Pulsed‐laser ablation in liquid (PLAL) is a green synthesis technique to obtain semiconductor nanomaterials in colloidal form. Herein, cadmium sulfide (CdS) nanoparticles were synthesized by the ...pulsed‐laser ablation of a CdS target in different liquid media by using λ=532 and 1064 nm outputs from a pulsed (10 ns, 10 Hz) Nd:YAG laser at different ablation fluence values. The morphology, structure, crystalline phase, elemental composition, optical, and luminescent properties of CdS nanomaterials were analyzed by using transmission electron microscopy (TEM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), UV/Vis absorption spectroscopy, and fluorescence spectroscopy. By changing the liquid medium and ablation wavelength, CdS nanoparticles with different morphology and size were formed, as demonstrated by using TEM analysis. The crystallinity and chemical states of the ablation products were confirmed by using XRD and XPS analyses. The optical bandgap of the CdS nanoparticles was dependent on the ablation wavelength and the fluence. These nanocolloids presented different green emissions, which implied the presence of several emission centers. CdS nanocolloids in distilled water catalyzed the photocatalytic decay of methylene blue dye under light irradiation from a solar simulator.
CdS nanocolloids: CdS nanoparticles with different morphologies and optical and luminescent properties are formed by pulsed‐laser ablation in liquid. The ablation wavelength, liquid medium, and fluence are decisive in tuning the morphology, size, and properties.
BackgroundImmune checkpoint inhibitors (ICI) have successfully improved the survival in metastatic triple-negative breast cancer (mTNBC), but benefit is limited to PD-L1 positive tumors. Metastatic ...tumors are notorious for deficient immune cell infiltration which may limit responses to ICI in mTNBC. However, the underlying mechanisms for the weak immunogenicity of the metastatic tumor immune microenvironment (TIME) and related poor ICI responses are still not well understood. The current study was designed to investigate the evolution of the TIME between paired primary and metastatic TNBCs.MethodsWe analyzed spatial distribution of 37 key immune regulators using the NanoString digital spatial profiling (DSP) platform. 452 regions of interests (ROIs) from 33 primary tumors (PT) and 29 metastatic tumors (MT) including 28 paired specimens, were selected based on CD45+ immune hotspots, and the protein expression levels of the key immune regulators were quantified within pan-cytokeratin (panCK) and CD45 masked regions, respectively. In parallel, we examined the clonality of tumor infiltrating B cell receptors by reconstructing the immune repertoire from bulk RNA-seq data.ResultsUsing the DSP platform, reduced immune infiltration (e.g., CD3 and CD20) in both panCK and CD45 masked regions of MT was confirmed, while CD8A and CD11c (padj = 2.8×10-7 and 2.1×10-6) expression was only observed in panCK masked regions of MT compared with PT. In support of the lower CD20 counts in MT, immune repertoire analysis revealed B cell receptor (BCR) repertoire diversity (represented by Gini index) was substantially lower in MT than PT (p = 0.041) suggesting that the ability of B cells to recognize a wide variety of tumor antigens in MT is greatly reduced in contrast to PT. Besides, we identified a significant shift in myeloid composition between PT and MT as evidenced by increased CD68 signal (padj = 5.8×10-4) in CD45 masked regions of MT. Within MT, PD-L1 signal was substantially higher (padj = 0.030) in CD45 masked regions only, while PD1 counts were lower (padj = 0.035) in panCK masked regions. This suggests the limited responses to ICI for MT may stem from relatively low expression of activated and targetable T cell subsets in MT islands.ConclusionsThrough comprehensive analysis of the TIME spatial organization within paired PT and MT, a significant reduction in dendritic cell/macrophage ratios (CD11c/CD68), reduced tumor localized T cell activation (CD8, PD1, PD-L1), and reduced B cell diversity (BCR clonality) are key features of the reduced immunogenicity of the metastatic TIME in TNBC.AcknowledgementsThis work is supported through an NCI K-12 Career Development Award (K12CA001727, PI Joanne Mortimer), and the National Institutes of Health (P30CA033572). Research reported in this publication included work performed in the Pathology Research Services Core, Biostatistics and Mathematical Modeling Core, Integrative Genomics Core, and Bioinformatics Core supported by the National Cancer Institute of the National Institutes of Health under award number P30CA033572.Ethics ApprovalPaired TNBC specimens were identified through a City of Hope IRB-approved retrospective protocol (IRB 07047) via the City of Hope (COH) Biorepository from patients with breast cancer treated at COH from 2002 to 2015. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent was obtained from all of the participants of this study.
•We devised a brief 8-item measure of COVID-19 organizational support (COVID-OS).•The measure has three dimensions: work support, personal support, and risk support.•All three dimensions demonstrated ...criterion validity of predicting anxiety and satisfaction.•Work support discriminated healthcare workers with minimal and mild anxiety.•Personal support discriminated between people with mild and moderate anxiety.
During the COVID-19 pandemic, healthcare workers are facing high workloads with resource constraints and risk of virus exposure, and healthcare organizations need to support their healthcare workers to reduce their anxiety. Based on a recent 8-point framework of COVID-19 specific organization support, we devised a measure of COVID-19 Organizational Support (COVID-OS). We tested the new measure with 712 healthcare workers in Bolivia, Ecuador, and Peru and found the new measure formed three factors to predict healthcare workers’ anxiety and life satisfaction during the COVID-19 pandemic. We call for further studies to test COVID-OS in other countries and settings.
Plastic materials are widely used in food packaging applications; however, there is increased concern because of the possible release of undesirable components into foodstuffs. Migration of plastic ...constituents not only has the potential to affect product quality but also constitutes a risk to consumer health. In order to check the safety of food contact materials, analytical methodologies to identify potential migrants are required. In the first part of this work, a GC/MS screening method was developed for the identification of components from plastic packaging materials including intentionally and “non-intentionally added substances” (NIAS) as potential migrants. In the second part of this study, the presence of seven compounds (bis (2-ethylhexyl) phthalate (DEHP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), dibutyl phthalate (DBP), butylated hydroxytoluene (BHT), acetyl tributyl citrate (ATBC), benzophenone (BP)) previously identified in packaging materials were investigated in food products (corn and potatoes snacks, cookies, and cakes). For this purpose, a suitable extraction method was developed and quantification was performed using GC-MS. The developed method was validated in terms of linearity, recovery, repeatability, and limits of detection and quantification. The spiked recoveries varied between 82.7 and 116.1%, and relative standard deviation (RSD) was in the range of 2.22–15.9%. The plasticizer ATBC was the most detected compound (94% samples), followed by DEP (65%), DEHP (47%), BP (44%), DBP (35%), DIBP (21%), and BHT (12%). Regarding phthalates, DEP and DEHP were the most frequently detected compounds in concentrations up to 1.44 μg g
−1
. In some samples, only DBP exceeded the European SML of 0.3 mg kg
−1
established in Regulation 10/2011.
Graphical abstract
Chemical migration from plastic packaging into food
The clustered regularly interspaced short palindromic repeats (CRISPR) system–associated Cas9 endonuclease is a molecular tool that enables specific sequence editing with high efficiency. In this ...study, we have explored the use of CRISPR/Cas9 system for the engineering of baculovirus. We have shown that the delivering of Cas9‐single guide RNA ribonucleoprotein (RNP) complex with or without DNA repair template into Sf21 insect cells through lipofection might be efficient to produce knockouts as well as knock‐ins into the baculovirus. To evaluate potential application of our CRISPR/Cas9 method to improve baculovirus as protein expression vector and as biopesticide, we attempted to knockout several genes from a recombinant AcMNPV form used in the baculovirus expression system as well as in a natural occurring viral isolate from the same virus. We have additionally confirmed the adaptation of this methodology for the generation of viral knock‐ins in specific regions of the viral genome. Analysis of the generated mutants revealed that the editing efficiency and the type of changes was variable but relatively high. Depending on the targeted gene, the editing rate ranged from 10% to 40%. This study established the first report revealing the potential of CRISPR/Cas9 for genome editing in baculovirus, contributing to the engineering of baculovirus as a protein expression vector as well as a biological control agent.
Baculoviruses are insect viruses widely used as biopesticide as well as versatile and powerful vector for recombinant protein expression. The authors have developed a CRISPR/Cas9‐assisted method to edit the baculovirus genomes for the improvement of their properties as biopesticide and as protein expression vector.
Food Contamination by Packaging Quiros, Ana Rodriguez Bernaldo de; Cardama, Antia Lestido; Sendon, Raquel ...
2019, 2019-08-05
eBook
The migration of substances from packaging to food is a matter of concern for the food safety authorities, and packaging materials constitute a potential source of contaminants to which the consumer ...will be exposed to through their diet. A huge variety of substances can be present in packaging materials, which could consequently migrate into food and represent a risk to consumer health. Food Contamination by Packaging provides an overview of the main packaging contaminants including Bisphenol A, melamine, phthalates, alternative plasticisers, photoinitiators, perfluorochemicals, saturated and aromatic hydrocarbons (mineral oil saturated hydrocarbons and mineral oil aromatic hydrocarbons) from mineral oils, other bisphenol-related compounds, nanoparticles, primary aromatic amines and nonintentionally added substances. The analytical techniques used for their determination are reviewed. This book will be of interest to students and researchers in universities and research institutions associated with food packaging and, in general, to the food safety sector.
During the coronavirus disease (COVID-19) pandemic, social media platforms have become active sites for the dissemination of conspiracy theories that provide alternative explanations of the cause of ...the pandemic, such as secret plots by powerful and malicious groups. However, the association of individuals' beliefs in conspiracy theories about COVID-19 with mental health and well-being issues has not been investigated. This association creates an assessable channel to identify and provide assistance to people with mental health and well-being issues during the pandemic.
Our aim was to provide the first evidence that belief in conspiracy theories regarding the COVID-19 pandemic is a predictor of the mental health and well-being of health care workers.
We conducted a survey of 252 health care workers in Ecuador from April 10 to May 2, 2020. We analyzed the data regarding distress and anxiety caseness with logistic regression and the data regarding life and job satisfaction with linear regression.
Among the 252 sampled health care workers in Ecuador, 61 (24.2%) believed that the virus was developed intentionally in a lab; 82 (32.5%) experienced psychological distress, and 71 (28.2%) had anxiety disorder. Compared to health care workers who were not sure where the virus originated, those who believed the virus was developed intentionally in a lab were more likely to report psychological distress and anxiety disorder and to have lower levels of job satisfaction and life satisfaction.
This paper identifies belief in COVID-19 conspiracy theories as an important predictor of distress, anxiety, and job and life satisfaction among health care workers. This finding will enable mental health services to better target and provide help to mentally vulnerable health care workers during the ongoing COVID-19 pandemic.
This research assesses the influence of education development support, conceptual development support, and country support through entrepreneurial self-efficacy over green entrepreneurial intentions. ...A total of 532 business students in Ecuador participated in an online survey. Eight questions were focused on demographic information, and twenty-seven questions evaluated the green entrepreneurship intentions of students. An SEM-PLS technical analysis was used. The results showed that educational support for developing entrepreneurship (0.296), conceptual support for developing entrepreneurship (0.123), and country support for entrepreneurship (0.188) had a positive influence on entrepreneurial self-efficacy, and that entrepreneurial self-efficacy had a positive influence (0.855) on gren entrepreneurial intentions. The model explained 73.1% of the green entrepreneurial intentions. Outcomes of the bootstrapping test were used to evaluate if the path coefficients are significant. This study showed the impacts of education development support, conceptual development support, and country support on the entrepreneur’s ability to carry out green entrepreneurship were positive. This information can help universities develop strategic plans to achieve ecological ventures and ensure students have the necessary skills to do so on campus. The research findings also may be helpful for the governments in establishing new norms to promote entrepreneurship. The novelty is based on using the partial least square structural equation modeling (PLS-SEM) technique.
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