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Standing at the forefront of energetics research is the exploration of energetic binders. To avoid the traditionally used sensitive explosophores, we present the first reported energetic silicone polymers synthesized from a penta-oxadiazole monomer. These polymers exhibit properties that lie between, or exceed, the thermal properties of inert and commonly used energetic binders.
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In the present study, biopolymeric coatings of polyhydroxybutyrate (PHB) were deposited on 316L stainless steel substrates. The PHB coatings were developed using the spin coating method. To improve the adhesion of the PHB coating on the substrate, this method uses an atmospheric plasma treatment. Adhesion tests show a 156% increase in adhesion after 5 s of surface treatment. Raman spectroscopy analysis of the polymer shows the incorporation of functional groups and the formation of new hydrogen bonds, which can help us bind drugs and promote osteogenesis after plasma treatment. Additionally, the electrochemical behaviors in artificial body fluids (Hanks' solution) of the PHB coatings on the steel were evaluated with potentiodynamic tests, which revealed a decrease in the corrosion current and resistance to the transfer of the charge from the electrolyte to the 316L steel because of the PHB coating. All the PHB coatings were characterized using scanning electron microscopy and Raman spectroscopy after the electrochemical tests. This analysis confirmed the diffusion of electrolyte species toward the surface and the degradation of the polymer chain for the first 15 s of treatment with atmospheric plasma. These findings support the claim that plasma surface modification is a quick, environmentally friendly, and cost-effective method to enhance the performance of PHB coatings on 316L stainless steel for medical devices.
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The stability and reactivity of Pd4Ni4 and Pd4Cu4 clusters embedded on graphene modified by monovacancy and nitrogen doping were investigated using auxiliary density functional theory (ADFT) calculations. The most stable structure of the Pd4Ni4 cluster is found in high spin multiplicity, whereas the lowest stable energy structure of the Pd4Cu4 cluster is a close shell system. The interaction energies between the bimetallic clusters and the defective graphene systems are significantly higher than those reported in the literature for the Pd-based clusters deposited on pristine graphene. It is observed that the composites studied present a HOMO-LUMO gap less than 1 eV, which suggests that they may present a good chemical reactivity. Therefore, from the results obtained in this work it can be inferred that the single vacancy graphene and pyridinic N-doped graphene are potentially good support materials for Pd-based clusters.
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Objective: To analyze the safety profile of a nifedipine oral solution in the treatment of preterm labor (PTL). Methods: A multi-center, open-label, prospective, single-arm, observational study was conducted in 500 women with PTL to whom a nifedipine oral solution was prescribed according to its Summary of Product Characteristics. Safety profile and tolerability of oral administration of nifedipine solution during routine clinical practice was assessed as the primary objective of the study and treatment efficacy as secondary objective. Results: No severe adverse events were reported among these women, including severe hypotension. Eight patients (2.3%) reported adverse reactions of moderate intensity, and in 0.9% of the patients (3 cases), these adverse reactions caused the discontinuation of the treatment. Conclusions: The results of this study show that nifedipine oral solution exhibits an excellent safety profile used as a tocolytic treatment in women with PTL.(AU)
Objetivo: Analizar el perfil de seguridad de una solución oral de nifedipino en el tratamiento del parto prematuro (PP). Métodos: Se llevó a cabo un estudio observacional, prospectivo, de diseño abierto, de rama única y multicéntrico en 500 mujeres que presentaban un PP, a las que se les administró una solución oral de nifedipino según la ficha técnica del producto. El perfil de seguridad y la tolerancia de la solución oral de nifedipino, en el contexto de la práctica clínica rutinaria, fueron evaluados como objetivo primario del estudio, y la eficacia del tratamiento, como objetivo secundario. Resultados: No se notificaron efectos adversos graves, incluyendo hipotensión severa. Ocho pacientes (2,3%) presentaron reacciones adversas de intensidad moderada, y en el 0,9% de las pacientes (3 casos) estos efectos adversos provocaron la discontinuación del tratamiento. Conclusiones: Los resultados de este estudio muestran que la solución oral de nifedipino dispone de un excelente perfil de seguridad para su uso como tocolítico en el tratamiento de mujeres con PP.(AU)
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Humanos , Femenino , Adulto Joven , Adulto , Trabajo de Parto Prematuro/tratamiento farmacológico , Nifedipino/administración & dosificación , Nifedipino/efectos adversos , Tocólisis , Seguridad , Eficacia , Estudios Prospectivos , Ginecología , Servicio de Ginecología y Obstetricia en Hospital , ObstetriciaRESUMEN
CONTEXT: The detection and monitoring of CO gas are essential to avoid human health problems. Therefore, the CO adsorption on Pd2 and PdCo dimers deposited on pyridinic Nx-doped graphene (PNxG; x = 1 - 3) was investigated employing the auxiliary density functional theory. In the most stable arrangements for the Pd2 dimer supported on PNxG, a Pd atom is in the PNxG vacancy, and the other Pd atom is placed on C atoms. For the PdCo dimer deposited on PNxG, the most stable interaction is like Pd2 dimer supported on PNxG, but with the Co atom centered over the vacancy site. Concerning the stability of the Pd2 and PdCo dimers supported on PNxG, the interaction energies (Eint) of the PdCo dimer deposited on PNxG are higher than those obtained with the Pd2 dimer. Also, the Eint of Pd2 and PdCo dimers deposited on PNxG are higher than those supported on pristine graphene. The CO adsorption energies on Pd2/PNxG and PdCo/PNxG composites are higher than those reported in the literature for pristine graphene, showing that the Pd2/PNxG and PdCo/PNxG composites have a good sensitivity toward the CO molecule. METHODS: All electronic structure calculations were performed using the auxiliary density functional theory implemented in the deMon2k program. For exchange and correlation functional, the revised PBE was used. The Pd atoms were treated with an 18-electron QECP|SD basis set, while the remaining atoms were subjected to a DZVP-GGA basis set. The GEN-A2* auxiliary-function-set was used for all computations.
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This work presents a one-step synthesis methodology for preparing a hydrochar (HC) doped with TiO2 (HC-TiO2) for its application on the degradation of crystal violet (CV) using UV and visible radiation. Byrsonima crassifolia stones were used as precursors along with TiO2 particles. The HC-TiO2 sample was synthesized at 210 °C for 9 h using autogenous pressure. The photocatalyst was characterized to evaluate the TiO2 dispersion, specific surface area, graphitization degree, and band-gap value. Finally, the degradation of CV was investigated by varying the operating conditions of the system, the reuse of the catalyst, and the degradation mechanism. The physicochemical characterization of the HC-TiO2 composite showed good dispersion of TiO2 in the carbonaceous particle. The presence of TiO2 on the hydrochar surface yields a bandgap value of 1.17 eV, enhancing photocatalyst activation with visible radiation. The degradation results evidenced a synergistic effect with both types of radiation due to the hybridized π electrons in the sp2-hybridized structures in the HC surface. The degradation percentages were on average 20% higher using UV radiation than visible radiation under the following conditions: [CV] = 20 mg/L, 1 g/L of photocatalyst load, and pH = 7.0. The reusability experiments demonstrated the feasibility of reusing the HC-TiO2 material up to 5 times with a similar photodegradation percentage. Finally, the results indicated that the HC-TiO2 composite could be considered an efficient material for the photocatalytic treatment of water contaminated with CV.
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Violeta de Genciana , Rayos Ultravioleta , Luz , Titanio/química , CatálisisRESUMEN
In autoimmune Type 1 diabetes (T1D), immune cells progressively infiltrate and destroy the islets of Langerhans - islands of endocrine tissue dispersed throughout the pancreas. However, it is unclear how this process, called 'insulitis', develops and progresses within this organ. Here, using highly multiplexed CO-Detection by indEXing (CODEX) tissue imaging and cadaveric pancreas samples from pre-T1D, T1D, and non-T1D donors, we examine pseudotemporal-spatial patterns of insulitis and exocrine inflammation within large pancreatic tissue sections. We identify four sub-states of insulitis characterized by CD8 + T cells at different stages of activation. We further find that exocrine compartments of pancreatic lobules affected by insulitis have distinct cellularity, suggesting that extra-islet factors may make particular lobules permissive to disease. Finally, we identify "staging areas" - immature tertiary lymphoid structures away from islets where CD8 + T cells appear to assemble before they navigate to islets. Together, these data implicate the extra-islet pancreas in autoimmune insulitis, greatly expanding the boundaries of T1D pathogenesis.
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El dolor abdominal es un síntoma inespecífico, común a múltiples procesos, con una alta prevalencia en la población general. Representa el 15-20% de los motivos de consulta en los servicios de urgencias.1 La mayoría de estos dolores tienen una etiología benigna, por lo que el objetivo inicial de la asistencia médica es identificar a aquellos pacientes cuyo dolor abdominal sea debido a una patología grave2. En ocasiones, puede tener una evolución tanto rápida como tórpida pudiendo provocar un abdomen agudo. El abdomen agudo se define como un dolor abdominal de instauración reciente, que requiere de un diagnóstico rápido y preciso debido a la posibilidad de que derive en un tratamiento quirúrgico urgente. Para ello es importante una buena anamnesis y exploración, enfocado a detectar signos y síntomas de alarma. Si no es diagnosticado y tratado de forma adecuada y precoz, puede originar consecuencia como sepsis, shock, insuficiencia renal, con elevada mortalidad3. A continuación presentamos el caso de una paciente con dolor abdominal inespecífico y pruebas complementarias anodinas en el inicio del cuadro, que evoluciona en las siguientes horas, obligando a la paciente a consultar de nuevo, llegando a precisar una intervención quirúrgica de urgencia. Se trata de un caso que nos obliga a determinar múltiples diagnósticos diferenciales y cómo abordar esta clínica tan frecuente como cambiante. (AU)
Abdominal pain is a nonspecific symptom, common to multiple processes, with a high prevalence in the general population. It represents 15-20% of the reasons for consultation in the Emergency Department1. Most of these pains have a benign etiology, so the initial objective of medical care is to identify those patients whose abdominal pain is due to a serious pathology2. Sometimes, it can have both a fast and torpid evolution and can cause an acute abdomen. Acute abdomen is defined as abdominal pain of recent onset, which requires a rapid and accurate diagnosis due to the possibility that it may lead to urgent surgical treatment. For this, a good history and examination is important, focused on detecting alarm signs and symptoms. If it is not diagnosed and treated properly and early, it can cause consequences such as sepsis, shock, kidney failure, with high mortality3. Below we present the case of a patient with nonspecific abdominal pain and anodyne complementary tests at the beginning of the condition, which evolves in the following hours, forcing the patient to consult again, eventually requiring an emergency surgical intervention. This is a case that forces us to determine multiple differential diagnoses and how to approach this clinic that is as frequent as it is changing. (AU)
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Humanos , Masculino , Anciano , Dolor Abdominal/diagnóstico , Dolor Abdominal/patología , Dolor Abdominal/epidemiología , Diverticulitis , PrevalenciaRESUMEN
Future scientific and technological evolution in many areas of applied mathematics and modern physics will necessarily depend on dealing with complex systems. Such systems are complex in both their composition and behavior, namely, dealing with complex dynamical systems using different types of Duffing equations, such as real Duffing equations and complex Duffing equations. In this paper, we derive an analytical solution to a complex Duffing equation. We extend the Krýlov-Bogoliúbov-Mitropólsky method for solving a coupled system of nonlinear oscillators and apply it to solve a generalized form of a complex Duffing equation.
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In this paper, we obtain the approximate value of 42.9815 arcsec/century for Mercury's perihelion precession by solving both numerically and analytically the nonlinear ordinary differential equation derived from the geodesic equation in Einstein's Theory of Relativity. We also compare our result with known results, and we illustrate graphically the way Mercury's perihelion moves. The results we obtained are applicable to any body that moves around the Sun. We give predictions about the value of the Cosmological Constant. Simple algebraic formulas allow to estimate perihelion shifts with high accuracy.
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In this paper, we approach the phenomenon of criminal activity from an infectious perspective by using tailored compartmental agent-based models that include the social flavor of the mechanisms governing the evolution of crime in society. Specifically, we focus on addressing how the existence of competing gangs shapes the penetration of crime. The mean-field analysis of the model proves that the introduction of dynamical rules favoring the simultaneous survival of both gangs reduces the overall number of criminals across the population as a result of the competition between them. The implementation of the model in networked populations with homogeneous contact patterns reveals that the evolution of crime substantially differs from that predicted by the mean-field equations. We prove that the system evolves toward a segregated configuration where, depending on the features of the underlying network, both gangs can form spatially separated clusters. In this scenario, we show that the beneficial effect of the coexistence of two gangs is hindered, resulting in a higher penetration of crime in the population.
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Crimen , Criminales , HumanosRESUMEN
Pig pregnancy succeeds thanks to a well-coordinated system ruling both maternal immune activation and embryonic antigen tolerance. In physiological pregnancies, the maternal immune system should tolerate the presence of hemi-allogeneic conceptuses from the pre-implantation phase to term, while maintaining maternal defence against pathogens. Allogeneic pregnancies, as after embryo transfer (ET), depict high embryo mortality during the attachment phase, calling for studies of the dynamic modifications in immune processes occurring at the maternal-foetal interface, for instance, of interferon (IFN)-stimulated genes (ISGs). These ISGs are generally activated by IFN secreted by the conceptus during the process of maternal recognition of pregnancy (MRP) and responsible for recruiting immune cells to the site of embryo attachment, thus facilitating cell-antigen presentation and angiogenesis. We performed RNA-Seq analysis in peri-implantation (days 18 and 24) endometrial samples retrieved from artificially inseminated sows (hemi-allogeneic embryos (HAL) group) or sows subjected to ET (allogeneic embryos (AL) group) to monitor alterations of gene expression that could be jeopardising early pregnancy. Our results showed that endometrial gene expression patterns related to immune responses differed between hemi- or allogeneic embryo presence, with allogeneic embryos apparently inducing conspicuous modifications of immune-related genes and pathways. A decreased expression (Pâ¯<â¯0.05; FCâ¯<â¯-2) of several interferon ISGs, such as CXCL8, CXCL10, IRF1, IRF9, STAT1, and B2M, among others was detected in the endometrium of sows carrying allogeneic embryos on day 24 of pregnancy. This severe downregulation of ISGs in allogeneic pregnancies could represent a failure of ET-embryos to signal IFN to the endometrium to warrant the development of adequate immunotolerance mechanisms to facilitate embryo development, thus contributing to elevated embryo death.
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Interferones , Enfermedades de los Porcinos , Animales , Implantación del Embrión , Pérdida del Embrión/metabolismo , Pérdida del Embrión/veterinaria , Transferencia de Embrión/veterinaria , Endometrio/metabolismo , Femenino , Embarazo , PorcinosRESUMEN
In this paper, some exact traveling wave solutions to the integrable Gardner equation are reported. The ansatz method is devoted for deriving some exact solutions in terms of Jacobi and Weierstrass elliptic functions. The obtained analytic solutions recover the solitary waves, shock waves, and cnoidal waves. Also, the relation between the Jacobi and Weierstrass elliptic functions is obtained. In the second part of this work, we derive some approximate analytic and numeric solutions to the nonintegrable forced damped Gardner equation. For the approximate analytic solutions, the ansatz method is considered. With respect to the numerical solutions, the evolution equation is solved using both the finite different method (FDM) and cubic B-splines method. A comparison between different approximations is reported.
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Over the last decade, the release of Wolbachia-infected Aedes aegypti into the natural habitat of this mosquito species has become the most sustainable and long-lasting technique to prevent and control vector-borne diseases, such as dengue, zika, or chikungunya. However, the limited resources to generate such mosquitoes and their effective distribution in large areas dominated by the Aedes aegypti vector represent a challenge for policymakers. Here, we introduce a mathematical framework for the spread of dengue in which competition between wild and Wolbachia-infected mosquitoes, the cross-contagion patterns between humans and vectors, the heterogeneous distribution of the human population in different areas, and the mobility flows between them are combined. Our framework allows us to identify the most effective areas for the release of Wolbachia-infected mosquitoes to achieve a large decrease in the global dengue prevalence.
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Aedes/microbiología , Fiebre Chikungunya/prevención & control , Dengue/prevención & control , Mosquitos Vectores/microbiología , Wolbachia/fisiología , Infección por el Virus Zika/prevención & control , Animales , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/transmisión , Dengue/epidemiología , Dengue/transmisión , Humanos , Control de Mosquitos/economía , Wolbachia/crecimiento & desarrollo , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/transmisiónRESUMEN
In the expanding universe, relativistic scalar fields are thought to be attenuated by "Hubble friction," which results from the dilation of the underlying spacetime metric. By contrast, in a contracting universe this pseudofriction would lead to amplification. Here, we experimentally measure, with fivefold better accuracy, both Hubble attenuation and amplification in expanding and contracting toroidally shaped Bose-Einstein condensates, in which phonons are analogous to cosmological scalar fields. We find that the observed attenuation or amplification depends on the temporal phase of the phonon field, which is only possible for nonadiabatic dynamics. The measured strength of the Hubble friction disagrees with recent theory [Gomez Llorente et al., Phys. Rev. A 100, 043613 (2019)PLRAAN2469-992610.1103/PhysRevA.100.043613 and Eckel et al., SciPost Phys. 10, 64 (2021)SPCHCW2542-465310.21468/SciPostPhys.10.3.064].
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BACKGROUND: Survival of patients with oral squamous cell carcinoma (OSCC) is generally low, with the likelihood of locoregional recurrence or disease progression (LR/DP). Knowledge of prognostic factors for survival is key to achieving an understanding and increased survival. The present study aimed to identify prognostic factors for patients with OSCC, especially the presence of DNA from human papillomavirus (HPV). MATERIAL AND METHODS: Retrospective cohort study including 119 patients with OSCC treated at the National Cancer Institute in Mexico City (2009-2013). Clinical information was obtained from patient records including LR/DP. Formalin-fixed, paraffin-embedded tissues were obtained and used for detecting DNA from different types of HPV. Potential prognostic factors for Overall Survival (OS) were analyzed using the Cox proportional hazards model. RESULTS: After model adjustment, factors associated with longer OS were a pre-treatment platelet count above 400,000/mm3 (HR=0.09, p=0.026) and response to primary treatment (HR=0.26, p=0.001). HPV DNA was present in 23 (19.3%) of the patients and importantly, type 16 found in 19 of them. Although survival of HPV-positive patients was longer, difference was not significant. However, among patients with LR/DP, HPV positivity was significantly associated with increased survival (HR=0.23, p=0.034). Importantly, survival was significantly different for HPV-positive patients with LR/DP > 6 months (HR=0.20, p=0.002), had higher absolute lymphocyte count at start of treatment (HR=0.50, p=0.028) or had local rescue treatment (HR=0.24, p=0.019). CONCLUSIONS: Although HPV positivity was not associated with a longer OS of OSCC patients, a better prognosis was significantly associated with HPV positivity and recurring or progressing disease, particularly with HPV type 16.
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Alphapapillomavirus , Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Neoplasias Orofaríngeas , Infecciones por Papillomavirus , Alphapapillomavirus/genética , Carcinoma de Células Escamosas/patología , ADN Viral , Neoplasias de Cabeza y Cuello/complicaciones , Humanos , Neoplasias de la Boca/patología , Recurrencia Local de Neoplasia , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/diagnóstico , Pronóstico , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/complicacionesRESUMEN
Ultrastable lasers are essential tools in optical frequency metrology enabling unprecedented measurement precision that impacts on fields such as atomic timekeeping, tests of fundamental physics, and geodesy. To characterise an ultrastable laser it needs to be compared with a laser of similar performance, but a suitable system may not be available locally. Here, we report a comparison of two geographically separated lasers, over the longest ever reported metrological optical fibre link network, measuring 2220 km in length, at a state-of-the-art fractional-frequency instability of 7 × 10-17 for averaging times between 30 s and 200 s. The measurements also allow the short-term instability of the complete optical fibre link network to be directly observed without using a loop-back fibre. Based on the characterisation of the noise in the lasers and optical fibre link network over different timescales, we investigate the potential for disseminating ultrastable light to improve the performance of remote optical clocks.
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Pancreatic ductal adenocarcinoma (PDAC) is one of the most intractable and devastating malignant tumors. Epigenetic modifications such as DNA methylation and histone modification regulate tumor initiation and progression. However, the contribution of histone variants in PDAC is unknown. Here, we demonstrated that the histone variant H2A.Z is highly expressed in PDAC cell lines and PDAC patients and that its overexpression correlates with poor prognosis. Moreover, all three H2A.Z isoforms (H2A.Z.1, H2A.Z.2.1, and H2A.Z.2.2) are highly expressed in PDAC cell lines and PDAC patients. Knockdown of these H2A.Z isoforms in PDAC cell lines induces a senescent phenotype, cell cycle arrest in phase G2/M, increased expression of cyclin-dependent kinase inhibitor CDKN2A/p16, SA-ß-galactosidase activity and interleukin 8 production. Transcriptome analysis of H2A.Z-depleted PDAC cells showed altered gene expression in fatty acid biosynthesis pathways and those that regulate cell cycle and DNA damage repair. Importantly, depletion of H2A.Z isoforms reduces the tumor size in a mouse xenograft model in vivo and sensitizes PDAC cells to gemcitabine. Overexpression of H2A.Z.1 and H2A.Z.2.1 more than H2A.Z.2.2 partially restores the oncogenic phenotype. Therefore, our data suggest that overexpression of H2A.Z isoforms enables cells to overcome the oncoprotective barrier associated with senescence, favoring PDAC tumor grow and chemoresistance. These results make H2A.Z a potential candidate as a diagnostic biomarker and therapeutic target for PDAC.