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Hand-arm vibration, noise, temperature and static load--an experimental study of peripheral circulation while operating chain-saws.

From the viewpoint of elucidating the etiological mechanism of vibration-induced white finger (VWF), a model experiment was designed using a chain-saw under laboratory conditions. Finger skin temperature and finger blood flow were measured simultaneously as indicators of peripheral circulatory movement, using a thermister and an apparatus for measuring tissue blood flow based on the thermal diffusion method. In the first project (Experiment A), five healthy subjects operated a chain-saw at a high working speed with-out actually cutting anything. In the second project (Experiment B), seven heal…

[A multicenter study on vibrating mesh nebulization of pulmonary surfactant for treating respiratory distress syndrome in preterm infants].

OBJECTIVES: To evaluate the efficacy of noninvasive ventilation combined with vibrating mesh nebulization of pulmonary surfactant (PS) in preterm infants with respiratory distress syndrome (RDS) and to identify predictors of treatment failure. METHODS: Preterm infants with RDS (gestational age >28 weeks, birth weight >1 000 g) admitted to neonatal intensive care units at 12 hospitals between June 2023 and November 2024 were prospectively enrolled. All infants initially received nasal continuous positive airway pressure and were treated with PS administered via vibrating mesh nebulization. Inf

Vibrational Spectra of Anionic Polycyclic Aromatic Hydrocarbons in the CH Stretching Region: Anthracene, Pyrene, Perylene, and Fluoranthene.

The CH stretching region of the infrared spectra of polycyclic aromatic hydrocarbon radical anions (2700-3100 cm-1) is characterized by complicated band patterns that defy straightforward assignments from harmonic calculations. We compare experimental infrared photodissociation spectra of argon-tagged anthracene, pyrene, perylene, and fluoranthene anions with spectra computed using different methods in the framework of vibrational perturbation theory, starting from electronic structure calculations based on density functional theory. We trace the complex behavior in the CH stretching region to…

The Impact of Wheelset Eccentricity on High-Order Polygonal Wear Based on the Theory of Frictional Self-Excited Vibration.

According to investigation, the wheelset generally appears in a mass eccentric condition. Therefore, the finite element model of a wheelset-track system with mass eccentricity was established in this study to investigate the dynamic response characteristics based on the frictional self-excited vibration theory. The research results show that, when the frictional self-excited vibration of the wheelset-track system occurs, the unstable vibration characteristics of the wheelset-track system corresponding to different dynamic imbalance values are almost the same. That is, the magnitude of the dyna…

Spontaneous Raman Scattering under Vibrational Strong Coupling: The Critical Role of Polariton Spatial Mode Coherence.

Resonant coupling of a vibration to a cavity mode has been reported to dramatically modify spontaneous Raman scattering, but subsequent studies have produced conflicting results. In this Letter, we develop a microscopic quantum framework that captures the spatial structure of polaritonic modes. In a homogeneously filled cavity, spatial overlap between polaritons and cavity resonances enforces selection rules that suppress the initially reported polaritonic Raman peaks, consistent with most experiments. In contrast, for a quasi-two-dimensional (2D) molecular layer, these rules are lifted, yield…

Synergistic Vibrational Suppression and Aggregation Control via a Rigid Dimeric Acceptor for 21.13% Organic Solar Cells.

The efficiency bottleneck of organic solar cells (OSCs) is predominantly hindered by severe non-radiative energy loss (ΔE3), which primarily originates from strong electron-phonon coupling and detrimental charge recombination into darker state traps. Herein, we designed and synthesized a highly rigid and polarized dimeric acceptor, DY-SO by incorporating a sulfone bridged unit. It is revealed that the sulfone bridge's steric hindrance restricts backbone torsion and suppresses molecular vibration, enabling DY-SO with significantly reduced reorganization energy compared to small molecule L8-BO, …

Elucidating Nonradiative Relaxation of Charge-Transfer-Type Thermally Activated Delayed Fluorescence Emitters: The Vibrational Effect.

The S1/S0 nonradiative decay rate (kNRS) plays a key role in determining emission efficiency of thermally activated delayed fluorescence (TADF) emitters, yet the involvement of numerous vibrational modes often makes it challenging to elucidate vibrational effect on kNRS. Here, we investigate S1/S0 nonradiative decay in four prototypical charge-transfer (CT) TADF emitters, PXZ-TRZ, DMAC-TRZ, PXZ-DPS, and DMAC-DPS, using time-resolved spectroscopy, theoretical calculations, and vibrational analysis. Despite comparable CT character, emitters exhibit fluorescence quantum yields differing by up to …

From vibrations to function: Spectroscopic detection and quantification of π-π stacking in drug-responsive protein complexes.

Aromatic π-π stacking interactions are fundamental to protein architecture, molecular recognition, and drug efficacy, yet directly quantifyi … 49-ACE2 cells. Complementary density functional theory revealed electron density rearrangements and vibrational coupling patterns unique to stacked aromatic residues. This integrated spectroscopic-computational approach enables quantitative probing of π-π stacking in native-like protein environments and positioning TRIP as a generalizable tool for designing …

A novel scanning tunnelling microscope head with a double-piezo-tube nested scanner for operation in a vibrational magnet.

Coarse stepping motor and imaging scanner are the most important components of the scanning tunnelling microscope (STM). In traditional STMs … K, as well as the atomic images of HOPG obtained at changing magnetic fields from 0 T to 12 T in a vibrational magnet, proving new STM's high stability under low temperature and high magnetic fields.

Vibrational Spin-Orbit Coupling Contributions to Excited-State Decay of Ligand-to-Ligand Charge Transfer States.

Controlling excited-state relaxation processes is important in a variety of photochemical and photophysical processes, including the generation of ground- and excited-state spin polarization for quantum information science applications. Here, we address how specific static distortions, based on vibrational spin-orbit active modes at C2v symmetry determined by group theory, in a series of low-symmetry ligand-to-ligand charge transfer complexes enable direct spin-orbit coupling contributions to T1 → S0 excited-state decay. These results are used to address spin-vibronic coupling contributions to…

Theoretical-computational modeling of the vibrational chirality of interacting chromophores: VCD signal and equilibrium properties of excitonic clusters.

In this work, we extend the perturbed matrix method combined with molecular dynamics simulations, to the modeling of Vibrational Circular Dichroism (VCD) spectra, including non-covalent excitonic coupling among distinct molecular chromophores. The method is applied to (R)-propylene oxide as a benchmark system, comparing infinite-dilution conditions with highly concentrated solutions in water and carbon tetrachloride. The calculated VCD spectra show very good agreement with experimental data and only weak concentration dependence. However, analysis of the excitonic eigenstates reveals the forma…

Measured active rotational-vibrational energy levels (MARVEL) analysis of high-resolution rovibrational spectra of H12C14N.

Studying the rovibrational spectra of hydrogen cyanide (HCN) has become increasingly relevant due to growing concerns about the molecule's environmental and health risks and its special role in astronomy. Empirical rovibrational energy levels are determined based on the MARVEL (Measured Active Rotational-Vibrational Energy Levels) protocol for H12C14N, the most abundant HCN isotopologue. The spectroscopic analysis is based on 23 225 measured transitions, of which 14 728 are unique, collected from 39 literature sources. In contrast to most previous MARVEL studies, which utilized a very large nu…

Effects of low-magnitude high-frequency vibration on proliferation and cartilage phenotype of chondrocytes in the rat mandibular condyle.

OBJECTIVE: This study explored low-magnitude high-frequency (LMHF) mechanical vibration as a strategy to expand mandibular condylar chondrocyte (MCC) populations with enhanced chondrogenic phenotypes, providing high-quality cellular resources for cartilage tissue engineering. DESIGN: Primary MCCs from 3-week-old Sprague-Dawley rat condylar cartilage were subjected to LMHF vibration stimulation (0.49 g, 40 Hz) using a GJX-5 vibration device. Cell proliferation was evaluated via lactate dehydrogenase (LDH) assay and flow cytometry-based cell cycle analysis. The maintenance and enhancement of th…

The endocrine pathway during whole body vibration modulates the immune system and the osteogenesis in postmenopausal women with osteoporosis.

BACKGROUND: Osteoimmunology is an interdisciplinary field that investigates the interaction between the immune and skeletal systems in the context of immune regulation of bone remodeling. However, to date, osteoimmunology has not been linked to the broader systemic regulation of osteogenesis during physical exercise. Whole-body vibration (WBV) exercise initiates systemic sensory, endocrine, immune, and osteogenic responses. However, there is a gap in the understanding of the mechanisms underlying cross-system integration in WBV. OBJECTIVES: Our working hypothesis is that brain-immune modulati…

Deep learning-based multimodal fusion of vibrational spectroscopy and clinical data for aortic dissection diagnosis and prognosis.

BACKGROUND: Aortic dissection and myocardial infarction are two life-threatening acute cardiovascular conditions with similar clinical presentations but fundamentally different treatment strategies. Misdiagnosis between these diseases can severely endanger patient survival, highlighting the urgent need for efficient and non-invasive differential diagnostic methods. Vibrational spectroscopy, characterized by its non-invasiveness, high throughput, and molecular sensitivity, offers a promising approach for early biochemical disease identification. However, single spectral modalities are limited i…

The Relationship of Light Touch, Vibration, Muscle Strength, and Endurance With Balance, Gait, and Falling in Individuals With Multiple Sclerosis.

Multiple sclerosis is a progressive neurological disorder characterised by sensory and motor impairments. This study was conducted to investigate the relationship between lower extremity sensation, muscle strength and endurance, balance, gait, and risk of falling in patients with MS. Light touch sensation (LTS) was evaluated using the Semmes-Weinstein monofilament test (threshold: ≥2/3 correct responses). Vibration sensation was tested using a 128 Hz vibration fork. Muscle strength was measured in Newtons using a hand-held dynamometer, and core muscle endurance was assessed using a pressure bi…

Эффективность вибрации всего тела на гормональной реакции у людей с гормональными расстройствами: систематический обзор и метаанализ.

Цель. Цель этого систематического обзора заключается в изучении нынешней литературы о воздействии вибрации всего тела на гормональный уровень у людей с гормональными расстройствами. Методы. Систематический поиск проводился в шести электронных базах данных с целью получения результатов исследований воздействия вибрации всего тела на гормональный уровень у лиц с гормональными расстройствами. Полученные исследования оценивались на основе заранее установленных критериев отбора в два этапа: название и абстрактная фильтрация и полнотекстовая фильтрация. Качество проведенных исследований оценивалось

Совпадение в аннотации оригинала
Objective. This systematic review aims to examine the current literature on the effects of whole-body vibration on hormonal levels in individuals with hormonal disorders. Methods. A systematic search was performed on six electronic databases to retrieve studies examining the effects of whole-body vibration on hormonal levels in individuals with hormonal diso…

On-Ground Calibration of a Nano-G Accelerometer for Micro-Vibration Monitoring in Space on a Dual-Axis Indexing Device.

High-sensitivity accelerometers are essential for spacecraft micro-vibration monitoring. This study proposes a procedure to facilitate precise on-ground calibration of such accelerometers with a limited operational range by rotating to multiple positions with its input axis mounted along the horizontal tilt axis of a two-axis indexing device. Each single-axis accelerometer unit of a self-developed tri-axial nano-g accelerometer was respectively tested with its various reference axes along the rotation axis for identifying the parameters of their model equations including higher-order terms. Th…

Real-World Evidence of the Long-Term Clinical Utility of a Vibrating Capsule in the Management of Chronic Idiopathic Constipation.

INTRODUCTION: Pharmacological therapies for chronic idiopathic constipation (CIC) are useful, but many patients report dissatisfaction from … eased ( P < 0.0001). Safety analysis revealed that 4.6% of patients reported feeling a sensation of vibration, 1.8% reported abdominal pain and 0.64% reported diarrhea. DISCUSSION: In a community setting, the VC seems both effective and safe for long-term treatment of chronic constipation with diarrhea being notably uncommon.