PBH (AUC 0.74, CI 0.66-0.81); a CEL with a DBSI restricted fraction below 0.07 had an OR of 9.58 (CI 4.59-20.02) for becoming a PBH (AUC 0.80, 0.72-0.87). CONCLUSION: Our findings suggest that greater degree of edema/extracellular space in a CEL is a predictor of tissue destruction, as evidenced by PBH evolution.


Assuntos
Esclerose Múltipla , Humanos , Feminino , Adulto , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Imagem de Tensor de Difusão/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Estudos Prospectivos , Edema/patologia
9.
Q J Exp Psychol (Hove) ; : 17470218241232665, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38311605

RESUMO

Trypophobia is the condition in which individuals report a range of negative emotions when viewing clusters of small holes. Since the phenomenon was first described in the peer-reviewed literature a decade ago, 49 papers have appeared together with hundreds of news articles. There has also been much discussion on various Internet forums, including medical and health-related websites. In the present article, we examine the degree to which the phenomenon is caused by a form of social learning, specifically, its ubiquitous social media presence. We also examined its prevalence among the broad population. In Experiment 1 (n = 2,558), we assessed whether younger people and females (i.e., greater social media users) are more sensitive to trypophobic stimuli, as predicted by the social media hypothesis. In Experiment 2 (n = 283), we examined whether sensitivity to trypophobic stimuli and rates of trypophobia is greater in people who are aware of the condition's existence, as opposed to those who have never heard of the phenomenon. In line with the social media theory, results showed that younger people and females are indeed more susceptible to trypophobia. However, 24% of trypophobic individuals have never heard of the condition. Overall, these data suggest that both social learning and non-social learning contribute to trypophobia. We also find that the prevalence of trypophobia is approximately 10%.

10.
Cureus ; 16(1): e51892, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38333474

RESUMO

Hay-holes are a design feature in many traditionally built barns that serve as a portal through which stored hay is passed to the lower level where animals are fed. Unfortunately, children sometimes fall through the hay-hole to the concrete or packed earth below. Available data on the frequency and types of hay-hole injuries is limited. The purpose of this study was to better characterize the resultant injuries and identify prognostic factors that predict outcomes from them. We performed a retrospective review of 53 children admitted to the Penn State Hershey Children's Hospital at the Penn State Hershey Medical Center with injuries due to a fall through a hay-hole over 15 years. Compared to urban trauma, hay-hole falls more frequently involve younger children and craniofacial injuries. Although they may result in significant injuries, they are rarely fatal. Greater fall height is associated with longer length of stay (LOS) but not with a greater frequency of intubation, intracranial hemorrhage, or skull fracture. A re-examination of barn design may help to reduce the frequency of this injury type.

11.
Sensors (Basel) ; 24(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38339533

RESUMO

The two-dimensional (2D) cross-hole seismic computed tomography (CT) imaging acquisition method has the potential to characterize the target zone optimally compared to surface seismic surveys. It has wide applications in oil and gas exploration, engineering geology, etc. Limited to 2D hole velocity profiling, this method cannot acquire three-dimensional (3D) information on lateral geological structures outside the profile. Additionally, the sensor data received by cross-hole seismic exploration constitute responses from geological bodies in 3D space and are potentially affected by objects outside the well profiles, distorting the imaging results and geological interpretation. This paper proposes a 3D cross-hole acoustic wave reverse-time migration imaging method to capture 3D cross-hole geological structures using sensor settings in multi-cross-hole seismic research. Based on the analysis of resulting 3D cross-hole images under varying sensor settings, optimizing the observation system can aid in the cost-efficient obtainment of the 3D underground structure distribution. To verify this method's effectiveness on 3D cross-hole structure imaging, numerical simulations were conducted on four typical geological models regarding layers, local high-velocity zones, large dip angles, and faults. The results verify the model's superiority in providing more reliable and accurate 3D geological information for cross-hole seismic exploration, presenting a theoretical basis for processing and interpreting cross-hole data.

12.
Neuroradiology ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374410

RESUMO

OBJECTIVES: In the neuroradiological work-up of Multiple Sclerosis (MS), the detection of "black holes" (BH) represent an information of undeniable importance. Nevertheless, different sequences can be used in clinical practice to evaluate BH in MS. Aim of this study was to investigate the possible impact of different sequences, resolutions, and levels of expertise on the intra- and inter-rater reliability identification of BH in MS. METHODS: Brain MRI scans of 85 MS patients (M/F = 22/63; mean age = 36.0 ± 10.2 years) were evaluated in this prospective single-center study. The acquisition protocol included a 3 mm SE-T1w sequence, a 1 mm 3D-GrE-T1w sequence from which a resliced 3 mm sequence was also obtained. Images were evaluated independently by two readers of different expertise at baseline and after a wash-out period of 30 days. The intraclass correlation coefficient (ICC) was calculated as an index of intra and inter-reader reliability. RESULTS: For both readers, the intra-reader ICC analysis showed that the 3 mm SE-T1w and 3 mm resliced GrE-T1w images achieved an excellent performance (both with an ICC ≥ 0.95), while 1 mm 3D-GrE-T1w scans achieved a moderate one (ICC < 0.90). The inter-reader analysis showed that each of the three sequences achieved a moderate performance (all ICCs < 0.90). CONCLUSIONS: The 1 mm 3D-GrE-T1w sequence seems to be prone to a greater intra-reader variability compared to the 3 mm SE-T1w, with this effect being driven by the higher spatial resolution of the first sequence. To ensure reliability levels comparable with the standard SE-T1w in BH count, an assessment on a 3 mm resliced GrE-T1w sequence should be recommended.

13.
ACS Appl Mater Interfaces ; 16(5): 6068-6077, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38258520

RESUMO

Deep-level defects in ß-Ga2O3 that worsen the response speed and dark current (Id) of photodetectors (PDs) have been a long-standing issue for its application. Herein, an in situ grown single-crystal Ga2O3 nanoparticle seed layer (NPSL) was used to shorten the response time and reduce the Id of metal-semiconductor-metal (MSM) PDs. With the NPSL, the Id was reduced by 4 magnitudes from 0.389 µA to 81.03 pA, and the decay time (τd1/τd2) decreased from 258/1690 to 62/142 µs at -5 V. In addition, the PDs with the NPSL also exhibit a high responsivity (43.5 A W-1), high specific detectivity (2.81 × 1014 Jones), and large linear dynamic range (61 dB) under 254 nm illumination. The mechanism behind the performance improvement can be attributed to the suppression of the deep-level defects (i.e., self-trapped holes) and increase of the Schottky barrier. The barrier height extracted is increased by 0.18 eV compared with the case without the NPSL. Our work contributes to understanding the relationship between defects and the performance of PDs based on heteroepitaxial ß-Ga2O3 thin films and provides an important reference for the development of high-speed and ultrasensitive deep ultraviolet PDs.

14.
Materials (Basel) ; 17(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38204106

RESUMO

In a classic paper of 1960, W. H. Cherry and J. I. Gittleman discussed various thermal and electrodynamic aspects of the superconductive transition process relevant to practical applications. In a section of the paper that has remained unnoticed, they proposed a physical model for the Meissner effect. Earlier in 1940-1943, in work that has also remained unnoticed, K. M. Koch had introduced related physical ideas to explain the Meissner effect. Still earlier in 1937, J. C. Slater proposed a model to explain the perfect diamagnetism of superconductors. None of these ideas are part of the conventional London-BCS understanding of superconductivity, yet I will argue that they are essential to understand the Meissner effect, the most fundamental property of superconductors. The unconventional theory of hole superconductivity unifies and extends these ideas. A key missing element in the conventional theory as well as in these early theories is electron-hole asymmetry. A proper understanding of the Meissner effect may help with practical applications of superconductors, as well as to find new superconducting materials with desirable properties.

15.
Heliyon ; 10(1): e23920, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38234921

RESUMO

Structural components are generally composed of material discontinuities, including open holes, which are considered stress concentrators in engineering components. In view of this, assessing the influence of open holes on the tensile properties is crucial to determine the sensitivity and tensile strength of a particular material. Nevertheless, investigation of the impact of open holes on the tensile properties of SS400 steel sheets is very limited and yet to be explored. Therefore, this study was performed to optimize the effects of open holes on the tensile properties of SS400 sheet specimens based on a Full Factorial Design (FFD) experiment. Four input parameters that represent various hole configurations, which include the hole diameter, location of the hole, number of holes, and hole shape, were considered in this study to develop the experimental-based prediction models to optimize the output performance, namely yield strength, ultimate tensile strength, and ultimate elongation, commonly denoted as YS, UTS, and UE respectively. A total of 10 additional experimental trials were then utilized to verify the constructed models. In addition, the weight fractions for YS, UTS, and UE were identified using the Criteria Importance Through Inter-Criteria Correlation (CRITIC) method. Subsequently, the Desirability Function Analysis (DFA) is utilized to pinpoint the optimal parameter conditions for maximizing the tensile properties. Based on the results, all four parameters showed significant effects on the response variables, except the number of holes for UTS and hole location for UE. The diameter also recorded the highest contribution toward UTS and UE, followed by the hole shape. Regarding YS, hole diameter takes precedence, with the number of holes as the second most influential factor. Furthermore, the average absolute percent deviation for the prediction responses of 10 experimental cases were 1.06 %, 0.90 %, and 0.85 % for YS, UTS, and UE, respectively, confirming the validity of the constructed models. Meanwhile, the CRITIC method estimated the weight fractions for YS, UTS and UE from the experimental data, which were 0.3825, 0.2559, and 0.3616, respectively. The DFA-derived composite desirability, rated at 0.9820, suggests optimal conditions: a 1 mm hole diameter, centered hole location, three holes, and a hexagonal shape. The minimal deviations between predicted and experimental values affirm the robustness of the models. Overall, this investigation yields important insights for optimizing open holes and elevating the tensile performance of SS400 sheet specimens.

16.
Philos Trans A Math Phys Eng Sci ; 382(2267): 20230035, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38219780

RESUMO

This paper is about two important trends of scattering theory in general relativity: time-dependent spectral analytic scattering and conformal scattering. The former was initiated by Jonathan Dimock and Bernard Kay in the mid-1980s and is based on spectral and functional analysis. The latter was proposed by Roger Penrose in 1965 and then constructed for the first time by Gerard Friedlander in 1980 by putting together Penrose's conformal method and another analytic approach to scattering: the Lax-Phillips theory due to Peter Lax and Ralph Phillips. We shall review the history of the two approaches and explain their general principles. We shall also explore an important question: 'can the tools of one approach be used to obtain a complete construction in the other?' This article is part of a discussion meeting issue 'At the interface of asymptotics, conformal methods and analysis in general relativity'.

17.
Philos Trans A Math Phys Eng Sci ; 382(2267): 20230046, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38219779

RESUMO

This work offers a didactical introduction to the calculations and geometrical properties of a static, spherically symmetric spacetime foliated by hyperboloidal time surfaces. We discuss the various degrees of freedom involved, namely the height function, responsible for introducing the hyperboloidal time coordinate, and a radial compactification function. A central outcome is the expression of the Trautman-Bondi mass in terms of the hyperboloidal metric functions. Moreover, we apply this formalism to a class of wave equations commonly used in black-hole perturbation theory. Additionally, we provide a comprehensive derivation of the hyperboloidal minimal gauge, introducing two alternative approaches within this conceptual framework: the in-out and out-in strategies. Specifically, we demonstrate that the height function in the in-out strategy follows from the well-known tortoise coordinate by changing the sign of the terms that become singular at future null infinity. Similarly, for the out-in strategy, a sign change also occurs in the tortoise coordinate's regular terms. We apply the methodology to the following spacetimes: Singularity-approaching slices in Schwarzschild, higher-dimensional black holes, black hole with matter halo, and Reissner-Nordström-de Sitter. From this heuristic study, we conjecture that the out-in strategy is best adapted for black hole geometries that account for environmental or effective quantum effects. This article is part of a discussion meeting issue 'At the interface of asymptotics, conformal methods and analysis in general relativity'.

18.
Molecules ; 29(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38257378

RESUMO

The high electrons and holes recombination rate of ZnIn2S4 significantly limits its photocatalytic performance. Herein, a simple in situ photodeposition strategy is adopted to introduce the cocatalyst cobalt phosphate (Co-Pi) on ZnIn2S4, aiming at facilitating the separation of electron-hole by promoting the transfer of photogenerated holes of ZnIn2S4. The study reveals that the composite catalyst has superior photocatalytic performance than blank ZnIn2S4. In particular, ZnIn2S4 loaded with 5% Co-Pi (ZnIn2S4/5%Co-Pi) has the best photocatalytic activity, and the H2 production rate reaches 3593 µmol·g-1·h-1, approximately double that of ZnIn2S4 alone. Subsequent characterization data demonstrate that the introduction of the cocatalyst Co-Pi facilitates the transfer of ZnIn2S4 holes, thus improving the efficiency of photogenerated carrier separation. This investigation focuses on the rational utilization of high-content and rich cocatalysts on earth to design low-cost and efficient composite catalysts to achieve sustainable photocatalytic hydrogen evolution.

19.
Eur J Ophthalmol ; 34(1): 304-309, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37820366

RESUMO

PURPOSE: To describe a new surgical technique involving the use of a human amniotic membrane (hAM) epiretinal patch to treat a primary macular hole retinal detachment (MHRD) in a highly myopic patient. METHODS: A 60 years old highly myopic man was referred to our clinic with a diagnosis of MHRD in his right eye. The patient was pseudophakic, with a visual acuity of counting fingers at the baseline evaluation. Pars plana vitrectomy was performed, a small retinotomy was created at the inner margin of the staphyloma, and membrane blue dual was used to obtain an adequate peeling of the inner limiting membrane. Then, a 1.5 mm diameter circular hAM patch was obtained and positioned over the macular hole with the chorion layer settled over the retina. After a complete fluid-air exchange, 20% sulfur hexafluoride gas was used as endotamponade, and the patient was asked to remain face down for three days. RESULTS: Four weeks after surgery, optical coherence tomography (OCT) scan showed the hAM patch, visualized as a distinct hyperreflective layer well integrated with the retina. Nine months after surgery, the macular hole was closed, the retina reattached, the hAM patch was adherent to the retina, and the patient presented a best-corrected visual acuity improved to 0.7 logMar. No postoperative adverse events were registered during the follow-up. CONCLUSIONS: Epiretinal hAM implant could represent a novel surgical technique, feasible and easier compared to other current techniques used to treat MHRD in highly myopic patients.


Assuntos
Membrana Epirretiniana , Miopia , Descolamento Retiniano , Perfurações Retinianas , Masculino , Humanos , Pessoa de Meia-Idade , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/etiologia , Descolamento Retiniano/cirurgia , Perfurações Retinianas/diagnóstico , Perfurações Retinianas/etiologia , Perfurações Retinianas/cirurgia , Âmnio , Estudos Retrospectivos , Miopia/cirurgia , Tomografia de Coerência Óptica , Membrana Epirretiniana/complicações , Membrana Epirretiniana/cirurgia , Vitrectomia/métodos
20.
mBio ; 15(2): e0129023, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38126784

RESUMO

The infection cycle of phage λ terminates in lysis mediated by three types of lysis proteins, each disrupting a layer in the bacterial envelope: the S105 holin, the R endolysin, and the Rz/Rz1 spanin complex targeting the inner membrane, cell wall or peptidoglycan, and the outer membrane, respectively. Video microscopy has shown that in most infections, lysis occurs as a sudden, explosive event at a cell pole, such that the initial product is a less refractile ghost that retains rod-shaped morphology. Here, we investigate the molecular basis of polar lysis using time-lapse fluorescence microscopy. The results indicate that the holin determines the morphology of lysis by suddenly forming two-dimensional rafts at the poles about 100 s prior to lysis. Given the physiological and biochemical similarities between the lambda holin and other class I holins, dynamic redistribution and sudden concentration may be common features of holins, probably reflecting the fitness advantage of all-or-nothing lysis regulation.IMPORTANCEIn this study, we use fluorescent video microscopy to track -green fluorescent protein (GFP)-labeled holin in the minutes prior to phage lysis. Our work contextualizes prior genetic and biochemical data, showing when hole formation starts and where holin oligomers form in relation to the site of lytic rupture. Furthermore, prior work showed that the morphology of lambda-infected cells is characterized by an explosive event starting at the cell pole; however, the basis for this was not clear. This study shows that holin most often oligomerizes at cell poles and that the site of the oligomerization is spatially correlated with the site of lytic blowout. Therefore, the holin is the key contributor to polar lysis morphology for phage lambda.


Assuntos
Bacteriófago lambda , Proteínas Virais , Proteínas Virais/metabolismo , Bacteriófago lambda/genética , Morte Celular , Parede Celular/metabolismo , Bacteriólise
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