Abstract Background A variety of NADPH oxidase (Nox) isoforms including Noxs 1, 2, 4 and 5 catalyze the formation of reactive oxygen species (ROS) in the vascular wall. The Nox2 isoform complex has ...arguably received the greatest attention in the progression of atherogenesis in animal models. Thus, in the current study we postulated that specific Nox2 oxidase inhibition could reverse or attenuate atherosclerosis in mice fed a high-fat diet. Methods We evaluated the effect of isoform-selective Nox2 assembly inhibitor on the progression and vascularization of atheromatous plaques. Apolipoprotein E-deficient mice (ApoE−/−) were fed a high fat diet for two months and treated over 15 days with Nox2ds-tat or control sequence (scrambled); 10 mg/kg/day, i.p . Mice were sacrificed and superoxide production in arterial tissue was detected by cytochrome C reduction assay and dihydroethidium staining. Plaque development was evaluated and the angiogenic markers VEGF, HIF1-α and visfatin were quantified by real time qRT-PCR. MMP-9 protein release and gelatinolytic activity was determined as a marker for vascularization. Results Nox2ds-tat inhibited Nox-derived superoxide determined by cytochrome C in carotid arteries (2.3 ± 0.1 vs 1.7 ± 0.1 O2•− nmol/min*mg protein; P < 0.01) and caused a significant regression in atherosclerotic plaques in aorta (66 ± 6 μm2 vs 37 ± 1 μm2 ; scrmb vs. Nox2ds-tat; P < 0.001). Increased VEGF, HIF-1α, MMP-9 and visfatin expression in arterial tissue in response to high-fat diet were significantly attenuated by Nox2ds-tat which in turn impaired both MMP-9 protein expression and activity. Conclusion Given these results, it is quite evident that selective Nox inhibitors can reverse vascular pathology arising with atherosclerosis.
It has been found that both preparedness for disasters and public response are significantly influenced by risk perceptions and trust in authorities and experts. Although Chile is a country with a ...long history of natural disasters, few studies have evaluated the risk perceptions of natural hazards or the degree of social trust. The aim of this study was to evaluate risk perception in Chile regarding various natural hazards and the degree of trust on authorities and institutions. A survey was conducted in five major cities in Chile during the year 2013 and was completed by a total sum of 2054 participants. We assessed risk perception of nine natural hazards and the level of trust in ten national institutions and authorities. According to declared levels of trust, the institutions and authorities included in this study were categorized into three groups: (1) low trust, which included governmental authorities and institutions; (2) medium trust, formed by institutions with educational and preparation roles; and (3) high trust, formed by institutions and authorities responsible for maintaining public order and conducting rescue and aid operations. Although our results show that earthquakes, tsunamis and wildfires were natural hazards of greatest concern to the national population, they also reflect that there are specific additional concerns in different cities that are coherent with their individual history of natural disasters. Implications for natural disaster risk preparedness are discussed.
•Low-cycle fatigue tests of SFRC of the same matrix but various fiber ratios.•There is an optimum fiber ratio that gets the longest fatigue life.•Ratios bigger than the optimum distort the matrix and ...shorten fatigue life.•The secondary strain rate per cycle vs. fatigue life relationship depends only on the matrix.•A strain-based fatigue failure criterion is proposed.
An experimental campaign is presented to evaluate the influence of fiber content on compressive fatigue of self-compacting concrete reinforced with steel fibers. Five different fiber contents, from plain concrete up to a content of 0.8% in volume, are studied. Beneficial effect of fibers is observed in fatigue resistance. However, the longest fatigue life is not achieved with the highest fiber content, but rather with an intermediate one (0.6%). It has also been verified that the relationship of the secondary strain rate per cycle with the fatigue life is independent of the amount of fibers and therefore it depends only on the matrix. Based on these results, a strain-based fatigue failure criterion involving mechanical and time dependent deformation is proposed.
FeCl
3
·6H
2
O was anchored in the pores of a layered crystalline imine-based mesoporous covalent organic framework (TPB-DMTP-COF) with surface area of 1200 m
2
/g and pores of 34 Å, affording the ...material FeCl
3
@TPB-DMTP-COF that worked as iron based heterogeneous catalyst. This new porous material was used in the decarboxylative oxidation cross-coupling reaction of cinnamic acids showing good to excellent catalytic activity with good chemical yields and short reaction time. FeCl
3
@TPB-DMTP-COF exhibit moderate surface area (235 m
2
/g) and high thermal and chemical stability allowing it use for several catalytic cycles.
Graphical Abstract
Abstract
Gamma-ray bursts (GRBs) have been classified traditionally based on their duration. The increasing number of extended emission (EE) GRBs, lasting typically more than 2s but with properties ...similar to those of short GRBs, challenges the traditional classification criteria. In this work, we use the t-distributed stochastic neighbor embedding (t-SNE), a machine-learning technique, to classify GRBs. We present the results for GRBs observed until 2022 July by the Swift/BAT (Burst Alert Telescope) instrument in all its energy bands. We show the effects of varying the learning rate and perplexity parameters as well as the benefit of preprocessing the data by a nonparametric noise-reduction technique. Consistently with previous works, we show that the t-SNE method separates GRBs into two subgroups. We also show that EE GRBs reported by various authors under different criteria tend to cluster in a few regions of our t-SNE maps and identify seven new EE GRB candidates by using the gamma-ray data provided by the automatic pipeline of Swift/BAT and the proximity with previously identified EE GRBs.
A protocol to successfully transmit the huanglongbing (HLB) pathogen, '
Liberibacter asiaticus', between citrus plants by using the Asian citrus psyllid (ACP) and an alternative way to help growers ...control ACP are proposed. Best results were obtained when pathogen acquisition by adults reared on fully symptomatic '
Liberibacter asiaticus'-positive plants, latency, and inoculation occurred at ambient air temperatures ranging from 24 to 28°C and when a single infective adult ACP was confined for 7 days on soft, newly developing vegetative shoots (stages v2 to v4). No infection resulted from confinement of infective ACP adults on mature leaves (stage v6). Under the described conditions, single ACP adults could successfully transmit '
Liberibacter asiaticus' to an average of 56.5% (35 to 83%) of plantlets with v2 to v4 shoots growing in 0.3-liter tubes and to 80.5% (76 to 86%) of plants with v2 to v4 shoots growing in 4.7-liter pots. The use of single insects and plantlets reduces labor, space, and other resources necessary to undertake transmission tests. It also reduces time needed for transmission studies and should help accelerate research on HLB. The results were used to develop an index for favorability to infection (IFI) to determine orchard vulnerabilities to '
Liberibacter asiaticus'. The IFI is based on the heterogeneous population of new shoots that occurs on tree canopies and may offer alternative or complementary alternatives to the laborious and costly insect surveys currently used in most instances to determine threshold levels for insecticide applications.
This article presents the design process of innovative prototypes for cervical cancer prevention in primary care centers located in low-income settings in Cali, Colombia, using the Human-Centered ...Design (HCD). The project was developed in collaboration with a public healthcare network comprised of 38 urban and rural centers with women between the ages of 25 and 65 years, healthcare providers of the cancer program, healthcare administrators and the general manager of said network. Our HCD process involved five stages: research, need synthesis, ideation and co-design process, prototyping and in-context usability testing. In practice, some of the stages are overlapped and iterated throughout the design process. We conducted observations, open-ended interviews and conversations, multi-stakeholder workshops, focus groups, systematic text condensation analyses and tests in real contexts. As a result, we designed four prototypes: (1) 'Encanto': An educational manicure service, (2) 'No le des la espalda a la citología': A media-based strategy, (3) An educational wireless queuing device in the waiting room, and (4) Citobot: A cervical cancer early detection device, system, and method. The tests carried out with each prototype showed their value, limitations and possibilities in terms of subsequent development and validation through public health research or clinical research. We recognize that a longer-term evaluation is required in order to determine whether the prototypes will be used regularly, integrated into cervical cancer screening services and effectively improve access to cytology as a screening test. We conclude that HCD is a useful for design-based prevention in the field of cervical cancer. The integration of this approach with public health research would allow the generation of evidence during to the formulation of policies and programs as well as optimize existing interventions and, ultimately, facilitate the scalability and financing of what actually works.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Text mining enables search, extraction, categorisation and information visualisation. This study aimed to identify oral manifestations in patients with COVID-19 using text mining to ...facilitate extracting relevant clinical information from a large set of publications. A list of publications from the open-access COVID-19 Open Research Dataset was downloaded using keywords related to oral health and dentistry. A total of 694,366 documents were retrieved. Filtering the articles using text mining yielded 1,554 oral health/dentistry papers. The list of articles was classified into five topics after applying a Latent Dirichlet Allocation (LDA) model. This classification was compared to the author's classification which yielded 17 categories. After a full-text review of articles in the category “Oral manifestations in patients with COVID-19”, eight papers were selected to extract data. The most frequent oral manifestations were xerostomia (n = 405, 17.8%) and mouth pain or swelling (n = 289, 12.7%). These oral manifestations in patients with COVID-19 must be considered with other symptoms to diminish the risk of dentist-patient infection.
We report a detailed theoretical investigation of the structural and electronic properties of titanium- and nickel-doped defective graphene nanoplatelets, which are shown to be efficient materials ...for hydrogen storage. We found that H2 bond cleavage is favored by Ti4-doped defective graphene nanoplatelets because of the strong interaction between the hydrogen 1s and titanium 3d levels that leads to the formation of metal hydrides, while H2 adsorption on Ni4-doped defective graphene favors the formation of Kubas complexes as hydrogen 1s levels only interact with the nickel 4s levels. A comparison between adsorption energies, number of H2 adsorbed molecules, and hydrogen gravimetric content shows that Ti4-doped graphene has a better performance for hydrogen storage with a notably high hydrogen gravimetric content of 3.4 wt %; than Ni4-doped graphene with a 10-fold lower gravimetric content of only 0.30 wt %. This observation can be explained by three factors: Ti is a lighter transition metal, it absorbs a larger amount H2 per metallic atom, and it presents a planar geometry that increases the coverage of the graphene layer and makes possible that all atoms in the cluster participate in the H2 adsorption. Our results support the hypothesis that a controlled introduction of defects in graphene followed by the anchoring of small metallic clusters is a feasible way to enhance the hydrogen gravimetric content of graphene nanoplatelets and to fine-tune hydrogen absorption energies to achieve a reversible operation at ambient temperature and moderates pressures, addressing one of the main challenges of a sustainable hydrogen-based economy.
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