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Due to the energy requirements for various human activities, and the need for a substantial change in the energy matrix, it is important to research and design new materials that allow the availability of appropriate technologies. In this sense, together with proposals that advocate a reduction in the conversion, storage, and feeding of clean energies, such as fuel cells and electrochemical capacitors energy consumption, there is an approach that is based on the development of better applications for and batteries. An alternative to commonly used inorganic materials is conducting polymers (CP). Strategies based on the formation of composite materials and nanostructures allow outstanding performances in electrochemical energy storage devices such as those mentioned. Particularly, the nanostructuring of CP stands out because, in the last two decades, there has been an important evolution in the design of various types of nanostructures, with a strong focus on their synergistic combination with other types of materials. This bibliographic compilation reviews state of the art in this area, with a special focus on how nanostructured CP would contribute to the search for new materials for the development of energy storage devices, based mainly on the morphology they present and on their versatility to be combined with other materials, which allows notable improvements in aspects such as reduction in ionic diffusion trajectories and electronic transport, optimization of spaces for ion penetration, a greater number of electrochemically active sites and better stability in charge/discharge cycles.

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INTRODUCTION AND OBJECTIVES: Bariatric surgery is the most effective treatment for weight loss, with comorbidity control. With low complication rates, the reasons for reoperation are major complications or weight loss failure/weight regain. Nonsurgical problems can also present, such as anemia, dehydration, chronic pain, and malnutrition, among others. Our aim was to analyze the main causes of revisional surgery, reoperation, and hospital readmission, at a specialized bariatric center. METHODS: A retrospective study was conducted on patients that underwent bariatric surgery within the time frame of 2012 and 2019. The baseline analysis included demographic, anthropometric, and perioperative data, as well as a sub-analysis of the main readmission causes and complications. RESULTS: A total of 776 primary surgeries were performed (649 RYGBP, 127 SG, and 10 revisional surgeries), and 99 patients were identified for the study: 10 revisional surgeries, 44 reoperations, and 45 readmissions. The incidence of revisional surgery was 1.2%, reoperation was 5.6%, and readmission 5.8%. Fifty percent of the revisional surgeries were performed due to insufficient weight loss or weight regain; the most frequent causes of reoperation were cholecystitis (38.6%) and internal hernias (9.1%); and the most common causes of readmission were nonspecific abdominal pain (35.5%) and dehydration (24.4%). CONCLUSION: The most frequent causes of postoperative readmission were nonsurgical events, followed by non-bariatric reoperations, and finally revisional surgeries. There was a low incidence of early reoperations. Knowledge of the abovementioned data is important for identifying higher-risk patients, to prevent major complications.

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The interaction between nitrogen-doped graphene defects (N3V1 and N4V2 pyridinic, and N3V1 and N3V3 pyrrolic) and benzene have been investigated by applying density functional theory (DFT), together with the vdW-DF correction. We discovered that only the N3V3 pyrrolic defect is a reactive site (6π-component), forming a cycloadduct with benzene (4π-component) that has energy barriers below 154.38 kJ mol-1 (1.60 eV). The conduction and valence bands (HOMO and LUMO) for N3V3 form a degenerate pair of orbitals at the gamma point, with the same ionization potential (IP) and electron affinity (EA). Likewise, inspection of the orbital symmetries for both systems confirms that these must undergo concerted reactions based on the Woodward and Hoffmann principles of orbital symmetry, with the appropriate orbital occupancies. This is the first time that substitutionally doped graphene has been demonstrated to participate as a 6π-component for cycloaddition reactions with benzene.

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OBJECTIVE: To describe the most common types of fractures in patients under 16 years of age at the forearm level, and to evaluate depending on the level of the fracture, the treatment with better results. MATERIAL AND METHODS: We perform a retrospective analysis to determine the frequency of forearm fractures in patients under 16 years, in the period from January 2013-July 2017. The following diagnoses were entered into the system: forearm fracture, radius fracture, ulnar fracture and bilateral fracture. RESULTS: We included 573 patients: 413 male, 160 females; right affected side: 230, left: 338, bilateral 5. Affected level: 438 distal, 102 mid-shaft and 33 proximal. The peak age of presentation was eight years. The initial treatment was conservative in 92%, followed by closed reduction and percutaneous fixation with 4.71 and 2.4% for open reduction and internal fixation with plates. There was a failed initial treatment at 3.83% when an inadequate reduction was found. DISCUSSION: We found that the treatment of this fractures in our institution is conservative in 92%, closed reduction and percutaneous fixation in 4.71% and open reduction and internal fixation in a 2.4% being The highest prevalence in patients older than 12 years with bilateral mid-shaft fractures.

OBJETIVO: Describir los tipos de fracturas más comunes en pacientes menores de 16 años de edad a nivel de antebrazo y evaluar, dependiendo del nivel de la fractura, el tratamiento con mejores resultados. MATERIAL Y MÉTODOS: Realizamos un análisis retrospectivo para determinar frecuencia de las fracturas de antebrazo en menores de 16 años, en el período de Enero 2013-Julio 2017. Se ingresó en sistema los siguientes diagnósticos: fractura de antebrazo, fractura de radio, fractura de cúbito y fractura radiocubital. RESULTADOS: Se incluyeron 573 pacientes: 413 hombres, 160 mujeres; lado afectado derecho: 230, izquierdo 338, bilateral 5; nivel afectado: 438 distales, 102 medias y 33 proximales. La edad pico de presentación fue a los ocho años. El tratamiento inicial fue conservador en 92%, seguido de reducción cerrada y fijación percutánea con 4.71% y se tuvo 2.4% para reducción abierta y fijación interna con placas. Se tuvo un tratamiento inicial fallido en 3.83% al encontrarse una reducción inadecuada. DISCUSIÓN: Encontramos que el tratamiento de las fracturas en nuestra institución es conservador en 92%, se usa la reducción cerrada y fijación percutánea sólo en 4.71% y sólo se realiza de primera intención la reducción abierta y fijación interna en 2.4% siendo la mayor prevalencia en pacientes mayores de 12 años con fracturas diafisarias medias radiocubitales.

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The dual-purpose bovine system represents 98.4% of the bovine livestock of Veracruz, the main cattle-producing state of Mexico. This system supplies calves to meat companies, a sector in which Veracruz has been the national leader in the last decade. The objective of the present study was to analyze the effect of the altitudinal zonation of farms on livestock technology and productivity in a microbasin of the Gulf of Mexico where small farms predominate. Structured interviews were applied to producers located in three altitudinal zones (at average altitudes of 50, 140, and 450 m, respectively, for lower, middle, and upper zones). Sample size was 135 farms having similar land surface (within a range of 15-22 ha). The results indicated multiple differences among farms located in the three zones. Farms in the middle and lower zones presented higher productive indicators than those in the upper zone. Differences in herd structure and management resulted in important differences in productivity, income, and profits in milk and calf production. We concluded from this study that altitudinal zonation in Veracruz had a clear effect on the differentiation of small farms, which are representative of dual-purpose cattle. The upper zone performs cattle activity under conditions with greater disadvantages in the analyzed region.

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Head and neck squamous cell carcinoma is the sixth most common cancer type worldwide. Also the 5-year survival rate of less than 50 % seems to be lower than other cancer types. There are some reasons behind this high mortality rate; one of them is the lack of knowledge about the biology and genomic instability behind the carcinogenic processes. These biological features could condition the failure of frontline treatment, in which case rescue treatment should be used, representing an overtreatment for the patients. For years many biological factors have been tested as prognostic and predictive factors in relation to treatment with a modest success. To find appropriate tests which could be used in the context of the individualized treatment decision, we have reviewed new biological markers, not only in tumor tissue, but also in normal tissue from head and neck carcinoma patients.

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Thermography is a useful tool since it provides information that may help in the diagnostic of several diseases in a noninvasive and fast way. Particularly, thermography has been applied in the study of the diabetic foot. However, most of these studies report only qualitative information making it difficult to measure significant parameters such as temperature variations. These variations are important in the analysis of the diabetic foot since they could bring knowledge, for instance, regarding ulceration risks. The early detection of ulceration risks is considered an important research topic in the medicine field, as its objective is to avoid major complications that might lead to a limb amputation. The absence of symptoms in the early phase of the ulceration is conceived as the main disadvantage to provide an opportune diagnostic in subjects with neuropathy. Since the relation between temperature and ulceration risks is well established in the literature, a methodology that obtains quantitative temperature differences in the plantar area of the diabetic foot to detect ulceration risks is proposed in this work. Such methodology is based on the angiosome concept and image processing.

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A new connection between maximum-power Curzon-Ahlborn thermal cycles and maximum-work reversible cycles is proposed. This linkage is built through a mapping between the exponents of a class of heat transfer laws and the exponents of a family of heat capacities depending on temperature. This connection leads to the recovery of known results and to a wide and interesting set of results for a class of thermal cycles. Among other results it was found that it is possible to use analytically closed expressions for maximum-work efficiencies to calculate good approaches to maximum-power efficiencies. Behind the proposed connection is an interpretation of endoreversibility hypothesis. Additionally, we suggest that certain reversible maximum-work cycles depending on working substance can be used as reversible landmarks for FTT maximum-power cycles, which also depend on working substance properties.

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Satellite glia cells (SGCs), within the dorsal root ganglia (DRG), surround the somata of most sensory neurons. SGCs have been shown to interact with sensory neurons and appear to be involved in the processing of afferent information. We found that in rat DRG various N-methyl-D-aspartate receptor (NMDAr) subunits were expressed in SGCs in intact ganglia and in vitro. In culture, when SGCs were exposed to brief pulses of NMDA they evoked transient increases in cytoplasmic calcium that were inhibited by specific NMDA blockers (MK-801, AP5) while they were Mg²âº insensitive indicating that SGCs express functional NMDAr. The percentage of NMDA responsive SGCs was similar in mixed- (SGCs plus neurons) and SGC-enriched cultures. The pattern of the magnitude changes of the NMDA-evoked response was similar in SGCs and DRG neurons when they were in close proximity, suggesting that the NMDA response of SGCs and DRG neurons is modulated by their interactions. Treating the cultures with nerve growth factor, and/or prostaglandin E2 did not alter the percentage of SGCs that responded to NMDA. Since glutamate appears to be released within the DRG, the detection of functional NMDAr in SGCs suggests that their NMDAr activity could contribute to the interactions between neurons and SGCs. In summary we demonstrated for the first time that SGCs express functional NMDAr.

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Cervical carcinoma is the third most common cancer in women worldwide. The programs developed for early detection have made that most patients are diagnosed in early stages. Treatment for those patients consists of conservative techniques as surgery or radical radiotherapy; however, the decision between those two therapies is still controversial. Even though in many cases this decision varies according to classical associated risk factors (i.e. tumor stage or age), in the clinical practice, a significant number of patients treated by surgery also receive post-surgery radiotherapy, with the consequent over-treatment and toxic effects. Since response to treatments is conditioned by individual factors, the use of new biological markers as novel predictive factors for both tumor and normal tissues could help clinicians to choose the best treatment schedule for each patient individually. Based on the experience of our institution, we have reviewed the new biological markers in cervical carcinoma patients treated by radiotherapy.

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BACKGROUND: Colon transverse volvulus is an uncommon pathology which is associate with alterations of the colonic motility, mental disorders and congenital anomalies of the fixation of the colon sistem. Up to 1994, 72 cases has been reported in world-wide literature. AIM: To report a case of colon transverse volvulus and the treatment. CASE REPORT: A female 46 years old who show intense abdominal pain 2 days of evolution. The physical exploration show important abdominal distension and pain in left inferior quadrant. The Rx of abdomen with gas absence in rectal descendent colon and ampula with level and important distension of proximal colon. Colonoscopic study with impossibility to advance endoscopy throw colon transverse by zone of stenosis, wasn't made a contrast study, underwent laparotomy of urgency, it was done right hemicolectomy and ileocoloanastomosis with good evolution and given of discharge fourth postsurgical day. CONCLUSIONS: This possibility is due to have in mind diagnoses, the treatment is surgical secondary to a high index of recidivate, nevertheless recommends the colonoscopy study accomplishment in order to discard obstructive injuries mainly cancer.

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Ochenta y tres pacientes con artirtis reumatoidea y que recibían diclofenac sódico para el control de su enfermedad fueron seleccionados para ingresar a un estudio doble-ciego placebo controlado de 4 semanas de duración, recibiendo la mitad de ellos 50 ml de diclofenac sódico tres veces al día, y la otra mitad 50 mg de Diclofenac sódico tres veces al día más placebo. El propósito del estudio fue evaluar el efecto del misoprostol sobre las lesiones erosivas o sangrantes, dándoseles un puntaje de acuerdo a nuestro protocolo de investigación. Los pacientes que recibieron misoprostol mostraron un descenso significativo en las lesiones erosivas (112 a 31, p menor de 0.05) que al compararlas con los que recibieron placebo (123 a 60) también fué estadísticamente significativa (p menor de 0.05). No se observaron diferencias significativas en relación con las lesiones sangrantes al comparar los dos grupos. Cinco pacientes desarrollaron úlceras para el final de estudio (4 antrales y una duodenal), 4 de ellos recibieron placebo. Hubo un discreto efecto atenuante de la acción antiinflamatoria del diclonac sódico en nuestros pacientes. Se concluye que el misoprostol disminuyó significativamente las lesiones erosivas en los pacientes reumatoideos y protegió contra el efecto ulcerogénico del diclofenac sódico

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Erosions at the antero-superior angles of C4 and C5 developed in 11 patients (22%) with rheumatoid arthritis of less than one year's duration were followed-up over a 10-year period. These erosions do not appear to have been described before.

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