Double layer charging driven carbon dioxide adsorption limits the rate of electrochemical carbon dioxide reduction on Gold.

Electrochemical CO[Formula: see text] reduction is a potential route to the sustainable production of valuable fuels and chemicals. Here, we perform CO[Formula: see text] reduction experiments on Gold at neutral to acidic pH values to elucidate the long-standing controversy surrounding the rate-limiting step. We find the CO production rate to be invariant with pH on a Standard Hydrogen Electrode scale and conclude that it is limited by the CO[Formula: see text] adsorption step. We present a new multi-scale modeling scheme that integrates ab initio reaction kinetics with mass transport simulations, explicitly considering the charged electric double layer. The model reproduces the experimental CO polarization curve and reveals the rate-limiting step to be *COOH to *CO at low overpotentials, CO[Formula: see text] adsorption at intermediate ones, and CO[Formula: see text] mass transport at high overpotentials. Finally, we show the Tafel slope to arise from the electrostatic interaction between the dipole of *CO[Formula: see text] and the interfacial field. This work highlights the importance of surface charging for electrochemical kinetics and mass transport

Cavitating Langmuir Turbulence in the Terrestrial Aurora

Langmuir cavitons have been artificially produced in the earth's ionosphere, but evidence of naturally-occurring cavitation has been elusive. By measuring and modeling the spectra of electrostatic plasma modes, we show that natural cavitating, or strong, Langmuir turbulence does occur in the ionosphere, via a process in which a beam of auroral electrons drives Langmuir waves, which in turn produce cascading Langmuir and ion-acoustic excitations and cavitating Langmuir turbulence. The data presented here are the first direct evidence of cavitating Langmuir turbulence occurring naturally in any space or astrophysical plasma.Comment: 4 pages, 4 figures, published in PRL on 9 March 2012 http://link.aps.org/doi/10.1103/PhysRevLett.108.10500

Deep learning for inferring cause of data anomalies

Daily operation of a large-scale experiment is a resource consuming task, particularly from perspectives of routine data quality monitoring. Typically, data comes from different sub-detectors and the global quality of data depends on the combinatorial performance of each of them. In this paper, the problem of identifying channels in which anomalies occurred is considered. We introduce a generic deep learning model and prove that, under reasonable assumptions, the model learns to identify 'channels' which are affected by an anomaly. Such model could be used for data quality manager cross-check and assistance and identifying good channels in anomalous data samples. The main novelty of the method is that the model does not require ground truth labels for each channel, only global flag is used. This effectively distinguishes the model from classical classification methods. Being applied to CMS data collected in the year 2010, this approach proves its ability to decompose anomaly by separate channels.Comment: Presented at ACAT 2017 conference, Seattle, US

Unbalancing Zur (FurB)-mediated homeostasis in Anabaena sp. PCC7120: Consequences on metal trafficking, heterocyst development and biofilm formation

Zinc is required for the activity of many enzymes and plays an essential role in gene regulation and redox homeostasis. In Anabaena (Nostoc) sp. PCC7120, the genes involved in zinc uptake and transport are controlled by the metalloregulator Zur (FurB). Comparative transcriptomics of a zur mutant (Δzur) with the parent strain unveiled unexpected links between zinc homeostasis and other metabolic pathways. A notable increase in the transcription of numerous desiccation tolerance-related genes, including genes involved in the synthesis of trehalose and the transference of saccharide moieties, among many others, was detected. Biofilm formation analysis under static conditions revealed a reduced capacity of Δzur filaments to form biofilms compared to the parent strain, and such capacity was enhanced when Zur was overexpressed. Furthermore, microscopy analysis revealed that zur expression is required for the correct formation of the envelope polysaccharide layer in the heterocyst, as Δzur cells showed reduced staining with alcian blue compared to Anabaena sp. PCC7120. We suggest that Zur is an important regulator of the enzymes involved in the synthesis and transport of the envelope polysaccharide layer, influencing heterocyst development and biofilm formation, both relevant processes for cell division and interaction with substrates in its ecological niche

Antiseptics and disinfectants for the treatment of vaginal discharge in non-pregnant women (Protocol)

Q1Q1Paciente femeninoThis is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the safety and effectiveness of antiseptics and disinfectants for the treatment of vaginal discharge in non‐pregnant women. Description of the condition A normal and healthy vaginal ecosystem is defined by an acidic environment (pH less than 4.5), which is inhospitable for most bacteria and viruses. This acidic environment is associated with the presence of lactobacilli and hydrogen peroxide (H2O2); a decrease of these buffer agents is linked with vaginal infections (Verstraelen 2009). Vaginal discharge syndrome represents a group of vaginal infections that are characterized by abnormal vaginal secretion, irritation, vulvar itching and sometimes vaginal odour (CDC 2017). In most cases, it is diagnosed by clinical signs (Gaitán‐Duarte 2013). The most common vaginal infections with vaginal discharge as the main clinical symptom are: bacterial vaginosis (BV), vulvovaginal candidiasis (VC), and trichomoniasis (TV), which is a sexually transmitted infection (Gaitán‐Duarte 2013; Sherrard 2011). Prevalence varies from 40% for BV, to 12% for VC and less than 1% for trichomoniasis (Angel 2012). Bacterial vaginosis is an infection characterized by a change in the vaginal flora due to the decrease of lactobacilli, an increase in vaginal pH and anaerobic bacteria such as Gardnerella vaginalis, genital mycoplasma, anaerobic Gram‐negative rods, Gram‐positive cocci (Beigi 2004; Petersen 2002; Verstraelen 2012). Symptomatic patients are evidenced by foul‐smelling, profuse vaginal discharge (which is thin, white and homogenous, and coats the walls of the vagina and vestibule) and no signs of vulvar or vaginal inflammation (Verstraelen 2009). BV is not a sexual infection, though it is associated with sexual intercourse (Amaya‐Guio 2016). It can remit spontaneously or it can be persistent or recurrent, especially when the woman engages in vaginal douching or frequent sexual activity (which can cause changes in vaginal pH and lead to the decrease or lack of lactobacilli), or when lactobacilli are attacked by specific viruses and are subsequently unable to recolonize the vagina due to the overgrowth of anaerobic bacteria (Sherrard 2011). Bacterial vaginosis is a significant genital tract infection; published studies have found it to be associated with pelvic inflammatory disease, intrauterine infections, post‐procedural gynaecological infections, and predisposition to an increased risk of sexually transmitted diseases, such as trichomoniasis, gonorrhea, chlamydia and the human immunodeficiency virus (HIV) (Verstraelen 2009). Vulvovaginal candidiasis is caused by an overgrowth of Candida albicans (90%), C. glabrata,C. tropicalis, and other species (Sherrard 2011). This infection has inflammatory symptoms such as edema, erythema, vulvar excoriation, fissure formation, pruritus, superficial dyspareunia, dysuria, irritation, curdy vaginal discharge and soreness (Molteni 2004). Trichomoniasis is the most common non‐viral sexually transmitted infection, caused by an anaerobic protozoan called Trichomonas vaginalis (humans are the only known hosts). The symptoms include dysuria, itching, vulvar irritation, "strawberry" cervix visible to naked eye (2%), and occasionally, abdominal pain and greenish‐yellow, foamy, foul‐smelling vaginal discharge (KIissinger 2015; Jeffery 2017). The diagnosis of VB as the other two infections (VC and TV) in the vaginal discharge syndrome is by manly clinical symptoms. Treatment for vaginal discharge syndrome mainly includes antimicrobials, such as imidazoles (metronidazole or tinidazole) for VB and TV, or used as antifungal agents (clotrimazole or fluconazole) and lincosamines (clindamycin) for VB.Revista Nacional - Indexad

FurC (PerR) from Anabaena sp. PCC7120: a versatile transcriptional regulator engaged in the regulatory network of heterocyst development and nitrogen fixation

FurC (PerR) from Anabaena sp. PCC7120 was previously described as a key transcriptional regulator involved in setting off the oxidative stress response. In the last years, the cross-talk between oxidative stress, iron homeostasis and nitrogen metabolism is becoming more and more evident. In this work, the transcriptome of a furC-overexpressing strain was compared with that of a wild-type strain under both standard and nitrogen-deficiency conditions. The results showed that the overexpression of furC deregulates genes involved in several categories standing out photosynthesis, iron transport and nitrogen metabolism. The novel FurC-direct targets included some regulatory elements that control heterocyst development (hetZ and asr1734), genes directly involved in the heterocyst envelope formation (devBCA and hepC) and genes which participate in the nitrogen fixation process (nifHDK and nifH2, rbrA rubrerythrin and xisHI excisionase). Likewise, furC overexpression notably impacts the mRNA levels of patA encoding a key protein in the heterocyst pattern formation. The relevance of FurC in these processes is bringing out by the fact that the overexpression of furC impairs heterocyst development and cell growth under nitrogen step-down conditions. In summary, this work reveals a new player in the complex regulatory network of heterocyst formation and nitrogen fixation

Illuminating the threat: a decade-long analysis of light pollution in major Colombian urban centres using satellite imagery

La contaminación lumínica es una forma de degradación ambiental que aumenta cada vez más en todo el mundo y afecta el entorno natural, la flora, la fauna y varios aspectos de la vida humana. A pesar de la creciente preocupación por esta problemática, en Colombia su estudio es aún muy limitado. Aquí analizamos de forma exhaustiva la expansión de la luz nocturna artificial en las principales ciudades de Colombia entre el 2012 y el 2022. Se evidenció así un aumento en los niveles de contaminación lumínica en las áreas urbanas de Bogotá, Barranquilla y Cartagena, en tanto que en las de Medellín, Cali y Bucaramanga disminuyó la radiancia promedio. Sin embargo, en todas las ciudades consideradas en el estudio la cobertura de áreas iluminadas aumentó, con un evidente incremento espacial del fenómeno. En el caso de Bogotá, se analizó detalladamente el fenómeno a nivel de localidades y, a partir de datos externos, se verificaron, además, las relaciones del aumento de la contaminación lumínica con la instalación de nuevas luminarias, el cambio a tecnologías LED, y el crecimiento de la densidad poblacional y el producto interno bruto de la ciudad.Light pollution is a form of environmental degradation present throughout the world that affects the natural environment, flora, fauna, and various aspects of human life. Despite the growing concern about this problem, its study in Colombia is still minimal. Here we present a comprehensive analysis of the expansion of artificial nighttime lighting in the main Colombian cities between 2012 and 2022. According to the analysis, light pollution levels in the urban areas of Bogotá, Barranquilla, and Cartagena increased, while in Medellín, Cali, and Bucaramanga, they decreased. However, all the cities evaluated experienced an expansion in the coverage of illuminated areas revealing an evident spatial increase of the problem. In the case of Bogotá, the phenomenon was studied at the locality level. Additionally, we used external data to analyze the relationship between increased light pollution and the installation of new luminaires, the change to LED technologies, and the growing population density and gross domestic product (GDP) in the city. Our results provide valuable information on the threat of light pollution in Colombia and the need to take measures to help control the associated environmental degradation

2-oxoglutarate modulates the affinity of FurA for the ntcA promoter in Anabaena sp. PCC 7120

2-oxoglutarate (2-OG) is a central metabolite that acts as a signaling molecule informing about the status of the carbon/nitrogen balance of the cell. In recent years, some transcriptional regulators and even two-component systems have been described as 2-OG sensors. In the nitrogen-fixing cyanobacterium Anabaena sp. PCC 7120, two master regulators, NtcA and FurA, are deeply involved in the regulation of nitrogen metabolism. Both of them show a complex intertwined regulatory circuit to achieve a suitable regulation of nitrogen fixation. In this work, 2-OG is found to bind FurA, modulating the specific binding of FurA to the ntcA promoter. This study provides evidence of a new additional control point in the complex network controlled by the NtcA and FurA proteins