Broadband THz emission of long pulses from photomixing process with optical chirped pulses.

Terahertz (THz) generation via photomixing on photoconductive antenna using twin delayed chirped pulses provides a long THz pulse with a narrow bandwidth. To generate a long pulse with a broad bandwidth, we propose a new, to the best of our knowledge, method that combines two long optical pulses with opposite chirps. The pulses exhibit temporal distributions of their instantaneous frequencies with opposite slopes.

Spine Injuries Sustained After Falls While Crossing the U.S.-Mexico Border.

This study is to report the demographics, incidence, and patterns of spinal injuries associated with border crossings resulting from a fall from a significant height. A retrospective cohort study was performed at a Level I trauma center from January 2016 to December 2021 to identify all patients who fell from a significant height while traversing the U.S.

Terahertz diffractive imaging with saturated data inpainting.

Multiplane iterative phase retrieval is a promising approach to diffraction imaging, which accurately determines the topographic and internal characteristics of various objects. Nevertheless, the detection systems used often have a limited dynamic range, resulting in overexposure of recorded intensity distributions. In this Letter, we present a novel, to the best of our knowledge, reconstruction algorithm that inpaints saturated areas on the measured intensity datasets and reliably retrieves wave complex amplitude.

Terahertz Nondestructive Testing with Ultra-Wideband FMCW Radar.

This paper presents the development, performance, integration, and implementation of a 150 GHz FMCW radar based on a homodyne harmonic mixing scheme for noncontact, nondestructive testing. This system offers high-dynamic-range measurement capabilities up to 100 dB and measurement rates up to 7.62 kHz.

Perceptions of Antibiotic Use and Resistance: Are Antibiotics the Dentists' Anxiolytics?

Background: Antibiotic resistance is a global health crisis. The aim of this study was to explore dentists' perceptions of antibiotic resistance.

Methods: A qualitative method was used.

Use of the pericoronal tissue of impacted third molar in subgingival connective tissue autograft: A case report.

Introduction And Importance: The pericoronal tissue, or dental follicle, is a connective tissue found around impacted teeth crown. The dental follicle is involved in odontogenesis, dental eruption and periodontogenesis.

Case Presentation: A young woman presented a vestibular U-shaped periodontal recession localized in tooth 26.

Terahertz refractive index-based morphological dilation for breast carcinoma delineation.

This paper reports investigations led on the combination of the refractive index and morphological dilation to enhance performances towards breast tumour margin delineation during conserving surgeries. The refractive index map of invasive ductal and lobular carcinomas were constructed from an inverse electromagnetic problem. Morphological dilation combined with refractive index thresholding was conducted to classify the tissue regions as malignant or benign.

CYP1A2 and tobacco interaction: a major pharmacokinetic challenge during smoking cessation.

Smoking cessation is underestimated in terms of drug interactions. Abrupt smoking cessation is common in cases of emergency hospitalization and restrictions of movement. Tobacco is a known cytochrome P450 1A2 (CYP1A2) inducer, its consumption and withdrawal can lead to major pharmacokinetic drug interactions.

Oral management in a patient with Gardner-Diamond Syndrome: A case report.

Introduction: Gardner-Diamond Syndrome (GDS) is rare. It is characterized by the spontaneous formation of painful erythematous skin lesions that develop into ecchymoses within 24 h and then disappear progressively over days to weeks. The complications can be serious.

Heterotrimetallic {LnOVPt} complexes with antiferromagnetic Ln-V coupling and magnetic memory.

The new PtVO(SOCR)4 lantern complexes, 1 (R = CH3) and 2 (R = Ph) behave as neutral O-donor ligands to Ln(OR)3 with Ln = Ce, Nd. Four heterotrimetallic complexes with linear {LnOVPt} units were prepared: [Ln(ODtbp)3{PtVO(SOCR)4}] (Ln = Ce, 3Ce (R = CH3), 4Ce (R = Ph); Nd, 3Nd (R = CH3), 4Nd (R = Ph); ODtbp = 2,6-ditertbutylphenolate). Magnetic characterization confirms slow magnetic relaxation behaviour and suggests antiferromagnetic coupling across {Ln-O[double bond, length as m-dash]V} in all four complexes, with variations tunable as a function of Ln and R.

Terahertz phase retrieval imaging in reflection.

Terahertz phase retrieval is a promising technique able to assess the complex diffracted wave properties through an iterative processing algorithm. In this Letter, we demonstrate the implementation of this technique in reflection geometry with a continuous wave acquisition system working at 0.287 THz.

A Versatile Illumination System for Real-Time Terahertz Imaging.

Terahertz technologies are attracting strong interest from high-end industrial fields, and particularly for non-destructive-testing purposes. Currently lacking compactness, integrability as well as adaptability for those implementations, the development and commercialisation of more efficient sources and detectors progressively ensure the transition toward applicative implementations, especially for real-time full-field imaging. In this work, a flexible illumination system, based on fast beam steering has been developed and characterized.

Brain abscesses and intracranial empyema due to dental pathogens: Case series.

Introduction: Spontaneous brain abscess and intracranial empyema are rare but life-threatening diseases. They can result from potential complications of oral chronic infections. Given the similarity between most of the germs commonly found both in cerebral abscess and in oral cavity and its anatomic proximity, the oral cavity represents a major source of cerebral infections.

Guided terahertz pulse reflectometry with double photoconductive antenna.

Developments toward the implementation of a terahertz pulse imaging system within a guided reflectometry configuration are reported. Two photoconductive antennas patterned on the same LT-GaAs active layer in association with a silica pipe hollow-core waveguide allowed us to obtain a guided optics-free imager. Besides working in a pulsed regime, the setup does not require additional optics to focus and couple the terahertz pulses into the waveguide core, simplifying the global implementation in comparison with other reported guided terahertz reflectometry systems.

Antibiotic use and resistance: a nationwide questionnaire survey among French dentists.

The aim of this survey was to describe the attitudes and self-reported practices of French dentists towards antibiotic use and resistance and to compare practices with national guidelines. A nationwide cross-sectional internet-based survey was conducted among the 41,800 French dentists. The online questionnaire was distributed through professional networks from April 2017 to April 2018.

A Systematic Review of Ion Radiotherapy in Maintaining Local Control Regarding Atypical and Anaplastic Meningiomas.

Objective: Atypical and anaplastic meningiomas, unlike their benign counterparts, are highly aggressive, locally destructive, and likely to recur after treatment. These diseases are difficult to definitively treat with traditional radiotherapy without injuring adjacent brain parenchyma. The physical properties of ion radiotherapy allows for treatment plans that avoid damaging critical neural structures.

Multimodal Optical Diagnostics of Glycated Biological Tissues.

Diabetes mellitus is a metabolic disorder characterized by chronic hyperglycemia accompanied by the disruption of carbohydrate, lipid, and proteins metabolism and development of long-term microvascular, macrovascular, and neuropathic changes. This review presents the results of spectroscopic studies on the glycation of tissues and cell proteins in organisms with naturally developing and model diabetes and in vitro glycated samples in a wide range of electromagnetic waves, from visible light to terahertz radiation. Experiments on the refractometric measurements of glycated and oxygenated hemoglobin in broad wavelength and temperature ranges using digital holographic microscopy and diffraction tomography are discussed, as well as possible application of these methods in the diabetes diagnostics.

Shape-from-focus for real-time terahertz 3D imaging.

Thanks to significant advances in real-time terahertz imaging in terms of resolution and image quality, adapting and extending optical methods for 3D imaging at the millimeter scale is now promising. The shape-from-focus algorithm is a post-processing tool used in optical microscopy to reconstruct the external shape surface of a convex surface object. Images acquired at different distances from the object-side focal plane are implemented in this algorithm.

Terahertz Spectroscopy and Quantum Mechanical Simulations of Crystalline Copper-Containing Historical Pigments.

Terahertz spectroscopy, a noninvasive and nondestructive analytical technique used in art conservation and restoration, can provide compelling data concerning the composition and condition of culturally valuable and historical objects. Terahertz spectral databases of modern and ancient artists' pigments exist but lack explanations for the origins of the unique spectral features. Solid-state density functional theory simulations can provide insight into the molecular and intermolecular forces that dominate the observed absorption features as well as reveal deviations from simple harmonic vibrational behavior that can complicate these spectra.