Freezing of viable embryos and larvae of marine shrimp, Penaeus semisulcatus de Haan

Although sperm cryopreservation has been carried out successfully in a number of commercially important aquatic species, particularly in some teleost fish (see review of Rana in Muir & Roberts 1993) and also shellfish (Subramoniam 1993), the technology is still not at the stage of advanced commercial application that is seen in domestic mammals. Cryopreservation of eggs and embryos, of aquatic animals however, is a virgin field in cryobiology and has not yet received any appreciable amount of attention. The first successful attempt at the cryopreservation of embryos of sea urchin was reported by Asahina & Takahashi (1978). Later Zell (1978) and Erdahl & Graham (1980) have reported preliminary attempts to freeze the eggs of rainbow trout

Implementation of Fault-tolerant Quantum Logic Gates via Optimal Control

The implementation of fault-tolerant quantum gates on encoded logic qubits is considered. It is shown that transversal implementation of logic gates based on simple geometric control ideas is problematic for realistic physical systems suffering from imperfections such as qubit inhomogeneity or uncontrollable interactions between qubits. However, this problem can be overcome by formulating the task as an optimal control problem and designing efficient algorithms to solve it. In particular, we can find solutions that implement all of the elementary logic gates in a fixed amount of time with limited control resources for the five-qubit stabilizer code. Most importantly, logic gates that are extremely difficult to implement using conventional techniques even for ideal systems, such as the T-gate for the five-qubit stabilizer code, do not appear to pose a problem for optimal control.Comment: 18 pages, ioptex, many figure

Prospects of Grouper Culture in India

The "Groupers" of the genus Epinephelus are excellent marine food fishes in the Indo Pacific and Carribean regions and have assumed importance for commercial culture in recent year

Stormwater sand filters in water-sensitive urban design

This paper investigates the suitability of sand filters for harvesting and treating stormwater for non-potable reuse purposes. A stormwater sand filtration device was constructed in a small urban catchment in Sydney, Australia. A sand filter is typically used in water-sensitive urban design (WSUD) as a component of a treatment train to remove pollution from stormwater before discharge to receiving waters, to groundwater or for collection and reuse. This paper describes an 18 month field study undertaken to determine the effectiveness and pollutant removal efficiency of a sand filter, and the differences in the pollutant removal efficiency of two grades of sand. A comparison of pollutant removal with previous literature on sand filters showed similar efficiencies but nutrient removal was higher than expected. A further unexpected result was that the coarse filter media performed as well as the fine media for most pollutant types and was superior in suspended solids removal. Improved modelling equations for predicting suspended solids and total phosphorus removal in sand filters are also presented in this paper

Indian experience of large scale cultured marine pearl production using Pinctada fucata (Gould) from southeast coast of India: A critical review

In India, research on marine pearl culture was started in 1972 and the first cultured marine pearl from Pinctada fucata was rolled out a year later through the earnest efforts of Central Marine Fisheries Research Institute, Kochi (CMFRI) at its Tuticorin Research Centre. Subsequently, improvements of the technology were made by various scientists involved at different centres of CMFRI focussing on different issues of marine pearl culture. Information on different aspects of marine pearl culture such as surveys for stock position, ecology of pearl beds, small scale experimental culture of mother oysters, surgical nucleation and spherical pearl and designer pearl production (‘mabe’) has already been published in various sources including few instances of technology transfers to entrepreneurs/fisher folk. Though, the experimental results were encouraging, anticipated technology transfer did not take place subsequently. Hence a large scale marine pearl culture demonstration was carried out and viability of the technology was redemonstrated at the Regional centre of CMFRI, Mandapam Camp during 1997 - 2003 through an ICAR Revolving Fund Project which resulted in wealth of information regarding different aspects of marine pearl culture. In the present account, the lessons learnt based on the published information as well as the data (unpublished) obtained in the large scale culture are analysed and classified under the critical activities of pearl culture and presented in the form of a ‘non systematic critical review’ essentially to arrive at the status of marine pearl culture in India

Multi-serotype pneumococcal nasopharyngeal carriage prevalence in vaccine naïve Nepalese children, assessed using molecular serotyping.

Invasive pneumococcal disease is one of the major causes of death in young children in resource poor countries. Nasopharyngeal carriage studies provide insight into the local prevalence of circulating pneumococcal serotypes. There are very few data on the concurrent carriage of multiple pneumococcal serotypes. This study aimed to identify the prevalence and serotype distribution of pneumococci carried in the nasopharynx of young healthy Nepalese children prior to the introduction of a pneumococcal conjugate vaccine using a microarray-based molecular serotyping method capable of detecting multi-serotype carriage. We conducted a cross-sectional study of healthy children aged 6 weeks to 24 months from the Kathmandu Valley, Nepal between May and October 2012. Nasopharyngeal swabs were frozen and subsequently plated on selective culture media. DNA extracts of plate sweeps of pneumococcal colonies from these cultures were analysed using a molecular serotyping microarray capable of detecting relative abundance of multiple pneumococcal serotypes. 600 children were enrolled into the study: 199 aged 6 weeks to <6 months, 202 aged 6 months to < 12 months, and 199 aged 12 month to 24 months. Typeable pneumococci were identified in 297/600 (49.5%) of samples with more than one serotype being found in 67/297 (20.2%) of these samples. The serotypes covered by the thirteen-valent pneumococcal conjugate vaccine were identified in 44.4% of samples containing typeable pneumococci. Application of a molecular serotyping approach to identification of multiple pneumococcal carriage demonstrates a substantial prevalence of co-colonisation. Continued surveillance utilising this approach following the introduction of routine use of pneumococcal conjugate vaccinates in infants will provide a more accurate understanding of vaccine efficacy against carriage and a better understanding of the dynamics of subsequent serotype and genotype replacement

Formation of lead lanthanum zirconate titanate films by heat treatments

Lead lanthanum zirconate titanate (PLZT) also called lanthanum doped PZT films were deposited by RF magnetron sputtering. PLZT in the perovskite phase is required to obtain a film with a large electro-optic effect. It can also be used as a ferroelectric and piezoelectric material. However films that have not been heat treated either during or after deposition are typically in the pyrochlore phase. Perovskite PLZT films obtained by heating the substrate during sputtering showed little evidence of cracks in the films sputtered without heating the substrate were not in the Perovskite phase and post deposition annealing was required to do so. Both furnace and rapid thermal annealing were investigated but in both cases cracks formed in the films to various degrees. Such films are unsuitable for optical device fabrication. To determine the orientation of PLZT films X-ray diffraction (XRD) spectras were obtained and compared. Samples were prepared on silicon substrates which had a thin film of 20 nm Ti/100 nm Pt deposited by electron beam evaporation. Sputtering was done in an argon atmosphere using a PLZT (9/65/35) target. Thicknesses of 1 mum were obtained. Some samples were heated during sputtering up to a temperature of 650 degC. Annealing temperatures were varied from 500 to 750 degC. The best results (determined by XRD) were obtained for RTA at 750 degC for 10 minutes in air. XRD spectra of before and after annealing show a significant increase in the Perovskite peaks. The patterning of these films to form optical waveguides by ion beam etching is also presented. The samples were patterned with photoresist masks and ion beam etched using argon at a gun voltage of 500

Chemical-assisted physico-biological water mining system

Water mining is the process of extracting valuable water from a sewerage network by treating raw sewage to high standards. A range of commercially viable water mining treatment technologies are now available to treat sewage to specified water quality targets. Most of these technologies have minimal plant footprint requirements, making them suitable for decentralised operations. This paper discusses a hybrid water mining system that includes chemically assisted fine solids separation followed by a biological treatment process. Results from the first proof testing of this water mining system in Sydney, Australia are presented. The results confirm the suitability of the hybrid system for producing high-quality water for non-potable reuse

Socio-hydrologic drivers of the pendulum swing between agricultural development and environmental health: A case study from Murrumbidgee River basin, Australia

This paper presents a case study centred on the Murrumbidgee River basin in eastern Australia. It illustrates the dynamics of the balance between water extraction and use for food production, and efforts to mitigate and reverse consequent degradation of the riparian environment. In particular, the paper traces the history of a pendulum swing between an exclusive focus on agricultural development and food production in the initial stages and its attendant socio-economic benefits, followed by the gradual realization of the adverse environmental impacts, subsequent efforts to mitigate these with the use of remedial measures, and ultimately concerted efforts and externally imposed solutions to restore environmental health and ecosystem services. The 100-year history of development within the Murrumbidgee is divided into four eras, each underpinned by the dominance of different values and norms and turning points characterized by their changes. The various stages of development can be characterized by the dominance, in turn, of infrastructure systems, policy frameworks, economic instruments, and technological solutions. The paper argues that, to avoid these costly pendulum swings, management needs to be underpinned by long-term coupled socio-hydrologic system models that explicitly include the two-way coupling between human and hydrological systems, including the slow evolution of human values and norms relating to water and the environment. Such coupled human-water system models can provide insights into dominant controls of the trajectory of their co-evolution in a given system, and can also be used to interpret patterns of co-evolution of such coupled systems in different places across gradients of climatic, socio-economic and socio-cultural conditions, and in this way to help develop generalizable understanding. © 2014 Author(s)