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1.
Sensors (Basel) ; 23(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37112334

RESUMO

To address the issues of not accurately identifying ice types and thickness in current fiber-optic ice sensors, in this paper, we design a novel fiber-optic ice sensor based on the reflected light intensity modulation method and total reflection principle. The performance of the fiber-optic ice sensor was simulated by ray tracing. The low-temperature icing tests validated the performance of the fiber-optic ice sensor. It is shown that the ice sensor can detect different ice types and the thickness from 0.5 to 5 mm at temperatures of -5 °C, -20 °C, and -40 °C. The maximum measurement error is 0.283 mm. The proposed ice sensor provides promising applications in aircraft and wind turbine icing detection.

2.
J Environ Sci (China) ; 130: 75-84, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37032044

RESUMO

Beijing-Tianjin-Hebei and its surrounding areas (hereinafter referred to as "2+26" cities) are one of the most severe air pollution areas in China. The fine particulate matter (PM2.5) and surface ozone (O3) pollution have aroused a significant concern on the national scale. In this study, we analyzed the pollution characteristics of PM2.5 and O3 in "2+26" cities, and then estimated the health burden and economic loss before and after the implementation of the joint PM2.5-O3 control policy. During 2017-2019, PM2.5 concentration reduced by 19% while the maximum daily 8 hr average (MDA8) O3 stayed stable in "2+26" cities. Spatially, PM2.5 pollution in the south-central area and O3 pollution in the central region were more severe than anywhere else. With the reduction in PM2.5 concentration, premature deaths from PM2.5 decreased by 18% from 2017 to 2019. In contrast, premature deaths from O3 increased by 5%. Noticeably, the huge potential health benefits can be gained after the implementation of a joint PM2.5-O3 control policy. The premature deaths attributed to PM2.5 and O3 would be reduced by 91.6% and 89.1%, and the avoidable economic loss would be 60.8 billion Chinese Yuan (CNY), and 68.4 billion CNY in 2035 compared with that in 2019, respectively. Therefore, it is of significance to implement the joint PM2.5-O3 control policy for improving public health and economic development.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Humanos , Pequim , Poluentes Atmosféricos/análise , Melhoria de Qualidade , Monitoramento Ambiental , Poluição do Ar/prevenção & controle , Poluição do Ar/análise , Material Particulado/análise , China , Cidades , Políticas
3.
BMC Med ; 20(1): 321, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36184642

RESUMO

BACKGROUND: Strategies to improve activity of immune checkpoint inhibitors for triple-negative breast cancer (TNBC) are needed. Preclinical studies showed that antiangiogenic agents and poly (ADP-ribose) polymerase (PARP) inhibitors might sensitize tumors to immunotherapy. Here, we investigated the tolerability, safety, and preliminary antitumor activity of camrelizumab, an anti-PD-1 antibody, in combination with apatinib, a vascular endothelial growth factor receptor-2 inhibitor, and fuzuloparib, a PARP inhibitor, in patients with recurrent or metastatic TNBC. METHODS: This phase Ib study included a dose-finding part and a dose-expansion part. In the dose-finding part, a 3 + 3 dose escalation scheme was introduced. Patients were given camrelizumab (200 mg every 2 weeks) plus apatinib (375 mg or 500 mg once daily) and fuzuloparib (starting dose 100 mg twice daily) every 28-day cycle. After evaluation of the tolerability and safety of the dosing regimens, a clinical recommended dose was determined for the dose-expansion part. The primary endpoint was dose-limiting toxicity (DLT). RESULTS: A total of 32 patients were enrolled. Three patients received camrelizumab 200 mg + apatinib 375 mg + fuzuloparib 100 mg, and 29 received camrelizumab 200 mg + apatinib 500 mg + fuzuloparib 100 mg (clinical recommended dose). No DLTs were observed in either group. The most common grade ≥ 3 treatment-related adverse events were decreased white blood cell count (20.7%), hypertension (13.8%), decreased neutrophil count (10.3%), and increased aspartate aminotransferase (10.3%). Two patients discontinued study treatment due to immune-mediated hepatitis (n = 1) and anemia, decreased platelet count, decreased white blood cell count, increased alanine aminotransferase, increased aspartate aminotransferase, and increased γ-glutamyltransferase (n = 1). One patient died of unknown cause. Two (6.9% [95% CI, 0.9-22.8]) of 29 patients with camrelizumab 200 mg + apatinib 500 mg + fuzuloparib 100 mg had objective response. The disease control rate was 62.1% (95% CI, 42.3-79.3). The median progression-free survival was 5.2 months (95% CI, 3.6-7.3), and the 12-month overall survival rate was 64.2% (95% CI, 19.0-88.8). CONCLUSIONS: Combination of camrelizumab plus apatinib and fuzuloparib showed manageable safety profile and preliminary antitumor activity in patients with recurrent or metastatic TNBC. TRIAL REGISTRATION: ClinicalTrials.gov NCT03945604 (May 10, 2019).


Assuntos
Neoplasias de Mama Triplo Negativas , Difosfato de Adenosina/uso terapêutico , Alanina Transaminase/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Aspartato Aminotransferases/uso terapêutico , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Piridinas , Ribose/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/uso terapêutico , gama-Glutamiltransferase/uso terapêutico
4.
Br J Clin Pharmacol ; 88(7): 3307-3320, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35112382

RESUMO

AIM: This trial (NCT04013048) investigated the metabolite profiles, mass balance and pharmacokinetics of fuzuloparib, a novel poly (ADP-ribose) polymerase inhibitor, in subjects with advanced solid cancers. METHODS: A single dose of 150 mg [14 C]fuzuloparib was administered to five subjects with advanced solid cancers. Blood, urine and faecal samples were collected, analysed for radioactivity and unchanged fuzuloparib, and profiled for metabolites. The safety of the medicine was assessed during the study. RESULTS: The maximum concentrations (Cmax ) of the total radioactivity (TRA) and unchanged fuzuloparib in plasma were 5.39 µg eq./mL and 4.19 µg/mL, respectively, at approximately 4 hours post dose. The exposure (AUC0-t ) of fuzuloparib accounted for 70.7% of the TRA in plasma, and no single metabolite was observed accounting for more than 10% of the plasma TRA. The recovery of TRA in excreta was 103.3 ± 3.8% in 288 hours, including 59.1 ± 9.9% in urine and 44.2 ± 10.8% in faeces. Sixteen metabolites of fuzuloparib were identified, including mono-oxidation (M1), hydrogenation (M2), di-oxidation (M3), trioxidation (M4), glucuronidation (M5, M7, M8) and de-ethylation (M6) products, and there was no specific binding between these metabolites and blood cells. Aliphatic hydroxylated fuzuloparib (M1-1) was the primary metabolite in the excreta, accounting for more than 40% of the dose for subjects. There were no serious adverse events observed in the study. CONCLUSION: Fuzuloparib was widely metabolized and excreted completely through urine and faeces in subjects with advanced solid cancer. Unchanged fuzuloparib was indicated to be the primary drug-related compound in circulation. [14 C]fuzuloparib was well-tolerated at the study dose.


Assuntos
Antineoplásicos , Neoplasias , Difosfato de Adenosina/análise , Administração Oral , Antineoplásicos/efeitos adversos , Fezes/química , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/efeitos adversos , Inibidores de Poli(ADP-Ribose) Polimerases/análise , Ribose/análise
5.
J Clin Gastroenterol ; 56(5): e273-e282, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35324486

RESUMO

BACKGROUND: The spatial-temporal distribution of Helicobacter pylori infection in China is poorly understood. We aimed to study the spatial-temporal distribution of H. pylori infection in Chinese mainland and to explore its influencing factors. MATERIALS AND METHODS: We searched the relevant literature from 2001 to 2021 and applied meta-analysis to obtain the pooled prevalence estimates of all studies and subgroups. Then, we used the pooled prevalence as the dependent variable for the following analysis, including time series analysis, statistical mapping, spatial autocorrelation analysis, and influencing factor analysis based on generalized additive model and panel data model. RESULTS: A total of 726 articles and 3,407,392 people were included. The pooled prevalence was 43.7% (95% confidence interval: 42.7%-44.8%). The prevalence decreased in the past 20 years, with high in the eastern and western regions and low in the central region. Qinghai Tibet Plateau and Guizhou Plateau were the high incidence areas of this disease. The intake of vegetable oil, aquatic products, meat, milk, per capita gross domestic product, and annual average humidity were significantly correlated with H. pylori. CONCLUSIONS: The prevalence of H. pylori is decreasing in Chinese mainland, but still high in underdeveloped areas. Appropriate strategies for the prevention need greater attention.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , China/epidemiologia , Infecções por Helicobacter/epidemiologia , Humanos , Incidência , Prevalência
6.
Anal Bioanal Chem ; 414(29-30): 8263-8276, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36201045

RESUMO

Dendritic organic molecular gels are a promising class of three-dimensional network compounds. Here, we have synthesized a new type of dendritic organic molecular gel stationary phase (SiO2-G3) by using benzyl alcohol as raw material and dimethyl 5-hydroxyisophthalate as growth unit to synthesize a third-generation organic molecular gel G3, which grafted onto the silica surface by cyanogen chloride (CC). The developed stationary phase not only exhibits high molecular shape selectivity but also has a RPLC/HILIC/IEC mixed-mode characteristic for HPLC due to the ordered structure, the multiple strong π-π stacking interactions and the introduction of a hydrophilic triazine fraction during the grafting process. Compared with a commercial C18 column, the developed column exhibited flexible selectivity, enhanced separation performance and excellent separation of monosubstituted benzene, polycyclic aromatic hydrocarbons (PAHs), positional isomers, nucleosides and nucleobases, benzoic acid and aniline compounds. In addition, the new column provided baseline separation of polycyclic aromatic hydrocarbon contaminants in Yellow River water, verifying its potential for application in the analysis of real samples.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Dióxido de Silício , Dióxido de Silício/química , Cromatografia Líquida , Interações Hidrofóbicas e Hidrofílicas , Cromatografia Líquida de Alta Pressão/métodos , Géis , Hidrocarbonetos Policíclicos Aromáticos/análise
7.
Environ Res ; 208: 112671, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-34999023

RESUMO

Hebei Province, located in the North China Plain (NCP) and encircling Beijing and Tianjin, has been suffering from severe air pollution. The monthly average fine particulate matter (PM2.5) concentration was up to 276 µg/m3 in Hebei Province, which adversely affects human health. However, few studies evaluated the coordinated health impact of exposure to PM (PM2.5 and PM10) and other key air pollutants (SO2, NO2, CO, and surface ozone (O3)). In this study, we systematically analyzed the health risks (both mortality and morbidity) due to multiple air pollutants exposures in Hebei Province. The economic loss associated with these health consequences was estimated using the value of statistical life (VSL) and cost of illness (COI) methods. Our results show the health burden and economic loss attributable to multiple ambient air pollutants exposures in Hebei Province is substantial. In 2017, the total premature mortality from multiple air pollutants exposures in Hebei Province was 69,833 (95% CI: 55,549-83,028), which was 2.9 times higher than that of the Pearl River Delta region (PRD). Most of the potential economic loss (79.65%) was attributable to premature mortality from air pollution. The total economic loss due to the health consequences of multiple air pollutants exposures was 175.16 (95% CI: 134.61-224.61) billion Chinese Yuan (CNY), which was 4.92% of Hebei Province's annual gross domestic product (GDP). Thus, the adverse health effects and economic loss caused by exposure to multiple air pollutants should be seriously taken into consideration. To alleviate these damages, Hebei's government ought to establish more stringent measures and regulations to better control air pollution.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Material Particulado , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , China/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais , Humanos , Material Particulado/análise , Material Particulado/toxicidade
8.
Opt Express ; 29(9): 13542-13551, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33985087

RESUMO

Optical metalens has been attracting more and more attention in recent years. To date, it is still difficult to simultaneously achieve wide field and broadband imaging in the visible region, which is very important in many applications, such as cameras, microscopy, and other imaging devices. In this paper, we design a double-layer metalens to achieve achromatic imaging over a field of view (FOV) of 60° in the visible light range of 470 nm to 650 nm, and its performance is verified by numerical simulations. The numerical aperture (NA) of the metalens is 0.61 and the average focusing efficiency is > 50% at normal incidence. The metalens has an additional advantage of polarization insensitivity.

9.
Proc Biol Sci ; 287(1937): 20202010, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33081614

RESUMO

The spread of infection from reservoir host populations is a key mechanism for disease emergence and extinction risk and is a management concern for salmon aquaculture and fisheries. Using a quantitative environmental DNA methodology, we assessed pathogen environmental DNA in relation to salmon farms in coastal British Columbia, Canada, by testing for 39 species of salmon pathogens (viral, bacterial, and eukaryotic) in 134 marine environmental samples at 58 salmon farm sites (both active and inactive) over 3 years. Environmental DNA from 22 pathogen species was detected 496 times and species varied in their occurrence among years and sites, likely reflecting variation in environmental factors, other native host species, and strength of association with domesticated Atlantic salmon. Overall, we found that the probability of detecting pathogen environmental DNA (eDNA) was 2.72 (95% CI: 1.48, 5.02) times higher at active versus inactive salmon farm sites and 1.76 (95% CI: 1.28, 2.42) times higher per standard deviation increase in domesticated Atlantic salmon eDNA concentration at a site. If the distribution of pathogen eDNA accurately reflects the distribution of viable pathogens, our findings suggest that salmon farms serve as a potential reservoir for a number of infectious agents; thereby elevating the risk of exposure for wild salmon and other fish species that share the marine environment.


Assuntos
Aquicultura , DNA Ambiental , Animais , Colúmbia Britânica , Monitoramento Ambiental , Fazendas , Doenças dos Peixes , Pesqueiros , Salmo salar , Microbiologia da Água
10.
J Exp Biol ; 223(Pt 12)2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32345705

RESUMO

We examined cardiac pacemaker rate resetting in rainbow trout following a reciprocal temperature transfer. In the original experiment, performed in winter, 4°C-acclimated fish transferred to 12°C reset intrinsic heart rate after just 1 h (from 56.8±1.2 to 50.8±1.5 beats min-1); 12°C-acclimated fish transferred to 4°C reset intrinsic heart rate after 8 h (from 33.4±0.7 to 37.7±1.2 beats min-1). However, in a replicate experiment, performed in the summer using a different brood year, intrinsic heart rate was not reset, even after 10 weeks at a new temperature. Using this serendipitous opportunity, we compared mRNA expression changes of a suite of proteins in sinoatrial node (SAN), atrial and ventricular tissues after both 1 h and longer than 3 weeks for both experimental acclimation groups to identify those changes only associated with pacemaker rate resetting. Of the changes in mRNA expression occurring after more than 3 weeks of warm acclimation and associated with pacemaker rate resetting, we observed downregulation of NKA α1c in the atrium and ventricle, and upregulation of HCN1 in the ventricle. However, in the SAN there were no mRNA expression changes unique to the fish with pacemaker rate resetting after either 1 h or 3 weeks of warm acclimation. Thus, despite identifying changes in mRNA expression of contractile cardiac tissues, there was an absence of changes in mRNA expression directly involved with the initial, rapid pacemaker rate resetting with warm acclimation. Importantly, pacemaker rate resetting with thermal acclimation does not always occur in rainbow trout.


Assuntos
Oncorhynchus mykiss , Aclimatação , Animais , Frequência Cardíaca , Ventrículos do Coração , Temperatura
11.
J Fish Dis ; 43(7): 729-746, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32364277

RESUMO

Wild fish are confronting changing pathogen dynamics arising from anthropogenic disturbance and climate change. Pathogens can influence animal behaviour and life histories, yet there are little such data from fish in the high north where pathogen dynamics may differ from comparatively southern regions. We aimed to compare the pathogen communities of 160 wild anadromous brown trout in two fjords in northern Norway and to determine whether pathogens influenced area use or return to spawn. Application of high-throughput qPCR detected 11 of the 46 pathogens screened for; most frequently encountered were Ichthyobodo spp., Flavobacterium psychrophilum and Candidatus Branchiomonas cysticola. The rate of returning to freshwater during the spawning season was significantly lower for the Skjerstadfjord fish. Piscichlamydia salmonis and F. psychrophilum were indicator species for the Skjerstadfjord and pathogen communities in the two fjords differed according to perMANOVA. Individual length, Fulton's condition factor and the time between first and last detection of the fish were not related to the presence of pathogens ordinated using non-metric multidimensional scaling (NMDS). However, there was evidence that pathogen load was correlated with the expression of smoltification genes, which are upregulated by salmonids in freshwater. Correspondingly, percentage of time in freshwater after release was longer for fish with greater pathogen burdens.


Assuntos
Migração Animal , Ecossistema , Doenças dos Peixes/microbiologia , Truta , Animais , Carga Bacteriana , Doenças dos Peixes/parasitologia , Doenças dos Peixes/virologia , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Noruega , Reação em Cadeia da Polimerase/veterinária , Carga Viral
12.
J Exp Biol ; 222(Pt 13)2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31209112

RESUMO

An organism's ability to respond effectively to environmental change is critical to its survival. Yet, life stage and overall condition can dictate tolerance thresholds to heightened environmental stressors, such that stress may not be equally felt across individuals and at all times. Also, the transcriptional responses induced by environmental changes can reflect both generalized responses as well as others that are highly specific to the type of change being experienced. Thus, if transcriptional biomarkers specific to a stressor, even under multi-stressor conditions, can be identified, the biomarkers could then be applied in natural environments to determine when and where an individual experiences such a stressor. Here, we experimentally challenged juvenile Chinook salmon (Oncorhynchus tshawytscha) to validate candidate gill gene expression biomarkers. A sophisticated experimental design manipulated salinity (freshwater, brackish water and seawater), temperature (10, 14 and 18°C) and dissolved oxygen (normoxia and hypoxia) in all 18 possible combinations for 6 days using separate trials for three smolt statuses (pre-smolt, smolt and de-smolt). In addition, changes in juvenile behaviour, plasma variables, gill Na+/K+-ATPase activity, body size, body morphology and skin pigmentation supplemented the gene expression responses. We identified biomarkers specific to salinity and temperature that transcended the multiple stressors, smolt status and mortality (live, dead and moribund). Similar biomarkers for dissolved oxygen were not identified. This work demonstrates the unique power of gene expression biomarkers to identify a specific stressor even under multi-stressor conditions, and we discuss our next steps for hypoxia biomarkers using an RNA-seq study.


Assuntos
Expressão Gênica/fisiologia , Marcadores Genéticos/fisiologia , Salinidade , Salmão/fisiologia , Temperatura , Animais , Características de História de Vida , Oxigênio/química , Oxigênio/metabolismo , Salmão/genética
13.
BMC Genomics ; 19(1): 749, 2018 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-30326831

RESUMO

BACKGROUND: Pacific salmon (Oncorhynchus spp.) serve as good biological indicators of the breadth of climate warming effects on fish because their anadromous life cycle exposes them to environmental challenges in both marine and freshwater environments. Our study sought to mine the extensive functional genomic studies in fishes to identify robust thermally-responsive biomarkers that could monitor molecular physiological signatures of chronic thermal stress in fish using non-lethal sampling of gill tissue. RESULTS: Candidate thermal stress biomarkers for gill tissue were identified using comparisons among microarray datasets produced in the Molecular Genetics Laboratory, Pacific Biological Station, Nanaimo, BC, six external, published microarray studies on chronic and acute temperature stress in salmon, and a comparison of significant genes across published studies in multiple fishes using deep literature mining. Eighty-two microarray features related to 39 unique gene IDs were selected as candidate chronic thermal stress biomarkers. Most of these genes were identified both in the meta-analysis of salmon microarray data and in the literature mining for thermal stress markers in salmonids and other fishes. Quantitative reverse transcription PCR (qRT-PCR) assays for 32 unique genes with good efficiencies across salmon species were developed, and their activity in response to thermally challenged sockeye salmon (O. nerka) and Chinook salmon (O. tshawytscha) (cool, 13-14 °C and warm temperatures 18-19 °C) over 5-7 days was assessed. Eight genes, including two transcripts of each SERPINH1 and HSP90AA1, FKBP10, MAP3K14, SFRS2, and EEF2 showed strong and robust chronic temperature stress response consistently in the discovery analysis and both sockeye and Chinook salmon validation studies. CONCLUSIONS: The results of both discovery analysis and gene expression showed that a panel of genes involved in chaperoning and protein rescue, oxidative stress, and protein biosynthesis were differentially activated in gill tissue of Pacific salmon in response to elevated temperatures. While individually, some of these biomarkers may also respond to other stressors or biological processes, when expressed in concert, we argue that a biomarker panel comprised of some or all of these genes could provide a reliable means to specifically detect thermal stress in field-caught salmon.


Assuntos
Marcadores Genéticos/genética , Resposta ao Choque Térmico/genética , Salmonidae/genética , Salmonidae/fisiologia , Animais , Perfilação da Expressão Gênica , Perfil Genético , Brânquias/metabolismo
14.
Biomed Microdevices ; 20(2): 36, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29651562

RESUMO

Enterococcus faecalis(E. faecalis) is a common microorganism could be isolated from the infected canals, especially in the case of refractory apical periodontitis. Due to its ability to invade the dentinal tubules and highly resistant to antimicrobial strategies, the thorough debridement of E.faecalis is hard to achieve. And that may be one of the reasons to cause reinfection and therapeutic failure. According to the anatomy of dentinal tubules published before and the results of our team previous work, we designed six types of microtubes with different sizes. By using the method of centrifugation and incubation, a standard infected model mimicking dentinal tubules was established. Sodium hypochlorite (NaClO) is the most popular irrigant applied in root canal treatment. We used three different concentrations with four distinct irrigation duration to observe the antibacterial process of E. faecalis colonies within microtubes dynamically. We concluded that the role of NaClO in the microtubes is concentration dependent and duration dependent. And the interpretation of the results has a certain reference value for clinicians.


Assuntos
Técnicas de Cultura de Células/instrumentação , Enterococcus faecalis/química , Enterococcus faecalis/citologia , Microtecnologia/instrumentação , Hipoclorito de Sódio/química , Desenho de Equipamento , Solubilidade
15.
Opt Express ; 24(2): A408-13, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26832592

RESUMO

We proposed a Fourier-series based periodic nanostructure(FSPN) for light trapping in thin film silicon solar cells. By globally optimizing the Fourier coefficients across entire silicon absorption spectrum, we obtained a FSPN structure with short circuit current density greater than 24 mA/cm(2) for a 1µm real silicon absorption layer. The spectral analysis shows at normal incidence the FSPN exhibits a collection effect of periodic gratings and performs over 84.6% better than random texture. The angular analysis shows that the FSPN outperforms grating and random textures within 70 °.

16.
Drug Metab Dispos ; 43(3): 411-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25547867

RESUMO

Brain metastasis (BM) is increasingly diagnosed in Her2 positive breast cancer (BC) patients. Lack of effective treatment to breast cancer brain metastases (BCBMs) is probably due to inability of the current therapeutic agents to cross the blood-brain barrier. The central nervous system (CNS) response rate in BCBM patients was reported to improve from 2.6%-6% (lapatinib) to 20%-65% (lapatinib in combination with capecitabine). Lapatinib is a poor brain penetrant. In this study, we evaluated the CNS penetration of capecitabine and hoped to interpret the mechanism of the improved CNS response from the pharmacokinetic (PK) perspective. Capecitabine does not have antiproliferative activity and 5-fluorouracil (5-FU) is the active metabolite. Capecitabine was orally administered to mouse returning an unbound brain-to-blood ratio (Kp,uu,brain) at 0.13 and cerebrospinal fluid (CSF)-to-unbound blood ratio (Kp,uu,CSF) at 0.29 for 5-FU. Neither free brain nor CSF concentration of 5-FU can achieve antiproliferative concentration for 50% of maximal inhibition of cell proliferation of 4.57 µM. BCBM mice were treated with capecitabine monotherapy or in combination with lapatinib. The Kp,uu,brain value of 5-FU increased to 0.17 in the brain tumor in the presence of lapatinib, which is still far below unity. The calculated free concentration of 5-FU and lapatinib in the brain tumor did not reach the antiproliferative potency and neither treatment showed antitumor activity in the BCBM mice. The CNS penetration of 5-FU in human was predicted based on the penetration in preclinical brain tumor, CSF, and human PK and the predicted free CNS concentration was below the antiproliferative potency. These results suggest that CNS penetration of 5-FU and lapatinib are not desirable and development of a true CNS penetrable therapeutic agent will further improve the response rate for BCBM.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias da Mama/patologia , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Animais , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/secundário , Capecitabina , Proliferação de Células/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Desoxicitidina/administração & dosagem , Desoxicitidina/metabolismo , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/metabolismo , Humanos , Lapatinib , Camundongos , Camundongos Endogâmicos BALB C , Quinazolinas/administração & dosagem , Receptor ErbB-2/metabolismo
17.
Mol Ecol ; 23(23): 5803-15, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25354752

RESUMO

We present the first data to link physiological responses and pathogen presence with subsequent fate during migration of wild salmonid smolts. We tagged and non-lethally sampled gill tissue from sockeye salmon (Oncorhynchus nerka) smolts as they left their nursery lake (Chilko Lake, BC, Canada) to compare gene expression profiles and freshwater pathogen loads with migration success over the first ~1150 km of their migration to the North Pacific Ocean using acoustic telemetry. Fifteen per cent of smolts were never detected again after release, and these fish had gene expression profiles consistent with an immune response to one or more viral pathogens compared with fish that survived their freshwater migration. Among the significantly upregulated genes of the fish that were never detected postrelease were MX (interferon-induced GTP-binding protein Mx) and STAT1 (signal transducer and activator of transcription 1-alpha/beta), which are characteristic of a type I interferon response to viral pathogens. The most commonly detected pathogen in the smolts leaving the nursery lake was infectious haematopoietic necrosis virus (IHNV). Collectively, these data show that some of the fish assumed to have died after leaving the nursery lake appeared to be responding to one or more viral pathogens and had elevated stress levels that could have contributed to some of the mortality shortly after release. We present the first evidence that changes in gene expression may be predictive of some of the freshwater migration mortality in wild salmonid smolts.


Assuntos
Migração Animal , Proteínas de Peixes/genética , Salmão/genética , Salmão/virologia , Animais , Colúmbia Britânica , Conservação dos Recursos Naturais/métodos , Proteínas de Peixes/imunologia , Água Doce , Brânquias , Vírus da Necrose Hematopoética Infecciosa/isolamento & purificação , Oceano Pacífico , Rios , Salmão/imunologia , Telemetria , Transcriptoma
18.
ScientificWorldJournal ; 2014: 121245, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25197688

RESUMO

The aim of this paper is to develop an effective method for solving bimatrix games with payoffs of intuitionistic fuzzy value. Firstly, bimatrix game model with intuitionistic fuzzy payoffs (IFPBiG) was put forward. Secondly, two kinds of nonlinear programming algorithms were discussed with the Nash equilibrium of IFPBiG. Thirdly, Nash equilibrium of the algorithm was proved by the fixed point theory and the algorithm was simplified by linear programming methods. Finally, an example was solved through Matlab; it showed the validity, applicability, and superiority.


Assuntos
Algoritmos , Teoria dos Jogos , Jogos Experimentais , Intuição , Modelos Teóricos , Recompensa , Simulação por Computador , Lógica Fuzzy , Humanos
19.
J Chromatogr A ; 1733: 465228, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39163701

RESUMO

In this study, using chiral L-lysine as the molecular skeleton, three kinds of L-lysine-derived gelators (GBLB, GBLF and GFLF) were synthesized and then bonded to the surface of silica matrix (5 µm) by amide condensation to prepare a series of multifunctional chromatography stationary phases (GBLB-SiO2, GBLF-SiO2, and GFLF-SiO2) were prepared. The L-lysine-derived gelators not only possess chiral recognition ability, but also can spontaneously form oriented and ordered network structures in liquid medium through the interaction of non-covalent bonding forces such as hydrogen bonding, π-π stacking, and van der Waals forces. The comprehensive effect of multiple weak interaction sites enhances the molecular recognition ability and further improves the separation diversity of different types of compounds on stationary phases. The separation and evaluation of chiral compounds showed that benzoin, 1-phenyl-ethanol, 1-phenyl-propanol and 6-hydroxyflavanone could be separated in normal phase mode (NPLC). The separation of different types of non-chiral compounds, such as sulfonamides, nucleosides, nucleobases, polycyclic aromatic hydrocarbons (PAHs), anilines, and aromatic acids, were achieved in hydrophilic interaction/reversed-phase/ion-exchange mode (HILIC/RPLC/IEC), and the separation of polarized compounds could be performed under the condition of ultrapure water as the mobile phase, which has the typical retention characteristics of per aqueous liquid chromatography (PALC). The effects of organic solvent content, temperature, pH value, and buffer salt concentration on the retention and separation performance of the column were investigated. Comparison of the three prepared columns showed that the separation performance (such as aromatic selectivity) could be improved by increasing the types of functional groups on the surface of the stationary phase and the number of aromatic groups. In a word, the prepared stationary phase have multiple retention properties, can simultaneously separate chiral compounds and various types of achiral compounds. This work provides an idea for developing multifunctional liquid chromatography stationary phase materials, and further expands the application of gelators in separation science.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Lisina , Dióxido de Silício , Estereoisomerismo , Lisina/química , Dióxido de Silício/química , Cromatografia Líquida de Alta Pressão/métodos
20.
J Mol Model ; 30(2): 56, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38294566

RESUMO

CONTEXT: Two-dimensional materials are a new and promising research field in materials science. This is mainly attributed to their unique photoelectric and chemical properties. In addition to possessing unique optoelectronic and chemical properties, two-dimensional materials also have important application prospects in the field of field-effect devices. Based on density functional theory, the effects of uniaxial strain and equibiaxial strain on the mechanical properties, electronic structure, and optical properties of monolayer h-BN were studied using first principles. The results indicate that compressive strain has a significant impact on the stability of monolayer h-BN. The band gap width of monolayer h-BN decreases with increasing strain, and the optical properties of monolayer h-BN exhibit a relative trend under tensile and compressive strains. The influence of biaxial strain on the mechanical properties, electronic structure, and optical properties of monolayer h-BN is greater than that of uniaxial strain. METHODS: All the calculations were done by the VASP software based on density functional theory. The interaction between atomic nuclei and electrons is described by the projected added wave pseudopotential (PAW), using the generalized gradient approximation (GGA) to exchange the Perdew-Burke-Ernzerhof (PBE) of the functional. To avoid interlayer interactions, a 15-Å vacuum layer was set up. The Brillouin zone selects the Monkhorst-Pack method to generate 9 × 9 × 1 of k-point grid, the cut off energy is set to 500 eV, the energy convergence standard of the system is 1 × 10-5 eV, and the interaction force between atoms is 0.01 eV/Å.

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