2,748 research outputs found

    Scalable production of graphene inks via wet-jet milling exfoliation for screen-printed micro-supercapacitors

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    The miniaturization of energy storage units is pivotal for the development of next-generation portable electronic devices. Micro-supercapacitors (MSCs) hold a great potential to work as on-chip micro-power sources and energy storage units complementing batteries and energy harvester systems. The scalable production of supercapacitor materials with cost-effective and high-throughput processing methods is crucial for the widespread application of MSCs. Here, we report wet-jet milling exfoliation of graphite to scale-up the production of graphene as supercapacitor material. The formulation of aqueous/alcohol-based graphene inks allows metal-free, flexible MSCs to be screen-printed. These MSCs exhibit areal capacitance (Careal) values up to 1.324 mF cm-2 (5.296 mF cm-2 for a single electrode), corresponding to an outstanding volumetric capacitance (Cvol) of 0.490 F cm-3 (1.961 F cm-3 for a single electrode). The screen-printed MSCs can operate up to power density above 20 mW cm-2 at energy density of 0.064 uWh cm-2. The devices exhibit excellent cycling stability over charge-discharge cycling (10000 cycles), bending cycling (100 cycles at bending radius of 1 cm) and folding (up to angles of 180{\deg}). Moreover, ethylene vinyl acetate-encapsulated MSCs retain their electrochemical properties after a home-laundry cycle, providing waterproof and washable properties for prospective application in wearable electronics

    Protective ostomies in ovarian cancer surgery: a systematic review and meta-analysis

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    Objective: To assess the benefit of protective ostomies on anastomotic leak rate, urgent re-operations, and mortality due to anastomotic leak complications in ovarian cancer surgery. Methods: A systematic literature search was performed in MEDLINE, Web of Science, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials for all studies on anastomotic leak and ostomy formation related to ovarian cancer surgery. Non-controlled studies, case series, abstracts, case reports, study protocols, and letters to the editor were excluded. Meta-analysis was performed on the primary endpoint of anastomotic leak rate. Subgroup analysis was carried out based on type of bowel resection and bevacizumab use. Secondary endpoints were urgent re-operations and mortality associated with anastomotic leak, length of hospital stay, postoperative complications, 30-day readmission rate, adjuvant chemotherapy, survival, and reversal surgery in ostomy and non-ostomy patients. Results: A total of 17 studies (2,719 patients) were included: 16 retrospective cohort studies, and 1 case-control study. Meta-analysis of 17 studies did not show a decrease in anastomotic leak rate in ostomy patients (odds ratio [OR]=1.01; 95% confidence interval [CI]=0.60–1.70; p=0.980). Meta-analysis of ten studies (1,452 women) did not find a decrease in urgent re-operations in the ostomy group (OR=0.72; 95% CI=0.35–1.46; p=0.360). Other outcomes were not considered for meta-analysis due to the lack of data in included studies. Conclusion: Protective ostomies did not decrease anastomotic leak rates, and urgent re-operations in ovarian cancer surgery. This evidence supports the use of ostomies in very select cases

    Explainable artificial intelligence toward usable and trustworthy computer-aided diagnosis of multiple sclerosis from Optical Coherence Tomography

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    Background: Several studies indicate that the anterior visual pathway provides information about the dynamics of axonal degeneration in Multiple Sclerosis (MS). Current research in the field is focused on the quest for the most discriminative features among patients and controls and the development of machine learning models that yield computer-aided solutions widely usable in clinical practice. However, most studies are conducted with small samples and the models are used as black boxes. Clinicians should not trust machine learning decisions unless they come with comprehensive and easily understandable explanations. Materials and methods: A total of 216 eyes from 111 healthy controls and 100 eyes from 59 patients with relapsing-remitting MS were enrolled. The feature set was obtained from the thickness of the ganglion cell layer (GCL) and the retinal nerve fiber layer (RNFL). Measurements were acquired by the novel Posterior Pole protocol from Spectralis Optical Coherence Tomography (OCT) device. We compared two black-box methods (gradient boosting and random forests) with a glass-box method (explainable boosting machine). Explainability was studied using SHAP for the black-box methods and the scores of the glass-box method. Results: The best-performing models were obtained for the GCL layer. Explainability pointed out to the temporal location of the GCL layer that is usually broken or thinning in MS and the relationship between low thickness values and high probability of MS, which is coherent with clinical knowledge.Conclusions: The insights on how to use explainability shown in this work represent a first important step toward a trustworthy computer-aided solution for the diagnosis of MS with OCT

    Explainable artificial intelligence toward usable and trustworthy computer-aided early diagnosis of multiple sclerosis from Optical Coherence Tomography

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    Background: Several studies indicate that the anterior visual pathway provides information about the dynamics of axonal degeneration in Multiple Sclerosis (MS). Current research in the field is focused on the quest for the most discriminative features among patients and controls and the development of machine learning models that yield computer-aided solutions widely usable in clinical practice. However, most studies are conducted with small samples and the models are used as black boxes. Clinicians should not trust machine learning decisions unless they come with comprehensive and easily understandable explanations. Materials and methods: A total of 216 eyes from 111 healthy controls and 100 eyes from 59 patients with relapsing-remitting MS were enrolled. The feature set was obtained from the thickness of the ganglion cell layer (GCL) and the retinal nerve fiber layer (RNFL). Measurements were acquired by the novel Posterior Pole protocol from Spectralis Optical Coherence Tomography (OCT) device. We compared two black-box methods (gradient boosting and random forests) with a glass-box method (explainable boosting machine). Explainability was studied using SHAP for the black-box methods and the scores of the glass-box method. Results: The best-performing models were obtained for the GCL layer. Explainability pointed out to the temporal location of the GCL layer that is usually broken or thinning in MS and the relationship between low thickness values and high probability of MS, which is coherent with clinical knowledge. Conclusions: The insights on how to use explainability shown in this work represent a first important step toward a trustworthy computer-aided solution for the diagnosis of MS with OCT

    CB1 cannabinoid receptor enrichment in the ependymal region of the adult human spinal cord

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    Cannabinoids are involved in the regulation of neural stem cell biology and their receptors are expressed in the neurogenic niches of adult rodents. In the spinal cord of rats and mice, neural stem cells can be found in the ependymal region, surrounding the central canal, but there is evidence that this region is largely different in adult humans: lacks a patent canal and presents perivascular pseudorosettes, typically found in low grade ependymomas. Using Laser Capture Microdissection, Taqman gene expression assays and immunohistochemistry, we have studied the expression of endocannabinoid system components (receptors and enzymes) at the human spinal cord ependymal region. We observe that ependymal region is enriched in CB1 cannabinoid receptor, due to high CB1 expression in GFAP+ astrocytic domains. However, in human spinal cord levels that retain central canal patency we found ependymal cells with high CB1 expression, equivalent to the CB1HIGH cell subpopulation described in rodents. Our results support the existence of ependymal CB1HIGH cells across species, and may encourage further studies on this subpopulation, although only in cases when central canal is patent. In the adult human ependyma, which usually shows central canal absence, CB1 may play a different role by modulating astrocyte functions

    Oligocene to present shallow subduction beneath the southern Puna plateau

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    The southern Puna plateau is a conspicuous example of a high-elevation orogenic plateau in a non-collisional setting. This orogenic sector is currently located above an anomalously shallow subduction segment, in which timing and relation to upper-plate tectonics have been widely overlooked. This subduction segment, here referred to as the southern Puna shallow subduction (SPSS), is characterized by a ~200 km wide shallow area located at ~300 km from the trench at a depth of ~100–120 km and dipping 10–12° to the east. To determine the onset of the SPSS and its link to the tectonic and magmatic activity in this region, we analyzed the tectonomagmatic record of the southern Puna plateau from preexisting datasets. Also, we present a new approach based on global subduction data that provides a straightforward methodology to extract potential paleo-slab angles from the bedrock arc record. This analysis reveals that a pronounced eastward arc-front migration and magmatic broadening took place at ~26 Ma and was preceded by ~4 Ma of reduced magmatic activity, which we link to the inception of the SPSS. As expected in shallow subduction settings, a change to basement-cored distributed deformation south of 25°S in the southern Puna plateau coincides with the beginning of shallow subduction. Also, the SPSS is coincident with the enigmatic post-Eocene intraplate deformation of the Otumpa Hills located at ~950 km from the trench. We suggest that this succession of events is not fortuitous and that the development of the SPSS impacted directly the overriding plate since the Oligocene contributing to the building of one of the largest topographies (>3 km) and thickest orogenic crusts (~70–60 km) on Earth. The shallow subduction would have acted jointly with Cenozoic changes in plate kinematics and climate enhancing Andean orogenesis at studied latitudes.Fil: Gianni, Guido Martin. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Garcia, Hector Pedro Antonio. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, FĂ­sicas y Naturales. Instituto GeofĂ­sico SismolĂłgico Volponi; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Juan; ArgentinaFil: Pesce, Agustina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, FĂ­sicas y Naturales. Instituto GeofĂ­sico SismolĂłgico Volponi; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Juan; ArgentinaFil: Lupari, Marianela Nadia. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, FĂ­sicas y Naturales. Instituto GeofĂ­sico SismolĂłgico Volponi; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Juan; ArgentinaFil: GonzĂĄlez, Marcelo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, FĂ­sicas y Naturales. Instituto GeofĂ­sico SismolĂłgico Volponi; ArgentinaFil: Giambiagi, Laura Beatriz. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales; Argentin

    Assessment of visual function and the neuroretina in subjects diagnosed with congenital anomaly of color vision

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    This cross-sectional and observational study includes 50 eyes of subjects with color blindness and 50 eyes of control subjects. Visual function (visual acuity, contrast sensitivity, and color vision) and neuroretinal structure were assessed in all subjects using optical coherence tomography (OCT). Significant thinning of the retinal nerve fiber layer, ganglion cell layer, and retina were observed in the color blindness group. Significant thinning was also recorded in layers that involve photoreceptor nuclei (between the outer limiting layer and the Bruch membrane and between the outer plexiform layer and the outer limiting membrane). OCT evaluation based on retinal segmentation is a rapid (5–10 minutes) non-invasive technique and seems to be a good biomarker of color blindness

    Polystyrene nanoplastics target lysosomes interfering with lipid metabolism through the PPAR system and affecting macrophage functionalization

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    Altres ajuts: acords transformatius de la UABNanoplastics (NPs) are currently a main concern for environmental, animal and human health due to their potential to accumulate in different environmental compartments and provoke effects in living organisms. Nevertheless, neither these effects nor the interaction of NPs with the cellular machinery are well characterized, and only scattered information is available. In the present work, we focused on the interaction between NPs and fish cells, both intestinal cells and macrophages, in order to understand which cell organelles are targeted by polystyrene (PS)-NPs and how this could impact cell function. PS-NPs can pass through phospholipid membranes, entering cells via endocytosis, phagocytosis or passive transport. Once internalized, we found that PS-NPs co-localize with lysosomes but not with mitochondria. Moreover, using two types of fluorescent probe (HDCFDA and DHE) we demonstrated that NPs did not trigger the production of reactive oxygen species (ROS), which was corroborated by the fact that neither the oxidative consumption ratio (OCR) nor the extracellular acidification rate (ECAR) in mitochondrial respiration were altered. RNASeq data revealed clear interference by PS-NPs with lipid metabolism, peroxisomes and PPAR signaling. The M1/M2 balance critically determines tissue homeostasis when exposed to exogenous agents such as microorganisms or pollutants. Thus, the expression of different genes (il1ÎČ, tnfα, il6, il10, il12, cox2, mmp9, ppar a, b and g) was further assessed to characterize the macrophage phenotype M1 or M2, induced by PS-NPs. Overall, in this study we demonstrate that PS-NPs co-localize within lysosomes, both in macrophages and in intestinal cells of rainbow trout, but do not trigger ROS production nor alter mitochondrial respiration. In macrophages, PS-NPs modulate polarization towards the M2-like phenotype

    α-Hispanolol Induces Apoptosis and Suppresses Migration and Invasion of Glioblastoma Cells Likely via Downregulation of MMP-2/9 Expression and p38MAPK Attenuation

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    α-Hispanolol (α-H) is a labdane diterpenoid that has been shown to induce apoptosis in several human cancer cells. However, the effect of α-H in human glioblastoma cells has not been described. In the present work, we have investigated the effects of α-H on apoptosis, migration, and invasion of human glioblastoma cells with the aim of identifying the molecular targets underlying its mechanism of action. The results revealed that α-H showed significant cytotoxicity against human glioma cancer cell lines U87 and U373 in a concentration- and time-dependent manner. This effect was higher in U87 cells and linked to apoptosis, as revealed the increased percentage of sub-G1 population by cell cycle analysis and acquisition of typical features of apoptotic cell morphology. Apoptosis was also confirmed by significant presence of annexin V-positive cells and caspase activation. Pretreatment with caspase inhibitors diminishes the activities of caspase 8, 9, and 3 and maintains the percentage of viable glioblastoma cells, indicating that α-H induced cell apoptosis through both the extrinsic and the intrinsic pathways. Moreover, we also found that α-H downregulated the anti-apoptotic Bcl-2 and Bcl-xL proteins and activated the pro-apoptotic Bid and Bax proteins. On the other hand, α-H exhibited inhibitory effects on the migration and invasion of U87 cells in a concentration-dependent manner. Furthermore, additional experiments showed that α-H treatment reduced the enzymatic activities and protein levels of matrix metalloproteinase MMP-2 and MMP-9 and increased the expression of TIMP-1 inhibitor, probably via p38MAPK regulation. Finally, xenograft assays confirmed the anti-glioma efficacy of α-H. Taken together, these findings suggest that α-H may exert anti-tumoral effects in vitro and in vivo through the inhibition of cell proliferation and invasion as well as by the induction of apoptosis in human glioblastoma cells. This research describes α-H as a new drug that may improve the therapeutic efficacy against glioblastoma tumors.This study was supported by grant PI11/00036, PI14/00055, and PI17/00012 from the FIS, MPY 1410/09 from ISCIII and Spanish Ministry of Health (Instituto de Salud Carlos III; RD12/0036/0059) to SoH and by grants IERPY 1149/16 and IERPY-M 389/18 to AL. L JG was supported by FIS (FI12/00340). SaH was supported by IERPY 1149/16 from ISCIII.S
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