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1.
J Forensic Sci ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38951918

ABSTRACT

Identification of vascular injuries is crucial for complete postmortem evaluation and understanding of trauma deaths by the Medical Examiner. Some vascular injuries are difficult to evaluate due to challenging anatomic locations, especially in the head and neck. Documenting injuries of the facial and vertebral arteries is challenging and necessitates time-consuming dissections that can create artifacts and disfigurement. In busy medical examiner offices with a significant number of traumatic injuries, finding a creative solution to employ reliable postmortem angiography is desirable. At the Office of the Chief Medical Examiner for the State of Maryland (OCME), we created and effectively implemented a selective angiography procedure using traditional indwelling Foley catheters and water-soluble barium swallow contrast to evaluate arterial injuries using either digital radiography or computed tomography imaging modalities. This technique and imaging interpretation can be performed by a medical examiner or forensic pathology fellow after basic technical training and basic radiology training. This study outlines the technique, methods, and utilization of the procedure and describes the findings of six deaths due to vascular lesions from different injury mechanisms and disease processes and describes the ease of implementation on a broader scale in busy Medical Examiner's offices.

2.
ACS Nano ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38952163

ABSTRACT

Ferroelectric materials display exotic polarization textures at the nanoscale that could be used to improve the energetic efficiency of electronic components. The vast majority of studies were conducted in two dimensions on thin films that can be further nanostructured, but very few studies address the situation of individual isolated nanocrystals (NCs) synthesized in solution, while such structures could have other fields of applications. In this work, we experimentally and theoretically studied the polarization texture of ferroelectric barium titanate (BaTiO3, BTO) NCs attached to a conductive substrate and surrounded by air. We synthesized NCs of well-defined quasicubic shape and 160 nm average size that conserve the tetragonal structure of BTO at room temperature. We then investigated the inverse piezoelectric properties of such pristine individual NCs by vector piezoresponse force microscopy (PFM), taking particular care to suppress electrostatic artifacts. In all of the NCs studied, we could not detect any vertical PFM signal, and the maps of the lateral response all displayed larger displacement amplitude on the edges with deformations converging toward the center. Using field phase simulations dedicated to ferroelectric nanostructures, we were able to predict the equilibrium polarization texture. These simulations revealed that the NC core is composed of 180° up and down domains defining the polar axis that rotate by 90° in the two facets orthogonal to this axis, eventually lying within these planes forming a layer of about 10 nm thickness mainly composed of 180° domains along an edge. From this polarization distribution, we predicted the lateral PFM response, which was revealed to be in very good qualitative agreement with the experimental observations. This work positions PFM as a relevant tool to evaluate the potential of complex ferroelectric nanostructures to be used as sensors.

3.
Small ; : e2403218, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38963069

ABSTRACT

In recent years, the implementation of energy-harvesting technology in medical equipment has attracted significant interest owing to its potential for self-powered and smart healthcare systems. Herein, the integration of a triboelectric nanogenerator (TENG) is proposed into an inhaler for energy-harvesting and smart inhalation monitoring. For this initially, barium sodium niobium oxide (Ba2NaNb5O15) microparticles (BNNO MPs) are synthesized via a facile solid-state synthesis process. The BNNO MPs with ferroelectricity and high dielectric constant are incorporated into polydimethylsiloxane (PDMS) polymer to make BNNO/PDMS composite films (CFs) for TENG fabrication. The fabricated TENG is operated in a contact-separation mode, and its electrical output performance is compared to establish the optimal BNNO MPs concentration. Furthermore, multi-wall carbon nanotubes (MWCNTs), a conductive filler material, are used to enhance the electrical conductivity of the CFs, thereby improving the electrical output performance of the TENG. The robustness/durability of the proposed BNNO-MWCNTs/PDMS CF-based TENG are investigated. The proposed TENG device is demonstrated to harvest electrical energy from mechanical motions via regular human activities and power portable electronics. The TENG is integrated into the inhaler casing to count the number of sprays remaining in the canister, send the notification to a smartphone via Bluetooth, and harvest energy.

4.
Article in English | MEDLINE | ID: mdl-38967116

ABSTRACT

Monocrystalline barium fluoride (BaF2), known for its exceptional optical properties in the infrared spectrum, exhibits anisotropy that influences surface quality and material removal efficiency during ultraprecision machining. This research explores the impact of anisotropy on the deformation and removal mechanisms of monocrystalline BaF2 by integrating nanoscratch tests with molecular dynamics (MD) simulations. Nanoscratch tests conducted on variously oriented monocrystalline BaF2 surfaces using a ramp loading mode facilitated the identification of surface cracks and a systematic description of material removal behaviors. This study elucidates the effect of crystal orientation on the ductile-brittle transition (DBT) of monocrystalline BaF2, further developing a critical depth prediction model for DBT on the (111) crystal plane to reveal the underlying anisotropy mechanisms. Moreover, nanofriction and wear behaviors in monocrystalline BaF2 are found to be predominantly influenced by scratch direction, crystal surface, and applied load, with the (110) and (100) planes showing pronounced frictional and wear anisotropy. A coefficient of friction model, accounting for the material's elastic recovery, establishes the intrinsic relationship between anisotropic friction and wear behaviors, the size effect, and scratch direction. Lastly, MD modeling of nanoscratched monocrystalline BaF2 reveals the diversity of dislocations and strain distributions along the (111) [-110] and [-1-12] crystal directions, offering atomic scale insights into the origins of BaF2 anisotropy. Thus, this study provides a theoretical foundation for the efficient processing of fluorine-based infrared optic materials exhibiting anisotropy.

5.
Materials (Basel) ; 17(11)2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38893964

ABSTRACT

Barium titanate (BaTiO3, BTO), conventionally used for dielectric and ferroelectric applications, has been assessed for biomedical applications, such as its utilization as a radiopacifier in mineral trioxide aggregates (MTA) for endodontic treatment. In the present study, BTO powders were prepared using the sol-gel process, followed by calcination at 400-1100 °C. The X-ray diffraction technique was then used to examine the as-prepared powders to elucidate the effect of calcination on the phase composition and crystalline size of BTO. Calcined BTO powders were then used as radiopacifiers for MTA. MTA-like cements were investigated to determine the optimal calcination temperature based on the radiopacity and diametral tensile strength (DTS). The experimental results showed that the formation of BTO phase was observed after calcination at temperatures of 600 °C and above. The calcined powders were a mixture of BaTiO3 phase with residual BaCO3 and/or Ba2TiO4 phases. The performance of MTA-like cements with BTO addition increased with increasing calcination temperature up to 1000 °C. The radiopacity, however, decreased after 7 days of simulated oral environmental storage, whereas an increase in DTS was observed. Optimal MTA-like cement was obtained by adding 40 wt.% 1000 °C-calcined BTO powder, with its resulting radiopacity and DTS at 4.83 ± 0.61 mmAl and 2.86 ± 0.33 MPa, respectively. After 7 days, the radiopacity decreased slightly to 4.69 ± 0.51 mmAl, accompanied by an increase in DTS to 3.13 ± 0.70 MPa. The optimal cement was biocompatible and verified using MG 63 and L929 cell lines, which exhibited cell viability higher than 95%.

6.
Am J Biol Anthropol ; : e24991, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38923412

ABSTRACT

OBJECTIVES: Nitrogen isotopes (δ15N) are widely used to study human nursing and weaning ages. Conventional methods involve sampling 1-mm thick sections of tooth dentine-producing an averaging effect that integrates months of formation. We introduce a novel protocol for measuring δ15N by multicollector secondary ion mass spectrometry (SIMS). MATERIALS AND METHODS: We sampled dentine δ15N on a weekly to monthly basis along the developmental axis in two first molars of healthy children from Australia and New Zealand (n = 217 measurements). Nitrogen isotope ratios were determined from measurements of CN- secondary molecular ions in ~35 µm spots. By relating spot position to enamel formation, we identified prenatal dentine, as well as sampling ages over more than 3 years. We also created calcium-normalized barium and strontium maps with laser ablation-inductively coupled plasma-mass spectrometry. RESULTS: We found rapid postnatal δ15N increases of ~2‰-3‰, during which time the children were exclusively breastfed, followed by declines as the breastfeeding frequency decreased. After weaning, δ15N values remained stable for several months, coinciding with diets that did not include meat or cow's milk; values then varied by ~2‰ starting in the third year of life. Barium did not show an immediate postnatal increase, rising after a few months until ~1-1.5 years of age, and falling until or shortly after the cessation of suckling. Initial strontium trends varied but both individuals peaked months after weaning. DISCUSSION: Developmentally informed SIMS measurements of δ15N minimize time averaging and can be precisely related to an individual's early dietary history.

7.
Nanomaterials (Basel) ; 14(12)2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38921868

ABSTRACT

Using magnetic nanoparticles (MNPs) for extracorporeal heating applications results in higher field strength and, therefore, particles of higher coercivity can be used, compared to intracorporeal applications. In this study, we report the synthesis and characterization of barium hexa-ferrite (BaFe12O19) nanoparticles as potential particles for magnetic heating. Using a precipitation method followed by high-temperature calcination, we first studied the influence of varied synthesis parameters on the particles' properties. Second, the iron-to-barium ratio (Fe/Ba = r) was varied between 2 and 12. Vibrating sample magnetometry, scanning electron microscopy and X-ray diffraction were used for characterization. A considerable influence of the calcination temperature (Tcal) was found on the resulting magnetic properties, with a decrease in coercivity (HC) from values above 370 kA/m for Tcal = 800-1000 °C to HC = 45-70 kA/m for Tcal = 1200 °C. We attribute this drop in HC mainly to the formation of entirely multi-domain particles at high Tcal. For the varying Fe/Ba ratios, increasing amounts of BaFe2O4 as an additional phase were detected by XRD in the small r (barium surplus) samples, lowering the particles' magnetization. A decrease in HC was found in the increased r samples. Crystal size ranged from 47 nm to 240 nm and large agglomerates were seen in SEM images. The reported particles, due to their controllable coercivity, can be a candidate for extracorporeal heating applications in the biomedical or biotechnological field.

8.
Cureus ; 16(5): e61111, 2024 May.
Article in English | MEDLINE | ID: mdl-38919233

ABSTRACT

Radiographic studies are used within healthcare on a routine basis to aid in the diagnosis and management of patients with a variety of health conditions. Barium sulfate is a contrast agent that may be used to enhance certain imaging studies. Although barium-contrasted studies are generally safe, they are not without risk for complications. Barium impactions, and their management, are infrequently reported in scientific literature. We present a case of a patient with barium impaction who presented at the emergency room after a fall from standing with associated symptoms of abdominal pain, weakness, and fatigue. A non-contrast computed tomography (CT) scan performed on presentation revealed the barium impaction, and initial attempts at conservative management were unsuccessful. A decompressive colonoscopy was performed without successful dissolution of the barium. Ultimately, the patient underwent exploratory laparotomy, which revealed a contained perforation of the sigmoid colon, and a successful partial colectomy with end colostomy was performed. This case study explores the surgical management of barium impaction in a comorbid patient.

9.
Biosens Bioelectron ; 261: 116505, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38885536

ABSTRACT

Surface enhanced Raman spectroscopy (SERS) utilizes the fingerprint features of molecular vibrations to identify and detect substances. However, in traditional single focus excitation scenarios, its signal collection efficiency of the objective is restricted. Furthermore, the uneven distribution of samples on the SERS substrate would result in poor signal stability, while the excitation power is limited to avoid sample damage. SERS detection system always requires precise adjustment of focal length and spot size, making it difficult for point-of-care testing applications. Here, we proposed a SERS microfluidic chip with barium titanate microspheres array (BTMA) embedded using vacuum self-assembled hot-pressing method for SERS detection with simultaneous enhancement of sensitivity and stability. Due to photonic nano-jets and directional antenna effects, high index microspheres are perfect micro-lens for effective light focusing and signal collecting. The BTMA can not only disperse excitation beam into an array of focal points covering the target uniformly with very low signal fluctuation, but enlarge the power threshold for higher signal intensity. We conducted a proof-of-principle experiment on chip for the detection of bacteria with immuno-magnetic tags and immuno-SERS tags. Together with magnetic and ultrasonic operations, the target bacteria in the flow were evenly congregated on the focal plane of BTMA. It demonstrated a limit of detection of 5 cells/mL, excellent signal reproducibility (error∼4.84%), and excellent position tolerance of 500 µm in X-Y plane (error∼5.375%). It can be seen that BTMA-SERS microfluidic chip can effectively solve the contradiction between sensitivity and stability in SERS detection.


Subject(s)
Biosensing Techniques , Lab-On-A-Chip Devices , Microspheres , Spectrum Analysis, Raman , Spectrum Analysis, Raman/instrumentation , Spectrum Analysis, Raman/methods , Biosensing Techniques/instrumentation , Limit of Detection , Equipment Design , Titanium/chemistry , Lenses , Escherichia coli/isolation & purification
10.
Biology (Basel) ; 13(6)2024 May 25.
Article in English | MEDLINE | ID: mdl-38927261

ABSTRACT

To clarify how the digestive tract of the weatherloach, Misgurnus anguillicaudatus, serves a dual function of digestion and respiration simultaneously, the histological structures of its digestive tract, the passage of digesta and air passing through its intestine and the rate of intestinal evacuation have been studied. The results indicate that the digestive tract is divided into five functional regions, i.e., esophagus, anterior intestine, middle intestine, posterior intestine and rectum. The diverse intestinal structures have the specialized function of coordinating digestion and respiration. An X-ray barium meal examination showed in the normal breathing state, the contents of the intestine are diffusely semifluid, and air is distributed as bubbles in the dorsal intestine 2 h after feeding. After 5 h, the contents accumulated in the mid and posterior intestine, and gas flowed above the contents as bundles. After 8 h, the intestinal food was basically evacuated. In the intestinal air-breathing restricted group, the contents of the intestine remained diffuse, and a large number of digesta entered and remained in the rectum after 5 h. After the inhibition was relieved, the contents of the rectum were rapidly discharged. Measurement of the intestinal evacuation rate in the intestine showed that the evacuation of the intestinal contents lagged behind that of the normal group in the air-breathing restricted group. Compared to the normal state and inhibited GAB (gastrointestinal air breathing), we could deduce that GAB could promote the movement of the intestine.

11.
Dysphagia ; 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935170

ABSTRACT

Clinical implementation of evidence-based practice (EBP) tools is a healthcare priority. The Dynamic Grade of Swallowing Toxicity (DIGEST) is an EBP tool developed in 2016 for videofluoroscopy in head and neck (H&N) oncology with clinical implementation as a goal. We sought to examine: (1) feasibility of clinical implementation of DIGEST in a national comprehensive cancer center, and (2) fidelity of DIGEST adoption in real-world practice. A retrospective implementation evaluation was conducted in accordance with the STARI framework. Electronic health record (EHR) databases were queried for all consecutive modified barium swallow (MBS) studies conducted at MD Anderson Cancer Center from 2016 to 2021. Implementation outcomes included: feasibility as measured by DIGEST reporting in EHR (as a marker of clinical use) and fidelity as measured by accuracy of DIGEST reporting relative to the decision-tree logic (penetration-aspiration scale [PAS], residue, and Safety [S] and Efficiency [E] grades). Contextual factors examined included year, setting, cancer type, MBS indication, and provider. 13,055 MBS were conducted by 29 providers in 7,842 unique patients across the lifespan in diverse oncology populations (69% M; age 1-96 years; 58% H&N cancer; 10% inpatient, 90% outpatient). DIGEST was reported in 12,137/13,088 exams over the 6-year implementation period representing 93% (95% CI: 93-94%) adoption in all exams and 99% (95% CI: 98-99%) of exams excluding the total laryngectomy population (n = 730). DIGEST reporting varied modestly by year, cancer type, and setting/provider (> 91% in all subgroups, p < 0.001). Accuracy of DIGEST reporting was high for overall DIGEST (incorrect SE profile 1.6%, 200/12,137), DIGEST-safety (incorrect PAS 0.4% 51/12,137) and DIGEST-efficiency (incorrect residue 1.2%, 148/12,137). Clinical implementation of DIGEST was feasible with high fidelity in a busy oncology practice across a large number of providers. Adoption of the tool across the lifespan in diverse cancer diagnoses may motivate validation beyond H&N oncology.

12.
Clin Endosc ; 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38872406

ABSTRACT

Background/Aims: Achalasia is a rare esophageal motility disease, for which peroral endoscopic myotomy (POEM) has emerged as a promising treatment option; however, recurrence remains a challenge. Timed barium esophagography (TBE) is a useful diagnostic tool and potential outcome predictor of achalasia. This study aimed to determine predictive tools for recurrence after POEM. Methods: This retrospective study enrolled achalasia patients who underwent POEM between January 2015 and December 2021. Patients were categorized into two groups using the 1-month post-POEM Eckardt scores and TBE: the discordant group (Eckardt score improved >50%, TBE decreased <50%) and the concordant group (both Eckardt score and TBE improved >50%). Recurrence was defined as a reincrease in the Eckardt score to more than three during follow-up. Results: Complete medical records were available in 30 patients who underwent POEM. Seventeen patients (56.7%) were classified into the discordant group, while 13 patients (43.3%) were in the concordant group. The overall recurrence rate was 11.9% at 1-year, increasing to 23.8% during the extended follow-up. The discordant group had a 6.87 fold higher recurrence rate than the concordant group (52.9% vs. 7.7%, p=0.017). Conclusions: These results strongly suggest that combining the Eckardt score with TBE can effectively predict recurrent achalasia after POEM. Patients in the discordant group had an elevated risk.

13.
J Diabetes Metab Disord ; 23(1): 11-26, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38932800

ABSTRACT

Background: Obesity and metabolic syndrome are global health concerns associated with development of different types of diseases and serious health threats in the long term. Their metabolic imbalance can be attributable to inherited and environmental factors. As a considerable environmental agent, heavy metals exposure can predispose individuals to diseases like obesity. This systematic review and meta-analysis aimed to evaluate the association between heavy metals exposure and the risk of obesity. Methods: PubMed/MEDLINE, EMBASE and Web of Science were systematically searched until December 17, 2022. Only observational studies that evaluated heavy metals exposure and obesity were included. Studies were excluded if they assessed maternal or prenatal exposure, the mixture of heavy metals and other chemicals, reported the association with overweight or other diseases, and undesirable study designs. The Joanna Briggs Institute checklist was used for quality assessment. The pooled adjusted odds ratio (aOR) and the pooled standardized mean difference (SMD) with their 95% confidence intervals (CIs) were calculated, respectively. The publication bias was evaluated using Egger's and Begg's tests. Results: Twenty studies (n = 127755), four case-control and sixteen analytical cross-sectional studies, were included. Lead exposure was significantly associated with a lower risk of obesity (aOR: 0.705, 95% CI: 0.498-0.997), while mercury (aOR: 1.458, 95% CI: 1.048-2.031) and barium (aOR: 1.439, 95% CI: 1.142-1.813) exposure increased the risk of obesity. No significant publication bias was found and the studies had a low risk of bias. Conclusion: Overall, lead exposure reduced obesity risk, while mercury and barium exposure raised it. Further large-scale observational studies are recommended to determine the roles of heavy metals in obesity.Study registration ID: CRD42023394865. Supplementary information: The online version contains supplementary material available at 10.1007/s40200-023-01307-0.

14.
Materials (Basel) ; 17(12)2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38930384

ABSTRACT

Barium zirconate (BaZrO3, BZO), which exhibits superior mechanical, thermal, and chemical stability, has been widely used in many applications. In dentistry, BZO is used as a radiopacifier in mineral trioxide aggregates (MTAs) for endodontic filling applications. In the present study, BZO was prepared using the sol-gel process, followed by calcination at 700-1000 °C. The calcined BZO powders were investigated using X-ray diffraction and scanning electron microscopy. Thereafter, MTA-like cements with the addition of calcined BZO powder were evaluated to determine the optimal composition based on radiopacity, diametral tensile strength (DTS), and setting times. The experimental results showed that calcined BZO exhibited a majority BZO phase with minor zirconia crystals. The crystallinity, the percentage, and the average crystalline size of BZO increased with the increasing calcination temperature. The optimal MTA-like cement was obtained by adding 20% of the 700 °C-calcined BZO powder. The initial and final setting times were 25 and 32 min, respectively. They were significantly shorter than those (70 and 56 min, respectively) prepared with commercial BZO powder. It exhibited a radiopacity of 3.60 ± 0.22 mmAl and a DTS of 3.02 ± 0.18 MPa. After 28 days of simulated oral environment storage, the radiopacity and DTS decreased to 3.36 ± 0.53 mmAl and 2.84 ± 0.27 MPa, respectively. This suggests that 700 °C-calcined BZO powder has potential as a novel radiopacifier for MTAs.

15.
Laryngoscope ; 2024 May 10.
Article in English | MEDLINE | ID: mdl-38727412

ABSTRACT

OBJECTIVE: Care of patients with dysphagia occurs at the intersection of several different medical specialties. Otolaryngologists are uniquely equipped to diagnose dysphagia given their specialized training, yet the extent to which otolaryngologists perform diagnostic procedures for dysphagia is unknown. The objective of this study was to characterize the specialty-level variation among providers performing diagnostic assessments for dysphagia. METHODS: We performed a retrospective, cross-sectional analysis of dysphagia care utilization among Medicare beneficiaries from 2013 to 2021 using the CMS Physician & Other Practitioners by Provider and Service dataset. American Association of Medical Colleges (AAMC) data reports were used to determine the total number of providers per specialty. For each procedure and specialty, the percentage of providers performing >10 procedures annually and the average annual number of procedures per performing provider (non-radiology) were calculated. RESULTS: We analyzed nine common dysphagia diagnostic procedures, including manometry, 24-h pH testing, flexible endoscopic evaluation of swallowing (FEES), and modified barium swallow study (MBSS). Mean 3.7 (SD 1.4) otolaryngologists (0.04% of practicing) performed manometry testing annually, compared to 493 (69.3) gastroenterologists (3.3%). Less than 1% of practicing otolaryngologists (37.8 (8.0) (0.04%)) and gastroenterologists (51.6 (8.4), 0.35%) performed 24-h pH testing annually. FEES testing was most commonly performed by otolaryngologists; however, only 48 (6.3) providers (0.51% of practicing) performed these procedures annually. For MBSS, fewer otolaryngologists (5.2 (1.0), 0.05%) perform these assessments than other medical specialties. Each otolaryngologist performed 110.7 (52.5) studies annually, compared to 200.1 (68.0) per gastroenterologist. CONCLUSION: Otolaryngologists represent a small fraction of providers performing dysphagia-related diagnostic procedures despite a unique training within our specialty to comprehensively diagnose and manage this condition. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

16.
Molecules ; 29(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38731470

ABSTRACT

This investigation is motivated by an interest in multiferroic BaFe12O19 (BFO), which combines advanced ferrimagnetic and ferroelectric properties at room temperature and exhibits interesting magnetoelectric phenomena. The ferroelectric charge storage properties of BFO are limited due to high coercivity, low dielectric constant, and high dielectric losses. We report the pseudocapacitive behavior of BFO, which allows superior charge storage compared to the ferroelectric charge storage mechanism. The BFO electrodes show a remarkably high capacitance of 1.34 F cm-2 in a neutral Na2SO4 electrolyte. The charging mechanism is discussed. The capacitive behavior is linked to the beneficial effect of high-energy ball milling (HEBM) and the use of an efficient dispersant, which facilitates charge transfer. Another approach is based on the use of conductive polypyrrole (PPy) for the fabrication of PPy-BFO composites. The choice of new polyaromatic dopants with a high charge-to-mass ratio plays a crucial role in achieving a high capacitance of 4.66 F cm-2 for pure PPy electrodes. The composite PPy-BFO (50/50) electrodes show a capacitance of 3.39 F cm-2, low impedance, reduced charge transfer resistance, enhanced capacitance retention at fast charging rates, and good cyclic stability due to the beneficial effect of advanced dopants, HEBM, and synergy of the contribution of PPy and BFO.

17.
Foods ; 13(9)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38731700

ABSTRACT

An experimental study is presented on the possibility of using the fluorescence from organic dyes as a broadband light source together with a monochromator for applications in excitation-emission matrix (EEM) fluorescence spectroscopy. A high-power single-chip light-emitting diode (LED) was chosen as an excitation source with a central output wavelength at 365 nm to excite a fluorescent solution of Coumarin 1 dye dissolved in ethanol. Two excitation configurations were investigated: direct excitation from the LED and excitation through an optical-fiber-coupled LED. A Czerny-Turner monochromator with a diffraction grating was used for the spectral tuning of the fluorescence. A simple method was investigated for increasing the efficiency of the excitation as well as the fluorescence signal collection by using a diffuse reflector composed of barium sulfate (BaSO4) and polyvinyl alcohol (PVA). As research objects, extra-virgin olive oil (EVOO), Coumarin 6 dye, and Perylene, a polycyclic aromatic hydrocarbon (PAH), were used. The results showed that the light-emitting-diode-induced fluorescence was sufficient to cover the losses on the optical path to the monochromator output, where a detectable signal could be obtained. The obtained results reveal the practical possibility of applying the fluorescence from dyes as a light source for food system analysis by EEM fluorescence spectroscopy.

18.
Polymers (Basel) ; 16(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38732670

ABSTRACT

A passive cooling method with great potential to lower space-cooling costs, counteract the urban heat island effect, and slow down worldwide warming is radiant cooling. The solutions available frequently require complex layered structures, costly products, or a reflective layer of metal to accomplish daytime radiative cooling, which restricts their applications in many avenues. Furthermore, single-layer paints have been used in attempts to accomplish passive daytime radiative cooling, but these usually require a compact coating or only exhibit limited cooling in daytime. In our study, we investigated and evaluated in daytime the surrounding cooling outcome with aid of one layer coating composed of BaSO4/TiO2 microparticles in various concentrations implanted in the PVDF-HF polymers on a concrete substrate. The 30% BaSO4/TiO2 microparticle in the PVDF-HF coating shows less solar absorbance and excessive emissivity. The value of solar reflectance is improved by employing micro-pores in the structure of PVDF polymers without noticeable effect on thermal emissivity. The 30% BaSO4/TiO2/PVDF coating is accountable for the hydrophobicity and proportionate solar reflection in the UV band, resulting in efficient solar reflectivity of about 95.0%, with emissivity of 95.1% and hydrophobicity exhibiting a 117.1° water contact angle. Also, the developed coating could cool to about 5.1 °C and 3.9 °C below the surrounding temperature beneath the average solar irradiance of 900 W/m-2. Finally, the results demonstrate that the 30% BaSO4/TiO2/PVDF-HF microparticle coating illustrates a typical figure of merit of 0.60 and is also capable of delivering outstanding dependability and harmony with the manufacturing process.

19.
Int J Biol Macromol ; 271(Pt 1): 132394, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38761905

ABSTRACT

The treatment of peripheral nerve injury is a clinical challenge that tremendously affected the patients' health and life. Anisotropic topographies and electric cues can simulate the regenerative microenvironment of nerve from physical and biological aspects, which show promising application in nerve regeneration. However, most studies just unilaterally emphasize the effect of sole topological- or electric- cue on nerve regeneration, while rarely considering the synergistic function of both cues simultaneously. In this study, a biomimetic-inspired piezoelectric topological ovalbumin/BaTiO3 scaffold that can provide non-invasive electrical stimulation in situ was constructed by combining piezoelectric BaTiO3 nanoparticles and surface microtopography. The results showed that the incorporation of piezoelectric nanoparticles could improve the mechanical properties of the scaffolds, and the piezoelectric output of the scaffolds after polarization was significantly increased. Biological evaluation revealed that the piezoelectric topological scaffolds could regulate the orientation growth of SCs, promote axon elongation of DRG, and upregulate the genes expression referring to myelination and axon growth, thus rapidly integrated chemical-mechanical signals and transmitted them for effectively promoting neuronal myelination, which was closely related to peripheral neurogenesis. The study suggests that the anisotropic surface topology combined with non-invasive electronic stimulation of the ovalbumin/BaTiO3 scaffolds possess a promising application prospect in the repair and regeneration of peripheral nerve injury.


Subject(s)
Barium Compounds , Ovalbumin , Schwann Cells , Tissue Scaffolds , Titanium , Tissue Scaffolds/chemistry , Animals , Titanium/chemistry , Barium Compounds/chemistry , Anisotropy , Ganglia, Spinal/cytology , Rats , Biomimetic Materials/chemistry , Nerve Regeneration
20.
Acad Forensic Pathol ; 14(2): 62-73, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38778897

ABSTRACT

Introduction: In this study we microscopically investigated, for the first time ever, the colorimetric detectability of barium of gunshot residues (GSR) on cadaveric human skin with gunshot wounds. Methods: For this purpose we used two different colorimetric techniques known in the literature, namely 0.2% sodium rhodizonate (Na-R-Ba 0.2%) and sodium rhodizonate in alcoholic environment (Na-R-Ba OH 0.2%). At the same time, we have also coupled it with scanning electron microscopy with energy dispersive X-ray (SEM/EDX) analysis and the colorimetric study for the detection of lead of GSR. These techniques were applied to 16 victims who died from gunshot injuries, as well as to a control group. Results: SEM/EDX demonstrated the presence of lead in all cases and barium in 11 of the 16 cases. The subsequent colorimetric technique with Na-R-Ba 0.2% did not show the barium of GSR in any case, unlike the Na-R-Ba OH 0.2% technique. This latter, in fact, has demonstrated the presence of this metal in 2 cases (18%). No microscopic case of false positive was recorded. Conclusion: The evidence obtained with Na-R-Ba OH 0.2% makes this method, applied here for the first time ever, worthy of further study. Meanwhile, although this technique can certainly be applied, it cannot be separated from the contextual colorimetric investigation for lead and the use of more sophisticated techniques.

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