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BACKGROUND: Programmed death receptor ligand 1 (PD-L1) tumor proportion score (TPS) and tumor mutational burden (TMB) are key predictive biomarkers for immune checkpoint inhibitor (ICI) efficacy in non-small-cell lung cancer (NSCLC). Data on their variation across multiple samples are limited. PATIENTS AND METHODS: Patients with NSCLC and multiple PD-L1 TPS and/or TMB assessments were included. Clinicopathologic and genomic data were analyzed according to PD-L1 and TMB variation. RESULTS: In total, 402 PD-L1 sample pairs and 413 TMB sample pairs were included. Concordance between pairs was moderate for PD-L1 (ρ = 0.53, P < 0.0001) and high for TMB (ρ = 0.80, P < 0.0001). Shorter time between biopsies correlated with higher concordance in PD-L1, but not in TMB. Major increases (ΔTPS ≥ +50%) and decreases (ΔTPS ≤ -50%) in PD-L1 were observed in 9.7% and 8.0% of cases, respectively. PD-L1, but not TMB, decreased with intervening ICI (P = 0.02). Acquired copy number loss of CD274, PDCD1LG2, and JAK2 were associated with major decrease in PD-L1 (q < 0.05). Among patients with multiple PD-L1 assessments before ICI, cases where all samples had a PD-L1 ≥1%, compared to cases with at least one sample with PD-L1 <1% and another with PD-L1 ≥1%, achieved improved objective response rate and progression-free survival (PFS). Among patients with at least one PD-L1 <1% and one ≥1% before ICI, cases where the most proximal sample was PD-L1 ≥1% had longer median PFS compared to cases where the most proximal PD-L1 was <1%. Among patients with multiple TMB assessments before ICI, patients with a TMB ≥10 mut/Mb based on the most recent assessment, as compared to those with a TMB <10 mut/Mb, achieved improved PFS and overall survival to ICI; instead, no differences were observed when patients were categorized using the oldest TMB assessment. CONCLUSIONS: Despite intrapatient concordance in PD-L1 and TMB, variation in these biomarkers can influence ICI outcomes, warranting consideration for reassessment before ICI initiation when feasible.
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The aim of the present work is to biosynthesize Chitosan nanoparticles (CTNp) using tea (Camellia sinensis) extract, with potent antimicrobial properties towards phytopathogens of rice. Preliminary chemical analysis of the extract showed that they contain carbohydrate as major compound and uronic acid indicating the nature of acidic polysaccharide. The structure of the isolated polysaccharide was analyzed through FTIR and 1H NMR. The CTNp was prepared by the addition of isolated tea polysaccharides to chitosan solution. The structure and size of the CTNp was determined through FTIR and DLS analyses. The surface morphology and size of the CTNp was analysed by SEM and HRTEM. The crystalinity nature of the synthesized nanoparticle was identified by XRD analysis. The CTNp exhibited the antimicrobial properties against the most devastating pathogens of rice viz., Pyricularia grisea, Xanthomonas oryzae under in vitro condition. CTNp also suppressed the blast and blight disease of rice under the detached leaf assay. These results suggest that the biosynthesized CTNp can be used to control the most devastating pathogens of rice.
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Quitosano , Nanopartículas , Oryza , Quitosano/farmacología , Nanopartículas/química , Té , Extractos Vegetales/farmacologíaRESUMEN
Mpox, previously known as monkeypox, is caused by an Orthopoxvirus related to the variola virus that causes smallpox. Prior to 2022, mpox was considered a zoonotic disease endemic to central and west Africa. Since May 2022, more than 86,000 cases of mpox from 110 countries have been identified across the world, predominantly in men who have sex with men, most often acquired through close physical contact or during sexual activity. The classical clinical presentation of mpox is a prodrome including fever, lethargy, and lymphadenopathy followed by a characteristic vesiculopustular rash. The recent 2022 outbreak included novel presentations of mpox with a predominance of anogenital lesions, mucosal lesions, and other features such as anorectal pain, proctitis, oropharyngeal lesions, tonsillitis, and multiphasic skin lesions. We describe the demographics and clinical spectrum of classical and novel mpox, outlining the potential complications and management.
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Mpox , Minorías Sexuales y de Género , Masculino , Animales , Humanos , Homosexualidad Masculina , Zoonosis , Brotes de EnfermedadesRESUMEN
There is conflicting evidence regarding the association between epidural labour analgesia and risk of postpartum depression. Most previous studies were observational trials with limited ability to account for confounders. We aimed to determine if epidural analgesia was associated with a significant change in the incidence of postpartum depression in this randomised controlled trial. We enrolled women aged 21-50 years old with a singleton fetus ≥ 36 weeks gestation. Patients were advised regarding available labour analgesic modalities during enrolment (epidural block; intramuscular pethidine; nitrous oxide; or intravenous remifentanil). On request for analgesia, patients were offered the modality that they had been allocated randomly to first. Blinded investigators recorded patient and obstetric characteristics within 24 h of delivery and assessed for postpartum depression at 6-10 weeks following delivery using the Edinburgh Postnatal Depression Scale (score ≥ 13 considered positive for postpartum depression). The modified intention-to-treat population consisted of all patients who received any form of labour analgesia, while per-protocol consisted of patients who received their randomised modality as their first form of labour analgesia. Of 881 parturients allocated randomly (epidural n = 441, non-epidural n = 440), we analysed 773 (epidural n = 389, non-epidural n = 384); 62 (15.9%) of women allocated to epidural group developed postpartum depression compared with 65 (16.9%) women allocate to the non-epidural group. There were no significant differences in the incidence of postpartum depression between the two groups (adjusted risk difference (95%CI) 1.6 (-3.0-6.3%), p = 0.49). Similar results were obtained with per-protocol analysis (adjusted risk difference (95%CI) -1.0 (-8.3-6.3%), p = 0.79). We found no significant difference in the risk of postpartum depression between patients who received epidural labour analgesia and those who utilised non-epidural analgesic modalities.
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Analgesia Epidural , Analgesia Obstétrica , Depresión Posparto , Dolor de Parto , Trabajo de Parto , Embarazo , Humanos , Femenino , Adulto Joven , Adulto , Persona de Mediana Edad , Masculino , Analgesia Epidural/efectos adversos , Analgesia Epidural/métodos , Depresión Posparto/epidemiología , Analgésicos , Analgesia Obstétrica/efectos adversos , Analgesia Obstétrica/métodosRESUMEN
In order to reduce contamination levels from diverse sources, it is important to understand the factors affecting the natural ecosystems that are impacted by coastal and marine pollution. In this study, we used GIS and remote sensing techniques to investigate and evaluate the distribution of heavy metals (Fe, Mn, Zn, Cr, Pb, Co, and Cu) in surface sediments along Tamil Nadu's East Coast (from Besant Nagar to Sathurangapattinam). The CF and Igeo of metals indicate that sediments contain no evidence of Fe, Mn, or Zn metal pollution in the sediments, with only mild contamination from Co, Cu, and Pb. In contrast, the sediment samples were found to be significantly contaminated with Cr. Heavy metal contamination occurs in the following order, according to our research: Cr > Pb > Cu > Co > Mn > Zn > Fe. Except for sites 8, 10, 11, and 13, where PLI>1 implies that there is no pollution in this area, the PLI values show that most of the locations are contaminated. The ecological risk index (ERI) values for five metals in the study areas are as follows: Cr > Pb > Cu > Mn > Zn. The sediment samples fall into the low-risk and highly polluted to dangerous sediment categories for SPI, according to the Risk index (RI). Based on the Mean Effect Range-Median Quotient (M-ERM-Q), Cu, Pb, Zn, and Cr metals in the research region have a 9-21% probability of being harmful. Statistical approaches show that the majority of heavy metals in sediments are of natural origin. The spatial distribution of heavy metals in surface sediments provides the conceptual framework for practical strategies to protect coastal areas. Many shreds of evidence indicate that anthropogenic inputs from the surrounding land area are primarily responsible for the deposition of these heavy metals in the coastal zone.
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Metales Pesados , Contaminantes Químicos del Agua , Ecosistema , India , Plomo , Sedimentos Geológicos , Contaminantes Químicos del Agua/análisis , Medición de Riesgo , Monitoreo del Ambiente/métodos , Metales Pesados/análisisRESUMEN
OBJECTIVE: Previous small studies used individualized growth assessment (IGA) to characterize prenatal growth velocities of singletons and twins. We aimed to compare second-trimester growth velocities of individual anatomical parameters between monochorionic diamniotic (MCDA) twins, dichorionic diamniotic (DCDA) twins and singleton fetuses in a larger study. METHODS: This was a study of a novel cohort of 222 MCDA twins and previously published cohorts of 40 DCDA twins and 118 singletons with serial ultrasound data. Fetal biometric measurements of biparietal diameter, head circumference, abdominal circumference and femur diaphysis length from prenatal ultrasound examinations were used to calculate second-trimester growth velocities using direct calculation or linear regression analysis. Linear fit was assessed based on the coefficient of determination (R2 ). Mean growth velocities and variances were compared among the three groups. RESULTS: The majority of cases underwent three second-trimester ultrasound examinations with fetal biometry available. All fetuses had linear growth, with R2 > 99% for all parameters. Only 1-2% of all MCDA and DCDA anatomical parameters had abnormal growth velocity scores outside the 95% reference range for singletons. There were no significant differences in mean growth velocity for any parameter between MCDA twins and singletons. Femur diaphysis length growth velocity was significantly lower in DCDA twins than in both MCDA twins and singletons. There were no other significant differences among the groups. CONCLUSIONS: Expanding on prior work using IGA, we found that second-trimester growth velocity of the four major anatomical parameters overall was similar between twins and singletons and between MCDA and DCDA twins, supporting the use of singleton-derived growth standards for IGA in twins. Twin growth potential appears to be similar to that of singletons in the second trimester, suggesting that subsequent growth divergence may be due to third-trimester physiological or pathological changes in twin pregnancies. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.
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Embarazo Gemelar , Gemelos Dicigóticos , Embarazo , Femenino , Humanos , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Ultrasonografía Prenatal , Inmunoglobulina A , Estudios Retrospectivos , Gemelos MonocigóticosRESUMEN
The present study evaluated the effect of thiamine loaded chitosan nanoparticle (TChNp) on chickpea plant growth under greenhouse condition. TChNp treated plants showed increased number of leaves, branches, shoot/root length, number of secondary roots and plant dry weight. Enhanced nodulation with larger nodules was observed in TChNp treated chickpea plants. A significant increase in the number of flowers, pods and grain yield was observed in the TChNp treated chickpea plants compared to the chitosan and untreated control. The TChNps showed direct antifungal activity towards Rhizoctonia bataticola as evidenced by in vitro and SEM analyses, which might be due to the solubility and size of the nanoparticle. TChNps treated chickpea plants challenged with R. bataticola showed significant reduction in plant mortality compared to infected untreated control under pot condition. These results indicate the potential of the TChNps in enhancing the yield and suppressing the dry root rot disease in chickpea.
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Quitosano , Cicer , Nanopartículas , TiaminaRESUMEN
BACKGROUND: Direct-acting antivirals (DAAs) are highly effective in achieving sustained virologic response among those with chronic hepatitis C virus (HCV) infection. Quality of life (QOL) benefits for an HCV-infected population with high numbers of people who inject drugs and people living with HIV (PLHIV) in Eastern Europe have not been explored. We estimated such benefits for Ukraine. METHODS: Using data from a demonstration study of 12-week DAA conducted in Kyiv, we compared self-reported QOL as captured with the MOS-SF20 at study entry and 12 weeks after treatment completion (week 24). We calculated domain scores for health perception, physical, role and social functioning, mental health and pain to at entry and week 24, stratified by HIV status. RESULTS: Among the 857 patients included in the final analysis, health perception was the domain that showed the largest change, with an improvement of 85.7% between entry and week 24. The improvement was larger among those who were HIV negative (104.4%) than among those living with HIV (69.9%). Other domains that showed significant and meaningful improvements were physical functioning, which improved from 80.5 (95% CI 78.9-82.1) at study entry to 89.4 (88.1-90.7) at 24 weeks, role functioning (64.5 [62.3-66.8] to 86.5 [84.9-88.2]), social functioning (74.2 [72.1-76.2] to 84.8 [83.2-86.5]) and bodily pain (70.1 [68.2-72.0] to 89.8 [88.5-91.1]). Across all domains, QOL improvements among PLHIV were more modest than among HIV-negative participants. CONCLUSION: QOL improved substantially across all domains between study entry and week 24. Changes over the study period were smaller among PLHIV.
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Infecciones por VIH , Hepatitis C Crónica , Hepatitis C , Abuso de Sustancias por Vía Intravenosa , Adulto , Antivirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Hepacivirus , Hepatitis C/epidemiología , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Dolor/tratamiento farmacológico , Calidad de Vida , Abuso de Sustancias por Vía Intravenosa/tratamiento farmacológico , Ucrania/epidemiologíaRESUMEN
Miniaturized real-time fiber optic sensing systems with high sensing performance are in extreme demand. In this work, we propose a novel photonic quasicrystal fiber sensor in the terahertz region and test its sensing characteristics using the finite element method. The proposed simulated sensor numerically investigates the cancer-infected cells from the normal cells in the human cervix, blood, adrenal glands, and breast based on the difference in their refractive index changes. The effective refractive index of core-guided mode is due to the interaction of light between the refractive index of the fiber material and infiltrated normal and cancer cells, respectively. The proposed sensor exhibits a high birefringence of 0.03, a low dispersion of 0.35 ps/THz/cm, along with a high numerical aperture of 0.99. Besides, the sensor holds a less-effective material loss of 2.53 × 10-9 (dB/cm), a maximum power fraction of 88.10, a maximum relative sensitivity of 82.67%, and an effective mode area of 3.16 mm2. The results envisage that the proposed sensor displays high sensing performances with a rapid cancer detection mechanism.
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Tecnología de Fibra Óptica , Refractometría , Diseño de Equipo , Femenino , Humanos , Fotones , PorosidadRESUMEN
A novel, to the best of our knowledge, design of plastic optical fiber (POF) balloon-based refractive index sensor for the detection of different concentrations of sodium chloride is proposed and experimentally investigated. The experimental characterization supports the finding that the transmission loss is sensitive to the external environment's targeted refractive index changes of the analyte. The proposed sensor achieves a maximum intensity-based sensitivity of 3105 RIU-1, resolution of 3.22 ×10-7, and the figure of merit (FOM) is 326 RIU-1 from 2 to 2.5 Mol/L of the analyte with the chosen refractive index changes at 680 nm for a diameter D = 0.1 cm of the POF balloon structure. Furthermore, a high linear performance of 0.9896 is achieved with good robustness against the fabrication imperfection. The ultra-sensitiveness to the refractive index with a simple demonstration of the POF balloon-based structure has potential applications in the chemical, biological, and food safety sensing fields.
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Fibras Ópticas , Refractometría , Diseño de Equipo , Plásticos/químicaRESUMEN
While it is well known that maternal temperature affects fetal heart rate, the exact relationship is not well described. The circumstances accompanying most cases of maternal hypothermia and rewarming (e.g. a drowning event) have precluded a precise quantitative description of this relationship. We describe hypothermia and controlled rewarming during resection of a maternal brain stem tumor in the early third trimester. Continuous electronic fetal heart rate and core temperature monitoring demonstrated a near linear relationship during the development of hypothermia and rewarming. Recognition of the close relationship between maternal temperature and fetal heart rate can help safeguard maternal and fetal health, and prevent unnecessary delivery during non-obstetric surgery in pregnancy.
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Frecuencia Cardíaca Fetal , Hipotermia , Bradicardia , Craneotomía , Femenino , Frecuencia Cardíaca , Humanos , Hipotermia/terapia , Embarazo , Recalentamiento , TemperaturaRESUMEN
Chronic diseases have been treated using the phytochemical concepts of ethnomedicinal plant-derived herbal products. Terminalia arjuna, a significant ethnomedicinal plant, was revisited and reconnoitred for antioxidant, free radical scavenging, and DNA nicking inhibiting activity under H2O2 conditions using 21 solvent extracts. Ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid, and nitrous oxide scavenging (%) were found to have a strong positive association and interaction (PCA 1 explains 84.54% variation) with ethanol bark (Etoh-AB) (Meoh-AF). TPC (144.67-1794 µg/mL GAE) and TFC (2.5-34 µM Fe(II)/g were highest in Etoh-AB. In a pattern of combined solvent extracts, Etoh-AB had the highest antioxidant capacity, accompanied by Etoh-AL ≥ Meoh-AB ≥ Dw-AF. With R2 = 0.94, the DNA nicking inhibition behaviour parameters relative front, relative quantity, band (%), and lane (%) formed a positive significant (p < 0.01) connection. For the first time, we show that Etoh-AB nicks supercoiled, circular plasmid DNA in a way that is comparable to normal antioxidants. Normal antioxidants with the ability to prevent DNA nicking include Butylated hydroxy anisole < Butylated hydroxy toluene < ascorbic acid < and Gallic acid. Gallic acid (m/z 170.0208 g/mol) and Ellagic acid (m/z 302.0063 g/mol were present in high concentrations in solvent extracts. 0.48 mg was found to be the effective concentration for inhibiting relative DNA nicking. The current study is the first of its kind to show that steroid concentrations are higher in bark fractions of acetone, ethanol, and methanol. Furthermore, T. arjuna solvent extracts provide a wealth of information on phytochemical profiling, antioxidant ability, and DNA nicking inhibition, which may be useful for exploring the natural way and further research to develop a remedy against geriatric chronic disease. Despite the fact that ethanol is very close to methanol in terms of solvent toxicity, the current study identified it as the preferred solvent. Thus, the current research revisits previous studies and explores the potentiality of non-polar and polar aprotic and polar protic solvent systems, which lend credence to bioactive compounds that may be useful in isolating and formulating safe and cost effective herbal medicament for livestocks and aquaculture, and drugs for deoxygenerative human diseases, and can also be investigated further to instil environmental frugality.
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Cognición/efectos de los fármacos , ADN/metabolismo , Depuradores de Radicales Libres/farmacología , Extractos Vegetales/farmacología , Solventes/química , Terminalia/química , Antioxidantes/farmacología , Compuestos de Bifenilo/farmacología , Fitoquímicos/análisis , Picratos/farmacología , Análisis de Componente PrincipalRESUMEN
A novel fiber Michelson interferometer (FMI) based on parallel dual polarization maintaining fiber Sagnac interferometers (PMF-SIs) is proposed and experimentally demonstrated for temperature sensing. The free spectral range (FSR) difference of dual PMF-SIs determines the FSR of envelope and sensitivity of the sensor. The temperature sensitivity of parallel dual PMF-SIs is greatly enhanced by the Vernier effect. Experimental results show that the temperature sensitivity of the proposed sensor is improved from -1.646 nm/°C (single PMF-SI) to 78.984 nm/°C (parallel dual PMF-SIs), with a magnification factor of 47.99, and the temperature resolution is improved from ±0.03037°C to ±0.00063°C by optimizing the FSR difference between the two PMF-SIs. Our proposed ultrasensitive temperature sensor is with easy fabrication, low cost and simple configuration which can be implemented for various real applications that need high precision temperature measurement.
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INTRODUCTION: Testing for anti-TB drugs in small hair samples may serve as a non-invasive tool to measure cumulative drug exposure and/or adherence, as these determine treatment success. We aimed to assess how well hair assays of TB drugs predict TB treatment outcomes.METHODS: A small thatch of hair, ~30 strands, was cut from the occipital region in adults and children from a prospective TB cohort in India. Isoniazid (INH), acetyl-INH and pyrazinamide (PZA) were extracted from the hair samples and quantified using liquid-chromatography-tandem mass spectrometry. The relationship between drug concentrations in hair and time to unfavourable outcomes was assessed using Cox-proportional hazards regression models.RESULTS: A two-fold increase in hair acetyl-INH concentrations in the 264 participants in our cohort with hair assays for TB drugs indicated a lower hazard of unfavourable TB treatment outcomes (aHR 0.67, 95%CI 0.44-1.02) and TB treatment failure (aHR 0.65, 95%CI 0.42-1.01). Higher summed concentrations (a summed measure of INH and acetyl-INH) indicated a lower hazard of treatment failure (aHR 0.69, 95%CI 0.45-1.05)CONCLUSION: Hair levels of INH and its metabolite may predict TB treatment outcomes, indicating the potential utility of this measure to assess and optimise TB treatment outcomes.
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Preparaciones Farmacéuticas , Tuberculosis , Adulto , Antituberculosos/uso terapéutico , Niño , Humanos , India , Isoniazida , Estudios Prospectivos , Pirazinamida/uso terapéutico , Rifampin , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológicoAsunto(s)
Aorta/patología , Enfermedad de la Válvula Aórtica/diagnóstico por imagen , Síndrome de Loeys-Dietz/diagnóstico por imagen , Ultrasonografía Prenatal , Aorta/diagnóstico por imagen , Aorta/embriología , Enfermedad de la Válvula Aórtica/congénito , Enfermedad de la Válvula Aórtica/embriología , Dilatación Patológica/diagnóstico por imagen , Dilatación Patológica/embriología , Dilatación Patológica/genética , Femenino , Humanos , Nacimiento Vivo , Síndrome de Loeys-Dietz/embriología , Síndrome de Loeys-Dietz/genética , Ilustración Médica , Embarazo , Adulto JovenRESUMEN
Primary central nervous system lymphoma (PCNSL) is confined to the brain, eyes, and cerebrospinal fluid without evidence of systemic spread. Rarely, PCNSL occurs in the context of immunosuppression (eg, posttransplant lymphoproliferative disorders or HIV [AIDS-related PCNSL]). These cases are poorly characterized, have dismal outcome, and are typically Epstein-Barr virus (EBV)-associated (ie, tissue-positive). We used targeted sequencing and digital multiplex gene expression to compare the genetic landscape and tumor microenvironment (TME) of 91 PCNSL tissues all with diffuse large B-cell lymphoma histology. Forty-seven were EBV tissue-negative: 45 EBV- HIV- PCNSL and 2 EBV- HIV+ PCNSL; and 44 were EBV tissue-positive: 23 EBV+ HIV+ PCNSL and 21 EBV+ HIV- PCNSL. As with prior studies, EBV- HIV- PCNSL had frequent MYD88, CD79B, and PIM1 mutations, and enrichment for the activated B-cell (ABC) cell-of-origin subtype. In contrast, these mutations were absent in all EBV tissue-positive cases and ABC frequency was low. Furthermore, copy number loss in HLA class I/II and antigen-presenting/processing genes were rarely observed, indicating retained antigen presentation. To counter this, EBV+ HIV- PCNSL had a tolerogenic TME with elevated macrophage and immune-checkpoint gene expression, whereas AIDS-related PCNSL had low CD4 gene counts. EBV-associated PCNSL in the immunosuppressed is immunobiologically distinct from EBV- HIV- PCNSL, and, despite expressing an immunogenic virus, retains the ability to present EBV antigens. Results provide a framework for targeted treatment.
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Neoplasias del Sistema Nervioso Central/etiología , Neoplasias del Sistema Nervioso Central/inmunología , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/inmunología , Herpesvirus Humano 4/inmunología , Linfoma/virología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Sistema Nervioso Central/genética , Neoplasias del Sistema Nervioso Central/virología , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/virología , Femenino , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Tolerancia Inmunológica , Linfoma/etiología , Masculino , Persona de Mediana Edad , Mutación , Transcriptoma , Microambiente TumoralRESUMEN
The promising advancement of supercontinuum generation in optical fibers has initiated significant interest in recent research studies and several continuing applications. We numerically corroborate the effects of picosecond pulse pumped supercontinuum (SC) by using two weak continuous-wave (CW) triggers with 1% pump intensity. Compared with SC with one CW trigger, adding two CW triggers (1% pump power), both near the modulation instability peaks, can achieve wider spectra for a picosecond pulse pumped SC. Furthermore, good coherence properties may be achieved in the wavelength range from 1300-2000 nm when one CW trigger is near the pump center wavelength and the other CW trigger is distant from the pump. In our simulations, putting two CW triggers on the same side (concerning the pump wavelength) or putting them on different sides have similar effects on SC spectral and temporal coherence properties. Therefore, by engineering the wavelengths of two CW triggers to offer better bandwidth or coherence, we envision that the proposed technique could play a significant role in the generation of SC.
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The emerging development of sensing technology initiates innovative sensors achieving low-cost to facilitate practical realization. An interesting crush of the work is to propose a simple structural sensor and to analyze the different schemes of the metal coating by stimulated emission of Raman scattering (SERS) intensification. For the first time, we propose a simple geometrical photonic crystal fiber refractive index based sensor (PCF-RIBS) with three different Schemes A, B, and C, i.e., gold (A) layer-coated surface plasmon resonance (SPR) based D-type PCF-RIBS; Au with titanium-di-oxide (TiO2) layer-coated SPR D-type PCF-RIBS; and Au + TiO2 grating-coated localized surface plasmon resonance (LSPR) D-type PCF-RIBS. Characterizing the three different Schemes A, B, and C using finite element method simulation shows, a maximum wavelength sensitivity of 48,000 nm/RIU, 52,000 nm/RIU and 75,000 nm/RIU, respectively, for a wide range of analyte-refractive index from 1.33 to 1.45 and operates in the wavelength range from 500-2000 nm. Of all the Schemes, Scheme C is found to excite a relatively larger number of surface-plasmons. Eventually, it exhibits improved sensing performances compared to SPR based Schemes A and B. Consequently, it would turn out to be an appropriate candidate to detect a broad range of biological and chemical sample detection.