Spatial Variability of Turbulent Mixing in the Abyssal Ocean

Ocean microstructure data show that turbulent mixing in the deep Brazil Basin of the South Atlantic Ocean is weak at all depths above smooth abyssal plains and the South American Continental Rise. The diapycnal diffusivity there was estimated to be less than or approximately equal to 0.1 x 10(-4) meters squared per second. In contrast, mixing rates are large throughout the water column above the rough Mid-Atlantic Ridge, and the diffusivity deduced for the bottom-most 150 meters exceeds 5 x 10(-4) meters squared per second. Such patterns in vertical mixing imply that abyssal circulations have complex spatial structures that are linked to the underlying bathymetry.     

A long-snouted predatory dinosaur from africa and the evolution of spinosaurids

Fossils discovered in Lower Cretaceous (Aptian) rocks in the Tenere Desert of central Niger provide new information about spinosaurids, a peculiar group of piscivorous theropod dinosaurs. The remains, which represent a new genus and species, reveal the extreme elongation and transverse compression of the spinosaurid snout. The postcranial bones include blade-shaped vertebral spines that form a low sail over the hips. Phylogenetic analysis suggests that the enlarged thumb claw and robust forelimb evolved during the Jurassic, before the elongated snout and other fish-eating adaptations in the skull. The close phylogenetic relationship between the new African spinosaurid and Baryonyx from Europe provides evidence of dispersal across the Tethys seaway during the Early Cretaceous.     

Interaction of insecticides with the Ca2+-pump activity of sarcoplasmic reticulum

The organophosphorus insecticides, parathion and azinphos (10^?5-10^?4M), significantly stimulate the Ca²⁺-pump activity of sarcoplasmic reticulum, while malathion has a limited effect. The rates of Ca²⁺ translocation and ATP hydrolysis are both stimulated and, apparently, the $\text{Ca}{}^{\mathrm{2+}}\text{ATP}$ ratio is improved. Parathion and azinphos maximally increase this ratio by 26 and 14%, respectively. The organochlorine compounds, DDT and aldrin, also stimulate the Ca²⁺ pump, and lindane has a reduced effect. These effects are smaller than those observed for parathion and azinphos. The order of effectiveness is similar to the toxicity of the compounds to mammals and can be described as follows: parathion > azinphos > DDT ≈ aldrin > malathion ≈ lindane.     

Roles of bootstrap resampling,measure of central tendency,and method for calculating thermal units when developing phenology models for pest management

The successful development of phenology models from field studies depends on many factors, some of which are entirely under the control of pest managers. For example, one such factor is the choice of method for calculating thermal units. In this study, we have demonstrated that four methods for calculating thermal units provided for acceptable predictions of one phenological event of one insect species, while another method for calculating thermal units did not. The measure of central tendency (mean or median) that is used to estimate lower developmental temperatures and required thermal summations is another factor that pest managers can control when developing phenology models from field studies. Here, we show that predictions that were made when using phenology models based on median lower developmental temperatures and median required thermal summations were superior to predictions that were made when using phenology models based on mean lower developmental temperatures and mean required thermal summations. The use of bootstrap vs. non-bootstrap estimates of lower developmental temperatures and required thermal summations is yet another factor that pest managers can control when developing phenology models from field studies. In this study, we found that calculating and using bootstrap estimates of lower developmental temperatures and required thermal summations in phenology models did not improve the predictions of one phenological event for one insect species. The implications of these and other findings are discussed.     

Pyogenic bacterial infections in humans with MyD88 deficiency

MyD88 is a key downstream adapter for most Toll-like receptors (TLRs) and interleukin-1 receptors (IL-1Rs). MyD88 deficiency in mice leads to susceptibility to a broad range of pathogens in experimental settings of infection. We describe a distinct situation in a natural setting of human infection. Nine children with autosomal recessive MyD88 deficiency suffered from life-threatening, often recurrent pyogenic bacterial infections, including invasive pneumococcal disease. However, these patients were otherwise healthy, with normal resistance to other microbes. Their clinical status improved with age, but not due to any cellular leakiness in MyD88 deficiency. The MyD88-dependent TLRs and IL-1Rs are therefore essential for protective immunity to a small number of pyogenic bacteria, but redundant for host defense to most natural infections.     

Gracilaria gracilis (Gracilariales,Rhodophyta) from Dakhla (Southern Moroccan Atlantic Coast) as Source of Agar: Content,Chemical Characteristics,and Gelling Properties

Agar is a sulfated polysaccharide extracted from certain marine red algae, and its gel properties depend on the seaweed source and extraction conditions. In the present study, the seaweed Gracilaria gracilis (Gracilariales, Rhodophyta) from Dakhla (Moroccan Atlantic Coast) was investigated for its agar content, structure, and gel properties. The agar yields of G. gracilis were 20.5% and 15.6% from alkaline pretreatment and native extraction, respectively. Agar with alkaline pretreatment showed a better gelling property supported by higher gel strength (377 g·cm⁻²), gelling (35.4 °C), and melting (82.1 °C) temperatures with a notable increase in 3,6-anhydro-galactose (11.85%) and decrease in sulphate (0.32%) contents. The sulfate falling subsequent to alkaline pretreatment was verified through FT-IR spectroscopy. The ¹³C NMR spectroscopy showed that alkaline-pretreated agar has a typical unsubstituted agar pattern. However, native agar had a partially methylated agarose structure. Overall, this study suggested the possibility of the exploitation of G. gracilis to produce a fine-quality agar. Yet, further investigation may need to determine the seasonal variability of this biopolymer according to the life cycle of G. gracilis.     

Trajectory and cluster resilience elements: The case of the Brazilian wine cluster of the Serra Gaúcha

The recent economic, technological, and social shocks have led to a period of high economic uncertainty. The term “economic resilience” has been used to describe how regional clusters deal with and adapt to various shocks. This paper aims to analyze the elements that influence the resilience trajectory of a cluster. We conduct qualitative and exploratory research on the centennial Wine Cluster in Serra Gaúcha, Brazil, using data sources, interviews, and documents. To this end, we first identify seven elements that influence cluster resilience from the literature review. Subsequently, through an empirical case study, we verify whether these elements could represent the resilience of clusters. The results show that these seven elements are integrable and represent dimensions that explain the resilience of the cluster analyzed. Moreover, the findings highlight that resilience and resistance to crises are the historical results of improvements and the development of new routines for clustered companies. This study contributes to the cluster resilience literature and presents elements explaining how regions can adapt to and deal with shocks.     

Structure-function relationship of vermicompost humic fractions for use in agriculture

Purpose

The use of humic substances (HS) in agriculture is beneficial and has positive environmental impacts. However, to optimize the use of HS possible links between their structural characteristics and bioactivity must be shown. The goal of this study is to evaluate the bioactivity of different humic fractions extracted from vermicompost (VC) in rice plants and to shed light to possible structure-function relationships.

Materials and methods

Humic-like fractions were obtained from cattle manure vermicompost processed by African nightcrawlers (Eudrilus eugeniae spp.). Humic-like acid fraction using only water as extractor (HLAw), HLA fraction extracted following the International Humic Substances Society (IHSS) recommended method, and the solid residue (humified residual (HR)) after extraction of HLA were characterized using complementary chemical, physic, and spectroscopic technics (elemental composition, UV-Vis and Fourier transform infrared spectroscopy (FTIR) spectroscopies, ¹³C-CP MAS NMR, and MEV). Biological activity of the three HS was conducted in growth chambers and measured in roots using WinRhizo Arabidopsis software. Principal component analysis (PCA) was used to find a grouping pattern between the structural variables evaluated and the obtained root parameters.

Results and discussion

Differences were found in elemental composition among HS with larger C/N ratio in HR than in HLA and HLAw. HLA and HLAw FTIR spectra showed carboxyl band at 1714.66 cm^?1 better resolved than in HR. Bands at 1642 cm^?1 (amide I) and 1510 cm^?1 (lignin), were better resolved in HLA. ¹³C-NMR showed the following order of aromaticity: HLA > HLAw > HR. For HLAw bioactivity, the structures C_Alkyl-H,R, C_C=O, and C_COO-H,R correlated with the number and growth of smaller root. The aromatic C_Ar-H,R, C_Ar-O,N, and aliphatic C_Alkyl-O,N, C_Alkyl-O, and C_Alkyl-di-O structures in HLA, correlated with larger roots growth. HR also stimulated root growth and development in rice plants.

Conclusions

Aliphatic and oxygenated structures in HLAw showed a relation with induction of initial root emissions, whereas the presence of aromatic compounds in HLA was related with root growth stimulation activity. Higher concentration of HLAw was necessary to produce an equivalent stimulus compared with HLA; it could indicate that, although both fractions showed similar types of structures in their composition, differences in the predominant structures may be determining different effects on the root.

     

Surface Deformation and Lower Crustal Flow in Eastern Tibet

Field observations and satellite geodesy indicate that little crustal shortening has occurred along the central to southern margin of the eastern Tibetan plateau since about 4 million years ago. Instead, central eastern Tibet has been nearly stationary relative to southeastern China, southeastern Tibet has rotated clockwise without major crustal shortening, and the crust along portions of the eastern plateau margin has been extended. Modeling suggests that these phenomena are the result of continental convergence where the lower crust is so weak that upper crustal deformation is decoupled from the motion of the underlying mantle. This model also predicts east-west extension on the high plateau without convective removal of Tibetan lithosphere and without eastward movement of the crust east of the plateau.