Graphene Materials to Remove Organic Pollutants and Heavy Metals from Water: Photocatalysis and Adsorption

Since graphene was isolated from graphite, different researches have been developed around it. The versatility of graphene properties and their derivates, such as graphene oxide or doped and functionalized graphene materials have expanded the possible applications of these nanostructures. The areas studied of graphene include the following: nanocomposites, drug delivery, transistors, quantum dots, optoelectronic, storage energy, sensors, catalyst support, supercapacitors, among others. However, other important field of these materials is their applications in environment, mainly in the removal of pollutants in water. In this context, there are two possible alternatives to use graphene materials in water purification: photocatalysis and adsorption. In the first case, the key is related to the bandgap and semiconductors properties of these materials, also the versatility of different graphene structures after the oxidation or functionalization, play an important role to get different arrangements useful in photocatalysis and avoid recombination, one of the problems of typical semiconductors photocatalysts. In the second case, surface area and useful chemical groups in carbon material give different options to produce efficient adsorbents depending on different synthesis conditions. Thus, this book chapter covers a review of the photocatalytic activity of graphene materials with emphasis in the removal of organic pollutants and heavy metals from water, in the next topics: graphene-based semiconductor photocatalyst and graphene oxide as photocatalyst. On the other hand, the chapter also discusses the research related to the removal of organic compounds and heavy metals using graphene materials as adsorbents, the topics in this second part are as follows: graphene and graphene oxide as adsorbent of heavy metals from water, graphene, and graphene oxide as adsorbent of organic pollutants from water, functionalized graphene materials as adsorbent of water pollutants, carbon nanomaterials vs. graphene as adsorbents. Therefore, the book chapter presents a review and the discussion of the keys that play an important role in the advances in the research of graphene materials as photocatalysts. In addition, the isotherms and kinetic that produce these materials as adsorbents are also reviewed and discussed, because adsorption process in these materials is important to remove pollutants from water, but also for adsorption is a first step to achieve photocatalyst. The future of this topic in graphene materials is also analyzed

Response of obesity-resistant BALB/c mice to a ketogenic diet

Introduction. The ketogenic diet (KD) is a high-fat, low-carbohydrate diet in which the body undergoes metabolic adjustments that stimulate ketogenesis, thereby increasing circulating ketone bodies. Loss of body weight is attributed to these adjustments, as well as neuroprotective properties. However, the mechanisms involved are still not fully elucidated. That aim of this work was to evaluate the effect of a ketogenic diet on body composition, feeding behavior and glucose metabolism in mice of the BALB/c strain, a mouse model resistant to obesity. Materials and methods. BALB/c mice of both sexes, 12 weeks old, were divided into KD and control groups, which received a ketogenic diet (Research Diets) or standard chow (LabDiet 5001), respectively, for 23 days. Throughout the experiment, body weight gain, water and food intake were measured, whereas body mass index (BMI), the percentage of interscapular, inguinal, and visceral adipose tissue and blood b-hidroxybutyrate levels were measured at the end of the protocol. In addition, glucose tolerance tests were carried out at the beginning and at the end of the experiment. Results. Similar body weight gain (10%) was observed in males and females on KD compared to the control group (p\u3c0.05). However, a higher BMI was observed only in males. The KD group consumed 50% less food in both sexes, whereas water consumption was diminished 25% in males and 50% in females, compared to the control (p= 0.0001). The estimated energy intake was lower (12 Kcal) in males on ketogenic diet, but not in females. Regarding the metabolic state at day 23, in KD mice levels of b-hidroxybutyrate increased to 0.4 mmol/L in males and 0.7 mmol/L in females. Mice of both sexes on KD showed increased inguinal and visceral fat, when compared to the control group on standard chow. At day 23, the glucose tolerance test showed an increase in the area under the curve, indicating impaired glucose tolerance, in both males and females on KD. Conclusions. In obesity-resistant BALB/c mice, the consumption of a ketogenic diet for a short period induces a state of nutritional ketosis accompanied by weight gain, increased fat tissue, and impaired glucose intolerance

Relationship between alcoholism addiction and periodontitis. An in vivo study using drinking-in-darkness protocol in rats.

Periodontal disease (PD) has been considered a probable risk factor for several systemic diseases. Among them, PD is presumed to be one of the possible etiologies of chronic illness of the central nervous system. In this context, poor oral health and PD is associated with substance abuse in humans. However, if periodontal lesions can produce addiction is unknown. This paper aims to evaluate the possibility that chronic periodontal injury (CPL) can cause ethanol binge intake in drink-in-darkness (DID) protocol in rats. In CPL group (n=10) experimental damage was done to the periodontal tissue of the second maxillary molar, the control group (n=9) received sham injury. Forty-three days after CPL the intake of ethanol was assessed using several concentrations in DID experiment. During the DID experiment, we observed significant differences between the binge-type consumption of ethanol at the lowest concentration of 10% (p=0.01). Differences in consumption of 20% ethanol are observed during a few days (p=0.04), and there are no differences in consumption at 40% concentration of ethanol (p=0.2). It is concluded that chronic periodontal lesion leads to alcoholism in Wistar rats

Improved Performance of an Epoxy Matrix as a Result of Combining Graphene Oxide and Reduced Graphene

We present an easy and effective way to improve the mechanical properties of an epoxy matrix by reinforcing it with a combination of graphene oxide (GO) and reduced graphene oxide (RGO). These nanocomposites were prepared with different load of nanofillers: 0.1, 0.4, 0.7, 1.0 wt% and a neat epoxy. Ratios of graphene oxide and reduced graphene (GO : RGO) employed were: 0 : 1, 0.25 : 0.75, 0.5 : 0.5, 0.75 : 0.25, and 1 : 0. Results show that with only 0.4 wt% and a ratio 0.2 : 0.75 of GO : RGO, tensile strength and tensile toughness are 52% and 152% higher than neat epoxy while modulus of elasticity was improved ~20%. The obtained results suggest that it is possible achieve advantageous properties by combining graphene in oxidized and reduced conditions as it shows a synergic effect by the presence of both nanofillers

Sex pheromones are not always attractive: changes induced by learning and illness in mice

A male-specific major urinary protein named darcin is attractive to female mice, Mus musculus, stimulates a learned attraction to volatile components of a male's urinary odour and induces spatial learning. In this article we show that darcin also induces learned attraction for a previously neutral olfactory stimulus (the odorant isoamyl acetate), acquired by repeated presentation of both stimuli together. We hypothesize that this is a case of olfactory–vomeronasal associative learning, in which darcin acts as the unconditioned reinforcer. However, the presence of darcin is not always attractive to adult female mice. Urine from males parasitized by the nematode Aspiculuris tetraptera has no attractive value for females, despite apparently normal presence of darcin. The loss of attractive value may be due to unknown infection-derived chemicals whose detection overrides the attraction induced by darcin, or prevents detection of darcin by other (unknown) mechanisms. Other cases in which male urine (and thus the presence of darcin) does not induce attraction are discussed, namely in lactating females, which respond with aggression towards intruder males, and in prepubertal females, which show aversive responses towards unfamiliar male urine. Thus, although the darcin sex pheromone induces attraction in adult female mice that does not need to be learned, such innate pheromonal responses can be modulated by the physiological or health status of the sender and receiver. This provides a degree of flexibility in response to pheromonal signals, but such that individuals of the same class or status still share consistent predictable responses to improve their reproductive fitness. Further, by readily inducing the same response towards other odorants through associative learning, pheromones can also target responses flexibly towards odour signatures at an individual-specific level

Analysis of qPCR reference genes stability determination methods and a practical approach for efficiency calculation on a turbot (Scphthalmus maximus) gonad dataset

Gene expression analysis by reverse transcription quantitative PCR (qPCR) is the most widely used method for analyzing the expression of a moderate number of genes and also for the validation of microarray results. Several issues are crucial for a successful qPCR study, particularly the selection of internal reference genes for normalization and efficiency determination. There is no agreement on which method is the best to detect the most stable genes neither on how to perform efficiency determination. In this study we offer a comprehensive evaluation of the characteristics of reference gene selection methods and how to decide which one is more reliable when they show discordant outcomes. Also, we analyze the current efficiency calculation controversy. Our dataset is composed by gonad samples of turbot at different development times reared at different temperatures. Turbot (Scophthalmus maximus) is a relevant marine aquaculture European species with increasing production in the incoming years. Since females largely outgrow males, identification of genes related to sex determination, gonad development and reproductive behavior, and analysis of their expression profiles are of primary importance for turbot industryVersión del edito

Application of Vegetation Indices to Estimate Acorn Production at Iberian

The Iberian pig valued natural resources of the pasture when fattened in mountain. The variability of acorn production is not contained in any line of Spanish agricultural insurance. However, the production of arable pasture is covered by line insurance number 133 for loss of pasture compensation. This scenario is only contemplated for breeding cows and brave bulls, sheep, goats and horses, although pigs are not included. This insurance is established by monitoring ten-day composites Normalized Difference Vegetation Index (NDVI) measured by satellite over treeless pastures, using MODIS TERRA satellite. The aim of this work is to check if we can use a satellite vegetation index to estimate the production of acorns

An oleuropein β-glucosidase from olive fruit is involved in determining the phenolic composition of virgin olive oil

Phenolic composition of virgin olive oil is determined by the enzymatic and/or chemical reactions that take place during olive fruit processing. Of these enzymes, β-glucosidase activity plays a relevant role in the transformation of the phenolic glycosides present in the olive fruit, generating different secoiridoid derivatives. The main goal of the present study was to characterize olive fruit β-glucosidase genes and enzymes responsible for the phenolic composition of virgin olive oil. To achieve that, we have isolated an olive β-glucosidase gene from cultivar Picual (OepGLU), expressed in Nicotiana benthamiana leaves and purified its corresponding recombinant enzyme. Western blot analysis showed that recombinant OepGLU protein is detected by an antibody raised against the purified native olive mesocarp β-glucosidase enzyme, and exhibits a deduced molecular mass of 65.0 kDa. The recombinant OepGLU enzyme showed activity on the major olive phenolic glycosides, with the highest levels with respect to oleuropein, followed by ligstroside and demethyloleuropein. In addition, expression analysis showed that olive GLU transcript level in olive fruit is spatially and temporally regulated in a cultivar-dependent manner. Furthermore, temperature, light and water regime regulate olive GLU gene expression in olive fruit mesocarp. All these data are consistent with the involvement of OepGLU enzyme in the formation of the major phenolic compounds present in virgin olive oil

Cardiotrophin-1 opposes renal fibrosis in mice: Potential prevention of chronic kidney disease

[EN]Chronic kidney disease is characterized by tubulointerstitial fibrosis involving inflammation, tubular apoptosis, fibroblast proliferation and extracellular matrix accumulation. Cardiotrophin-1, a member of the interleukin-6 family of cytokines, protects several organs from damage by promoting survival and anti-inflammatory effects. However, whether cardiotrophin-1 participates in the response to chronic kidney injury leading to renal fibrosis is unknown. We hypothesized and assessed the potential role of cardiotrophin-1 in a mice model of tubulointerstitial fibrosis induced by unilateral ureteral obstruction (UUO). Three days after UUO, obstructed kidneys from cardiotrophin-1-/- mice show higher expression of inflammatory markers IL-1β, Cd68, ICAM-1, COX-2 and iNOs, higher activation of NF-κB, higher amount of myofibroblasts and higher severity of tubular damage and apoptosis, compared with obstructed kidneys from wild-type littermates. In a later stage, obstructed kidneys from cardiotrophin-1-/- mice show higher fibrosis than obstructed kidneys from wild-type mice. Interestingly, administration of exogenous cardiotrophin-1 prevents the increased fibrosis resulting from the genetic knockout of cardiotrophin-1 upon UUO, and supplementation of wild-type mice with exogenous cardiotrophin-1 further reduces the renal fibrosis induced by UUO. In vitro, renal myofibroblasts from cardiotrophin-1-/- mice have higher collagen I and fibronectin expression and higher NF-κB activation than wild-type cells. Cardiotrophin-1 participates in the endogenous response that opposes renal damage by counteracting the inflammatory, apoptotic and fibrotic processes. And exogenous cardiotrophin-1 is proposed as a candidate for the treatment and prevention of chronic renal fibrosis