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River networks are critically important ecosystems. This interdisciplinary book provides an integrated ecohydrological framework blending laboratory, field, and theoretical evidence that changes our understanding of river networks as ecological corridors. It describes how the physical structure of the river environment impacts biodiversity, species invasions, population dynamics, and the spread of waterborne disease. State-of-the-art research on the ecological roles of the structure of river networks is summarized, including important studies on the spread and control of waterborne diseases, biodiversity loss due to water resource management, and invasions by non-native species. Practical implications of this research are illustrated with numerous examples throughout. This is an invaluable go-to reference for graduate students and researchers interested in river ecology and hydrology, and the links between the two. Describing new related research on spatially-explicit modeling of the spread of waterborne disease, this book will also be of great interest to epidemiologists and public health managers.
The tomato Mi-1 gene mediates plant resistance to whitefly Bemisia tabaci, nematodes, and aphids. Other genes are also required for this resistance, and a model of interaction between the proteins encoded by these genes was proposed. Microarray analyses were used previously to identify genes involved in plant resistance to pests or pathogens, but scarcely in resistance to insects. In the present work, the GeneChip™ Tomato Genome Array (Affymetrix®) was used to compare the transcriptional profiles of Motelle (bearing Mi-1) and Moneymaker (lacking Mi-1) cultivars, both before and after B. tabaci infestation. Ten transcripts were expressed at least twofold in uninfested Motelle than in Moneymaker, while other eight were expressed half or less. After whitefly infestation, differences between cultivars increased to 14 transcripts expressed more in Motelle than in Moneymaker and 14 transcripts less expressed. Half of these transcripts showed no differential expression before infestation. These results show the baseline differences in the tomato transcriptomic profile associated with the presence or absence of the Mi-1 gene and provide us with valuable information on candidate genes to intervene in either compatible or incompatible tomato–whitefly interactions.
Nanoparticles and nanopores of iron oxide were synthesized by electrochemical anodization, in an electrolytic medium of ammonium fluoride (NH4F), deionized water and ethylene glycol. After anodization, the Fe foils were annealed at 450 °C for 2 hours. Different anodization times and two concentrations of NH4F (0.1 M and 1.2 M) were evaluated, under static conditions at room temperature. Scanning Electron Microscopy showed nanopores (0.1 M) and nanoparticles (1.2 M). Eight vibration modes characteristic of α-Fe2O3 were found with Raman spectroscopy technique. Relationship between the modes Eu(LO) and 2Eu(LO) was found, therefore, their association with the disorder in the crystalline structure can be determined and it was also found that 2Eu(LO) intensity mode at a concentration of 1.2 M is larger than 0.1 M nanostructures, the FWHM of the A1g mode at 227 cm-1 corresponding to the Fe3+ ions and the Eg at 293 cm-1 mode caused by the O2- ions was also analyzed and founded that the crystalline structure of hematite can be determined by the A1g mode at 227 cm-1.
Drawing on the new institutional theory and the resources based view of the firm (RBV), this study tries to shed light upon the idea that isomorphic organizational changes seek legitimacy over efficiency. Using data from 102 Spanish companies and employing partial least squares, a variance-based structural equation modeling technique, this study concludes that both objectives are achievable simultaneously when firms implement total quality management (TQM) as an integrative stream of both theories. Furthermore, empirical results reveal that: (i) institutional pressures (IP) condition significantly the implementation of TQM, (ii) TQM exerts a double mediating role in the IP-legitimacy and IP-efficiency relationships, and (iii) both efficiency and legitimacy objectives are achieved by means of TQM. However, we observe a dual phenomenon: (i) while we find a significant positive effect of TQM on overall performance (OP) via efficiency and (ii) we failed to find support for the TQM-OP link via legitimacy.
In this work, the anodization of grade 2 titanium was performed using a HCl-based electrolyte in order to obtain Titania nanostructures. Different glycerol concentrations were added to the HCl electrolyte to study the effect it has on the shape and density of the nanostructures, additionally, anodization time and voltage was also varied. The anodized samples were observed by SEM microscopy and studied by Raman spectroscopy and X-ray diffraction. Raman spectroscopy and XRD showed the formation of the anatase phase of the TiO2. By SEM it was possible to observe several changes in the shape of the structures, by adding glycerol ball-like structures were visible, anodization time did not change the shape of the nanostructures. However, the voltage variation showed a clear control on the shape of the structures, forming nanotubes at higher voltages. It was concluded that a better control of the shape and density of the nanostructures is achieved by adding glycerol, however, in order to overcome the resistance that the electrolyte brings, higher voltages are required.
An initial mixture of raw materials (batch) typically used for the manufacture of conventional soda-lime float glass was subjected to a mechanical activation process for 30 or 60 minutes in a planetary ball mill. An intensification of the chemical reactivity of the batch, which was directly related with the increase in the milling time, was observed. This accelerated the chemical reactions that took place during the batch melting process between sodium, calcium and magnesium carbonates and other components of the mixture, which happened at significantly lower temperatures with respect to the batch without mechanical activation. The heat of fusion of the batch, estimated using a methodology previously reported in the literature, indicated that the mechanical activation given to the initial mixture of raw materials decreased the energy consumed during the batch melting. This was also evidenced by a decrease in the temperature at which the release of CO2 ended, which was considerably larger than that previously reported in the literature based solely on the decrease in the particle size of a batch of similar composition achieved by dry sieving.
We report a numerical analysis of the unforced break-up of free cylindrical threads of viscous Newtonian liquid whose interface is coated with insoluble surfactants, focusing on the formation of satellite droplets. The initial conditions are harmonic disturbances of the cylindrical shape with a small amplitude
, and whose wavelength is the most unstable one deduced from linear stability theory. We demonstrate that, in the limit
, the problem depends on two dimensionless parameters, namely the Laplace number,
, and the elasticity parameter,
are the liquid density, viscosity and initial surface tension, respectively,
is the Gibbs elasticity and
is the unperturbed thread radius. A parametric study is presented to quantify the influence of
on two key quantities: the satellite droplet volume and the mass of surfactant trapped at the satellite’s surface just prior to pinch-off,
, respectively. We identify a weak-elasticity regime,
, in which the satellite volume and the associated mass of surfactant obey the scaling law
reach a plateau of about
being in close agreement with previous experiments of low-viscosity threads with clean interfaces. For
, we reveal the existence of a discontinuous transition in
at a critical elasticity,
, such that
abruptly increase at
. The jumps experienced by both quantities reach a plateau when
, while they decrease monotonically as
increases up to
, where both become zero.
This paper provides an update and overview of the Center for Remote Sensing of Ice Sheets (CReSIS) radars and platforms, including representative results from these systems. CReSIS radar systems operate over a frequency range of 14–38 GHz. Each radar system's specific frequency band is driven by the required depth of signal penetration, measurement resolution, allocated frequency spectra, and antenna operating frequencies (often influenced by aircraft integration). We also highlight recent system advancements and future work, including (1) increasing system bandwidth; (2) miniaturizing radar hardware; and (3) increasing sensitivity. For platform development, we are developing smaller, easier to operate and less expensive unmanned aerial systems. Next-generation platforms will further expand accessibility to scientists with vertical takeoff and landing capabilities.
Germplasm lines with resistance to the sugarbeet root maggot (SBRM) have been developed and released to the public, providing a means to generate hybrids with resistance against the most devastating insect pest of sugarbeet in North America. Effective use of this germplasm, however, requires knowledge of relative strengths of SBRM resistance between lines and knowledge of the diversity and genetic relationships between germplasm. Therefore, field studies comparing SBRM resistance of four released SBRM-resistant germplasm lines (F1015, F1016, F1024 and F1043), a SBRM-resistant parent (PI 179180) and an unreleased SBRM-resistant population (F1055) were performed, and genetic analysis of the diversity and relationships between SBRM-resistant germplasm and their available parents was conducted using simple sequence repeat (SSR) markers. Under natural SBRM infestations, resistant germplasm exhibited significantly less SBRM damage than a susceptible control, with similar, high levels of resistance in F1016, F1024, F1043, F1055 and PI 179180 and lower resistance in F1015. SSR analysis revealed genetic similarities between F1016, F1024 and F1055, while F1015 and F1043 were genetically distinct from these lines. Among resistant genotypes, F1015 and F1043 exhibited greatest and least within-line genetic diversity, indicating greater and lesser inbreeding for F1043 and F1015, respectively. Similarities in damage ratings and genetics for F1016, F1024 and F1055 indicate that these lines are likely to be equally effective at introducing SBRM resistance into elite populations and in combining ability. In contrast, F1043, with its unique parentage and genetic dissimilarity from other resistant lines, provides a genetically distinct, but similarly effective, source of SBRM resistance.
Glioblastoma (GBM) is one of the most aggressive types of cancer which currently does not have a cure. Its invasive nature and heterogeneity makes its complete surgical removal impossible. Hence, a targeted treatment is critically needed to effectively eradicate this cancer. In this work, the authors report the synthesis of hollow TiO2 nanospheres (HTiO2NS) and their functionalization with folic acid (FA) and zinc (II) tetranitrophthalocyanine (ZnPc) to achieve cell selectivity and light absorption in the visible range. In vitro cytotoxicity of the functionalized HTiO2NS against M059K cell line (Human GBM cancer cells) was tested. In vitro generation of reactive oxygen species by HTiO2NS–FA–ZnPc nanostructures under UV irradiation was detected by fluorescence probing. To identify HTiO2NS–FA–ZnPc cell localization, the nanoparticles were labeled with fluorescein isothiocyanate dye and visualized by fluorescence microscopy. Results illustrate that HTiO2NS–FA–ZnPc nanostructures have the potential to be used for targeted photodynamic therapy for the treatment of GBM cancer.
Alterations of the gut microbiome have been associated with obesity and metabolic disorders. The gut microbiota can be influenced by the intake of dietary fibres with prebiotic properties, such as inulin-type fructans. This study tested the hypothesis that obese individuals subjected for 12 weeks to a inulin-enriched versus inulin-poor diet have differential faecal fermentation patterns. The fermentation of cellulose and inulin hydrolysates, of six different inulin-rich and inulin-poor vegetables of both groups was analysed in vitro on faecal inocula. The results showed that the microbiota from obese patients who received fructan-rich diet for three weeks produce more gas and total short-chain fatty acid (SCFA) compared to the microbiota taken of the same individuals before the treatment. Obese individuals fed with a low-fructan diet produce less gas and less SCFA compared to the treated group. This study highlighted profound changes in microbiota fermentation capacity obtained by prebiotic intervention in obese individuals, which favors the production of specific bioactive metabolites.
Parasites inflict many costs on their hosts. Understanding host–parasite relationship eco-evolutionary dynamics needs appreciation of how parasites affect individual fitness, survival and reproductive potential, and how they combine to influence population demography, dynamics and viability; also, how these processes drive microevolutionary processes that define natural and sexual selection. We synthesise work on the relationship between the red grouse and its main parasite, a gastrointestinal nematode. At individual level, we show how parasites impose a physiological cost, measured by immunosuppression and increased oxidative stress, and how their impact varies depending on contexts. We describe how parasite infection constrains expression of sexually selected traits and summarise how relationships between parasite, host and environment shape host population demography and dynamics. Genetic analyses in red grouse suggest nematode burden is moderately heritable, underpinned by a potentially large array of genes involved in the immune system, energy balance and broader homeostatic processes. There is no clear association between allele frequencies among populations and differences in nematode burdens. Possibly, beneficial alleles for parasite resistance cannot spread through the population due to the strong diversifying e?ects of gene ?ow and genetic drift.
The molybdenum disulfide (MoS2) and indium tin oxide (ITO) interface were studied by atom probe tomography (APT). Raman spectroscopy, scanning electron microscopy, and grazing-incidence x-ray diffraction measurements were performed as complementary characterization. Results confirm that nanowires plated shape with the 〈110〉-orientation are aligned perpendicular to the ITO film with principal reflections at (002), (100), (101), (201), and Raman spectroscopy vibrational modes at E12g at 378 cm−1 and A1g at 407 cm−1 correspond to 2H-MoS2. APT reveals MoS+2, MoS+3 as predominant evaporated molecular ions on the sample, indicating no significant diffusion/segregation of Mo or S species within the ITO layer.
Although common beans (Phaseolus vulgaris L.) are consumed worldwide, studies on the metabolic fate of phenolic compounds from common beans are still very scarce. The present work aimed to study the bioavailability of phenolic compounds in human plasma and urine, after acute consumption of a single meal of cooked common beans. Blood and urine of seven volunteers were collected before (0 h) and at different time points (1, 2, 4, 6 and 8 h, for plasma and 0-2, 2-4, 4-6, 6-8, 8-24 h for urine) after beans’ intake. UPLC-Q-TOF-MS was used for quantification. After beans’ intake (405 ± 3 g), containing 457 mg of phenolic compounds (expressed as gallic acid equivalents), there was a significant increase (p < 0.05) in the plasma concentration of 6 metabolites, and in the urinary excretion of 11 metabolites. After 1 h post-consumption, metabolites, such as kaempferol-3-O-glucuronide, showed a significant increase in plasma concentration, suggesting kaempferol’s glucuronidation in the upper gastrointestinal tract. More than 50% of the total amount of metabolites, such as 4-methylcatechol-O-sulfate and dihydrocaffeic acid-3-O-sulfate, were excreted after 8 h post-consumption, indicating colonic bacterial metabolism of the phenolic compounds. Throughout PLS-DA models the classification of biological samples, collected from the different volunteers, clearly showed clusters of metabolites, which contributed to extend the list of compounds related to cooked common beans’ human intake at different time points and showed the human inter-individual variability in plasma concentration, as well as, in the amount of urinary excreted metabolites, after cooked common beans’ intake.
The authors have shown recently that the neurite extension by neuronal PC12 cells is greatly impacted by aerogel topography. Indeed, the average neurite length of PC-12 cells grown on aerogels is greater than that in cells cultured on control substrates. Here, the authors report on the first experimental study focused on the design and development of a plasmonic photo-patterning technique for collagen-coated mesoporous aerogel biomaterials. Herein, the authors have produced specific patterns on silica aerogels by performing precise plasmonic photo-patterning on liquid crystal-coated aerogels. The authors report the methodology employed to create a collagen–liquid crystal gel mixture imprinted with precise plasmonic photo-patterns. PC12 cells plated on these patterns did attach and survive and followed the spatial cues of the pattern to align themselves in a similar pattern.
Tibraca limbativentris (Hemiptera: Pentatomidae) is a major pest in Neotropical rice agroecosystems. In autumn–winter, this pest takes refuge in rice stubble and in native vegetation, which allows it to re-colonize the crop during the rice growing season. However, it is still unknown whether this vegetation is a pest sink or is actually a natural trap that contributes to pest population biocontrol. Here we present information on the insect's alternative host plants, a preliminary outline of the relationship between plant phylogeny and insect abundance, and the impact that winter natural enemies have in pest population. Also, we include a proposed methodology for pest density analysis in winter hosts. Our results show significant differences in the abundance/density that T. limbativentris reaches in the 12 host plant species present in our study areas, with a plant-use pattern significantly related to the phylogenetic clade of Poales. Stink bug winter populations mainly comprised diapause adults, and 40% of insect digestive tracts had content. Survival of T. limbativentris was 56.92% in winter hosts. About mortality, 10% was due to undetermined causes and 33.08% due to entomopathogenic fungi, showing a natural regulation of the pest population. Our results suggest that native vegetation impacts winter survival of T. limbativentris. Although these plants offer shelter, they offer a greater contribution to Integrated Pest Management: the natural regulation of winter pest populations through entomopathogenic attack. Further studies on T. limbativentris population dynamics and the preservation of native areas near rice fields will be required for the development of best control practices.
Within developmental psychology, pointing gestures have received a great deal of attention, while ostensive gestures have been overlooked in terms of their emergence and intentionality. In a longitudinal and micro-genetic study with six children at 9, 11, and 13 months of age, we codified gesture production of children within second-by-second data frames. We identified 480 instances of gestures and categorised whether they were of ostensive, ostensive–indexical, or indexical nature. We specified the communicative function of each gesture by analysing the object involved and their circumstances of production. Data analysis include frequencies, binomial tests, proportion comparisons, and repeated measures ANOVA. We identified a phatic function in other-directed gestures, as well as exploratory and private functions in self-directed gestures. This has important implications for child development since ostensive gestures are easier to produce and to understand than pointing. The consideration of objects would be essential for defining the communicative function of gestures.
The present research was aimed to study the degradation of 2-Chlorophenol through the use of bismuth molybdate (γ-Bi2MoO6) structures supported on graphene oxide (GO) which is intended to control the recombination of charge carriers. γ-Bi2MoO6/GO systems were doped with nitrogen via chemical reaction, to reduce their energy gap, improving their photocatalytic activity. Structural and physicochemical characterization of the resulting catalysts were performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and UV-Vis. The obtained compounds show good photo catalytic performance when using visible energy to degrade 2-Chlorophenol, obtaining 80% of degradation in 65 min.
Different nanostructures such as: CuOH nanorods, CuO nanosheets and Cu2O nanograins were obtained by anodization approach at room temperature during times from 10 to 40 minutes. By scanning electron microscopy technique, it was found that Cu2O nanograins were formed at 10 minutes, CuO nanosheets vertically oriented on nanograins were observed at 20 and 30 minutes, and from 20 minutes CuOH nanorods with low vertical orientation on nanosheets were formed, coexisting the three types of nanostructures at the same system. In samples without thermal treatment were observed that Raman spectra of nanograins have a typical signal at 218 cm-1 associated to Cu2O, Raman spectra of nanosheets have signals at 287 and 630 cm-1 associated to CuO and Raman spectra of nanorods, it was observed that Raman spectrum is dominated by an intense signal associated to CuOH located around 488cm-1. In addition, after 3 hours of thermal treatment at 300 °C, the morphology was conserved, and the hydrogen-related compound decreased. Raman spectra of nanorods only presented a signal at 287 cm-1 associated to CuO whereas in nanosheets three peaks at 150, 218, 304 cm-1 associated to the Cu2O were observed.