Explore the vast range of titles available.

Background Entamoeba histolytica , an enteric pathogen, causes disease by adhering to and destroying the host tissues. The interaction between the parasite and host tissue enables the rewiring of gene expression and global membrane trafficking in the parasite. A fine balance between endocytosis and exocytosis of cargoes/receptors is required to establish infection in the host. Multivesicular bodies (MVBs) act as sorting platforms, delivering cargoes/receptors to lysosomes for degradation or secreting their contents through plasma membrane fusion. Some small GTPases are known to control MVB biogenesis in various organisms. However, the functional contribution of Rab GTPases in MVB biogenesis is poorly studied in E. histolytica . Results Here, we identified a novel atypical protein RabD2, with an N-terminal glutamic acid-lysine rich motif and a C-terminal conserved Rab domain. Our biochemical and cell biological assays provide evidence that RabD2 self-associates, and this interaction is controlled by the N-terminal EK-rich motif and the GTPase activity mutants. RabD2 localizes on the surface of MVBs and controls their biogenesis. In line with these findings, overexpression of RabD2 upregulates ubiquitination levels, directing the decreased abundance of the heavy chain of GalNAc lectin, ultimately leading to decreased adherence of E. histolytica trophozoites to host cells. Conclusions Thus, amoebic RabD2 is a new class of Rab protein that forms high-ordered self-association variants and controls adhesion to the host cells, which impacts the pathogenesis of E. histolytica through the biogenesis of MVBs.

PurposeThis paper aims to propose an elementary approach towards the measurement of a globoidal cam profile used in an automatic tool changer (ATC) of computer numerical control (CNC) machines.Design/methodology/approachA simple and unique online method has been designed for the profile metrology of the cam. This simple methodology will replace the traditional methodology of profile metrology of cam by coordinate measuring machine (CMM). A globoidal cam with an indexable turret and roller follower (rotating in an enclosed track) has been evaluated in our analysis. This analysis plays a significant role in the performance determination of the cam as well as the ATC of CNC machines.FindingsA novel model has been designed and implemented to investigate the profile of a globoidal cam. The proposed methodology becomes an enhancement over the old methodology, i.e. measurement through CMM. Theoretical analysis and practical implementation prove the significance of the method.Originality/valueAn enhanced methodology to effectively measure the globoidal cam profile has been proposed. The practical implication of the proposed methodology remains for the CNC machine tool and ATC manufacturers. Finally, analytical explorations have been carried out to prove the validity of the proposal.

PurposeThis paper aims to investigate the performance and positioning accuracy of computer numerical controlled (CNC) feed drive system using a ball screw-based pre-loading impact factor.Design/methodology/approachInitially, axial displacement of support bearings has been computed in relation to the different preload values. Among the computed values, a basic rule equation has been developed for the calculation of elongation in the bearings. The value of displacements computed from the developed equation has been considered as a pre-loading value, and its behavior on the feed drive system has been analyzed.FindingsThe elongation of bearings impacts the positioning accuracy and repeatability of the feed drive system and of CNC machines. Next, an analytical model for the rigorous assessment of CNC feed drive system has been designed and developed. The positioning accuracy of CNC machine in relation with different pre-loading values has been analyzed.Practical implicationsThe results obtained from these investigations enhance the positioning accuracy of CNC machining centers. The optimum pre-loading value has been analyzed among the available ranges, and it has been proposed that optimal results have been achieved at 5 per cent of dynamic load rating.Originality/valueThis paper proposes improved explorations toward the performance of the CNC machines by optimizing the positioning accuracy through pre-loading. Finally, analytical estimations have been carried out to prove the validity of the proposal.

Mucoepidermal carcinoma (MEC) is a tumour having mixed components of mucus secreting and epidermoid cells. Salivary glands are the the most common site of origin. Primary cutaneous MEC is a rare presentation. We report a primary cutaneous MEC in a 98-year-old woman presenting a noduloulcerative lesion over the dorsum of the nose. Histopathology of the tumour showed nests of epidermoid cells with glandular differentiation and mucin production. The diagnosis was confirmed by immunohistochemistry.

Primary cutaneous amyloidosis (PCA) is the deposition of amyloid proteins in the skin without systemic involvement. Amyloidosis cutis dyschromica (ACD) is a rare variant of PCA with onset typically in early childhood or at a prepubertal age. It is more common in the Asian and Southeast Asian people. Clinically it manifests as asymptomatic diffuse hyperpigmentation interspersed with hypopigmented spots without papulation. Histologically, small foci of amyloid closely under the epidermis are seen. There are only few case reports in the literature of this rarer variant. We report a case of a 32-year-old male presenting as dyschromatosis with a prepubertal onset and histopathological evidence of intradermal deposits in the upper dermis which was confirmed on Congo red staining and hence was diagnosed as a case of ACD.

Polyphylla sikkimensis is an important pest of subfamily Melolonthinae and tribe Melolonthini. The adults of this species are defoliators and grubs are root feeders. Understanding the life history and identification characters of P. sikkimensis is, therefore, essential for developing effective management strategies. Polyphylla sikkimensis has a biennial life cycle with average duration of egg, larva, pre-pupa, and pupa as 17.2, 583.7, 19.3 and 18.6 days, respectively. Polyphylla sikkimensis completes one generation in 619–652 days in laboratory. Adult longevity averages 15.1 days for males and 21.5 days for females. The fully fed first, second and third instar grubs measure 10.16–13.97, 23.65–27.70 and 48.33–54.17 mm in length and 2.60–2.84, 4.33–5.13 and 7.92–8.48 mm in head capsule width. The body length of pupa and pre-pupa was recorded as 33.33–38.32 and 30.92–34.10 mm, respectively. A detailed description of larval and adult characters was generated. The larvae of P. sikkimensis can easily be distinguished based on mandibles, epipharynx, raster pattern and shape of anal opening. The caudal extremity of pupae also allows differentiation of P. sikkimensis from other species. Shape and size of antennae, pronotum and pygidium can be used to separate sexes of P. sikkimensis and to distinguish this species from others. Male genitalia is the most stable character for differentiation of species in adult stage.

Melolontha is an important genus of the subfamily Melolonthinae and the tribe Melolonthini. It is a major polyphagous pest of different agricultural crops and forest trees. The adults of this species are defoliators and grubs are root feeders. It is essential to acquire a better understanding of the correct identity of these species to implement the most suitable pest management options. In this study, three Melolontha species viz., Melolontha cuprescens, Melolontha furcicauda and Melolontha indica were investigated using light microscopy, in order to generate detailed information on morphological characters for the pest identification. A detailed comparative description of the larval characters (mouthparts, raster, spiracles and thoracic legs); pupal characters (antennae and caudal appendages); adult characters (antennae, pronotum, scutellum, meso-metasternal process, legs, pygidium and male genitalia) is given with the help of suitable microscopic pictures and line diagrams. The larvae of these species can easily be distinguished based on mandibles, epipharynx, raster pattern and shape of anal opening. The caudal extremity of pupae also allows differentiation among Melolontha species. In beetles, shape and size of antennae, pronotum and pygidium can be used to separate sexes and to differentiate Melolontha species. Male genitalia is the most stable character for differentiation of species in the adult stage.

We have studied the effect of hydrothermal conditions at constant temperature of 180 °C, varying preparation time for 15, 30 and 45 h on nanostructures of diluted magnetic semiconductor Sn 0.95 Co 0.05 O 2 (SC5). X-ray diffraction pattern confirm the tetragonal SnO 2 rutile phase. The transmission and scanning electron microscopy shows the resulting nanostructures i.e. nanospheres and nanorods. The proposed reaction mechanism is given. The Raman spectra show the formation of tetragonal rutile structure of SC5 nanostructures. Fourier transform infrared spectrum has been used to verify the existence of Sn–O bond. The photoluminescence spectra show that the emission spectral intensity increases gradually with decreasing grains size, increasing hydrothermal heating time of SC5 samples and exhibits an intense blue luminescence centered at a wavelength of 531 nm. The optical absorbance measurements revealed that the nanometric size of the materials influences the energy band gap. All the prepared SC5 samples exhibit room temperature ferromagnetism.

Plant Simulation software enables the simulation and optimization of production systems and processes. Using Plant Simulation, you can optimize material flow, resource utilization and logistics for all levels of plant planning from global production facilities, through local plants, to specific lines. In times of increasing cost and time pressures in production, along with ongoing globalization, logistics has become a key factor in the success of a company. The need to deliver JIT (just-in-time)/ JIS (just-in-sequence), introduce Kanban, plan and build new production lines and manage global production networks (to name a few) requires objective decision criteria to help management evaluate and compare alternative approaches. Plant Simulation helps create digital models of logistic systems (e.g., production) to explore the systems' characteristics and to optimize their performance. The digital model enables users to run experiments and what-if scenarios without disturbing an existing production system or - when used in the planning process - long before the real system is installed. Extensive analysis tools, statistics and charts let users evaluate different manufacturing scenarios and make fast, reliable decisions in the early stages of production planning. Plant Simulation helps users to Detect and eliminate problems that otherwise would require cost- and time consuming correction measures during production ramp up Minimize the investment cost of production lines without jeopardizing required output, Optimize the performance of existing production systems by taking measures that have been verified in a simulation environment prior to implementation.