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This paper explores attitudes and willingness to pay (WTP) for Norwegian salmon, Iranian rainbow trout, and Iranian narrow-barred Spanish mackerel among Iranian consumers. An interval regression model found that consumption frequency and product attributes affected WTP. Salmon was ranked highest on taste, nutrition, and convenience but lowest on price. The average estimated WTP for salmon was US $14.82, which is higher than for the other species but below the market price. The main challenges for salmon exporters will be to reduce the curren t high price and to differentiate salmon further in the market. [ABSTRACT FROM AUTHOR]

Discusses a study which systematically investigated the emission life of small Ba-impregnated thermionic cathodes suitable for use in television tubes. Information on the covering of cathodes; Cause of the early gradual decrease in emission at high cathode temperatures; Area where a linear relationship is found to exist.

In this work, we tried to combine the advantages of microemulsion and emulsion synthesis to obtain stable concentrated organosols of Ag nanoparticles, promising liquid-phase materials. Starting reagents were successively introduced into a micellar solution of sodium bis-(2-ethylhexyl)sulfosuccinate (AOT) in n-decane in the dynamic reverse emulsion mode. During the contact of the phases, Ag+ passes into micelles and Na+ passes into emulsion microdroplets through the cation exchange AOTNaOrg + AgNO3Aq = AOTAgOrg + NaNO3Aq. High concentrations of NaNO3 and hydrazine in the microdroplets favor an osmotic outflow of water from the micelles, which reduces their polar cavities to ~2 nm. As a result, silver ions are contained in the micelles, and the reducing agent is present mostly in emulsion microdroplets. The reagents interact in the polar cavities of micelles to form ~7 nm Ag nanoparticles. The produced nanoparticles are positively charged, which permitted their electrophoretic concentration to obtain liquid concentrates (up to 30% Ag) and a solid Ag-AOT composite (up to 75% Ag). Their treatment at 250 °C leads to the formation of conductive films (180 mOhm per square). The developed technique makes it possible to increase the productivity of the process by ~30 times and opens up new avenues of practical application for the well-studied microemulsion synthesis. [ABSTRACT FROM AUTHOR]

Chitosan is used in agriculture for its antifungal effect, lengthens the life of fruits and vegetables, it stimulates the growth of crops. Due to the need to increase crop yields in rice (Oryza sativa L.) this work was carried out with the objective of evaluating different times and forms of application of QuitoMax® in the final plant height and yield components in cultivar ̏ INCA LP 5 Ì‹. This treatment was performed to the seed at a concentration of 1 g L -1 and foliar spray at a dose of 360 mg L -1 at two ages at 25 and 60 days after germination (dag). Statistical software STATGRAPHICS version 4.1 was used in the Windows environment to analyze the results. The best response of the cultivar was obtained when treating the seed and when they received the two foliar applications of QuitoMax [ABSTRACT FROM AUTHOR]

Propagation characteristics of hydrogen-air deflagration need to be understood for an accurate risk assessment. Especially, flame propagation velocity is one of the most important factors. Propagation velocity of outwardly propagating flame has been estimated from burning velocity of a flat flame considering influence of thermal expansion at a flame front; however, this conventional method is not enough to estimate an actual propagation velocity because flame propagation is accelerated owing to cellular flame front caused by intrinsic instability in hydrogen-air deflagration. Therefore, it is important to understand the dynamic propagation characteristics of hydrogen-air deflagration. We performed explosion tests in a closed chamber which has 300 mm diameter windows and observed flame propagation phenomena by using Schlieren photography. In the explosion experiments, hydrogen-air mixtures were ignited at atmospheric pressure and room temperature and in the range of equivalence ratio from 0.2 to 1.0. Analyzing the obtained Schlieren images, flame radius and flame propagation velocity were measured. As the result, cellular flame fronts formed and flame propagations of hydrogen–air mixture were accelerated at the all equivalence ratios. In the case of equivalent ratio φ = 0.2, a flame floated up and could not propagate downward because the influence of buoyancy exceeded a laminar burning velocity. Based upon these propagation characteristics, a favorable estimation method of flame propagation velocity including influence of flame acceleration was proposed. Moreover, the influence of intrinsic instability on propagation characteristics was elucidated. [ABSTRACT FROM AUTHOR]

Values and personality affect food choices, and values are associated with personality. Food values are values that have been developed specifically within a food context. Our primary objective was to investigate the associations between these food values and the Big Five personality traits. An online survey with a choice experiment on food values and questions about socioeconomic characteristics and personality traits were conducted in Norway and the US. A latent class logit model was used to segment respondents based on the relative importance they assigned to the different food values. Personality traits and socioeconomic characteristics were used to determine the probability of membership in each segment. A health, an altruistic, a rational, and a hedonistic segment were identified in both countries. In addition, Norwegian natural and welfare segments and US safety and indeterminate segments were identified. Several personality traits and socioeconomic characteristics were significant in defining the segments, and these traits and characteristics can potentially be used for marketing purposes of foods with sustainability-related attributes. Marketing activities can be targeted at segments who emphasize sustainability-related aspects of food consumption such as environmental impact, fairness, and animal welfare. • Personality traits were associated with food values. • Openness, agreeableness, and extraversion were positively associated with altruistic values. • Extraversion was positively associated with the hedonistic values in Norway. • Similar health, altruistic, rational, and hedonistic segments exist in both countries. • Promotional activities may be tailored to approach different personalities. [ABSTRACT FROM AUTHOR]

Background Dementia is generally considered an irreversible process of cognitive decline that can be caused by different neurodegenerative diseases. However, in some cases, dementia is caused by a non-neurodegenerative disease, such as an affective disorder. In these cases, the dementia can be reversible. Nevertheless, cognitive symptoms due to an affective disorder are often difficult to distinguish from a depressed mood due to a neurodegenerative disease. Especially in elderly patients with a history of affective disorder, a potentially reversible cause can be missed. Case presentation We describe a 60-year-old white woman with bipolar disorder, depressive symptoms, a movement disorder and severe cognitive impairment, in whom a neurodegenerative disease was seriously considered. She was referred to our clinic for further investigation because initial treatment of the depressive episode with antidepressants, mood stabilizers and electroconvulsive therapy (ECT) had not been successful. However, despite extensive evaluation, we could not find evidence for a neurodegenerative disease and the patient mostly recovered after discontinuation of different psychotropic medications and treatment with nortriptyline. Conclusions Our case shows that improvement of severe cognitive impairment in individual cases is possible. In our opinion, this underlines the necessity of a careful re-evaluation of the patient's symptoms at presentation and the course of the disease as well as a critical review of the prescribed medications. [ABSTRACT FROM AUTHOR]

Population migration has played an important role in human evolutionary history and in the patterning of human genetic variation. A deeper and empirically-based understanding of human migration dynamics is needed in order to interpret genetic and archaeological evidence and to accurately reconstruct the prehistoric processes that comprise human evolutionary history. Current empirical estimates of migration include either short time frames (i.e. within one generation) or partial knowledge about migration, such as proportion of migrants or distance of migration. An analysis of migration that includes both proportion of migrants and distance, and direction over multiple generations would better inform prehistoric reconstructions. To evaluate human migration, we use GPS coordinates from the place of residence of the Yemeni individuals sampled in our study, their birthplaces and their parents' and grandparents' birthplaces to calculate the proportion of migrants, as well as the distance and direction of migration events between each generation. We test for differences in these values between the generations and identify factors that influence the probability of migration. Our results show that the proportion and distance of migration between females and males is similar within generations. In contrast, the proportion and distance of migration is significantly lower in the grandparents' generation, most likely reflecting the decreasing effect of technology. Based on our results, we calculate the proportion of migration events (0.102) and mean and median distances of migration (96 km and 26 km) for the grandparent's generation to represent early times in human evolution. These estimates can serve to set parameter values of demographic models in model-based methods of prehistoric reconstruction, such as approximate Bayesian computation. Our study provides the first empirically-based estimates of human migration over multiple generations in a developing country and these estimates are intended to enable more precise reconstruction of the demographic processes that characterized human evolution. [ABSTRACT FROM AUTHOR]

Supramolecular polymers can be random and entangled coils with the mechanical properties of plastics and elastomers, but with great capacity for processability, recycling, and self-heating due to their reversible monomer-to-polymer transitions. At the other extreme, supramolecular polymers can be formed by self-assembly among designed subunits to yield shape-persistent and highly ordered filaments. The use of strong and directional interactions among molecular subunits can achieve not only rich dynamic behavior but also high degrees of internal order that are not known in ordinary polymers. They can resemble, for example, the ordered and dynamic one-dimensional supramolecular assemblies of the cell cytoskeleton and possess useful biological and electronic functions. [ABSTRACT FROM AUTHOR]

Abstract: We perform a molecular dynamics simulation for CO2 +ketone mixtures to study the molecular motility and elucidate how CO2 molecules are dissolved in a mixture. The self-diffusion coefficients increase with increasing CO2 mole fraction and decreased with increasing molecular weight. These results mean that the mobility of molecules depends on the molecular size. To study molecular aggregation around CO2 molecules, radial distribution functions (RDFs) and the distance from neighboring molecules to CO2 molecules were calculated. The RDFs indicate that the CO2 molecule exists near the carbonyl oxygen atom. Because of the distance of the neighboring molecule from the CO2 molecule, the CO2 molecule is less likely to exist around a branched alkyl ketone than a normal alkyl ketone. [ABSTRACT FROM AUTHOR]

Studies were carried out as part of the Agriculture Biotechnology program, to prepare and characterize chemically and biologically different chitosans obtained from Cuban lobster chitin. Chitosan polymers were subjected to acid and enzymatic hydrolysis by using low-cost commercial enzymatic preparations, and the resulting oligosaccharide mixtures were further characterized. Their potential antimicrobial activities were also evaluated versus fungi and oomycetes, also testing their ability to induce defensive and protective responses in tobacco and rice plants against two economically relevant pests, Phytophthora nicotianae and Pyricularia grisea, respectively. With the aid of international collaboration, different oligochitosans mixtures were compared for activating defensive responses in suspension cultures of Arabidopsis thaliana cells. These results bring knowledge on the physical-chemical properties of the chitosans obtained, such as molar mass and acetylation grade, and their influence on activating defensive responses, the inhibition of growth in pathogens and the induction of resistance in tobacco and rice plants. Some of these chitosan derivatives were selected as possible active components to protect both type of cultivars, being applied at field-scale to evaluate their effects for the main natural pathogens and bringing very promising results. This research allowed us to establish a methodology for preparing oligochitosans, and results shown inhere were part of BSc, MSc and PhD theses, and were also published in more than 20 scientific papers and presented in more than 40 scientific conferences. [ABSTRACT FROM AUTHOR]

Chitin is a biodegradable polymer widely spread in nature. It is mainly obtained form crustacean shells. Chitin and its derivatives have shown to be effective in controlling plagues and plants diseases. Their mechanism of action is strongly linked to their chemical structures. These mechanisms can result from the direct action on the pathogen or can be a consequence of its capacity to induce defensive mechanisms on plants. In any case, the effect is their protection against various vegetable diseases, before and after harvest. The addition of chitin and its derivatives to the soil favours the growth and activity of many chitinolytic organisms that constitute biological controls and are natural enemies of many agents responsible for vegetable plagues and diseases, generating a synergistic effect. On the other side, these biopolymers also favour the growth and development of beneficial microorganisms that establish synergistic relationships with plants, such a as mycorrhizas or Rhizobium species. On top of that, increasing the microbial population and activity in the soil improves the properties of nutrients and their availability. As growth regulators, it has been established that these biopolymers accelerate seeds germination, the ability of plants to grow as well as the agricultural yield. It is concluded that chitin and its derivatives have great potential for applications in agriculture. It is foreseen that in the future these biopolymers will be used in greater extension, mainly for substituting actual chemical pesticides or as growth regulators. [ABSTRACT FROM AUTHOR]

La quitina es un polímero biodegradable muy abundante en la naturaleza, que se obtiene fundamentalmente del exoesqueleto de los crustáceos, y del que mucho se ha escrito por sus potencialidades de aplicación en la agricultura. Ella y sus derivados son efectivos en el control de enfermedades y plagas vegetales. Sus mecanismos de acción están vinculados a su estructura química. Pueden actuar sobre el organismo patógeno, o inducir mecanismos defensivos en las plantas, contra varias enfermedades vegetales antes y después de la cosecha. La adición de quitina y sus derivados al suelo, favorece el crecimiento y la actividad de muchos organismos quitinolíticos, por un efecto sinérgico. Estos constituyen controles biológicos y enemigos naturales de muchos agentes causales de enfermedades y plagas vegetales. Además, favorecen el crecimiento y desarrollo de microorganismos beneficiosos que establecen relaciones simbióticas con las plantas, tales como las micorrizas o especies del género Rhizobium. A su vez, incrementan la población y la actividad microbiana en el suelo, lo que mejora la disposición de nutrientes y sus propiedades. Como reguladores del crecimiento, aceleran la germinación de las semillas, el vigor de las plantas, y el rendimiento agrícola. Por tanto, por su gran potencial de aplicación en la agricultura, se augura que se utilizarán con una mayor extensión, principalmente como sustitutos de los actuales plaguicidas químicos o como reguladores del crecimiento de las plantas. [ABSTRACT FROM AUTHOR]

We isolated and characterized 12 microsatellite loci from the hawksbill sea turtle ( Eretmochelys imbricata). The loci exhibited a variable number of alleles that ranged from three to 14 with an average observed heterozygosity of 0.70 (SD 0.18) across 40 hawksbill turtles from the Caribbean. The polymorphism exhibited individually and in combination makes them suitable for fine-scale genetic studies. In particular, the low probability of identity and high paternity exclusion of these markers makes them highly useful for parentage and relatedness studies. These new markers greatly increase the power of genetic studies directed towards the conservation of this endangered species. [ABSTRACT FROM AUTHOR]

The stimulation of defense mechanisms in plants through using of bioactive products is one of the most ecological and dynamic ways to defend them from pathogen attack. Among elicitors promoting this induction is hydrolisate of chitosan, which was obtained in the Department of Crop Physiology and Biochemistry from the National Institute of Agricultural Sciences (INCA). This work determined the effect of a hydrolisate of chitosan applied to seed on the stimulation of some enzymes related with pathogenesis, such as PAL, glucanase, chitinase and chitosanase in rice plants (var. J-104). It was observed that with the application of this compound, there was an induction of the activity of different enzymes. The highest values of the activity of enzymes PAL and β-1,3 glucanases were observed at the concentration of 500 mg.L-1 whereas in chitinase and chitosanase at the concentration of 100 mg.L-1. It was demonstrated that at lower concentrations than 1 000 mg.L-1 a higher estimulation of the activity of evaluated enzymes is obtained. [ABSTRACT FROM AUTHOR]

The finite element method is employed to analyze photoacoustic cavitation and heat transfer occurring when modest temperature jumps (T-jumps) are induced by a laser in D[sub 2] O solution, which may contain a small concentration of a protein or peptide sample. Cavitation can be initiated through a photoacoustic mechanism at intensities well below optical breakdown thresholds. Cavitation probability is related to test medium properties, initial temperature, T-jump magnitude and test region geometry. Parameters affecting thermal conduction losses are also examined because such losses limit the useful duration of the T-jump induced in protein folding experiments. From this study, guidelines are offered for reducing the occurrence of cavitation and extending the useful duration of the T-jump. [ABSTRACT FROM AUTHOR]

Antimicrobial activity of chitosan has been previously demonstrated on some fungi species. In this work, the direct effect of a low molecular weight chitosan (121.6 kDa) on the morphology of Bipolaris oryzae was studied by light and scanning electron microscopy techniques. Changes in the hyphae and germ tubes were observed. Moreover, structural and morphological changes during the apical growth phase of the fungus were detected by scanning electron microscopy at 3 g/L chitosan. B. oryzae hyphae malformations were detected, with shortening and thickening of hyphae and spore germ tubes shortening and swelling, together with hyphae agglomerations, all these changes affecting the fungus' multiplication and spreading capacity. These results support the possible use of the assayed chitosan in pest control strategies against B. oryzae in rice crops. [ABSTRACT FROM AUTHOR]

• Personality traits influenced preferences for GM soybean oil, GM-fed and GM salmon. • Conscientiousness reduced aversion towards GM-fed salmon and GM salmon. • Agreeableness increased aversion against GM-fed salmon and GM salmon. • Agreeableness and conscientiousness were correlated with knowledge. • Respondents were less averse of GM-fed salmon than GM soybean oil and GM salmon. Several studies have investigated the associations between personality traits and consumer behavior, but little attention has been paid to the role of personality traits in the acceptance of genetically modified (GM) food products or knowledge concerning the application of GM technologies. We used a large Norwegian survey to investigate the associations between personality traits, knowledge about GM use in agriculture, attitudes, and willingness to pay (WTP) to avoid GM foods. Using a random effect interval regression model, we found premiums between 19% and 23% to avoid GM soybean oil, GM-fed salmon, and GM salmon. Neuroticism was associated with increased acceptance of GM soybean oil. Conscientiousness was associated with increased acceptance of GM-fed and GM salmon, and agreeableness was associated with increased aversion against these products. Conscientiousness and agreeableness were also associated with knowledge. Agreeable respondents were less likely to think that genetic modification was applied in Norwegian agriculture, and conscientious respondents were more likely to wrongly think so. Attitudes towards naturalness of foods were strongly correlated with increased WTP to avoid GM foods. Current policy restrictions concerning the use of GM technologies are likely to affect the perceived safety of GM foods. Information and more liberal regulations may change attitudes towards GM foods and reduce the resistance against GM technologies over time. [ABSTRACT FROM AUTHOR]

Nickel–cobalt sulfide is a promising material for supercapacitor positive electrodes due to its high theoretical capacitance. Herein, the electrochemical properties of nickel–cobalt sulfide nanostructures synthesized via a two‐stage hydrothermal method are investigated and the synthesis conditions to achieve high mass loading while maintaining high specific capacitance are determined. The nanostructural morphology and effective mass loading of the electrodes (≈10 mg cm−2) enable the achievement of a high specific capacitance value of 8.1 F cm−2 at a current density of 5 mA cm−2. A hybrid capacitor is made using optimized nickel–cobalt sulfide electrodes as the positive electrode and activated carbon as the negative electrode. The device exhibits a maximum operation potential window of 1.75 V and an energy density of 51.2 Wh kg−1 at a power density of 262.5 W kg−1. Electrochemical measurements demonstrate that the device maintains a capacitance retention rate of 95% after 10 000 charge–discharge cycles within a working voltage of 1.8 V. High electrochemical performances compared with others devices‐based water electrolytes make it promising for the energy storage device. [ABSTRACT FROM AUTHOR]

Recently, heterostructured photocatalysts have gained significant attention in the field of photocatalysis due to their superior properties compared to single photocatalysts. One of the key advantages of heterostructured photocatalysts is their ability to enhance charge separation and broaden the absorption spectrum, thereby improving photocatalytic efficiency. Zinc oxide is a widely used n-type semiconductor with a proper photoelectrochemical activity. In this study, zinc oxide nanorod arrays were synthesized, and then the surfaces of ZnO nanorods were modified with the p-type semiconductor Co3O4 to create a p–n junction heterostructure. A significant increase in the photocurrent for the ZnO/Co3O4 composite, of 4.3 times, was found compared to pure ZnO. The dependence of the photocurrent on the morphology of the ZnO/Co3O4 composite allows for optimization of the morphology of the ZnO nanorod array to achieve improved photoelectrochemical performance. The results showed that the ZnO/Co3O4 heterostructure exhibited a photocurrent density of 3.46 mA/cm2, while bare ZnO demonstrated a photocurrent density of 0.8 mA/cm2 at 1.23 V. The results of this study provide a better understanding of the mechanism of charge separation and transfer in the heterostructural ZnO/Co3O4 photocatalytic system. Furthermore, the results will be useful for the design and optimization of photocatalytic systems for water splitting and other applications. [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives Anatomically, modern humans are thought to have migrated out of Africa ∼60,000 years ago in the first successful global dispersal. This initial migration may have passed through Yemen, a region that has experienced multiple migrations events with Africa and Eurasia throughout human history. We use Bayesian phylogenetics to determine how ancient and recent migrations have shaped Yemeni mitogenomic variation. Materials and Methods We sequenced 113 mitogenomes from multiple Yemeni regions with a focus on haplogroups M, N, and L3(xM,N) as these groups have the oldest evolutionary history outside of Africa. We performed Bayesian evolutionary analyses to generate time-measured phylogenies calibrated by Neanderthal and Denisovan mitogenomes in order to determine the age of Yemeni-specific clades. Results As defined by Yemeni monophyly, Yemeni in situ evolution is limited to the Holocene or latest Pleistocene (ages of clades in subhaplogroups L3b1a1a, L3h2, L3x1, M1a1f, M1a5, N1a1a3, and N1a3 range from 2 to 14 kya) and is often situated within broader Horn of Africa/southern Arabia in situ evolution (L3h2, L3x1, M1a1f, M1a5, and N1a1a3 ages range from 7 to 29 kya). Five subhaplogroups show no monophyly and are candidates for Holocene migration into Yemen (L0a2a2a, L3d1a1a, L3i2, M1a1b, and N1b1a). Discussion Yemeni mitogenomes are largely the product of Holocene migration, and subsequent in situ evolution, from Africa and western Eurasia. However, we hypothesize that recent population movements may obscure the genetic signature of more ancient migrations. Additional research, e.g., analyses of Yemeni nuclear genetic data, is needed to better reconstruct the complex population and migration histories associated with Out of Africa. Am J Phys Anthropol 159:382-393, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

African Americans are 40% more likely to be afflicted with hypertension than are non-Hispanic, white Americans, resulting in a 30% higher instance of mortality due to cardiovascular disease. There is debate about the relative contributions of genetic and sociocultural risk factors to the racial disparity in hypertension. We assayed three Alu insertion polymorphisms located in the ACE (angiotensin 1 converting enzyme), PLAT (plasminogen activator, tissue), and WNK1 (lysine deficient protein kinase 1) genes. We also estimated West African genetic ancestry and developed novel measures of perceived discrimination to create a biocultural model of blood pressure among African American adults in Tallahassee, Florida (n = 158). When tested separately, the ACE Alu noninsertion allele was significantly associated with higher systolic and diastolic blood pressure. In multiple regression analyses, West African genetic ancestry was not associated with blood pressure and reduced the strength of all blood pressure models tested. A gene × environment interaction was identified between the ACE Alu genotype and a new measure of unfair treatment that includes experiences by individuals close to the study participant. Inclusion of the WNK1 Alu genotype further improved this model of blood pressure variation. Our results suggest an association of the ACE and WNK1 genotypes with blood pressure that is consistent with their proposed gene functions. Measures of perceived unfair treatment of others show a threshold effect, with increased blood pressure occurring at higher values. The interaction between the ACE genotype and unfair treatment highlights the benefits of including both genetic and cultural data to investigate complex disease. [ABSTRACT FROM AUTHOR]

H and O NMR relaxation times, T(H) and T(O), and H NMR chemical shifts, δ(H), in CO-saturated CDOD and CDOD solutions were measured at 313.2 K over the pressure range up to ~6 MPa. The rotational correlation times, τ, of the CD and OD axes within CDOD and CDOD molecules and the CO axis within the CO molecule were determined from T(H) and T(O), and the magnetic susceptibility-corrected chemical shifts, δ, were derived from δ(H). The differences in τ and δ observed between the two alcohol systems: τ and δ of OD in CDOD, decreased rapidly with increasing CO concentration, while those of OD in CDOD remained almost unchanged at mole fractions of CO, $$ x_{\text CO_{2}} $$ , lower than ~0.25 and then slightly decreased at higher $$ x_{\text CO_{2}} $$ . The hydrogen bonding structure in CDOD was found to be gradually broken down by CO dissolution. On the other hand, in CDOD, it has been revealed that the hydrogen bonding structure can persist at $$ x_{\text CO_{2}} $$ < ~0.25 but then collapses at higher $$ x_{\text CO_{2}} $$ . [ABSTRACT FROM AUTHOR]

A new method of gold concentration with a total enrichment factor of ∼104 has been developed. The method includes a liquid-liquid extraction of [image omitted] by reverse micelles; reduction of gold (III) to Au nanoparticles (with hydrazine monohydrate as a reducing agent) in the extracts and an electrophoretic concentration of the particles in a cell with parallel-plane electrodes. With increasing sodium sulfate concentration in the feed there was a decrease of water content for ordinary micelles and an increase of gold extraction. At a constant acid-salt background (3 mol/L HCl + 3.5 mol/L Na2SO4) concentration, AOT introduction into micelles led to a decrease in extraction. The obtained regularities are consistent with a hydrate-solvate mechanism. The electrophoretic mobility of gold nanoparticles in extracts has been determined. When AOT was introduced into the extracts after the stage of reduction the electrophoretic mobility of nanoparticles was considerably increased (from -1.8 × 10-11 to 1.8 × 10-10 m2/(V × s)) which made possible an additional stage of electrophoretic concentration with an enrichment factor of ∼1.5 × 103. [ABSTRACT FROM AUTHOR]

In «Los Palacios» Rice Research Station, belonging to the National Institute of Agricultural Sciences (INCA), the effect of some chitin derivatives (chitosan and its hydrolysate) and its copper combinations on in vitro growth and sporulation of Pyricularia grisea fungus was studied. This fungus is the causal agent of Blast, the most important disease of rice crop in the world, whose conidia are the initial inoculum of such disease. One 8-mm-diameter mycelial disk was submerged for 15 minutes in each treatment and three, five and seven days later, the colony diameter was measured. Afterwards, conidial number was counted by a counting chamber and the colony sporulation distribution was observed. Results showed no significative effect of chitosan and its hydrolysate at 100 mg.L-1 concentration nor their combination with copper on Pyricularia grisea mycelial growth; however, they inhibited pathogen sporulation between 70 and 85 %; the few sporulation of chitosans was dispersed to colony periphery, whereas in the control, it was grouped in the center. These results permit to lead the possibility of using chitosans at low concentrations in the initial disease inoculum reduction in the field. [ABSTRACT FROM AUTHOR]

The mechanical relaxation in binary, ternary, quaternary, and quitary bulk metallic glasses with widely different glass-forming ability, or the critical cooling rate, has been studied. A single-roller melt-spinning apparatus was used for preparing thin specimens. The internal friction Q−1 and the oscillation frequency f of the specimens were measured using an inverted torsion pendulum with the free decay method. The measurements were performed from room temperature, through the glass transition temperature Tg, up to the crystallization temperature Tx. As the temperature is increased, the background Q−1 increases, and peaks can usually be seen near Tg and Tx. The shear modulus, which is proportional to f2, is changed near the Q−1 peak. The experimental data are presented and overall features of the results are discussed. [Copyright &y& Elsevier]

The internal friction (IF) of Johnson alloy (Zr–Ti–Cu–Ni–Be) glass prepared by a single-roller melt-spinning method was measured using an inverted torsion pendulum with the free decay method. The measurements were performed from room temperature, through the glass transition temperature Tg, up to the crystallization temperature Tx. The effect of isothermal annealing at a temperature about 20 K below Tg was studied. By the annealing the unstable glassy state and the metastable supercooled state were transferred to more stable ones (stabilization). In a well-stabilized state, the background IF was flat at lower temperatures, increased rapidly at higher temperatures, and an IF peak appeared near Tx together with another peak at a lower temperature. No IF peak was observed near Tg. Qualitative discussions are presented for the experimental results, and possible use of the glass as a high damping material is briefly mentioned. [Copyright &y& Elsevier]

Describes a laser device which generates wavelength-hopping sequences useful for optical communication. How the wavelength hopping sequences are generated; Description of the methods for data transmission using periodic and chaotic hopping sequences.

A water management study was conducted in one irrigation sloping system, in order to know its effect on the electric conductivity of soil saturation extract and rice yield. It was performed at Cubanacán seed farm, pertaining to "Los Palacios" Rice Agroindustrial Complex, for three poorly rainy and three rainy seasons from 2000 to 2002. Results showed a significant crop yield reduction and increased electric conductivity of soil saturation extract when irrigation was applied on sloping terraces. Significant differences were recorded between the first two terraces and the last one. [ABSTRACT FROM AUTHOR]

We show that modulated near-infrared radiation can generate terahertz plasma oscillations in the channel of a high-electron mobility transistor. This effect is associated with a temporarily periodic injection of the electrons photoexcited by modulated near-infrared radiation into the transistor channel. The excitation of the plasma oscillations has the resonant character. It results in the pertinent excitation of the electric current in the external circuit that can be used for generation of terahertz electromagnetic radiation. [ABSTRACT FROM AUTHOR]

We study the performance of a lateral p -- n junction quantum-well edge-emitting laser-transistor with an extra gate contact. The incorporation of the gate contact provides an opportunity to control the threshold current and output optical power by the gate voltage. The application of negative gate voltages can lead to a substantial decrease in the threshold current. This is due to the confinement of the electrons injected into the p-type portion of the quantum well serving as the active region. Using the developed device model, we calculate the laser-transistor threshold and output characteristics. We also estimate the device cutoff modulation frequency associated with the gate recharging. [ABSTRACT FROM AUTHOR]

The drought causes negative effects on the productivity of the plants and constitutes a potential danger for the food sustainability of the population. One of the most difficult tasks for rice breeders is to increase tolerance to salinity and drought, in addition to achieving high and stable yields. In the genetic improvement program of this precious grain, different improvement methods are used, where biotechnological techniques have been used, using the in vitro anther culture to shorten the time for obtaining haploid lines, which will be subsequently evaluated in conditions of water deficit. For these reasons, this work was aimed to obtain double haploid lines through in vitro anther culture of F2 hybrid populations, and evaluate them under water deficit conditions. Crosses were made between five drought-resistant cultivars and six cultivars of good agronomic performance. Anthers of F2 plants were cultured in vitro to evaluate callus formation in three liquid media: N6m, NL and N6-1. Then, agronomic characters and tolerance to water deficit were evaluated in the first generation of isogenic lines obtained. Double haploid lines that combined drought resistance and good agronomic traits were evaluated under field conditions without watering, only with water passes as the plant required. The use of the in vitro anther culture technique showed the high dependence on genotype and culture medium. The highest values of callus formation were achieved in the NL culture medium. New double haploid lines resistant to water deficit and showing high agricultural yield were obtained. [ABSTRACT FROM AUTHOR]

The work was carried out in the biotechnology laboratory at the Scientific Technological Base Unit "Los Palacios" (UCTB), which belongs to the National Institute of Agricultural Sciences (INCA) in Los Palacios municipality, in province of Pinar del Río in the March to May period. One hundred (100) seeds of three rice cultivars obtained by different methods of improvement, INCA LP-10, J-104 and INCA LP-7, this last salinity tolerant control were selected and were germinated in petri dishes with paper of Filter and wetted with 15 mL the different saline concentrations of sodium chloride (NaCl) (4000, 7000 and 10000 ppm), distilled water was used as the control. The number of germinated seeds was evaluated at 7 days, determining the germination percentage and at 15 days the height of the seedlings, root length and accumulation of fresh and dry biomass were evaluated in 10 seedlings per replicate, being determined the index of Tolerance to salinity. Varietal differences were observed regarding the live response of the cultivars under study with saline concentrations, where the cultivar INCA LP-7 and INCA LP-10 showed the best tolerance indices for these abiotic stress conditions. [ABSTRACT FROM AUTHOR]

Studies of Native American genetic diversity and population history have been transformed over the last decade by important developments in anthropological genetics. During this time, researchers have adopted new DNA technologies and computational approaches for analyzing genomic data, and they have become increasingly sensitive to the views of research participants and communities. As new methods are applied to long-standing questions, and as more research is conducted in collaboration with indigenous communities, we are gaining new insights into the history and diversity of indigenous populations. This review discusses the recent methodological advances and genetic studies that have improved our understanding of Native American genomics and population histories. We synthesize current knowledge about Native American genomic variation and build a model of population history in the Americas. We also discuss the broader implications of this research for anthropology and related disciplines, and we highlight challenges and other considerations for future research. [ABSTRACT FROM AUTHOR]

Studies of Native American genetic diversity and population history have been transformed over the last decade by important developments in anthropological genetics. During this time, researchers have adopted new DNA technologies and computational approaches for analyzing genomic data, and they have become increasingly sensitive to the views of research participants and communities. As new methods are applied to long-standing questions, and as more research is conducted in collaboration with indigenous communities, we are gaining new insights into the history and diversity of indigenous populations. This review discusses the recent methodological advances and genetic studies that have improved our understanding of Native American genomics and population histories. We synthesize current knowledge about Native American genomic variation and build a model of population history in the Americas. We also discuss the broader implications of this research for anthropology and related disciplines, and we highlight challenges and other considerations for future research. [ABSTRACT FROM AUTHOR]

The work was made in the Plant Phytopathology Laboratory belonging to the Scientific and Technological Base Unit Base Los Palacios. The aims of this research was to evaluate the antifungal activity of four chitosan formulates Q (100, 500, 1000 mg.L-1) y chitosan and copper (QCu-100 mg.L-1) on the mycelial growth and in vitro sporulation rate of Pyricularia grisea Sacc fungus. Results showed that 1000 mg.L-1 chitosan and QCu-100 mg.L-1 had the greatest inhibitory effect on four day with 27 y 30 %, respectively. However fungal sporulation was inhibited in 100 % by el QCu, while Q 100 y Q 500 had inhibitory percentages between 80 y 96 % on center and peripheral zones respectively. In addition, Q-1000 mg.L-1 chitosan had not a noticeable effect on fungal sporulation. [ABSTRACT FROM AUTHOR]

To determine the antifungal activity of chitosan against Bipolaris oryzae, which is a pathogen with the highest incidence in the rice spotted grain disease and the causal agent of brown leaf spot, the in vitro effect of different concentrations (300, 500, 700 and 1000 mg/L) of K1 (INCA) and SIGMA chitosans on fungal mycelial growth was studied. The colony diameter was measured after 3, 4, 5, 6 and 7 days, and the inhibition percentage of fungal mycelial growth compared with the non-treated control was calculated. The fungicide effect of the product for the treatment that totally inhibited the fungus was determined. The results indicated that both products had an inhibitory effect on fungal growth at all evaluated concentrations. SIGMA chitosan showed a total inhibition at 1000 mg/L, besides its fungicide effect. [ABSTRACT FROM AUTHOR]

The in vitro effect of different concentrations (300, 500, 700 and 1000 mg/L) of K1 (INCA) and SIGMA chitosans on mycelial growth and sporulation of the rice grain pathogen fungus Fusarium subglutinans was studied. The colony diameter was measured after 3, 4, 5, 6 and 7 days, and the inhibition percentage of fungal mycelial growth compared with the non-treated control was determined. Conidia concentration was evaluated after 7 days. The fungicide effect of the product was determined for the treatments that totally inhibited the fungus. The results indicated that both products had an inhibitory effect on growth and sporulation at all evaluated concentrations. SIGMA chitosan showed a total inhibition at 1000 mg/L. Both substances had a fungistatic effect on F. subglutinans. [ABSTRACT FROM AUTHOR]

The effect of Q-63 chitosan active ingredient (100, 500 and 1000 mg/L) on the germination of Fusarium sp conidia, as well as its potentiality for protecting rice seeds inoculated with the pathogen was studied. The germination percentage of conidia treated with different concentrations of Q-63 was evaluated after 2, 5, 8, 11 and 14 hours, while the fungal infection percentage in seeds treated with Q-63 was determined after 6, 7, 8 and 9 days. The results showed that both 500 and 1000 mg/L concentrations inhibited conidia germination completely until 14 hours. However, the best protective effect on seeds (93.3 %) was obtained with the higher concentration at 9 days. [ABSTRACT FROM AUTHOR]

We fabricated quantum well (QW) microtubes by rolling up thin films containing QWs and measured their photoluminescence (PL) properties. Before fabricating microtubes, no PL signal is observed in the QW at all, because their band configuration is indirect, i.e., type-II. However, PL signal is detected in the QW microtubes. This result clearly indicates that the transition from type-II to type-I band configuration of QW microtubes is induced by uniaxial-strain effect. [Copyright &y& Elsevier]

We fabricated micro-tubes containing two GaAs/AlGaAs quantum wells (QWs) in a section of the tube layer, and studied the optical properties of the embedded QWs. A multilayer structure composed of GaAs and AlGaAs layers and a lattice-mismatched InGaAs layer was epitaxially grown on a GaAs substrate by MBE. This multilayer structure rolled up by the built-in strain when it was freed from the substrate. By measuring the photoluminescence peak shift of the QWs caused by the uniaxial strain, we were able to determine the radial profile of the strain within the micro-tube wall. [Copyright &y& Elsevier]

Proposes a communication system based on the synchronization of optical chaos in semiconductor lasers. How the synchronization of chaos is performed; Numerical and experimental results on synchronization of giga-hertz chaotic signals; Implication of bit-error rate on frequency detuning.

Carbon nanohorns (CNHs) are attractive for various applications, where a high specific surface area and long dispersion stability in water are important. In the present work, we study these parameters of CNHs prepared by arc evaporation of graphite depending on the conditions of the synthesis and subsequent oxidation in air. It is shown that the addition of toluene in the reactor during the arcing allows obtaining CNHs functionalized with −CHx groups. Heating of CNHs in air at 400 °C leads to substitution of −CHx groups for oxygen-containing groups. Moreover, the CNH endcaps are opened at 500 °C, and as a result, the specific surface area of CNHs increases 4 times. Aqueous suspensions with a concentration of oxidized CNHs of 100 µg/mL are stable for 8 months. [ABSTRACT FROM AUTHOR]

In "Los Palacios" Rice Research Station, an experiment was developed in the period between 1996 and 2001, in order to know the effect of ratoon over yield with a mid cycle rice variety. Results showed that the lower the ratoons were cut, compared with the control, the lower the yield reached compared to the first crop; a similar behavior presented leaf area index (IAF). The ratoon cycle was reduced with respect to the main crop in a period between 45 and 60 days. [ABSTRACT FROM AUTHOR]

We fabricated and experimentally investigated a nanostructure known as a quantum-well (QW) microtube, which is a fine tube with a micron- or nanometer-order diameter fabricated by rolling a semiconductor GaAs QW. Although the wall thickness is only 40 nm, the system retains the quantum properties of a QW, and photoluminescence from the QW subband can be clearly observed. Even though the QW width is sufficiently small to make the QW subband type-II band-aligned, a type-II to type-I transition caused by uniaxial strain in the microtube allows for optical emission. [ABSTRACT FROM AUTHOR]