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1.
bioRxiv ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38948740

RESUMO

Background: Hematopoietic transcription factor RUNX1 is expressed from proximal P2 and distal P1 promoter to yield isoforms RUNX1 B and C, respectively. The roles of these isoforms in RUNX1 autoregulation and downstream-gene regulation in megakaryocytes and platelets are unknown. Objectives: To understand the regulation of RUNX1 and its target genes by RUNX1 isoforms. Methods: We performed studies on RUNX1 isoforms in megakaryocytic HEL cells and HeLa cells (lack endogenous RUNX1), in platelets from 85 healthy volunteers administered aspirin or ticagrelor, and on the association of RUNX1 target genes with acute events in 587 patients with cardiovascular disease (CVD). Results: In chromatin immunoprecipitation and luciferase promoter assays, RUNX1 isoforms B and C bound and regulated P1 and P2 promoters. In HeLa cells RUNX1B decreased and RUNX1C increased P1 and P2 activities, respectively. In HEL cells, RUNX1B overexpression decreased RUNX1C and RUNX1A expression; RUNX1C increased RUNX1B and RUNX1A. RUNX1B and RUNX1C regulated target genes (MYL9, F13A1, PCTP, PDE5A and others) differentially in HEL cells. In platelets RUNX1B transcripts (by RNAseq) correlated negatively with RUNX1C and RUNX1A; RUNX1C correlated positively with RUNX1A. RUNX1B correlated positively with F13A1, PCTP, PDE5A, RAB1B, and others, and negatively with MYL9. In our previous studies, RUNX1C transcripts in whole blood were protective against acute events in CVD patients. We found that higher expression of RUNX1 targets F13A1 and RAB31 associated with acute events. Conclusions: RUNX1 isoforms B and C autoregulate RUNX1 and regulate downstream genes in a differential manner and this associates with acute events in CVD.

2.
J Opt Soc Am A Opt Image Sci Vis ; 41(6): 1059-1069, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856417

RESUMO

Optical skyrmions formed in terms of polarization are topological quasi-particles, and they have garnered much interest in the optical community owing to their unique inhomogeneous polarization structure and simplicity in their experimental realization. These structures belong to the Poincaré beams satisfying the stable topology. We theoretically investigated the non-diffracting and self-healing Poincaré beams based on the superposition of two orthogonal Bessel modes by the longitudinal mode matching technique. These Poincaré beams are topologically protected, and we suggest them as optical skyrmions in the corresponding Stokes vector fields. These optical skyrmions are quasi-skyrmions, and their range of propagation depends on the range of superposed Bessel modes. We have shown longitudinal mode matching of superposed Bessel beams is a necessary condition for the generation of propagation-invariant and non-diffracting skyrmions. The proposed longitudinal mode matching technique facilitates the generation of skyrmions with tunable position and range without any on-axis intensity modulations along the propagation axis. A suitable experimental configuration is suggested to realize variable order skyrmions in Bessel modes. The suggested experimental configuration can produce optical skyrmions even in ultra-short laser pulses with high mode conversion efficacy. This work can provide a new direction for the generation of skyrmions with completely new textures and features with reference to existing skyrmions originating from Laguerre-Gaussian modes.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124438, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-38901237

RESUMO

Barium lead alumino fluoroborate (BaPbAlFB) glasses singly and co-doped with Dy3+ and Eu3+ ions were prepared by melt quench method and studied their photoluminescence (PL) properties along with energy migration. Singly doped Dy3+/Eu3+ ions in BaPbAlFB glasses under 365 and 393 nm excitation wavelengths emit the PL bands through Dy: (4F9/2 → 6H15/2 and 4F9/2 → 6H13/2) and Eu: (5D0→7F2) transitions located at (Dy: 483 and 575 nm) and (Eu: 613 nm) respectively. Further, tunability of PL emissions is achieved by exciting the Dy3+/Eu3+ co-doped BaPbAlFB glasses at various wavelengths. The obtained CIE (0.34, 0.33) and CCT value (5080.4 K) of Dy3+/Eu3+ co-doped BaPbAlFB glass produced white light emission under 365 nm excitation wavelength. The corresponding CCT values of Dy3+/Eu3+ co-doped BaPbAlFB glasses varied from 1580 to 5080 K and their corresponding color emission changes from intense red to white light regime quite suitable for fabrication of epoxy-free w-LED devices.

4.
Front Vet Sci ; 11: 1376225, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881782

RESUMO

Hesperidin, a bioactive flavanone glycoside prevalent in citrus fruits, with remarkable therapeutic properties stands out as a formidable defender against the debilitating reproductive toxicity associated with Cyclophosphamide (CYP) chemotherapy. This study explores the protective potential of hesperidin (HSP@100 mg/kg b.wt PO daily) against CYP-induced (@ 40 mg/kg b.wt IP once in a week) reproductive toxicity in male Wistar rats as several studies were documented on single dose toxicity of CYP. In this experiment, we chose multidosage drug effects, which are more relevant in chemotherapy. Twenty-four rats were divided into four groups: Group 1 (Control), group 2 (CYP-treated), group 3 (HSP-treated), and group 4 (CYP + HSP-treated) for 28 days. The experimental design included assessments of relative testicular weight, semen analysis, testosterone levels, oxidative stress markers, inflammatory cytokines, gross and histopathological changes, and immunohistochemical evaluation. The results revealed that the administration of CYP led to a significant reduction in testicular weight, sperm count, motility, and testosterone levels, accompanied by increased oxidative stress and inflammatory response. Hesperidin co-administration demonstrated a protective effect by restoring these parameters to near-normal levels. Histopathological analysis revealed improved testicular architecture in the group 4 compared with the group 2. Oxidative stress indices indicated that hesperidin attenuated CYP-induced damage by reducing malondialdehyde levels, enhancing superoxide dismutase activity and maintaining glutathione levels. Similarly, inflammatory cytokine analysis demonstrated anti-inflammatory effects of hesperidin by reducing tumor necrosis factor-alpha (TNF-α) and elevating interleukin-10 (IL-10) levels in the group 4. Immunohistochemical evaluation of nuclear factor-kappa B (NF-κB) revealed increased inflammation in the CYP group, while hesperidin significantly reduced NF-κB expression, suggesting its anti-inflammatory properties.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38743212

RESUMO

PURPOSE: Nisin is a lantibiotic effective against Gram-positive microorganisms such as Streptococcus mutans. The study aimed to determine the effect of the addition of nisin to high-viscosity glass-ionomer cement (HVGIC) on its antibacterial activity, setting time, surface microhardness, and compressive strength. METHODS: 1 and 3% w/w nisin were added to HVGIC before mixing. Unmodified HVGIC was the control. Agar disc diffusion, direct contact test, and scanning electron microscopy (SEM) analysis were used to evaluate antibacterial activity against S. mutans. Setting time, surface microhardness, and compressive strength were measured using Gilmore needle apparatus, digital microhardness tester, and universal testing machine, respectively. Statistical analysis included Student's t test, one-way ANOVA with Tamhane's post hoc test, and repeated-measures ANOVA. RESULTS: As evidenced by the agar disc diffusion (p < 0.001), direct contact tests (p = 0.025), and SEM analysis of the S. mutans cell count and cell surface area (p = 0.049 and 0.003), 3% nisin had the strongest antibacterial activity. There was a dose-dependent increase in setting time (p = 0.005) and surface microhardness (p = 0.006), with no significant difference in compressive strength compared to control. CONCLUSION: The addition of 3% nisin to HVGIC enhances the antibacterial action against S. mutans and surface microhardness without adversely affecting setting time and compressive strength.

6.
Opt Express ; 32(6): 9011-9018, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571145

RESUMO

Multicolor visible high-order Bessel (Bessel-vortex) beams which have a helical wavefront and a long confocal length have garnered significant interest for applications in materials processing and biomedical technologies. In this paper, we demonstrate the direct generation of multicolor (523, 605 and 637 nm) Bessel-vortex beams from a Pr3+-doped water-proof fluoro-aluminate glass (Pr3+: WPFG) fiber laser with an intracavity lens which induces chromatic and spherical aberration. The handedness of the generated Bessel-vortex beam is selectively controlled through lateral displacement of the intra-cavity lens.

7.
JDR Clin Trans Res ; : 23800844231225193, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38389414

RESUMO

BACKGROUND: Parents often underuse dental care services for their children with early childhood caries (ECC), resulting in a high burden of untreated dental caries. AIM: To describe parental perceptions and challenges in dental care utilization for their children with ECC. DESIGN: A descriptive qualitative study was conducted with parents of children with ECC seeking dental care in Mangalore, India. Data were collected through focus group discussions using an interview guide. Manual line-by-line coding and content analysis methods were used for data analysis. RESULTS: Three categories were generated from data obtained through 5 focus groups of 27 participants: dental care visiting patterns, the significance of dental visits, and challenges to dental care utilization. Parents would only visit the dentist when they perceived their children's tooth problems. The challenges faced include time constraints, misinformation, lack of awareness and motivation, costs, fear, and anxiety of the children and the parents themselves. Parents perceived improvements in the awareness of their children's oral health and quality of life after dental visits. CONCLUSION: Attending dental services to treat their children's tooth problems was the primary way of attaining awareness about prevention among the parents of children with ECC. Increased oral health awareness and improved quality of life can motivate parents to seek further dental care for their children. Collaboration with multidisciplinary stakeholders is required to improve oral health awareness among parents of children with ECC. KNOWLEDGE TRANSFER STATEMENT: The study's results will help plan targeted preventive programs for children with ECC. The study suggests dental care utilization by children with ECC is based on parental perceptions of their children's tooth problems. It outlines the challenges that affect dental visits of children with ECC and the role of multidisciplinary stakeholders. Improved oral health awareness and quality of life following dental treatment can facilitate further dental visits.

8.
Blood Adv ; 8(7): 1699-1714, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38330198

RESUMO

ABSTRACT: Platelet α-granules have numerous proteins, some synthesized by megakaryocytes (MK) and others not synthesized but incorporated by endocytosis, an incompletely understood process in platelets/MK. Germ line RUNX1 haplodeficiency, referred to as familial platelet defect with predisposition to myeloid malignancies (FPDMMs), is associated with thrombocytopenia, platelet dysfunction, and granule deficiencies. In previous studies, we found that platelet albumin, fibrinogen, and immunoglobulin G (IgG) were decreased in a patient with FPDMM. We now show that platelet endocytosis of fluorescent-labeled albumin, fibrinogen, and IgG is decreased in the patient and his daughter with FPDMM. In megakaryocytic human erythroleukemia (HEL) cells, small interfering RNA RUNX1 knockdown (KD) increased uptake of these proteins over 24 hours compared with control cells, with increases in caveolin-1 and flotillin-1 (2 independent regulators of clathrin-independent endocytosis), LAMP2 (a lysosomal marker), RAB11 (a marker of recycling endosomes), and IFITM3. Caveolin-1 downregulation in RUNX1-deficient HEL cells abrogated the increased uptake of albumin, but not fibrinogen. Albumin, but not fibrinogen, partially colocalized with caveolin-1. RUNX1 KD resulted in increased colocalization of albumin with flotillin and fibrinogen with RAB11, suggesting altered trafficking of both proteins. The increased uptake of albumin and fibrinogen, as well as levels of caveolin-1, flotillin-1, LAMP2, and IFITM3, were recapitulated by short hairpin RNA RUNX1 KD in CD34+-derived MK. To our knowledge, these studies provide first evidence that platelet endocytosis of albumin and fibrinogen is impaired in some patients with RUNX1-haplodeficiency and suggest that megakaryocytes have enhanced endocytosis with defective trafficking, leading to loss of these proteins by distinct mechanisms. This study provides new insights into mechanisms governing endocytosis and α-granule deficiencies in RUNX1-haplodeficiency.


Assuntos
Transtornos Herdados da Coagulação Sanguínea , Transtornos Plaquetários , Hemostáticos , Leucemia Eritroblástica Aguda , Leucemia Mieloide Aguda , Humanos , Megacariócitos/metabolismo , Caveolina 1/metabolismo , Fibrinogênio/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Endocitose , Albuminas/metabolismo , Imunoglobulina G , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/metabolismo
9.
Anal Methods ; 16(6): 950-956, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38291911

RESUMO

Proteins play an important role in biological systems and several proteins are used in diagnosis, therapy, food industry etc. Thus, knowledge about the physical properties of the proteins is of utmost importance, which will aid in understanding their function and subsequent applications. The melting temperature (Tm) of a protein is one of the essential parameters which gives information about the stability of a protein under different conditions. In the present study, we have demonstrated a method for determining the Tm of proteins using the supramolecular interaction between Quinaldine Red (QR) and proteins. Using this method, we have determined the Tm of 5 proteins and compared our results with established protocols. Our results showed good agreement with the other methods and published values. The method developed in this study is inexpensive, quick, and devoid of complex instruments and pre/post-treatment of the samples. In addition, this method can be adopted for high throughput in multi-plate mode. Thus, this study projects a new methodology for Tm determination of various proteins with user friendly operation.


Assuntos
Corantes Fluorescentes , Quinaldinas , Temperatura , Proteínas
10.
Clin Oncol (R Coll Radiol) ; 36(1): e61-e71, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37953073

RESUMO

AIMS: Global guidelines recommend that all older patients with cancer receiving chemotherapy should undergo a geriatric assessment. However, utilisation of the geriatric assessment is often constrained by its time-intensive nature, which limits its adoption in settings with limited resources and high demand. There is a lack of evidence correlating the results of the geriatric assessment with survival from the Indian subcontinent. Therefore, the aims of the present study were to assess the impact of the geriatric assessment on survival in older Indian patients with cancer and to identify the factors associated with survival in these older patients. MATERIALS AND METHODS: This was an observational study, conducted in the geriatric oncology clinic of the Tata Memorial Hospital (Mumbai, India). Patients aged 60 years and older with cancer who underwent a geriatric assessment were enrolled. We assessed the non-oncological geriatric domains of function and falls, nutrition, comorbidities, cognition, psychology, social support and medications. Patients exhibiting impairment in two or more domains were classified as frail. RESULTS: Between June 2018 and January 2022, we enrolled 897 patients. The median age was 69 (interquartile range 65-73) years. The common malignancies were lung (40.5%), oesophagus (31.9%) and genitourinary (12.1%); 54.6% had metastatic disease. Based on the results of the geriatric assessment, 767 (85.4%) patients were frail. The estimated median overall survival in fit patients was 24.3 (95% confidence interval 18.2-not reached) months, compared with 11.2 (10.1-12.8) months in frail patients (hazard ratio 0.54; 95% confidence interval 0.41-0.72, P < 0.001). This difference in overall survival remained significant after adjusting for age, sex, primary tumour and metastatic status (hazard ratio 0.56; 95% confidence interval 0.41-0.74, P < 0.001). In the patients with a performance status of 0 or 1 (n = 454), 365 (80.4%) were frail; the median overall survival in the performance status 0-1 group was 33.0 months (95% confidence interval 24.31-not reached) in the fit group versus 14.4 months (95% confidence interval 12.25-18.73) in the frail patients (hazard ratio 0.50; 95% confidence interval 0.34-0.74, P = 0.001). In the multivariate analysis, the geriatric assessment domains that were predictive of survival were function (hazard ratio 0.68; 95% confidence interval 0.52-0.88; P = 0.003), nutrition (hazard ratio 0.64; 95% confidence interval 0.48-0.85, P = 0.002) and cognition (hazard ratio 0.67; 95% confidence interval 0.49-0.91, P = 0.011). DISCUSSION: The geriatric assessment is a powerful prognostic tool for survival among older Indian patients with cancer. The geriatric assessment is prognostic even in the cohort of patients thought to be the fittest, i.e. performance status 0 and 1. Our study re-emphasises the critical importance of the geriatric assessment in all older patients planned for cancer-directed therapy.


Assuntos
Avaliação Geriátrica , Neoplasias , Idoso , Humanos , Pessoa de Meia-Idade , Avaliação Geriátrica/métodos , Neoplasias/tratamento farmacológico , Prognóstico , Modelos de Riscos Proporcionais , Comorbidade
11.
Traffic Inj Prev ; 25(1): 49-56, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37815797

RESUMO

OBJECTIVES: Driving is a dynamic activity that takes place in a constantly changing environment, carrying safety implications not only for the driver but also for other road users. Despite the potentially life-threatening consequences of incorrect driving behavior, drivers often engage in activities unrelated to driving. This study aims to investigate the frequency and types of errors committed by drivers when they are distracted compared to when they are not distracted. METHODS: A total of 64 young male participants volunteered for the study, completing four driving trials in a driving simulator. The trials consisted of different distraction conditions: listening to researcher-selected music, driver-selected music, FM radio conversation, and driving without any auditory distractions. The simulated driving scenario resembled a semi-urban environment, with a track length of 12 km. RESULTS: The findings of the study indicate that drivers are more prone to making errors when engaged in FM radio conversations compared to listening to music. Additionally, errors related to speeding were found to be more prevalent across all experimental conditions. CONCLUSIONS: These results emphasize the significance of reducing distractions while driving to improve road safety. The findings add to our understanding of the particular distractions that carry higher risks and underscore the necessity for focused interventions to reduce driver errors, especially related to FM radio conversations. Future research can delve into additional factors that contribute to driving errors and develop effective strategies to promote safer driving practices.


Assuntos
Condução de Veículo , Direção Distraída , Música , Humanos , Masculino , Acidentes de Trânsito/prevenção & controle , Atenção , Comunicação
12.
J Fluoresc ; 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38157084

RESUMO

Dysprosium oxide-doped glasses with a composition of 60B2O3-10Sb2O3-10Al2O3-10NaF-(10-x) LiF-xDy2O3 (x = 0.1,0.5, 1.0,1.5,2.0,2.5 mol%) were prepared using a conventional melt-quenching technique. The glasses were characterized through various analytical investigations, including X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, refractive index, density, optical absorption, excitation, photoluminescence (PL) studies, decay measurements and radiation shielding parameters. The XRD and FT-IR confirms the glassy nature and functional groups present in the titled glass. The absorption spectra were used to determine the oscillator strength of the Dy3+ absorption transitions as well as the bond created with the O-2 ion in the titled glass network. The degree of the suitability of developed glasses for lasing applications was demonstrated by radiative parameters determined using Judd-Ofelt theory. In the prepared glass samples, the optical bandgap measurements indicate the presence of non-bridging oxygen (NBOs), localization of charges and donor centers in the titled glasses. Due to the de-excitation of 4F9/2 to the corresponding 6H15/2,6H13/2 and 6H11/2 states, the PL emission spectrum shows two main strong emissions at blue(480nm), yellow (575nm) and one less emission at red (663nm). The CIE coordinates determined using PL emission spectra reveal the coordinates that are falling within the white light region. Various shielding parameters such as mass attenuation coefficient, mean free path, effective atomic number were estimated to understand the radiative shielding nature of the titled glasses. Within the addition of Dy2O3, it was found that the shielding parameters values of the titled glass samples are increasing. The Mass Attenuation Coefficient, Half Value Layer and Mean Free Path of the as prepared glasses has been compared with different types of concretes to understand the shielding effectiveness of prepared glass.

13.
Appl Opt ; 62(34): 9183-9187, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38108757

RESUMO

We report the direct generation of vector vortex laser modes at 640 nm from a compact, diode end-pumped continuous-wave P r 3+:L i Y F 4 (YLF) laser that utilizes an intracavity lens and diaphragm. On-axis displacement of the intracavity lens, combined with appropriate choice of the intracavity diaphragm, enables selective generation of a desired radial and azimuthal vector laser mode. Such compact, vector vortex laser sources based on P r 3+:Y L F in the visible wavelength region are a significant enabling technology for a wide range of applications.

14.
medRxiv ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37961544

RESUMO

Platelet α-granules have numerous proteins, some synthesized by megakaryocytes (MK) and others not synthesized but incorporated by endocytosis, an incompletely understood process in platelets/MK. Germline RUNX1 haplodeficiency, referred to as familial platelet defect with predisposition to myeloid malignancies (FPDMM), is associated with thrombocytopenia, platelet dysfunction and granule deficiencies. In previous studies, we found that platelet albumin, fibrinogen and IgG levels were decreased in a FPDMM patient. We now show that platelet endocytosis of fluorescent-labeled albumin, fibrinogen and IgG is decreased in the patient and his daughter with FPDMM. In megakaryocytic human erythroleukemia (HEL) cells, siRNA RUNX1 knockdown (KD) increased uptake of these proteins over 24 hours compared to control cells, with increases in caveolin-1 and flotillin-1 (two independent regulators of clathrin-independent endocytosis), LAMP2 (a lysosomal marker), RAB11 (a marker of recycling endosomes) and IFITM3. Caveolin-1 downregulation in RUNX1-deficient HEL cells abrogated the increased uptake of albumin, but not fibrinogen. Albumin, but not fibrinogen, partially colocalized with caveolin-1. RUNX1 knockdown increased colocalization of albumin with flotillin and of fibrinogen with RAB11 suggesting altered trafficking of both. The increased albumin and fibrinogen uptake and levels of caveolin-1, flotillin-1, LAMP2 and IFITM3 were recapitulated by shRNA RUNX1 knockdown in CD34 + -derived MK. These studies provide the first evidence that in RUNX1- haplodeficiency platelet endocytosis of albumin and fibrinogen is impaired and that megakaryocytes have enhanced endocytosis with defective trafficking leading to loss of these proteins by distinct mechanisms. They provide new insights into mechanisms governing endocytosis and α-granule deficiencies in RUNX1- haplodeficiency. Key points: Platelet content and endocytosis of α-granule proteins, albumin, fibrinogen and IgG, are decreased in germline RUNX1 haplodeficiency. In RUNX1 -deficient HEL cells and primary MK endocytosis is enhanced with defective trafficking leading to decreased protein levels.

15.
RSC Adv ; 13(48): 33675-33687, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38020000

RESUMO

This paper investigates the synthesis and luminescence characteristics of Tm3+/Tb3+/Eu3+ co-doped Sr4Nb2O9 (SNB) phosphors as potential candidates for white light-emitting diodes (WLEDs). The study explores the energy transfer mechanisms and color-tunable characteristics of these phosphors. The SNB phosphors were prepared using a solid-state reaction method, and their structural and morphological properties were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared (FT-IR) spectroscopy. The diffuse reflectance, photoluminescence (PL) and time resolved photoluminescence (TRPL) properties were investigated, revealing efficient energy transfer processes from Tm3+ to Tb3+ and Eu3+ ions. The energy transfer mechanisms were determined through critical distance calculations and analysis of multipolar interactions. The co-doped phosphors exhibited tunable emission colors ranging from blue to white light, with controllable correlated color temperatures (CCTs) and high color rendering indices (CRIs). The CIE chromaticity coordinates were optimized to approach neutral white light. The PL intensity is maintained at 81.19% at 150 °C of that of room temperature which showcases the remarkable thermal stability of the as-prepared phosphors. The results highlight the potential of Tm3+/Tb3+/Eu3+ co-doped SNB phosphors for generating high-quality, color-tunable white light for advanced lighting applications.

16.
J Fluoresc ; 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37804477

RESUMO

In the current study, Sm3+ ions doped Lithium Barium Tungstate (Li2Ba5W3O15) (LBW) phosphors with the ability to emit orange-red light were made using the traditional high-temperature solid-state reaction technique. The structure and phase of the as-synthesized phosphor samples were examined via X-ray diffraction (XRD) patterns. The diffraction peaks of the undoped LBW and Sm3+ ions doped LBW phosphors closely resemble those of the Joint Committee on Powder Diffraction Standards (JCPDS) pattern with card number 01-072-1717. Scanning electron microscopy (SEM) was employed for the analysis of the morphological characteristics of the synthesized phosphor material. Fourier Transform Infrared (FT-IR) spectroscopy was used to study several vibrational and molecular bands present in the host matrix. Using diffuse reflectance spectra (DRS), the optical band gap values (Eg) were evaluated by applying Tauc's method. The photoluminescence (PL) spectra characteristics at λex = 336 nm indicate the emission of dopant ions (Sm3+) in the deep orange-red region corresponding to 4G5/2 → 6H5/2 transition (at 581 nm) with concentration quenching after 2 mol % of Sm3+ ions. Using the PL spectra, the CIE chromaticity coordinates of LBWS2.0 phosphor were estimated and found in the deep visible orange-red area, indicating the potential use of the prepared phosphor material for phosphor-converted white light emitting diodes (w-LEDs) applications. Double exponential behaviour can be seen in the PL decay spectral profiles obtained under λem = 581 nm and λex = 336 nm. The experimental lifetimes (τexp) decrease as the concentration of Sm3+ ions rise. The temperature-dependent PL (TDPL) and activation energy results show that the as-synthesized phosphor has considerably superior thermal stability. The results of the current research contemplate us the applicability of Sm3+ ions doped LBW phosphor for photonic devices such as w-LEDs.

17.
Int J Biol Macromol ; 253(Pt 4): 127013, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37734517

RESUMO

Crosslinked hydrophilic polymers with high water absorption rates are known as superabsorbent polymers (SAPs). Most commercial superabsorbent polymers are made with acrylic acid, which is difficult to biodegrade. So, in this investigation, carboxymethyl cellulose (CMC) was utilized as a significant component in the synthesis of polysaccharide-based SAPs. Citric acid (CA) and starch were chosen as crosslinking agents because they are more eco-friendly, non-toxic, and biodegradable than traditional crosslinking agents. FTIR analysis revealed that the superabsorbent polymer product contains a crosslinked structure of CMC and starch with side chains that carry carboxylate functional groups. Superabsorbent weight loss and grafting data were satisfactorily studied using the TGA approach. Under optimum circumstances, the SAP2 water absorbency capacity in distilled water was 287.37 g.g-1 and SAP1 absorbency capacity in a solution containing 0.9 wt% NaCl was 52.18 g.g-1. Moreover, Schott's pseudo-second-order model was used to determine the kinetic swelling of the superabsorbent. The initial swelling rate of SAPs can be calculated using the Q∞ data acquired in the following order: SAP2 > SAP1 > SAP3 > SAP4 in distilled water and SAP1 > SAP2 > SAP3 > SAP4 in 0.9 wt% NaCl solution, respectively. The findings suggested that a small amount of citric acid introduced into the SAPs matrix could enhance the swelling rate of SAPs. The results of the cytotoxicity tests show that the extraction liquid of composite hydrogel fibers is less cytotoxic than the positive control. As well, SAP underwent in silico docking investigations on the DNA Gyrase enzyme. As the ligand is a monomer of SAP, it was a long chain of carbohydrate molecules with alcoholic groups, esters groups, and keto groups forms a strong binding interaction with DNA gyrase.


Assuntos
Carboximetilcelulose Sódica , Polímeros , Polímeros/química , Carboximetilcelulose Sódica/química , Cloreto de Sódio/química , Sódio , Amido/química , DNA Girase , Água/química
18.
Nat Chem ; 15(11): 1503-1508, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37640849

RESUMO

Conical intersections are ubiquitous in chemistry and physics, often governing processes such as light harvesting, vision, photocatalysis and chemical reactivity. They act as funnels between electronic states of molecules, allowing rapid and efficient relaxation during chemical dynamics. In addition, when a reaction path encircles a conical intersection, the molecular wavefunction experiences a geometric phase, which can affect the outcome of the reaction through quantum-mechanical interference. Past experiments have measured indirect signatures of geometric phases in scattering patterns and spectroscopic observables, but there has been no direct observation of the underlying wavepacket interference. Here we experimentally observe geometric-phase interference in the dynamics of a wavepacket travelling around an engineered conical intersection in a programmable trapped-ion quantum simulator. To achieve this, we develop a technique to reconstruct the two-dimensional wavepacket densities of a trapped ion. Experiments agree with the theoretical model, demonstrating the ability of analogue quantum simulators-such as those realized using trapped ions-to accurately describe nuclear quantum effects.

19.
ArXiv ; 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37396598

RESUMO

Attention Deficit Hyperactive Disorder (ADHD) is a common behavioral problem affecting children. In this work, we investigate the automatic classification of ADHD subjects using the resting state Functional Magnetic Resonance Imaging (fMRI) sequences of the brain. We show that the brain can be modeled as a functional network, and certain properties of the networks differ in ADHD subjects from control subjects. We compute the pairwise correlation of brain voxels' activity over the time frame of the experimental protocol which helps to model the function of a brain as a network. Different network features are computed for each of the voxels constructing the network. The concatenation of the network features of all the voxels in a brain serves as the feature vector. Feature vectors from a set of subjects are then used to train a PCA-LDA (principal component analysis-linear discriminant analysis) based classifier. We hypothesized that ADHD-related differences lie in some specific regions of the brain and using features only from those regions is sufficient to discriminate ADHD and control subjects. We propose a method to create a brain mask that includes the useful regions only and demonstrate that using the feature from the masked regions improves classification accuracy on the test data set. We train our classifier with 776 subjects and test on 171 subjects provided by The Neuro Bureau for the ADHD-200 challenge. We demonstrate the utility of graph-motif features, specifically the maps that represent the frequency of participation of voxels in network cycles of length 3. The best classification performance (69.59%) is achieved using 3-cycle map features with masking. Our proposed approach holds promise in being able to diagnose and understand the disorder.

20.
Chemosphere ; 337: 139336, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37379991

RESUMO

One of the environmental pollution is happened by the discharge of industrial wastewater that needs to be adequately filtered. Given that the effluent from the leather industry contains high levels of chromium, heavy metals, lipids, and Sulphur, it is one of the wastewater disposals that are most damaging. This experimental study focuses on reverse osmosis and hybrid organic polyimide membrane for nanofiltration for sustainable wastewater treatment. In the RO and organic polyamide Nano-porous membranes, a thin film of polyamide membrane was used for efficient filtration. Taguchi analysis optimized process parameters such as pressure, temperature, pH, and volume reduction factor. The outcome shows an 89% reduction in total wastewater hardness, an 88% reduction in sulfate, and an 89% efficiency reduction in COD. As a result, the proposed technology significantly increased filtration efficiency.


Assuntos
Águas Residuárias , Purificação da Água , Nylons , Osmose , Membranas Artificiais , Filtração , Eliminação de Resíduos Líquidos
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