University of Malaya

About: University of Malaya is a education organization based out in Kuala Lumpur, Malaysia. It is known for research contribution in the topics: Population & Fiber laser. The organization has 25087 authors who have published 51491 publications receiving 1036791 citations. The organization is also known as: UM & Universiti Malaya.

Towards a natural classification of Botryosphaeriales

Abstract: The type specimens of Auerswaldia, Auerswaldiella, Barriopsis, Botryosphaeria, Leptoguignardia, Melanops, Neodeightonia, Phaeobotryon, Phaeobotryosphaeria, Phyllachorella, Pyrenostigme, Saccharata, Sivanesania, Spencermartinsia and Vestergrenia were examined and fresh specimens of Botryosphaeriales were collected from Thailand. This material is used to provide a systematic treatment of Botryosphaeriales based on morphology and phylogeny. Two new genera, Botryobambusa and Cophinforma are introduced and compared with existing genera. Four species new to science, Auerswaldia dothiorella, A. lignicola, Botryosphaeria fusispora and Phaeobotryosphaeria eucalypti, are also described and justified. We accept 29 genera in Botryosphaeriales, with Macrovalsaria being newly placed. In the phylogenetic tree, the 114 strains of Botyrosphaeriales included in the analysis cluster into two major clades with 80 %, 96 % and 1.00 (MP, ML and BY) support, with Clade A containing the family type of Botryosphaeriaceae, and Clade B containing Phyllosticta, Saccharata and Melanops species. This group may represent Phyllostictaceae. In Clade A the taxa analyzed cluster in eight sub-clades (Clades A1–8). Clade A1 comprises three distinct subclusters corresponding to the genera Diplodia (Diplodia Clade), Neodeightonia (Neodeightonia Clade) and Lasiodiplodia (Lasiodiplodia Clade). Clade A2 clusters into three groups representing Phaeobotryosphaeria (100 %), Phaeobotryon (100 %) and Barriopsis (94 %). Clade A3 incorporates 17 strains that cluster into three well-supported genera (Dothiorella (86 %), Spencermartinsia (100 %) and Auerswaldia (63 %); the position of Macrophomina is not stable. Clade A4 is a single lineage (100 %) representing the new genus Botryobambusa. Clade A5 is a well-supported subclade incorporating Neofussicoccum. Clade A6 represents the type species of Botryosphaeria, three other Botryosphaeria species and two other genera, Neoscytalidium and Cophinforma gen. nov. Clade A7 comprises two Pseudofusicoccum species and Clade A8 has two Aplosporella species. These sub-clades may eventually require separate families but this requires analysis of a much larger dataset. Our data advances the understanding of Botryosphaeriales, there is, however, still much research to be carried out with resolution of families and genera, linkage of sexual and asexual morphs and differentiation of cryptic species.

Single phase transformerless inverter topologies for grid-tied photovoltaic system: A review

Abstract: Grid-tied inverters are the key components of distributed generation system because of their function as an effective interface between renewable energy sources and utility. Recently, there has been an increasing interest in the use of transformerless inverter for low-voltage single-phase grid-tied photovoltaic (PV) system due to higher efficiency, lower cost, smaller size and weight when compared to the ones with transformer. However, the leakage current issues of transformerless inverter, which depends on the topology structure and modulation scheme, have to be addressed very carefully. This review focuses on the transformerless topologies, which are classified into three basic groups based on the decoupling method and leakage current characteristics. Different topologies under the three classes are presented, compared and evaluated based on leakage current, component ratings, advantages, and disadvantages. An examination of demand for the inverter, the utility grid, and the PV module are presented. A performance comparison in MATLAB/Simulink environment is done among different topologies. Also an analysis has been presented to select a better topology. Finally, based on the analysis and simulation results, a comparison table has been presented. Furthermore, some important experimental parameters have been summarized.

The Role of Edge Computing in Internet of Things

Abstract: Remarkable advancements in embedded systems- on-a-chip have significantly increased the number of commercial devices that possess sufficient resources to run full-fledged operating systems. This change has extended the potential of the IoT. Many early IoT devices could only collect and send data for analysis. However, the increasing computing capacity of today's devices allow them to perform complex computations on-site, resulting in edge computing. Edge computing extends cloud computing capabilities by bringing services close to the edge of a network and thus supports a new variety of services and applications. In this work, we investigate, highlight, and report on recent advances in edge computing technologies with respect to measuring their impact on IoT. We establish a taxonomy of edge computing by classifying and categorizing existing literature, and by doing so, we reveal the salient and supportive features of different edge computing paradigms for IoT. Moreover, we present the key requirements for the successful deployment of edge computing in IoT and discuss a few indispensable scenarios of edge computing in IoT. Several open research challenges are also outlined.

Proposed categorization of pathological states of EBV-associated T/natural killer-cell lymphoproliferative disorder (LPD) in children and young adults: Overlap with chronic active EBV infection and infantile fulminant EBV T-LPD

Abstract: EBV-associated T/natural killer (NK)-cell lymphoproliferative disorder (EBV-T/NK LPD) of children and young adults is generally referred to with the blanket nosological term of severe chronic active EBV infection (CAEBV). This disease is rare, associated with high morbidity and mortality, and appears to be more prevalent in East Asian countries. But because there is no grading or categorization system for CAEBV, pathologists and clinicians often disagree regarding diagnosis and therapy. EBV-T/NK LPD includes polyclonal, oligoclonal, and monoclonal proliferation of cytotoxic T and/or NK cells. Moreover, a unique disease previously described as infantile fulminant EBV-associated T-LPD has been identified and overlaps with EBV-T/NK LPD. In the present review a clinicopathological categorization of EBV-T/NK LPD is proposed, based on pathological evaluation and molecular data, as follows: (i) category A1, polymorphic LPD without clonal proliferation of EBV-infected cells; (ii) category A2, polymorphic LPD with clonality; (iii) category A3, monomorphic LPD (T-cell or NK cell lymphoma/leukemia) with clonality; and (iv) category B, monomorphic LPD (T-cell lymphoma) with clonality and fulminant course. Categories A1, A2, and A3 possibly constitute a continuous spectrum and together are equivalent to CAEBV. Category B is the exact equivalent of infantile fulminant EBV-associated T-LPD. It is expected that this categorization system will provide a guide for the better understanding of this disorder. This proposal was approved at the third meeting of the Asian Hematopathology Association (Nagoya, 2006).

A review of Safety, Health and Environmental (SHE) issues of solar energy system

Abstract: Solar energy is one of the cleanest forms of energy sources and considered as a green source of energy. Solar energy benefit ranges from low carbon emission, no fossil fuel requirement, long term solar resources, less payback time and other. However like other power generation sources, solar energy has also some Safety, Health and Environmental (SHE) concerns. This paper presents the overview of solar energy technologies and addresses the SHE impact of solar energy technologies to the sustainability of human activities. This paper will also recommend the possible ways to reduce the effect of potential hazards of widespread use of solar energy technologies.