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Acetylsalicylic acid (ASA) synthesized in the practical classes of experimental organic chemistry is generally discarded after the classes. Thus, the objective of this work is to find an alternative application for ASA and to promote awareness about the recycling of chemicals in educational and research environments. In addition, it explores the subsequent application of this synthesized ASA in the creation of powdered developers for latent fingerprints. The adopted methodology included the recrystallization of the previously synthesized ASA, followed by the development of three distinct formulations of powdered developers, which include ASA, lignin, and methylene blue. Subsequently, these powders were used to identify latent fingerprints, demonstrating that they are promising substances for such applications.

Photodynamic therapy (PDT) is a clinically proven advancement in cancer treatment that has progressively gained consideration as a possible method of cancer treatment over time. This therapy, which involves the administration of a photosensitizing drug before activation of the drug with light from a source such as a laser to produce a cytotoxic effect, is minimally invasive and could increase the life expectancy of cancer patients. Cancer has been a major threat to human health, and it affects the quality of life of cancer patients as it is one of the topmost causes of mortality worldwide. The burden of cancer has been projected to increase to 2.1 million new cases and 1.4 million deaths in Africa by 2040. It is therefore expedient to put in more effort in proffering preventive measures, more efficient treatments, and possible cures for this disease. Recent studies have shown that many types of tumors can be destroyed using PDT. Tumor cells are destroyed via apoptosis, necrosis, and autophagy through some mechanisms in PDT. The successful outcome of this therapy depends greatly on three components which are photosensitizer (PS), light and molecular oxygen. Out of these three, photosensitizer is the most essential. Among the characteristics of a potent PS are the presence of a tetrapyrrole structure and the ability to initiate a photodynamic reaction when irradiated typically at a wavelength between 600 nm and 800 nm, although some PS can function effectively outside this range. This review highlights the effectiveness of PDT in the treatment of cancer and emphasizes the importance of PS, with more focus on those derived from natural sources, in determining the outcome of the therapy.

In this initial study, the impact of thermosonication as an alternative to the traditional fusion in Brazilian cheese spread (Requeijão Cremoso) manufacture was investigated. The effect of ultrasound (US) power was evaluated considering various aspects such as gross composition, microstructure, texture, rheology, color, fatty acid composition, and volatile compounds. A 13 mm US probe operating at 20 kHz was used. The experiment involved different US power levels (200, 400, and 600 W) at 85 °C for 1 min, and results were compared to the conventional process in the same conditions (85 °C for 1 min, control treatment). The texture became softer as ultrasound power increased from 200 to 600 W, which was attributed to structural changes within the protein and lipid matrix. The color of the cheese spread also underwent noticeable changes for all US treatments, and treatment at 600 W resulted in increased lightness but reduced color intensity. Moreover, the fatty acid composition of the cheese spread showed variations with different US power, with samples treated at 600 W showing lower concentrations of saturated and unsaturated fatty acids, as well as lower atherogenicity and thrombogenicity indexes, indicating a potentially healthier product. Volatile compounds were also influenced by US, with less compounds being identified at higher powers, especially at 600 W. This could indicate possible degradation, which should be evaluated in further studies regarding US treatment effects on consumer perception. Hence, this initial work demonstrated that thermosonication might be interesting in the manufacture of Brazilian cheese spread, since it can be used to manipulate the texture, color and aroma of the product in order to improve its quality parameters.

Category: Ankle; Other Introduction/Purpose: The Invision talar component was launched in 2018 as a revision total ankle arthroplasty (TAA) specific option geared towards avoiding further subsidence when poor talar bone stock is present. Due to the recency of the market- availability of the Invision, studies evaluating the efficacy of the implant, even in the short-term, are lacking. Thus, the purpose of this study was to present the early-term outcomes of a series of patients undergoing revision TAA with the use of the Invision talar component. Methods: This was a single-center, retrospective review of 28 patients undergoing revision TAA with the Invision talar component and Inbone II tibial component (Wright Medical; Memphis, Tennessee) performed between 2007 and 2022. Mean follow-up was 1.3 ± 0.93 years. Data on patient preoperative characteristics, postoperative complications, and survivorship were collected. The primary outcome measures were time to major complication, reoperation, and infection. Results: The most common concurrent procedures performed with revision TAA with the Invision talar component were gastrocnemius recession (n=14, 50%), subtalar arthrodesis (n=3, 10.7%) and cotton osteotomy (n = 1, 3.6%). The mean preoperative coronal deformity off the tibia was 4.07 ± 3.06 degrees for varus and 3.67 ± 4.36 degrees for valgus deformities, respectively, and postoperatively, was 1.67 ± 2.16 degrees for varus and 2.00 ± 3.48 degrees for valgus. The mean preoperative coronal plane deformity off the talus was 4.83 ± 6.68 degrees for varus and 4.22 ± 4.21 degrees for valgus, respectively, and postoperatively, was 1.23 ± 2.45 degrees for varus and 2.32 ± 3.93 degrees for valgus. The survivorship from any complication, major complication, reoperation, and infection is shown in Table 2. Conclusion: In a series of 28 patients undergoing revision TAA with the Invision talar component and Inbone II tibial component, we demonstrate a survivorship of 92.7% at 1-year follow up. The Invision appears to have a reasonable safety profile in this non- designer series. The implant compares favorably with others utilized in the revision TAA setting at the early-term, but further studies evaluating mid-and long-term outcomes are required to fully assess the efficacy of the Invision.

Category: Ankle Arthritis Introduction/Purpose: As total ankle arthroplasty (TAA) rises in popularity nationwide, the incidence of major complications and need for revision TAA will continue to increase. A better understanding of the ability to durably correct deformity and improve patient reported outcomes (PROs) in the TAA revision setting is paramount for surgeons facing the impending wave of failed TAA. Thus, the purpose of this study was to present the largest single-center case series of revision TAA to date and to evaluate improvement in PROs and maintenance of correction of coronal plane deformity in patients undergoing this procedure. Methods: This was a single-center, retrospective review of 87 revision TAAs performed between 2007 and 2022. Reoperations for cyst formations only or without metallic component exchange were excluded. The two most common implants used for revision TAA were Inbone II (n=65) and Inbone I (n=14). Mean follow-up was 2.8 ± 2.9 years. Data on patient preoperative characteristics, concurrent procedures, and postoperative complications were collected. The primary outcome measures were time to major complication, reoperation, and infection. Secondary outcomes included PROs and correction of coronal plane deformity measured from both the tibial plafond and talar articulating surface from pre- to post-operatively. Cox regression analyses were performed to compute survivorship. Results: The most common concurrent procedures performed concomitantly with revision TAA were gastrocnemius recession (n=31, 35.6%), subtalar arthrodesis (n=18, 20.7%), and talonavicular arthrodesis (n=5, 5.7%). Mean preoperative coronal plane deformity measured off both the tibial plafond and talar articular surface improved after revision TAA. 1- and 5-year survivorship from major complication, reoperation, and infection is shown in Table 2. Fourteen patients underwent subsequent revision, including TAA (n= 6, 6.9%), arthrodesis (n= 4, 4.6%), below-the-knee amputation (n= 2, 2.3%), or implantation of an antibiotic spacer (n= 2, 2.3%). At one-year postoperatively, mean VAS pain score, SF36, and AOFAS Hindfoot score was 18.2 ± 16.0, 73.0 ± 13.3, and 68.8 ±:9.3, respectively, representing an improvement in PROs after revision TAA. Conclusion: In the largest single-center series of patients undergoing single or double component exchange revision TAA, we demonstrate durable improvements in coronal plane deformity measured off both the tibial plafond and talar articular surface. We also noted 63.0% survivorship with regards to reoperation and improvements in average PROs across the cohort. Overall, revision TAA is a successful procedure, but is associated with higher failure rates at 5 years than primary TAA.

Se analizan los factores intrínsecos y extrínsecos que controlaron la preservación del saurópodo rebaquisáurido Katepensaurus goicoecheai, procedente de la Formación Bajo Barreal (Grupo Chubut-Cretácico Superior) en el centro-sur de Chubut, cuenca del Golfo San Jorge, Patagonia central, Argentina. Los restos se preservaron en un depósito de desbordamiento no canalizado, de geometría lobulada, de 30 cm de potencia y vinculado a canales fluviales arenosos. Litológicamente está integrado por areniscas gruesas con abundante matriz pelítica y tobácea, que permiten caracterizarlo como un flujo hiperconcentrado. Los elementos recuperados, que corresponden principalmente al esqueleto axial, yacían sobre depósitos pelíticos de una planicie de inundación distal mal drenada y fueron parcialmente cubiertos por el lóbulo de desbordamiento, quedando estructuras expuestas que fueron intensamente erosionadas. Los restos se encontraron incompletos, desarticulados y exhibiendo evidencias de una exposición subaérea prolongada. Fueron poco movilizados por procesos hidráulicos y reorientados de forma normal a la dirección del desbordamiento. La dispersión lateral muestra grupos de huesos producto de entrampamientos hidráulicos causados por los restos de mayor tamaño en la parte central del lóbulo y los más pequeños hacia los laterales acorde a la distribución de energía del depósito. La escasa potencia del desbordamiento no sepultó completamente los restos. Finalmente, un nuevo desbordamiento cubrió completamente los materiales. La acumulación de huesos de Katepensaurus sería una concentración ósea residual y representa una acumulación parautóctona de origen sedimentológico.

This work presents a multi-parameter optical fiber monitoring solution applied to an underground power distribution network. The monitoring system demonstrated herein uses Fiber Bragg Grating (FBG) sensors to measure multiple parameters, such as the distributed temperature of the power cable, external temperature and current of the transformers, liquid level, and intrusion in the underground manholes. To monitor partial discharges of cable connections, we used sensors that detect radio frequency signals. The system was characterized in the laboratory and tested in underground distribution networks. We present here the technical details of the laboratory characterization, system installation, and the results of 6 months of network monitoring. The data obtained for temperature sensors in the field tests show a thermal behavior depending on the day/night cycle and the season. The temperature levels measured on the conductors indicated that in high-temperature periods, the maximum current specified for the conductor must be reduced, according to the applied Brazilian standards. The other sensors detected other important events in the distribution network. All the sensors demonstrated their functionality and robustness in the distribution network, and the monitored data will allow the electric power system to have a safe operation, with optimized capacity and operating within tolerated electrical and thermal limits.

The use of anabolic androgenic steroids is largely restricted worldwide since they are associated with innumerous side effects and health damage. However, apprehensions of formulations of anabolic agents have been extensively increasing throughout the world, making their analysis a common task in the forensic field. In this sense, a set of three experiments was developed and applied to undergraduate students of Forensic Chemistry dealing with visual inspection of apprehended formulations of anabolic androgenic steroids as well as chemical identification by Infrared Spectroscopy and Gas Chromatography-Mass Spectrometry. Moreover, the classroom evaluated the extraction of steroidal active ingredients by ultrasonic and microwave-assisted extraction. The experimental procedures allied with the theory behind these topics provided an important background to the students on distinct extraction methods and analytical techniques used in the analysis of anabolic agents. Finally, the classroom was led to critically evaluate and interpret the results as well as to question the adequacy of experimental methods used in forensic analysis to stimulate their critical thinking.

High surface area RuO2–TiO2 composite aerogels with different RuO2 concentrations were prepared through a modified non-alkoxide sol-gel route, followed by CO2 supercritical drying and evaluated as electrodes for energy storage devices. The TiO2 aerogels were synthesized via an ethanolic solution of TiCl3 with RuO2 being incorporated with an acidic solution of RuCl3.xH2O in different concentrations to obtain composite aerogels with 10 and 15 wt% RuO2. The aerogels were heat treated in different temperatures and characterized to evaluate the effect of the RuO2 on their specific capacitance. A specific capacitance of 25 F/g was obtained from TiO2–RuO2 aerogels containing with 10 wt% RuO2. Aerogels annealed at 450 °C exhibited lower electrochemical capacitance than the as-synthesized ones. Despite the relatively low specific capacitance, TiO2–RuO2 aerogels exhibited a remarkably high specific surface area of 316 m2/g, which make them useful for several other applications.

Abstract Urease enzyme (UE) has been reported to be a potent virulence factor for Helicobacter pylori (HP) bacteria indicated to be responsible for various gastrointestinal diseases. Therefore, the spread of HP, currently regarded by the World Health Organization as a class 1 carcinogen, could be better controlled by targeting UE. It is in this line that we have synthesized three new derivatives (2–4) of the naturally occurring olean-12-en-3-one (1), which was previously isolated from the figs of Ficus vallis-choudae Delile (Moraceae). Among the synthesized compounds, 3 and 4 contain an indole moiety. Their structures were unambiguously assigned by spectroscopic and spectrometric techniques (1D-NMR, 2D-NMR and MS). The starting material and the synthesized compounds were screened for UE inhibition activity, and showed significant activities with IC50 values ranging from 14.5 to 24.6 μM, with compound (1) being the most potent as compared to the positive control thiourea (IC50 = 21.6 μM). Amongst the synthetic derivatives, compound 4 was the most potent (IC50 = 17.9 μM), while the others showed activities close to that of the control. In addition, molecular docking study of target compounds 2–4 was performed in an attempt to explore their binding mode for the design of more potent UE inhibitors. Graphical Abstract

The local botanical Imperata cylindrica in Cameroon was investigated for its antibacterial potency. The methanol extract afforded a total of seven compounds, including five hitherto unreported compounds comprising three flavonoids (1–3) and two C-15 isoprenoid analogues (4 and 5) together with known derivatives (6 and 7). The novelty of the flavonoids was related to the presence of both methyl and prenyl groups. The potential origin of the methyl in the flavonoids is discussed, as well as the chemophenetic significance of our findings. Isolation was performed over repeated silica gel and Sephadex LH-20 column chromatography and the structures were elucidated by (NMR and MS). The crude methanol extract and isolated compounds showed considerable antibacterial potency against a panel of multi-drug resistant (MDR) bacterial strains. The best MIC values were obtained with compound (2) against S. aureus ATCC 25923 (32 µg/mL) and MRSA1 (16 µg/mL).

Inkjet printing presents a high potential for cost reduction of electronic devices manufacturing due to the capacity to deposit materials with high precision, less material waste, and large-scale production through the roll-to-roll printing processes. In this work, a nanostructured TiO2 ink was developed using TiO2 aerogel and an alkaline aqueous solution, which resulted in a very stable suspension. A high-intensity ultrasonic mixer was used to fragment and disperse TiO2 aerogels producing suspensions with particles smaller than 200 nm, which are suitable for the inkjet printing process. For the development of the ink, the viscosity and surface tension were adjusted by using glycerol and a surfactant (Triton X-100). The influence of those components on the properties of the ink was evaluated for different concentrations. After formulation of the inks, the printing parameters were adjusted to optimize the process. Films with high surface area and less than 100 nm grain size were successfully produced. Electrical measurements revealed a resistive-like behavior with the sheet resistance increasing with number of printed layers.

In this work, we present the design, laboratory tests, and the field trial results of a power-over-fiber (PoF) low power instrument transformer (LPIT) for voltage and current measurements in the medium voltage distribution networks. The new proposed design of this power-over-fiber LPIT aims to overcome the drawbacks presented by the previous technologies, such as the continuous operation (measuring and data transmission) for a wide current range conducted in the medium voltage transmission lines, damage due to lightning strikes, accuracy dependency on vibration, position and temperatures. The LPIT attends the accuracy criteria of IEC 61869-10 and IEC 61869-11 in terms of current and voltage accuracy and it attends the practical criteria adopted by Utilities companies including voltage measurements without removing the coating of the covered conductors. The PoF based LPIT was developed to be applied at 11.9 kV, 13.8 kV, and 23.0 kV phase-to-phase nominal voltages, and in two current ranges 1.25–30 A and 37.5–900 A. The digital data transmission of current, voltage, and temperature from the sensing unit to the processing unit uses a special synchronism technique and it is performed by two 62.5 µm multimode fibers in 850 nm. The optical powering in 976 nm is also performed by one 62.5 µm multimode fiber from the processing unit to the sensor unit. We presented all details of the sensor design and its laboratory characterization in terms of accuracy and temperature correction. We also presented the results of field tests of the sensor made in two different conditions: in a standard distribution network and an experimental hybrid fiber/power distribution network. We believe that these studies aim to incorporate optical fiber and devices, digital technologies, communications systems in electrical systems driving their evolution.

The MeOH/CH2Cl2 (1:1) extracts of the roots and leaves of Beilschmiedia louisii and B. obscura showed potent antitrypanosomal activity during preliminary screening on Trypanosoma brucei brucei. Phytochemical investigation of these extracts led to the isolation of a mixture of two new endiandric acid derivatives beilschmiedol B (1) and beilschmiedol C (2), and one new phenylalkene obscurene A (3) together with twelve known compounds (4–15). In addition, four new derivatives (11a–11d) were synthesized from compound 11. Their structures were elucidated based on their NMR and MS data. Compounds 5, 6, and 7 were isolated for the first time from the Beilschmiedia genus. Additionally, the NMR data of compound 4 are given here for the first time. The isolates were evaluated for their antitrypanosomal and antimalarial activities against Tb brucei and the Plasmodium falciparum chloroquine-resistant strain Pf3D7 in vitro, respectively. From the tested compounds, the mixture of new compounds 1 and 2 exhibited the most potent antitrypanosomal activity in vitro with IC50 value of 4.91 μM.

Background: broilers spend most of their lives in contact with litter; litter quality can affect their health and performance. Objective: the effects of litter treatment on performance and carcass lesions were evaluated in five consecutive flocks with 640 male broilers each. Methods: a completely randomized model was used comprising eight treatments and four replicates. The treatments included (1) untreated litter, (2) litter subjected to in-house composting, (3) litter treated (LT) with aluminum sulfate, (4) LT with gypsum, (5) LT with quicklime, (6) LT with dolomitic limestone, (7) LT with zeolite, and (8) LT with charcoal. Chopped elephant-grass hay was used as poultry litter in all flocks. Results: none of the litter treatments were found to influence the performance and carcass lesions of the male broilers in all five flocks. Furthermore, poultry litter treatments were not economically viable. Conclusion: poultry litter treatments did not affect the performance and scores of carcass lesions of male broilers, but increased the cost of poultry production.

Introducción y objetivos: La coartación aórtica es una de las enfermedades congénitas cardiovasculares más frecuentes, y su resolución quirúrgica se acompaña de un 11% de complicaciones a largo plazo, entre las cuales se encuentran los aneurismas y pseudoaneurismas. El objetivo del presente trabajo consiste en reportar la experiencia de nuestro centro en el manejo quirúrgico de los aneurismas de aorta descendente poscirugía de coartación aórtica. Métodos: Trabajo retrospectivo de 6 casos intervenidos desde enero de 2006 hasta abril de 2014, con antecedentes de corrección quirúrgica de coartación aórtica con parche en la infancia y diagnóstico de aneurisma de aorta descendente en el seguimiento. Resultados: De 6 pacientes, 4 eran varones y 2 mujeres; la edad promedio al momento de la primera cirugía fue de 8,2 ± 2,9 años, y la de la corrección del aneurisma de aorta descendente fue de 34,3 ± 5,1 años; el tiempo transcurrido desde la primera cirugía a la reintervención fue de 26 ± 5 años. Se realizó el reemplazo de la aorta descendente con prótesis de PTRC y se emplearon 2 estrategias de perfusión: en 5 pacientes se utilizó circulación extracorpórea y en uno se llevó a cabo derivación auriculofemoral con centrífuga. Cuatro pacientes registraron complicaciones menores (hemotórax, neumotórax, quilotórax, síndrome de Horner, disfonía y cefalea), y un paciente falleció. Los pacientes se encontraron asintomáticos durante un seguimiento promedio de 44,8 meses. Conclusiones: En pacientes jóvenes y con escasas comorbilidades, la cirugía ofrece una resolución definitiva para los aneurismas poscirugía de coartación aórtica, presentando una morbimortalidad aceptable

This work reports the one-step synthesis of bacterial nanocellulose (BNC) incorporated with polypyrrole (PPy) by chemical in situ polymerization of pyrrole (Py) using CuCl2·2H2O as both oxidant agent and functional component, varying the concentration and molar ratio. Electrical, morphological, and physical-chemical properties of these nanocomposites were investigated. The results revealed that with the increase of Py concentration and molar ratio, the nanocomposites presented traces of copper chloride and copper oxide as shown by Raman and XRD analysis. The quality of bacterial cellulose nanofibers coating by the polymer and the electrical conductivity of the nanocomposites was directly affected by those variables. The combination of the conducting polymer with the oxidant agent offers possibilities for different applications such as electronic devices and sensors.

There is continuing need for new and improved drugs to tackle malaria, which remains a major public health problem, especially in tropical and subtropical regions of the world. Natural products represent credible sources of new antiplasmodial agents for antimalarial drug development. Endophytes that widely colonize healthy tissues of plants have been shown to synthesize a great variety of secondary metabolites that might possess antiplasmodial benefits. The present study was carried out to evaluate the antiplasmodial potential of extracts from endophytic fungi isolated from Symphonia globulifera against a chloroquine-resistant strain of Plasmodium falciparum (PfINDO). Sixty-one fungal isolates with infection frequency of 67.77% were obtained from the bark of S. globulifera. Twelve selected isolates were classified into six different genera including Fusarium, Paecilomyces, Penicillium, Aspergillus, Mucor, and Bipolaris. Extracts from the 12 isolates were tested against PfINDO, and nine showed good activity (IC50 < 10 μg·mL−1) with three fungi including Paecilomyces lilacinus (IC50 = 0.44 μg·mL−1), Penicillium janthinellum (IC50 = 0.2 μg·mL−1), and Paecilomyces sp. (IC50 = 0.55 μg·mL−1) showing the highest promise. These three isolates were found to be less cytotoxic against the HEK293T cell line with selectivity indices ranging from 24.52 to 70.56. Results from this study indicate that endophytic fungi from Symphonia globulifera are promising sources of hit compounds that might be further investigated as novel drugs against malaria. The chemical investigation of active extracts is ongoing.

The crystal structure of the title compound, C32H39NO4, confirms the absolute configuration of the seven chiral centres in the molecule. The molecule has a 1,1-dimethylprop-2-enyl substituent on the indole nucleus and this nucleus shares one edge with the five-membered ring which is, in turn, connected to a sequence of three edge-shared fused rings. The skeleton is completed by the 7,7-trimethyl-6,8-dioxabicyclo[3.2.1]oct-3-en-2-one group connected to the terminal cyclohexene ring. The two cyclohexane rings adopt chair and half-chair conformations, while in the dioxabicyclo[3.2.1]oct-3-en-2-one unit, the six-membered ring has a half-chair conformation. The indole system of the molecule exhibits a tilt of 2.02 (1)° between its two rings. In the crystal, O—H...O hydrogen bonds connect molecules into chains along [010]. Weak N—H...π interactions connect these chains, forming sheets parallel to (10-1).

The title compound, C24H31NO3 {systematic name: (E)-3-[(1R*,2S*,4aS*,8aR*)-2-(benzo[d][1,3]dioxol-5-yl)-1,2,4a,5,6,7,8,8a-octahydronaphthalen-1-yl]-N-isobutylacrylamide}, is a natural product isolated from the stem bark of B. obscura. It is composed of an octahydronaphthalene ring system substituted with an essentially planar benzodioxole ring system [r.m.s. deviation = 0.012 Å] and an extended isobutylacrylamide group. In the crystal, molecules are linked by N—H...O hydrogen bonds, forming chains propagating along [100]. The chains are linked by pairs of C—H...O hydrogen bonds, involving inversion-related benzodioxole ring systems, forming ribbons lying parallel to (010). There are also C—H...π interactions present within the ribbons.

A new prenylated pyranoxanthone, symphonin (1), 2-(3,3-dimethylallyl)-1,5- dihydroxy-6,7-dimethoxy-2”,2”-dimethylpyrano (5”,6”:3,4) xanthone, the known compounds guttiferone A, oleanolic acid and sitosterol were isolated from the methanol extract of the seeds of Symphonia globulifera (Guttiferae). The structural elucidation of the new compound was based mainly on spectroscopic analyses. The new xanthone showed antimicrobial activity against Staphylococcus aureus, Streptococcus feacalis, Klebsiella pneumonia and Escherichia coli.

In the last decades, there has been an increase of cholera epidemics caused by multidrug resistant strains. Particularly, the integrative and conjugative element (ICE) seems to play a major role in the emergence of multidrug resistant Vibrio cholerae. This study fully characterized, by whole genome sequencing, new ICEs carried by multidrug resistant V. cholerae O1 strains from Nigeria (2010) (ICEVchNig1) and Nepal (1994) (ICEVchNep1). The gene content and gene order of these two ICEs are the same, and identical to ICEVchInd5, ICEVchBan5 and ICEVchHai1 previously identified in multidrug resistant V. cholerae O1. This ICE is characterized by dfrA1, sul2, strAB and floR antimicrobial resistance genes, and by unique gene content in HS4 and HS5 ICE regions. Screening for ICEs, in publicly available V. cholerae genomes, revealed the occurrence and widespread distribution of this ICE among V. cholerae O1. Metagenomic analysis found segments of this ICE in marine environments far from the direct influence of the cholera epidemic. Therefore, this study revealed the epidemiology of a spatio-temporal prevalent ICE in V. cholerae O1. Its occurrence and dispersion in V. cholerae O1 strains from different continents throughout more than two decades can be indicative of its role in the fitness of the current pandemic lineage.

We study how the synaptic connections in a pair of excitable electronic neurons affect the coherence of their spike trains when the neurons are submitted to noise from independent sources. The coupling is provided by electronic circuits which mimic the dynamics of chemical AMPA synapses. In particular, we show that increasing the strength of an unidirectional synapse leads to a decrease of coherence in the post-synaptic neuron. More interestingly, we show that the decrease of coherence can be reverted if we add a synapse of sufficient strength in the reverse direction. Synaptic symmetry plays an important role in this process and, under the right choice of parameters, increases the network coherence beyond the value achieved at the resonance due to noise alone in uncoupled neurons. We also show that synapses with a longer time scale sharpen the dependency of the coherence on the synaptic symmetry. The results were reproduced by numerical simulations of a pair of synaptically coupled FitzHugh-Nagumo models.