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In electrocatalysis we seldom think about the competing direct reduction reactions that may happen alongside catalytically mediated reduction‐ with direct redox chemistry often happening slower but in competition with, catalysis. One class of compounds of interest from this perspective are iron sulfides. In addition to being structurally similar to many metalloproteins, iron sulfides are also among nature's strongest chemical reductants and reported to act as catalysts for key chemical reactions including proton, nitrite, and nitrate reduction. It is important that iron sulfides can act as catalysts because they are also strong enough reductants to mediate some of the same reactions directly. This is paradoxical because in order to be a catalyst for reduction, an iron sulfide cannot also be oxidised. To investigate this phenomenon further, we assembled a test set of iron sulfides spanning both amorphous iron sulfide (FeSam) as well as the crystalline iron sulfides greigite, pyrite, and troilite. These were used to explore the relationship between direct reduction and catalysis of a reduction reaction with a secondary electron source, NO2− was chosen as a test substrate. The trends in direct reduction followed the least stable material (FeSam) to the most stable material (FeS2). Of the phases studied, troilite (FeS) showed the largest difference between direct and catalytic reduction, however amorphous iron sulfide showed the greatest selectivity for NH3/NH4+ production as both a direct reductant and a catalyst. [ABSTRACT FROM AUTHOR]

Objective. To determine the prevalence of classic stereotypies in Thoroughbred racehorses at the Club Hípico Concepción (CHC) in Chile and its association with sex and age. Materials and methods. The entire population of resident horses at the CHC was studied (n=341). Each horse trainer (n=23) was asked for the name, sex and age of the horses under his/her supervision. After that, all the animals were continuously observed inside their stalls for 8 hours by only one person, to record the absence or presence of classic stereotypies (cribbing, weaving, stall-walking). To analyze the data, the animals were divided by sex into 3 groups: stallions, geldings and mares. According to age, they were divided into 2 groups: < 5 years old and 5 years old or more. Descriptive statistics were used and association was tested using the chi square test using p≤0.05. Results. 13.2% of all CHC's horses displayed stereotypies: cribbing (4.99%), weaving (2.93%) and stall-walking (5.28%). No association was found between the presence of stereotypies and sex or age. Conclusions. Thoroughbred race horses at the CHC showed a high prevalence of classic stereotypies, especially stall-walking. [ABSTRACT FROM AUTHOR]

Keywords: Redox; Iron Sulfide; Electron transfer; Electrocatalysis EN Redox Iron Sulfide Electron transfer Electrocatalysis 1 1 1 06/24/22 20220622 NES 220622 B The Cover Feature b shows two different natural sceneries where iron sulfides play a key role in mediating chemical reductions. Redox, Iron Sulfide, Electron transfer, Electrocatalysis. [Extracted from the article]

Abstract: Colombia strives to have enough firm capacity available to meet unexpected power shortages and peak demand; this is clear from mechanisms currently in place that provide monetary incentives (in the order of nearly US$ 14/MWh) to power producers that can guarantee electricity provision during scarcity periods. Yet, wind power in Colombia is not able to currently guarantee firm power because an accepted methodology to calculate its potential firm capacity does not exist. In this paper we argue that developing such methodology would provide an incentive to potential investors to enter into this low carbon technology. This paper analyzes three methodologies currently used in energy markets around the world to calculate firm wind energy capacity: PJM, NYISO, and Spain. These methodologies are initially selected due to their ability to accommodate to the Colombian energy regulations. The objective of this work is to determine which of these methodologies makes most sense from an investor''s perspective, to ultimately shed light into developing a methodology to be used in Colombia. To this end, the authors developed a methodology consisting on the elaboration of a wind model using the Monte-Carlo simulation, based on known wind behaviour statistics of a region with adequate wind potential in Colombia. The simulation gives back random generation data, representing the resource''s inherent variability and simulating the historical data required to evaluate the mentioned methodologies, thus achieving the technology''s theoretical generation data. The document concludes that the evaluated methodologies are easy to implement and that these do not require historical data (important for Colombia, where there is almost no historical wind power data). It is also found that the Spanish methodology provides a higher Capacity Value (and therefore a higher return to investors). The financial assessment results show that it is crucial that these types of incentives exist to make viable wind projects in Colombia at US$ 2000/installed kW. With the absence of these incentives the Project''s NPV would be negative before and after-taxes. Additionally, it is demonstrated that wind power projects would only be viable in Colombia if the price of CERs is at least US$ 20/CO2e ton. Furthermore, it is concluded that income tax exemptions are not enough to encourage wind power development in Colombia. [Copyright &y& Elsevier]

Keloids or hypertrophic scars can appear secondarily to piercings, trauma, bums, surgical procedures, etc. as it has been described. One of the theories says that they are a result of an altered process, in which collagen synthesis by fibroblasts is excessive; but the etiology remains unknown. Many and varied treatment have been described but the recurrence of the disease is a rule. We present a case in which a patient had a right earlobe keloid. It was treated several times and in several manners, with recurrence of the disease. We treated it by means of surgical resection and 5% lmiquimod cream. The patient is disease ‘free’ 6 months after surgery. [ABSTRACT FROM AUTHOR]

Quartz sand columns and sand-filled microscope flow cells were used to investigate the transport characteristics of the clay colloid laponite, and a biofilm-forming bacterium, Pseudomonas aeruginosa SG81. Separate experiments were performed with each particle to determine their individual transport characteristics in clean sand columns. In a second set of experiments, bacterial biofilms were formed prior to introduction of the clay colloids. In the independent transport experiments, bacteria and laponite each conformed to known physicochemical principles. A sodium chloride concentration of 7×10-2 M caused complete retention of the laponite within the sand columns. P. aeruginosa SG81 was generally less influenced by ionic strength effects; it showed relatively low mobility at all ionic strengths tested and some (albeit reduced) mobility when introduced to the columns in 1 M NaCl, the highest concentration tested, but nevertheless showed reproducible trends. Under conditions favourable to laponite retention and biofilm stability (7×10-2 M NaCl), laponite suspensions were able to remobilise a portion of the attached bacterial biomass. At low ionic strength, the profile of laponite elution was also altered in the presence of a P. aeruginosa biofilm. These observations suggest that while a reduction in ionic strength has a dominant influence on the mobilisation of biological and inorganic colloids, the presence of laponite and biomass can have a distinct influence on the mobility of both types of colloids. Since these events are likely to occur in subsurface environments, our results suggest that colloid–biofilm interactions will have implications for colloid–bound contaminant transport and the remobilisation of pathogens. [Copyright &y& Elsevier]

Living donor liver transplantation is a complex and challenging procedure. The surgeon needs to guarantee maximum safety for the donor, as well as the best quality of the graft for the recipient. For this reason, the implementation of mini-invasive surgery has been slow in this area. However, in the last 10 years, due to the advances in laparoscopic liver surgery, the interest of some highly specialized groups has increased in incorporating mini-invasive surgery into donor surgery, mainly in pediatric living donor liver transplantation. The favorable results obtained in this field, have even led to turn this procedure, into the technique of choice for pediatric living donor liver transplantation. Nevertheless, this procedure is even more challenging for adult-to-adult living donor transplantation. To meet the volumetric criteria of an adult, a complete hepatectomy of right or left lobe is mostly required. This surgery is of greater complexity and risk for the donor, so its indication by minimally invasive approach is limited to high-volume centers with preparation, both in laparoscopy and liver transplants. In this report we seek to present our surgical technique and initial experience with the first pure laparoscopic right hepatectomy for adult-to-adult living donor liver transplantation carried out in Chile. [ABSTRACT FROM AUTHOR]

Introduction: Actinomycosis is a rare chronic infection caused by bacterias of the genus Actinomyces sp. Pelvic involvement is one of its most infrequent forms and in many cases it is related to the use of a longstanding intrauterine device or a previous surgery. Like other rare diseases, the infection is known as "the great imitator" because of its varied form of presentation and its particular behavior, which can simulate a neoplasm. The treatment is fundamentally medical with good results. Case Report: We present the case of a patient who presented with a rectal tumor but that turned out to be Actinomycosis. The diagnosis was made based on the Gram stain, the clinical presentation and the history of an intrauterine device left for more than 25 years. It was subsequently corroborated by pathological anatomy and successfully treated with antibiotics for an extended period. Conclusion: Although actinomycosis is an infrequent pathology, it should be considered in the differential diagnosis of patients who present with tumors of the pelvis. An active diagnostic attitude and a high index of suspicion are fundamental for the timely, safe and effective treatment of this disease. [ABSTRACT FROM AUTHOR]

Background: This paper studies the effect of the variability in fiscal revenues (induced by volatility in natural resource prices) on public saving in the case of natural resource dependent economies. Methodology: A theoretical model is used to extend the work of Van der Ploeg and Venables (2011). Later, an econometric analysis is performed with data from panels of two different data samples. We find evidence in favor of the hypothesis. Results: It is found that the greater the variance in fiscal revenues the greater should be the level of net fiscal assets, due to precautionary saving. Conclusions: The volatility of fiscal revenues in countries exposed to commodities leads governments to precautionary savings and to have higher levels of fiscal savings. [ABSTRACT FROM AUTHOR]

Introduction: Approximately 5-10% of global cancer has a genetic base. Nowadays it is possible to identify those who have a genetic predisposition for breast cancer, so they can be treated in short term. Objectives: Evaluate how useful is prophylactic surgery on Hereditary Breast cancer Syndrome. Materials and methods: This investigation is a literature review of different research papers from electronic databases such as Scientific Electronic Library Online (SciELO), MedLine-PubMed and UpToDate. The research was made with clinical queries and MeSH terms, specially focused on Hereditary Breast cancer Syndrome. Results: This research shows that prophylactic bilateral mastectomy (PBM) decreases 90% risk of developing breast cancer in BRCA1 and BRCA2 carriers. On the other hand, Salpyngo-oophoferectomy (SO) technique decreases around 53% chances of breast cancer, depending on the associated mutation. Conclusion: Prophylactic surgery has shown an important role decreasing the risk on Hereditary Breast cancer Syndrome. So on, in cases of BRCA1 and BRCA2 carriers we suggest to perform prophylactic surgery. [ABSTRACT FROM AUTHOR]

Introduction: Living donor left lateral sectionectomy is a well-established alternative in cadaveric donor pediatric liver transplantation. This procedure has proven to be safe and reproducible. However, laparoscopic approach is still under development and evidence of its feasibility is limited. Aim: The aim of this article is to present the surgical technique and postoperative outcomes of the cases of laparoscopic left lateral sectionectomy performed in this center. Materials and Method: A retrospective, observational, single center study was conducted in Hospital del Salvador. From 04/2015 - 01/2021 laparoscopic left lateral sectionectomy was offered for donor surgery. We present the surgical technique, perioperative care, and early postoperative outcomes in donors. Results: This series includes 36 patients, 25 (69%) of them were males. A total of 31 (86%) donors were mother or father of the recipient. Median age of donors was 30 years (19-45), median operative time was 360 min (240-480). All the patients underwent laparoscopic left lateral sectionectomy. Conversion was necessary in one case due to difficult management of a venous bleeding. Clavien-Dindo Morbidity III, in one patient who required endoscopic retrograde cholangiopancreatography due to an early bile leak. Median hospitalization was 4 days (3-14). There was no mortality. Conclusion: Laparoscopic left lateral sectionectomy has proven to be safe and reproducible. This technique has evolved from an innovative procedure to become the current standard of practice in our center, with excellent results in terms of morbidity and mortality. [ABSTRACT FROM AUTHOR]

The human epidermal growth factor receptor 2 (ERBB2, HER2 or HER2/neu) is a transmembrane tyrosine kinase receptor that is overexpressed in approximately 20% of breast cancers. The use of the anti-HER2 monoclonal antibodies Pertuzumab and Trastuzumab in association with chemotherapy has achieved a higher percentage of pathologic complete response (pCR) than conventional chemotherapy. The purpose of our study was to identify factors that could affect the therapeutic response of patients with breast cancer and HER2 overexpression treated with cytotoxic chemotherapy plus double HER2 blockade in neoadjuvant setting at Fundación Arturo López Pérez (FALP). A case–control study was designed to evaluate the effect of clinical and histopathological variables on the response to neoadjuvant therapy. Ninety-four women with non-metastatic breast cancer and HER2 overexpression received neoadjuvant combination chemotherapy with Trastuzumab and Pertuzumab at FALP during the period 2017–2020. Seventy percent of patients achieved pCR, and in the group of hormone receptor negative patients, 89% of patients achieved pCR. Different variables were analysed trying to look for clinicopathological predictors of complete response. This study provides us with real-world data on the efficacy of using this treatment combination in our population of HER2-overexpressing breast cancer patients. [ABSTRACT FROM AUTHOR]

Introduction: Approximately 5-10% of global cancer has a genetic base. Nowadays it is possible to identify those who have a genetic predisposition for some cancers, so they can be treated in short term. Objectives: Evaluate how useful is prophylactic surgery on hereditary Medullary Thyroid Cancer. Materials and methods: This investigation is a literature review of different research papers from electronic databases such as Scientific Electronic Library Online (SciELO), MedLine-PubMed and UpToDate. The research was made with clinical queries and MeSH terms, specially focused on hereditary Medullary Thyroid Cancer. Results: This research shows that prophylactic Thyroidectomy with cervical lymph node resection is the only effective and curative treatment for hereditary Medullary Thyroid Cancer. Conclusions: Prophylactic surgery has proof an important role decreasing the risk on Hereditary Thyroid cancer Syndrome and in RET carriers surgery is considered a must. [ABSTRACT FROM AUTHOR]

Introduction: The use of breast expander, prior to the final prosthetic reconstruction, is not exempt from complications. They not only relate to the presence of peri-operative radiation therapy, or patient-related issues; but also related to the muscle integrate coverage of the breast expander. Material and methods: Retrospective review of patients undergoing deferred breast reconstruction using a modification of the technique of sub muscular pocket closing with oxidized regenerated cellulose NU-KNIT™ for the breast expander. Between January 1, 2014 and December 31, 2015 one plastic surgeon (J.V.), from the Breast Pathology Unit at Clínica Alemana de Santiago, performed reconstruction surgeries with this technique in 31 patients. In the present article, the technique modification, demographic data, histological data and the complications which arose during the expansion phase of the same, will be described. Results: 40 breast reconstructions were performed in 31 patients. 11 seromas (27.5% of total expanders), 2 sufferings of skin flap wound dehiscence (5% expanders) and 1 wound infection (2.5% of expanders) were presented. Two patients required surgical debridement due to surgical dehiscence and infection. One patient required explantation of the expander (2.5% of total expanders). Discussion: The modification of the surgical technique represents a safe and reproducible alternative to achieve a complete closure of the muscular pocket and thus a complete coverage of the expander, consequently; avoiding some of the secondary complications drawn from an insufficient coverage of the expander. [ABSTRACT FROM AUTHOR]

Introduction: Drug induced liver injury (DILI), is a drug hepatotoxicity, with low incidence. However represents the most common cause of death secondary to acute liver failure. Assertive diagnosis and early treatment is important to avoid adverse results. Case report: A 73-year-old woman, with arterial hypertension and cholecystectomy, who suffered community acquired pneumonia with atypical presentation, was treated with clarithromycin 500 mg twice a day. She manifested jaundice, choluria, hipocholia and fatigue after the fourth day in treatment. Additional, physical examination: at palpation showed right and upper abdominal pain, and hepatomegaly. During the emergency room, laboratory tests showed significant alterations in liver function. Total leukocyte count 9020 with 8% eosinophils. Abdominal ultrasound was negative for biliary obstruction. During hospitalization, markers for autoimmune liver disease were non pathological, and viral serologies (Hepatitis A, B, C viruses, Epstein Barr, Cytomegalovirus and Human immunodeficiency virus) were negative. Biliary obstruction was negative according Magnetic resonance cholangiopancreatography. Liver biopsy showed "drug induced liver injury". Clarithromycin was suspended, and the patient achieved clinical improvement and she was discharge at the 7th day. Discussion: Clarithromycin is an antibiotic widely used for several bacterial infections, capable of induced hepatotoxicity. Diagnosis of DILI is difficult, that requires high index of clinical suspicion. Clinical manifestations, eosinophilia and diferential diagnoses are key for an assertive diagnosis. [ABSTRACT FROM AUTHOR]

Pylephlebitis is a rare complication of intra-abdominal infection involving septic thrombosis of the portal system. If the splenic vein is compromised, this can lead to a splenic abscess, an extremely rare complication of pylephlebitis. The pathophysiology behind these clinical entities remains unclear. In both cases, symptoms are highly nonspecific and include fever, malaise and abdominal pain. Here, we discuss a case in which a patient develops both pylephlebitis and a subsequent splenic abscess following a transrectal prostate biopsy. Diagnosis was made by computerized tomography scan; the treatment included broad spectrum antibiotics and laparoscopic splenectomy, after which the patient made a full recovery. [ABSTRACT FROM AUTHOR]

In this work, we show a simple way to functionalize tungsten oxide nanowires (WO3-NWs) using a saturated palladium chloride (PdCl2) solution deposited by a drop-casting method. WO3-NWs were synthesized by close-spaced chemical vapor deposition (CSVT). The morphological and structural characterizations showed that the diameters of WO3-NWs are in the range from 50 to 200nm with lengths above 10μm, and correspond to the orthorhombic phase of WO3, respectively. The sensor was fabricated using the WO3-NWs and tested with hydrogen and volatile organic compounds (VCO's). A comparative study was done on the sensing performance, before and after the Palladium functionalization of the WO3-NWs, considering a wide range of gas concentrations and moderate operating temperatures (100–400°C). The results show that this simple functionalization process significantly increases the sensor sensitivity and reduces the time constants. In addition, it has been shown that at 300°C the decorated sensor becomes more selective to hydrogen and xylene for all concentrations considered in this research. Finally, the mechanisms involved in improving the gas sensing properties of WO3-NWs functionalized with Palladium are discussed. [ABSTRACT FROM AUTHOR]

Introduction. The first place in Mexico with specialized service in the treatment of patients with burns took place in 1945. Actually only the public health care services have centers with special units for the patient with burns. The burn unit in Mexico's Central Military Hospital started working in 1998. It has six individual cubicles, with a continuous monitorization system for each one, a special place for wound treatment and an operating room. Besides it counts with the participation of a multidisciplinary team for the treatment of burned patients. Material and method. A descriptive, cross-sectional, retrospective study was made from June 1998 to December 2006. The information of patients' registry was obtained from the bum Unit. The count of each one of the individuals for each one of the groups was made by means of wrangle system. Results. In the period comprehended between 1998 and 2006, 397 patients were treated, with an average of almost 50 patients per year. 65.23% were males and 34.7% were females. The most common etiology was scalding 45.2.5%, followed by fire injury 41.13%, electricity 10.96%, chemical 1.5% and other types (0.51%). Ten patients died in this period (2.51%), with the diagnosis of massive bum as the main cause. The average hospital stay was 14.99 days per patient. Conclusion. The clinical experience reported in our institution demonstrates that Mexico's Central Military Hospital has a special bum unit, with special equipment, infrastructure and medical specialists that provide high quality attention for the patients with bums. Our types of treatment and results are similar to the ones reported in national and international literature. [ABSTRACT FROM AUTHOR]

This work describes different microhistological techniques, to study wild and domestic herbivore diets. The methods to obtain epidermal tissue were applied to the main vegetal species of the Mediterranean and high plain pastures, to evaluate the degree of resolution in their identification and characterization. In most grasses and grass-like species, the epidermal tissue was obtained easily by scraping without complications, identifying species based on specific characteristics of the cellular wall, cell size and shape, presence and shape of cork and silica cells, and presence and shape of trichomes. In some poaceas with very hard epidermis, prior treatment with ether and nitric acid was necessary before scraping. In wood and wide leaf herbaceous species, the diafanization method was the most efficient way to obtain the epidermis, and species identification was based on cell and trichome shape, and in some cases, on stomas shape, but, in some genera, species differentiation was not possible. The microhistological technique proved to be a useful tool to obtain epidermis of plant species, being an accurate method to identify and characterize this structure. Some wide leaf herbaceous species showed a strong sensitivity to diafanization, so this technique should be improved. [ABSTRACT FROM AUTHOR]