This research was focused on the thermoluminescence (TL) response of commercially produced single-mode telecommunication optical fibre manufactured by INOCORP (Canada). The fibres were either in the form of pure silica (SiO2) or as SiO2 doped with Ge or Al at concentrations appropriate for total internal reflection, as required for telecommunication purposes. Each of these INOCORP fibres had a core diameter of 125 ± 0.1 μm. It was noted that dopant concentration was not included among the data provided in the accompanying product data sheet. A particularly important parameter for obtaining the highest TL yield in this study was the dopant concentration of the SiO2 fibre. The dopants tended to diffuse during the production of the optical fibre. To obtain this parameter, proton induced X-ray emission (PIXE) analysis was utilised. PIXE while having limited depth resolution could unambiguously identify elements and analyse trace elements with a detection limit approaching μg g–1. For Al-doped fibres, dopant concentrations in the range of 0.98 – 2.93 mol% had been estimated, the equivalent range for Ge-doped fibres was 0.53 – 0.71 mol%. A linear dose response was observed following 2.5 MeV proton irradiation for Ge- and Al-doped fibres for up to 7 min exposure.
The leafhopper genus Dusuna Distant is revised to include seven species including one new species D. anacantha sp. nov. from China and one new combination D. distanti (Schmidt) n. comb. All species are described and illustrated. A checklist to species of the genus is provided together with a key to separate the two species known from the male. Figures of an unknown species from Malaysia (possibly new) are also included.
One new genus of the tribe Ledrini, Yelahanka gen. nov. is described with Petalocephala granulosa Distant as its type species. The genus is characterised by the flexing of the forewing laterad of a strongly carinate or keeled outer claval vein and the claval veins fused in the distal two thirds. Seven new species, Yelahanka canaraica sp. nov. (India: Karnataka), Y. kodaiensis sp. nov. (India: Tamil Nadu), Y. montana sp. nov. (India: Tamil Nadu), Y. nepalica sp. nov. (Nepal), Y. sikkimensis sp. nov. (India: Sikkim), Y. shillongensis sp. nov. (India: Meghalaya) and Y. trifida sp. nov. (India: Himachal Pradesh, Arunachal Pradesh) are described and illustrated. The following new combinations are proposed: Yelahanka bainbriggei (Distant) comb. nov., Y. granulosa (Distant) comb. nov., Y. punctata (Walker) comb. nov. and Y. tabulata (Distant) comb. nov.; originally punctata was placed in the genus Ledra Fabricius and remaining species were placed in Petalocephala Stål. Petalocephala bainbriggei Distant 1916 is treated as a junior synonym of Y. granulosa (Distant 1910) syn. nov. and P. tabulata Distant 1908 is treated as a junior synonym of Yelahanka punctata (Walker 1851) syn. nov. Y. granulosa is newly recorded from Africa (Tanzania and Kenya) and Malaya. Relationships of the new genus with other genera of Ledrini are discussed and a key to species of the genus is also provided.
Modern linear accelerators, the predominant teletherapy machine in major radiotherapy centres worldwide, provide multiple electron and photon beam energies. To obtain reasonable treatment times, intense electron beam currents are achievable. In association with this capability, there is considerable demand to validate patient dose using systems of dosimetry offering characteristics that include good spatial resolution, high precision and accuracy. Present interest is in the thermoluminescence response and dosimetric utility of commercially available doped optical fibres. The important parameter for obtaining the highest TL yield during this study is to know the dopant concentration of the SiO2 fibre because during the production of the optical fibres, the dopants tend to diffuse. To achieve this aim, proton-induced X-ray emission (PIXE), which has no depth resolution but can unambiguously identify elements and analyse for trace elements with detection limits approaching microg/g, was used. For Al-doped fibres, the dopant concentration in the range 0.98-2.93 mol% have been estimated, with equivalent range for Ge-doped fibres being 0.53-0.71 mol%. In making central-axis irradiation measurements a solid water phantom was used. For 6-MV photons and electron energies in the range 6, 9 and 12 MeV, a source to surface distance of 100 cm was used, with a dose rate of 400 cGy/min for photons and electrons. The TL measurements show a linear dose-response over the delivered range of absorbed dose from 1 to 4 Gy. Fading was found to be minimal, less than 10% over five days subsequent to irradiation. The minimum detectable dose for 6-MV photons was found to be 4, 30 and 900 microGy for TLD-100 chips, Ge- and Al-doped fibres, respectively. For 6-, 9- and 12-MeV electron energies, the minimum detectable dose were in the range 3-5, 30-50 and 800-1400 microGy for TLD-100 chip, Ge-doped and Al-doped fibres, respectively.
Two new genera, Malaysiapona gen. nov. and Chandrapona gen. nov. of Paraboloponina leafhoppers (Cicadellidae: Deltocephalinae: Drabescini) with their unusally developed aedeagal base are described from the Pacific (Malaysia). The following new species are also described with the new genera: Malaysiapona brevipenis sp. nov. from Sabah, M. filamenta sp. nov., from Sarawak and Chandrapona vespertilis sp. nov. from Sabah.
Many researchers have noted that media coverage of drugs can be sensationalized and/or have questionable accuracy. Additionally, it has been alleged that the media often treats all drugs as harmful and can fail to differentiate between different types of drugs. Within this context, the researchers sought to deconstruct how media coverage was similar and/or different according to drug type within a national media outlet in Malaysia. Our sample comprised 487 news articles published over a two-year period. Articles were coded to reflect thematic differences in drug framing. We focus on five drugs widely used in Malaysia (amphetamines, opiates, cannabis, cocaine, and kratom) and assess the most frequent themes, crimes, and locations mentioned in reference to each drug. All drugs were primarily covered in a criminal justice context, and articles highlighted concern about the spread of these drugs and their abuse. Drug coverage varied, particularly in association with violent crimes, specific regions, and discussion of legality. We find evidence of both similarities and differences in how drugs were covered. Variation in coverage demonstrated that certain drugs were deemed a heightened threat, as well as reflected broader social/political processes shaping ongoing debates over treatment approaches and legality.