Recreational fishing impacts on threatened river sharks: A potential conservation issue

The Adelaide River in Australia's Northern Territory is a popular recreational fishing area, as well as habitat for threatened and protected river sharks (Glyphis species). Both the Critically Endangered Speartooth Shark (Glyphis glyphis) and Endangered Northern River Shark (Glyphis garricki) are identified here in illegal catches from recreational angling. The identification of a decayed shark specimen using a DNA barcoding‐like approach is the first such application to the identification of protected sharks in a recreational fishery. While the extent of catches by recreational anglers is unknown, the threatened status of these sharks, their suspected low population sizes, restricted distributions and importance of the Adelaide River as a nursery area call for the consideration of this as a potential conservation issue. As such, appropriate measures should be taken to reduce interactions with recreational anglers. The primary target species in the river is the iconic sportfish, Barramundi, which is predominantly caught by unbaited lure. Sharks are rarely caught on lure, allowing an opportunity for mitigation to focus on a fishing activity (baited hooks) which would limit any regulatory impact on popular lure fishing. Potential mitigation measures range from increased angler education and compliance checks, to the implementation of a spatial closure to baited hook fishing (a lure‐only zone). Such measures may assist in meeting a stated objective of the Australian Government's river shark Recovery Plan to ‘reduce and, where possible, eliminate adverse impacts of recreational fishing'.     

Uptake and resource allocation of inorganic carbon by the temperate seagrasses Posidonia and Amphibolis

Productivity measurements from carbon uptake have been suggested as good indicators of the physiological health of seagrasses. As seagrasses acquire carbon from the surrounding water, the rate of uptake often provide a good measure of the efficiency at which seagrasses meet their resource demands for growth. This rate is often used to assess the photosynthetic efficiency of the plants, a proxy for the physiological status of seagrass. This has special relevance to the Adelaide region as over 5000 ha of seagrasses have been lost from Adelaide coastal waters over the last 70 years, with much of this loss attributed to nutrient inputs from wastewater, industrial and stormwater discharges. This study used an in-situ inorganic carbon isotope-labelling and spike approach to obtain ecologically relevant estimates of seasonal variability in carbon uptake and its allocation in two species of temperate seagrass common to this coast (Amphibolis antarctica and Posidonia angustifolia). Uptake of carbon by the seagrass complex (leaves, roots, phytoplankton and epiphytes) was affected by both season and species. Carbon uptake rates of phytoplankton were generally higher than other components of the system. Uptake rates ranged from 0.01 mg C g^− 1 DW h^− 1 (summer) to 0.61 mg C g^− 1 DW h^− 1 (spring) in Posidonia and 0.02 mg C g^− 1 DW h^− 1 (summer) to 0.93 mg C g^− 1 DW h^− 1 (winter) in Amphibolis. Carbon uptake by the Amphibolis complex was higher than in the Posidonia complex. The Amphibolis complex had higher uptake rates in summer whereas the Posidonia complex was higher in spring. Fine sediments probably from a nearby dredging operation, are likely to have resulted in lower carbon uptake and a reduction in the above-ground and below-ground biomass in summer.     

Chlorophyll isolation,structure and function: major landmarks of the early history of research in the Russian Empire and the Soviet Union

This paper covers major events of the early history of chlorophyll research in the Russian Empire and the Soviet Union from 1771 until 1952, when the modern period of studies on photosynthesis began in full swing. Short biographical sketches of key scientists, reviews of their major research contributions and some selected photographs are included. This revised version was published online in August 2006 with corrections to the Cover Date.     

巴戟天根的结构及其与蒽醌类化合物积累的关系

应用石蜡切片法、荧光显微镜和紫外分光光度法,对不同年生巴戟天根组织结构的变化进行了观察、对蒽醌类化合物在根中的分布场所及其积累动态进行了研究。结果表明:巴戟天根的结构类似一般多年生草本植物,薄壁细胞是巴戟天根中蒽醌类化合物的分布储存场所,蒽醌类化合物含量随着根生长年限的增加而增加。由以上研究总结出巴戟天以四年或四年以上采收为好,并以根皮厚、木心细者为上品。     

Protein intake regulation in the weanling rat: Effects of additions of lysine,arginine and ammonia on the selection of gluten and energy

The effects of adding lysine, arginine and ammonia to gluten on the self-selection of protein and energy by the weanling rat simultaneously offered a choice of two diets differing only in gluten concentration (15 and 55%) were tested. Previous studies have shown that while lysine (6 g/100 g) additions to gluten decreased the amount of gluten selected by the rat from 40 to 20 g per 100 g of food eaten, selection was not related to the nutritional quality of the gluten. When graded levels of arginine (1.8, 3.6 or 7.2 g/100 g) were added to the gluten with or without lysine (0 or 6 g/100 g) the dietary protein selection was unaffected. The addition of ammonia (1.4 g/100 g as NH₄Cl) to gluten had initially the same effect as lysine (6 g/100 g) but with time protein intake returned to control levels. This effect of ammonia was unaltered by arginine additions. It is concluded that the mechanisms which lead to decreases in gluten selection caused by lysine or ammonia are not similar, and that the effects of lysine on gluten selection are not caused by an increased arginine requirement for urea cycle activity.     

自分泌生长因子对早期胚胎体外发育的影响(简报)

生长因子(Growth Factors,GFs)对于调节哺乳动物胚胎的早期发育和分化起着重要作用,这些GFs存在于雌性生殖道,也可由胚胎自身合成。正是由于这种自分泌GFs的存在,使我们可以通过改变胚胎培养密度或添加外源性GFs来定性或定量研究GFs对胚胎发育和分化的影响,对于了解GFs在分子水平上的作用途径和机制有着重要的意义。     

河南玉兰属两新变种

发表河南玉兰属两新变种,即：①狭被望春玉兰(Yulania biondii (Pamp.) D. L. Fu var. angustitepala D. L. Fu, T. B. Zhao et D. W. Zhao,var. nov.);②椭圆叶罗田玉兰(Y. pilocarpa (Z. Z. Zhao et Z. W. Xie) D. L. Fu var. ellipticifolia D. L. Fu, T. B. Zhao et J. Zhao,var. nov.)。     

刺叶柄棘豆的一个新变型--白花刺叶柄棘豆

描述了棘豆属(豆科)刺叶柄棘豆(Oxytropis acipblla Ledeb．)的一个新变型：白花刺叶柄棘豆O．aciphylla Ledeb．f．albiflora Z．Y．Chang,Z．H．Wu et L．R．Xu。原变型的花冠为红紫色或蓝紫色,而新变型的花冠为白色。     

The effect of intrauterine infusions of prostaglandin E2 on luteal function in nonpregnant gilts

Two trials were conducted to study the effects of intrauterine infusions of prostaglandin E(2) (PGE(2)) on luteal function in nonpregnant gilts. Cannulae were surgically implanted on day 9 postestrus into the lumen of each horn with a cephalic vein cannula inserted for collection of peripheral blood. Intrauterine infusions of 0, 25, 75 or 200 mug of PGE(2) were initiated at 0900 h on day 12 and administered thereafter every 12 hr until estrus or day 22 in the first trial. The second trial protocol included an increase in the dose of PGE(2) administered as well as the frequency of infusion. Infusion of 0, 200, 300 or 400 mug PGE(2) was begun at 0300 h on day 12 and continued every 6 hr until estrus or day 22. Cephalic plasma samples for progesterone analysis were collected every six hours from 0300 h on day 11 to 2100 h on day 26 in both trials. In Trial 1 mean plasma progesterone concentrations for all treatments were not different (P>0.05) from the controls on any given day of the estrous cycle. Interestrous interval was unaffected by intrauterine infusion of PGE(2). The mean plasma progesterone concentrations for all treatments were not different (P>0.05) from the controls on days 11-18 of the estrous cycle in Trial 2. However, plasma progesterone concentrations for the 200-mug and 300-mug PGE(2) groups appeared to be greater than the controls on days 14 and 15, indicating a possible delay in the decline of progesterone for these groups. The mean plasma progesterone concentrations for the treatment groups were lower (P<0.05) than the controls on days 20-26 of the cycle. treatment cycle length did not differ (P>0.05) from previous cycle length; thus treatment with PGE(2) had no effect on interestrous interval. PGE(2) may have retarded the decline of progesterone secretion by the corpus luteum in some cases, but at these dosages and frequencies of administration PGE(2) was ineffective in prolonging luteal maintenance.     

Molecular structure for microbial polysaccharides: conformation of the Klebsiella serotype K9 capsular polysaccharide

Fibre type X-ray diffraction patterns have been obtained from oriented, semicrystalline films prepared from the sodium salt form of the bacterial capsular polysaccharide of Klebsiella serotype K9. The molecule has a pentasaccharide repeating sequence, with four neutral residues in the backbone and a glucoronic acid side chain. A novel feature of the molecule is the incorporation of α-l-rhamnose residues, one 1,2 linked and two 1,3 linked in the backbone. Analysis of the X-ray diffraction results indicate an extended three-fold helical conformation with an axially projected chemical repeat of 1.377 nm. Both left and right handed helices have been examined using linked atom least squares techniques to optimize the stereochemistry while simultaneously meeting the observed helical parameters.     

A New Family of Entodiniomorph Protozoa from the Marsupial Forestomach, with Descriptions of a New Genus and Five New Species

ABSTRACT. A unique group of entodiniomorph protozoa was found in forestomach contents from quokka ( Setonix brachyurus ), western grey kangaroo ( Macropus fuliginosus ), red kangaroo ( Macropus rufus ) and euro ( Macropus robustus erubescens ). A new genus, Macropodinium n.g., containing five new species, is described. Three species are described from forestomach contents of the quokka: Macropodinium baldense n. sp., Macropodinium moiri n. sp. and Macropodinium setonixum n. sp. A single species, Macropodinium ennuensis n. sp., is described from the red kangaroo and euro. The last species, Macropodinium yalanbense n. sp., is described in forestomach contents from the western grey kangaroo. At least three distinct features in the new genus are incompatible with any of the described families in the order Entodiniomorphida. On this basis, the new family Macropodiniidae has been created.     

内蒙古大兴安岭白头翁属一新变种

描述了毛茛科白头翁属一新变种——裂萼细叶白头翁(Pulsatilla turczaninovii Kryl.et Serg.var.fissasepalum)。本变种与原变种细叶白头翁的主要区别为,外轮萼片有不等深度、不等大小的二深裂,中裂片最大,两侧裂片大小不等。     

Comparative induction of unscheduled DNA synthesis by physical and chemical agents in non-proliferating primary cultures of rat hepatocytes

The incorporation of [³H]thymidine into DNA due to unscheduled DNA synthesis (UDS) induced by N-OH-2-acetylaminofluorene (N-OH-AAF), aflatoxin B₁ (AFB₁), ethyl methanesulfonate (EMS) and ultra-violet light was quantitated by autoradiography and by scintillation spectrometry on acid precipitable macromolecules or DNA insolated by isopycnic banding in cesium chloride (CsCl). Dose-dependent increases in UDS due to N-OH-AAF and AFB₁ treatment were found. Only 2-fold increases at the highest dose levels were found, however, when incorporated [³H]thymidine was quantitated by scintillation spectrometry. Seven, 11, and 25-fold increases in UDS induced by AFB₁, N-OH-AAF and ultra-violet light, respectively, were found when incorporated [³H]thymidine was quantitated by autoradiography, indicating a high sensitivity for detecting ‘long patch’ repair by this technique. Scintillation spectrometry was completely ineffective in detecting EMS-induced UDS, whereas autoradiography demonstrated a small, but significant induction in [³H]thymidine incorporation at high dose levels. The non-proliferative nature of the primary hepatocyte prohibits the uniform radioactive prelabeling of DNA, necessary in other techniques, for the detection of ‘short patch’ repair induced by compounds such as EMS. Therefore, the sensitivity of the primary cultured rat hepatocyte in conjunction with UDS for detecting DNA damage caused by mutagens and carcinogens which induce ‘short patch’ repair may be limited to the autoradiographic analysis of the unscheduled incorporation of [³H]thymidine.