Type designation of five Lindley’s names in the Genus Habenaria (Orchidaceae)

The present study highlights the type designation on 5 species of the genus Habenaria Willd. (Orchidaceae) namely H. cephalotes Lindl., H. heyneana Lindl., H. longicornu Lindl., H. macrostachya Lindl. and H. plantaginea Lindl

Quasiperpendicular high Mach number Shocks

Shock waves exist throughout the universe and are fundamental to understanding the nature of collisionless plasmas. Reformation is a process, driven by microphysics, which typically occurs at high Mach number supercritical shocks. While ongoing studies have investigated this process extensively both theoretically and via simulations, their observations remain few and far between. In this letter we present a study of very high Mach number shocks in a parameter space that has been poorly explored and we identify reformation using in situ magnetic field observations from the Cassini spacecraft at 10 AU. This has given us an insight into quasi-perpendicular shocks across two orders of magnitude in Alfven Mach number (MA) which could potentially bridge the gap between modest terrestrial shocks and more exotic astrophysical shocks. For the first time, we show evidence for cyclic reformation controlled by specular ion reflection occurring at the predicted timescale of ~0.3 {\tau}c, where {\tau}c is the ion gyroperiod. In addition, we experimentally reveal the relationship between reformation and MA and focus on the magnetic structure of such shocks to further show that for the same MA, a reforming shock exhibits stronger magnetic field amplification than a shock that is not reforming.Comment: Accepted and Published in Physical Review Letters (2015

Taxonomic notes on two endemic species of Oberonia Lindl. from Western Ghats, India

The genus Oberonia is known for its micro floral arrangement. Due to its minute structure, excess of new species are reported. The present paper reveals the synonymization of two recently described species of the genus Oberonia viz. O. saintberchmansii and O. wynadensis under O. anamalayana and O. josephi respectively. The original illustration and live dissected images of the species are provided for easy identification

Eco-hydromorphic Classification for Understanding Stream Macroinvertebrate Biodiversity in Brunei Darussalam, Northern Borneo

This is the final version. Available from Academia Sinica via the DOI in this record.Linking ecology with river geomorphology and hydrology (geomorphic and hydraulic template) plays an important role in the study of macroinvertebrate biodiversity. This understanding and knowledge is crucial in implementing sensible conservation management for ecosystem health monitoring. However, most macroinvertebrate research has been conducted in temperate ecosystems. This study examines the eco-hydrogeomorphology and macroinvertebrate biodiversity of two remote tropical streams in northern Borneo (Bukit Pagon catchment, Brunei Darussalam’s highest mountain - 1850 m) using temperate classification models, more specifically, biotopes. Fast flowing biotopes were defined as bedrock runs and cobble riffles whilst the slow flowing biotopes were deposition pools. Macroinvertebrate size structure associated with biotopes, which can influence overall ecological processes, was also investigated. Forty-three macroinvertebrate taxa were recorded during the study; biodiversity was similar between the study streams. There were differences among biotopes with the lowest diversity occurring in fast flowing biotopes (p = 0.05*). Community structure also varied among the biotopes. Cluster analysis of macroinvertebrate abundance revealed an 0.8 dissimilarity between the fast and slow biotopes. Several taxa were found in multiple biotopes, which is likely linked to the occurrence of moss and leaf litter. Macroinvertebrate size structure distribution between the fast and slow biotopes was statistically different. Our findings suggest biotopes may be an appropriate scale to investigate macroinvertebrate biodiversity in tropical streams. Specifically, we found that biotopes had different macroinvertebrate communities and richness. Further research is required to understand the importance of habitat parameters that are not directly related to flow velocities such as moss. These habitats are important as places of refuge, allowing colonisation that would otherwise be inhospitable during flood periods.University of Brunei DarussalamThe International Consortium of Universities for the Study of Biodiversity and the Environment (iCUBE

Suprathermal electrons at Saturn's bow shock

The leading explanation for the origin of galactic cosmic rays is particle acceleration at the shocks surrounding young supernova remnants (SNRs), although crucial aspects of the acceleration process are unclear. The similar collisionless plasma shocks frequently encountered by spacecraft in the solar wind are generally far weaker (lower Mach number) than these SNR shocks. However, the Cassini spacecraft has shown that the shock standing in the solar wind sunward of Saturn (Saturn's bow shock) can occasionally reach this high-Mach number astrophysical regime. In this regime Cassini has provided the first in situ evidence for electron acceleration under quasi-parallel upstream magnetic conditions. Here we present the full picture of suprathermal electrons at Saturn's bow shock revealed by Cassini. The downstream thermal electron distribution is resolved in all data taken by the low-energy electron detector (CAPS-ELS, <28 keV) during shock crossings, but the higher energy channels were at (or close to) background. The high-energy electron detector (MIMI-LEMMS, >18 keV) measured a suprathermal electron signature at 31 of 508 crossings, where typically only the lowest energy channels (<100 keV) were above background. We show that these results are consistent with theory in which the "injection" of thermal electrons into an acceleration process involves interaction with whistler waves at the shock front, and becomes possible for all upstream magnetic field orientations at high Mach numbers like those of the strong shocks around young SNRs. A future dedicated study will analyze the rare crossings with evidence for relativistic electrons (up to ~1 MeV).Comment: 22 pages, 5 figures. Accepted for publication in Ap

An investigation of the effectiveness of PBL online on students’ creative thinking: a case study in Malaysia

In this paper we scrutinized the effectiveness of combining the Problem-Based Learning (PBL) approach and Online Learning medium in improving students’ creative thinking particularly amongst physics students. A cohort of 61 science undergraduate physics students from the School of Science and Technology (SST), and 41 pre-service physics teachers from the School of Education and Social Development (SESD) of the University Malaysia Sabah comprised the sample. The sample was broken up into experimental and control groups, with the experimental group experiencing the PBL and online learning activities, and the control group more traditional learning conducts. Both groups were supported via an online learning environment, which acted as the main medium for learning. Participants’ creativity was evaluated using a previously validated instrument, the Torrance Test of Creativity Thinking (TTCT) administered before (pre-test) and after (post-test) the intervention. Examination of these data, points to statistically significant differences between the traditional and PBL groups in creative thinking. Thus the research findings suggest that PBL and Online learning are capable in improving physics students’ and pre-service science teachers’ creative thinking effectively