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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124960, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39180967

RESUMO

In this study, the molecular, electronic, and chemical properties of the drug hydrochlorothiazide (HCTZ) are determined after cocrystallization with 4-aminobenzoic acid (4-ABA). Analysis has been performed to understand how those variations lead to alteration of physical properties and chemical reactivity in the cocrystal HCTZ-4ABA. IR and Raman characterizations were performed along with quantum chemical calculations. A theoretical investigation of hydrogen bonding interactions in HCTZ-4ABA has been conducted using two functionals: B3LYP and wB97X-D. The results obtained by B3LYP and wB97X-D are compared which leads to the conclusion that B3LYP is the best applied function (density functional theory) to obtain suitable results for spectroscopy. The chemical reactivity descriptors are used to understand various aspects of pharmaceutical properties. Natural bond orbital (NBO) analysis and quantum theory of atoms (QTAIM) are used to analyze nature and strength of hydrogen bonding in HCTZ-4ABA. QTAIM analyzed moderate role of hydrogen bonding interactions in HCTZ-4ABA. The calculated HOMO-LUMO energy gap shows that HCTZ-4ABA is chemically more active than HCTZ drug. These chemical parameters suggest that HCTZ-4ABA is chemically more reactive and softer than HCTZ. The results of this study suggest that cocrystals can be a good alternative for enhancing physicochemical properties of a drug without altering its therapeutic properties.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124954, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39180970

RESUMO

We investigated the anharmonicity and intermolecular interactions of N-methylformamide (NMF) and di-N,N-methylformamide (DMF) in the neat liquid phase with particular interest in the amide bands. The vibrational spectra, complex refractive index, and complex electric permittivity were determined in in the mid- (MIR) and near-infrared (NIR) regions (11,500-560 cm-1; 870-17857 nm). Dispersion analysis was based on the Classical Damped Harmonic Oscillator (CDHO) and simultaneous modelling of the real and imaginary components of the spectra. This data delivered insights into the vibrational energy dissipation and self-association in liquid amides. Identification of the MIR and NIR bands was based on anharmonic GVPT2//B3LYP/6-311++G(d,p) calculations. DMF and NMF follow distinct self-association, evidenced in the MIR fingerprint by the two components of the νCO, the analog of the Amide I band. These conclusions are supported by the structural information derived from the NIR spectra. Furthermore, the contribution of overtones and combination bands in the MIR spectra of amides was examined. The conclusions on molecular interactions and structural dynamics of NMF and DMF contribute to a deeper understanding of the effects of changes in the local environment of the amide group.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124945, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39163768

RESUMO

Pd speciation induced by the combined effect of CO and water on Pd/SSZ-13 samples prepared by both impregnation and ion exchange was examined by FT-IR spectroscopy of CO adsorbed at room temperature and at liquid nitrogen temperature on anhydrous and hydrated samples. Starting from the literature findings related to the CO reducing effect on Pd cations, the present work gives precise spectroscopic evidences on how water is necessary in this process not only for compensating with H+ the zeolite exchange sites set free by Pd reduction, but also for mobilizing isolated Pd2+/Pd+ cations and making possible the reduction reactions. The aggregation of some Pd+ sites, just formed by the reduction and mobilized by the hydration, gives rise to the formation of Pd2O particles. Also, Pd0(100) sites are observed with CO on hydrated sample, formed by the aggregation and reduction of isolated Pd cations. Moreover, Pd0(111) sites are formed on the surface of PdOx particles during CO outgassing. The observation of the combined effect of water and CO allowed to define assignments of IR bands related to carbonyls of Pd in different oxidation states and coordination degrees.

4.
Sci Rep ; 14(1): 23189, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39369106

RESUMO

Carbon with depleted d13C (down to - 25.6‰ VPDB) found in > 3.7 billion year old metamorphic sediments from the Isua Supracrustal Belt, Southwestern Greenland, has been proposed to represent the oldest remains of life on Earth. Graphitic inclusions within garnet porphyroblasts from this locality have been shown to associate with elements consistent with biogenic remains. In this report, we focus on certain liquid inclusions found in the Isua garnets, characterizing their chemical composition using atomic force microscopy, AFM-based infrared spectroscopy, optical photothermal infrared spectroscopy, Raman spectroscopy, and time-of-flight secondary ion mass spectrometry. Our results show that the liquid inclusions contain functional groups consisting of carbon, nitrogen, and oxygen in a configuration similar to amide functional groups. We suspect that the amide groups formed from N, O and C-containing volatile components that were released from the original kerogenous material enclosed in the garnets, as this was graphitized during thermal maturation. This is consistent with the observed inclusion assemblage of solid graphitic and viscous fluid inclusions alike. Our observations are compatible with the inclusions forming from biogenic precursor material, and when considered alongside previous reports on the carbonaceous material in the Isua metamorphic sediments, these and our study collectively indicate that the carbonaceous material in the Isua metasediments represents the oldest traces of life on Earth.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39367983

RESUMO

There is an urgent need for improved methods for early screening and rapid diagnosis of cervical cancer since current conventional screening methods are plagued by operator subjectivity and unnecessary biopsies. IR808 is a tumour-targeting near-infrared (NIR) fluorescent dye that permits NIR imaging without the requirement of chemical conjugation. Our study investigates an IR808-based strategy for real-time monitoring of the cervix in vivo and rapid assessment of cervical specimens in vitro. We investigated the uptake of IR808 in vitro using normal cervical epithelial cells and three cervical cancer cell lines. The biodistribution of IR808 was examined in vivo via intravenous injection into tumour-bearing mice. Additionally, in vitro tissues were stained with IR808 to simulate the identification of cervical tumors in the clinical setting. Biocompatibility of the dye in both cellular and animal models was also examined. IR808 exhibited significant tumour-to-background ratios in fluorescence molecular imaging of in vivo tumors in nude mice. The application of NIR fluorescent dye IR808 in specific imaging screening, safe and non-invasive real-time monitoring, and rapid identification of cervical tumors from tissue specimens is expected to improve current screening methods for cervical cancer.

6.
ACS Appl Bio Mater ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352856

RESUMO

Infections resulting from microorganisms pose an ongoing global public health challenge, necessitating the constant development of novel antimicrobial approaches. Utilizing photocatalytic materials to generate reactive oxygen species (ROS) presents an appealing strategy for combating microbial threats. In alignment with this perspective, sodium titanate nanotubes were prepared by scalable hydrothermal method using TiO2 and NaOH. Ag, Au, and Ag/Au-modified titanate nanotubes (TNTs) were prepared by a cost-effective and simple ion-exchange method. All samples were characterized by XRD, FT-IR, HRTEM, and DLS techniques. HRTEM images indicated that the tubular structure was preserved in all TNTs even after the replacement of Na+ with Ag+ and/or Au3+ ions. The antibacterial activity in dark and sunlight conditions was evaluated using different bacterial strains, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The results showed that while a low bacterial count (∼log 5 cells per well) was used for inoculation, the TNTs exhibited no antibacterial activity against the three bacterial strains, regardless of whether they were tested under light or dark conditions. However, the plasmonic nanoparticle-decorated TNTs showed remarkable activity in the dark. Additionally, Ag/Au-TNTs demonstrated significantly higher activity in the dark compared with either Ag-TNTs or Au-TNTs alone. Notably, under dark conditions, the Au/Ag-TNTs achieved log reductions of up to 4.5 for P. aeruginosa, 5 for S. aureus, and 3.7 for E. coli. However, when exposed to sunlight, Au/Ag-TNTs resulted in a complete reduction (log reduction ∼9) for P. aeruginosa and E. coli. The combination of two plasmonic nanoparticles (Ag/Au) decorated on the surface of TNTs showed synergetic bactericidal activity under both dark and light conditions. Ag/Au-TNTs could be explored to design surfaces that are responsive to visible light and exhibit antimicrobial properties.

7.
Small ; : e2406718, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375992

RESUMO

Electrocatalytic nitrogen oxidation reaction (N2OR) offers a sustainable alternative to the conventional methods such as the Haber-Bosch and Ostwald oxidation processes for converting nitrogen (N2) into high-value-added nitrate (NO3 -) under mild conditions. However, the concurrent oxygen evolution reaction (OER) and inefficient N2 absorption/activation led to slow N2OR kinetics, resulting in low Faradaic efficiencies and NO3 - yield rates. This study explored oxygen-vacancy induced tin oxide (SnO2-Ov) as an efficient N2OR electrocatalyst, achieving an impressive Faradaic efficiency (FE) of 54.2% and a notable NO3 - yield rate (22.05 µg h-1 mgcat -1) at 1.7 V versus reversible hydrogen electrode (RHE) in 0.1 m Na2SO4. Experimental results indicate that SnO2-Ov possesses substantially more oxygen vacancies than SnO2, correlating with enhanced N2OR performance. Computational findings suggest that the superior performance of SnO2-Ov at a relatively low overpotential is due to reduced thermodynamic barrier for the oxidation of *N2 to *N2OH during the rate-determining step, making this step energetically favorable than the oxygen adsorption step for OER. This work demonstrates the feasibility of ambient nitrate synthesis on the soft acidic Sn active site and introduces a new approach for rational catalyst design.

8.
Chemistry ; : e202402743, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39355989

RESUMO

The structural variability of a compound class is an important criterion for the research into phosphor host lattices for phosphor-converted light-emitting diodes (pc-LEDs). Especially, nitridophosphates and the related class of imidonitridophosphates are promising candidates. Recently, the ammonothermal approach has opened a systematic access to this substance class with larger sample quantities. We present the successful ammonothermal synthesis of the imidonitridophosphate Ba4P4N8(NH)2:Eu2+. Its crystal structure is solved by X-ray diffraction and it crystallizes in space group Cc (no. 9) with lattice parameters a = 12.5250(3), b = 12.5566(4), c = 7.3882(2) Å and ß = 102.9793(10)°. For the first time, adamantane-type (imido)nitridophosphate anions [P4N8(NH)2]8- are observed next to metal ions other than alkali metals in a compound. The presence of imide groups in the structure and the identification of preferred positions for the hydrogen atoms are performed using a combination of quantum chemical calculations, Fourier-transform infrared, and solid-state NMR spectroscopy. Eu2+ doped samples exhibit cyan emission (λmax = 498 nm, fwhm = 50 nm/1981 cm-1) when excited with ultraviolet light with an impressive internal quantum efficiency (IQE) of 41 %, which represents the first benchmark for imidonitridophosphates and is promising for potential industrial application of this compound class.

9.
Front Mol Neurosci ; 17: 1397378, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39359690

RESUMO

In neurons, a diverse range of coding and non-coding RNAs localize to axons, dendrites, and synapses, where they facilitate rapid responses to local needs, such as axon and dendrite extension and branching, synapse formation, and synaptic plasticity. Here, we review the extent of our current understanding of RNA subclass diversity in these functionally demanding subcellular compartments. We discuss the similarities and differences identified between axonal, dendritic and synaptic local transcriptomes, and discuss the reported and hypothesized fates and functions of localized RNAs. Furthermore, we outline the RNA composition of exosomes that bud off from neurites, and their implications for the biology of neighboring cells. Finally, we highlight recent advances in third-generation sequencing technologies that will likely provide transformative insights into splice isoform and RNA modification diversity in local transcriptomes.

10.
Chemphyschem ; : e202400837, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39363694

RESUMO

Acetaldehyde (CH3CHO) plays a crucial role in the synthesis of prebiotic molecules such as amino acids, sugars, and sugar-related compounds, and in the progress of chain reaction polymerization in deep space. Here, we report the first formation of the cyclic acetaldehyde trimer - paraldehyde (C6H12O3) - in low-temperature interstellar analog ices exposed to energetic irradiation as proxies of galactic cosmic rays (GCRs). Utilizing vacuum ultraviolet photoionization reflectron time-of-flight mass spectrometry and isotopic substitution experiments, paraldehyde was identified in the gas phase during the temperature-programmed desorption of the irradiated acetaldehyde ices based on the calculated adiabatic ionization energies and isomer-specific dissociative fragmentation patterns upon photoionization. As acetaldehyde is ubiquitous throughout the interstellar medium and has been tentatively identified in interstellar ices, paraldehyde could have formed in acetaldehyde-containing ices in a cold molecular cloud and is an excellent candidate for gas-phase observation in star-forming regions via radio telescopes. The identification of paraldehyde in the gas phase from the processed acetaldehyde ices advances our understanding of how complex organic molecules can be synthesized through polymerization reactions in extraterrestrial ices exposed to GCRs.

11.
Cureus ; 16(10): e70768, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39364176

RESUMO

Non-alcoholic fatty liver disease (NAFLD), a metabolic condition, is becoming increasingly common in South Asia. While its clinical diagnosis primarily relies on sonography and altered hepatic biomarkers, the significance of non-hepatic indicators, such as Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), in relation to NAFLD requires further examination in the South Asian population due to ethnic differences in these markers. This study examined the relationship between insulin resistance, quantified using the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), and NAFLD, along with other non-hepatic biomarkers. A thorough literature review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched the PubMed, Embase, and Google Scholar databases, yielding 287 articles. After applying the selection criteria and screening, 22 studies were selected for inclusion in the analysis. We extracted and meta-analyzed the data on HOMA-IR in patients with NAFLD, along with other relevant parameters. The Newcastle-Ottawa Scale (NOS) was used to assess the quality of observational studies, whereas the RoB 2.0 tool was employed for randomized controlled trials (RCTs). The systematic review uncovered that individuals with NAFLD demonstrated statistically significant elevations in HOMA-IR levels, with a weighted mean difference (WMD) of 1.28 (95% confidence interval (CI): 1.00-1.58, I² = 98%, p < 0.0001) when compared to healthy subjects. Additionally, NAFLD patients showed markedly higher fasting blood glucose (FBG) levels, with a combined mean difference of 15.64 mg/dL (95% CI: 11.03-20.25, I² = 92%, p < 0.0001). The analysis also revealed increased triglyceride levels in NAFLD patients, with a pooled mean difference of 42.49 mg/dL (95% CI: 29.07-55.91, I² = 97%, p < 0.0001), and elevated C-reactive protein (CRP) levels, with a pooled mean difference of 2.17 mg/L (95% CI: 2.01-2.33, I² = 23%, p < 0.0001). Interestingly, subgroup analysis indicated that obese NAFLD patients exhibited significantly higher HOMA-IR levels than their non-obese counterparts, with a weighted mean difference of 5.85 (95% CI: 4.88-6.81, I² = 0%, p < 0.0001). Variations in study methodology, diagnostic techniques, and subject demographics were identified as sources of heterogeneity. The analysis found little evidence of publication bias, which lends credibility to the results. In South Asian populations, higher HOMA-IR, triglyceride-glucose (TyG) index, and CRP levels are associated with an increased risk of NAFLD. To improve the understanding and treatment of NAFLD in this specific demographic group, it is necessary to establish uniform diagnostic criteria and conduct additional studies, particularly RCTs.

12.
Appl Spectrosc ; : 37028241283050, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39370851

RESUMO

We have specified and obtained a ZnSe prism with an unconventional face angle cut to 30°. This prism, with internal incidence angles ranging from 30° to 48°, allows users to record internal reflection spectra below the critical angle and attenuated total reflection (ATR) spectra above the critical angle without the need to change optics or move or replace the sample. We demonstrate its capabilities using 102 spectra of benzyl benzoate taken with s- and p-polarization at different angles of incidence. The subcritical spectra were analyzed to obtain n∞, a key parameter for correcting the ATR spectra. These corrected spectra were subsequently used to determine the complex refractive index for all ATR measurements. The averaged complex refractive index function shows excellent agreement with that obtained through ATR spectroscopic ellipsometry.

13.
ACS Sens ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39350515

RESUMO

Transition metal oxide semiconductors have great potential for use in H2 sensors, but in recent years, the strange phenomena about gas-sensitive performance associated with their special properties have been more widely discussed in research. In some cases, the resistance of transition metal oxide gas sensors will emerge with some changes contrary to their intrinsic semiconductor characteristics, especially in gas sensor research of WO3. Based on the hydrothermal synthesis of WO3, our work focuses on the abnormal change of tungsten oxide resistance to different gases at low temperature (80-200 °C) and high temperature (above 200 °C). Through in situ FT-IR and in situ XPS, combined with density functional theory calculations, a new reasonable explanation of WO3 is proposed for the abnormal resistance change caused by temperature and the strange response due to gas concentration. The occurrence of these findings can be attributed to the synergistic effect resulting from the presence of two contributing factors. One of them is attributed to the alteration in the surface valence state of WO3 induced by gas, resulting in the reduction of W6+. The other one is due to the reaction between gas and adsorbed oxygen on the surface of WO3. This work presents a novel and rational concept for addressing the reaction mechanism between gas and transition metal oxide semiconductors, thereby paving the way for the development of highly efficient gas sensors based on transition metal oxide semiconductors.

14.
World J Microbiol Biotechnol ; 40(11): 336, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39358660

RESUMO

Soil and wastewater samples contaminated by petroleum-related industries were collected from various locations in Saudi Arabia, a country known for its vast oil reserves. The samples were analyzed for their physicochemical properties, including the presence of metals, petroleum hydrocarbons, and aromatic compounds. A total of 264 fungal isolates were analyzed and categorized into eight groups of Aspergillus (194 isolates) and four groups of Penicillium (70 isolates). The potential of these fungal groups to grow in oil or its derivatives was investigated. Two isolates, Aspergillus tubingensis FA-KSU5 and A. niger FU-KSU69, were utilized in two remediation experiments-one targeting wastewater and the other focusing on polluted soil. The FA-KSU5 strain demonstrated complete removal of Fe3+, As3+, Cr6+, Zn2+, Mn2+, Cu2+ and Cd2+, with bioremediation efficiency for petroleum hydrocarbons in the wastewater from these sites ranging between 90.80 and 98.58%. Additionally, the FU-KSU69 strain achieved up to 100% reduction of Co2+, Ba2+, B3+, V+, Ni2+, Pb2+ and Hg2+, with removal efficiency ranging from 93.17 to 96.02% for aromatic hydrocarbons after 180 min of wastewater treatment. After 21 days of soil incubation with Aspergillus tubingensis FA-KSU5, there was a 93.15% to 98.48% reduction in total petroleum hydrocarbons (TPHs) and an 88.11% to 97.31% decrease in polycyclic aromatic hydrocarbons (PAHs). This strain exhibited the highest removal rates for Cd2+ and As3+ followed by Fe3+, Zn2+, Cr6+, Se4+ and Cu2+. Aspergillus niger FU-KSU69 achieved a 90.37% to 94.90% reduction in TPHs and a 95.13% to 98.15% decrease in PAHs, with significant removal of Ni2+, Pb2+ and Hg2+, followed by Co2+, V+, Ba2+ and B3+. The enzymatic activity in the treated soils increased by 1.54- to 3.57-fold compared to the polluted soil. Although the mixture of wastewater and polluted soil exhibited high cytotoxicity against normal human cell lines, following mycoremediation, all treated soils and effluents with the dead fungal biomass showed no toxicity against normal human cell lines at concentrations up to 500 µL/mL, with IC50 values ≥ 1000 µL/mL. SEM and IR analysis revealed morphological and biochemical alterations in the biomass of A. tubingensis FA-KSU5 and A. niger FA-KSU69 when exposed to petroleum effluents. This study successfully introduces non-toxigenic and environmentally friendly fungal strains play a crucial role in the bioremediation of contaminated environments. Both strains serve as low-cost and effective adsorbents for bio-remediating petroleum wastewater and oil-contaminated soil. Heavy metals and hydrocarbons, the primary pollutants, were either completely removed or reduced to permissible levels according to international guidelines using the dead biomass of FA-KSU5 and FA-KSU69 fungi. Consequently, the environments associated with this globally significant industry are rendered biologically safe, particularly for humans, as evidenced by the absence of cytotoxicity in samples treated with A. tubingensis FA-KSU5 and A. niger FA-KSU69 on various human cell types.


Assuntos
Aspergillus , Biodegradação Ambiental , Petróleo , Microbiologia do Solo , Poluentes do Solo , Águas Residuárias , Águas Residuárias/microbiologia , Águas Residuárias/química , Petróleo/metabolismo , Poluentes do Solo/metabolismo , Aspergillus/metabolismo , Aspergillus/isolamento & purificação , Aspergillus/crescimento & desenvolvimento , Aspergillus/classificação , Penicillium/metabolismo , Penicillium/isolamento & purificação , Arábia Saudita , Poluição por Petróleo , Fungos/metabolismo , Fungos/classificação , Fungos/isolamento & purificação , Metais/metabolismo , Solo/química , Hidrocarbonetos/metabolismo
15.
Molecules ; 29(17)2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39274872

RESUMO

This work presents the results of studying dilute aqueous solutions of commercial Ln(NO3)3 · xH2O salts with Ln = Ce-Lu using X-ray diffraction (XRD), IR spectroscopy, X-ray absorption spectroscopy (XAS: EXAFS/XANES), and pH measurements. As a reference point, XRD and XAS measurements for characterized Ln(NO3)3 · xH2O microcrystalline powder samples were performed. The local structure of Ln-nitrate complexes in 20 mM Ln(NO3)3 · xH2O aqueous solution was studied under total external reflection conditions and EXAFS geometry was applied to obtain high-quality EXAFS data for solutions with low concentrations of Ln3+ ions. Results obtained by EXAFS spectroscopy showed significant contraction of the first coordination sphere during the dissolution process for metal ions located in the middle of the lanthanide series. It was established that in Ln(NO3)3 · xH2O solutions with Ln = Ce, Sm, Gd, Yb (c = 134, 100, 50 and 20 mM) there are coordinated and, to a greater extent, non-coordinated nitrate groups with bidentate and predominantly monodentate bonds with Ln ions, the number of which increases upon transition from cerium to ytterbium. For the first time, the antibacterial and antifungal activity of Ln(NO3)3 · xH2O Ln = Ce, Sm, Gd, Tb, Yb solutions with different concentrations and pH was presented. Cross-relationships between the concentration of solutions and antimicrobial activity with the type of Ln = Ce, Sm, Gd, Tb, Yb were established, as well as the absence of biocidal properties of solutions with a concentration of 20 mM, except for Ln = Yb. The important role of experimental conditions in obtaining and interpreting the results was noted.

16.
Molecules ; 29(17)2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39275099

RESUMO

Peptides are receiving significant attention in pharmaceutical sciences due to their applications as anti-inflammatory drugs; however, many aspects of their interactions and mechanisms at the molecular level are not well-known. This work explores the molecular structure of two peptides-(i) cysteine (Cys)-asparagine (Asn)-serine (Ser) (CNS) as a molecule in the gas phase and solvated in water in zwitterion form, and (ii) the crystal structure of the dipeptide serine-asparagine (SN), a reliable peptide indication whose experimental cell parameters are well known. A search was performed by means of atomistic calculations based on density functional theory (DFT). These calculations matched the experimental crystal structure of SN, validating the CNS results and useful for assignments of our experimental spectroscopic IR bands. Our calculations also explore the intercalation of CNS into the interlayer space of montmorillonite (MNT). Our quantum mechanical calculations show that the conformations of these peptides change significantly during intercalation into the confined interlayer space of MNT. This intercalation is energetically favorable, indicating that this process can be a useful preparation for therapeutic anti-inflammatory applications and showing high stability and controlled release processes.


Assuntos
Anti-Inflamatórios , Bentonita , Cisteína , Teoria da Densidade Funcional , Serina , Bentonita/química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Cisteína/química , Serina/química , Asparagina/química , Modelos Moleculares , Peptídeos/química , Substâncias Intercalantes/química
17.
Sensors (Basel) ; 24(17)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39275524

RESUMO

A THz-to-IR converter can be an effective solution for the detection of low-IR-signature targets by combining the advantages of mature IR detection mechanisms with high atmospheric transmittance in the THz region. A metallic metasurface (MS)-based absorber with linear polarization dependence based on a split-ring resonator (SRR) unit cell has been previously studied as a preliminary example of a THz-to-IR converter structure in the literature. In this simulation-based study, a new cross-shaped unit cell-based metallic MS absorber structure sensitive to dual polarization is designed to eliminate linear polarization dependency, thereby allowing for incoherent detection of THz radiation. A model is developed to calculate the temperature difference and the response time for this new cross-shaped absorber structure, and its performance is compared to the SRR structure for both coherent and incoherent illumination. This model allows for understanding the efficiency of these structures by considering all loss mechanisms which previously had not been considered. It is found that both structures show similar performance under linearly polarized coherent illumination. However, under incoherent illumination, the IR emittance efficiency as gauged by the temperature difference for the cross-shaped structure is found to be twice as high as compared to the SRR structure. The results also imply that calculated temperature differences for both structures under coherent and incoherent illumination are well above the limit of the minimum resolvable temperature difference of the state-of-the-art IR cameras. Therefore, dual-polarized or multi-polarization-sensitive MS absorber structures can be crucial for developing cost-effective THz-to-IR converters and be implemented in THz imaging solutions.

18.
Sci Justice ; 64(5): 477-484, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39277330

RESUMO

To determine whether a suspect was in close contact with the fire source at a fire site through slight thermal damage to hair, a cone calorimeter was employed to simulate fire scene conditions as a standard radiant source. The research focused on analyzing the thermal behavior of black hair and delving into the morphological characteristics of hair exhibiting slight thermal damage. At temperatures exceeding 240 °C, the proteins within the hair began to degrade. This degradation, in conjunction with tension along the hair shaft resulting from water loss, led to the formation of microcracks that could be detected through scanning electron microscopy (SEM) but eluded observation with an optical microscope (OM). It is noteworthy that the initial slight thermal damage was regularly located at the hair shaft but not the hair tip, which should be the key parts when exanimating hairs without obvious thermal damage. Additionally, during very short exposure, the appearance of typical slight thermal damage on fire is probabilistic events. Along with the increase of temperature, the organic compounds in hair were thermally degraded into NH3, SCO and carbon CO2, resulting in the typical traces of discoloration, expansion, blistering, and cracking presented at hair shafts and tips. The probability of encountering both slight and obvious thermal damage on hair increased with rising temperatures. By observing the traces on the easily overlooked part of the hair shaft, the research established a method to analyze and discriminate the slight thermal damage to hair at fire scene, which provide valuable references for confirming arson suspects.

19.
Ann Med Surg (Lond) ; 86(9): 5551-5556, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39239041

RESUMO

Introduction and importance: Near-infrared photoimmunotherapy (NIR-PIT, Alluminox) uses an antibody-photoabsorber conjugate and light excitation, requiring precise illumination. Mixed reality (MR) technology can enhance medical procedures through advanced visualization and planning. Case presentation: An 86-year-old man with recurrent oropharyngeal cancer and right cervical metastasis received NIR-PIT. Three-dimensional models from computed tomography (CT) and FDG-PET/CT images were used as holograms on a head-mounted display (HMD) for precise light targeting. Clinical discussion: HMD-MR technology was utilized for preoperative simulation and guided ideal light direction during surgery. This improved the effectiveness of NIR-PIT. Conclusion: Three months post-treatment, no residual lesion was observed, demonstrating the utility of HMD-MR technology in optimizing NIR-PIT outcomes.

20.
Front Endocrinol (Lausanne) ; 15: 1439326, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39247923

RESUMO

Background: The correlation between various insulin resistance surrogates and frailty remains under investigation in the scientific community. Methods: Data from NHANES (1999-2018) were used. We utilized weighted binary logistic regression, trend tests, RCS analysis, and subgroup analysis to comprehensively assess the link between METS-IR, HOMA-IR, and TyG, and frailty risk. Results: The results revealed a significant positive association between high levels of METS-IR, HOMA-IR, and TyG with the risk of frailty in all models. Notably, in model 4, the highest quintile of METS-IR showed the strongest link (OR: 2.960, 95% CI: 2.219-3.949), with HOMA-IR (OR: 2.522, 95% CI: 1.927-3.301) following closely behind. Trend tests revealed a positive trend between METS-IR, HOMA-IR, and TyG with the risk of frailty (P for trend < 0.05). RCS analysis showed a linear relationship between METS-IR and the risk of frailty (P for nonlinearity > 0.05). In contrast, HOMA-IR and TyG exhibited a U-shaped nonlinear relationship (P for nonlinearity < 0.05). Conclusion: The research identified a linear association between METS-IR and frailty risk, whereas HOMA-IR and TyG displayed a U-shaped, nonlinear relationship pattern with the risk of frailty. Among the varying levels examined, the linkage between METS-IR and frailty was most pronounced in the top quintile.


Assuntos
Fragilidade , Resistência à Insulina , Inquéritos Nutricionais , Humanos , Fragilidade/epidemiologia , Fragilidade/sangue , Feminino , Masculino , Estudos Transversais , Pessoa de Meia-Idade , Idoso , Adulto , Biomarcadores/sangue , Síndrome Metabólica/epidemiologia , Glicemia/análise , Glicemia/metabolismo , Estados Unidos/epidemiologia
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