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Stictococcus vayssierei is a major pest of root and tuber crops in central Africa. However, data on its ecology are lacking. Here we provide an updated estimate of its distribution with the aim of facilitating the sustainable control of its populations. Surveys conducted in nine countries encompassing 13 ecological regions around the Congo basin showed that African root and tuber scale was present in Cameroon, Central African Republic, Congo, Democratic Republic of Congo, Equatorial Guinea, Gabon and Uganda. It was not found on the sites surveyed in Chad and Nigeria. The pest occurred in the forest and the forest-savannah mosaic as well as in the savannah where it was never recorded before. However, prevalence was higher in the forest (43.1%) where cassava was the most infested crop, compared to the savannah (9.2%) where aroids (cocoyam and taro) were the most infested crops. In the forest habitat, the pest was prevalent in all but two ecological regions: the Congolian swamp forests and the Southern Congolian forest-savanna mosaic. In the savannah habitat, it was restricted to the moist savannah highlands and absent from dry savannahs. The scale was not observed below 277 m asl. Where present, the scale was frequently (87.1% of the sites) attended by the ant Anoplolepis tenella. High densities (>1000 scales per plant) were recorded along the Cameroon–Gabon border. Good regulatory measures within and between countries are required to control the exchange of plant materials and limit its spread. The study provides information for niche modeling and risk mapping.
Solid state batteries are an emerging alternative to traditional liquid electrolyte cells that provide potential for safe and high-energy density power sources. This report describes a self-forming, solid state battery based on the Li/I2 couple using an LiI-rich LiI(3-hydroxypropionitrile)2 electrolyte (LiI–LiI(HPN)2). As the negative and positive active materials are generated in situ, the solid electrolyte–current collector interfaces play a critical role in determining the electrochemical response of the battery. Herein, we report the investigation of solid electrolyte–current collector interfaces with a self-forming LiI–LiI(HPN)2 solid electrolyte and the role of varying interface design in reducing resistance during cycling.
Cognitive impairment is a core feature of psychotic disorders, but the profile of impairment across adulthood, particularly in African-American populations, remains unclear.
Using cross-sectional data from a case–control study of African-American adults with affective (n = 59) and nonaffective (n = 68) psychotic disorders, we examined cognitive functioning between early and middle adulthood (ages 20–60) on measures of general cognitive ability, language, abstract reasoning, processing speed, executive function, verbal memory, and working memory.
Both affective and nonaffective psychosis patients showed substantial and widespread cognitive impairments. However, comparison of cognitive functioning between controls and psychosis groups throughout early (ages 20–40) and middle (ages 40–60) adulthood also revealed age-associated group differences. During early adulthood, the nonaffective psychosis group showed increasing impairments with age on measures of general cognitive ability and executive function, while the affective psychosis group showed increasing impairment on a measure of language ability. Impairments on other cognitive measures remained mostly stable, although decreasing impairments on measures of processing speed, memory and working memory were also observed.
These findings suggest similarities, but also differences in the profile of cognitive dysfunction in adults with affective and nonaffective psychotic disorders. Both affective and nonaffective patients showed substantial and relatively stable impairments across adulthood. The nonaffective group also showed increasing impairments with age in general and executive functions, and the affective group showed an increasing impairment in verbal functions, possibly suggesting different underlying etiopathogenic mechanisms.
To examine level of participation and satisfaction with the Healthy Savings Program (HSP), a programme that provides price discounts on healthier foods.
For Study 1, a survey was distributed to a random sample of adults who were invited to participate in a version of the HSP that provided a discount for the purchase of fresh produce and discounts on other healthier foods. In Study 2, interviews were conducted with a convenience sample of adults invited to participate in a version of the HSP that provided price discounts on specific products only (no fresh produce discount).
The HSP is provided to all employer-based insurance plan members of a large health plan. Employers can choose to enhance the version of the HSP that their employees receive by paying for a weekly discount on fresh produce.
Employees in employer groups that received the enhanced HSP (Study 1) and employees in an employer group (Study 2) that received the standard HSP.
Among survey respondents in Study 1, 69·3 % reported using the HSP card. Most were satisfied with the fresh produce discount and ease of use of the HSP card. Satisfaction was lower for selection of participating stores, amounts of discounts and selection of discounted products. In Study 2, barriers to the use of the HSP card cited included the limited number of participating stores and the limited selection of discounted products.
Satisfaction with some elements of the HSP was high while other elements may need improvement to increase programme use.
To compare the dosimetric outcomes of linear accelerator-based stereotactic radiotherapy (SRT) techniques—static conformal field (SCF), static conformal arc (SCA) and dynamic conformal arc (DCA), for treating pituitary adenoma and craniopharyngioma.
Materials and methods
Computer image sets of 20 patients with pituitary adenoma or craniopharyngioma and treated with post-operative SRT were selected for this study. For each dataset, three SRT plans, with SCF, SCA and DCA techniques were generated using Brain LAB, iPlan RT V.4.5.3, TPS software. The conformity index (CI), homogeneity index (HI), quality of coverage of the target, dose–volume histograms for the target and organs at risk (OARs) and the time taken to deliver treatment was compared across three sets of plan.
There were 12 patients with pituitary adenoma and eight with craniopharyngioma. The CI and HI were comparable across three techniques. The quality of coverage was superior in DCA technique. OARs were better spared in SCF and DCA techniques. Time taken to deliver treatment was least in SCF technique.
The linac-based SRT techniques SCF, SCA and DCA are efficient in delivering highly conformal and homogenous dose to the target in pituitary adenoma and craniopharyngioma. Among these three techniques, SCF and DCA had acceptable quality of coverage. The dose received by OARs was least in the SCF technique.
Pixelated vision or visual snow has been associated with schizophrenia (Silverstein 2011). The impact of viewing a 3D motion picture on such a visualphenomenon has not heretofore been described.
Case Study: A 28 year old right handed single male three years prior to presentation noticed that all his vision was pixelated. The pixelated vision is panoramic, involving the entire visual field. The pixels are characterized by 10,000 flat white and gray dots measuring 1mm x 1mm. No changes in color, shape, or size were noted in high and low intensity light. White, dark, gray, or multicolored backgrounds had no effect on his vision. The visual distortions are not impacted by head movements, emotions, degree of tiredness, driving, or his hedonic perception of the object being visualized. The pixels were noted to disappear upon closure of both eyes but persisted during monocular vision with either eye. These visual hallucinations were sporadic during the first year and became continuous over the following two years. Two weeks after onset ofpixelated vision he developed auditory hallucinations and hyperacusis. These increased in intensity and frequency to 500-600 times per day. He denied palinopsia, migraines, tinnitus, and photophobia. These hallucinations persisted despite treatment with aripiprazole, paliperidone, lurasidone, olanzapine, clozapine, ziprasidone, benztropine, bupropion, lamotrigine, modafinil, trazodone, atomoxetine, and amphetamine.
Abnormalities in Examination: Hypoverbal, blunted affect, impaired concentration, preoccupied with racing thoughts. Admitted to actively having auditory and visualhallucinations, without suicidal or homicidal ideations. Memory testing: Able to recall 2 out of 4 objects in 3 minutes and 3 out of 4 with reinforcement. Similarities interpreted concretely. Visual Acuity: 20/20 OU. Retinal examination: Normal. Intraocular Pressure: 19 mm OD, 20 mm OS (normal). Automotive Perimetry Testing: Normal. Cover/Uncover: Normal. Near Convergence: 3 inches (normal). Lens or filtered prism have no effect on visual snow. MRI of his brain, EEG, BAER, liver function tests, CBC, vitamin B12, folate, and thyroid function tests were normal. MRA: mild hypoplasia of distal right vertebral artery.
Visual snow has been anecdotally described as static, continuous, and independent of the specific visual environment (McKendrick, 2017). However, thepersistence of visual snow in the presence of 3D movies has never been reported. The visual snow paralleled auditory hallucinations and hyperacusis in frequency and intensity, which suggests there may be generalized hyperexcitability of the brain inducing both auditory and visual hallucinations. Agents that reduce cortical hyperexcitability (i.e., anticonvulsants, anxiolytics) may have efficacy. Treatment with these agents has been described (Ghannam, 2017), warrants further investigation.
Predicting mango mealybug, Rastrococcus iceryoides (Green) (Hemiptera: Pseudococcidae), populations in an organic mango (Mangiferaindica Linnaeus; Anacardiaceae) ecosystem well in advance with reasonable accuracy, will facilitate biological control. In this study, an attempt was made to predict the population of mango mealybug using abiotic weather parameters as independent variables. The study was conducted at the Indian Council of Agricultural Research – Indian Institute of Horticultural Research, Bengaluru, India (12°8'N; 77°35'E). Among the abiotic variables, maximum temperature was found relevant for predicting the population of the mealybug based on significant correlations. It was found that a prediction model using maximum temperature as independent variable with R2 is most ideal. This prediction model, when considered three to four weeks in advance of an infestation, could help farmers to gear up with biological control.
We have spectra, colours and morphologies from the CFHT for 240 cluster members and 80 field galaxies over a 7 × 46 arcmin field. The cluster galaxies show strong radial gradients in colour, morphology, and spectrum. The central group has only red early-type galaxies of high central concentration, which must have formed at least 5 Gy ago. The population becomes bluer and shows an increasing fraction of disk morphology and recent star-formation with clustocentric radius, and eventually blends into the field. However, the fraction of blue galaxies is significantly lower than in Butcher-Oemler clusters, and there are only two starburst galaxies (one of which is the cluster cD). Fitting of line measures with stellar population models indicates that star-formation has been truncated in the 15-20% of the cluster galaxies that have strong Hδ absorption, and that these galaxies are not all blue. There is evidence that cluster galaxies are dusty compared with the field. The morphology gradient can be fit with models of disk fading. However, there is a small fraction of interacting and merging galaxies, which must play a part in the population evolution. The cluster is accreting from the field in a non-violent way, including some distinct subgroups. This is different from what is seen at both higher and lower redshift, and if generally true, suggests a high Omega universe.
These results are being published in detail elsewhere.
We present NH3(J,K) = (1,1) observations toward CS(2,1) sources in the southern hemisphere, obtained with the Itapetinga Radio Telescope, that exhibit departure from LTE conditions. The mechanism of selective trapping in the hyperfine transitions of NH3(J, K) =(2,1)-(1,1) is invoked to explain the non-thermal population in the NH3(J, K) = (1,1) hyperfine states. This effect is relevant only when the width of the hyperfine lines lie between 0.3 and 0.6 km s−1. Due to this restriction, the assumption that the molecular cloud is formed by clumps, which produce spectra within this line-width interval seems to be a natural explanation for the non-thermal population. The observed spectra can be the result of the superposition of individual clump spectra with different central velocities. This model was applied to determine the physical conditions of the observed regions, providing satisfactory results for most of them. However, for some sources the model is not adequate to reproduce the observations, indicating that some other effects should be included, such as IR continuum, that was neglected in the radiative transfer calculations.
Since the very beginning of the Itapetinga 45-ft antenna operations in 1971, there were plans to use it as a southern hemisphere VLBI terminal for high north-south resolution. The first successful VLBI tests were performed on water vapor lines in cooperation with Haystack Observatory in 1978 in one of the last runs using the MkI system. This cooperation led to the construction of a MkII terminal for Itapetinga years later (1981–1983). Astrophysical VLBI runs have been carried out since 1984, with the cooperation of Caltech, producing maps of unique resolution on stronger quasars, especially on 3C273 whose evolution has been followed since then. Recently, Bonn joined the collaboration in astrophysical VLBI programs. Itapetinga also participated successfully in geodetic surveys, and in the Vega-Venus mission, in collaboration with JPL and French organizations CNES, Observatoire de Paris and IGN. Plans for continuation and expansion of the Itapetinga VLBI participation in international efforts depend strongly on support to maintain and upgrade instrumentation at the Brazilian Radio Observatory.
Kefir is a fermented milk obtained by the activity of kefir grains which are composed of lactic and acetic acid bacteria, and yeasts. Many beneficial health effects have been associated with kefir consumption such as stimulation of the immune system and inhibition of pathogenic microorganisms. The biological activity of kefir may be attributed to the presence of a complex microbiota as well as the microbial metabolites that are released during fermentation. The aim of this work was to characterise the non-microbial fraction of kefir and to study its antagonism against Escherichia coli, Salmonella spp. and Bacillus cereus. During milk fermentation there was a production of organic acids, mainly lactic and acetic acid, with a consequent decrease in pH and lactose content. The non-microbial fraction of kefir added to nutrient broth at concentrations above 75% v/v induced a complete inhibition of pathogenic growth that could be ascribed to the presence of un-dissociated lactic acid. In vitro assays using an intestinal epithelial cell model indicated that pre-incubation of cells with the non-microbial fraction of kefir did not modify the association/invasion of Salmonella whereas pre-incubation of Salmonella with this fraction under conditions that did not affect their viability significantly decreased the pathogen's ability to invade epithelial cells. Lactate exerted a protective effect against Salmonella in a mouse model, demonstrating the relevance of metabolites present in the non-microbial fraction of kefir produced during milk fermentation.
In 1979 when accelerator mass spectrometry was started in the Netherlands, Gove (1978) and Litherland (1980) demonstrated that a tandem accelerator is eminently suited for this work. Isotope ratios below 10−15 could be determined and applications were stimulated on numerous fields of research. 14C dating in particular would become an important application because smaller samples could be employed and more complex dating problems could be attacked. However, the 5% accuracy reached at that time had to be improved towards the 0.5% obtained with the conventional method of counting decays. Purser and Hanley (1978) pointed out that this high accuracy could be reached in facilities especially dedicated to dating. Rapid switching between measurements on different isotopes turned out to be crucial (Suter et al, 1981). We decided to proceed in two phases. In the first phase, the existing EN-tandem facility would be used as before and modified for the detection of 14C ions. From measurements with 14C ions from different samples, information would be obtained about the limitations of the existing facility. In the second phase, this information would be used to develop a facility in which accurate measurements of isotope ratios can be performed for elements throughout the periodic system. Conventional 14C dating will be extended in collaboration with the Isotope Physics Laboratory in Groningen. Also, applications with other elements will be studied. The improved facility is scheduled for operation in the spring of 1983.
The higher spatial resolution and sensitivity of ISO allowed several extragalactic surveys to be extended to greater depth than obtained with IRAS. With the extended wavelength range deep surveys were performed for the first time at wavelengths up to ~ 200 μm. They favour galaxy models with strong evolution. With ISO's new capabilities the spectral energy distributions of larger samples of ULIRGs in the local universe and those of quasars and radio galaxies were determined. These data are applicable as templates to the more distant universe. Foreground components from zodiacal light and cirrus to the intracluster dust emission were studied in connection with their separation from the extragalactic background radiation.
We present our approach of visibility modeling of disks around low-mass (< 2 M⊙) young stellar objects (YSOs). We compiled an atlas based on mid-infrared interferometric observations from the MIDI instrument at the VLTI. We use three different models to fit the data. These models allow us to determine overall sizes (and the extent of the inner gaps) of the modeled circumstellar disks.
Atomic force microscopy is employed to study the structural changes in the morphology and physical characteristics of asphaltene aggregates as a function of temperature. The exotic fractal structure obtained by evaporation-driven asphaltene aggregates shows an interesting dynamics for a large range of temperatures from 25°C to 80°C. The changes in the topography, surface potential and adhesion are unnoticeable until 70°C. However, a significant change in the dynamics and material properties is displayed in the range of 70°C - 80°C, during which the aspahltene aggregates acquire ‘liquid-like’ mobility and fuse together. This behaviour is attributed to the transition from the pure amorphous phase to a crystalline liquid phase which occurs at approximately 70°C as shown by using Differential Scanning Calorimetry (DSC). Additionally, the charged nature of asphaltenes and bitumen is also explored using kelvin probe microscopy. Such observations can lead to the development of a rational approach to the fundamental understanding of asphaltene aggregation dynamics and may help in devising novel techniques for the handling and separation of asphaltene aggregates using dielectrophoretic methods.
We present the first quantitative assessment of combustion dynamics of on-chip porous silicon (PS) energetic material using sulfur and nitrate-based oxidizers with potential for improved moisture stability and/or minimized environmental impact compared to sodium perchlorate (NaClO4). Material properties of the PS films were characterized using gas adsorption porosimetry, and profilometry to calculate specific surface area, porosity and etch depth. The PS/sulfur energetic composite was formed using three pore loading techniques, where the combustion speeds ranged from 2.9 – 290 m/s. The nitrate-based oxidizers were solution-deposited using different compatible solvents, and depending on the metal-nitrate yielded combustion speeds of 3.1 – 21 m/s. Additionally, the combustion enthalpies from bomb calorimetry experiments are reported for the alternative PS/oxidizer systems in both nitrogen and oxygen environments.