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1.
Opt Lett ; 49(5): 1333-1336, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38427006

RESUMEN

This Letter proposes a novel, to the best of our knowledge, matrix digitization method for a photonic analog-to-digital converter with phase-shifted optical quantization (PSOQ-ADC). This method overcomes the issues of excessive bit width of the output code and the generation of invalid codes encountered by the traditional direct digitization method. A PSOQ-ADC was fabricated on a lithium niobate on insulator (LNOI) platform, and an experimental platform was built. The results show that RF signals at 1/2/5 GHz, which were sampled by a 50GS/s optical pulse train, were digitized successfully with the matrix digitization method, producing 5-bit codes without invalid codes. In comparison, the direct digitization method yields 10-bit codes, and as the optical signal-to-noise ratio (OSNR) decreases, the ratio of invalid codes increases in the direct digitization method; even with Hamming distance correction, its effective number of bits (ENOB) remains smaller than that of the matrix digitization.

2.
Eur J Clin Microbiol Infect Dis ; 43(5): 809-820, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38383889

RESUMEN

PURPOSE: Several model studies suggested the implementation of latent tuberculosis infection (LTBI) testing and treatment could greatly reduce the incidence of tuberculosis (TB) and achieve the 2035 target of the "End TB" Strategy in China. The present study aimed to evaluate the cost-effectiveness of LTBI testing and TB preventive treatment among key population (≥ 50 years old) susceptible to TB at community level in China. METHODS: A Markov model was developed to investigate the cost-effectiveness of LTBI testing using interferon gamma release assay (IGRA) and subsequent treatment with 6-month daily isoniazid regimen (6H) (as a standard regimen for comparison) or 6-week twice-weekly rifapentine and isoniazid regimen (6-week H2P2) in a cohort of 10,000 adults with an average initial age of 50 years. RESULTS: In the base-case analysis, LTBI testing and treatment with 6H was dominated (i.e., more expensive with a lower quality-adjusted life year (QALY)) by LTBI testing and treatment with 6-week H2P2. LTBI testing and treatment with 6-week H2P2 was more effective than no intervention at a cost of $20,943.81 per QALY gained, which was below the willingness-to-pay (WTP) threshold of $24,211.84 per QALY gained in China. The one-way sensitivity analysis showed the change of LTBI prevalence was the parameter that most influenced the results of the incremental cost-effectiveness ratios (ICERs). CONCLUSION: As estimated by a Markov model, LTBI testing and treatment with 6-week H2P2 was cost-saving compared with LTBI testing and treatment with 6H, and it was considered to be a cost-effective option for TB control in rural China.


Asunto(s)
Antituberculosos , Análisis Costo-Beneficio , Ensayos de Liberación de Interferón gamma , Isoniazida , Tuberculosis Latente , Población Rural , Humanos , Tuberculosis Latente/tratamiento farmacológico , Tuberculosis Latente/epidemiología , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/economía , China/epidemiología , Persona de Mediana Edad , Antituberculosos/uso terapéutico , Antituberculosos/economía , Antituberculosos/administración & dosificación , Ensayos de Liberación de Interferón gamma/economía , Isoniazida/uso terapéutico , Isoniazida/economía , Isoniazida/administración & dosificación , Masculino , Técnicas de Apoyo para la Decisión , Femenino , Anciano , Rifampin/uso terapéutico , Rifampin/análogos & derivados , Rifampin/economía , Rifampin/administración & dosificación , Cadenas de Markov , Años de Vida Ajustados por Calidad de Vida
3.
Opt Express ; 31(20): 33333-33342, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37859116

RESUMEN

We propose what we believe to be a novel approach to enhance the dynamic range of a photonic analog-to-digital converter (PADC) without the need of additional custom-designed circuits or components. The method utilizes the unique characteristic of our previously reported multimode interference (MMI) coupler-based optical quantizer that exploits the periodicity of the optical phase to realize a modulo operation. Experiments were carried out to verify the effectiveness of the proposed method on our phase-shifted optical quantization ADC (PSOQ-ADC) chip. Experimental results show that our proposed method enhance the dynamic range from [-V π, V π] to [-2V π, 2V π] and has the potential to be further extended. Additionally, we successfully reconstructed radio frequency (RF) signals at a sampling rate of 30 Gs/s. Our work provides a promising solution for achieving a high dynamic range in on-chip PSOQ-ADC.

4.
Opt Express ; 31(2): 890-906, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36785136

RESUMEN

The particle composition of suspended matter provides crucial information for a deeper understanding of marine biogeochemical processes and environmental changes. Particulate backscattering efficiency (Qbbe(λ)) is critical to understand particle composition, and a Qbbe(λ)-based model for classifying particle types was proposed. In this study, we evaluated the applicability of the Qbbe(λ)-based model to satellite observations in the shallow marginal Bohai and Yellow Seas. Spatiotemporal variations of the particle types and their potential driving factors were studied. The results showed that the Qbbe(λ) products generated from Moderate Resolution Imaging Spectroradiometer (MODIS) on the satellite Aqua agreed well with the in situ measured values, with determination coefficient, root mean square error, bias, and mean absolute percentage error of 0.76, 0.007, 16.5%, and 31.0%, respectively. This result verifies the satellite applicability of the Qbbe(λ)-based model. Based on long-term MODIS data, we observed evident spatiotemporal variations of the Qbbe(λ), from which distinct particle types were identified. Coastal waters were often dominated by minerals, with high Qbbe(λ) values, though their temporal changes were also observed. In contrast, waters in the offshore regions showed clear changes in particle types, which shifted from organic-dominated with low Qbbe(λ) levels in summer to mineral-dominated with high Qbbe(λ) values in winter. We also observed long-term increasing and decreasing trends in Qbbe(λ) in some regions, indicating a relative increase in the proportions of mineral and organic particles in the past decades, respectively. These spatiotemporal variations of Qbbe(λ) and particle types were probably attributed to sediment re-suspension related to water mixing driven by wind and tidal forcing, and to sediment load associated with river discharge. Overall, the findings of this study may provide valuable proxies for better studying marine biogeochemical processes, material exchanges, and sediment flux.

5.
Glob Chang Biol ; 29(16): 4511-4529, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37231532

RESUMEN

Marine phytoplankton fuel the oceanic biotic chain, determine the carbon sequestration levels, and are crucial for the global carbon cycle and climate change. In the present study, we show a near-two-decadal (2002-2022) spatiotemporal distribution of global phytoplankton abundance, proxy as dominant phytoplankton taxonomic groups (PTGs), with a newly developed remote sensing model. Globally, six chief PTGs, namely chlorophytes (~26%), diatoms (~24%), haptophytes (~15%), cryptophytes (~10%), cyanobacteria (~8%), and dinoflagellates (~3%), explain most of the variation (~86%) in phytoplankton assemblages. Spatially, diatoms generally dominate high latitudes, marginal seas, and coastal upwelling zones, whereas chlorophytes and haptophytes control the open oceans. Satellite observations reveal a gentle multi-annual trend of the PTGs in the major oceans, indicative of roughly "unchanged" conditions on the total biomass or compositions of the phytoplankton community. Jointly, "changed" status applies to a short-term (seasonal) timescale: (1) Fluctuations of PTGs exhibit different amplitudes among different subregions, together with a general rule-more intense vibration in the Northern Hemisphere and polar oceans than other zones; (2) diatoms and haptophytes vary more dramatically than other PTGs in a global-scale scope. These findings provide a clear picture of the global phytoplankton community composition and can improve our understanding of their state and further analysis of marine biological processes.


Asunto(s)
Cianobacterias , Diatomeas , Dinoflagelados , Fitoplancton , Océanos y Mares
6.
BMC Infect Dis ; 23(1): 373, 2023 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-37270474

RESUMEN

BACKGROUND: Individuals in close contact with active pulmonary tuberculosis (TB) patients showed a high risk of recent infection and, once infected, higher risk of developing active TB in the following years post-exposure. But the peak time of active disease onset is unclear. This study aims to estimate post exposure TB incidence risk among close contacts to provide reference for clinical and public health strategies. METHODS: We searched PubMed, Web of Science, and EMBASE for articles published until December 1, 2022. The incidence rates were quantitatively summarized by means of meta-analysis using the random-effect model. RESULTS: Of the 5616 studies, 31 studies included in our analysis. For baseline close contacts results, the summarized prevalence of Mycobacterium tuberculosis (MTB) infection and active TB was found to be 46.30% (95% CI: 37.18%-55.41%) and 2.68% (95% CI: 2.02%-3.35%), respectively. During the follow-up, the 1-year, 2-year and 5-year cumulative incidence of TB in close contacts were 2.15% (95% CI: 1.51%-2.80%), 1.21% (95% CI: 0.93%-1.49%) and 1.11% (95% CI: 0.64%-1.58%), respectively. Individuals with a positive result of MTB infection testing at baseline showed significantly higher cumulative TB incidence as compared to those negatives (3.80% vs. 0.82%, p < 0.001). CONCLUSIONS: Individuals with close contact to active pulmonary TB patients are bearing significant risk of developing active TB, particularly within the first-year post-exposure. Population with recent infections should be an important priority for active case finding and preventive intervention worldwide.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Pulmonar , Tuberculosis , Humanos , Incidencia , Trazado de Contacto/métodos , Tuberculosis/epidemiología , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/prevención & control
7.
World J Surg ; 47(4): 948-961, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36681771

RESUMEN

BACKGROUND: Acute kidney injury (AKI) is a major complication that occurs following an operation. Therefore, there is an increasing need to discover new predictors of AKI. We hypothesized that the preoperative neutrophil-to-lymphocyte ratio (NLR) was associated with postoperative AKI and in-hospital mortality following noncardiac surgery. METHODS: This is a retrospective observational study of patients who underwent noncardiac surgery at Sichuan University West China Hospital from 2018 to 2020. Multivariable logistic regression was performed as the major analytic method. In addition, sensitivity and subgroup analyses were performed to validate the results. RESULTS: A total of 44,065 patients were included in this study. The prevalence of postoperative AKI was 5.62%, and the in-hospital mortality was 1.58%. Multivariable analysis demonstrated that NLR ≥ 5 was independently associated with the development of postoperative AKI (OR 1.42, 1.24-1.73; P < 0.001) and in-hospital mortality (OR 2.03, 1.63-2.52; P < 0.001). Similar results were achieved when propensity-score matching was performed for patients with NLR ≥ 5 and < 5 on the baseline. In stratified analysis, the associations remained persistent in most subgroups. For the sensitivity analysis, we took NLR as a continuous variable and demonstrated the potential linear relationship between NLR and postoperative AKI and mortality. CONCLUSIONS: Our results indicated that preoperative NLR is associated with the prevalence of postoperative AKI and in-hospital mortality that occur after major noncardiac surgery. These findings suggest that NLR has the potential to be a significant correlation biomarker associated with perioperative risk assessment of patients undergoing noncardiac surgeries.


Asunto(s)
Lesión Renal Aguda , Recuento de Leucocitos , Linfocitos , Neutrófilos , Procedimientos Quirúrgicos Operativos , Humanos , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/etiología , Lesión Renal Aguda/mortalidad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/mortalidad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Procedimientos Quirúrgicos Operativos/efectos adversos , Procedimientos Quirúrgicos Operativos/mortalidad , Mortalidad Hospitalaria , Periodo Preoperatorio
8.
Prostate ; 82(5): 566-575, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35067945

RESUMEN

BACKGROUND: To determine the prostate cancer biochemical recurrence-related fusion biopsy characteristics before radical surgery and to establish the risk prediction model of biochemical recurrence of prostate cancer. METHODS: Three hundred and four patients undergoing radical surgery for prostate cancer at Huadong Hospital affiliated to Fudan University between 2009 and 2020 for preoperative magnetic resonance imaging (MRI) before biopsy with suspicious prostate cancer lesions. Each case was followed by a 10 + x needle combination of targeted biopsy (intentional or robotic fusion) with systematic biopsy. Prostate-specific antigen levels were measured at 1, 3, and 6 months postoperatively, followed by reexamination every 6 months. Survival analysis was performed by the Kaplan-Meier method, univariate and multivariate analysis by Cox, and Logistic risk regression models. RESULTS: Higher Prostate Imaging Reporting And Data System (PI-RADS) scores (p < 0.001), suspicious extracapsular invasion (p < 0.001), and seminal vesicle invasion (p < 0.001) on MRI, the largest lesion diameter on MRI (p = 0.006), higher biopsy International Society of Urological Pathology (ISUP) grade group (p < 0.001) related to higher biochemical recurrence rates, higher pathological staging (p < 0.001), and a greater probability of local lymph node metastasis (p < 0.001). We accurately predicted the biochemical recurrence of prostate cancer after radical surgery based on preoperative features including the long diameter of the largest MRI lesion more than 23 mm, seminal vesicle invasion on MRI, and targeted fusion biopsy ISUP grade >3 Risk stratified classification (AUC = 0.729, p < 0.001). In our cohort, this risk stratification had a larger area under the curve than predictive models based only on magnetic resonance parameters and traditional risk scores. CONCLUSIONS: In this cohort, seminal vesicle invasion on MRI, the long diameter of the largest MRI lesion, and targeted fusion biopsy ISUP grade grope are significantly predictive of pathologic features and biochemical recurrence after prostate surgery. The risk stratification integrating the three parameters could better predict the biochemical recurrence than the traditional model.


Asunto(s)
Próstata , Neoplasias de la Próstata , Humanos , Biopsia Guiada por Imagen/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Próstata/diagnóstico por imagen , Próstata/patología , Próstata/cirugía , Prostatectomía/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/cirugía , Estudios Retrospectivos , Vesículas Seminales/patología
9.
Eur Respir J ; 60(1)2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34764183

RESUMEN

BACKGROUND: Enlarging tuberculosis (TB) preventive treatment among at-risk populations is a critical component of the End TB Strategy. There is an urgent need to develop suitable latent tuberculosis infection (LTBI) testing and treatment tools according to the local TB epidemic and available resources worldwide. METHODS: Based on an open-label randomised controlled trial conducted since 2015 in China among rural residents aged 50-70 years with LTBI, the protective efficacy of a 6-week twice-weekly regimen of rifapentine plus isoniazid was further evaluated in a 5-year follow-up survey. RESULTS: 1298 treated participants and 1151 untreated controls were included in the 5-year protective efficacy analysis. In the per-protocol analysis, the incidence rate was 0.49 (95% CI 0.30-0.67) per 100 person-years in the untreated control group and 0.19 (95% CI 0.07-0.32) per 100 person-years in the treated group; the protection rate was 61.22%. Subgroup analysis showed that the protection rate was 76.82% in the per-protocol analysis among participants with baseline interferon (IFN)-γ levels in the highest quartile (≥3.25 IU·mL-1). Multiple logistic regression analysis indicated that participants with baseline body mass index <18.5 kg·m-2 and with pulmonary fibrotic lesions had increased hazard of developing active disease with an adjusted hazard ratio (aHR) of 3.64 (95% CI 1.20-11.00) and 5.99 (95% CI 2.20-16.27), respectively. In addition, individuals with higher baseline IFN-γ levels showed an increased risk of TB occurrence (aHR 2.27, 95% CI 1.13-4.58). CONCLUSIONS: Our findings suggest the 6-week twice-weekly regimen of rifapentine plus isoniazid for LTBI treatment might be an optional tool for TB control in the Chinese population.


Asunto(s)
Tuberculosis Latente , Antituberculosos/uso terapéutico , China/epidemiología , Estudios de Seguimiento , Humanos , Isoniazida/uso terapéutico , Tuberculosis Latente/tratamiento farmacológico , Tuberculosis Latente/epidemiología , Población Rural
10.
Microb Cell Fact ; 20(1): 158, 2021 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-34399754

RESUMEN

4-Androstene-3,17-dione (4-AD), 1,4-androstadiene-3,17-dione (ADD) and 9α-hydroxyl-4-androstene-3,17-dione (9OH-AD), which are important starting compounds for the synthesis of steroidal medicines, can be biosynthetically transformed from phytosterols by Mycobacterium strains. Genomic and metabolic analyses have revealed that currently available 4-AD-producing strains maintain the ability to convert 4-AD to ADD and 9OH-AD via 3-ketosteroid-1,2-dehydrogenase (KstD) and 3-ketosteroid-9α-hydroxylase (Ksh), not only lowering the production yield of 4-AD but also hampering its purification refinement. Additionally, these 4-AD industrial strains are excellent model strains to construct ADD- and 9OH-AD-producing strains. We recently found that Mycobacterium neoaurum HGMS2, a 4-AD-producing strain, harbored fewer kstd and ksh genes through whole-genomic and enzymatic analyses, compared with other strains (Wang et al. in Microbial Cell Fact 19:187, 2020). In this study, we attempted to construct an efficient 4-AD-producing strain by knocking out the kstd and ksh genes from the M. neoaurum HGMS2 strain. Next, we used kstd- and ksh-default HGMS2 mutants as templates to construct ADD- and 9OH-AD-producing strains by knocking in active kstd and ksh genes, respectively. We found that after knocking out its endogenous kstd and ksh genes, one of these knockout mutants, HGMS2Δkstd211 + ΔkshB122, showed a 20% increase in the rate of phytosterol to 4-AD conversion, compared relative to the wild-type strain and an increase in 4-AD yield to 38.3 g/L in pilot-scale fermentation. Furthermore, we obtained the ADD- and 9OH-AD-producing strains, HGMS2kstd2 + Δkstd211+ΔkshB122 and HGMS2kshA51 + Δkstd211+ΔkshA226, by knocking in heterogenous active kstd and ksh genes to selected HGMS2 mutants, respectively. During pilot-scale fermentation, the conversion rates of the ADD- and 9OH-AD-producing mutants transforming phytosterol were 42.5 and 40.3%, respectively, and their yields reached 34.2 and 37.3 g/L, respectively. Overall, our study provides efficient strains for the production of 4-AD, ADD and 9OH-AD for the pharmaceutical industry and provides insights into the metabolic engineering of the HGMS2 strain to produce other important steroidal compounds.


Asunto(s)
Androstenodiona/análogos & derivados , Androstenodiona/metabolismo , Mycobacterium/genética , Mycobacterium/metabolismo , Fitosteroles/metabolismo , Hidroxilación , Oxigenasas de Función Mixta
11.
J Autom Reason ; 65(5): 691-709, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720282

RESUMEN

In this article we present an ongoing effort to formalise quantum algorithms and results in quantum information theory using the proof assistant Isabelle/HOL. Formal methods being critical for the safety and security of algorithms and protocols, we foresee their widespread use for quantum computing in the future. We have developed a large library for quantum computing in Isabelle based on a matrix representation for quantum circuits, successfully formalising the no-cloning theorem, quantum teleportation, Deutsch's algorithm, the Deutsch-Jozsa algorithm and the quantum Prisoner's Dilemma. We discuss the design choices made and report on an outcome of our work in the field of quantum game theory.

12.
Microb Cell Fact ; 19(1): 187, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33008397

RESUMEN

Mycobacterium neoaurum strains can transform phytosterols to 4-androstene-3,17-dione (4-AD), a key intermediate for the synthesis of advanced steroidal medicines. In this work, we presented the complete genome sequence of the M. neoaurum strain HGMS2, which transforms ß-sitosterol to 4-AD. Through genome annotation, a phytosterol-degrading pathway in HGMS2 was predicted and further shown to form a 9,10-secosteroid intermediate by five groups of enzymes. These five groups of enzymes included three cholesterol oxidases (ChoM; group 1: ChoM1, ChoM2 and Hsd), two monooxygenases (Mon; group 2: Mon164 and Mon197), a set of enzymes for side-chain degradation (group 3), one 3-ketosteroid-1,2-dehydrogenase (KstD; group 4: KstD211) and three 3-ketosteroid-9a-hydroxylases (Ksh; group 5: KshA226, KshA395 and KshB122). A gene cluster encoding Mon164, KstD211, KshA226, KshB122 and fatty acid ß-oxidoreductases constituted one integrated metabolic pathway, while genes encoding other key enzymes were sporadically distributed. All key enzymes except those from group 3 were prepared as recombinant proteins and their activities were evaluated, and the proteins exhibited distinct activities compared with enzymes identified from other bacterial species. Importantly, we found that the KstD211 and KshA395 enzymes in the HGMS2 strain retained weak activities and caused the occurrence of two major impurities, i.e., 1,4-androstene-3,17-dione (ADD) and 9-hydroxyl-4-androstene-3,17-dione (9OH-AD) during ß-sitosterol fermentation. The concurrence of these two 4-AD analogs not only lowered 4-AD production yield but also hampered 4-AD purification. HGMS2 has the least number of genes encoding KstD and Ksh enzymes compared with current industrial strains. Therefore, HGMS2 could be a potent strain by which the 4-AD production yield could be enhanced by disabling the KstD211 and KshA395 enzymes. Our work also provides new insight into the engineering of the HGMS2 strain to produce ADD and 9OH-AD for industrial application.


Asunto(s)
Androstenodiona/biosíntesis , Mycobacteriaceae/enzimología , Mycobacteriaceae/genética , Fitosteroles/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Redes y Vías Metabólicas , Secuenciación Completa del Genoma
13.
Opt Express ; 27(16): A1156-A1172, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31510497

RESUMEN

Knowing variations of phytoplankton community characteristics is of great significance to many marine ecological and biogeochemical processes in oceanography and related fields research. Satellite remote sensing provides the only viable path for continuously detecting phytoplankton community characteristics in the large-scale spatial areas. However, remote sensing approaches are currently hindered by limited understanding on reflectance responses to variations from phytoplankton community compositions and further do not achieve a true application by satellite observations. Here we analyze in situ observation data sets from three cruises in a dynamic marine environment covering those coastal water areas in the marginal seas of the Pacific Northwest (Bohai Sea, Yellow Sea, and East China Sea). The size/species-specific phytoplankton assemblages can be quantitatively defined by the high-performance liquid chromatography (HPLC)-derived phytoplankton pigments and customized diagnostic pigment analysis, as well as a matrix factorization "CHEMTAX" program. Therein, note that a suit of updated weight values for diagnostic pigments are proposed with better performance than others. The above-mentioned size/species-specific phytoplankton assemblages include three size classes, i.e., micro-, nano-, and picoplankton, and eight species typically existing in the investigated water areas. Relationship analysis illustrates us that relatively close and robust models can be established to associate three size-specific and four dominant species-specific phytoplankton biomasses with the total chlorophyll a. Those models are then applied to the Geostationary Ocean Color Imager (GOCI) images for the whole 2015 year, which generated annual mean distributions of size/species-specific phytoplankton biomasses. The current study represents a meaningful attempt to achieve the satellite remote-sensing retrievals on the phytoplankton community composition, especially the species-specific phytoplankton biomass in the study region.

14.
Opt Express ; 27(4): 4528-4548, 2019 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-30876071

RESUMEN

Several algorithms have been proposed to detect floating macroalgae blooms in the global ocean. However, some of them are difficult or even impossible to routinely apply by non-experts because of performing a sophisticated atmospheric correction scheme or due to the mismatch in spectral bands from one sensor to another. Here, a generic, simple and effective method, referred to as the Floating Green Tide Index (FGTI), was proposed to detect floating green macroalgae blooms (GMB). The FGTI was defined as the difference between greenness and wetness features extracted from digital number (DN) observation through Tasseled Cap Transformation analysis, providing the advantage of bypassing the atmospheric correction procedure. Through cross-index and cross-sensor comparisons, the FGTI showed similar performance to the existing VB-FAH (Virtual-Baseline Floating macroAlgae Height) and FAI (Floating Algae Index) algorithms but proved more robust than the traditional NDVI (Normalized Difference Vegetation Index) in terms of response to perturbations by environmental conditions, viewing geometry, sun glint, and thin cloud contamination. Given the requirement for spectral bands in the current and planned satellite sensors, the FGTI design can easily be extended to any satellite sensor, and therefore provide an excellent data resource for studying GMB in any part of the global ocean.


Asunto(s)
Chlorophyta/crecimiento & desarrollo , Monitoreo del Ambiente/métodos , Tecnología de Sensores Remotos , Algas Marinas/crecimiento & desarrollo , Algoritmos , Chlorophyta/química , Océano Pacífico , Algas Marinas/química , Contaminantes del Agua/análisis
15.
Opt Express ; 27(3): 3074-3090, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30732334

RESUMEN

Using two field cruise observations collected during September and December 2016 in the Bohai Sea (BS), Yellow Sea (YS), and East China Sea (ECS), our study explores the variability of the particulate backscattering ratio (i.e., a ratio of particulate backscattering, bbp in m-1, to particulate scattering, bp in m-1, denoted as b˜bp, dimensionless). A large variation of b˜bp (using 550 nm as a delegate) in magnitude is observed in the study regions, ranging from 0.0004 to 0.043 (with an average of 0.015 ± 0.0082), which implies optically complex water conditions. Spectral variation in b˜bp is analyzed quantitatively by our proposed so-called "spectral dependence index," K, recommended as a standard way to determine quantitatively the spectral dependence of b˜bp in water bodies worldwide. The driving mechanism on the b˜bp variability in the study regions is researched for the first time, based on those synchronous data on particle intrinsic attributes, herein mainly referring to particle concentration (TSM, for the content of total suspended matter), composition (using a ratio of Chla/TSM as a surrogate, where Chla refers to the content of chlorophyll a), mean particle size (DA), and mean apparent density (ρa). The TSM, Chla/TSM, and DA cumulatively contribute most (97.8%) of the b˜bp variability, while other factors, such as the ρa, show a weak influence (0.04%). Meanwhile, we model b˜bp with direct linkages to TSM, Chla/TSM, and DA by using a linear regression method, with low estimation errors (such as mean absolute percentage error, MAPE, of about 14%). In short, our findings promote an understanding on the essence of the b˜bp in the BS, YS, and ECS, and are significantly beneficial to the comprehensive grasp of those complex features on suspended particles and those related to biogeochemical processes in marine waters.

16.
Med Sci Monit ; 25: 8764-8776, 2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31746315

RESUMEN

BACKGROUND The epidermal growth factor receptor (EGFR) is a therapeutic target for non-small cell lung cancer (NSCLC), but knowledge on gene mutations that contribute to NSCLC development and persistence is lacking. In this study, we investigated genetic variations in EGFR and their association with the clinical and pathological factors of NSCLC. MATERIAL AND METHODS Clinical cases (331 patients) and The Cancer Genome Atlas (TCGA) cases (1040 patients) were selected and analyzed using the refractory mutation systems cBioPortal and the Tumor Immune Estimation Resource (TIMER). RESULTS EGFR mutation frequencies were 54.4% (180 of 331 patients) and 8.0% (83 of 1040 patients) in the clinical and TCGA cohorts, respectively. EGFR mutations were strongly associated with smoking and pathology (P≤0.05) in the clinical cohort, and with gender, smoking, and pathology (P=0.001, P<0.001, and P<0.001, respectively) in TCGA cohort. In cases of lung squamous carcinoma (LUSC), EGFR was overexpressed as a result of DNA amplification, but this amplified expression showed no association with the overall survival (OS) or progression-free survival of LUSC patients. EGFR gene alterations were, however, associated with worse OS in lung adenocarcinoma (LUAD) patients. Immune cell infiltrates from LUAD and LUSC tumors differed according to EGFR expression. EGFR mutations resulted in a decline of immune infiltration or a lack of infiltrating immune cells in the NSCLC microenvironment. CONCLUSIONS Mutational profiles of the EGFR in NSCLC patients provide useful information for the use of tyrosine kinase inhibitors for adjuvant or neoadjuvant therapy and immunotherapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , Adenocarcinoma/patología , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/patología , Estudios de Cohortes , Resistencia a Antineoplásicos/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Femenino , Humanos , Pulmón/patología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Mutación , Inhibidores de Proteínas Quinasas/uso terapéutico , Microambiente Tumoral
17.
Opt Express ; 26(23): 30556-30575, 2018 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-30469953

RESUMEN

Phytoplankton community is an important organism indicator of monitoring water quality, and accurately estimating its composition and biomass is crucial for understanding marine ecosystems and biogeochemical processes. Identifying phytoplankton species remains a challenging task in the field of oceanography. Phytoplankton fluorescence is an important biological property of phytoplankton, whose fluorescence emissions are closely related to its community. However, the existing estimation approaches for phytoplankton communities by fluorescence are inaccurate and complex. In the present study, a new, simple method was developed for determining the Chlorophytes, Chrysophytes, Cryptophytes, Diatoms, Dinoflagellates, and Prymnesiophytes based on the fluorescence emission spectra measured from the HOBI Labs Hydroscat-6P (HS-6P) in the Bohai Sea, Yellow Sea, and East China Sea. This study used single bands, band ratios, and band combinations of the fluorescence signals to test their correlations with the six dominant algal species. The optimal band forms were confirmed, i.e., X1 (i.e., fl(700), which means the fluorescence emission signal at 700 nm band) for Chlorophytes, Cryptophytes, Dinoflagellates, and Prymnesiophytes (R = 0.947, 0.862, 0.911, and 0.918, respectively) and X7 (i.e., [fl(700) + fl(550)]/[fl(550)/fl(700)], where fl(550) denotes the fluorescence emission signal at 550 nm band) for Chrysophytes and Diatoms (R = 0.893 and 0.963, respectively). These established models here show good performances, yielding low estimation errors (i.e., root mean square errors of 0.16, 0.02, 0.06, 0.36, 0.18, and 0.03 for Chlorophytes, Chrysophytes, Cryptophytes, Diatoms, Dinoflagellates, and Prymnesiophytes, respectively) between in situ and modeled phytoplankton communities. Meanwhile, the spatial distributions of phytoplankton communities observed from both in situ and fluorescence-derived results agreed well. These excellent outputs indicate that the proposed method is to a large extent feasible and robust for estimating those dominant algal species in marine waters. In addition, we have applied this method to three vertical sections, and the retrieved vertical spatial distributions by this method can fill the gap of the common optical remote sensing approach, which usually only detects the sea surface information. Overall, our findings indicate that the proposed method by the fluorescence emission spectra is a potentially promising way to estimate phytoplankton communities, in particular enlarging the profiling information.

18.
Fish Shellfish Immunol ; 66: 240-253, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28433718

RESUMEN

The present study reports the identification, and characterization of three new putative piscidin paralogues, ecPis-2, ecPis-3 and ecPis-4, from orange-spotted grouper (Epinephelus coioides). The cDNA of the three piscidins with the 207, 216, and 231 nt open reading frame encoded respectively a 68-, 71-, and 76-amino acid preprotein consisting of the predicted signal peptide, and putative mature peptide and prodomain. The phylogenetic analysis indicated that multiple piscidin paralogues in one fish species are highly diversified, the analysis suggested that the piscidins should be a family belonging to the superfamily of ancient cationic, linear, and amphipathic host defence peptides widespread across invertebrate and vertebrate taxa comprising insect cecropins and ceratotoxins, and the amphibian dermaseptins. The synthetic putative mature peptides, ecPis-2S, ecPis-3S and ecPis-4S, had strong activities against bacterial and fungal species. EcPis-3S exhibited powerful activity against the infective stage of Cryptocaryon irritans, theronts. The full length ecPis-2 and ecPis-4 by removal of signal peptide, ecPis-2L and ecPis-4L respectively, had potency against bacterial, fungal and parasitic species. The peptide ecPis-2S was proved to exist in spleen of orange-spotted grouper by HPLC followed by ESI-LCMS analysis. Basal transcriptions of ecPis-2, ecPis-3 and ecPis-4 were detected not only in the potential sites of pathogen entry such as gills, skin and intestine, but also in tissues such as head kidney, trunk kidney, blood cells, and spleen with highly abundant immune cells, however different paralogues expressed constitutively with different levels in the tissues. In addition, the expression of ecPis-2, ecPis-3 and ecPis-4 was upregulated in orange-spotted grouper challenged by Vibrio Parahaemolyticus, in different tissues at different time point after bacteria injection. These results support ecPis-2, ecPis-3 and ecPis-4 being the important immune-related genes in orange-spotted grouper innate immune system and playing multifunctional and complementary roles following their structural and functional diversification, and expression pattern difference. Finally, this study facilitates the evaluation of ecPis-2S, 2L, ecPis-3S, and ecPis-4S, -4L as potential templates of therapeutic agents against pathogens.


Asunto(s)
Lubina , Infecciones por Cilióforos/veterinaria , Enfermedades de los Peces/genética , Proteínas de Peces/genética , Inmunidad Innata , Filogenia , Vibriosis/veterinaria , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Lubina/clasificación , Lubina/genética , Cilióforos/fisiología , Infecciones por Cilióforos/genética , Infecciones por Cilióforos/inmunología , Infecciones por Cilióforos/parasitología , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/microbiología , Enfermedades de los Peces/parasitología , Proteínas de Peces/química , Proteínas de Peces/metabolismo , Regulación de la Expresión Génica/inmunología , Especificidad de Órganos , Distribución Aleatoria , Alineación de Secuencia/veterinaria , Vibriosis/genética , Vibriosis/inmunología , Vibriosis/microbiología , Vibrio parahaemolyticus/fisiología
19.
Appl Opt ; 54(20): 6367-76, 2015 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-26193416

RESUMEN

Suspended sediments in water bodies are classified into organic and inorganic matter and have been investigated by remote-sensing technology for years. Focusing on inorganic matter, however, detailed information such as the grain size of this matter has not been provided yet. In this study, we present a new solution for estimating inorganic suspended sediments' size distribution in highly complex Case 2 waters by using a simple spectrometer sensor rather than a backscattering sensor. An experiment was carried out in the Pearl River Estuary (PRE) in the dry season to collect the remote-sensing reflectance (Rrs) and particle size distribution (PSD) of inorganic suspended sediments. Based on Mie theory, PSDs in the PRE waters were retrieved by Rrs, colored dissolved organic matter, and phytoplankton. The retrieved median diameters in 12 stations show good agreement with those of laboratory analysis at root mean square error of 2.604 µm (27.63%), bias of 1.924 µm (20.42%), and mean absolute error of 2.298 µm (24.37%). The retrieved PSDs and previous PSDs were compared, and the features of PSDs in the PRE waters were concluded.

20.
Sci Total Environ ; 918: 170637, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38316314

RESUMEN

The Arctic Ocean, as a significant carbon sink, is attracting increased attention within the scientific community. This study focused on the main marginal sea ice zone, which has been the most sensitive to environmental changes in recent decades. Using data from reanalysis, models, and on-site observations, the changes in air-sea CO2 flux (FCO2) were analyzed during the influence of Arctic cyclones (ACs) in 2021-2022. Results indicated that the passage of ACs tended to increase the average carbon sink in the main marginal ice zone, with a more pronounced effect during the cold season. During ACs, the average FCO2 could reach -6.95 mmolC m-2 d-1. This was mainly associated with the stronger and more concentrated distribution of ACs where there was lower pCO2 (air-sea gradient of CO2 partial pressure) in the cold season. Additionally, the change in FCO2 during ACs was primarily affected by the sea surface wind and sea-ice concentration in the cold season, while it was influenced by a variety of environmental factors in the warm season, including the sea surface wind, sea-ice concentration, and ecological factors.

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