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The cost-effective implementation of nanofibrillated cellulose (CNF) at industrial scale requires optimizing the quality of the nanofibers according to their final application. Therefore, a portfolio of CNFs with different qualities is necessary, as well as further knowledge about how to obtain each of the main qualities. This paper presents the influence of various production techniques on the morphological characteristics and properties of CNFs produced from a mixture of recycled fibers. Five different pretreatments have been investigated: a mechanical pretreatment (PFI refining), two enzymatic hydrolysis strategies, and TEMPO-mediated oxidation under two different NaClO concentrations. For each pretreatment, five high-pressure homogenization (HPH) conditions have been considered. Our results show that the pretreatment determines the yield and the potential of HPH to enhance fibrillation and, therefore, the final CNF properties. These results enable one to select the most effective production method with the highest yield of produced CNFs from recovered paper for the desired CNF quality in diverse applications. [ABSTRACT FROM AUTHOR]

Vegetable trimmings can be used to stabilize edible O/W Pickering emulsions. The lignocellulosic biomass (LCB) from the leek trimmings was mechanically treated to produce high-yield lignocellulose micro and nanofibrils (LCF) using a high-pressure homogenizer (HPH). Different O/W phase ratios (20/80, 30/70, and 40/60 wt.%) were studied. The use of the micro/nano cellulosic fibers increased the stabilization of the Pickering emulsions by 30–40%. In all cases, stable emulsions were obtained, with emulsification indexes > 92%. The respective stabilization mechanism was thoroughly analysed from confocal laser scanning, and cryo-scanning electron microscopy, which showed the fibers are not coating the droplets but forming a network that traps the droplets and prevents coalescence. The most stable batch formulations, O/W 30/70 wt.% (LCB 4.2 wt.%) and O/W 40/60 wt.% (LCB 3.6 wt.%), were also studied in continuous mode using NETmix technology. Results show the scale-up feasibility of the production of Pickering emulsions containing LCF. Most significantly, this work proposes a continuous process to produce Pickering emulsions stabilized with a natural biopolymer extracted from leek trimmings, which is suitable to industrial manufacturing processes. This valorizes the vegetable trimmings that are usually tossed away as waste, creating new market niches and business models based on circular economy concepts. [ABSTRACT FROM AUTHOR]

Several studies have been carried out to obtain unsaturated fatty acid (UFA) concentrates, due to their nutritional importance in food applications. The aim of this work was to obtain UFA concentrates from bleached cobia (Rachycentron canadum) and Argentine croaker (Umbine canosai) oil by complexation with urea, and to evaluate their physicochemical and thermal properties during processing. The fatty acids found in high amounts in the crude and bleached oils of cobia and Argentine crocker were palmitic, oleic and linoleic acids. Higher percentages of UFA were present in the oils extracted from the visceras, around 69 and 63% for cobia and Argentine croaker, respectively, and after complexation with urea, the percentages of UFA present in both concentrates were around 88%. Through the thermograms it was possible to observe that the UFA concentrates showed a 50% decrease in their maximum degradation temperature. [ABSTRACT FROM AUTHOR]

In this paper a FE based lifetime assessment methodology for short glass fiber reinforced polybutylene terephthalate (PBT-GF30) under thermo-mechanical fatigue (TMF) loading is presented. In order to investigate the fatigue behavior of the material both isothermal strain controlled fatigue (ISCF) tests at four different temperatures and thermo-mechanical fatigue tests were conducted on plain and notched specimens. Through a comparative microscopic investigation of thermo-mechanical fatigue fracture surfaces and isothermal strain controlled fatigue fracture surfaces created at different temperatures the material state (i.e. the temperature) at which thermo-mechanical fatigue failure occurs was determined. On the basis of this insight a life estimation methodology derived from a strain energy density (SED) based approach was developed for the corresponding isothermal strain controlled fatigue load case [1]. Through consideration of additional effects occurring during thermo-mechanical fatigue testing (i.e. relaxation, spatial temperature gradients, creep damage due to low testing frequencies and plastic overloads) the isothermal approach was successfully adapted to the thermo-mechanical fatigue load case. [ABSTRACT FROM AUTHOR]

Highlights: [•] CuO/CeO2 is more selective in CO-PROX if CeO2 support has cube-shaped nanoparticles. [•] Nanocube-based CuO/CeO2 retains Cu+ carbonyls to higher T under CO-PROX reaction. [•] Effect is due to stabilization of Cu against reduction to Cu0. [•] XRD and EPR indicate different CuO growth mode on CeO2 nanocubes. [•] DFT evidences stronger interaction of CuO on (001) than on (111) CeO2 surface. [Copyright &y& Elsevier]

RAS clustering at the cell membrane is critical to activate signaling in cells, but whether this clustering is mediated exclusively by its c-terminal hypervariable region, receives contributions from the G-domain of RAS, and/or is influenced by secondary effectors has been intensely debated. Reports that G-domain mutations do not modulate RAS-RAS interactions have led some to question the validity of previous experiments that indicate the G-domain plays a role in RAS clustering/interactions. Here we reconcile these findings by clarifying the impact of experimental variables, such as protein expression levels, cellular context, RAS zygosity, and secondary effector interactions on RAS clustering. Lack of control over these variables impacts the results using Gdomain mutations across various assay systems and can lead to unsound conclusions. [ABSTRACT FROM AUTHOR]

Conventional methods used for the quantification of adherent material contained in a pulp suspension propose either filtration of the sample, which may lead to loss of sticky material in the filtrate, or dilution of the pulp, which may cause destabilization of the dissolved and colloidal material; thus, leading to unreliable results. In 1998, the Cellulose and Paper Group of University Complutense of Madrid developed a deposition tester which aimed to quantify the adherence of material (microstickies and secondary stickies from dissolved and colloidal material) that was present in white waters generated during papermaking processes. In this paper, an improved deposition tester capable of directly studying the deposition tendency of total stickies in pulps without dilution is described and validated. The design of this device prevents the rotor system from being clogged and blocked by pulps, hence, being able to quantify deposits without having to apply any filtration and/or dilution stages. In addition, the study provides determination of the equipment optimum operating conditions as well as comparison between the improved deposition tester and the one previously developed. Results show that this deposition tester can determine the adherent material contained in pulps with a consistency up to 1%. The comparison of results obtained after applying both deposition quantification methods shows that the quantities of deposits that were measured with the improved tester are slightly lower than those obtained with the application of the conventional method; however, they are in the same order of magnitude. Therefore, it is possible for the improved tester to determine total stickies in all cases, including cases that it is not convenient to apply a filtration and/or a dilution stage. [ABSTRACT FROM AUTHOR]

The use of enzymes has been suggested as an environmentally friendly alternative to complement conventional chemical deinking in the recycling of recovered paper. This study compares the use of cellulases/hemicellulases versus the laccase-mediator system for deinking printed fibers from newspapers and magazines. For this purpose, two commercial enzyme preparations with endoglucanase and endoxylanase activities (Viscozyme Wheat from Aspergillus oryzae and Ultraflo L from Humicola insolens, Novozymes) and a commercial laccase (NS51002 from Trametes villosa, Novozymes), the latter in the presence of synthetic or natural (lignin-related) mediators, were evaluated. The enzymatic treatments were studied at the laboratory scale using a standard chemical deinking sequence consisting of a pulping stage; an alkaline stage using NaOH, sodium silicate and fatty acid soap; and a bleaching stage using hydrogen peroxide. The handsheets were then prepared and their brightness, residual ink concentration, and strength properties were measured. Among the different enzymatic treatments assayed, both carbohydrate hydrolases were found to deink the secondary fibers more efficiently. Brightness increased up to 3-4% ISO on newspaper fibers, being Ultraflo 20% more efficient in the ink removal. Up to 2.5% ISO brightness increase was obtained when magazine fibers were used, being Viscozyme 9% more efficient in the ink removal. Regarding the laccase-mediator system, alone or in combination with carbohydrate hydrolases, it was ineffective in deinking both newspaper and magazine fibers, resulting in pulps with worse brightness and residual ink concentration values. However, pulp deinking by the laccase-mediator system was displayed when secondary fibers from printed cardboard were used, obtaining up to 3% ISO brightness increase and lower residual ink concentrations. [ABSTRACT FROM AUTHOR]

Abstract: The recovery and utilization of recovered paper have increased over past decades all over the world due to economic, environmental, and social issues. However, it is well known that an extended recovered paper collection is detrimental to its quality, either by the exploitation of lower quality sources such as households, or the spreading of commingled systems instead of selective collection systems. The influence of these two factors was assessed by analyzing the quality of different recovered paper grades used as raw material in a mill located in Madrid (Spain) producing newsprint and light weight coated paper from recovered paper. Part 1 of the paper deals with the impact of increased collection rates on the quality of recovered paper and Part 2 with the use of commingled collection systems. Results of Part 1 show that increased collection rates have a large impact on the quality of the recovered paper. The quality, measured as total unusable material and moisture contents, had deteriorated very rapidly in only 4years (2005–2008) as a consequence of increased collection rates. Collection rates increased in Spain from 58.5% to 68.6% during this period, resulting in more than 50% increase of total unusable material and 25% of moisture content. The downgrading of the quality of recovered paper is one of the major threats for extending the current limits of paper recycling. Therefore, future challenge is to increase its availability but maintaining its quality. [Copyright &y& Elsevier]

Activating K-RAS mutations are the most frequent oncogenic mutations in human cancer. Numerous downstream signaling pathways have been shown to be deregulated by oncogenic K-ras. However, to date there are still no effective targeted therapies for this genetically defined subset of patients. Here we report the results of a small molecule, synthetic lethal screen using mouse embryonic fibroblasts derived from a mouse model harboring a conditional oncogenic K-rasG12D allele. Among the >50,000 compounds screened, we identified a class of drugs with selective activity against oncogenic K-ras-expressing cells. The most potent member of this class, lanperisone, acts by inducing nonapoptotic cell death in a cell cycle- and translation-independent manner. The mechanism of cell killing involves the induction of reactive oxygen species that are inefficiently scavenged in K-ras mutant cells, leading to oxidative stress and cell death. In mice, treatment with lanperisone suppresses the growth of K-ras-driven tumors without overt toxicity. Our findings establish the specific antitumor activity of lanperisone and reveal oxidative stress pathways as potential targets in Ras-mediated malignancies. [ABSTRACT FROM AUTHOR]

Despite the high prevalence and poor outcome of patients with metastatic lung cancer the mechanisms of tumour progression and metastasis remain largely uncharacterized. Here we modelled human lung adenocarcinoma, which frequently harbours activating point mutations in KRAS and inactivation of the p53 pathway, using conditional alleles in mice. Lentiviral-mediated somatic activation of oncogenic Kras and deletion of p53 in the lung epithelial cells of KrasLSL-G12D/+;p53flox/flox mice initiates lung adenocarcinoma development. Although tumours are initiated synchronously by defined genetic alterations, only a subset becomes malignant, indicating that disease progression requires additional alterations. Identification of the lentiviral integration sites allowed us to distinguish metastatic from non-metastatic tumours and determine the gene expression alterations that distinguish these tumour types. Cross-species analysis identified the NK2-related homeobox transcription factor Nkx2-1 (also called Ttf-1 or Titf1) as a candidate suppressor of malignant progression. In this mouse model, Nkx2-1 negativity is pathognomonic of high-grade poorly differentiated tumours. Gain- and loss-of-function experiments in cells derived from metastatic and non-metastatic tumours demonstrated that Nkx2-1 controls tumour differentiation and limits metastatic potential in vivo. Interrogation of Nkx2-1-regulated genes, analysis of tumours at defined developmental stages, and functional complementation experiments indicate that Nkx2-1 constrains tumours in part by repressing the embryonically restricted chromatin regulator Hmga2. Whereas focal amplification of NKX2-1 in a fraction of human lung adenocarcinomas has focused attention on its oncogenic function, our data specifically link Nkx2-1 downregulation to loss of differentiation, enhanced tumour seeding ability and increased metastatic proclivity. Thus, the oncogenic and suppressive functions of Nkx2-1 in the same tumour type substantiate its role as a dual function lineage factor. [ABSTRACT FROM AUTHOR]

Mixtures of stickies-containing and stickies-free pulps were investigated for their deposition potential in an attempt to better understand the interactions of dissolved and colloidal material (DCM) when mixing two different pulps. The filtered pulp mixtures were tested in a deposition apparatus which measures both the dynamic fluid as well as impact deposition by an established optical scanning method. A pulp filtrate of model stickies led to deposition according to the proportion of stickies-containing pulp in the mixture. Other mixtures of pulps, however, led to deposition that differed from the predicted value. It is theorised that pulp fibres present in the mixture could adsorb the polysaccharides that would otherwise keep the colloidal system electrostatically stable. This destabilisation was most prominent at lower proportions of the stickies-free pulp suspensions used for mixing. These results show that care must be taken when mixing different pulps for paper and board production, as even a small amount of replacement pulp can lead to destabilisation of DCM and formation of deposits. Furthermore, special care must be taken when mixtures of pulps are used to validate stickies measurements. [ABSTRACT FROM AUTHOR]

Abstract: The multiaxial fatigue behaviour of a short glass fibre reinforced polyamide 6.6 (PA66-GF35) is investigated on hollow tubular specimens in the range of fatigue lives between 102 and 107 cycles. Fatigue experiments included pure tension, pure torsion, combined tension–torsion at different biaxiality ratios and phase shifting angles between the stress components. Tests were carried out with load ratio R =0 and R =−1 at room temperature as well as at 130°C. The influence of biaxiality ratio, phase angle between load components and load ratio is discussed. An extensive analysis of the fracture behaviour is performed on the specimens to recognise the crack nucleation and propagation mechanisms; failure modes were evaluated via optical and scanning electron microscopy. [Copyright &y& Elsevier]

Abstract: Studies on denudation rates can provide insight into the influence of climate change, tectonics, and human activities on landscape evolution. Research performed in Central Italy has shown considerable spatial variability of denudation rates in the major river basins. These studies have focused mainly on the Tyrrhenian side of the Italian peninsula, where Plio-Pleistocene marine deposits filling NW–SE elongated sedimentary basins have been uplifted during the Quaternary up to several hundreds of meters above present sea level. Small sub-catchments developed on clays are affected by sharp- and/or rounded-edged badlands (i.e. calanchi and biancane), representing denudation “hot spots” in the present-day morphoclimatic framework. In this paper, we analyze the relationships between indirectly estimated denudation rates at the catchment scale and field monitoring data at the hillslope scale. We attempt to better understand and quantify all hillslope processes that contribute to seasonal variability of denudation, to help with predicting the net input from “hot spots” to the overall estimated sediment yield at the basin outlets. At the hillslope scale, we discuss, in particular, the variability of denudation rates at calanchi and biancane badlands as a function of their different morphoevolution. [Copyright &y& Elsevier]

• By-product of Kombucha beverage as a resource of active materials. • Symbiotic Community Of Bacteria and Yeast SCOBY produced bacterial cellulose films. • Sugared herbal infusions provided the nutrients for cellulose synthase activation. • Kombucha native films showed high mechanical strength and low elongation at break. • Films from Kombucha fermented in yerba mate presented high antioxidant capacity. The symbiotic community of bacteria and yeast (SCOBY) of Kombucha beverage produces a floating film composed of bacterial cellulose, a distinctive biobased material. In this work, Kombucha fermentation was carried out in six different herbal infusions, where SCOBY was able to synthesise cellulosic films. Infusions of black and green tea, yerba mate, lavender, oregano and fennel added with sucrose (100 g/l) were used as culture media. In all cultures, film production resulted in a maximum after 21 days. Yield conversion, process productivity and antioxidant activity were quantified. Macroscopic and microscopic features of films were determined based on electronic microscopy, calorimetric and mechanical properties and hydration behaviour. Native films from yerba mate had a remarkable antioxidant activity of 93 ± 4% of radical inhibition due to plant polyphenols, which could prevent food oxidation. Results revealed that films retained natural bioactive substances preserving important physicochemical properties, essential for developing active materials. [ABSTRACT FROM AUTHOR]

Summary: Introduction: The aim of the study was to analyze the data of the NUAGES survey (a survey on the practice of nebulization in France), concerning the prescriptions of nebulized steroids from 514 pediatricians. Material and methods: The reason why nebulization was chosen as a delivery route, the diseases motivating the prescription, the age of the patients, the kind of drug used, and the prescription and device modalities were studied. Results: Efficacy in treating various respiratory diseases was the main reason cited for using nebulization, in particular severe persistent asthma (76%). Pediatricians prescribed nebulization mainly to infants (60%). The most frequently used drug was budesonide suspension (89%), but the intravenous route for steroids (18%) and drug admixtures (62%) were also proposed by nebulization. A specific prescription for the nebulizer was given in 75% of the cases, with the type of interface to use specified in 66%. Discussion: Pediatricians consider that nebulization is well adapted to young children. Although the proper steroid is usually chosen, unfortunately, it is often prescribed with other drugs, with 1 prescription out of 4 not following the recommendations. Prescription of the device is not optimal and may compromise the efficacy of the treatment. Conclusion: Nebulization is a potential mode of delivery for steroids that is difficult to prescribe and warrants improved pediatrician training. [Copyright &y& Elsevier]

The article presents a study which elucidates the role of CD72 in the modulation of B cell receptor (BCR)-mediated tolerogenic signaling and peripheral B cell tolerance through a murine model. The study concludes that CD72 is required to maintain B cell anergy and functions as a regulator of peripheral B cell tolerance. Moreover, altered CD72 expression may play a dominant role in the pathogenesis of several autoimmune diseases, including systematic lupus erythematosus and multiple sclerosis.

At critical times in development, cells are able to convert graded signals into discrete developmental outcomes; however, the mechanisms involved are poorly understood. During thymocyte development, cell fate is determined by signals originating from the αβ T-cell receptor. Low-affinity/avidity interactions between the T-cell receptor and peptide–MHC complexes direct differentiation to the single-positive stage (positive selection), whereas high-affinity/avidity interactions induce death by apoptosis (negative selection). Here we show that mice deficient in both calcineurin and nuclear factor of activated T cells (NFAT)c2/c3 lack a population of preselection thymocytes with enhanced ability to activate the mitogen-activated protein kinase (Raf–MEK–ERK) pathway, and fail to undergo positive selection. This defect can be partially rescued with constitutively active Raf, indicating that calcineurin controls MAPK signalling. Analysis of mice deficient in both Bim (which is required for negative selection) and calcineurin revealed that calcineurin-induced ERK (extracellular signal-regulated kinase) sensitization is required for differentiation in response to ‘weak’ positive selecting signals but not in response to ‘strong’ negative selecting signals (which normally induce apoptosis). These results indicate that early calcineurin/NFAT signalling produces a developmental period of ERK hypersensitivity, allowing very weak signals to induce positive selection. This mechanism might be generally useful in the discrimination of graded signals that induce different cell fates. [ABSTRACT FROM AUTHOR]

Summary: Development and repair of the vertebrate skeleton requires the precise coordination of bone-forming osteoblasts and bone-resorbing osteoclasts. In diseases such as osteoporosis, bone resorption dominates over bone formation, suggesting a failure to harmonize osteoclast and osteoblast function. Here, we show that mice expressing a constitutively nuclear NFATc1 variant (NFATc1nuc) in osteoblasts develop high bone mass. NFATc1nuc mice have massive osteoblast overgrowth, enhanced osteoblast proliferation, and coordinated changes in the expression of Wnt signaling components. In contrast, viable NFATc1-deficient mice have defects in skull bone formation in addition to impaired osteoclast development. NFATc1nuc mice have increased osteoclastogenesis despite normal levels of RANKL and OPG, indicating that an additional NFAT-regulated mechanism influences osteoclastogenesis in vivo. Calcineurin/NFATc signaling in osteoblasts controls the expression of chemoattractants that attract monocytic osteoclast precursors, thereby coupling bone formation and bone resorption. Our results indicate that NFATc1 regulates bone mass by functioning in both osteoblasts and osteoclasts. [Copyright &y& Elsevier]

Trisomy 21 results in Down's syndrome, but little is known about how a 1.5-fold increase in gene dosage produces the pleiotropic phenotypes of Down's syndrome. Here we report that two genes, DSCR1 and DYRK1A , lie within the critical region of human chromosome 21 and act synergistically to prevent nuclear occupancy of NFATc transcription factors, which are regulators of vertebrate development. We use mathematical modelling to predict that autoregulation within the pathway accentuates the effects of trisomy of DSCR1 and DYRK1A, leading to failure to activate NFATc target genes under specific conditions. Our observations of calcineurin-and Nfatc-deficient mice, Dscr1- and Dyrk1a–overexpressing mice, mouse models of Down's syndrome and human trisomy 21 are consistent with these predictions. We suggest that the 1.5-fold increase in dosage of DSCR1 and DYRK1A cooperatively destabilizes a regulatory circuit, leading to reduced NFATc activity and many of the features of Down's syndrome. More generally, these observations suggest that the destabilization of regulatory circuits can underlie human disease. [ABSTRACT FROM AUTHOR]

Abstract: To complete a series of studies on the expression of substance P and neurokinin receptors in mammalian retinas, we investigated the occurrence of these molecules in developing mouse retinas and in retinas of mice with genetic deletion of the neurokinin 1 receptor, the preferred substance P receptor. Using semi-quantitative reverse transcription–polymerase chain reaction, we measured detectable levels of the γ isoform of preprotachykinin A (a substance P precursor) mRNA at postnatal day 4. Neurokinin 1 receptor and neurokinin 3 receptor mRNAs were also detected at postnatal day 4. While γ preprotachykinin A and neurokinin 1 receptor mRNA levels significantly increased up to eye opening (postnatal day 11), neurokinin 3 receptor mRNA levels remained constant throughout development. Substance P, neurokinin 1 receptor and neurokinin 3 receptor immunoreactivities were present at postnatal day 5. Substance P was in amacrine cells, neurokinin 1 receptor in developing amacrine and bipolar cells and neurokinin 3 receptor in OFF-type cone bipolar cells. Interestingly, a transient increase in the density of neurokinin 1 receptor immunoreactive processes was observed at eye opening in lamina 3 of the inner plexiform layer, suggesting a role of substance P and neurokinin 1 receptor in this developmental phase. However, in neurokinin 1 receptor knockout retinas, besides a significant increase of the γ preprotachykinin A mRNA levels, no major changes were detected: neurokinin 3 receptor mRNA levels as well as substance P and neurokinin 3 receptor immunostainings were similar to wild types. Together with previous studies, these observations indicate that there are major differences in neurokinin 1 receptor expression patterns among developing mammalian retinas. The observations in neurokinin 1 receptor knockout mice may not be applicable to rats or rabbits, and substance P and neurokinin 1 receptor may play different developmental roles in different species. [Copyright &y& Elsevier]

Summary: A series of signal-directed transitions regulates the development of distinct populations of self-tolerant B cells and ultimately the production of antibody-producing plasma cells. We studied the role of calcineurin/NFAT signaling in B cells by deleting the regulatory b1 subunit of calcineurin specifically in B cells. Follicular (FO) and marginal zone (MZ) B cells develop normally in these mice, but B1 cell numbers are reduced. In vitro, calcineurin b1-deficient B cells have a cell-intrinsic proliferation defect downstream of the B cell receptor. These mice have higher total serum IgM despite the absence of B1 cells and have enhanced T cell-independent-1 responses. Conversely, mice with calcineurin b1-deficient B cells develop larger germinal centers and have reduced plasma cell development and antigen-specific antibody production during T cell-dependent immune responses. By several different criteria, calcineurin is dispensable for B cell tolerance, indicating that this phosphatase complex modulates immunogenic, but not tolerogenic, responses in vivo. [Copyright &y& Elsevier]

Abstract: Due to trends in papermaking like closed water systems or higher use of recovered paper (RP) as a raw material, a large number of contaminants are accumulated in the system as dissolved and colloidal material (DCM). When the DCM is destabilised by a sudden change in the system conditions, it produces sticky deposits, called secondary stickies that affect the papermaking processes and the quality of the final product. The existing laboratory methods to predict DCM destabilisation have limitations such as low reproducibility or they do not distinguish between sticky and non-sticky materials or high volumes are necessary to perform the test. In order to solve these problems, a methodology to predict the depositability potential of DCM has been developed by the Complutense University of Madrid. The methodology incorporates the destabilisation of the DCM by polymer addition, DCM deposition on collector surfaces and the quantification of the formed deposits by image analysis. Results show that the methodology has good reproducibility with a margin of error less than 10%. The methodology was applied to study: the potential of different formulations of adhesives to form stickies; the formation of deposits with different contaminant types and several concentrations; the efficiency of deposit control agents and the behaviours of different recovered paper grades. [Copyright &y& Elsevier]

The physico-chemical behavior of asphaltene is very useful to assist prediction and control the mechanisms of asphaltene deposition during the production of petroleum fluids. It has been realized that the first step in the formation of precipitated asphaltene particles is the self-aggregation mechanism to form colloidal particles or pseudo-micelles in several solvents. In this work, the critical micelle concentration (CMC) of two asphaltene fractions extracted from vacuum residues (VR) were obtained by surface tension measurements, using aromatic solvents. The molecular weight (1094-565 g/mol), calculated from average radii of the asphaltene molecules adsorbed at the air–solvent interface, are also in agreement with the values for small aggregates reported using small angle X-ray scattering. [ABSTRACT FROM AUTHOR]

We investigated the expression of the substance P (SP) receptor (the neurokinin 1 receptor, NK1 receptor) and SP functional effects in developing rabbit retinas. NK1 receptors in adult retinas were in a population of cone bipolar cells and in dopaminergic amacrine cells, as previously described. In contrast, at birth and at postnatal day (PND) 6, NK1 receptors were exclusively expressed by cholinergic amacrine and displaced amacrine cells. NK1 receptor expression in cholinergic cells was still observed at PND10 (eye opening), while at PND21 it was confined to cholinergic cells of the inner nuclear layer. Starting at PND10, NK1 receptors were also in bipolar cells and in dopaminergic amacrine cells. A fully mature NK1 receptor expression pattern was observed at PND35. Dopamine release was assessed in isolated retinas in the presence of SP, the NK1 receptor agonist GR73632 or the NK1 receptor antagonist GR82334. At PND35, extracellular dopamine was significantly increased by 10 μM SP or 0.01–100 μM GR73632, and it was decreased by 0.01–10 μM GR82334. No effects were detected in developing retinas up to PND21. Ca2+ imaging experiments were performed in single cholinergic cells identified by their “starburst” morphology in perinatal retinas. Intracellular Ca2+ levels were significantly increased by 1 μM SP or GR73632. This effect was reversibly inhibited by 1 μM GR82334. These data demonstrate that both NK1 receptor expression and SP physiological actions are developmentally regulated in the retina. SP neurotransmission in the immature retina may subserve developmental events, and SP is likely to represent an important developmental factor for the maturation of retinal neurons and circuitries. [Copyright &y& Elsevier]

During development, discrete cell fates often result from variation in the intensity of a particular signal. The mechanisms underlying these seemingly analog-to-digital switches are not understood. In developing T lymphocytes, low-intensity signals through the antigen receptor result in positive selection while more intense signals give rise to negative selection. By deleting the genetic locus encoding the regulatory B1 subunit of calcineurin specifically in thymocytes, we found an absolute requirement for calcineurin in positive selection. In contrast, calcineurin activity was dispensable in several models of negative selection. Unexpectedly, we found that removal of calcineurin activity from thymocytes results in inefficient ERK activation at the double-positive stage of thymocyte development, when selection occurs. These studies clarify the mechanism by which graded signals are converted to discrete outcomes in T cell development and further indicate that the developmental roles of calcineurin likely contribute to immunosuppression by calcineurin inhibitors. [Copyright &y& Elsevier]

A study was carried out on the effects of a fungal strain on Carrara marble specimens in cultural experiments. The fungal strain, isolated from Pisa Tower, was identified as Sporotrichum genus. After 8 months’ incubation at 28 °C, an orange–brown film was formed. The FT-IR analysis of the film showed the presence of bi-hydrate calcium oxalates. A semi-quantitative evaluation was made by term-gravimetric analysis showing that the film composition was 66% oxalate, 16% calcite, a significant amount of phosphate and a low amount of nitrates. [Copyright &y& Elsevier]

The modulation of intracellular calcium ion concentration, [Ca2+]i, is a common signalling mechanism used in many biological systems. B and T lymphocytes rely on Ca2+ signalling to initiate both developmental and activation programs. Recent data has shed new light on the initiation of this signalling pathway, the connection between the release of intracellular Ca2+ stores and the influx of extracellular Ca2+, and the molecular identity of the elusive Ca2+ release-activated Ca2+ (CRAC) channel. In addition, recent gene profiling of T lymphocytes has identified the genes that are controlled by [Ca2+]i and the Ca2+-dependent phosphatase calcineurin. [Copyright &y& Elsevier]

A descriptive multivariate assay is described which is suitable to analyze results of a biological experiment with small sample size but high qualitative and quantitative complexity of variables. This type of assay allows evaluation of multiple variables observed in the course of an experimental virus infection (e.g. viremia, nucleic acid detection, antibody titers, clinical parameters, anti-microbial treatments or vaccination) in a single graph. In our study, a multiple correspondence analysis (MCA) was used to correlate a total of 145 measurements from each of a dozen of variables measured in five groups of three cats infected by five isolates of feline immunodeficiency virus (FIV). Three groups of virus isolates with distinct virulence were defined and correlation between dynamics of lymphocyte subset counts and viral virulence was established. Comparison between the primary stages of illness and follow-up examinations were of prognostic value and are thus helpful for development and monitoring of therapeutic strategies. [Copyright &y& Elsevier]

The standard ( po = 0.1 MPa) molar enthalpies of formation for 2-, 3-, and 4- trans -methoxycinnamic acids in the gaseous phase were derived from the standard molar enthalpies of combustion in oxygen of the crystalline compounds determined by static bomb combustion calorimetry atT = 298.15 K and from the literature values for the respective enthalpies of sublimation. [Copyright &y& Elsevier]

Personal Construct Theory (Kelly, 1955) provided a framework in which the congruence of social perceptions was examined Triads of close acquaintances engaged in personality description procedures presented at two levels of abstraction (global and specific) Using a modification of Kelly's (1955) Role Construct Repertory Test (REP) grid methodology, target persons in each triad generated personally relevant self-constructs, contexts in which such self-constructs might be displayed, and actions which might be expressive of those self-constructs This resulted in an idiographic data base on which peers attempted to construe the target's personality in a variety of contexts The relationships between several self-construct system properties (such as Meaningfulness and Prototypicality) and congruence (shared construing) were assessed Patterns of correlational analyses indicated that the most meaningful self-constructs (i e , those manifested in extreme form), as well as self-constructs exhibiting the least variation across contexts, produced greater agreement among triad members about the target's personality It was suggested that the study of self-peer congruence is feasible using idiographic, self-identified personality themes, explicit contextual information, and a systems perspective [ABSTRACT FROM AUTHOR]

Beef cows in the southeastern United States are likely maintained on pasture during mid-gestation, a critical period for fetal development of traits important to performance of the growing/finishing calf. Climate projections are for increased warming with highly variable precipitation in this region. Forage quantity and quality are affected by temperature and precipitation. Thus, in order to obtain a better understanding of downstream effects from cow nutrition during gestation on subsequent performance of growing cattle, we analyzed 579 records of crossbred steers and heifers born (fall and winter) to cows grazing typical forages in Overton, Texas. Cows were involved in a long-term stocking rate study and were assigned to either high (H; 4 cow/calf ha-1) or low (L; 2 cow/calf ha-1) treatment groups. Cow body condition scores (BCS; 1-9) were collected at breeding and weaning. Calves produced were pastured from weaning to approximately 1 to 1.5 yr of age, then shipped to a commercial feedlot and subsequently slaughtered at a commercial facility. Calf data included birth weight, weaning weight (~240 d), yearling weight, on-feed weight, final pre-harvest weight, hot carcass weight (all weights in kg), dressing percentage, marbling score, yield grade, backfat thickness (cm), ribeye area (cm²), and kidney-pelvic-heart fat (%). Differences (P < 0.05) between treatment groups were determined by a general linear model in SAS with stocking rate as the main effect. Mean separation was accomplished using Tukey's test. Cow BCS (H; 4.27 ± 0.06 vs L; 5.64 ± 0.07, P < 0.0001), final pre-harvest weight (H; 594.80 ± 6.18 kg vs L; 619.85 ± 6.12 kg, < 0.005), hot carcass weight (H; 366.60 ± 3.89 kg vs L; 383.17 ± 3.74, P < 0.003), and ribeye area (H; 90.52 ± 0.90 cm2 vs L; 93.74 ± 1.03 cm2, P < 0.03) were all lower in H than L. Calf weaning weight followed a similar trend (H; 289.24 ± 2.58 kg vs L; 296.56 ± 3.08 kg, P < 0.07). Diminished nutritional provision to the fetus during mid-gestation was apparently manifest as epigenetic effects on offspring performance. [ABSTRACT FROM AUTHOR]

Material databases of plastics are becoming more and more the focus of applied science and commercial use in industry. Material properties of material manufacturers are often provided in publicly accessible material databases, which usually contain processing and mechanical properties under static loadings. Fatigue strength values are usually not accessible. The fatigue data for thermoplastics is of particular interest, as these materials have a particularly high lightweight construction potential and can be processed with a high degree of automation and reproducibility. Individual fatigue strength parameters for a specific material, environmental condition, geometry and loadings have been investigated in numerous publications. However, no work has been found in which fundamental interactions of different materials, environmental conditions, geometries and loadings on the course of the S/N-Curve have been investigated. In this paper, different effect relationships between temperature, filler type and filler content, fiber orientation and load ratio will be presented for the material Polypropylene (PP). A fatigue strength database of 11 different material manufacturers, from 71 different S/N-Curves with 606 tested samples, serves as a basis. The fatigue database enables a digital twin, which is used for the design of structural components to add a third dimension with artificial intelligence, and which is trained by an engineer. From the determined effect relationships, fatigue factors are to be derived and can be used to evaluate the fatigue strength of a component in the design process and to train the digital twin. The fatigue-strength values from the database also allow a statistical consideration of the slope k and the scattering of the S/N-Curve. The different S/N-Curves are transferred into a Haigh diagram, from which the functional course of the mean stress is determined. • Fatigue database of Polymers. • Influencing fatigue parameter Temperature, fibre orientation, filler content. • Mean stress dependency of Polypropylene in Haigh-Diagram. • Compendium of Fatigue Factors for Polypropylene. • Fatigue Factors input data for artificial intelligence. [ABSTRACT FROM AUTHOR]

• Aspect ratio of highly fibrillated nanocellulose is estimated using the gel point methodology. • Crystal Violet dyes nanocellulose improving the sediment visualization. • Controlling sedimentation time is essential for consistent gel point measurement. • Flocculation is not required to determine gel point of charged nanocellulose. The characterization of nanocellulose fibres (NC) length is a difficult and indirect measurement which relies on aspect ratio calculation and fibre diameter analysis. The aspect ratio can be directly calculated from the gel point, a parameter obtained from sedimentation experiments. The gel point has been used with macroscopic fibres and microfibrillated cellulose, that easily sediment by gravity. However, this methodology has not yield consistent results with highly charged nanofibres nor with fibres with sediment layer difficult to observe. In this study, the gel point methodology is modified: 1) dying the fibres with Crystal Violet to enable the visualization of the fibrils sedimentation line without affecting the fibre network; and 2) by optimizing the sedimentation time to ensure complete settling. The two types of fibrils characterized -low and high fibrillated NC (LF-NC, HF-NC)- behave differently due to the slower sedimentation of HF-NC. The time to reach a stable sedimented layer increases with the level of fibre fibrillation, the charge and the decrease of fibre dimension. Reproducible gel point can be measured after 2 days for LF-NC; however, 8 days are required for HF-NC. The modified methodology was validated by quantifying the influence of pH and salt concentration. As expected, low pHs and the addition of CaCl 2 coagulate HF-NC into flocs which increase the ratio: final over initial fibres height (H s /H o); this decreases significantly the gel point, as a lower amount of HF-NC are required to interconnect all fibres. This modified method is a valuable tool for the accurate dimensional characterisation of highly charged and low diameter cellulose nanofibres. [ABSTRACT FROM AUTHOR]

Recycling cycles cause a decrease in mechanical paper properties due to cellulose fiber degradation. The use of cellulose micro/nanofibers (CMF/CNF) to reinforce paper strength has been well studied, although it has been found to have negative effects on drainage. However, the application of CMF/CNF as paper reinforcement is affected by the nanocellulose type. Thus in this study mechanical and chemical treatments in CNF production were compared. Old corrugated container (OCC) pulp used to produce recycled cartonboard was reinforced with 1) CMF from never-dried northern bleached softwood kraft pulp (NBSK) highly refined in a 16-inch low consistency refiner at 1200 rpm and 25 kW of net power; and 2) CNF from NBSK pulp treated by TEMPO-mediated oxidation and homogenization at 600 bars. CMF/CNF and OCC were pulped at the same time and handsheets formed with cationic starch (CS) as retention system. Mechanical, drainage and flocculation properties were evaluated and compared. Data were also compared with other sources of TEMPO CNF. Results show an improvement in mechanical properties, drainage and flocculation when OCC is reinforced with CMF obtained with LCR. Therefore, high fibrillation was not necessary to improve mechanical paper or cardboard properties. [ABSTRACT FROM AUTHOR]

Introduction et but de l’étude Le groupe pluridisciplinaire « Manger en réanimation pédiatrique : du soin au plaisir », au sein de la réanimation pédiatrique de Lyon, a comme objectif de réhabiliter l’alimentation orale au statut de soin, promouvoir le plaisir de manger chez le patient, de susciter également du plaisir pour la famille et les soignants à donner à manger à l’enfant. Ce projet s’inspire des « soins de développement » de la néonatologie et du « Mieux vivre la réanimation » de l’adulte, afin de réduire les syndromes post-traumatiques. Matériel et méthodes Nous avons réalisé une étude d’évaluation des pratiques professionnelles en trois phases. La phase pré-interventionnelle (janvier–mars 2014) avait pour objectif, d’une part, le recensement des moyens : matériel (vaisselle, couverts, etc.), installation (chaise hautes, tables, etc.), alimentation proposée (quantité, qualité), et d’autre part, de mener une enquête auprès de l’équipe soignante, des enfants et de leurs parents : questionnaires abordant le rapport des soignants à l’alimentation orale en tant que soin puis en tant que plaisir, et les rapports de l’enfant et de sa famille en tant que plaisir. Les questions portent sur des notions théoriques, sur le vécu et le ressenti des pratiques ainsi que sur les attentes. La phase interventionnelle (juin–octobre 2014) avait pour objectif la sensibilisation de l’équipe sur la base des résultats de la phase pré-interventionnelle. Enfin, en phase post-interventionnelle (mars–juillet 2015), une nouvelle enquête a été réalisée selon les mêmes modalités que lors de la phase pré-interventionnelle. Résultats Pour la phase pré-interventionnelle, 86 questionnaires soignants sur 95 ont été récupérés (91 %) ainsi que 55 questionnaires familles sur 58 (95 %) (40 % d’enfants de moins de 18 mois). Lors de la phase interventionnelle, dix soignants ont participés à la formation de l’institut Paul-Bocuse « Accueil et service des repas en unité de soins » spécifique aux services pédiatriques : Arts de la table, dimensions environnementales et sociales du repas, qualité du service, rôle du langage et des gestes dans la relation de service, comportement alimentaire de l’enfant et le développement du goût, notion de plaisir. Un classeur de soutien reprenant les moments forts de la formation, un livret humoristique « phrases chocs » a été mis en place pour les soignants. Un investissement matériel (vaisselle, chaises hautes,…), adapté aux enfants a été fait. Et une exposition photo d’enfants alimentés en réanimation pédiatrique a été organisée. En phase post-interventionnelle, 74 questionnaires soignants sur 84 ont été récupérés (88 %) ainsi que 39 questionnaires familles sur 40 (98 %) (20 % d’enfants de moins de 18 mois). Nous notons une augmentation de l’intégration de l’alimentation orale en tant que soin, chez les soignants, de 13 % ; du plaisir ressenti par l’enfant de 26 % selon les soignants et 29 % selon les parents ; du plaisir ressenti par les soignants de 50 % ; l’intégration de la famille dans le temps du repas de 22 % ; des scores de satisfaction globale de 24 % chez les soignants et de 10 % chez les enfants et leurs familles. Conclusion Notre étude confirme l’efficacité de ce type d’approche dans l’amélioration des pratiques et permet de redonner une dimension de plaisir à un soin habituellement technique auprès des soignants, des patients et de leurs parents. Cette méthodologie est transposable aux autres unités de soins pédiatriques. [ABSTRACT FROM AUTHOR]

In this paper, a capillary underwater discharge, that is sustained with direct current (dc) voltages upto 30 kV (20 mA), is investigated. In a capillary discharge scheme, the current is, at some point along its path between two submerged electrodes, flowing through a narrow elongated bore in a dielectric material. When the current density is sufficiently high, local boiling and subsequent vapor breakdown results in the formation of a plasma within this capillary. Spectroscopic measurements indicate that this kind of discharge is an efficient source of ultraviolet radiation (280-320 nm). Discharge images reveal that the plasma is initiated half way the capillary and that during plasma expansion, the anode and cathode plasma-liquid boundaries have markedly different velocities. [ABSTRACT FROM AUTHOR]

The article reports that Calcium ions (Ca 2+) may be the most widely used second messenger molecules in biology. Indeed, Ca 2+ is essential for early development of organisms, immune responses, and even for remembering what you are about to read. The diverse tasks of Ca 2+ raise the question of the molecular origins of specific Ca 2+ responses. Researchers identify new players that regulate the movement of Ca 2+ into and out of cells, providing a more complete understanding of Ca 2+ responses in the immune system. Activation of the T cell receptor by ligand initiates a rapid influx of Ca sup 2+ into T cells.

Cancer genomes are almost invariably complex with genomic alterations cooperating during each step of carcinogenesis. In cancers that lack a single dominant oncogene mutation, cooperation between the inactivation of multiple tumor suppressor genes can drive tumor initiation and growth. Here, we shed light on how the sequential acquisition of genomic alterations generates oncogene-negative lung tumors. We couple tumor barcoding with combinatorial and multiplexed somatic genome editing to characterize the fitness landscapes of three tumor suppressor genes NF1, RASA1, and PTEN, the inactivation of which jointly drives oncogene-negative lung adenocarcinoma initiation and growth. The fitness landscape was surprisingly accessible, with each additional mutation leading to growth advantage. Furthermore, the fitness landscapes remained fully accessible across backgrounds with the inactivation of additional tumor suppressor genes. These results suggest that while predicting cancer evolution will be challenging, acquiring the multiple alterations that drive the growth of oncogene-negative tumors can be facilitated by the lack of constraints on mutational order. [ABSTRACT FROM AUTHOR]

The combination of complementary techniques in the characterization of catalysts under working conditions is a very powerful tool for an accurate and in‐depth comprehension of the system investigated. In particular, X‐ray absorption spectroscopy (XAS) coupled with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and mass spectroscopy (MS) is a powerful combination since XAS characterizes the main elements of the catalytic system (selecting the absorption edge) and DRIFTS monitors surface adsorbates while MS enables product identification and quantification. In the present manuscript, a new reactor cell and an experimental setup optimized to perform time‐resolved experiments on heterogeneous catalysts under working conditions are reported. A key feature of this setup is the possibility to work at high temperature and pressure, with a small cell dead volume. To demonstrate these capabilities, performance tests with and without X‐rays are performed. The effective temperature at the sample surface, the speed to purge the gas volume inside the cell and catalytic activity have been evaluated to demonstrate the reliability and usefulness of the cell. The setup capability of combining XAS, DRIFTS and MS spectroscopies is demonstrated in a time‐resolved experiment, following the reduction of NO by Rh nanoparticles supported on alumina. A new reactor cell and experimental setup designed to perform time‐resolved experiments on heterogeneous catalysts under working conditions that simulltaneously combines XAS, DRIFT and MS spectroscopies are reported. [ABSTRACT FROM AUTHOR]

Purpose To test the hypothesis that protecting retinal neurons from apoptosis elicited by diabetic stress may prevent the increase of vascular endothelial growth factor ( VEGF) in the retina. Methods Ex vivo mouse retinal explants were exposed to stressors similar to those characterizing diabetic retinopathy ( DR), i.e. high glucose ( HG), oxidative stress ( OS) or advanced glycation end-products ( AGE). Retinal cell death was antagonized with octreotide ( OCT), a somatostatin analog, and pituitary adenylate cyclase activating peptide ( PACAP), two well-documented neuroprotectants. Data were obtained with real time RT- PCR, Western blot, ELISA and immunohistochemistry. Results Control explants remained viable up to 10 days. Increased apoptosis was observed after HG, OS or AGE, and it was paralleled by increases in VEGF expression and release. Both OCT and PACAP reduced retinal apoptosis. At the same time, they also reduced VEGF expression and release. To get indications about the biological significance of VEGF release by stressed retinal cells, a VEGF trap ( VT) was administered to HG, OS or AGE treated retinal explants. The effect of the VT was to further increase cell death induced by treatments. Conclusions Protecting retinal neurons from diabetic stress also reduces VEGF expression and release, while inhibiting VEGF leads to exacerbation of apoptosis. This suggests that the retina in early DR releases VEGF as a pro-survival factor. Neuroprotective agents may decrease the need of VEGF production by the retina, therefore limiting the risk, in the long term, of pathologic angiogenesis. [ABSTRACT FROM AUTHOR]

Purpose In the retina, hypoxia is considered one of the key factors to trigger angiogenesis and to promote apoptosis by reducing photoreceptors and other retinal neurons, each of them contributing to vision loss. We recently demonstrated that the beta‐adrenergic system interferes with angiogenesis‐dependent diseases in the retina by regulating endogenous VEGF. Aim of the present study was to investigate the role of distinct beta‐adrenergic receptors (BARs)in neurodegenerative processes in response to hypoxia. Methods Ex vivo mouse retinal explants and in vivo models were used. BARs were blocked with antagonists or silenced with siRNAs. VEGFR2 was blocked with SU1498, whereas iNOs and eNOS with AG, L‐NIO or L‐NAME. mRNA levels were evaluated with quantitative RT‐PCR. BARs, iNOS, eNOS and apoptotic signals were determined with Western blot. Immunohistochemistry was used to localize BARs and to assess neovascularization. VEGF release and NO production were measured with colorimetric assays. Hoechst and TUNEL were used to evaluate cell loss. Results Among the BARs, BAR3 is localized to blood vessels, is upregulated by hypoxia and acts through iNOS/NO to control VEGF levels and degenerative responses to the hypoxic insult. In particular, BAR3 blockade is accompanied by increased levels of apoptotic signals and cell loss. Pharmacological interaction with the VEGF signalling demonstrates that BAR3 exerts a protective action on retinal cells through a modulation of endogenous VEGF. Conclusion Our findings demonstrate that modulation of BAR3 activity during ischemia may be a powerful means to achieve neuroprotection. VEGF's role in retinal cell survival has important implications for treatments with VEGF blockade within the context of ocular vascular diseases. [ABSTRACT FROM AUTHOR]

Small cell lung cancer (SCLC) is an aggressive cancer often diagnosed after it has metastasized. Despite the need to better understand this disease, SCLC remains poorly characterized at the molecular and genomic levels. Using a genetically engineered mouse model of SCLC driven by conditional deletion of Trp53 and Rb1 in the lung, we identified several frequent, high-magnitude focal DNA copy number alterations in SCLC. We uncovered amplification of a novel, oncogenic transcription factor, Nuclear factor I/B (Nfib), in the mouse SCLC model and in human SCLC. Functional studies indicate that NFIB regulates cell viability and proliferation during transformation. [ABSTRACT FROM AUTHOR]