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1.
Proc Natl Acad Sci U S A ; 120(38): e2306601120, 2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37695899

ABSTRACT

Cherenkov radiation occurs only when a charged particle moves with a velocity exceeding the phase velocity of light in that matter. This radiation mechanism creates directional light emission at a wide range of frequencies and could facilitate the development of on-chip light sources except for the hard-to-satisfy requirement for high-energy particles. Creating Cherenkov radiation from low-energy electrons that has no momentum mismatch with light in free space is still a long-standing challenge. Here, we report a mechanism to overcome this challenge by exploiting a combined effect of interfacial Cherenkov radiation and umklapp scattering, namely the constructive interference of light emission from sequential particle-interface interactions with specially designed (umklapp) momentum-shifts. We find that this combined effect is able to create the interfacial Cherenkov radiation from ultralow-energy electrons, with kinetic energies down to the electron-volt scale. Due to the umklapp scattering for the excited high-momentum Bloch modes, the resulting interfacial Cherenkov radiation is uniquely featured with spatially separated apexes for its wave cone and group cone.

2.
FASEB J ; 38(15): e23850, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39091212

ABSTRACT

Atherosclerosis is a leading cause of cardiovascular diseases (CVDs), often resulting in major adverse cardiovascular events (MACEs), such as myocardial infarction and stroke due to the rupture or erosion of vulnerable plaques. Ferroptosis, an iron-dependent form of cell death, has been implicated in the development of atherosclerosis. Despite its involvement in CVDs, the specific role of ferroptosis in atherosclerotic plaque stability remains unclear. In this study, we confirmed the presence of ferroptosis in unstable atherosclerotic plaques and demonstrated that the ferroptosis inhibitor ferrostatin-1 (Fer-1) stabilizes atherosclerotic plaques in apolipoprotein E knockout (Apoe-/-) mice. Using bioinformatic analysis combining RNA sequencing (RNA-seq) with single-cell RNA sequencing (scRNA-seq), we identified Yes-associated protein 1 (YAP1) as a potential key regulator of ferroptosis in vascular smooth muscle cells (VSMCs) of unstable plaques. In vitro, we found that YAP1 protects against oxidized low-density lipoprotein (oxLDL)-induced ferroptosis in VSMCs. Mechanistically, YAP1 exerts its anti-ferroptosis effects by regulating the expression of glutaminase 1 (GLS1) to promote the synthesis of glutamate (Glu) and glutathione (GSH). These findings establish a novel mechanism where the inhibition of ferroptosis promotes the stabilization of atherosclerotic plaques through the YAP1/GLS1 axis, attenuating VSMC ferroptosis. Thus, targeting the YAP1/GLS1 axis to suppress VSMC ferroptosis may represent a novel strategy for preventing and treating unstable atherosclerotic plaques.


Subject(s)
Ferroptosis , Muscle, Smooth, Vascular , Plaque, Atherosclerotic , YAP-Signaling Proteins , Animals , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/pathology , Mice , Plaque, Atherosclerotic/metabolism , Plaque, Atherosclerotic/pathology , YAP-Signaling Proteins/metabolism , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Humans , Male , Mice, Inbred C57BL , Atherosclerosis/metabolism , Atherosclerosis/pathology , Atherosclerosis/genetics , Mice, Knockout , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Phenylenediamines/pharmacology , Cyclohexylamines/pharmacology , Apolipoproteins E/metabolism , Apolipoproteins E/genetics
3.
Clin Immunol ; 259: 109879, 2024 02.
Article in English | MEDLINE | ID: mdl-38142901

ABSTRACT

The impact of Omicron infections on the clinical outcome and immune responses of myasthenia gravis (MG) remained largely unknown. From a prospective multicenter MG cohort (n = 189) with 197 myasthenic crisis (MC), we finally included 41 independent MG patients to classify into two groups: the Omicron Group (n = 13) and the Control Group (n = 28). In this matched cohort study, all-cause mortality was 7.69% (1/13) in Omicron Group and 14.29% (4/28) in Control Group. A higher proportion of elevated serum IL-6 was identified in the Omicron Group (88.89% vs 52.38%, P = 0.049). In addition, the proportions of CD3+CD8+T in lymphocytes and Tregs in CD3+CD4+ T cells were significantly elevated in the Omicron Group (both P = 0.0101). After treatment, the Omicron Group exhibited a marked improvement in MG-ADL score (P = 0.026) and MG-QoL-15 (P = 0.0357). MCs with Omicron infections were associated with elevated serum IL-6 and CD3+CD8+T response. These patients tended to present a better therapeutic response after fast-acting therapies and anti-IL-6 treatment.


Subject(s)
Interleukin-6 , Myasthenia Gravis , Humans , Prospective Studies , Cohort Studies , Quality of Life , Myasthenia Gravis/drug therapy
4.
Small ; : e2404143, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39344520

ABSTRACT

Peroxydisulfate (PDS), a popular molecule that is able to oxidize organic compounds, is garnering attention across various disciplines of chemistry, materials, pharmaceuticals, environmental remediation, and sustainability. Methylene blue (MB) is a model pollutant that can be readily oxidized by PDS-derived radicals. Unlike the conventional degradation process, here a reversible "dissolution-precipitation" phenomenon is discovered, triggered by a simple mixing of PDS and MB, revealing a novel application of PDS in fabricating self-assembled ultra-long nanowires with MB. This phenomenon is unique to PDS and MB, different from the traditional salting out or self-aggregation of dyes. Formation of nanowires facilitated by electrostatic interaction between S+ and O- moieties and π-π stacking is reversible, controlled by temperature and the solvent polarity. MB1-PDS-MB2 configuration (MB: PDS = 2:1) is theoretically predicted by density functional theory (DFT) calculations and further validated by stoichiometric ratios of carbon, sulfur, and nitrogen in the obtained precipitates (MBO). This untapped feature of PDS enables the development of colorimetric quantitative detection of PDS and sustainable dye recycling. Far more than those demonstrated cases, the potentialities of MBO as a nanomaterial merit further exploration.

5.
Opt Lett ; 49(4): 826-829, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38359192

ABSTRACT

Directionally molding the near-field and far-field radiation lies at the heart of nanophotonics and is crucial for applications such as on-chip information processing and chiral quantum networks. The most fundamental model for radiating structures is a dipolar source located inside homogeneous matter. However, the influence of matter on the directionality of dipolar radiation is oftentimes overlooked, especially for the near-field radiation. As background, the dipole-matter interaction is intrinsically asymmetric and does not fulfill the duality principle, originating from the inherent asymmetry of Maxwell's equations, i.e., electric charge and current density are ubiquitous but their magnetic counterparts are non-existent to elusive. We find that the asymmetric dipole-matter interaction could offer an enticing route to reshape the directionality of not only the near-field radiation but also the far-field radiation. As an example, both the near-field and far-field radiation directionality of the Huygens dipole (located close to a dielectric-metal interface) would be reversed if the dipolar position is changed from the dielectric region to the metal region.

6.
Opt Lett ; 49(13): 3737-3740, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38950255

ABSTRACT

An approach for continuous tuning of on-chip optical delay with a microring resonator is proposed and demonstrated. By introducing an electro-optically tunable waveguide coupler, the bus waveguide to the resonance coupling can be effectively tuned from the under-coupling regime to the over-coupling regime. The optical delay is experimentally characterized by measuring the relative phase shift between lasers and shows a large dynamic range of delay from -600 to 600 ps and an efficient tuning of delay from -430 to -180 ps and from 40 to 240 ps by only a 5 V voltage.

7.
Phys Rev Lett ; 132(3): 036502, 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38307085

ABSTRACT

The recently discovered nickelate superconductor La_{3}Ni_{2}O_{7} has a high transition temperature near 80 K under pressure, providing an additional avenue for exploring unconventional superconductivity. Here, with state-of-the-art tensor-network methods, we study a bilayer t-J-J_{⊥} model for La_{3}Ni_{2}O_{7} and find a robust s-wave superconductive (SC) order mediated by interlayer magnetic couplings. Large-scale density matrix renormalization group calculations find algebraic pairing correlations with Luttinger parameter K_{SC}≲1. Infinite projected entangled-pair state method obtains a nonzero SC order directly in the thermodynamic limit, and estimates a strong pairing strength Δ[over ¯]_{z}∼O(0.1). Tangent-space tensor renormalization group simulations elucidate the temperature evolution of SC pairing and further determine a high SC temperature T_{c}^{*}/J∼O(0.1). Because of the intriguing orbital selective behaviors and strong Hund's rule coupling in the compound, t-J-J_{⊥} model has strong interlayer spin exchange (while negligible interlayer hopping), which greatly enhances the SC pairing in the bilayer system. Such a magnetically mediated pairing has also been observed recently in the optical lattice of ultracold atoms. Our accurate and comprehensive tensor-network calculations reveal a robust SC order in the bilayer t-J-J_{⊥} model and shed light on the pairing mechanism of the high-T_{c} nickelate superconductor.

8.
FASEB J ; 37(10): e23203, 2023 10.
Article in English | MEDLINE | ID: mdl-37732638

ABSTRACT

Exercise is widely recognized as beneficial for tendon healing. Recently, it has been described that muscle-derived molecules secreted in response to static exercise influence tendon healing. In this study, the optimal static loading intensity for tendon healing and the composition of secretome released by myoblasts in response to different intensities of static strain were investigated. In an in vitro coculture model, myoblasts were mechanically loaded using a Flexcell Tension System. Tenocytes were seeded on transwell inserts that allowed communication between the tenocytes and myoblasts without direct contact. Proliferation and migration assays, together with RNA sequencing, were used to determine potential cellular signaling pathways. The secretome from myoblasts exposed to 2% static loading increased the proliferation and migration of the cocultured tenocytes. RNA-seq analysis revealed that this loading condition upregulated the expression of numerous genes encoding secretory proteins, including insulin-like growth factor-1 (IGF-1). Confirmation of IGF-1 expression and secretion was carried out using qPCR and enzyme-linked immunosorbt assay (ELISA), revealing a statistically significant upregulation in response to 2% static loading in comparison to both control conditions and higher loading intensities of 5% and 10%. Addition of an inhibitor of the IGF-1 receptor (PQ401) to the tenocytes significantly reduced myoblast secretome-induced tenocyte proliferation. In conclusion, IGF-1 may be an important molecule in the statically loaded myoblast secretome, which is responsible for influencing tenocytes during exercise-induced healing.


Subject(s)
Insulin-Like Growth Factor I , Receptor, IGF Type 1 , Tenocytes , Secretome , Myoblasts , Cell Proliferation
9.
Environ Sci Technol ; 58(28): 12477-12487, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-38943037

ABSTRACT

Although the impacts of exotic wetland plant invasions on native biodiversity, landscape features, and carbon-nitrogen cycles are well appreciated, biogeochemical consequences posed by ecological competition, such as the heterogeneity of dissolved organic matter (DOM) from plant detritus and its impact on the formation of reactive oxygen species, are poorly understood. Thus, this study delves into O2•- photogeneration potential of DOM derived from three different parts (stem, leaf, and panicle) of invasive Spartina alterniflora (SA) and native Phragmites australis (PA). It is found that DOM from the leaves of SA and the panicles of PA has a superior ability to produce O2•-. With more stable aromatic structures and a higher proportion of sulfur-containing organic compounds, SA-derived DOM generally yields more O2•- than that derived from PA. UVA exposure enhances the leaching of diverse DOM molecules from plant detritus. Based on the reported monitoring data and our findings, the invasion of SA is estimated to approximately double the concentration of O2•- in the surrounding water bodies. This study can help to predict the underlying biogeochemical impacts from the perspective of aquatic photochemistry in future scenarios of plant invasion, seawater intrusion, wetland degradation, and elevated solar UV radiation.


Subject(s)
Wetlands , Superoxides/metabolism , Introduced Species , Plants/metabolism
10.
Article in English | MEDLINE | ID: mdl-39212724

ABSTRACT

This research aims to study the factors contributing to Long COVID and its effects on motor and cognitive brain regions using population surveys and brain imaging. The goal is to provide new insights into the neurological effects of the illness and establish a basis for addressing neuropsychiatric symptoms associated with Long COVID. Study 1 used a cross-sectional design to collect data on demographic characteristics and factors related to Long COVID symptoms in 551 participants. In Study 2, subjects with Long COVID and SARS-CoV-2 uninfected individuals underwent fNIRS monitoring while performing various tasks. Study 1 found that gender, age, BMI, Days since the first SARS-CoV-2 infection, and Symptoms at first onset influenced Long COVID performance. Study 2 demonstrated that individuals in the SARS-CoV-2 uninfected group exhibited greater activation of cognitive function-related brain regions than those in the Long COVID group while performing a level walking task. Furthermore, individuals in the Long COVID group without functional impairment displayed higher activation of brain regions associated with motor function during a weight-bearing walking task than those with functional impairment. Among individuals with Long COVID, those with mild symptoms at onset exhibited increased activation of brain regions linked to motor and cognitive function relative to those with moderate symptoms at onset. Individuals with Long COVID exhibited decreased activation in brain regions associated with cognitive and motor function compared to SARS-CoV-2 uninfected individuals. Moreover, those with more severe initial symptoms or functional impairment displayed heightened inhibition in these brain regions.

11.
Support Care Cancer ; 32(5): 314, 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38683417

ABSTRACT

PURPOSE: This study aimed to assess the different needs of patients with breast cancer and their families in online health communities at different treatment phases using a Latent Dirichlet Allocation (LDA) model. METHODS: Using Python, breast cancer-related posts were collected from two online health communities: patient-to-patient and patient-to-doctor. After data cleaning, eligible posts were categorized based on the treatment phase. Subsequently, an LDA model identifying the distinct need-related topics for each phase of treatment, including data preprocessing and LDA topic modeling, was established. Additionally, the demographic and interactive features of the posts were manually analyzed. RESULTS: We collected 84,043 posts, of which 9504 posts were included after data cleaning. Early diagnosis and rehabilitation treatment phases had the highest and lowest number of posts, respectively. LDA identified 11 topics: three in the initial diagnosis phase and two in each of the remaining treatment phases. The topics included disease outcomes, diagnosis analysis, treatment information, and emotional support in the initial diagnosis phase; surgical options and outcomes, postoperative care, and treatment planning in the perioperative treatment phase; treatment options and costs, side effects management, and disease prognosis assessment in the non-operative treatment phase; diagnosis and treatment options, disease prognosis, and emotional support in the relapse and metastasis treatment phase; and follow-up and recurrence concerns, physical symptoms, and lifestyle adjustments in the rehabilitation treatment phase. CONCLUSION: The needs of patients with breast cancer and their families differ across various phases of cancer therapy. Therefore, specific information or emotional assistance should be tailored to each phase of treatment based on the unique needs of patients and their families.


Subject(s)
Breast Neoplasms , Data Mining , Humans , Breast Neoplasms/psychology , Breast Neoplasms/therapy , Breast Neoplasms/rehabilitation , Female , Data Mining/methods , Needs Assessment , Internet
12.
Chaos ; 34(10)2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39361816

ABSTRACT

In this study, we propose a modified reaction-diffusion prey-predator model with a Holling-II function for binary data classification. In the model, we use u and v to represent the densities of prey and predators, respectively. We modify the original equation by substituting the term v with f-v to obtain a stable and clear nonlinear decision surface. By employing a finite difference method for numerical solution of the original model, we conduct various experiments in two-dimensional and three-dimensional spaces to validate the feasibility of the classifier. Additionally, with consideration for wide real applications, we perform classification experiments on electroencephalogram signals, demonstrating the effectiveness and robustness of the classifier in binary data classification.

13.
BMC Med Educ ; 24(1): 1045, 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39334303

ABSTRACT

INTRODUCTION: While the opioid crisis has been a significant concern in North America, Taiwan has not encountered a similar crisis. This study investigated medical students' perceptions of opioid therapy for chronic pain management in Taiwan. METHODS: A cross-sectional questionnaire survey was conducted among third- and fourth-year medical students who had completed an 18-hour pain medicine curriculum, in comparison with those who did not take the course in Mar 2022 and May 2023. The survey assessed their knowledge, attitude, and perceptions of the opioid crisis in the United States and Taiwan. RESULTS: In total, 135 (88.2%) of 153 senior medical students who had completed the curriculum responded to the survey. They exhibited a better understanding of opioids (P < 0.001) and held a more negative attitude toward opioid use (P = 0.011) compared with 105 students who did not take the course. Additionally, out of 240 respondents, 177 (73.8%) acknowledged the ongoing opioid crisis in the United States, while only 70 (29.2%) disagreed with the notion of an ongoing opioid crisis in Taiwan. Furthermore, 90% of all students expressed agreement with the need for further education on chronic pain management after graduation. CONCLUSION: Among senior medical students in Taiwan, those who completed an elective pain medicine curriculum demonstrated enhanced knowledge of opioids, a more cautious attitude toward opioid use, and a willingness to receive further education on chronic pain management. Over 70% of students remained uncertain or incorrectly believed that there was an opioid crisis in Taiwan.


Subject(s)
Analgesics, Opioid , Curriculum , Health Knowledge, Attitudes, Practice , Pain Management , Students, Medical , Humans , Cross-Sectional Studies , Taiwan , Students, Medical/psychology , Analgesics, Opioid/therapeutic use , Male , Female , Surveys and Questionnaires , Education, Medical, Undergraduate , Adult , Chronic Pain/drug therapy , Young Adult , Attitude of Health Personnel
14.
EMBO J ; 38(5)2019 03 01.
Article in English | MEDLINE | ID: mdl-30777856

ABSTRACT

The sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 2a (SERCA2a) performs active reuptake of cytoplasmic Ca2+ and is a major regulator of cardiac muscle contractility. Dysfunction or dysregulation of SERCA2a is associated with heart failure, while restoring its function is considered as a therapeutic strategy to restore cardiac performance. However, its structure has not yet been determined. Based on native, active protein purified from pig ventricular muscle, we present the first crystal structures of SERCA2a, determined in the CPA-stabilized E2-AlF4- form (3.3 Å) and the Ca2+-occluded [Ca2]E1-AMPPCP form (4.0 Å). The structures are similar to the skeletal muscle isoform SERCA1a pointing to a conserved mechanism. We seek to explain the kinetic differences between SERCA1a and SERCA2a. We find that several isoform-specific residues are acceptor sites for post-translational modifications. In addition, molecular dynamics simulations predict that isoform-specific residues support distinct intramolecular interactions in SERCA2a and SERCA1a. Our experimental observations further indicate that isoform-specific intramolecular interactions are functionally relevant, and may explain the kinetic differences between SERCA2a and SERCA1a.


Subject(s)
Heart/physiology , Sarcoplasmic Reticulum Calcium-Transporting ATPases/chemistry , Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism , Amino Acid Sequence , Animals , Models, Molecular , Molecular Dynamics Simulation , Protein Conformation , Protein Processing, Post-Translational , Sequence Homology , Swine
15.
J Clin Immunol ; 43(7): 1660-1670, 2023 10.
Article in English | MEDLINE | ID: mdl-37365453

ABSTRACT

PURPOSE: Anti-interferon gamma antibody (AIGA) is a rare cause of adult onset immunodeficiency, leading to severe disseminated opportunistic infections with varying outcomes. We aimed to summarize the disease characteristics and to explore factors associated with disease outcome. METHODS: A systematic literature review of AIGA associated disease was conducted. Serum-positive cases with detailed clinical presentations, treatment protocols, and outcomes were included. The patients were categorized into controlled and uncontrolled groups based on their documented clinical outcome. Factors associated with disease outcome were analyzed with logistic regression models. RESULTS: A total of 195 AIGA patients were retrospectively analyzed, with 119(61.0%) having controlled disease and 76 (39.0%) having uncontrolled disease. The median time to diagnosis and disease course were 12 months and 28 months, respectively. A total of 358 pathogens have been reported with nontubercular mycobacterium (NTM) and Talaromyces marneffei as the most common pathogens. The recurrence rate was as high as 56.0%. The effective rates of antibiotics alone, antibiotics with rituximab, and antibiotics with cyclophosphamide were 40.5%, 73.5%, and 75%, respectively. In the multivariate logistic analysis, skin involvement, NTM infection, and recurrent infections remained significantly associated with disease control, with ORs of 3.25 (95% CI 1.187 ~ 8.909, P value = 0.022), 4.74 (95% CI 1.300 ~ 17.30, P value = 0.018), and 0.22 (95% CI 0.086 ~ 0.551, P value = 0.001), respectively. The patients with disease control had significant AIGA titer reduction. CONCLUSIONS: AIGA could cause severe opportunistic infections with unsatisfactory control, particularly in patients with recurrent infections. Efforts should be made to closely monitor the disease and regulate the immune system.


Subject(s)
Immunologic Deficiency Syndromes , Mycobacterium Infections, Nontuberculous , Opportunistic Infections , Humans , Adult , Mycobacterium Infections, Nontuberculous/diagnosis , Retrospective Studies , Reinfection/complications , Reinfection/drug therapy , Autoantibodies , Interferon-gamma , Immunologic Deficiency Syndromes/diagnosis , Immunologic Deficiency Syndromes/drug therapy , Immunologic Deficiency Syndromes/epidemiology , Opportunistic Infections/drug therapy , Opportunistic Infections/complications , Anti-Bacterial Agents/therapeutic use
16.
Brief Bioinform ; 22(6)2021 11 05.
Article in English | MEDLINE | ID: mdl-34180984

ABSTRACT

Targeting the interaction between severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2)-receptor-binding domain (RBD) and angiotensin-converting enzyme 2 (ACE2) is believed to be an effective strategy for drug design to inhibit the infection of SARS-CoV-2. Herein, several ultrashort peptidase inhibitors against the RBD-ACE2 interaction were obtained by a computer-aided approach based on the RBD-binding residues on the protease domain (PD) of ACE2. The designed peptides were tested on a model coronavirus GX_P2V, which has 92.2 and 86% amino acid identity to the SARS-CoV-2 spike protein and RBD, respectively. Molecular dynamics simulations and binding free energy analysis predicted a potential binding pocket on the RBD of the spike protein, and this was confirmed by the specifically designed peptides SI5α and SI5α-b. They have only seven residues, showing potent antiviral activity and low cytotoxicity. Enzyme-linked immunosorbent assay result also confirmed their inhibitory ability against the RBD-ACE2 interaction. The ultrashort peptides are promising precursor molecules for the drug development of Corona Virus Disease 2019, and the novel binding pocket on the RBD may be helpful for the design of RBD inhibitors or antibodies against SARS-CoV-2.


Subject(s)
Angiotensin-Converting Enzyme 2/chemistry , COVID-19 Drug Treatment , Peptides/chemistry , SARS-CoV-2/drug effects , Spike Glycoprotein, Coronavirus/antagonists & inhibitors , Angiotensin-Converting Enzyme 2/antagonists & inhibitors , Angiotensin-Converting Enzyme 2/genetics , Antiviral Agents/chemistry , Binding Sites/drug effects , COVID-19/genetics , COVID-19/virology , Drug Design , Humans , Molecular Dynamics Simulation , Peptides/genetics , Peptides/therapeutic use , Protein Binding/drug effects , Protein Domains/drug effects , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics
17.
Phys Rev Lett ; 131(11): 113002, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37774266

ABSTRACT

When a charged particle penetrates through an optical interface, photon emissions emerge-a phenomenon known as transition radiation. Being paramount to fundamental physics, transition radiation has enabled many applications from high-energy particle identification to novel light sources. A rule of thumb in transition radiation is that the radiation intensity generally decreases with the decrease of particle velocity v; as a result, low-energy particles are not favored in practice. Here, we find that there exist situations where transition radiation from particles with extremely low velocities (e.g., v/c<10^{-3}) exhibits comparable intensity as that from high-energy particles (e.g., v/c=0.999), where c is the light speed in free space. The comparable radiation intensity implies an extremely high photon extraction efficiency from low-energy particles, up to 8 orders of magnitude larger than that from high-energy particles. This exotic phenomenon of low-velocity-favored transition radiation originates from the interference of the excited Ferrell-Berreman modes in an ultrathin epsilon-near-zero slab. Our findings may provide a promising route toward the design of integrated light sources based on low-energy electrons and specialized detectors for beyond-standard-model particles.

18.
Phys Rev Lett ; 131(11): 110802, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37774301

ABSTRACT

The passive approach to quantum key distribution (QKD) consists of removing all active modulation from the users' devices, a highly desirable countermeasure to get rid of modulator side channels. Nevertheless, active modulation has not been completely removed in QKD systems so far, due to both theoretical and practical limitations. In this Letter, we present a fully passive time-bin encoding QKD system and report on the successful implementation of a modulator-free QKD link. According to the latest theoretical analysis, our prototype is capable of delivering competitive secret key rates in the finite key regime.

19.
J Neural Transm (Vienna) ; 130(10): 1219-1230, 2023 10.
Article in English | MEDLINE | ID: mdl-37495840

ABSTRACT

More than half of stroke patients experience sensory dysfunction that affects their quality of life. Previous training modalities are ineffective in improving sensory function. In contrast, non-invasive brain stimulation (NIBS) is a new promising intervention for stroke rehabilitation. The aim of this meta-analysis was to summarize the current effectiveness of NIBS in the treatment of post-stroke sensory dysfunction. Articles published in PubMed, Web of Science, Embase, China National Knowledge Infrastructure (CNKI), Chinese scientific journals full-text database (VIP), and Wanfang database from the inception to March 8, 2023 were searched. There were no restrictions on language. A total of 14 RCTs were included (combined n = 804). Moderate-quality evidence suggested that NIBS significantly improved sensory function after stroke, and significant effects were observed up to 1 year after the intervention. In subgroup analysis, treatment with transcranial direct current stimulation (tDCS) or repetitive transcranial magnetic stimulation (rTMS) was significantly more effective than controls for recovery of sensory function in stroke patients. Stimulation of the primary motor cortex (M1), primary somatosensory cortex (S1) or M1 + S1 stimulation sites significantly improved sensory function. NIBS for sensory dysfunction showed significant therapeutic potential in patients with different stages of stroke. No significant effects were observed in subjects with less than 10 NIBS stimulations. Significant therapeutic effects were observed with either high-frequency or low-frequency rTMS.


Subject(s)
Brain , Stroke , Transcranial Direct Current Stimulation , Transcranial Magnetic Stimulation , Humans , Brain/physiopathology , Randomized Controlled Trials as Topic , Stroke/classification , Stroke/complications , Stroke/physiopathology , Stroke/therapy , Treatment Outcome
20.
Anal Bioanal Chem ; 415(18): 4401-4410, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36786836

ABSTRACT

Polarized light microscopy (PLM) is a common but critical method for pharmaceutical crystallinity characterization, which has been widely introduced for research purposes or drug testing and is recommended by many pharmacopeias around the world. To date, crystallinity characterization of pharmaceutical solids is restricted to laboratories due to the relatively bulky design of the conventional PLM system, while little attention has been paid to on-site, portable, and low-cost applications. Herein, we developed a smartphone-based polarized microscope with an ultra-miniaturization design ("hand-held" scale) for these purposes. The compact system consists of an optical lens, two polarizers, and a tailor-made platform to hold the smartphone. Analytical performance parameters including resolution, imaging quality of interference color, and imaging reproducibility were measured. In a first approach, we illustrated the suitability of the device for pharmaceutical crystallinity characterization and obtained high-quality birefringence images comparable to a conventional PLM system, and we also showed the great promise of the device for on-site characterization with high flexibility. In a second approach, we employed the device as a proof of concept for a wider application ranging from liquid crystal to environmental pollutants or tissues from plants. As such, this smartphone-based hand-held polarized light microscope shows great potential in helping pharmacists both for research purposes and on-site drug testing, not to mention its broad application prospects in many other fields.


Subject(s)
Smartphone , Reproducibility of Results , Microscopy, Polarization/methods , Pharmaceutical Preparations
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