Addenda to the insect fauna of Al-Baha Province,Kingdom of Saudi Arabia with zoogeographical notes

The first list of insects (Arthropoda: Hexapoda) of Al-Baha Province, Kingdom of Saudi Arabia (KSA) was published in 2013 and contained a total of 582 species. In the present study, 142 species belonging to 51 families and representing seven orders are added to the fauna of Al-Baha Province, bringing the total number of species now recorded from the province to 724. The reported species are assigned to recognized regional zoogeographical regions. Seventeen of the species are recorded for the first time for KSA, namely: Platypleura arabica Myers [Cicadidae, Hemiptera]; Cletomorpha sp.; Gonocerus juniperi Herrich-Schäffer [Coreidae, Hemiptera]; Coranus lateritius (Stål); Rhynocoris bipustulatus (Fieber) [Reduviidae, Hemiptera]; Cantacader iranicus Lis; Dictyla poecilla Drake &; Hill [Tingidae, Hemiptera]; Mantispa scabricollis McLachlan [Mantispidae, Neuroptera]; Cerocoma schreberi Fabricius [Meloidae, Coleoptera]; Platypus parallelus (Fabricius) [Curculionidae, Coleoptera]; Zodion cinereum (Fabricius) [Conopidae, Diptera]; Ulidia ?ru?ceps Becker [Ulidiidae, Diptera]; Atherigona reversura Villeneuve [Muscidae, Diptera]; Aplomya metallica (Wiedemann); Cylindromyia sp. [Tachinidae, Diptera]; Messor semirufus (André); and Nesomyrmex denticulatus (Mayr) [Formicidae, Hymenoptera]. Also, the reduviid bug Dasycnemus sahlbergi Bergroth, that was questionably recorded from KSA is confirmed herein as occurring in KSA. The generic name Peirates (Reduviidae, Hemiptera) and the specific name of Apis florea Fabricius (Apidae, Hymenoptera) were inadvertently misspelled in the original list and are corrected here. Zoogeographically, the present study supports the original study conclusion that the insect species composition of Al-Baha Province is strongly affiliated with the Afrotropical Region rather than to the Palearctic Region or the Eremic Zone. Our insect surveys emphasize the fact that parts of the Arabian Peninsula, including Al-Baha Province, ought to be considered part of the Afrotropical Region rather than in the Palaearctic Region or the Eremic Zone.     

Phytotelmata colonization in bamboo (Guadua sp.) culms in northeast Argentina

This study aimed to determine the susceptibility of stumps and internodes of bamboos to colonization by different types of macroinvertebrates and the formation of communities of different complexity. Semi-controlled field studies were carried out in a subtropical area of Argentina to analyse community structure, species richness of the aquatic macroinvertebrate communities and co-occurrences of predators and prey to delineate the food webs. Water-filled bamboos were sampled every season during a year by removing, without replacing, all water and macroinvertebrates. This study shows that the variation in the morphology of the container provides different resources, leading to segregation of species per container type, and allowing each of them to establish aquatic communities with differences in diversity. The Diptera was best represented in the communities of bamboos, where Culicidae showed the highest species richness and Ceratopogonidae were the most abundant numerically. Eleven taxa were present in both phytotelmata, 12 were unique in internodes and 13 in stumps. The community in internodes was composed of 21 taxa where mosquitoes were represented by Sabethini and Toxorhynchitini. By contrast, stumps were colonized by 24 taxa and Ceratopogonidae were numerically dominant. Regarding food webs established in stumps and internodes, no differences in length were found, except for the species that played equivalent roles in each of the studied phytotelmata.     

BCL6 enables Ph+ acute lymphoblastic leukaemia cells to survive BCR-ABL1 kinase inhibition

Tyrosine kinase inhibitors (TKIs) are widely used to treat patients with leukaemia driven by BCR-ABL1 (ref. 1) and other oncogenic tyrosine kinases. Recent efforts have focused on developing more potent TKIs that also inhibit mutant tyrosine kinases. However, even effective TKIs typically fail to eradicate leukaemia-initiating cells (LICs), which often cause recurrence of leukaemia after initially successful treatment. Here we report the discovery of a novel mechanism of drug resistance, which is based on protective feedback signalling of leukaemia cells in response to treatment with TKI. We identify BCL6 as a central component of this drug-resistance pathway and demonstrate that targeted inhibition of BCL6 leads to eradication of drug-resistant and leukaemia-initiating subclones.     

A Prototype of CAPP System for Rotational Parts

Noticing in recent years that the world is running out of mineral resources, the price of engineering materials will continually rise in the future, the percentage of the cost of manufactured part that is due to the cost of materials is also rising. The amount of material must be removed away to produce the final product should be minimized, excess stock will increase not only the material cost, but also processing cost, fixture cost, tooling cost, and increases machine cycle times. This paper proposed a va...     

Structural characterization of AA 2024-MoSi2 nanocomposite powders produced by mechanical milling

Nano-sized MoSi₂ powder was produced successfully from commercially available MoSi₂ by a mechanical milling process carried out for 100 h, and mechanical alloying was employed to synthesize AA 2024-MoSi₂ nanocomposites. The effects of MoSi2 reinforcement and mechanical milling on the structure, morphology, and iron contamination of the produced materials were investigated using X-ray diffraction, scanning electron microscopy, and atomic absorption spectrometry. It is revealed that the morphology of the aluminum alloy changes continuously during milling from spherical to plate-like, irregular, and finally equiaxed. The presence of MoSi₂ reinforcement accelerates the milling process and results in a smaller average particle size. The Williamson-Hall method determined that the crystallite size of the aluminum alloy in the composite powder is smaller than that of the unreinforced alloy at the same milling time and this size reaches 45 nm after 16 h milling time. The Fe contamination content is higher for the nanocomposite in comparison with the unreinforced alloy because of the wearing role of MoSi₂ hard particles.     

Structural basis for Duffy recognition by the malaria parasite Duffy-binding-like domain

Molecular processes that govern pathogenic features of erythrocyte invasion and cytoadherence in malaria are reliant on Plasmodium-specific Duffy-binding-like domains (DBLs). These cysteine-rich modules recognize diverse host cell-surface receptors during pathogenesis. DBLs of parasite erythrocyte-binding proteins mediate invasion, and those from the antigenically variant P. falciparum erythrocyte membrane protein 1 (PfEMP1) have been implicated in cytoadherence. The simian and human malarial parasites, P. knowlesi and P. vivax, invade human erythrocytes exclusively through the host DARC receptor (Duffy antigen receptor for chemokines). Here we present the crystal structure of the P. knowlesi DBL domain (Pkalpha-DBL), which binds to DARC during invasion of human erythrocytes. Pkalpha-DBL retains the overall fold observed in DBLs from P. falciparum erythrocyte-binding antigen (EBA)-175 (ref. 4). Mapping the residues that have previously been implicated in binding highlights a fairly flat but exposed site for DARC recognition in subdomain 2 of Pkalpha-DBL; this is in sharp contrast to receptor recognition by EBA-175 (ref. 4). In Pkalpha-DBL, the residues that contact DARC and the clusters of residues under immune pressure map to opposite surfaces of the DBL, and suggest a possible mechanism for immune evasion by P. vivax. Our comparative structural analysis of Pkalpha-DBL and P. falciparum EBA-175 provides a framework for the understanding of malaria parasite DBLs, and may affect the development of new prophylactic and therapeutic strategies.     

Nanotechnology: fundamental research to product development

The concept of an integrated "lab on a chip" has long been a goal for the micro-electro-mechanical-systems(MEMS) community.This would entail the integration of not only the sampling and analysis of various functions,but also the ability to transmit this information off the chip to a central repository.This paper describes the initial steps in the fabrication of a "lab on a chip" which would continually analyze blood sampled via microneedles using techniques such as nano plasmonics,specifically,concentrations of glucose.The analysis could then be transmitted off the chip using digital signal processing.This paper describes the analysis and optimization of the microneedle shape and size and the fabrication of the resulting needles in silicon using deep reactive ion etching(DRIE).The paper also describes the opportunities for fabrication of such needles in alternative materials and describes the issues that still have to be overcome before such an integrated device is realized.     

Auditing as the Dissolution of Corruption

This paper develops a new discourse of control. The new discourse rejects the view that control is achieved through inspections and information alone, and supports the view that effective control means self-control and effective communications, both being necessary conditions to enable organizations to perform well. In this discourse, corruption is taken to be, among other things, the outcome of fragmentation in communications. Therefore, a movement toward a recursive organization of the State is offered as a way to countering corruption. This discourse was developed during a project for Institutional Change and Strengthening implemented at the Contraloría General de la República (CGR), in Colombia from 1995 to 1998. As part of the discourse we offer a distinction among traditional auditing practices, second-order auditing, and integrated systemic auditing practices.     

Anthocyanins ofDioscorea alata L.

Résumé Trois anthocyanines ont été extraits de tubercules d'une variété de l'ignameD. alata à chair pourpre. Tous les 3 sont des glycosides de la cyanidine: le pigment principal est le cyanidine-3,5-diglucoside.     

Evidence for a macroscopic electric field in the sedimentation profiles of charged colloids

The determination of molecular masses from barometric sedimentation profiles, a main topic in ultracentrifugal analysis, is thought to be quantitatively correct for non-interacting particles. Whereas this expectation is justified for uncharged colloids or macromolecules at low volume fractions, early ultracentrifugation studies on charged particles had already indicated that the obtained masses might be much too low. More recently, expanded sedimentation profiles have been observed for charged particles, sometimes inflated by orders of magnitude relative to the barometric prediction, which highlights a shortcoming in our understanding of centrifugation of even very dilute charged species. Theory and simulations, anticipated by various authors, now propose that strongly non-barometric sedimentation profiles might be caused by an internal macroscopic electric field that, even for non-interacting particles, significantly decreases the buoyant particle mass. The existence of this field and its intriguing consequences still lack experimental verification. Here we report ultracentrifugation experiments on charged colloidal silica spheres, showing both the existence of such a macroscopic electric field and its drastic effects on the sedimentation profiles of very dilute dispersions at low ionic strength.