bluuebunny/crossref_metadata_2025 huggingface dataset:
The carotenoids of the marigold, Tagetes erecta
Authors: Alam A. U. , Couch J. R. , Creger C. R.
Published: August 2008

Pigments of Tagetes erecta petals have been separated by the use of multiple fractional extractions and thin-layer chromatography and analyzed by spectral methods. The petals showed a predominance of xanthophylls (98.7%) and only a small amount of carotenes. On the basis of absorption studies, lutein (64.1%), antheraxanthin (31.1 %), α-cryptoxanthin (3.1%), (β-carotene (0.6%), phytofluene (0.4%), and α-carotene (0.15%) have been characterized.
Electron microscopy of the conidial protoplasts of Neurospova crassa
Authors: Manocha M. S.
Published: August 2008

Micromorphology of conidia resembles that of young hyphae except for the details of the cell wall structure, which is thicker and prominently developed in unhydrated conidia. Although mitochondria and endoplasmic reticulum are present in ungerminated conidia, these organelles increase greatly during germination, and vacuoles increase in size and number. Naked protoplasts protrude through a small pore in the partially digested wall of the conidium. Free protoplasts synthesize new wall material when incubated in a regenerative mixture. Similarities and differences between conidial germination and protoplast formation and regeneration are noted.
Plasmodesmata between guard cells and accessory cells
Authors: Litz R. E. , Kimmins W. C.
Published: August 2008

Plasmodesmata have been demonstrated in three dicotyledon species between the stomatal guard cells and the accessory cells.
A paleomagnetic test for northward tectonic transport of the eastern Selwyn Basin, northern Canadian Cordillera: data from the mid-Cretaceous Ragged Pluton
Authors: Symons D. T.A. , Kawasaki K. , Hart C. J.R. , Harris M. J.
Published: August 2008

Ragged Pluton is a member of the Tungsten Plutonic Suite in the eastern Selwyn Basin. This circular massive 97 Ma granitic pluton is ∼5 km in diameter. It intrudes deformed and metamorphosed clastic strata of the Neoproterozoic to Lower Cambrian Vampire Formation. Thermal and alternating field step demagnetization data for 216 specimens from 21 plutonic sites isolated a stable characteristic remanent magnetization (ChRM) direction at 20 sites of declination D = 325.9°, inclination I = 80.4° (α95 = 2.7°, k = 142). Thermal demagnetization and saturation remanence analysis show that the ChRM is carried by both single-domain pyrrhotite and magnetite. Ragged Pluton’s paleopole at 73.9°N latitude, 191.4°E longitude (dp = 5.0°, dm = 5.2°) is concordant with its co-eval 97 Ma North American reference paleopole, showing at 95% confidence that the pluton has not been significantly rotated or translated relative to North America. This paleomagnetic result favours tectonic models in which the eastern Selwyn Basin is autochthonous, or nearly so, since the mid Cretaceous.
Effect of Fish Size on the Reactive Distance of Bluegill (Lepomis macrochirus) Sunfish
Authors: Breck James E. , Gitter Michael J.
Published: August 2008

We hypothesized that visual acuity in fishes and thus reactive distance should increase with fish size; visual acuity depends on eye lens diameter and cone density in the retina, and eye lens diameter increases with fish size. Though cone density declines in larger fish, we expected this effect to be relatively small. We tested this hypothesis for a behavioral measure of visual acuity, the reactive distance of bluegill (Lepomis macrochirus) sunfish to zooplankton prey, in aquaria (375 L) for fish from 27 to 162 mm standard length. Reactive distance increased nonlinearly with fish size; the rate of increase in reactive distance slows in larger fish. For fish of a given size, reactive distance was dependent on prey size, but visual angle measured from the fish eye was nearly constant. Whereas lens diameter and visual acuity increase with fish size in bluegills, the acuity of larger fish is less than expected from eye lens diameter alone. This is probably a result of cone density decreasing with fish size, as has been found for other fishes. The observed fish-size-dependent differences in reactive distance imply very large differences in visual volumes and encounter rates with prey among size-classes of bluegills. Habitat segregation among bluegill size-classes may prevent the intense intraspecific competition for prey that would be expected, in part, from the superior visual acuity of larger fish.Key words: foraging, reactive distance, size-class interactions, bluegill, Lepomis macrochirus; predation, visual acuity, zooplankton
Factors Influencing the Size of American Lobster (Homarus americanus) Stocks Along the Atlantic Coast of Nova Scotia, Gulf of St. Lawrence, and Gulf of Maine: A New Synthesis
Authors: Harding Gareth C. , Drinkwater Ken F. , Vass W. Peter
Published: August 2008

The general aspects of fluctuating American lobster (Homarus americanus) stocks are considered in an attempt to identify common principles controlling lobster populations in the Gulf of Maine, Gulf of St. Lawrence, and the Atlantic coast of Nova Scotia. Inshore fishing mortality is known to be precariously high in both Canadian and American waters yet only in the central Northumberland Strait region and along the Atlantic coast of Nova Scotia are stocks experiencing steep declines. Existing regulations allow fishing of lobsters well below the size at which maturity can be expressed. In western and central Northumberland Strait female lobsters are not protected by the 'berried' law because of the timing of the fishing season. Climatic change, expressed as sea-surface temperature, is closely associated with the success of lobster recruitment in the Gulf of Maine, but nowhere else. Huntsman's hypothesis that warm surface water of sufficient duration is essential for the successful completion of the larval stages of the lobster is found to have wide application. Warmer waters are also found to have a preponderance of plankton in the size categories required for feeding by the first two larval stages. Both the southern Gulf of St. Lawrence and the southwestern Gulf of Maine, including Georges Bank, are believed to be prolific nursery grounds for the early larval lobsters because warm water with plenty of food stimulates rapid development and settling. We calculated that larvae released on Georges Bank supply recruits to southern Nova Scotia, Bay of Fundy, and Maine, whereas some larvae from the southern Gulf of St. Lawrence are thought to settle as far as Cape Breton Co., N.S., and before the closure of the Strait of Canso, Guysborough Co., N.S. The past importance of lobster recruitment to the Atlantic coast of Nova Scotia through the Strait of Canso is estimated to have been as high as 60% of the average landings in Chedabucto Bay during the 11 best years of this fishery. The failure of the Atlantic coast lobster fishery off Nova Scotia is believed to have been initiated by a larval recruitment failure caused by the synchronous closure of the Strait of Canso and the start of a general climatic cooling. Possibly a critical temperature was reached along the Atlantic coast of Nova Scotia in the 1950s below which larval survival is much reduced by the shortened season. Reduced lobster abundance along the Atlantic coast of Nova Scotia may have contributed to the imbalance in the benthic ecosystem in which an uncontrolled urchin population consumed the kelp beds and until recently greatly reduced the primary production input to the system.Key words: American lobster, Homarus americanus; stocks, recruitment, ecology, larval transport
Seasonal Dynamics of the Deep-Chlorophyll Maximum in Castle Lake, California
Authors: Priscu John C. , Goldman Charles R.
Published: August 2008

Vertical profiles of chlorophyll concentration measured during 1980 in Castle Lake showed that a deep maximum developed immediately after ice thaw and persisted in the deep basin of the lake until autumn overturn. In the early portion of the ice-free season, low epilimnetic turbidity allows enough light to reach this deep-chlorophyll layer to produce a deep-primary productivity maximum. Photoautotrophic growth appears to maintain the deep-chlorophyll maximum early in the season whereas the accumulation of sinking organisms appears to do so later in the season. Although the deep-water phytoplankton have reduced rates of photosynthesis late in the season, they maintain their ability to photosynthesize immediately upon exposure to light. Consequently, the redistribution of deepwater chlorophyll at fall overturn can increase the chlorophyll concentration of the euphotic zone (0–15 m) by 58% which can potentially increase primary productivity in this zone by 81%.Key words: deep-chlorophyll maximum, primary productivity, aphotic viability
Salmon Stock Identification Based on Elemental Composition of Vertebrae
Authors: Mulligan T. J. , Lapi L. , Kieser R. , Yamada S. B. , Duewer D. L.
Published: August 2008

The elemental chemical composition of salmon vertebrae has been measured by X-ray spectroscopy for two mixtures of stocks. Classification of fish to stock based on this composition has an accuracy in the range of 80–95%. Information on the techniques used, X-ray fluorescence spectroscopy and pattern recognition analysis, is presented for a reader with no background in these areas. The advantages and limitations of this method of stock identification are discussed.Key words: X-ray spectroscopy, pattern recognition analysis, stocks, salmon, management
Bacteria Decomposing Amino Acids in Bulk-Stored Capelin (Mallotus villosus)
Authors: Kjosbakken J. , Storrø I. , Larsen H.
Published: August 2008

Bacteria that decompose amino acids were isolated from anaerobically stored capelin (Mallotus villosus) depleted of trimethylamine oxide (TMAO). Some of the 19 isolated strains could be assigned to Lactobacillus, or Bacteroidaceae, but others were not easily identified. Bacteria of the family Bacteroidaceae dominated the anaerobic viable count in the capelin mass in a period after the total reduction of TMAO. Most of the isolated strains differed from each other by decomposing different sets of the free amino acids, or decomposing amino acids at different rates during anaerobic growth in capelin extracts. Most strains isolated from the fish at the later stages of storage, and notably the Bacteroidaceae, produced copious amounts of NH3. Hydrophilic amino acids were the main source of the NH3 produced. Hydrophobic amino acids and other nonprotein nitrogenous components of the capelin extract were not decomposed by any of the 19 organisms, with the exception of the quantitatively less significant hypoxanthine, which was decomposed by three of the strains. Members of the family Bacteroidaceae may be prominent spoilage bacteria in fish, having until now escaped attention because of their obligate anaerobic and psychrotrophic nature.
A Recurrent Red Tide in a British Columbia Coastal Lagoon
Authors: Robinson M. G. , Brown L. N.
Published: August 2008

The development of a recurrent fall red tide in Esquimalt Lagoon, British Columbia, has been monitored over an 8-yr period, including an intensive 1-yr field study. We suggest that growth of the organism, Gymnodinium sanguineum Hirasaka, which causes the tides, is regulated by the availability of nitrate supplied in runoff. Its decline is attributed to the seasonal decrease in the availability of light. The source of the seed population for these recurring blooms is unclear, although we propose that transport from California by the California Undercurrent is involved.
The English–Wabigoon River System: I. A Synthesis of Recent Research with a View towards Mercury Amelioration
Authors: Rudd John W. M. , Turner Michael A. , Furutani Akira , Swick Alison L. , Townsend B. E.
Published: August 2008

Over a 3-yr period, teams from the federal Department of Fisheries and Oceans, the federal Department of the Environment, and the Ontario Ministry of the Environment researched the mercury pollution problem of the English–Wabigoon River system, north-western Ontario, Canada. Mercury methylation and bioaccumulation were occurring mainly in the water column and surface layers of the sediments. Most mercury in the system was buried below the surficial sediments and probably does not contribute substantially to present mercury bioaccumulation. Movement of mercury between geochemical and biological compartments was rapid within the water column and surface sediments. Also, substantial amounts of inorganic and methyl mercury were transported down the river–lake system, having been released from stretches of river upstream of Clay Lake and deposited onto the surfaces of downstream lake sediments. Because of the constant movement of mercury into the water and onto downstream surface sediments, mercury amelioration procedures should concentrate on reducing bioaccumulation rates from both the water column and surface sediments. Treatments such as a single addition of clean clay to the surface sediments of lakes would probably be unsuccessful as long as significant downstream movement of mercury continues. Semicontinuous resuspension of bottom sediments followed by downstream deposition and/or elevation of the selenium concentration in biota by low-level additions of selenite were found to be the two most promising amelioration strategies. Both of these approaches would treat the problem in the water column and surface sediments. We consider advantages and disadvantages of these ideas and some needs for further research.
Humpback Whales (Megaptera novaeangliae) Fatally Poisoned by Dinoflagellate Toxin
Authors: Geraci Joseph R. , Anderson Donald M. , Timperi Ralph J. , St. Aubin David J. , Early Gregory A. , Prescott John H. , Mayo Charles A.
Published: August 2008

During a 5–wk period beginning in late November, 1987, 14 humpback whales, Megaptera novaeangliae, died in Cape Cod Bay after eating Atlantic mackerel, Scomber scombrus, containing saxitoxin (STX), a dinoflagellate neurotoxin responsible for paralytic shellfish poisoning in humans. We propose a line of evidence to explain how whales, by virtue of their diving adaptations, may be particularly vulnerable to this systemic neurotoxin. Absence of STX in New England waters and shellfish during the episode suggests that the mackerel, representing the northern stock which spawns in the Gulf of St. Lawrence, accumulated the toxin there and delivered it to the Gulf of Maine and Cape Cod Bay in the fall of 1987. These findings challenge common perceptions of the manner in which planktonic toxins move through the food chain, and offer new insights into natural mortality and standings of marine mammals. It seems appropriate to search for STX and other phytotoxins when investigating marine mammal mortalities.
The ratio of ±KTS splice variants of the Wilms’ tumour suppressor protein WT1 mRNA is determined by an intronic enhancer
Authors: Yang Cheng , Romaniuk Paul J.
Published: August 2008

Alternative splicing of the primary transcript of the Wilms’ tumour suppressor gene WT1 involving 2 overlapping 5′ splice sites at the end of exon 9 results in the insertion of 2 amino acids (KTS) between zinc fingers 3 and 4 of the protein. The presence or absence of these 3 amino acids has consequences for DNA binding affinity, protein–protein interactions, and subnuclear localization. Disruption of the characteristic +KTS to –KTS ratio of mRNA isoforms as a result of mutations in the +KTS splice site results in Frasier syndrome. Mutational analysis of a WT1 minigene construct was carried out to search for sequences that regulate the ±KTS alternative splicing event. A strong pyrimidine-rich intronic enhancer that increases the use of the +KTS splice site was identified. Cross-linking experiments with nuclear extracts demonstrated that this enhancer specifically binds a protein with a molecular mass of 42 ± 2 kDa. One candidate for this trans-factor is the splicing regulator TIA-1, which binds to the pyrimidine-rich enhancer in the primary transcript from the minigene construct and increases the ±KTS splicing ratio. The observation that TIA-1 and WT1 are both involved in apoptosis supports our proposal for a functional link between these proteins.
Kinetics, substrate specificity, and stereospecificity of two new protein tyrosine phosphatase-like inositol polyphosphatases from Selenomonas lacticifex
Authors: Puhl Aaron A. , Greiner Ralf , Selinger L. Brent
Published: August 2008

Inositol polyphosphatases (IPPases) play an important role in the metabolism of inositol polyphosphates, a class of molecules involved in signal transduction. Here we characterize 2 new protein tyrosine phosphatase-like IPPases (PhyAsl and PhyBsl) cloned from Selenomonas lacticifex that can hydrolyze myo-inositol hexakisphosphate (InsP6) in vitro. To determine their preferred substrates and stereospecificity of InsP6 dephosphorylation, a combination of kinetic and high-performance ion pair chromatography studies were conducted. Despite only 33% amino acid sequence identity between them, both enzymes display strict specificity for IPP substrates and cleave InsP6 primarily at the d-3-phosphate position (>90%). Furthermore, both enzymes predominantly degrade InsP6 to Ins(2)P via identical and very specific routes of dephosphorylation (3,4,5,6,1). Despite these similarities, PhylAsl is shown to have a slight kinetic preference for the major inositol pentakisphosphate intermediate in its InsP6 hydrolysis pathway, whereas PhyBsl displays a unique and substantial preference for an inositol tetrakisphosphate intermediate.
Effect of a predator's visit on the spatial distribution of bank voles: experiments with weasels
Authors: Jędrzejewski Włodzimierz , Jędrzejewska Bogumiła
Published: August 2008

A series of experiments in seminatural conditions with bank voles Clethrionomys glareolus (Schreber, 1780) and weasels Mustela nivalis Linnaeus, 1766 was designed to show if (i) a short visit by a weasel into an area, and (ii) its scent alone left there, would influence the use of space by bank voles, and whether the age, sex, and reproductive activity of bank voles would differentiate their responses to the risk of predation. Forty-five bank voles were released into an outdoor enclosure (150 m2) divided into three pens of equal size. The risk of predation was manipulated by introducing a weasel into either one or two pens for 24 or 2 h. Changes in the use of space by voles were determined by livetrapping in pens for 11 days after each manipulation. The pens that had been penetrated by weasels were avoided by voles for several days following each introduction of a weasel. The pens where prey had contacted a predator, or where only the odour of a weasel remained, were equally avoided by voles. Sex- and age-related differences in response to risk were noted in bank voles: subadults and nonreproductive adults of both sexes, and reproductively active adult males, shifted their positions significantly after a weasel had penetrated their home pen. Juveniles of both sexes and reproducing females did not abandon their ranges.
Structure and functions of the digestive tract of Alvinella pompejana, a hydrothermal vent polychaete
Authors: Saulnier-Michel C. , Gaill F. , Hily A. , Alberic P. , Cosson-Mannevy M. A.
Published: August 2008

The different parts of the digestive tract of Alvinella pompejana are described. The buccal apparatus presents a ventral pharyngeal organ, which is thought to be protrusible, and a dorsal anterior oesophageal gland. Unusual racks are observed in this part, a fact that confirms the deposit feeding behaviour of the worm which has been hypothetized. The serous cells of the oesophageal gland may be the origin of the proteolytic activity detected in the lumen. Intracellular enzymatic activities are detected in the stomach cells. These cells are characterized by numerous iron concretions and polyphagosomes. Comparative elemental analysis of these concretions lead us to think that this digestive segment is a homeostatic organ. The intestine is composed of an absorbant epithelium including enterocytic cells, myocytes, and cells containing zymogenic granules. As much as 90% of ingested protein matter occurs in a water-soluble state (half of it free amino acids, principally glycine) immediately on passing through the anterior part of the gut lumen. In the hindgut, solid faeces are mostly composed of elemental sulfur and are glycine depleted, making them good candidates to form the bulk of the suspended particles found in the waters closely surrounding the worm colonies. The whole gut content contains a high concentration of elemental sulfur. The digestive process of the worm is discussed.
Intersexual variation and factors affecting parental care in Western Bluebirds: a comparison of nestling and fledgling periods
Authors: With Kimberly A. , Balda Russell P.
Published: August 2008

We compared factors affecting parental feeding rates in Western Bluebirds (Sialia mexicana) between the nestling and fledgling periods to evaluate intersexual variation in parental care. Parents did not adjust the frequency of feeding visits between modal (five young) and below-modal (four or less young) broods during the nestling period. The frequency of parental feeding visits also was not significantly affected by offspring age during the nestling period. Males and females exhibited no significant differences in provisioning offspring, although males maintained a constant level of care throughout the nestling period, whereas females increased feeding visits following the brooding period. During the fledgling period, offspring from below-modal broods were fed at higher rates with increasing age than offspring from modal broods. Broods remained together (siblings averaged 8 m apart) within 200 m of the nest box for a week after fledging. As fledglings became more mobile, they would pursue parents while parents were foraging; parental feeding rates thus tended to increase with fledgling age and distance moved from the nest. Offspring sex did not influence parental care during the fledgling period. Both adults fed fledglings, with males taking sole care of fledglings if females initiated a second clutch soon (7–10 days) after fledging of the first brood. Parental feeding rates increased by 60% during the fledgling period compared with the nestling period. No evidence for brood division during the fledgling period was found. Although brood division represents one way of reducing energetic costs attributable to feeding fledglings, Western Bluebirds exhibit an alternate behavior in which the energetics of raising a brood are shared equally between the parents throughout both the nestling and fledgling periods. This is further facilitated by a close association of young during the fledgling period that may reduce energetic costs related to locating and feeding young.
Social organization of reindeer (Rangifer tarandus), with special reference to relationships among females
Authors: Hirotani Akira
Published: August 2008

Approximately 130 individually recognized reindeer, plus unidentified calves, were observed over the course of 9 months from the rutting period to the calving period in Finnish Lapland. The level of association among nonrelated females in resting groups fluctuated with the passage of time. Among related females, only yearling daughters associated significantly with their respective mothers, although coexistence between mothers and yearling daughters was accompanied by antagonism. Two-year-old daughters were next in terms of association with their mothers, whereas daughters of 3 years of age and older rarely associated with their mothers and the level of association decreased to the level observed for nonrelated females. When two herds joined each other, the frequency of antagonistic interactions among foreign individuals was initially quite high. Thereafter, the two herds became united as a new herd within a week or two. A linear dominance hierarchy was found among 90 females that joined the studied herd. Their social rank was correlated with body weight. Thereby, the dominance hierarchy was stably maintained even though the herd itself was a temporary association of individuals. During the nonrutting period, animals segregated themselves by sex. The shedding of male antlers was correlated with drastic changes in ranking.
Shade Tolerance, a Key Plant Feature of Complex Nature and Consequences
Authors: Valladares Fernando , Niinemets Ülo
Published: August 2008

Light gradients are ubiquitous in nature, so all plants are exposed to some degree of shade during their lifetime. The minimum light required for survival, shade tolerance, is a crucial life-history trait that plays a major role in plant community dynamics. There is consensus on the suites of traits that influence shade tolerance, but debate over the relative importance of traits maximizing photosynthetic carbon gain in low light versus those minimizing losses. Shade tolerance is influenced by plant ontogeny and by numerous biotic and abiotic factors. Although phenotypic plasticity tends to be low in shade-tolerant species (e.g., scant elongation in low light), plasticity for certain traits, particularly for morphological features optimizing light capture, can be high. Understanding differential competitive potentials among co-occurring species mediated by shade tolerance is critical to predict ecosystem responses to global change drivers such as elevated CO2, climate change and the spread of invasive species.
Centuries of Human-Driven Change in Salt Marsh Ecosystems
Authors: Gedan K. Bromberg , Silliman B.R. , Bertness M.D.
Published: August 2008

Salt marshes are among the most abundant, fertile, and accessible coastal habitats on earth, and they provide more ecosystem services to coastal populations than any other environment. Since the Middle Ages, humans have manipulated salt marshes at a grand scale, altering species composition, distribution, and ecosystem function. Here, we review historic and contemporary human activities in marsh ecosystems—exploitation of plant products; conversion to farmland, salt works, and urban land; introduction of non-native species; alteration of coastal hydrology; and metal and nutrient pollution. Unexpectedly, diverse types of impacts can have a similar consequence, turning salt marsh food webs upside down, dramatically increasing top down control. Of the various impacts, invasive species, runaway consumer effects, and sea level rise represent the greatest threats to salt marsh ecosystems. We conclude that the best way to protect salt marshes and the services they provide is through the integrated approach of ecosystem-based management.
Detrimental effects of reloading recovery on force, shortening velocity, and power of soleus muscles from hindlimb-unloaded rats
Authors: Widrick J. J. , Maddalozzo G. F. , Hu H. , Herron J. C. , Iwaniec U. T. , Turner R. T.
Published: August 2008

To better understand how atrophied muscles recover from prolonged nonweight-bearing, we studied soleus muscles (in vitro at optimal length) from female rats subjected to normal weight bearing (WB), 15 days of hindlimb unloading (HU), or 15 days HU followed by 9 days of weight bearing reloading (HU-R). HU reduced peak tetanic force (Po), increased maximal shortening velocity (Vmax), and lowered peak power/muscle volume. Nine days of reloading failed to improve Po, while depressing Vmaxand intrinsic power below WB levels. These functional changes appeared intracellular in origin as HU-induced reductions in soleus mass, fiber cross-sectional area, and physiological cross-sectional area were partially or completely restored by reloading. We calculated that HU-induced reductions in soleus fiber length were of sufficient magnitude to overextend sarcomeres onto the descending limb of their length-tension relationship upon the resumption of WB activity. In conclusion, the force, shortening velocity, and power deficits observed after 9 days of reloading are consistent with contraction-induced damage to the soleus. HU-induced reductions in fiber length indicate that sarcomere hyperextension upon the resumption of weight-bearing activity may be an important mechanism underlying this response.
Maternal infection and fever during late gestation are associated with altered synaptic transmission in the hippocampus of juvenile offspring rats
Authors: Lowe Germaine C. , Luheshi Giamal N. , Williams Sylvain
Published: August 2008

Prenatal exposure to infection is known to affect brain development and has been linked to increased risk for schizophrenia. The goal of this study was to investigate whether maternal infection and associated fever near term disrupts synaptic transmission in the hippocampus of the offspring. We used LPS to mimic bacterial infection and trigger the maternal inflammatory response in near-term rats. LPS was administered to rats on embryonic days 15 and 16 and hippocampal synaptic transmission was evaluated in the offspring on postnatal days 20–25. Only offspring from rats that showed a fever in response to LPS were tested. Schaffer collateral-evoked field excitatory postsynaptic potentials (fEPSPs) and fiber volleys in CA1 of hippocampal slices appeared smaller in offspring from the LPS group compared with controls, but, when the fEPSPs were normalized to the amplitude of fiber volleys, they were larger in the LPS group. In addition, intrinsic excitability of CA1 pyramidal neurons was heightened, as antidromic field responses in the LPS group were greater than those from control. Short-, but not long-term plasticity was impaired since paired-pulse facilitation of the fEPSP was attenuated in the LPS group, whereas no differences in long-term potentiation were noted. These results suggest that LPS-induced inflammation during pregnancy produces in the offspring a reduction in presynaptic input to CA1 with compensatory enhancements in postsynaptic glutamatergic response and pyramidal cell excitability. Neurodevelopmental disruption triggered by prenatal infection can have profound effects on hippocampal synaptic transmission, likely contributing to the memory and cognitive deficits observed in schizophrenia.
Identification of cold-shock protein RBM3 as a possible regulator of skeletal muscle size through expression profiling
Authors: Dupont-Versteegden Esther E. , Nagarajan Radhakrishnan , Beggs Marjorie L. , Bearden Edward D. , Simpson Pippa M. , Peterson Charlotte A.
Published: August 2008

Changes in gene expression associated with skeletal muscle atrophy due to aging are distinct from those due to disuse, suggesting that the response of old muscle to inactivity may be altered. The goal of this study was to identify changes in muscle gene expression that may contribute to loss of adaptability of old muscle. Muscle atrophy was induced in young adult (6-mo) and old (32-mo) male Brown Norway/F344 rats by 2 wk of hindlimb suspension (HS), and soleus muscles were analyzed by cDNA microarrays. Overall, similar changes in gene expression with HS were observed in young and old muscles for genes encoding proteins involved in protein folding (heat shock proteins), muscle structure, and contraction, extracellular matrix, and nucleic acid binding. More genes encoding transport and receptor proteins were differentially expressed in the soleus muscle from young rats, while in soleus muscle from old rats more genes that encoded ribosomal proteins were upregulated. The gene encoding the cold-shock protein RNA-binding motif protein-3 (RBM3) was induced most highly with HS in muscle from old rats, verified by real-time RT-PCR, while no difference with age was observed. The cold-inducible RNA-binding protein (Cirp) gene was also overexpressed with HS, whereas cold-shock protein Y-box-binding protein-1 was not. A time course analysis of RBM3 mRNA abundance during HS showed that upregulation occurred after apoptotic nuclei and markers of protein degradation increased. We conclude that a cold-shock response may be part of a compensatory mechanism in muscles undergoing atrophy to preserve remaining muscle mass and that RBM3 may be a therapeutic target to prevent muscle loss.
The love of a lifetime: 5-HT in the cardiovascular system
Authors: Watts Stephanie W.
Published: August 2008

Serotonin [5-hydroxytryptamine (5-HT)] is an amine made from the essential amino acid tryptophan. 5-HT serves numerous functions in the body, including mood, satiety, and gastrointestinal function. Less understood is the role 5-HT plays in the cardiovascular system, although 5-HT receptors have been localized to every important cardiovascular organ and 5-HT-induced changes in physiological function attributed to activation of these receptors. This manuscript relates a few scientific stories that test the idea that 5-HT is important to the control of normal vascular tone, more so in the hypertensive condition. Currently, our laboratory is faced with two different lines of experimentation from which one could draw vastly different conclusions as to the ability of 5-HT to modify endogenous vascular tone and blood pressure. Studies point to 5-HT being important in maintaining high blood pressure, but other studies solidly support the ability of 5-HT to reduce elevated blood pressure. This work underscores that our knowledge of the functions of 5-HT in the cardiovascular system is significantly incomplete. As such, this field is an exciting one in which to be, because there are superb questions to be asked.
Treatment with pyrrolidine dithiocarbamate improves proteinuria, oxidative stress, and glomerular hypertension in overload proteinuria
Authors: Tapia Edilia , Sánchez-González Dolores J. , Medina-Campos Omar N. , Soto Virgilia , Ávila-Casado Carmen , Martínez-Martínez Claudia M. , Johnson Richard J. , Rodríguez-Iturbe Bernardo , Pedraza-Chaverrí José , Franco Martha , Sánchez-Lozada Laura G.
Published: August 2008

We evaluated whether the blockade of the proinflammatory transcription factor NF-κB would modify the oxidative stress, inflammation, and structural and hemodynamic alterations found in the kidney as a result of massive proteinuria. Twenty male Sprague-Dawley rats were injected with 2 g of BSA intraperitoneally daily for 2 wk. Ten of them received in addition the inhibitor of NF-κB activation pyrrolidine dithiocarbamate (PDTC; 200 mg·kg−1·day−1sc) and the rest received vehicle. Seven rats that received intraperitoneal saline were used as controls. Glomerular hemodynamics were studied after 14 days. Markers of oxidative stress (NF-κB subunit p65+ cells, 3-nitrotyrosine, and 4-hydroxynonenal), inflammation (cortical CD68+ cells and NOS-II), and afferent arteriole damage were assessed by immunohistochemistry and morphometry. Activity of antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase was evaluated in renal cortex and medulla. Albumin overload induced massive proteinuria, oxidative stress with reduced activity of antioxidant enzymes, NF-κB activation, inflammatory cell infiltration, a significant presence of proteinaceous casts, systemic and glomerular hypertension, as well as arteriolar remodeling. Treatment with PDTC prevented or improved all of these findings. In this model of nephrotic syndrome, we demonstrate a key role for oxidative stress and inflammation in causing systemic and glomerular hypertension and proteinuria. Oxidative stress and inflammation may have a key role in accelerating renal injury associated with intense proteinuria.
Interleukin-18 binding protein transgenic mice are protected against ischemic acute kidney injury
Authors: He Zhibin , Lu Lawrence , Altmann Christopher , Hoke Thomas S. , Ljubanovic Danica , Jani Alkesh , Dinarello Charles A. , Faubel Sarah , Edelstein Charles L.
Published: August 2008

IL-18 function is neutralized in IL-18 binding protein transgenic (IL-18BP Tg) mice. First, we determined whether IL-18BP Tg mice are protected against ischemic acute kidney injury (AKI). Ischemic AKI was induced by bilateral renal pedicle clamping. IL-18BP Tg mice were functionally and histologically protected against ischemic AKI as determined by blood urea nitrogen, serum creatinine, and acute tubular necrosis score. We have demonstrated that the injurious effect of IL-18 in the kidney is independent of neutrophils and lymphocytes. Thus the effect of IL-18 inhibition on renal macrophage infiltration was determined. The number of macrophages was significantly reduced in IL-18BP Tg compared with wild-type kidneys. To determine the cytokines and chemokines that are dependent on IL-18, we performed flow cytometry based assays. Multiple chemokines/cytokines, IL-3, IL-6, IL-15, IL-18, leukemia inhibitory factor, macrophage colony-stimulating factor, macrophage inflammatory protein-2, granulocyte-macrophage colony-stimulating factor, and monocyte chemotactic protein-1 were significantly increased in AKI vs. sham kidneys. Only CXCL1 (also known as KC or IL-8) was significantly increased in AKI vs. sham kidneys and significantly reduced in IL-18BP Tg AKI vs. wild-type AKI kidneys. To determine whether macrophages are the source of CXCL1 in the kidney, we depleted macrophages with liposomal encapsulated clodronate. CXCL1 was significantly decreased in macrophage-depleted vs. control AKI mice. In summary, in ischemic AKI in mice, 1) IL-18BP Tg mice are functionally and histologically protected, 2) macrophage infiltration in the kidney and CXCL1 are significantly reduced in IL-18BP Tg mice, and 3) macrophage depletion significantly reduces CXCL1 in the kidney. In conclusion, protection against ischemic AKI in IL-18BP Tg mice is associated with less macrophage infiltration and less production of CXCL1 in the kidney.
Effects of terlipressin on the aquaretic system: evidence of antidiuretic effects
Authors: Krag Aleksander , Bendtsen Flemming , Pedersen Erling Bjerregaard , Holstein-Rathlou Niels-Henrik , Møller Søren
Published: August 2008

The vasopressin analog terlipressin is believed to cause vasoconstriction selectively by V1receptor stimulation. However, a possible antidiuretic effect by V2receptor stimulation has never been ruled out. Twenty-two patients with ascites, including seven with refractory ascites, were included. The subjects were studied during a 400 ml/h oral water load before and after infusion of 2 mg of terlipressin (18 patients) or placebo infusion (4 patients). Effects on the V2receptors were assessed by evaluating aquaporin (AQP)2 excretion, free water clearance (C[Formula: see text]), urine osmolality (Uosm), and fractional distal water excretion (DFeH2O). After terlipressin the excretion of AQP2 increased by 89% [144 ng/mmol creatinine, 95% confidence interval (CI) 73–214 ng/mmol creatinine, P = 0.001]. C[Formula: see text] decreased 1.05 ml/min (from 0.17 to −0.89 ml/min, P = 0.001), and DFeH2O decreased 37% (19 vs. 12; 95% CI 2–11, P = 0.01). Uosmincreased by 27% (93 mosmol/kgH2O, 95% CI 23–164 mosmol/kgH2O, P = 0.02). Plasma sodium decreased 1.1 mmol/l ( P < 0.01). An increase in AQP2 excretion and a decrease in C[Formula: see text] and distal water excretion after terlipressin despite water loading is a clear indication of activation of the antidiuretic system (V2receptor effect).
Computational Approach of Dielectric Permitivities in BaTiO3—Epoxy Composites
Authors: Ramajo L. , Reboredo M. , Santiago D. , Castro M. , Ramajo D.
Published: August 2008

A numerical approach using a finite element method (FEM) was performed in order to determine the dielectric constant (ε') of BaTiO 3—epoxy composites. In order to diminish computational resources and analyse simple models, composite topology was represented by periodic structures based on FCC configurations, but introducing novel packaging protocols, defining the way composites are filled as particle concentration is increased. The dielectric response of these anisotropic and periodic structures was mathematically represented through a quasi-static approximation using the Laplace equation. The amount of inclusions was varied in order to represent diluted and concentrated systems and structures were assessed for the whole feasible range of volume fractions. The numerical results were compared with experimental data concluding that only packaging protocols that consider higher particle—particle interaction are suitable to represent the dielectric behavior of concentrated-composite materials.
Noticing Noticing
Authors: Rosaen Cheryl L. , Lundeberg Mary , Cooper Marjorie , Fritzen Anny , Terpstra Marjorie
Published: August 2008

This study investigated the following question: To what extent and in what ways might using video help interns reflect on their discussion-based teaching in a more complex manner than when they use memory-based written reflection? Three elementary interns participated in the study. Findings suggest that video-supported reflection enabled interns to write more specific (vs. general) comments about their teaching than writing from memory, shift the content of the reflections from a focus on classroom management in memory-based reflections to a focus on instruction when video was available, and focus less on themselves and more on children when they reflected on video clips of their teaching. The power of video-based reflection to help interns revisit, notice, and investigate how they facilitate classroom discussions is considered.
“Culture populaire et religion”: Approches théoriques de la religiosité populaire au sein des cultures populaires latino-américaines
Authors: Ameigeiras Aldo
Published: August 2008

Les questions théoriques portant sur les cultures populaires et leur relation avec les religions ont traversé différentes phases, suivant les repositionnements des diverses perspectives en vigueur dans les sciences sociales. L'auteur s'intéresse ici à ce phénomène à partir de quelques perspectives qui ont dernièrement souligné la nécessité de refondre les catégories d'analyse du sacré, en particulier en prenant en compte la singularité des cultures populaires latino-américaines.
Hope for Healing: The Mobilization of Interest in Three Types of Religious Healing in the Netherlands since 1850
Authors: Vellenga Sipco J.
Published: August 2008

The author examines the development of the popularity of religious healing in the Netherlands since 1850 and the factors that contribute to its continuation. He focuses upon three traditions: devotional healing in Roman Catholicism, charismatic healing in Pentecostalism and paranormal healing in western esotericism. From 1850 to about 1965, interest in making a pilgrimage to holy places of healing showed a strong increase, while the number of participants in faith-healing and esoteric healing remained small. Since then, this situation has been completely reversed. Starting from a mobilization approach, the author shows that this development is linked to contextual (market and demand) factors and institutional (organization and supply) factors. It is argued that the continuation of religious healing practices challenges established religious as well as medical institutions to approach patients more integrally as whole persons.
The Nature of Spirituality among Young People in Australia and Thailand
Authors: Hughes Philip , Suwanbubbha Parichart , Chaisri Janram
Published: August 2008

Eighty interviews with Thai young people and 283 interviews with Australian young people revealed that there were similarities and differences in the ways they related to religion. All Thai young people identified with a religion and considered religion important as a basis for morality. In contrast, many Australian young people neither identified with religion nor considered it important. In both contexts, many young people occasionally or never participated in public or personal religious practices. While many Thai young people were sceptical about some traditional religious beliefs, it was common among Australian young people to see beliefs as something they constructed personally using traditions as resources. In Thailand, religion remains a key part of the publicly accepted culture, while in Australia it has become a personal “lifestyle” option. The differences suggest that religion plays different social roles and takes different forms in different cultural contexts.
Risk for Disciplinary Infractions Among Incarcerated Male Youths
Authors: Mcreynolds Larkin S. , Wasserman Gail A.
Published: August 2008

The authors examine the contribution of disorder to disciplinary infractions among incarcerated male youths. In all, 176 youths recently admitted to a secure assessment center self-administered the Voice Diagnostic Interview Schedule for Children—IV. Demographic and justice-related data were abstracted from official records. Younger boys, minority youths, and those who stayed longer were found to infract more. Controlling for these factors, infraction risk was significantly lowered by anxiety, affective disorder, disruptive behavior, or substance use disorder (vs. no disorder), as well as more or more types of disorder. Youths with mental health concerns were less likely to infract. Results highlight the importance of employing systematic and universal screening rather than relying on observable management problems to identify mental health needs.
Juvenile Inmates in an Adult Prison System
Authors: Kuanliang Attapol , Sorensen Jon R. , Cunningham Mark D.
Published: August 2008

Rates of disciplinary misconduct and violence among juvenile male inmates ( N = 703) admitted to a state prison system from 1998 to 2002 are retrospectively examined. The prevalence and frequency of prison misconduct and violence are higher among juveniles than comparison groups of nearest age youthful adults ( N = 3,640) and adult prisoners generally ( N = 33,114), and this disparity between juvenile and adult inmates increases along with the severity of violence. This relationship is found to hold true even when other known correlates of prison violence are considered. In a logistic regression model that included educational level, gang affiliation, offense of conviction, and sentence length, age is found to be the most consistent and strongest determinant of prison violence, with those younger than 18 at entrance to prison being far more likely than adults to be involved in various levels of prison misconduct and violence.
Controlling the Walking Speed in Limit Cycle Walking
Authors: Hobbelen D.G.E. , Wisse M.
Published: August 2008

“Limit Cycle Walking” is a relatively new paradigm for the design and control of two-legged walking robots. It states that achieving stable periodic gait is possible without locally stabilizing the walking trajectory at every instant in time, as is traditionally done in most walking robots. Well-known examples of Limit Cycle Walkers are the Passive Dynamic Walkers, but recently there are also many actuated Limit Cycle Walkers. Limit Cycle Walkers generally use less energy than other existing bipeds, but thus far they have not been as versatile. This paper focuses on one aspect of versatility: walking speed. We study how walking speed can be varied, which way is energetically beneficial and how walking speed affects a walker's ability to handle disturbances (that is, disturbance rejection). The study is performed using one prototype and one simulation model. The speed of these two walkers is adapted by changing three parameters: the amount of ankle push-off, upper body pitch and step length. The study has resulted in four conclusions. (1) Steady-state speeds between 0.24 and 0.68 m s-1 (for a 0.6 m leg length) were obtained, with loss of stability determining the lower limit and actuation limits determining the upper limit. This result shows the applicability of Limit Cycle Walking for versatile walking machines. (2) For any speed, powering the gait by leaning the body forward costs less energy than using ankle push-off. (3) In contrast to the apparent tradeoff between speed and stability in traditional walking robots, in Limit Cycle Walking we find that increasing the walking speed, independent of how this is done, automatically results in an increasing disturbance rejection. (4) A combination of feedforward actuation adjustment and step-to-step feedback from walking speed shows that it is possible to change walking speed in only a few steps and maintain a desired speed when performing tasks such as carrying loads and walking on slopes. In particular, this fourth conclusion underlines the applicability of the concept of Limit Cycle Walking for versatile two-legged walking machines.