Images of asteroid 21 Lutetia: a remnant planetesimal from the early Solar System

Images obtained by the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) cameras onboard the Rosetta spacecraft reveal that asteroid 21 Lutetia has a complex geology and one of the highest asteroid densities measured so far, 3.4 ± 0.3 grams per cubic centimeter. The north pole region is covered by a thick layer of regolith, which is seen to flow in major landslides associated with albedo variation. Its geologically complex surface, ancient surface age, and high density suggest that Lutetia is most likely a primordial planetesimal. This contrasts with smaller asteroids visited by previous spacecraft, which are probably shattered bodies, fragments of larger parents, or reaccumulated rubble piles.     

Root exudation of sugars,amino acids,and organic acids by maize as affected by nitrogen,phosphorus, potassium,and iron deficiency

Root exudates play a major role in the mobilization of sparingly soluble nutrients in the rhizosphere. Since the amount and composition of major metabolites in root exudates from one plant species have not yet been systematically compared under different nutrient deficiencies, relations between exudation patterns and the type of nutrient being deficient remain poorly understood. Comparing root exudates from axenically grown maize plants exposed to N, K, P, or Fe deficiency showed a higher release of glutamate, glucose, ribitol, and citrate from Fe‐deficient plants, while P deficiency stimulated the release of γ‐aminobutyric acid and carbohydrates. Potassium‐starved plants released less sugars, in particular glycerol, ribitol, fructose, and maltose, while under N deficiency lower amounts of amino acids were found in root exudates. Principal‐component analysis revealed a clear separation in the variation of the root‐exudate composition between Fe or P deficiency versus N or K deficiency in the first principal component, which explained 46% of the variation in the data. In addition, a negative correlation was found between the amounts of sugars, organic and amino acids released under deficiency of a certain nutrient and the diffusion coefficient of the respective nutrient in soils. We thus hypothesize that the release of dominant root exudates such as sugars, amino acids, and organic acids by roots may reflect an ancient strategy to cope with limiting nutrient supply.     

Root growth and phosphorus uptake in wide‐ and narrow‐row soybeans

Most of the research comparing the effect of different row spacing on seed yield in soybeans [Glycine max (L.) Merr.] has been focused on row spacing effects on aboveground crop characteristics such as leaf area, right interception, pod number, or biomass accumulation and their relationships with seed yield. Little work has been done on the effects of narrow‐row spacing on root distribution. Plant distribution may also affect root distribution and interroot competition, and therefore, exploration and use of soil resources. A field experiment was carried out on the Pampas (Argentina) to determine the effect of narrow‐row spacing on root distribution within the topsoil in soybean, and whether different root distributions affect phosphorus uptake. In December 1993, soybeans were planted at two row spacings, narrow rows (0.35 m) and wide rows (0.70 m). Root density was measured during seed filling (92 days after planting) at several points within the inter‐row space down to a soil depth of 30 cm. Aboveground biomass was harvested at maturity and phosphorus (P) uptake was measured. Below the row line, narrow‐row soybeans showed a greater root density than the wide row treatment at 5–10 cm depth, while roots of the wide‐row soybeans had more lateral growth. Root density at both sides of the row down to a depth of 5 cm was greater for the wide‐row treatment. Average root density for each depth for a section of 70 cm wide across the row line indicated there was no significant difference between treatments at any depth. The fewer number of rows for the wide‐row spacing was compensated by a greater lateral extension of roots within the interrow space. This compensation resulted in a similar root density at each depth for both planting patterns, narrow and wide rows. Aboveground biomass and phosphorus concentration in plant tissue at maturity were not affected by row spacing. A similar phosphorus uptake for both treatments was consistent with the lack of effect of the different plant distribution on soil exploration by roots and on aboveground biomass accumulation.     

FDI in China:Policies and Economic effects

The rapid growth of the world population since 1950 and the contribution matching the GDP and the income per capita has been seen in the increase competition for FDI of the past few years. Therefore, it is well-known that FDI can contribute to economic development not only by being a source of foreign capital, but also by providing employment, opportunities, increasing competition, and most importantly transferring skills and knowledge done by spillover effects.However, these positive effects are not automatic for host countries in the long run and depend largely on the policies taking in place. Having a closer look at the People′s Republic of China(PRC) and by examining how the policies in place have attracted FDI and looking to the contributions that foreign direct invest can make to the recipient country,showing the effects in industries that are economic pushers such as the mining industry can give us the general idea. Hence, FDI has contributed positively to Chinese economic development; there are challenges in order that the People′s Republic China can effectively continue benefitting from it at a larger extent.     

Correction to: Thermal biology of Tuta absoluta: demographic parameters and facultative diapause

Journal of Pest Science - Formula, Equation 2 and the table 3 are published incorrectly in the original publication of the article. The correct version of the article is given below     

THORACIC COMPUTED TOMOGRAPHY,ANGIOGRAPHIC COMPUTED TOMOGRAPHY,AND PATHOLOGY FINDINGS IN SIX CATS EXPERIMENTALLY INFECTED WITH AELUROSTRONGYLUS ABSTRUSUS

Aelurostrongylus abstrusus infection is common in endemic areas and may cause severe respiratory clinical signs. Computed tomography (CT) is an important tool to diagnose pulmonary disease, because it allows detection of small lesions and discrimination of superimposed structures. The purpose of this study was to characterize by CT and angiographic CT the pulmonary lesions in six cats before, and 48 and 81 days after inoculation with 100 or 800 A. abstrusus infective larvae. Histological examination of the accessory lung lobe was performed to determine the microscopic, pathomorphologic correlate of the CT findings. The predominant CT lesion consisted of multiple nodules of varying size distributed throughout the lungs, severity depending on infectious dose. The histological correlate of the nodular lesions was multifocal dense granulomatous to mixed inflammatory cell infiltrates, including eosinophils distributed in the parenchyma and obliterating the alveoli. Marked, multifocal, dose‐dependent thickening of the bronchi and adjacent interstitial changes blurred the margins of the outer serosal surface of the bronchi and vessels. Histologically, this was due to peribronchial mixed cell inflammation. During the course of infection some of the nodular and peribronchial changes were replaced by areas of ground‐glass opacity. In addition to providing detailed depiction of pulmonary lesions resulting from an infectious cause and clearly defining lesions with respect to time and severity of infection, CT allowed quantitative assessment of bronchial thickness and lymph node size during the course of disease. Findings indicated that CT characteristics of this disease are consistent with pathologic findings.     

Tick saliva induces regulatory dendritic cells: MAP-kinases and Toll-like receptor-2 expression as potential targets

Ticks (Acari: Ixodidae) are bloodsucking ectoparasitic arthropods of human and veterinary medical importance. Tick saliva has been shown to contain a wide range of bioactive molecules with vasodilatory, antihemostatic, and immunomodulatory activities. We have previously demonstrated that saliva from Rhipicephalus sanguineus ticks inhibits the maturation of dendritic cells (DCs) stimulated with LPS. Here we examined the mechanism of this immune subversion, evaluating the effect of tick saliva on Toll-like receptor (TLR)-4 signalling pathway in bone marrow-derived DCs. We demonstrated that R. sanguineus tick saliva impairs maturation of DCs stimulated with LPS, a TLR-4 ligand, leading to increased production of interleukin (IL)-10 and reduced synthesis of IL-12p70 and TNF-α. The immunomodulatory effect of the tick saliva on the production of pro-inflammatory cytokines by DCs stimulated with LPS was associated with the observation that tick saliva inhibits the activation of the ERK 1/2 and p38 MAP kinases. These effects were independent of the expression of TLR-4 on the surface of DCs. Additionally, saliva-treated DCs also presented a similar pattern of cytokine modulation in response to other TLR ligands. Since the recent literature reports that several parasites evade immune responses through TLR-2-mediated production of IL-10, we evaluated the effect of tick saliva on the percentage of TLR-2⁺ DCs stimulated with the TLR-2 ligand lipoteicoic acid (LTA). The data showed that the population of DCs expressing TLR-2 was significantly increased in DCs treated with LTA plus saliva. In addition, tick saliva alone increased the expression of TLR-2 in a dose- and time-dependent manner. Our data suggest that tick saliva induces regulatory DCs, which secrete IL-10 and low levels of IL-12 and TNF-α when stimulated by TLR ligands. Such regulatory DCs are associated with expression of TLR-2 and inhibition of ERK and p38, which promotes the production of IL-10 and thus down-modulates the host's immune response, possibly favouring susceptibility to tick infestations.