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Of several dozen galaxies observed spectroscopically that are candidates for having a redshift (z) in excess of seven, only five have had their redshifts confirmed via Lyman a emission, at z = 7.008,7.045, 7.109, 7.213 and 7.215 (refs 1-4). The small fraction of confirmed galaxies may indicate that the neutral fraction in the intergalactic medium rises quickly at z > 6.5, given that Lyman a is resonantly scattered by neutral gas (3,5-8). The small samples and limited depth of previous observations, however, makes these conclusions tentative. Here we report a deep near-infrared spectroscopic survey of 43 photometrically-selected galaxies with z > 6.5. We detect a near-infrared emission line from only a single galaxy, confirming that some process is making Lyman a difficult to detect. The detected emission line at a wavelength of 1.0343 micrometres is likely to be Lyman α emission, placing this galaxy at a redshift z= 7.51, an epoch 700 million years after the Big Bang. This galaxy's colours are consistent with significant metal content, implying that galaxies become enriched rapidly. We calculate a surprisingly high star-formation rate of about 330 solar masses per year, which is more than a factor of 100 greater than that seen in the Milky Way. Such a galaxy is unexpected in a survey of our size (9), suggesting that the early Universe may harbour a larger number of intense sites of star formation than expected., We obtained near-infrared (NIR) spectroscopy of galaxies originally discovered in the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) (10,11) with the newly commissioned NIR spectrograph MOSFIRE (12) on the [...]

Problem statement: Molecular methods have been used to detect phytoplasma in Malayan Red Dwarf (MRD) ecotype of coconut for the first time in Malaysia. Detect phytoplasma from coconut showing yellowing symptoms by nested PCR and Classify phytoplasma associated with disease of coconut palms, based on analysis of 16S rRNA gene operon sequences and virtual RFLP. Approach: Twenty MRD symptomatic palms were tested. Leaf spear, inflorescence and wood shavings from trunks of coconut palms showing yellowing symptoms were harvested from Serdang located in Selangor state. PCR assays and sequence analysis were carried out. Results: Nested PCR with primer pairs R16F2n/R16R2 and fU5/rU3 resulted in amplification of products of approximately 1.2 kb and 890 bp respectively, from 8 out of 20 MRD symptomatic palms tested. Sequence analysis of the 16S rDNA PCR products determined that the phytoplasma strain associated with Coconut Yellow Decline (CYD) in MRD ecotype belongs to the 'Candidatus Phytoplasma cynodontis' (16SrXIV) group of phytoplasmas. In addition, nested R16F2n/R16R2 PCR products from 6 spear leaves and 2 inflorescences from MRD palms showed high sequence similarity to the 16S rRNA gene from coconut chloroplasts, with a similar size (approximately 1.3 kb) and a further 5 R16F2n/R16R2 PCR products from MRD inflorescences showed high sequence similarities to Bacillus spp. 16S rRNA gene sequences. Conclusion: These results indicate that sequencing is a reliable method for the detection. Furthermore, trunk borings are the most reliable source of DNA for phytoplasma detection in coconuts using 16S rRNA gene primers, since there is less co-amplification of PCR products from other organisms when compared to spear leaves and inflorescences, nor from the spear leaves and inflorescences of MRD palms when primers fU5/rU3 were used in nested PCR. Key words: Coconut palm, phytoplasma, nested PCR, cloning, sequencing, INTRODUCTION Coconut palm (Cocos nucifera L.) is a versatile tree, popularly know as 'King of Palms' and 'Kalpavriksha', which translates as 'tree that gives all that is necessary for living.' [...]

Byline: D.E. Biskri (Department of Automated Production Engineering, Ecole de technologie superieure, 1100 Notre Dame West, Montreal, Quebec, H3C 1K3, Canada, ruxandra@gpa.etsmtl.ca); R.M. Botez (Department of Automated Production Engineering, Ecole [...]

Byline: P. Armstrong (1), P. M. Chadwick (1), P. J. Cottle (1), J. E. Dickinson (1), M. R. Dickinson (1), N. A. Dipper (1), S. E. Hilton (1), W. Hogg (1), J. Holder (1), T. R. Kendall (1), T. J. L. McComb (1), C. M. Moore (1), K. J. Orford (1), S. M. Rayner (1), I. D. Roberts (1), M. D. Roberts (1), M. Robertshaw (1), S. E. Shaw (1), K. Tindale (1), S. P. Tummey (1), K. E. Turver (1) Keywords: atmospheric; Cerenk technique; gamma ray astronomy; gamma ray telescopes Abstract: The design, construction and operation of the University of Durham ground-based gamma ray telescope is discussed. The telescope has been designed to detect gamma rays in the a$? 200 GeV region and to achieve good discrimination between gamma ray and hadron initiated showers in the higher energy region (a3 300 GeV). The telescope was commissioned in 1995 and a description of its design and operation is presented, together with a verification of the telescope's performance. Author Affiliation: (1) Department of Physics, University of Durham, South Road, Rochester Building, Science Laboratories, Durham, DH1 3LE, U.K Article History: Registration Date: 02/10/2004

Byline: M.M.A. Khalfan, A.S. Oyegoke, P. McDermott, M. Dickinson The overall aim of the study is to examine the problems associated with the prevalent procurement routes, subsequent changes in supply chain management and introduction of alternative procurement routes which are innovative and agile in their nature. The trend in the UK seems to favour an integrated supply chain from the outset of a project, resulting into a transition from rigidity to agility within the development process. Client's role within the whole process is quite crucial and this paper shows the practical contribution of public sector clients in initiating as well as implementing innovative procurement routes that integrates the supply chain. The study is conducted via extensive literature review covering policy documents and a case study. The paper presents the techniques used by the public clients such as aggregation of demand to get aggregated supply result in agility and integration among supply chain participants and subcontractors along side the main contractors. The paper concludes that innovative procurement and supply chain integration have contributed towards agility of the involved participants within the construction industry in the detailed mentioned case study. The study can be beneficial to all the stakeholders especially the client in managing supply chain.

The extraordinary success of many insect is due in large part to the evolution of powerful asynchronous flight muscles. Unlike twitch muscles, which contract one-for-one with motor spikes, these specialized muscles exhibit an accentuated form of stretch-dependent activation. The use of stretch as the primary means of activation and deactivation enables muscles to contract cyclically at high frequency without the requirement of large internal membrane compartments for calcium release and uptake. Although important both for the evolutionary radiation of insects and as a model system for muscle physiology, the physiology of asynchronous muscles is still poorly understood in many regards. Research reported here relates to two critical issues: (1) the means by which the power output of these muscles is regulated by the nervous system, and (2) the molecular basis of stretch activation. We studied the neural control of power output by recording muscle spikes in tethered fruit flies, Drosophila, subjected to visual stimuli that elicited changes in lift. We then constructed transgenic flies expressing the calcium reporter, cameleon, in the asynchronous muscles to measure the steady-state [Ca.sup.2+] levels produced by different frequencies of neural activation. The results suggest that flies may regulate power in asynchronous muscles by recruiting crossbridges via changes in sacroplasmic [Ca.sup.2 +] We studied the structural basis of stretch activation by aiming a narrow high energy x-ray beam at the flight muscles of Drosophila flying within a visual closed-loop flight arena. This technique makes it possible to measure the motion of structural proteins within an active muscle as it cyclically shortens and lengthens in a living animal. The results are consistent with recent independent research on the molecular basis of stretch-activation.