bluuebunny/crossref_metadata_2025 huggingface dataset:
Living dangerously: an orb-weaving spider potentially exploits an ant-acacia mutualism for enemy-free space
Authors: Styrsky John
Published: November 2010

Exploitation of commodities exchanged in mutualistic interactions has been broadly documented, but typically involve the exploitation of a reward rather than a service. Further, examples of exploiter species are extremely rare in certain groups of animals, such as spiders. In 2008 and 2009, we investigated the potential exploitation by an orb-weaving spider (Eustala oblonga) of the plant protection services of ants on an ant-defended acacia (Acacia melanocerus) in lowland rainforest in central Panama. Despite vigorous patrolling of the acacias by the very pugnacious ants (Pseudomyrmex satanicus), we observed the spiders constructing orb webs among the branches at night and resting quietly during the day on the leaves or at the bases of the thorns in which the ants live and raise their brood. E. oblonga spiders occurred in fairly high densities on A. melanocerus, but were very rarely observed on A. melanocerus plants that were no longer occupied by P. satanicus or on other species of plants in the forest understory. Further, the spiders were never observed attacking the ants. To test the hypothesis that E. oblonga inhabits the ant-defended acacias for protection against would-be spider predators, we removed entire ant colonies from acacias by injecting tiny amounts of a dilute insecticide into all hollow thorns serving as domatia for the ants, killing the ants within 30 minutes. We then compared spider abundance for six weeks on the acacias without ant colonies to spider abundance on acacias with intact colonies of defending ants. During the weekly ant censuses, we also recorded the presence and abundance of any other invertebrate or vertebrate species on the experimental and control acacias, particularly noting any potential predators of the spiders. Spider abundance did not vary between the experimental and control plants during the first two weeks after the initiation of the experiment, but then decreased significantly on the acacias without ant colonies over the remaining four weeks of sampling. This decrease in spider abundance is not likely to be attributed to application of the dilute insecticide because spiders were not immediately affected and the insecticide degrades within 24 hours of application. Other organisms increased in abundance over time on the experimental acacias relative to the control acacias, including predatory insects and other potential spider predators. These results suggest that ant protection of A. melanocerus also protects the spiders, thus, supporting the hypothesis that E. oblonga exploits the ant-acacia mutualism for enemy-free space.
Evolution is Viral: The Theory of Collective Discontinuous Evolution
Authors: Gershteyn Mikhail L. , Gershteyn Iosif
Published: November 2010

Herein will be discussed the problems associated with the origin of species according to Darwinist processes of individual mutations. We will argue that individual mutations cannot be the driving force of species origination. A far more probable explanation is a process of collective mutation that affects numerous individuals near simultaneously akin to an infectious disease. These types of mutations might be precipitated by viruses which would create a discontinuous leap into another species. Such a mechanism also sheds light on the increased rate of evolution observed currently.
Evolutionary trade-offs among decomposers may constrain responses to nitrogen
Authors: Treseder Kathleen , Kivlin Stephanie , Hawkes Christine
Published: November 2010

We tested the extent to which evolutionary trade-offs among species traits might constrain the responses of different functional groups of decomposers to global change. Specifically, we hypothesized that bacteria targeting large recalcitrant compounds require relatively high levels of nitrogen (N) availability to support the construction costs of requisite extracellular and carrier enzymes. Conversely, bacteria adapted to N-poor environments may invest scarce resources in enzymes targeting organic N instead of recalcitrant carbon. We cross-referenced carbon substrate use profiles (from Biolog plates), functional genes from published bacterial genomes, the global ocean sampling (GOS) expedition, and a global synthesis of environmental DNA sequences of bacteria in soils. Altogether, 628 taxa were assessed. We defined recalcitrant users as those that used a larger proportion of cyclic compounds (based on Biolog assays). Recalcitrant users were detected in ocean waters with higher nitrate concentrations (phylogenetic independent contrasts, r = 0.888, P < 0.001), and they contained a greater proportion of genes related to inorganic N uptake and transformation (r = 0.665, P < 0.001) than did labile users. Compared to recalcitrant users, labile users targeted more organic N compounds in Biolog plates (r = -0.484, P < 0.001), carried a greater proportion of genes related to the use of organic N (r = -0.203, P < 0.001), and fewer genes for complex organic carbon compounds (r = 0.957, P < 0.001). Taxa that preferred organic N sources were more common in higher latitude soils than in lower latitude soils (r = 0.850, P < 0.001), which is consistent with the paradigm that N-limitation is stronger at higher latitudes. Altogether, evolutionary trade-offs may limit recalcitrant users to habitats with higher N availability. As a potential consequence, anthropogenic N enrichment may lead to the breakdown of recalcitrant organic compounds and a rise in the release of carbon to the atmosphere.
Electroluminescence from AlN nanowires grown on p-SiC substrate
Authors: Yang H. Y. , Yu S. F. , Hui Y. Y. , Lau S. P.
Published: November 2010

Aluminum nitride (AlN) nanowires were prepared by the carbothermal reduction method. A heterojunction light-emitting diode (LED) was fabricated by depositing randomly aligned AlN nanowires onto p-type 4H–SiC substrate. When a forward bias voltage greater than 8 V was applied to the LED, a broad band emission peaked at 417 nm could be observed. The peak deconvolution revealed four emission peaks at ∼400, 420, 468, and 525 nm. These emission peaks may be attributed to the radiative recombination between electrons from trap-level states and holes from the valence band of the AlN nanowires.
Crystal defect topography of Stranski–Krastanow quantum dots by atomic force microscopy
Authors: Gradkowski K. , Sadler T. C. , Mereni L. O. , Dimastrodonato V. , Parbrook P. J. , Huyet G. , Pelucchi E.
Published: November 2010

We demonstrate a technique to monitor the defect density in capped quantum dot (QD) structures by performing an atomic force microscopy (AFM) of the final surface. Using this method we are able to correlate their density with the optical properties of the dot structures grown at different temperatures. Parallel transmission electron microscopy analysis shows that the AFM features are directly correlated with the density of stacking faults that originate from abnormally large dots. The technique is rapid and noninvasive making it an ideal diagnostic tool for optimizing the parameters of practical QD-based devices.
Selective translocation of Ca
2+
/calmodulin protein kinase IIα (CaMKIIα) to inhibitory synapses
Authors: Marsden Kurt C. , Shemesh Adi , Bayer K. Ulrich , Carroll Reed C.
Published: November 2010

Ca
2+
/Calmodulin protein kinase IIα (CaMKIIα) has a central role in regulating neuronal excitability. It is well established that CaMKIIα translocates to excitatory synapses following strong glutamatergic stimuli that induce NMDA-receptor (NMDAR)-dependent long-term potentiation in CA1 hippocampal neurons. We now show that CaMKIIα translocates to inhibitory but not excitatory synapses in response to more moderate NMDAR-activating stimuli that trigger GABA
A
-receptor (GABA
A
R) insertion and enhance inhibitory transmission. Such moderate NMDAR activation causes Thr286 autophosphorylation of CaMKIIα, which our results demonstrate is necessary and sufficient, under basal conditions, to localize CaMKIIα at inhibitory synapses and enhance surface GABA
A
R expression. Although stronger glutamatergic stimulation coupled to AMPA receptor insertion also elicits Thr286 autophosphorylation, accumulation of CaMKIIα at inhibitory synapses is prevented under these conditions by the phosphatase calcineurin. This preferential targeting of CaMKIIα to glutamatergic or GABAergic synapses provides neurons with a mechanism whereby activity can selectively potentiate excitation or inhibition through a single kinase mediator.
Copper- and copper–
N
-heterocyclic carbene-catalyzed C─H activating carboxylation of terminal alkynes with CO
2
at ambient conditions
Authors: Yu Dingyi , Zhang Yugen
Published: November 2010

The use of carbon dioxide as a renewable and environmentally friendly source of carbon in organic synthesis is a highly attractive approach, but its real world applications remain a great challenge. The major obstacles for commercialization of most current protocols are their low catalytic performances, harsh reaction conditions, and limited substrate scope. It is important to develop new reactions and new protocols for CO
2
transformations at mild conditions and in cost-efficient ways. Herein, a copper-catalyzed and copper–
N
-heterocyclic carbene-cocatalyzed transformation of CO
2
to carboxylic acids via C─H bond activation of terminal alkynes with or without base additives is reported. Various propiolic acids were synthesized in good to excellent yields under ambient conditions without consumption of any organometallic or organic reagent additives. This system has a wide scope of substrates and functional group tolerances and provides a powerful tool for the synthesis of highly functionalized propiolic acids. This catalytic system is a simple and economically viable protocol with great potential in practical applications.
G1 arrest and differentiation can occur independently of Rb family function
Authors: Wirt Stacey E. , Adler Adam S. , Gebala Véronique , Weimann James M. , Schaffer Bethany E. , Saddic Louis A. , Viatour Patrick , Vogel Hannes , Chang Howard Y. , Meissner Alex , Sage Julien
Published: November 2010

The ability of progenitor cells to exit the cell cycle is essential for proper embryonic development and homeostasis, but the mechanisms governing cell cycle exit are still not fully understood. Here, we tested the requirement for the retinoblastoma (Rb) protein and its family members p107 and p130 in G0/G1 arrest and differentiation in mammalian cells. We found that Rb family triple knockout (TKO) mouse embryos survive until days 9–11 of gestation. Strikingly, some TKO cells, including in epithelial and neural lineages, are able to exit the cell cycle in G0/G1 and differentiate in teratomas and in culture. This ability of TKO cells to arrest in G0/G1 is associated with the repression of key E2F target genes. Thus, G1 arrest is not always dependent on Rb family members, which illustrates the robustness of cell cycle regulatory networks during differentiation and allows for the identification of candidate pathways to inhibit the expansion of cancer cells with mutations in the Rb pathway.
Distinct roles of septins in cytokinesis: SEPT9 mediates midbody abscission
Authors: Estey Mathew P. , Di Ciano-Oliveira Caterina , Froese Carol D. , Bejide Margaret T. , Trimble William S.
Published: November 2010

Septins are a family of GTP-binding proteins implicated in mammalian cell division. Most studies examining the role of septins in this process have treated the family as a whole, thus neglecting the possibility that individual members may have diverse functions. To address this, we individually depleted each septin family member expressed in HeLa cells by siRNA and assayed for defects in cell division by immunofluorescence and time-lapse microscopy. Depletion of SEPT2, SEPT7, and SEPT11 causes defects in the early stages of cytokinesis, ultimately resulting in binucleation. In sharp contrast, SEPT9 is dispensable for the early stages of cell division, but is critical for the final separation of daughter cells. Rescue experiments indicate that SEPT9 isoforms containing the N-terminal region are sufficient to drive cytokinesis. We demonstrate that SEPT9 mediates the localization of the vesicle-tethering exocyst complex to the midbody, providing mechanistic insight into the role of SEPT9 during abscission.
Brief alcohol interventions for mandated college students: comparison of face‐to‐face counseling and computer‐delivered interventions
Authors: Carey Kate B. , Carey Michael P. , Henson James M. , Maisto Stephen A. , DeMartini Kelly S.
Published: November 2010

Aims  College students who violate alcohol policies are often mandated to participate in alcohol‐related interventions. This study investigated (i) whether such interventions reduced drinking beyond the sanction alone, (ii) whether a brief motivational intervention (BMI) was more efficacious than two computer‐delivered interventions (CDIs) and (iii) whether intervention response differed by gender.

Design  Randomized controlled trial with four conditions [brief motivation interventions (BMI), Alcohol 101 Plus™, Alcohol Edu for Sanctions®, delayed control] and four assessments (baseline, 1, 6 and 12 months).

Setting  Private residential university in the United States.

Participants  Students (n = 677; 64% male) who had violated campus alcohol policies and were sanctioned to participate in a risk reduction program.

Measurements  Consumption (drinks per heaviest and typical week, heavy drinking frequency, peak and typical blood alcohol concentration), alcohol problems and recidivism.

Findings  Piecewise latent growth models characterized short‐term (1‐month) and longer‐term (1–12 months) change. Female but not male students reduced drinking and problems in the control condition. Males reduced drinking and problems after all interventions relative to control, but did not maintain these gains. Females reduced drinking to a greater extent after a BMI than after either CDI, and maintained reductions relative to baseline across the follow‐up year. No differences in recidivism were found.

Conclusions  Male and female students responded differently to sanctions for alcohol violations and to risk reduction interventions. BMIs optimized outcomes for both genders. Male students improved after all interventions, but female students improved less after CDIs than after BMI. Intervention effects decayed over time, especially for males.
How integument colour reflects its carotenoid content: a stickleback’s perspective
Authors: Pike Thomas W. , Bjerkeng Bjørn , Blount Jonathan D. , Lindström Jan , Metcalfe Neil B.
Published: November 2010

1. Carotenoid‐based signals typically vary in both the total concentration of carotenoids deposited and the relative quantities of different constituent carotenoids. As these constituents often have differing spectral properties, the relative and absolute concentrations of different carotenoids deposited in a signal can significantly affect the spectrum of light reflected. A critical but rarely tested assumption of hypotheses concerning the information content of carotenoid‐based signals is that their colour directly reveals the concentration and composition of constituent carotenoids to intended recipients. Most previous studies have attempted to address this question using either photographic techniques or by analysing recorded reflectance spectra, neither of which take into account the specific properties of the receiver’s visual system.

2. Here, we use psychophysical models of the visual system of three‐spined sticklebacks (Gasterosteus aculeatus) to estimate their sensitivity to variation in the concentration and relative abundance of constituent carotenoids of males’ carotenoid‐based sexual signals.

3. We demonstrate that sticklebacks are acutely sensitive to variation in both the total concentration of carotenoids in the signal and the relative proportion of its constituents, and that the accuracy of these assessments is largely unaffected by the presence or absence of ultraviolet radiation in the illuminant. We discuss these findings in relation to the evolution, maintenance and information content of carotenoid‐based sexual signals.
Comparison between intraluminal multiple electric impedance measurement and manometry in the human oesophagus
Authors: Frieling Thomas , HERMANN S. , KUHLBUSCH R. , ENCK P. , SILNY J. , LÜBKE H. J. , STROHMEYER G. , HAEUSSINGER D.
Published: November 2010

Abstract Conventional oesophageal manometry and intraluminal electrical impedance measurement were simultaneously applied in eight healthy volunteers to study the effect of wet and semisolid bolus viscosities on oesophageal motility and bolus transit. Contraction front velocity measured by electrical impedance and manometry were identical for wet and semisolid swallows and highly associated. Bolus front velocity as measured by electrical impedance was significantly faster than contraction front velocity in both wet and semisolid swallows. Bolus front velocity during semisolid swallows was significantly slower compared to wet swallows. It is concluded that intraluminal electrical impedance measurement is a reliable technique to detect oesophageal motility as well as to differentiate between transit of wet and semisolid bolus consistencies.
Luteinizing hormone and human chorionic gonadotropin fragment the migrating myoelectric complex in rat small intestine
Authors: DUCKER T. E. , BOSS J. W. , ALTUG S. A. , MEHRABIAN H. , DEKERATRY D. R. , CLENCH M. H. , Mathias John R.
Published: November 2010

Abstract We hypothesized that sex hormones may affect motility disorders because these diseases occur more often in women than in men, and symptoms often occur or worsen after ovulation. Luteinizing hormone (LH) is predominantly secreted by the anterior pituitary midway through the menstrual cycle; it results in the development of the corpus luteum. LH levels also increase after bilateral gonadectomy. LH and human chorionic gonadotropin (hCG) bind to the same receptor, but rats lack hCG. To assess how LH and hCG influence myoelectric activity of the small intestine and to test the specificity of the LH receptor, we implanted electrodes on the jejunum of female rats. LH (0.1 or 0.5 NIH units) was administered intraperitoneally to intact and gonadectomized rats and 0.5 NIH units to rats that had been both hypophysectomized and gonadectomized; intact animals were treated with 100 units USP of hCG. Recordings were made with the rats in fasted and in fed states, and their intestinal motility was analysed. The most striking effects of LH, hypophysectomy, and hCG were the same: phase III of the migrating myoelectric complex was markedly fragmented and its duration lengthened (P < 0.0001). Gonadectomy alone and gonadectomy with hypophysectomy also increased fragmentation and phase III duration (P < 0.01 or better). LH receptors respond similarly to LH and hCG, and both hormones alter myoelectric activity of the rat small intestine in comparable ways.
Electrophysiology of porcine myenteric neurons revealed after vital staining of their cell bodies. A preliminary report
Authors: CORNELISSEN W. , Timmermans Jean‐Pierre , VAN BOGAERT P.‐P. , SCHEUERMANN D. W.
Published: November 2010

Abstract Due to practical limitations in visualizing and getting access to the ganglionic components of large mammals, electrophysiology of the enteric nervous system has been restricted mainly to small laboratory animals, more particularly the guinea‐pig. The use of the vital dye 4‐(4‐diethylaminostyryl)‐N‐methylpyridinium iodide (4‐Di‐2‐ASP), however, overcomes some of these difficulties. A 20‐min incubation period with this dye, followed by a minimum period of 4 h in Krebs solution, suffices to stain the neuronal cell bodies, permitting selection of a neuron and positioning of the microelectrode for impalement and recording. The method has been applied to pig ileum and guinea‐pig large and small bowel myenteric neurons. Impalements of untreated guinea‐pig myenteric neurons were compared with those of 4‐Di‐2‐ASP‐pre‐treated ones. According to our preliminary data, the staining did not suppress the expression of apparently normal electrophysiological activity. Moreover, the procedure permitted impalement and recording of myenteric plexus neurons in pig ileal tissue with a rate of success equalling blind impalement on guineapig tissue. In contrast with formerly published results whereby staining of the neuronal cell bodies only occurred when the cells had been chemically damaged, our experiments suggest a possible correlation between fluorescence and cell viability.
Evaluation of gastric antral motor performance in patients with dysmotility‐like dyspepsia using real‐time high‐resolution ultrasound
Authors: AHLUWALIA N. K. , THOMPSON D. G. , MAMTORA H. , HINDLE J.
Published: November 2010

Abstract Although manometric antral hypomotility and delayed gastric emptying have been reported separately in patients with dyspepsia, relationships between symptoms, antral contractility and emptying rate have not been sought. The present study therefore aimed to evaluate, simultaneously, gastric antral excursion characteristics and emptying in a sub‐group of patients with severe functional dyspepsia using high‐resolution real‐time ultrasound. The circumference of the relaxed and contracted antrum was measured at 15‐min intervals after ingestion of a 360 mL mixed nutrient meal in 36 chronic dyspepsia patients with symptoms of post‐prandial bloating and epigastric distension, and in 25 healthy volunteers. Antral emptying (measured as the rate of decrease in circumference of the relaxed antrum) was slower in patients than normals (P = 0.02). In both groups, the average values for antral excursion were similar but the range of excursion in patients was significantly wider than in controls (F < 0.001), with 11 patients showing values above, and 8 showing values below the normal range. There was no relationship between antral emptying and antral excursion in either patients or volunteers.

In conclusion, patients with severe functional dyspepsia show a wide range of antral performance characteristics, suggesting not only that the mechanisms responsible for the control of antral motor function are disturbed but also that the cause of the symptoms and the disturbed antral motor function are probably not directly related.
Variations spectroscopiques induites par illumination et par action chimique observées à—196°C dans la chlorophylle a de Porphyridium
Authors: HOARAU J. , LECLERC J.‐C.
Published: November 2010

Spectroscopic Changes in the Chlorophyll a of Porphyridium Induced by Illumination and Chemical Action and Observed at −196°C.

Photo‐oxidation of P700 by 708 nm light can take place under weak intensity (10−6 W × cm−2) when the medium is frozen. Spectral characteristics of “700 nm” and “690 nm” variations are accurately measured. The amplitude of the photoinduced changes of absorption are similar to those induced by chemical action. In the case of Porphyridium, an apparent increase of the extinction power of P700 at −196°C is observed. This fact seems to be due to a diminution of the bandwith of the neighbouring pigments.

Irradiation with red light (685 nm), of a relatively high intensity (10−2 W × cm−2), in the presence of oxygen at −196°C, induces a slight shift (0.5 nm) of the red absorption band maximum towards longer wavelengths. This change is similar to the one promoted by ferricyanide in the dark. The origin and the functional significance of the phenomenon is discussed.
Mesure d'une activité métabolique in vivo. Cas du catabolisme purique chez le Pharbitis nil
Authors: NGUYEN JACQUELINE
Published: November 2010

In vivo measurement of a metabolic activity. — Purine catabolism in Pharbitis nil cotyledons.

To study the influence of light and darkness on the level of purine degradation, an in vivo method of measuring this catabolic pathway has been developed. Cotyledon discs of Pharbitis nil were incubated in an aqueous solution of hypoxanthine‐8‐14C. This purine base was first oxidized by a NAD+ dependent xanthine dehydrogenase. The metabolic flow was expressed either by the quantity of products (xanthine + uric acid + allantoin + allantoic acid) or by the rate of hypoxanthine degradation in the discs. This easy, reproducible and very sensitive technique of measurement has been investigated with respect to several variables including tissue quantity, length of incubation time, hypoxanthine and NAD+ concentrations, and pH.

The quantity of products varied proportionally with the tissue quantity but the catabolic rate was not linked to this. The best conditions of measurement were to incubate discs for at least 60 min in distilled water containing only hypoxanthine‐8‐14C at low concentrations (below 0.25 mM). The values obtained represent the actual in vivo level of the studied metabolic pathway. The NAD+ concentration within the tissue does not seem to be a limiting factor for hypoxanthine degradation, the hypoxanthine concentration itself appears to be the only limiting factor in endogenous purine catabolism.
Influence of Phytohormones on the Response of Cultured Cotton Ovules to (2‐chloroethyl)phosphonic Acid
Authors: STEWART JAMES McD. , HSU CECILIA LEE
Published: November 2010

Callus was induced from the micropylar end of cultured cotton (Gossypium hirsutum L.) ovules by (2‐chloroethyl)phosphonic acid (CEPA). The influence of other phytohormones on the growth of this callus was examined with in vitro culture techniques. Abscisic acid inhibited the callus growth induced by 10−4 M CEPA, but at low concentrations of abscisic acid and CEPA, callus growth was stimulated slightly. Indoleacetic acid inhibited the callus growth at optimum CEPA concentration, but not when the CEPA level was supraoptimum. Kinetin stimulated micropylar callus growth when ovules were obtained from parent plants grown under long, warm days but not when ovules were from plants grown under short days and cooler temperatures. Gibberellic acid (GA) caused the greatest callus response. Increasing concentrations of GA up to 5 × 10−7 M markedly stimulated callus growth while increasing the sensitivity of the tissue to CEPA. In addition to induction and growth of the micropylar callus, combinations of CEPA and GA caused a complete release of normal tissue differentiation in the cotton ovule with rapid proliferation of the entire ovule integument. This is a promising system with which to study hormonal control of tissue differentiation.
Keto Acids in Pollen and Pollen Tubes of Sesbania aegyptica
Authors: MALIK C. P. , SINGH M. B. , SOOD RENUKA
Published: November 2010

Pollen and pollen tubes of Sesbania aegyptica Pers. contain α‐ketoglutaric acid, oxaloacetic acid and pyruvic acid. Changes in the keto acids have been correlated with their corresponding amino acids during different phases of germination. It is suggested that keto acids were readily turned over during the elongation of pollen tubes.
Clinico‐pathological correlates in IgA nephropathy
Authors: CHIANG GSC , WOO KT
Published: November 2010

Summary: There were 2758 biopsies of glomerulonephritis diagnosed in the Department of Pathology in the 20 years from 1976 to 1995. Of these 1893 (76.1%) were of primary glomerulonephritis while 577 (23.2%) were of secondary glomerulonephritis. Immunofluorescence studies were available in 1494 (80%) cases. Predominantly mesangial IgA staining was seen in 49.1% of cases, thus identifying them as IgA nephropathy. Mesangial glomerulonephritis was found in 79.1% of cases whilst 17.7% had sclerotic lesions either focal or global. One hundred and fifty‐one patients were followed up. Of these, 98 (65%) were detected through health screening while 53 (35%) presented with symptoms. Uncontrolled hypertension, proteinuria of more than 2 g, the presence of crescents and glomerulosclerosis on biopsy were unfavourable prognostic factors. Hypertensive patients also had a higher incidence of medial hyperplasia of the blood vessels. However IgA nephropathy is a benign disease with a cumulative renal survival of 91% after 6 years.
Animal models of IgA nephropathy: Formulating therapeutic strategies
Authors: EMANCIPATOR Steven N. , CHINTALACHARUVU Subba R. , BAGHERI Nayer , SCIVITTARO Vincenzo
Published: November 2010

Summary: This review seeks to highlight those aspects of ongoing research with animal models that may facilitate development of effective and perhaps specific therapy of IgAN. Oral immunization is typically accompanied by a predominantly Th2 response; defects in the evolution of this typical response, instigated by cyclophosphamide and/or oestradiol, elicit IgAN in mice. The Th2 cytokines that predominate in orally immunized mice, and in patients with IgAN, promote abnormally glycosylated IgA, similar to the IgA in patients. Immune complexes prepared with IgA antibody bearing altered glycosyl residues show enhanced rates of glomerular uptake and altered rates of clearance from the circulation. When immune responses to infectious pathogens are localized to sites remote from a new infection with a serologically related organism, ‘misdirected’ responses permit pathogen replication and antigen production concomitant with strong host antibody responses. The resultant immune complexes elicit IgAN in mice. Similar ‘misdirected’ immune responses may arise in J chain‐deficient subjects. Improved pharmacologic control of B cell trafficking and/or function could rectify these defects. Correction of deficiency in clearance of IgA immune complexes could benefit patients with secondary IgAN. Finally, manipulation of glomerular haemodynamics and/or production or response to intraglomerular cytokines and growth factors might ameliorate disease or forestall progression to glomerulosclerosis. Animal models have served as a conceptual springboard for a wide variety of clinical investigations, and in turn clinical information has guided the design and goal of experimental investigation. Hopefully, this synergy can continue, ultimately resulting in effective and specific therapy.
Human immunodeficiency virus and IgA nephropathy
Authors: COHEN Arthur H.
Published: November 2010

Summary: IgA nephropathy (IgAN) in human immunodeficiency virus (HIV)‐infected patients has been described with increasing frequency. In contrast to HIV‐associated nephropathy, with collapsing variant of focal and segmental glomerulosclerosis and prominent tubular cell changes, a disorder which is more common in black persons, IgAN is a disease mainly of white patients. Most are asymptomatic carriers of HIV although few have acquired immunodeficiency syndrome (AIDS) or ARC at the time the renal disorder is discovered. The clinical manifestations are generally of haematuria, sometimes with proteinuria. In some patients, the finding of IgA reactive with anti‐HIV IgG or IgM in circulating immune complexes and in glomerular eluates strongly suggests this glomerulopathy to be an HIV‐associated immune complex disorder. Because of the demographic factors, IgAN may evolve to be an important renal lesion in HIV infection.
Treatment options in IgA nephropathy
Authors: JULIAN Bruce A. , BAKE A Warmold L van den WALL
Published: November 2010

Summary: IgA nephropathy (Berger's disease), the most common primary glomerulonephritis worldwide, leads to end‐stage renal failure in 20–40% of patients after 20 years of clinical disease. No consensus has emerged about treatment to slow or prevent the loss of renal function, and in large part this has been due to a critical lack of understanding of the pathogenetic mechanisms. Several approaches that reduce glomerular scarring and inflammation in other renal diseases, including fish oil supplements, anti‐inflammatory agents and angiotensin‐converting enzyme inhibitors, have been used, with variable results. For patients reaching end‐stage, transplantation has shown excellent long‐term outcomes.
Immunotherapy in IgA nephropathy
Authors: TOMINO Yasuhiko
Published: November 2010

Summary: The purpose of this presentation was to review the recent results of immunotherapy (i.e. corticosteroids, cyclosporine A and mizoribine), in patients with IgA nephropathy. We summarized the effects of corticosteroid therapy in patients with advanced stage of IgA nephropathy in our division. These patients were divided into steroid or non‐steroid (anti‐platelet and/or anti‐coagulation drug) therapy group. The clinical findings, 6 years after renal biopsy, were observed in this study. Mean levels of urinary protein excretion in the steroid therapy group (11 patients; 3.42 g/day) were higher than those in the non‐steroid therapy group (nine patients; 1.64 g/day) at the time of renal biopsy. The mean levels of creatinine clearance (CCr) in the steroid or non‐steroid therapy group were 61.2 and 78.6 mL/min, respectively. Efficacy of steroid or non‐steroid therapy was similar in patients with the advanced stage of IgA nephropathy, and it appeared that the steroid therapy was not effective for patients in the advanced stage of this disease. Cyclosporine A is a fungal peptide with immunoregulatory properties inhibiting activation of both T and B cells. Recently, a new immunosuppressive agent, mizoribine has been developed in Japan. Mizoribine has a suppressive effect on antibody formation via the direct inhibition of B cell function. Koshikawa et al. reported the effect of this drug in 158 patients with steroid‐resistant nephrotic syndrome in multi‐center studies in Japan. Mizoribine was administered orally at 150 mg/day for 24 weeks. Efficacy of treatment with mizoribine was marked compared with that with placebo in patients with IgA nephropathy and membranous nephropathy. At present, the authors are determining the clinicopathological effects of mizoribine in ddY mice, a spontaneous animal model of IgA nephropathy.
Getting started in CBPR: lessons in building community partnerships for new researchers
Authors: D’Alonzo Karen Therese
Published: November 2010

D’ALONZO KT. Nursing Inquiry 2010; 17: 282–288 Getting started in CBPR: lessons in building community partnerships for new researchers

There is a growing interest in community‐based participatory research (CBPR) methods to address issues of health disparities. Although the success of CBPR is dependent upon the formation of community‐researcher partnerships, new researchers as well as seasoned investigators who are transitioning to CBPR often lack the skills needed to develop and maintain these partnerships. The purpose of the article is to discuss the competencies needed by new researchers to form successful CBPR partnerships. The author presents a series of strategic steps that are useful in establishing academic–community partnerships and in initiating, maintaining and sustaining CBPR projects. These steps include suggestions regarding community engagement, selection of community advisory board members, outreach, the community’s role in problem identification, selection of research methodologies, considerations related to the community setting, need for flexibility and patience, ‘insider vs. outsider’ conflicts, commitment and training issues, timing concerns for tenure‐track faculty and the process of community empowerment. Community‐based participatory research is both rewarding and time consuming, for both the researcher and members of the community. Given its promise to address health disparities, it is imperative that researchers acquire the skills needed to develop and cultivate durable community‐researcher partnerships.
Managerial Legacies, Entrenchment, and Strategic Inertia
Authors: CASAMATTA CATHERINE , GUEMBEL ALEXANDER
Published: November 2010

This paper argues that the legacy potential of a firm's strategy is an important determinant of CEO compensation, turnover, and strategy change. A legacy makes CEO replacement expensive, because firm performance can only partially be attributed to a newly employed manager. Boards may therefore optimally allow an incumbent to be entrenched. Moreover, when a firm changes strategy it is optimal to change the CEO, because the incumbent has a vested interest in seeing the new strategy fail. Even though CEOs have no specific skills in our model, legacy issues can explain the empirical association between CEO and strategy change.
Antitrust economic analysis in food marketing channels: a global perspective
Authors: Cotterill Ronald W.
Published: November 2010

Antitrust enforcement concerning monopolies, mergers, and cartels is converging across all market‐oriented economies in the world. This convergence is based upon neoclassical economic analysis of industrial organization. The role of empirical economic analysis, however, has not converged as rapidly as the conceptual model because different countries have different enforcement institutions and strategies. This article explains how antitrust enforcement has evolved over time from public agencies to a market for enforcement that admits private parties. Private party law suits, and especially class action law suits on behalf of groups such as farmers and consumers, is a mechanism for redressing the often superior legal and economic resources that defendant corporations have and public agencies do not have. Enforcement and the role of empirical analysis are compared in the United States and other countries. Examples of enforcement from different countries illustrate the strengths and weaknesses of different approaches. Finally, some insights explain how economists function in enforcement and the attributes required for success.
The integration of energy and agricultural markets
Authors: Tyner Wallace E.
Published: November 2010

This article addresses the evolving links between energy and agricultural markets. Prior to 2005, there was little correlation between energy and agricultural commodity prices. In 2006–2008, with the ethanol boom in the United States, there emerged a strong link between crude oil, gasoline, and corn prices. There was little link between ethanol and corn. However, in late 2008 and 2009, the markets changed as ethanol production came under severe economic pressure and 2 billion out of 12 billion gallons of capacity shut down. During this period ethanol became priced more on corn, as the breakeven corn price helped drive the ethanol market. This article explores the drivers in these markets as well as other major issues facing the corn ethanol industry in the United States such as the blend wall. The article concludes with a review of prospects of a future cellulosic biofuels industry.
Bone mineral density in young males with ankylosing spondylitis
Authors: VASDEV Vivek , BHAKUNI Darshan , GARG Mahendra K. , NARAYANAN Krishanan , JAIN Rahul , CHADHA Davinder
Published: November 2010

Objective:  To assess bone mineral density (BMD) abnormalities in young Indian males with ankylosing spondylitis (AS) and factors influencing this.

Methods:  Eighty AS male subjects were compared with 160 age/sex matched controls for BMD of lumbar spine and proximal femur. AS subjects were evaluated and followed up every 3 months for disease activity. BMD was estimated at spine and proximal femur using the dual‐energy X‐ray absorptiometry (DXA) technique.

Results:  All subjects were males with mean age of 32.9 ± 8.3 years and mean duration of disease was 8.1 ± 5.8 years. AS subjects had significantly lower BMD at the spine and femur as compared with controls (both P < 0.001). Using WHO standards, osteoporosis (OP) in spine and femur neck was seen in 28.75% (controls: 1.84%, P < 0.001) and 11.54% (controls: 1.23%, P < 0.001), respectively. No statistically significant difference in prevalence of OP was seen with disease duration, C‐reactive protein levels and disease activity indices (all P > 0.05). Syndesmophytes were seen in 22.5% (n = 18) of AS subjects. There was no significant difference between BMD values at spine in AS subjects with or without syndesmophytes (0.91 + 0.16 g/cm2vs. 0.90 + 0.14 g/cm2, P = 0.79).

Conclusion:  OP is a significant complication in AS even in young males with early disease, and more prevalent in the spine compared to femur. In our study, BMD was not influenced by disease activity indices, inflammatory markers or total disease duration. Spinal BMD is the most sensitive site for defining OP in AS.
Contrasting Orientations: STSE for Social Reconstruction or Social Reproduction?
Authors: Barrett Sarah Elizabeth , Pedretti Erminia
Published: November 2010

Over the last 20 years, science‐technology‐society‐environment education (STSE) education has been advocated as a way to advance scientific literacy. However, STSE education represents a broad range of ideologies and orientations. The purpose of this study was to compare and contrast two different science curricula through a case study approach. This study followed three classroom teachers from Ontario who decided to write a locally developed STSE course to replace the one that the government had discontinued. Through an analysis of the current government mandated STSE curricula and the proposed STSE curriculum, two distinct orientations emerged: social reconstruction and social reproduction. The analysis work suggests that these two orientations have fundamental philosophical differences and are irreconcilable. The paper concludes with a discussion about the implications for science educators.
Direct Method to Maximize Net Power Output of Rankine Cycle in Low-Grade Thermal Energy Conversion
Authors: Sun Faming , Ikegami Yasuyuki
Published: November 2010

Using ammonia as working fluid, enthalpy equations corresponding to every point in Rankine cycle for low-grade thermal energy conversion (LTEC) are presented by employing curve-fitting method. Analytical equations of Rankine cycle analysis are thus set up. In terms of temperatures of the evaporator and condenser, the equation related to Rankine cycle net power output is then achieved. Furthermore, by using theoretical optimization method, the results of the maximum net power output of a Rankine cycle in LTEC are also reported. This study extends the recent flurry of publications about Rankine cycle power optimization in LTEC, which modified the ideal Rankine cycle to a Carnot cycle by using an average entropic temperature to achieve the theoretical formulas. The proposed method can better reflect the performance of Rankine cycle in LTEC since the current work is mainly based on the direct simulations of every enthalpy points in Rankine cycle. Moreover, the proposed method in this paper is equally applicable for other working mediums, such as water and R134a.
Safety and Pharmacokinetics of IDX184, a Liver-Targeted Nucleotide Polymerase Inhibitor of Hepatitis C Virus, in Healthy Subjects
Authors: Zhou Xiao-Jian , Pietropaolo Keith , Chen Jie , Khan Samina , Sullivan-Bólyai John , Mayers Douglas
Published: November 2010

IDX184 is a nucleotide prodrug designed to enhance formation in the liver of the active triphosphate of 2′-methylguanosine (2′-MeG), a potent and specific polymerase inhibitor of the hepatitis C virus (HCV). In the present study, single ascending oral doses of 5, 10, 25, 50, 75, and 100 mg IDX184 were administered sequentially to cohorts of 8 healthy subjects, randomized 6:2, active/placebo. Plasma and urine pharmacokinetic sampling was performed over a period of 120 h after dosing. Upon absorption, IDX184 rapidly disappeared from plasma, with a mean half-life (
t
1/2
) of approximately 1 h, while plasma concentrations of 2′-MeG gradually increased. Consistent with a liver-targeting approach, plasma exposure of IDX184 and 2′-MeG was low and was also dose related: the mean maximum concentrations ranged from 1.1 to 17 ng/ml for IDX184 and 1.7 to 19 ng/ml for 2′-MeG, and the respective mean total area under the curve ranged from 1.2 to 22.7 and 17.3 to 334 ng·h/ml. Mean 2′-MeG plasma concentrations 24 h after dosing were 0.6 to 3 ng/ml for the 25- to 100-mg doses. Mean 2′-MeG
t
1/2
values ranged from 18 to 43 h for doses of 25 mg and above. Mean cumulative urine excretion was 0.2% and 12 to 20% of administered doses for the unchanged IDX184 and 2′-MeG, respectively. IDX184 was safe and well tolerated; no serious adverse events (SAEs), dose-dependent adverse events (AEs), or dose-limiting toxicities were observed. The incidence of AEs and laboratory abnormalities was low and was similar among subjects receiving IDX184 or a placebo. All AEs were mild to moderate and resolved at the end of study. The favorable safety and pharmacokinetic profiles support further clinical evaluation of IDX184 in HCV-infected patients.
The return of individual research findings in paediatric genetic research
Authors: Hens Kristien , Nys Herman , Cassiman Jean-Jacques , Dierickx Kris
Published: November 2010

The combination of the issue of return of individual genetic results/incidental findings and paediatric biobanks is not much discussed in ethical literature. The traditional arguments pro and con return of such findings focus on principles such as respect for persons, autonomy and solidarity. Two dimensions have been distilled from the discussion on return of individual results in a genetic research context: the respect for a participant’s autonomy and the duty of the researcher. Concepts such as autonomy and solidarity do not fit easily in the discussion when paediatric biobanks are concerned. Although parents may be allowed to enrol children in minimal risk genetic research on stored tissue samples, they should not be given the option to opt out of receiving important health information. Also, children have a right to an open future: parents do not have the right to access any genetic data that a biobank holds on their children. In this respect, the guidelines on genetic testing of minors are applicable. With regard to the duty of the researcher the question of whether researchers have a more stringent duty to return important health information when their research subjects are children is more difficult to answer. A researcher’s primary duty is to perform useful research, a policy to return individual results must not hamper this task. The fact that vulnerable children are concerned, is an additional factor that should be considered when a policy of returning results is laid down for a specific collection or research project.
DYNAMIC OF SURFACE DIFFUSION PROCESS WITH PRESENCE OF ORDERING
Authors: RACHID NASSIF , NOUREDDINE MOHAMMED , KHALID SAADOUNI , YAHIA BOUGHALEB
Published: November 2010

A Monte Carlo simulation of the dynamics of diffusion process is presented in the framework of the lattice gas model. The considered lattice is of square geometry with lateral interaction energy between diffusive adsorbates. The paper is entirely devoted to first J FN and second J SN neighboring repulsive interactions with the ratio R=J SN /J FN in the [0, 1] interval. It is shown that repulsive second neighboring interaction allows emergency of new ordered phases at the coverages theta = 1/4 and 3/4 and induces anisotropy when R is greater than the magnitude 0.5. The present situation is similar to that of Sadiq and Binder, Surf. Sci.128, 350 (1985) except for the choice of transition probability. Particular attention is given to both the behavior of the tracer diffusion coefficient and to the static of the half-full lattice for which a complete phase diagram is derived from calculation of the apparent activation energy. Our dynamic calculations suggest that in the temperature range examined, the jump algorithm gives rise to acceptable results, even its criticable normalization factor.