Inverse Raman Scattering in Femtosecond Broadband Transient Absorption Experiments

This chapter reports on one of the nonlinear spectral features, the inverse Raman scattering (IRS), observed upon the interaction of ultrafast‐pulsed lasers in a Raman‐active medium. Hereby, a comprehensive theoretical description of the IRS is exposed. Furthermore, the investigation carried out on synthetic eumelanin dispersions is addressed to show how the transient absorption measurements can be influenced by the IRS, if probing at energies close to Stokes and anti‐Stokes vibrational modes of the medium. A thorough analysis demonstrates that the IRS affects the sign of dynamics but not relaxation times. A specific kind of spectroscopy based on the IRS effect (ultrafast Raman loss spectroscopy) is eventually illustrated as valuable tool to characterize the structure of molecules and to investigate their dynamics during chemical reactions, even occurring at ultrafast timescales

A Cell-Based Nasal Model for Screening the Deposition, Biocompatibility and Transport of Aerosolized PLGA Nanoparticles

The olfactory region of the nasal cavity directly links the brain to the external environment, presenting a potential direct route to the central nervous system (CNS). However, targeting drugs to the olfactory region is challenging and relies on a combination of drug formulation, delivery device, and administration technique to navigate human nasal anatomy. In addition, in vitro and in vivo models utilized to evaluate the performance of nasal formulations do not accurately reflect deposition and uptake in the human nasal cavity. The current study describes the development of a respirable poly(lactic-co-glycolic acid) nanoparticle (PLGA NP) formulation, delivered via a pressurized metered dose inhaler (pMDI), and a cell-containing three-dimensional (3D) human nasal cast model for deposition assessment of nasal formulations in the olfactory region. Fluorescent PLGA NPs (193 ± 3 nm by dynamic light scattering) were successfully formulated in an HFA134a-based pMDI and were collected intact following aerosolization. RPMI 2650 cells, widely employed as a nasal epithelial model, were grown at the air-liquid interface (ALI) for 14 days to develop a suitable barrier function prior to exposure to the aerosolized PLGA NPs in a glass deposition apparatus. Direct aerosol exposure was shown to have little effect on cell viability. Compared to an aqueous NP suspension, the transport rate of the aerosolized NPs across the RPMI 2650 barrier was higher at all time points indicating the potential advantages of delivery via aerosolization and the importance of employing ALI cellular models for testing respirable formulations. The PLGA NPs were then aerosolized into a 3D-printed human nasal cavity model with an insert of ALI RPMI 2650 cells positioned in the olfactory region. Cells remained highly viable, and there was significant deposition of the fluorescent NPs on the ALI cultures. This study is a proof of concept that pMDI delivery of NPs is a viable means of targeting the olfactory region for nose-to-brain drug delivery (NTBDD). The cell-based model allows not only maintenance under ALI culture conditions but also sampling from the basal chamber compartment; hence, this model could be adapted to assess drug deposition, uptake, and transport kinetics in parallel under real-life settings.</p

Effect of Finish Line Design and Metal Alloy on The Marginal and Internal Gaps of Selective Laser Melting Printed Copings

Statement of problem Selective laser melting (SLM) technology has been introduced for printing metal dental restorations from Co-Cr base alloys or Au-Pt high noble alloys. However, information regarding the fit of restorations fabricated by using this technique is limited. Purpose The purpose of this in vitro study was to determine the effect of 3 different finish line designs on the marginal and internal gaps of metal copings made from a base (Co-Cr), high noble (Au-Pd-Ag), and noble alloy (Co-Pd) by using the SLM technology. Material and methods Three Ivorine right maxillary central incisors were prepared with a chamfer, deep chamfer, or shoulder finish line. The preparations were scanned by using a TRIOS scanner, and a total of 90 dies were printed using DPR 10 Resin (30×3 finish line designs). Ten SLM copings were fabricated for each margin design and metal alloy combination for a total of 90 copings (10×3 finish line designs×3 alloys). Copings were cemented onto dies using an autopolymerizing composite-resin luting material. All coping-die assemblies were sectioned buccolingually by using a low-speed diamond saw, and images were obtained by using an inverted bright field metallurgical microscope at ×100 magnification. Marginal and internal gaps were measured at 5 locations: buccal margin, midfacial, incisal, midlingual, and lingual margin. After gap measurements, representative specimens were embedded in autopolymerizing resin and prepared for metallographic examination. A 2-way multivariate analysis of variance (MANOVA) was conducted to determine the overall significance, followed by ANOVA for each dependent variable (α=.05). Results The results indicated that alloy type and finish line had a significant influence on marginal gap of copings (PPP=.337). No statistically significant interactions occurred. Base alloys were printed with almost no observable porosity, whereas noble and high noble alloys exhibited hot tears and porosity. Conclusions The finish line type did not influence the internal gap between copings and dies, whereas the alloy type influenced the marginal gap between copings and dies. SLM-fabricated Co-Cr copings on teeth prepared with a deep chamfer finish line demonstrated the lowest marginal gap

Magnetic response of core-shell cobalt ferrite nanoparticles at low temperature

Cobaltferritenanoparticles (size: 26±4nm) have been synthesized by coprecipitation route. The coercivity of nanoparticles follows a simple model of thermal activation of particle moments over the anisotropy barrier in the temperature range of 30–300K in accordance with Kneller’s law; however, at low temperatures

Improving Decision Support Systems with Machine Learning: Identifying Barriers to Adoption

Precision agriculture (PA) has been defined as a “management strategy that gathers, processes and analyzes temporal, spatial and individual data and combines it with other information to support management decisions according to estimated variability for improved resource use efficiency, productivity, quality, profitability and sustainability of agricultural production.” This definition suggests that because PA should simultaneously increase food production and reduce the environmental footprint, the barriers to adoption of PA should be explored. These barriers include: 1) the financial constraints associated with adopting DSS, 2) the hesitancy of farmers to change from their trusted advisor to a computer program often behaves as a black box, 3) questions about data ownership and privacy, and 4) the lack of a trained workforce to provide the necessary training to implement DSSs on individual farms. This paper also discusses the lessons learned from successful and unsuccessful efforts to implement DSSs, the importance of communication with end-users during DSS development, and potential career opportunities that DSSs are creating in PA

Optical aberrations following implantation of multifocal intraocular lenses: a systematic review and meta-analysis protocol

INTRODUCTION: Multifocal intraocular lens (IOLs) are used to restore vision at different focal distances. The technology of multifocal IOLs is continually advancing. Optical aberrations a property of lenses that causes spreading of light over a region resulting in a blurred or distorted image. This study aims to systematically review investigator measured and patient reported optical aberrations following implantation of multifocal IOLs during phacoemulsification surgery to treat presbyopia in adults. METHODS AND ANALYSIS: We will conduct an electronic database search for randomised controlled trials, prospective non-randomised studies, observational studies in Ovid MEDLINE, Ovid EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, Scopus and ClinicalTrials.gov in March 2021. Eligibility criteria will include quantitative articles written in English and containing data on optical aberrations. Two independent reviewers will screen titles and abstracts and extract data from full texts, reporting outcomes according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data extraction of key characteristics will be completed using customised forms. Methodological quality will be assessed using Cochrane Handbook 6.2. ETHICS AND DISSEMINATION: Ethics approval is not required for this review, as it will only include published data. Findings will be published in a peer-reviewed journal and disseminated across ophthalmic networks. We anticipate that the findings of this work will be of interest to multiple stakeholders: people who have undergone cataract surgery, eye health professionals, ophthalmic surgeons, device manufacturers and policy-makers. It will also inform researchers to where there are gaps in evidence and identify areas for future research. PROSPERO REGISTRATION NUMBER: CRD42021271050

Microbial load of rinsed and unrinsed body cavities of roe deer (Capreolus capreolus) on the killing day and after cold storage: A preliminary investigation

Ensuring good game meat hygiene is a challenge in the hunting supply chain. Game carcasses can be soiled with intestinal contents or other substances from the environment due to hunting and handling practices. This soiling can increase the microbial load (ML) of the carcass and the resulting game meat. The aim of this study was to investigate whether rinsing of soiled and unsoiled body cavities with drinking water can reduce the ML of carcasses. Carcasses of 23 roe deer (Capreolus capreolus) were processed, either rinsed (n = 12) or unrinsed (n = 11), and examined for ML. Swab and muscle samples were taken from the carcasses at killing day and after 3 days of cold storage. The levels of ML were comparable for the rinsed and unrinsed roe deer carcasses with an increase of Pseudomonas spp. during cold storage. Initial ML seems to be independent of visible soiling. Other factors affecting the initial ML should be determined in future studies

Exchange Bias and Vertical Shift in CoFe2O4 nanoparticles

Magnetic properties of core-shell cobalt ferrite nanoparticles 15 to 48nm prepared by a sol-gel route have been studied. It is shown that the coercivity follows non-monotonic size dependence varying as 1/d above the maximum (d is the particle size). Field cooled magnetization exhibited both horizontal (exchange bias) and vertical shifts. The exchange bias is understood as originating at the interface between a surface region with structural and spin disorder and a core ferrimagnetic region. The dependence of the exchange bias and vertical shifts on the particle sizes and cooling fields are found to have significant differences and the differences are explained in the light of recent results which suggest that both weakly and strongly pinned spins are present at the interface. It is suggested that the exchange bias is dominated by the weakly pinned spins while the vertical shift is affected by the strongly pinned ones.Comment: 2

Quantitative magnetic resonance imaging (qMRI) in Axial Spondyloarthritis

Imaging, and particularly magnetic resonance imaging (MRI), plays a crucial role in the assessment of inflammation in rheumatic disease, and forms a core component of the diagnostic pathway in axial spondyloarthritis (axSpA). However, conventional imaging techniques are limited by image contrast being non-specific to inflammation and a reliance on subjective, qualitative reader interpretation. Quantitative MRI (qMRI) methods offer scope to address these limitations and improve our ability to accurately and precisely detect and characterise inflammation, potentially facilitating a more personalised approach to management. Here, we review qMRI methods and emerging quantitative imaging biomarkers (QIBs) for imaging inflammation in axSpA. We discuss the potential benefits as well as the practical considerations that must be addressed in the movement toward clinical translation of QIBs