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Context: In this work, a new polymeric structure was designed consisting of a nanometric sheet of graphene (G) and a polymethylmethacrylate (PMMA) repeat unit, which was designated as PMMA-G. Three degrees of polymerization of PMMA-G were considered: monomer (PMMA-G1), dimer (PMMA-G2), and trimer (PMMA-G3). The effect of incorporating a nanometric sheet of graphene into the molecular structure of PMMA on the modification of some of its main optical, magnetic, and electrical properties was investigated. Currently, the study presented here is of great relevance since various areas of technology require new materials with specific properties for the development of new devices. The results of our study reveal that the dielectric constant of PMMA is reduced when graphene is incorporated. However, a percentage increase of 14.48% in the refractive index of PMMA when graphene is inserted to form the nanocomposite is observed. It is found that the absolute value of molar magnetic susceptibility of PMMA increases considerably when reinforced with graphene. Finally, when reinforcing PMMA with graphene to obtain the PMMA-G nanocomposite, the electrical resistivity increases by almost an order of magnitude. Methods: We used computational tools under Materials Studio (MS) software. We built a PMMA molecule with three degrees of polymerization, graphene sheet, and polymethylmethacrylate-graphene composite (PMMA-G) was built also with three degrees of polymerization using a concentration of 50% graphene over the PMMA polymer. For each structure, we used computational code DMol3 of MS, which is based on the Density Functional Theory, and the geometry optimization process was carried out to obtain the most stable structures. Finally, using the connectivity indices method together with topological properties of the molecular structures, implemented in Synthia computational code of MS software, we calculated the dielectric constant, magnetic susceptibility, refractive index, and electrical resistivity, for pure PMMA and PMMA-G structures for their three degrees of polymerization. The results were analyzed, and the changes in these properties were discussed in terms of the effect of an electric and magnetic field on the molecular structures of PMMA-G with respect to PMMA. [ABSTRACT FROM AUTHOR]

In this paper, we establish some relationships between the main intrinsic invariants, scalar and Ricci curvatures, and the main extrinsic invariant, the mean curvature vector, for slant submanifolds of S-space-forms. In addition to that, we study those slant submanifolds satisfying the equality case between the above invariants, due to the great importance that these submanifolds have had in both complex and contact geometry. Moreover, we present some examples on these conditions. [ABSTRACT FROM AUTHOR]

This paper presents a general method for producing randomly perturbed density operators subject to different sets of constraints. The perturbed density operators are a specified "distance" away from the state described by the original density operator. This approach is applied to a bipartite system of qubits and used to examine the sensitivity of various entanglement measures on the perturbation magnitude. The constraint sets used include constant energy, constant entropy, and both constant energy and entropy. The method is then applied to produce perturbed random quantum states that correspond with those obtained experimentally for Bell states on the IBM quantum device ibmq_manila. The results show that the methodology can be used to simulate the outcome of real quantum devices where noise, which is important both in theory and simulation, is present. [ABSTRACT FROM AUTHOR]

The Patagonia region encompasses pristine ecosystems developed under cold climates. The effect of global warming in the region has not been fully assessed. The objective of this study was to identify susceptible areas to an increase in temperature affecting soil organic carbon mineralization and therefore carbon dioxide emissions. Soil carbon stocks were inferred from land use data obtained from the regional inventory, and regional temperatures were analyzed using Terra moderate-resolution imaging spectroradiometer images in PCI-Geomatica and Idrisi-Selva softwares. Temperature data (monthly, 2000–2012) were classified as: below 1 °C, 1–4 °C, > 4–10 °C, >10–20 °C and > 20 °C. Areas of fragility to soil C mineralization were classified according to the potential response of soil biological activity to the temperature (at 4 °C threshold). The classes analyzed were classified as Fragile-1, being colder and more responsive than Fragile-2 and Fragile-3 categories. Areas of first concern fragility to carbon decomposition occupied around 145,750 ha, representing about 1% of the natural ecosystems of the region. Over 60% of these areas are covered by peatlands. Projections indicate that these fragile ecosystems will be subjected to temperature increases of 1.0 to 1.5 °C in the medium term and to 1.5 to 2.0 °C in the long term, respectively, in the scenario RCP-4.5 of climate change. Under a more severe scenario (RCP-8.5), temperatures will rise + 0.5 °C over the RCP-4.5. The information provided here will address future research and support policy making decisions for the region. [ABSTRACT FROM AUTHOR]

Objetive: To evaluate, over a 79.2-month follow-up period, the behavior of bone mineral density (BMD) determined by Computerized Axial Densitometry (DXA), volumetric bone mineral density (BMDvol) and its relationship with anthropometric data, together with the parameters related to bone metabolism (calcium, phosphorus, alkaline phosphatase, parathormone (PTH) and vitamin D (25-OH-D3)) in a child population with Type 1 Diabetes Mellitus (DM1) without microvascular complications and a control group of reference with similar characteristics. Material and methods: Initially, a cross-sectional study was carried out in 40 diabetic children (mean age 9.4±2.8 years) and 108 controls (9.3±1.5 years) to assess the possible differences between the two populations. 26 patients from the initial diabetic group were reassessed after 79.2 months of follow-up. Results: It was observed that, at baseline, bone mass was similar in diabetics and controls. After follow-up, the BMD of the diabetic children was much lower than that expected in the non-diabetic child population. Weight, height, and Body Mass Index (BMI) followed the same pattern as BMD. The values of calcium, phosphorus, alkaline phosphatase, PTH and vitamin D, although within the normal range, were lower than in the controls. Alkaline phosphatase did not increase in the pubertal period. Conclusions: The present study demonstrates that children and adolescents with a recent diagnosis of DM1 have a normal BMD. However, over time, and especially during adolescence, they show less bone mass gain and changes in bone turnover parameters. [ABSTRACT FROM AUTHOR]

Objetive: To evaluate, over a 79.2-month follow-up period, the behavior of bone mineral density (BMD) determined by Computerized Axial Densitometry (DXA), volumetric bone mineral density (BMDvol) and its relationship with anthropometric data, together with the parameters related to bone metabolism (calcium, phosphorus, alkaline phosphatase, parathormone (PTH) and vitamin D (25-OH-D3)) in a child population with Type 1 Diabetes Mellitus (DM1) without microvascular complications and a control group of reference with similar characteristics. Material and methods: Initially, a cross-sectional study was carried out in 40 diabetic children (mean age 9.4±2.8 years) and 108 controls (9.3±1.5 years) to assess the possible differences between the two populations. 26 patients from the initial diabetic group were reassessed after 79.2 months of follow-up. Results: It was observed that, at baseline, bone mass was similar in diabetics and controls. After follow-up, the BMD of the diabetic children was much lower than that expected in the non-diabetic child population. Weight, height, and Body Mass Index (BMI) followed the same pattern as BMD. The values of calcium, phosphorus, alkaline phosphatase, PTH and vitamin D, although within the normal range, were lower than in the controls. Alkaline phosphatase did not increase in the pubertal period. Conclusions: The present study demonstrates that children and adolescents with a recent diagnosis of DM1 have a normal BMD. However, over time, and especially during adolescence, they show less bone mass gain and changes in bone turnover parameters. [ABSTRACT FROM AUTHOR]

Background: Type I interferons are widely used in research applications and as biotherapeutics. Current assays used to measure interferon concentrations, such as plaque reduction assays and ELISA, are expensive, technically challenging, and may take days to provide results. We sought to develop a robust and rapid assay to determine interferon concentrations produced from transiently transfected cell cultures. Method: Indirect quantification of recombinant interferon was evaluated using a novel bi-cistronic construct encoding the Foot-and-mouth disease virus 2A translational interrupter sequence to yield equimolar expression of Gaussia princeps luciferase and porcine interferon α. Direct quantification was evaluated by expression of a novel fusion protein comprised of Gaussia princeps luciferase and porcine type I interferon. Plasmids encoding constructs are transiently transfected into cell cultures and supernatant harvested for testing of luminescence, ELISA determined concentration, and anti-viral activity against vesicular stomatitis virus. Results: Bi-cistronic constructs, utilized for indirect quantification, demonstrate both luciferase activity and anti-viral activity. Fusion proteins, utilized for direct quantification, retained secretion and luminescence however only the interferon α fusion protein had antiviral activity comparable to wildtype porcine interferon α. A strong linear correlation was observed between dilution and luminescence for all compounds over a dynamic range of concentrations. Conclusion: The correlation of antiviral and luciferase activities demonstrated the utility of this approach, both direct and indirect, to rapidly determine recombinant interferon concentrations. Concentration can be determined over a more dynamic concentration range than available ELISA based assays using this methodology. [ABSTRACT FROM AUTHOR]

Mesothelioma is a rare and aggressive tumour with dismal prognosis arising in the pleura and associated with asbestos exposure. Its incidence is on the rise worldwide. In selected patients with early-stage MPM, a maximal surgical cytoreduction in combination with additional antitumour treatment may be considered in selected patients assessed by a multidisciplinary tumor board. In patients with unresectable or advanced MPM, chemotherapy with platinum plus pemetrexed is the standard of care. Currently, no standard salvage therapy has been approved yet, but second-line chemotherapy with vinorelbine or gemcitabine is commonly used. Novel therapeutic approaches based on dual immunotherapy or chemotherapy plus immunotherapy demonstrated promising survival benefit and will probably be incorporated in the future. [ABSTRACT FROM AUTHOR]

Objective: We sought to identify factors that influence Human Papillomavirus (HPV) vaccination rates in individuals at two higher education institutions in South Carolina (SC). Participants: We surveyed 1007 students with a mean age and standard deviation of 20.3 ± 3.3 from September 2018 to December 2018. Methods: Participants answered 13 questions, assessing HPV vaccination rates, demographics, and rationales for vaccination vs. non-vaccination. Results: Of 1007 respondents, 700 received HPV vaccination, 165 were unvaccinated, 75 received partial vaccination and 138 were uncertain. Commonalities in HPV vaccination existed between females (p = 0.037), individuals who received standard childhood vaccinations (p = 0.04), and those not native-born in SC (p < 0.001). Of non-vaccinated individuals, 37% "never thought about vaccination," 32% did not perceive a need for vaccination, and 31% reported vaccine safety as reasons for not receiving the vaccine. Conclusions: Promotion of HPV vaccination may benefit from targeting SC natives, males, and individuals who are under-vaccinated or unvaccinated. [ABSTRACT FROM AUTHOR]

We consider Type IIB compactifications on an isotropic torus T 6 threaded by geometric and non geometric fluxes. For this particular setup we apply supervised machine learning techniques, namely an artificial neural network coupled to a genetic algorithm, in order to obtain more than sixty thousand flux configurations yielding to a scalar potential with at least one critical point. We observe that both stable AdS vacua with large moduli masses and small vacuum energy as well as unstable dS vacua with small tachyonic mass and large energy are absent, in accordance to the refined de Sitter conjecture. Moreover, by considering a hierarchy among fluxes, we observe that perturbative solutions with small values for the vacuum energy and moduli masses are favored, as well as scenarios in which the lightest modulus mass is much smaller than the corresponding AdS vacuum scale. Finally we apply some results on random matrix theory to conclude that the most probable mass spectrum derived from this string setup is that satisfying the Refined de Sitter and AdS scale conjectures. [ABSTRACT FROM AUTHOR]

Background: Characterization of nevi involution could help to understand the biological behaviour of melanocytic neoplasms. Objective: To describe the frequency and morphology of naevus involution in a series of patients with atypical naevus syndrome under digital follow‐up with a SIAscopy program and, in a small sample of fading nevi, to analyse histopathological features and immunohistochemical biomarkers. Methods: Seventy‐four patients registered from April 2007 to July 2014 in the SIAscopy system of the Department of Dermatology of Hospital Arnau de Vilanova of Lleida, Spain, were reviewed. Fourteen naevus cases with fading features were prospectively excised during follow‐up. Eleven already excised naevus controls were randomly selected from our archive. Results: We observed that 81% of patients showed, at least, one involutive naevus and 25% of recorded nevi presented this phenomenon; the mean time of involution was 46.7 months. The predominant structural pattern was reticular (>70%), and the most frequently observed regression structures were vascular (33.8%). Histopathological significant higher intensity of inflammatory infiltrate in controls and higher presence of laminar and compact fibrosis and increase of vessels in cases were demonstrated. Regarding immunohistochemical biomarkers, only higher expression of cytoplasmic activated caspase 3 in controls was significant. Conclusions: Naevus involution is a common phenomenon in patients with dysplastic naevus syndrome. It is usually a slow process, more frequent in naevus with reticular pattern. SIAscopy regression structures are uncommon, with the exception of vascular ones. Histologically, fading involutive pattern is characterized by scarce inflammatory infiltrate and melanophages, delicate fibrosis and increase of vessels. [ABSTRACT FROM AUTHOR]

We present experimental results complemented with numerical simulations of a recently discovered instability observed in a free-surface flow driven by an azimuthal electromagnetic force in a thin annular layer of an electrolyte between two concentric cylindrical electrodes. The flow instability leads to the formation of travelling anticyclonic vortices near the external electrode. The vortices exist for long times once they appear. Experimental visualization of the flow using a tracer and thermographic images shows that the instability arises in both isothermal and nonisothermal conditions. Although multiple axisymmetric flow solutions can exist for the same set of governing parameters, a linear stability analysis indicates that only one of such solutions can potentially lead to azimuthally periodic vortex patterns observed in our experiments. Further, using a fully three-dimensional hybrid finite volume-spectral numerical method, the emergence of the instability is reproduced. [ABSTRACT FROM AUTHOR]

Purpose: The Spanish Society for Medical Oncology (SEOM, for its acronym in Spanish) and the National Commission for the Specialty of Medical Oncology seek to highlight the important workload and unrecognized dedication entailed in working as a Medical Oncology (MO) resident mentor, as well as its relevance for the quality of teaching units and the future of the specialty.Materials and methods: The current situation and opinion regarding the activity of MO resident mentors was analyzed by reviewing the standing national and autonomic community regulations and via an online survey targeting mentors, residents, and physicians who are not MO mentors. The project was supervised by a specially designated group that agreed on a proposal containing recommendations for improvement.Results: Of the MO mentors, 90% stated that they did not have enough time to perform their mentoring duties. An estimated 172 h/year on average was dedicated to mentoring, which represents 10.1% of the total time. MO mentors dedicate an average of 6.9 h/month to these duties outside their workday. Forty-five percent of the mentors feel that their role is scantly recognized, if at all.Conclusions: The study reveals the substantial dedication and growing complexity of MO resident mentoring. A series of recommendations are issued to improve the conditions in which it is carried out, including the design of systems that adapt to the professional activity in those departments that have time set aside for mentoring tasks. [ABSTRACT FROM AUTHOR]

Summary: The safety of a replication‐deficient, human adenovirus‐vectored foot‐and‐mouth disease virus (FMDV) serotype A24 Cruzeiro capsid‐based subunit vaccine (AdtA24) was evaluated in five independent safety studies. The target animal safety studies were designed in compliance with United States (U.S.) regulatory requirements (Title 9, U.S. Code of Federal Regulation [9CFR]) and international standard guidelines (VICH Topic GL‐44) for veterinary live vaccines. The first three studies were conducted in a total of 22 vaccinees and demonstrated that the AdtA24 master seed virus (MSV) was safe, did not revert to virulence and was not shed or spread from vaccinees to susceptible cattle or pigs. The fourth safety study conducted in 10 lactating cows using an AdtA24 vaccine serial showed that the vaccine was completely absent from milk. The fifth safety study was conducted under typical U.S. production field conditions in 500 healthy beef and dairy cattle using two AdtA24 vaccine serials. These results demonstrated that the vaccine was safe when used per the product label recommendations. Additional data collected during these five studies confirmed that AdtA24 vaccinees developed FMDV A24 and the HAd5 vaccine vector serum neutralization antibodies that test negative in a FMDV non‐structural protein antibody test, confirming AdtA24 vaccine's capability to differentiate infected from vaccinated animals (DIVA). In conclusion, results from this comprehensive set of cattle studies demonstrated the safety of the replication‐deficient AdtA24 vaccine and fulfilled safety‐related requirements for U.S. regulatory requirements. [ABSTRACT FROM AUTHOR]

Background: In addition to the mutational status of KRAS, the epidermal growth factor receptor (EGFR) ligands amphiregulin (AREG) and epiregulin (EREG) might function as bona fide biomarkers of cetuximab (Ctx) sensitivity for most EGFR-driven carcinomas.Methods: Lentivirus-delivered small hairpin RNAs were employed to specifically reduce AREG or EREG gene expression in wild-type KRAS A431 squamous cell carcinoma cells. Colony-forming assays were used to monitor the impact of AREG and EREG knockdown on Ctx efficacy. Amphiregulin and EREG protein expression levels were assessed by quantitative ELISA in parental A431 cells and in pooled populations of A431 cells adapted to grow in the presence of Ctx. A phosphoproteomic platform was used to measure the relative level of phosphorylation of 42 distinct receptor tyrosine kinases before and after the acquisition of resistance to Ctx.Results: Stable gene silencing of either ligand was found to notably reduce the expression of the other ligand. Parental A431 cells with normal expression levels of AREG/EREG exhibited significantly increased growth inhibition in response to Ctx, compared with derivatives that are engineered to produce minimal AREG/EREG. The parental A431 cells acutely treated with Ctx exhibited reduced basal expression levels of AREG/EREG. Pooled populations of Ctx-resistant A431 cells expressed significantly lower levels of AREG/EREG and were insensitive to the downregulatory effects of Ctx. Phosphoproteomic screen identified a remarkable hyperactivation of FGFR3 in Ctx-resistant A431 cells, which gained sensitivity to the cytotoxic and apoptotic effects of the FGFR3 TK inhibitor PD173074. The A431 parental cells acutely treated with Ctx rapidly activated FGFR3 and their concomitant exposure to Ctx and PD173074 resulted in synergistic apoptosis.Conclusion: Cross-suppression of AREG/EREG expression may explain the tight co-expression of AREG and EREG, as well as their tendency to be more highly expressed than other EGFR ligands to determine Ctx efficacy. The positive selection for Ctx-resistant tumour cells exhibiting AREG/EREG cross-suppression may have an important role in the emergence of Ctx resistance. As de-repression of FGFR3 activity rapidly replaces the loss of EGFR-ligand signalling in terms of cell proliferation and survival, combinations of Ctx and FGFR3-targeted drugs may be a valuable strategy to enhance the efficacy of single Ctx while preventing or delaying acquired resistance to Ctx. [ABSTRACT FROM AUTHOR]

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Introduction: Medication errors are frequent at care transition points and can have serious repercussions. Study objectives were to examine the frequency/type of reconciliation errors at hospital admission and discharge and to report on the drugs involved, associated risk factors and potential to cause harm in a healthcare setting with comprehensive digital health records.Material and Methods: A prospective observational 2-year study was conducted in the Internal Medicine Department of a regional hospital. The best possible medication history was obtained from different sources by clinical pharmacists and compared with prescriptions at admission and discharge. The frequency and type of reconciliation errors were studied at admission and discharge, evaluating risk factors for their occurrence and their potential to cause harm.Results: The study included 814 patients (mean age: 80.2 years). At least one reconciliation error was detected in 525 (64.5%) patients at admission, with a mean of 2.2 ± 1.3 errors per patient and in 235 (32.4%) patients at discharge. Drug omission was the most frequent reconciliation error (73.6% at admission and 71.4% at discharge); 39% of errors at admission and 51% at discharge had potential to cause moderate or severe harm. The risk of error at admission was higher with more pre-admission drugs (p < 0.001) and, among patients with reconciliation errors, the number of errors was significantly higher in those receiving more drugs pre-admission or with more comorbidities. The risk at discharge was higher in patients with more drugs prescribed at discharge (p = 0.04) and in those with a longer hospital stay (p = 0.03).Conclusions: Medication reconciliation procedures are required to minimise medication discrepancies and enhance patient safety. Integration of patient health records across care levels is necessary but not sufficient to prevent errors. [ABSTRACT FROM AUTHOR]

We describe of an instability in a free surface flow produced by an azimuthal Lorentz force in a layer of an electrolyte contained in an open electromagnetic stirrer with cylindrical geometry. The force is created by the interaction of an applied radial electric current within the range 25-400 mA and an approximately constant magnetic field (0.04 T) parallel to the cylinder's axis. The flow instability leads to the formation of cyclonic vortices close to the internal electrode and anticyclonic vortices close to the external electrode, in the plane normal to the magnetic field. Flow visualization using dye reveals that the travelling anticyclonic vortices remain for long times once they appear. Detailed flow patterns are explored through Particle Image Velocimetry measurements with the aim of clarifying the mechanisms that originate the vortex formation. [ABSTRACT FROM AUTHOR]