THE EXPANSION HISTORY OF ALUMINUM TARGETS RELEVANT TO X-RAY LASER SCHEMES

For the first time, the technique of point projection absorption spectroscopy - which uses an intense, point source of X-rays to project and spectrally disperse an image of a plasma onto a detector- has been shown to be applicable to the study of expanding aluminium plasmas generated by approximately 80ps (2-omega) laser pulses. Massive, stripe targets of approximately 125-mu-m width and wire targets of 25-mu-m diameter have been studied. Using a PET Bragg crystal as the dispersive element, a resolving power of approximately 3500 was achieved with spatial resolution at the 5-mu-m level in frame times of the order of 80ps. Reduction of the data for times up to 150ps after the peak of the incident laser pulse produced estimates of the temperature and densities present, as a function of space and time.

Life history of the rare red alga Tsengia bairdii (=Platoma bairdii) (Nemastomataceae, Rhodophyta) from Scotland

A single thallus of the rare red seaweed Tsengia bairdii (Farlow) K. Fan et Y.Fan( Platoma bairdii (Farlow) Kuckuck) (Nemastomataceae) was collected on a subtidal pebble on the west coast of Scotland. The terete gelatinous axes, which were only 7 mm high, were monoecious. They bore numerous cystocarps and a few spermatangia, which represent the first observation of male structures in this genus. Released carpospores grew into expanded basal discs that gave rise to erect axes bearing irregularly cruciate tetrasporangia. irregularly cruciate to zonate tetrasporangia were also formed on these basal discs. Karyological studies on dividing tetrasporocytes showed about 25 bodies, identified as paired meiotic chromosomes on the basis of their size in comparison to mitotic and meiotic chromosomes in other red algal species. These observations confirm the isomorphic life history inferred from early field collections and show that this species is monoecious. Tsengia bairdii is an extremely rare seaweed in Europe - it seems to be confined to sublittoral cobbles and has a temporally patchy distribution.

Natural history of idiopathic erythrocytosis - A retrospective case series review

Idiopathic Erythrocytosis (IE) is a diagnosis given to patients who have an absolute erythrocytosis (red cell mass more than 25% above their mean normal predicted value) but who do not have a known form of primary or secondary erythrocytosis (BCSH guideline, 2005). We report here the results of a follow-up study of 80 patients (44 male and 36 female) diagnosed with IE from the United Kingdom and the Republic of Ireland over a 10 year period. Baseline information was initially collected when investigating for molecular causes of erythrocytosis in this group. The diagnosis of IE was made on the basis of a raised red cell mass >25% above mean normal predicted value, absence of Polycythaemia Vera (PV) based on the criteria of Pearson and Messinezy (1996), and the exclusion of secondary erythrocytosis (oxygen saturation >92% on pulse oximetry, no history of sleep apnoea, no renal or hepatic pathology, and a normal oxygen dissociation curve (if indicated). The average age at diagnosis of erythrocytosis was 34.5 (2–74 years). Erythropoietin levels were available for 77/80 of the patients and were low in 18 (23%) and normal or high in 59 (74%). Ultrasound imaging was carried out in 67 patients (84%) at time of diagnosis and no significant abnormalities found. Fourteen patients had a family history of erythrocytosis. These patients have now been followed up for an average of 9.4 years (range 1–39). Out of 80 patients 56 patients can still be classified as having IE, of whom 52 are living (cause of death in the other 4 - lung cancer, RTA, sepsis, unknown). Thirty-five of these patients are regularly venesected, 3 take hydroxyurea (one also venesected), 11 receive no treatment while treatment is unknown in 2. Twenty take aspirin, 1 warfarin and 31 no thromboprophylaxis. Four of these patients had suffered thromboembolic complications (3 with CVA/TIAs and 1 with recurrent DVT) at or before their original diagnosis. Since diagnosis 8 patients have had 9 thrombotic events of which 7 were arterial (1 CVA, 3 TIAs, 1 MI, 2 PVD) and 2 venous (DVT/PE). Twenty take aspirin, 1 dipyridamole, 1 warfarin and 30 take no thromboprophylaxis. Out of the 24 patients who now have a diagnosis other than IE, 8 have been diagnosed with myelo-proliferative disease. Thirteen patients have a molecular abnormality which is likely to account for their erythrocytosis (11 VHL, 1 PHD-2, 1 EPO-receptor mutations). Three patients have secondary erythrocytosis. Older case studies identified a heterogenous group of patients, some of whom probably had apparent erythrocytosis and some who had either primary polycythaemia or secondary causes later identified (Modan and Modan, Najean et al). More recent reviews have identified a more homogenous group with low rates of transformation to myelofibrosis/acute leukaemia and low rates of thrombosis of around 1% patient-year. Follow up of our initial patient group does indeed reveal a heterogeneous group of patients with 10% now diagnosed with an MPD, although when analysis is confined to those patients who continue to fulfil the criteria for IE, the clinical course has been more stable. There has been no progression to MDS or leukaemia in this group (one patient with PV progressed to AML). The rate of thrombosis is 1.6% patient-years which is lower than the rate seen in PV and is consistent with the rate identified in other series. Molecular defects continue to be identified in this group and future investigation is likely to reveal further abnormalities.

Discovery and evolving history of two genetically related but phenotypically different viruses, porcine circoviruses 1 and 2

Porcine circoviruses (PCVs) belong to the genus Circovirus, family Circoviridae. and are the smallest non-enveloped, single stranded, negative sense, circular DNA viruses that replicate autonomously in mammalian cells. Two types of PCV have been characterised, PCV1 and PCV2 and these two viruses show 83% sequence identity at open reading frame (ORF) 1 and 67% identity at ORF2. PCV1 is a nonpathogenic virus of pigs. In contrast, PCV2 has emerged as a major pathogen of swine around the world. The discovery of PCV1 and how the subsequent studies on this virus eventually led to the recognition and characterisation of PCV2, and the disease scenarios associated with PCV2, serve as a model of how multidisciplinary collaboration among field veterinarians, diagnosticians and researchers can lead to the rapid characterisation and control of a globally important emerging disease. (C) 2011 Elsevier B.V. All rights reserved.

An ecotoxicological approach to assessing the impact of tanning industry effluent on river health

A study was conducted to investigate the sediment health and water quality of the River Sagana, Kenya, as impacted by the local tanning industry. Chemical analysis identified the main chemical pollutants (pentachlorophenols and chromium) while a bioassay addressed pollutant bioavailability. The bioassay, exploiting the luminescence response of a lux marked bacterial biosensor, was coupled to a dehydrogenase and Dapnia magna test to determine toxicity effects on sediments. Results highlighted the toxicity of the tannery effluent to the sediments at the point of discharge (64% of control bioluminescence) with gradual improvement downstream. There was a significant increase in dehydrogenase downstream, with the enzyme activity attaining a peak at 600 m, also indicating a gradual reduction of toxicity. Biological oxygen demand (19.56 mg L(-1)) dissolved oxygen (3.97 mg L(-1)) and high lethal dose value (85%) of D. magna also confirmed an initial stress at the point of discharge and recovery downstream. Optical density of surface water demonstrated an increase in suspended particulates and colour after the discharge point, eventually decreasing beyond 400 m. In conclusion, the study highlighted the importance of understanding the biogeochemistry of river systems impacted by industries discharging effluent into them and the invaluable role of a biosensor-based ecotoxicological approach to address effluent hazards, particularly in relation to river sediments.