•Walnut shells have been pyrolyzed in CO2 and N2 in TGA and fixed bed reactor.•Two parallel reactions describe the kinetics of pyrolysis and of char combustion and gasification.•Char and tar samples ...are characterized by GC–MS, elemental analyzer, TGA, SEM.•Increased CO2 concentrations has modest effects on slow biomass pyrolysis products.
Previous studies have shown that increased carbon dioxide concentration upon heat up affects the products of coal pyrolysis and in particular that chars prepared under carbon dioxide rich atmospheres are less reactive than chars prepared in nitrogen, and consistently tars are more aromatic. In the present work, this issue is investigated with reference to a biomass, namely walnut shells (WS), where the lignin component prevails over cellulose and hemicellulose.
Preliminary experiments of thermal degradation have been carried out using a thermogravimetric (TG) apparatus, under constant heating rate conditions, in flows of either nitrogen or carbon dioxide. Derivative thermogravimetric (DTG) curves reveal the existence of multiple peaks, which are typically associated with the degradation of different ligno-cellulosic components. A multiple parallel reaction scheme has therefore been used to fit the experimental data and kinetic parameters have been obtained.
Walnut shells were also pyrolyzed in a fixed bed reactor at 600 °C in either nitrogen or carbon dioxide so as to collect pyrolysis products in amounts sufficient for further analysis. Char and tar samples have been characterized using different techniques (e.g. GC–MS, elemental analysis, TGA, SEM) revealing limited differences. Combustion rates of the chars have been measured by means of non-isothermal thermogravimetric experiments in air and again small differences have been observed between the samples prepared under carbon dioxide and nitrogen.
It has been concluded that under the low heating rate conditions typical of the thermogravimetric apparatus and fixed bed reactor used in the work, the effects of carbon dioxide on liquid and solid products of biomass pyrolysis exist but are less important than for coal.
The work is complementary to another paper, which addresses the effect of carbon dioxide on biomass pyrolysis under high temperature and fast heating rate conditions in a drop tube reactor.
Episodes of high temperature at anthesis, which in rice is the most sensitive stage to temperature, are expected to occur more frequently in future climates. The morphology of the reproductive organs ...and pollen number, and changes in anther protein expression, were studied in response to high temperature at anthesis in three rice (Oryza sativa L.) genotypes. Plants were exposed to 6 h of high (38 °C) and control (29 °C) temperature at anthesis and spikelets collected for morphological and proteomic analysis. Moroberekan was the most heat-sensitive genotype (18% spikelet fertility at 38 °C), while IR64 (48%) and N22 (71%) were moderately and highly heat tolerant, respectively. There were significant differences among the genotypes in anther length and width, apical and basal pore lengths, apical pore area, and stigma and pistil length. Temperature also affected some of these traits, increasing anther pore size and reducing stigma length. Nonetheless, variation in the number of pollen on the stigma could not be related to measured morphological traits. Variation in spikelet fertility was highly correlated (r=0.97, n=6) with the proportion of spikelets with ≥20 germinated pollen grains on the stigma. A 2D-gel electrophoresis showed 46 protein spots changing in abundance, of which 13 differentially expressed protein spots were analysed by MS/MALDI-TOF. A cold and a heat shock protein were found significantly up-regulated in N22, and this may have contributed to the greater heat tolerance of N22. The role of differentially expressed proteins and morphology during anther dehiscence and pollination in shaping heat tolerance and susceptibility is discussed.
We calculate the aspect ratio of the electron diffusion region (EDR) during symmetric magnetic reconnection using magnetic field gradients measured by the Magnetospheric Multiscale (MMS) Mission. The ...technique introduced in this paper is validated using a particle‐in‐cell simulation and used to calculate the EDR aspect ratios for three MMS‐observed magnetotail EDRs which are compared with the EDR aspect ratio predicted by scaling dependencies on asymptotic upstream electron β. We then use the aspect ratio to calculate the normalized reconnection rate and show that it is within uncertainty of the normalized reconnection rate found by previous studies for three MMS‐observed EDRs. Because the magnetic field gradients are velocity‐frame independent and typically very well measured by MMS, the technique can be used to obtain the normalized reconnection rate with higher fidelity than established methods.
Plain Language Summary
Magnetic reconnection is a plasma process which occurs throughout the universe. It accelerates and heats nearby particles, and can redistribute energy over vast scales. The rate at which it occurs, the reconnection rate, is one of the most important quantities describing reconnection. Reconnection occurs within an electron‐scale region where ions and electrons are decoupled from the magnetic field, known as the electron diffusion region (EDR). Theory and simulations have shown the dimensions of the EDR scale with the reconnection rate. In this paper, we introduce a new method to determine the aspect ratio of the EDR and use it to find the reconnection rate for three EDRs observed by the Magnetospheric Multiscale Mission. This new method has fewer sources of error than established methods for determining reconnection rate using spacecraft data, and could provide a simpler way of studying the mechanisms which control the reconnection rate.
Key Points
A new technique is introduced to calculate the aspect ratio of the electron diffusion region (EDR) with magnetic field gradients
The aspect ratio is determined within 20% uncertainty for a particle‐in‐cell simulation with added MMS‐like errors
The reconnection rates from the aspect ratio and reconnection electric fields are within uncertainties during three magnetotail EDRs
Inhibition of de novo palmitate synthesis via fatty acid synthase (FASN) inhibition provides an unproven approach to cancer therapy with a strong biological rationale. FASN expression increases with ...tumor progression and associates with chemoresistance, tumor metastasis, and diminished patient survival in numerous tumor types. TVB-3166, an orally-available, reversible, potent, and selective FASN inhibitor induces apoptosis, inhibits anchorage-independent cell growth under lipid-rich conditions, and inhibits in-vivo xenograft tumor growth. Dose-dependent effects are observed between 20–200nM TVB-3166, which agrees with the IC50 in biochemical FASN and cellular palmitate synthesis assays. Mechanistic studies show that FASN inhibition disrupts lipid raft architecture, inhibits biological pathways such as lipid biosynthesis, PI3K–AKT–mTOR and β-catenin signal transduction, and inhibits expression of oncogenic effectors such as c-Myc; effects that are tumor-cell specific. Our results demonstrate that FASN inhibition has anti-tumor activities in biologically diverse preclinical tumor models and provide mechanistic and pharmacologic evidence that FASN inhibition presents a promising therapeutic strategy for treating a variety of cancers, including those expressing mutant K-Ras, ErbB2, c-Met, and PTEN. The reported findings inform ongoing studies to link mechanisms of action with defined tumor types and advance the discovery of biomarkers supporting development of FASN inhibitors as cancer therapeutics.
Fatty acid synthase (FASN) is a vital enzyme in tumor cell biology; the over-expression of FASN is associated with diminished patient prognosis and resistance to many cancer therapies. Our data demonstrate that selective and potent FASN inhibition with TVB-3166 leads to selective death of tumor cells, without significant effect on normal cells, and inhibits in vivo xenograft tumor growth at well-tolerated doses. Candidate biomarkers for selecting tumors highly sensitive to FASN inhibition are identified. These preclinical data provide mechanistic and pharmacologic evidence that FASN inhibition presents a promising therapeutic strategy for treating a variety of cancers.
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•TVB-3166 is an orally available, reversible, potent, and selective FASN inhibitor.•TVB-3166 inhibition of FASN induces apoptosis in tumor cells but not normal cells.•TVB-3166 inhibits in vivo xenograft tumor growth.•Candidate biomarkers to select tumors sensitive to FASN inhibition are identified.
The identification of an early biomarker for autism spectrum disorder (ASD) would improve the determination of risk, leading to earlier diagnosis and, potentially, earlier intervention and improved ...outcomes.
Data were generated from the Early Markers for Autism study, a population-based case-control study of prenatal and neonatal biomarkers of ASD. Newborn bloodspots of children with ASD (n = 370), children with developmental delay (n = 140), and general population (GP) controls (n = 378) were analyzed for 42 different immune markers using a Luminex multiplex platform. Comparisons of immune marker concentrations between groups were examined using logistic regression and partial least squares discriminant analysis.
Children with ASD had significantly increased neonatal levels of interleukin-6 (IL-6) and IL-8 compared with GP controls. An increase in IL-8 was especially significant in the ASD group with early onset compared with the GP group, with an adjusted odds ratio of 1.97 (95% confidence interval, 1.39–2.83; p = .00014). In addition, children with ASD had significantly elevated levels of eotaxin-1, interferon-γ, and IL-12p70 relative to children with developmental delay. We observed no significant differences in levels of immune markers between the developmental delay and GP groups.
Elevated levels of some inflammatory markers in newborn bloodspots indicated a higher degree of immune activation at birth in children who were subsequently diagnosed with ASD. The data from this exploratory study suggest that with further expansion, the development of neonatal bloodspot testing for cytokine/chemokine levels might lead to the identification of biomarkers that provide an accurate assessment of ASD risk at birth.
Rice is the principle staple crop of Asia and any deterioration of rice production systems through climate change would seriously impair food security in this continent. This review assesses spatial ...and temporal vulnerabilities of different rice production systems to climate change impacts in Asia. Initially, the review discusses the risks of increasing heat stress and maps the regions where current temperatures are already approaching critical levels during the susceptible stages of the rice plant, namely Pakistan/north India (Oct.), south India (April, Aug.), east India/Bangladesh (March-June), Myanmar/Thailand/Laos/Cambodia (March-June), Vietnam (April/Aug.), Philippines (April/June), Indonesia (Aug.) and China (July/Aug.). Possible adaptation options for heat stress are derived from regions where the rice crop is already exposed to very high temperatures including Iran and Australia. Drought stress is also expected to aggravate through climate change; a map superimposing the distribution of rainfed rice and precipitation anomalies in Asia highlights especially vulnerable areas in east India/Bangladesh and Myanmar/Thailand.
Then, the review gives emphasis to two rice growing environments that have outstanding importance for food supply in Asia and, at the same time, are particularly vulnerable to climate impacts. The mega-deltas in Vietnam, Myanmar and Bangladesh are the backbone of the rice economy in the respective country and will experience specific climate change impacts due to sea level rise. Significant improvements of the rice production systems, that is, higher resilience to flooding and salinity, are crucial for maintaining or even increasing yield levels in these very productive deltaic regions. The other ‘hotspot’ with especially high climate change risks in Asia is the Indo-Gangetic Plains (IGP) which will be affected by the melting of the Himalayan glaciers. The dominant land use type in the IGP is rice-wheat rotation, and we discuss specific vulnerabilities and possible adaptation options in the different sub-regions of the IGP. We conclude that geo-spatial vulnerability assessments may become crucial for planning targeted adaptation programs, but that policy frameworks are needed for their implementation.
DEMO is the name for the first stage prototype fusion reactor considered to be the next step after ITER towards realizing fusion. For the realization of fusion energy especially, materials questions ...pose a significant challenge already today. Heat, particle and neutron loads are a significant problem to material lifetime when extrapolating to DEMO. For many of the issues faced, advanced materials solutions are under discussion or already under development. In particular, components such as the first wall and the divertor of the reactor can benefit from introducing new approaches such as composites or new alloys into the discussion. Cracking, oxidation as well as fuel management are driving issues when deciding for new materials. Here composites as well as strengthened CuCrZr components together with oxidation resilient tungsten alloys allow the step towards a fusion reactor. In addition, neutron induced effects such as transmutation, embrittlement and after-heat and activation are essential. Therefore, when designing a component an approach taking into account all aspects is required.
▶ N22 an aus rice cultivar is a good high temperature and water deficit stress tolerant donor. ▶ High temperature at flowering stage results in cumulative linear decline in spikelet fertility. ▶ ...Physiology at flowering affected similarly with combined high temperature and water stress.
In future climates, rice could more frequently be subjected to simultaneous high temperature and water stress during sensitive developmental stages such as flowering. In this study, five rice genotypes were exposed to high temperature, water stress and combined high temperature and water stress during flowering to quantify their response through spikelet fertility. Microscopic analyses revealed significant differences in anther dehiscence between treatments and genotypes, with a moderately high association with the number of germinated pollen grains on the stigma. There was a strong relationship between spikelet fertility and the number of germinated pollen on stigmas. Although, all three stress treatments resulted in spikelet sterility, high-temperature stress caused the highest sterility in all five genotypes. A cumulative linear decline in spikelet fertility with increasing duration of independent high-temperature stress and in combination with water stress was quantified. Better anther dehiscence, higher
in vivo pollen germination, and higher spikelet fertility were observed in both the N22 accessions compared with IR64, Apo and Moroberekan under high temperature, water stress and combined stress, indicating its ability to tolerate multiple abiotic stresses.
Palmitate, the enzymatic product of FASN, and palmitate-derived lipids support cell metabolism, membrane architecture, protein localization, and intracellular signaling. Tubulins are among many ...proteins that are modified post-translationally by acylation with palmitate. We show that FASN inhibition with TVB-3166 or TVB-3664 significantly reduces tubulin palmitoylation and mRNA expression. Disrupted microtubule organization in tumor cells is an additional consequence of FASN inhibition. FASN inhibition combined with taxane treatment enhances inhibition of in vitro tumor cell growth compared to treatment with either agent alone. In lung, ovarian, prostate, and pancreatic tumor xenograft studies, FASN inhibition and paclitaxel or docetaxel combine to inhibit xenograft tumor growth with significantly enhanced anti-tumor activity. Tumor regression was observed in 3 of 6 tumor xenograft models. FASN inhibition does not affect cellular taxane concentration in vitro. Our data suggest a mechanism of enhanced anti-tumor activity of the FASN and taxane drug combination that includes inhibition of tubulin palmitoylation and disruption of microtubule organization in tumor cells, as well as a sensitization of tumor cells to FASN inhibition-mediated effects that include gene expression changes and inhibition of β-catenin. Together, the results strongly support investigation of combined FASN inhibition and taxane treatment as a therapy for a variety of human cancers.
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•FASN inhibition decreases tubulin palmitoylation and disrupts microtubules in tumor cells but not non-tumor cells•Combined FASN inhibition and taxane treatment increases inhibition of in vitro tumor cell colony growth•FASN inhibition does not affect intracellular paclitaxel concentrations•Combined FASN inhibition and taxane treatment significantly increases inhibition of tumor growth or causes regression of diverse xenograft tumors•Taxane treatment sensitizes xenograft tumors to FASN inhibition-mediated beta-catenin blockade and gene expression changes
Fatty acid synthase (FASN) is a vital enzyme in tumor cell biology; the over-expression of FASN is associated with diminished patient prognosis and resistance to many cancer therapies. Our data demonstrate that selective and potent FASN inhibition combines with taxane treatment to enhance tumor growth inhibition and induce tumor regression in varied preclinical tumor models. Mechanism-of-action studies indicate that the increased activity of the combination results from the effects of both drugs. The results support clinical investigation of combined FASN inhibition and taxane treatment as an anti-cancer therapy.
Functionally graded steel/tungsten layers may be used as interlayers in the first wall of future fusion reactors to balance thermally-induced stress peaks in the steel‑tungsten joint. In this work, a ...modified water-stabilized atmospheric plasma spraying set-up is used to deposit uniform and functionally graded steel/tungsten coatings at elevated substrate temperatures. Uniform coatings were used to characterise individual sublayers of graded coatings in detail. The thermal expansion, thermal conductivity, Young's modulus and yield strength of the layers are promising for the application in steel‑tungsten joints and can be explained by microstructural observations. Only at a substrate preheating temperature of 900 °C the formation of intermetallic precipitates during deposition was observed.
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