Cold Acclimation in Plants: Relationship Between the Lipid Composition and the Cryostability of the Plasma Membrane

Received 23 March 1999/ Accepted in revised form 9 April 1999     

蚜科长管蚜亚科戏蚜属和蓼蚜属的分类地位订正（同翅目：蚜科， 长管蚜亚科）

从形态学角度研究了蚜科Aphididae长管蚜亚科Macrosiphidinae戏蚜Sportaphis sporta Zhang和扁蓄蓼蚜Polygonaphis aciculansucta Zhang的分类地位。结果表明：戏蚜为静细长蚜Tenuilongiaphis stata Zhang and Zhong的同物异名,扁蓄蓼蚜为扁蓄童盾蚜Aspidaphis adjuvas (Walker)的同物异名; 戏蚜属Sportaphis Zhang为细长蚜属Tenuilongiaphis Zhang的同物异名,蓼蚜属Polygonaphis Zhang为盾蚜属Aspidaphis Gillette的同物异名。研究标本保存在中国科学院动物研究所动物标本馆、美国伊利诺伊大学 Illinois Natural History Survey（INHS）和法国自然历史博物馆（NHMF）。     

Review of the stiletto fly genus Actenomeros Winterton & Irwin (Diptera, Therevidae, Agapophytinae)

The endemic Australian genus Actenomeros Winterton & Irwin, 1999b is reviewed. Three species are transferred from Nanexila Winterton & Irwin, 1999a: Actenomeros aureilineata (Winterton & Irwin, 1999a) comb. n., Actenomeros intermedia (Winterton & Irwin, 1999a) comb. n. and Actenomeros paradoxa (Winterton & Irwin, 1999a) comb. n. A new species (Actenomeros budawangsp. n.) is described and figured from New South Wales. A key to species is presented.     

Breeding success of the colonist species Bubulcus ibis (Linnaeus, 1758) and four native species

This work evaluated the breeding success of Bubulcus ibis (Ardeidae), Egretta thula, Nycticorax nycticorax, Phimosus infuscatus and Plegadis chihi in Rio Grande do Sul during two consecutive nesting seasons. Mean clutch size for B. ibis was 2.59 in 1998/1999 and 2.49 in 1999/2000. The species with both the smallest and largest clutch was P. infuscatus, with 2.04 in 1999/2000, and 3.16 in 1998/1999. The highest mean number of nestlings per nest was 2.86 for P. chihi in 1998/1999 and the lowest was 1.85 for B. ibis in 1998/1999 and P. infuscatus in 1999/2000. In both nesting seasons all the species had major success, laying three eggs and raising two nestlings, exept for B. ibis. The breeding success for P. chihi varied from 1.54 young/nest in 1998/1999 to 0.4 in 1999/2000, whereas B. ibis ranged from 1.16 in the first period to 0.99 in the second.     

Preliminary investigation: the impact of the NCAA Wrestling Weight Certification Program on weight cutting

Historically, wrestling is a sport dependent on weight. Three tragic deaths in late 1997 prompted the National Collegiate Athletic Association (NCAA) to make a Wrestling Weight Certification Program (WWCP) mandatory to foster a safe competitive environment. One institution examined the impact of this program on weight cutting. Thirty-two NCAA Division I wrestlers completed the WWCP in the 1998-1999 season and 29 in 1999-2000. Eighteen (56%) of 32 wrestlers in 1998-1999 weighed in 10 or more pounds above the previous year's competition weight. Whereas, 28% weighed in 20 or more pounds above the previous year's competition weight. Weekly weight loss for the wrestlers in 1998-1999 revealed a substantial loss during the first week, possibly demonstrating the use of time-tested techniques for weight loss. However, in 1999-2000, the first week weight loss was less pronounced, with 65.8% of the weight being lost during the second half of the WWCP. Therefore, these wrestlers may be breaking the sport historic cycle of weight fluctuations through the WWCP.     

Ways of Inhabiting the World: Landscape Archaeology

Landscape Transformation and the Archaeology of Impact: Social Disruption and State Formation in Southern Africa. Warren R. Perry. New York: Kluwer Academic/Plenum Publishers, 1999. 182 pp.
Archaeologies of Landscape: Contemporary Perspectives. Wendy Ashmore and A. Bernard Knapp, eds. Oxford: Blackwell, 1999, 303 pp.
The Archaeology and Anthropology of Landscape: Shaping Your Landscape. Peter J. Ucko and Robert Layton. eds. London: Routledge, 1999. 525 pp.     

Poverty and Downward Mobility in the Land of Opportunity

Falling from Grace: Downward Mobility in the Age of Affluence. Katherine S. Newman. Berkeley; University of California Press, 1999. 328 pp.
"So You Think. Drive. Cadillac?": Welfare Recipients' Perspectives on the System and Its Reform. Karen Seccombe. Boston: Allyn and Bacon, 1999. 246 PP.
Braving the Street: The Anthropology of Homelessness. Irene Glasser and Rae Bridgman. New York: Berghahn Books, 1999. 132 pp.     

ADP is the cognate ligand for the orphan G protein-coupled receptor SP1999

P2Y receptors are a class of G protein-coupled receptors activated primarily by ATP, UTP, and UDP. Five mammalian P2Y receptors have been cloned so far including P2Y1, P2Y2, P2Y4, P2Y6, and P2Y11. P2Y1, P2Y2, and P2Y6 couple to the activation of phospholipase C, whereas P2Y4 and P2Y11 couple to the activation of both phospholipase C and the adenylyl cyclase pathways. Additional ADP receptors linked to Galpha(i) have been described but have not yet been cloned. SP1999 is an orphan G protein-coupled receptor, which is highly expressed in brain, spinal cord, and blood platelets. In the present study, we demonstrate that SP1999 is a Galpha(i)-coupled receptor that is potently activated by ADP. In an effort to identify ligands for SP1999, fractionated rat spinal cord extracts were assayed for Ca(2+) mobilization activity against Chinese hamster ovary cells transiently transfected with SP1999 and chimeric Galpha subunits (Galpha(q/i)). A substance that selectively activated SP1999-transfected cells was identified and purified through a series of chromatographic steps. Mass spectral analysis of the purified material definitively identified it as ADP. ADP was subsequently shown to inhibit forskolin-stimulated adenylyl cyclase activity through selective activation of SP1999 with an EC(50) of 60 nM. Other nucleotides were able to activate SP1999 with a rank order of potency 2-MeS-ATP = 2-MeS-ADP > ADP = adenosine 5'-O-2-(thio)diphosphate > 2-Cl-ATP > adenosine 5'-O-(thiotriphosphate). Thus, SP1999 is a novel, Galpha(i)-linked receptor for ADP.     

Effects of Low pH on the Induction of Root Hair Formation in Young Lettuce (Lactuca sativa L. cv. Grand Rapids) Seedlings

Received 13 August 1999/ Accepted in revised form 22 December 1999     

IS1999 increases expression of the extended-spectrum beta-lactamase VEB-1 in Pseudomonas aeruginosa

The integron-borne bla(VEB-1) gene encodes an extended-spectrum beta-lactamase. This gene was associated mostly with IS1999 and rarely with an additional IS2000 element in Pseudomonas aeruginosa isolates from Thailand, whereas IS1999 was only very rarely associated with bla(VEB-1) in Enterobacteriaceae. Expression experiments and promoter study identified promoter sequences in IS1999 that increased the expression of VEB-1 in P. aeruginosa.     

Dynamics of the factors of 137Cs transfer to natural and sown grasses in the long term after the accident at the Chernobyl power plant

The regularities of changes in factors of 137Cs transfer to natural and sown grasses in the longterm period after the Chernobyl accident are described. The dynamics of changes in factors of 137Cs transfer to sown grasses over the period of 1993 to 1999 was of a non-uniform character. On average, these transfer factors (TF) tended to decrease in that period. A significant tendency for an increase in TF to sown grasses was noted for 1997-1999. The half-life periods of decrease in TF to natural grasses in the period 1993-1999 were shown to be ranged from 4.6 to 24.6 years. It was demonstrated that the differences in the TF dynamics between sown and natural grasses were related to the peculiarities of their development and application of countermeasures.     

Ecological characteristics of aSuaeda japonica population and the effects of early-season air temperatures on population formation

A natural, tidal-flat population ofSuaeda japonica was studied to determine how air temperatures early in the growing season affected population formation. Changes in germination rates, density, standing crop (amount of biomass aboveground), and plant heights and weights were monitored from February 1999 to September 2000. Seed germination occurred between mid-February and early May in 1999, and from mid-February to mid-April in 2000. The daily mean air temperature fluctuated below and over 0°C through the end of March in 1999 and until mid-March in 2000. Seedling losses due to freezing were greater in 1999 than in 2000. Densities in 1999 and 2000 were 790 and 2201 plants/m² in the early growing season, and 578 and 803 plants/m² later on, respectively. Therefore, the density and mortality ofS. japonica was higher in 2000 than in 1999. Values of correlation were low between density and standing crop, but diverse between density and height. The variation in standing crops was remarkable but that of height was small among sites. Frequencies of size classes, based on height, followed normal distribution curves over time, but those based on weight were very great in the lower classes over the entire growing season.     

2种不同采样方法对麦田蜘蛛群落结构的比较研究

分别于1998年11月到1999年5月和1999年11月到2000年5月间,在位于武汉市武昌区的沙湖边,使用样方和陷阱法系统采样,研究了裸粒大麦田的蜘蛛群落结构。研究结果显示,1998-1999年麦田蜘蛛群落由11科44种蜘蛛组成,1999-2000年麦田蜘蛛群落由14科59种蜘蛛组成;相同年份不同采样方法获得的蜘蛛群落优势种组成不同,陷阱法采样获得的优势种集中在皿蛛科、狼蛛科和平腹蛛科,而样方采样虽然也以皿蛛科和狼蛛科蜘蛛为主,但球蛛科、肖蛸科和园蛛科蜘蛛的比例明显上升;不同的年份使用相同的采样方法获得的蜘蛛优势种组成不同,显示了群落结构的年际变动。对2种采样方法获得的群落相似性分析显示,不同采样方法获得的群落结构相似性较小。     

Inhibitory Effect of Sucrose on the Plasma Membrane H+ Pump Activity and Possible Involvement of the C-terminal Region in the Sucrose Effect

+ pump activity is unclear. In the plasma membrane vesicles from rye leaves high concentrations of sucrose had significant inhibitory effects on the plasma membrane H⁺ pump activity. Fusicoccin and trypsin treatment experiments suggest that the C-terminal region of the H⁺ pump may partially but significantly be involved in the sucrose effect. Received 20 August 1999/ Accepted in revised form 27 December 1999     

Across the Boundaries of Belief: Contemporary Issues in the Anthropology of Religion; Religion and Magic: Approaches and Theories

Across the Boundaries of Belief: Contemporary Issues in the Anthropology of Religion. Morton Klass and Maxine K. Weisgrau. eds. Boulder, CO: Westview Press, 1999. 416 pp.
Religion and Magic: Approaches and Theories. Graham Cunningham. New York: New York University Press, 1999. 126 pp.     

Effective cancer therapy with a single injection of interleukin-2 at the site of the tumour

Mice with a severe metastasized tumour burden can be cured with a single local injection of interleukin-2. Such a treatment can also be effective against ocular squamous cell carcinoma in cows and transmissible venereal tumours in dogs. We did not notice any toxic effects of this treatment. Received: 9 April 1999 / Accepted: 21 June 1999     

Structural changes in the neck linker of kinesin explain the load dependence of the motor's mechanical cycle.

The two-headed motor protein kinesin hydrolyzes ATP and moves on microtubule tracks towards the plus end. The motor develops speeds and forces of the order of hundreds of nanometers per second and piconewtons, respectively. Recently, the dependence of the velocity, the dissociation rate and the displacement variance on the load and the ATP concentration were measured in vitro for individual kinesin molecules (Coppin et al., 1997; Visscher et al., 1999) over a wide range of forces. The structural changes in the kinesin motor that drive motility were discovered by Rice et al. (1999). Here we present a phenomenological model for force generation in kinesin based on the bi-stable, nucleotide-dependent behavior of the neck linker. We demonstrate that the model explains the mechanical, kinetic and statistical (experimental) data of Coppin et al. (1997). We also discuss the relationship between the model results and experimental data of Visscher et al. (1999).     

Functional dissection of lipid and protein kinase signals of PIKfyve reveals the role of PtdIns 3,5-P2 production for endomembrane integrity.

PIKfyve enzymatic activity is required in maintaining late endocytic membrane integrity. PIKfyve is a dual specificity enzyme that phosphorylates phosphatidylinositol (PtdIns) and PtdIns 3-P at the 5-hydroxyl and unidentified endogenous protein substrate(s). To determine which of these activities (lipid versus protein kinase activity) is responsible for endomembrane homeostasis we analyzed a double mutant PIKfyve(K1999E/K2000E). These substitutions in the putative lipid-substrate activation loop nearly completely abrogated the lipid kinase activity without any significant effect on the protein kinase activity of PIKfyve(K1999E/K2000E). Expression of PIKfyve(K1999E/K2000E) in COS cells induced a dramatic dominant-negative effect in the form of endomembrane swelling and vacuolation. In addition, the lipid-substrate specificity of PIKfyve was modified by introducing single mutations in Lys-1999 or Lys-2000. This yielded proteins with preferentially abrogated synthesis of PtdIns 5-P (PIKfyve(K2000E)) or PtdIns 3,5-P(2) (PIKfyve(K1999E)), of which only the PIKfyve(K1999E) mutant induced the characteristic endomembrane defects upon cell transfection. Furthermore, phosphoinositide microinjection into cells demonstrated a selective ability of PtdIns 3,5-P(2) to correct the endomembrane defects induced by the dominant-negative PIKfyve lipid kinase-deficient mutants. Thus, PtdIns 3,5-P(2) production by PIKfyve is crucial for endomembrane integrity, and Lys-1999 most likely directs the PIKfyve interactions with the 3-phosphate group in PtdIns 3-P.     

Probability models and the applicability of statistical procedures in the identification of chromosomal fragile sites

Summary. Böhm et al. (1995, Human Genetics 95 , 249–256) introduced a statistical model (named FSM–fragile site model) specifically designed for the identification of fragile sites from chromosomal breakage data. In response to claims to the contrary (Hou et al., 1999, Human Genetics 104 , 350–355; Hou et al., 2001, Biometrics 57 , 435–440), we show how the FSM model is correctly modified for application under the assumption that the probability of random breakage is proportional to chromosomal band length and how the purportedly alternative procedures proposed by Hou, Chang, and Tai (1999, 2001) are variations of the correctly modified FSM algorithm. With the exception of the test statistic employed, the procedure described by Hou et al. (1999) is shown to be functionally identical to the correctly modified FSM and the application of an incorrectly modified FSM is shown to invalidate all of the comparisons of FSM to the alternatives proposed by Hou et al. (1999, 2001). Last, we discuss the statistical implications of the methodological variations proposed by Hou et al. (2001) and emphasize the logical and statistical necessity for fragile site identifications to be based on data from single individuals.     

Denitrification and bacterial community structure in the cascade of six reservoirs on a tropical river in Brazil

Hydrobiologia - Denitrification activity was measured by the acetylene blockage technique in six reservoirs of the Tietê River, southeastern Brazil, in March 1999 and July 1999. The total...