bluuebunny/crossref_metadata_2025 huggingface dataset:
Daily selection of habitat in wild boar (Sus scrofa)
Authors: Spitz F. , Janeau G.
Published: March 2009

Spatial segregation of the sexes is observed in numerous species of ungulates, but are there other forms of segregation in species where spatial segregation is not present, such as in the wild boar? This study investigates the differences in habitat selection between two categories of individuals whose ecological requirements are supposedly divergent: subadult males, and females with dependent piglets. The proportion of the day spent in each category of habitat was used as a parameter representative of daily decisions. The overall results fit with the hypothesis that females with piglets avoid insecure habitats, and that both categories select habitats on the basis of food richness. In addition, it was found that the pattern of habitat selection depends on the total time spent moving slowly. A short duration of slow movement was observed only in males, but the time dedicated to efficient foraging (in rich habitats) was sufficient in all observations of all animals. Subadult males, therefore, do not differ from each other in foraging efficiency, but in the time spent on slow movement in secure habitats. Those spending more time active in secure habitats have the opportunity of performing more potentially beneficial activities such as social interactions and sexual contacts.
Evidence for food competition between mink (Mustela vison) and otter (Lutra lutra) on Scottish islands
Authors: Clode D. , Macdonald D. W.
Published: March 2009

Food competition between American mink and otters was measured by comparing the diets of sympatric mink and otter populations with those of allopatric populations. Niche breadth was narrower for otters than mink. Niche breadth was wider for both mink and otters on islands where they co‐existed in comparison to that of the allopatric populations. Niche overlap was lower in sympatric populations on islands with mammalian prey, however, niche overlap was not reduced on small islands without mammalian prey. Obtained data suggest that mink and otter compete for food resources and, when alternative prey sources are available, mink become more generalist predators to avoid competition with otters. However, when alternative prey sources are not available, both species become more generalist.
Temporal and spatial patterns in blue duikers Philatomba monticola and red duikers Cephalophus natalensis
Authors: Bowland A. E. , Perrin M. R.
Published: March 2009

Forest duikers spend a large proportion of the day engaged in sedentary behaviour. Both species were most active shortly after dawn and just before dusk and were relatively more active in habitats of higher quality. Though home‐range boundaries were dynamic (changing slightly during the year), core areas were permanent and remained fixed.

Blue duikers showed exclusive family home ranges with no overlap between neighbours, for this species home range and territory are synonymous. Red duiker home‐range overlap varied greatly (up to 100% in some cases) indicating the absence of territoriality. Core areas in the home range of both duiker species were usually associated with bedsites. In blue duiker, home ranges and core areas were fixed all year with no overlap between neighbours, while home ranges and core areas of red duikers overlapped extensively. Temporal separation in red duikers is suggested between some individuals and not others.
Diets and habitat preferences of three species of crocidurine shrews in arid southern Africa
Authors: Dickman C. R.
Published: March 2009

The diets and habitat preferences of three species of crocidurine shrews, Crocidura cyanea, C. fuscomurina, and C. hirta (Insectivora: Soricidae), were studied in arid areas of Namibia in March and April, 1992. Simultaneous sampling of the prey ingested and available along foraging trails showed that, although the shrews are generalist insectivores that take most types of prey from the range available, each species selected Araneida, Chilopoda, Isoptera, and insect larvae but avoided Formicidae. The preferred prey were mostly soft‐bodied with a relatively high ratio of body water to energy content, which may assist in maintenance of body water balance. The three species showed inconsistent preferences for rarer categories of prey such as Thysanura and Orthoptera, as well as for Coleoptera. Each species of shrew selected sites providing dense ground level vegetation and deep leaf litter, With the preference for cover being strongest in C. fuscomurina. Dense vegetation probably provides shelter from predators and high daytime temperatures; both C. fuscomurina and C. hirta used denser vegetation by day than by night. Each species foraged in leaf litter, perhaps increasing access to preferred types of prey. Preference for moist soil, especially in C. fuscomurina, probably also reflects increased access to preferred prey, although moist soil may also facilitate burrow construction. Because patterns of habitat and diet selection appear to be linked, future research on resource use in these shrews should be pursued most fruitfully in field experiments or captive laboratory trials.
Body condition affects implantation date in the European badger, Meles meles
Authors: Woodroffe Rosie
Published: March 2009

The European badger has been used for many years as a model for the study of delayed implantation. Extensive experimental work has shown that implantation, which occurs around the winter solstice, is triggered by photoperiod. This paper presents data on estimated implantation dates in a wild population of badgers, measured by ultrasound scanning. It shows that females' nutritional state prior to implantation also influences implantation date, with females in good condition implanting relatively early. Photoperiod is known to influence implantation on a timescale of months, but body condition acted on a timescale of days; thus while photoperiod may be used to set the time of breeding to correspond approximately with seasonal variation in good availability, females may use body condition to calibrate their reproduction in response to their own local conditions. Giving birth early in the year provides cubs with the maximum period of growth prior to the summer, when food availability is very low. Since females feed little during gestation and the early phases of lactation, females in good condition will be able to afford to implant earlier than those with smaller fat reserves.
Coefficients of digestibility and nutritional values of geophytes and tubers eaten by southern African mole‐rats (Rodentia: Bathyergidae)
Authors: Bennett N. C. , Jarvis J. U. M.
Published: March 2009

Subterranean rodents have high energy requirements when they are excavating their burrows. This study investigates the energy available to, and the efficiency with which it can be extracted by, four species of bathyergid mole‐rats fed natural diets ranging from the underground storage organs of geophytes to grass roots and leaves.

The digestibility coefficients of geophytes ranged from 53% for the fibrous tuber of the gemsbok cucumber to 95–7% for corms and bulbs. One species, Bathyergus suillus whose diet consists of over 80% grass, had a digestibility coefficient of 87% on an all grass diet.

All species had similar coefficients of digestibility of > 90% when fed on a uniform diet of sweet potato.

Bulbs and corms had a low fibre content (3–3–4%), high calorific value (15–16kJ/g) and high digestibility coefficients (95–7–96%) and on this diet the mole‐rats maintained their body mass. Food of lower digestibility tended to have a high fibre content (8–2–45%) and, with the exception of B. suillus, although the mole‐rats consumed a greater quantity of food, they lost mass. The sweet potato had a low fibre content (4–1 %) but was energetically very similar to bulbs and corms (15–5 kJ/g).

Geophytes which have low fibre contents are generally small (1–20 g), whereas geophytes with high fibre contents are much larger (30–2000 g) and often occur in more arid zones.
A new calceostomatine monogenean from the gills and buccal cavity of the catfish Arius graeffei from Moreton Bay, Queensland, Australia
Authors: Whittington I. D. , Kearn G. C.
Published: March 2009

Neocalceostomoides brisbanensis sp. nov. from the gill arches, gill rakers and buccal lining of the blue catfish, Arius graeffei, is described. It is distinguished from the type species Neocalceostomoides arii (Unnithan, 1964) by the presence of a convoluted vas deferens with a blind‐ending diverticulum; two lobes inside the vagina, each with ornamentation comprising rows of conical studs; two seminal receptacles and a post‐testicular connection between the gut caeca. There is a closer resemblance to Neocalceostomoides spinivaginalis Lim, 1995, which also has vaginal lobes with ornamentations, but in N. spinivaginalis these ornamentations are elongated and spine‐like and the penis tube and ‘gubernaculum’ are significantly longer. Neocalceostomoides brisbanensis was found on A. graeffei caught in Moreton Bay (sea water), Queensland, but not on catfish caught in the Brisbane River (fresh water). Some comments are made on the evolution and relationships of calceostomatines.
Functional forewing morphology and stridulation in crickets (Orthoptera, Grylloidea)
Authors: Desutter‐Grandcolas L.
Published: March 2009

Forewing morphology and infrastructure are analysed in three cricket species (Gryllus campestris, Oecanthus pellucens and Lerneca fuscipennis) and checked in 20 other genera. A strong dorsoventral asymmetry is demonstrated for the first time. The upper side of the tegmina is covered with hexagonal, more or less high crests forming reliefs. On the lower side, annulate, flat and thick veins exist. The distribution of the hexagons and that of the different vein types is uneven on the forewing surfaces. Their significance in forewing functional morphology is discussed in relation to stridulation and to current knowledge on cricket sound production mechanisms. Their extent and distribution, together with the number and strength of the veins and the surface of wing cells, could account for the vibrational characteristics of the cricket forewing and explain the diverse results obtained by several authors on Gryllus and Oecanthus.
Feeding behaviour in two scleroglossan lizards: Lacerta viridis (Lacertidae) and Zonosaurus laticaudatus (Cordylidae)
Authors: Urbani J.‐M. , Bels V. L.
Published: March 2009

This paper deals with a description of feeding phases in the scleroglossan lizard Zonosaurus laticaudatus by using high‐speed cinematography. Capture modes are compared with Lacerta viridis. Z. laticaudatus uses the tongue for capturing small prey while both species use jaw prehension for large prey. L. viridis always uses jaw prehension for small prey.
Observations on the timing of reproduction in the congeneric Comoro Island fruit bats, Pteropus livingstonii and P. seychellensis comorensis
Authors: Trewhella W. J. , Reason P. F. , Davies J. G. , Wray S.
Published: March 2009

Pteropus livingstonii (Gray 1866) is a highly endangered fruit bat of the Comoro Islands (Western Indian Ocean). Limited information on the bats' population biology is hampering conservation measures. During an expedition in 1992, observations were made on the timing of reproduction of P. livingstonii and the congeneric P. seychellensis comorensis (Nicoll, 1908): P. livingstonii breeds two months earlier than P. s. comorensis. These observations are discussed in relation to what is known about reproduction in Pteropus, and past observations on the Comorien Pteropus species.
Social distance in Bosnia‐Herzegovina and the North Caucasus region of Russia: Inter and intra‐ethnic attitudes and identities*
Authors: BAKKE KRISTIN M. , CAO XUN , O'LOUGHLIN JOHN , WARD MICHAEL D.
Published: March 2009

ABSTRACT. This article examines attitudinal differences and similarities among ethnic groups in conflict‐affected societies. Conventional wisdom tells us that societies that have experienced violent struggles in which individuals of different ethnic groups have (been) mobilized against each other are likely to become polarized along ethnic lines. Indeed, both policy‐makers and scholars often assume that such divisions are some of the main challenges that must be overcome to restore peace after war. We comparatively examine this conventional wisdom by mapping dimensions of social distance among 4,000 survey respondents in Bosnia‐Herzegovina and the North Caucasus region of Russia. The surveys were carried out in December 2005. Using multidimensional scaling methods, we do not find patterns of clear attitudinal cleavages among members of different ethnic groups in Bosnia‐Herzegovina. Nor do we find patterns of clear ethnic division in the North Caucasus, although our social distance matrices reveal a difference between Russians and ethnic minority groups.
Tolerant exclusion: expanding constricted narratives of wartime ethnic and civic nationalism1
Authors: NEUFELDT REINA C.
Published: March 2009

ABSTRACT.During war, the demarcation ‘enemy alien’– whether on ethnic or civic grounds – can lead to loss of political, social or economic rights. Yet not all minorities are excluded even though they pose problems for civic and ethnic national categories of belonging. This article explores the experiences of an ethno‐religious minority who posed an intriguing dilemma for ethnic and civic categorisation in North America during World War II. The Mennonite experience enables a close examination of the relationship between a minority ethnic (and religious) group and majority concepts of wartime civic and ethnic nationalism. The article supports arguments that both ethnic and civic nationalism produce markers for the exclusion of minority groups during wartime. It reveals that minority groups can unintentionally become part of majority ‘nationalisms’ as the content of what defines the national ideal shifts over time. The experiences also suggest that a minority group can help mobilise symbolic resources that participate in transforming what defines the national ideal.
Identity of non‐self‐evident nation: Czech national identity after the break‐up of Czechoslovakia and before accession to the European Union*
Authors: VLACHOVÁ KLÁRA , ŘEHÁKOVÁ BLANKA
Published: March 2009

ABSTRACT. In this study the authors analyse Czech national identity after the break‐up of Czechoslovakia and before accession to the European Union. National identity is understood here as a construct consisting of several elements, four of which the authors analyse: territorial identity (localism, regionalism, patriotism, and Europeanism), the image of the nation – the cultural nation (ethno‐nation) and the political nation (state‐nation), national pride (in general, and in cultural performance and in the performance of the state), and love for the nation – nationalism (or more precisely, chauvinism) and patriotism. To create a more complex picture of Czech national identity the authors compare it with national identities in eleven other European countries. To conclude, the authors analyse the attitudes of Czechs toward the European Union, and national identity is used as an important explanatory element of the support for EU governance.
Between nationalism and humanitarianism: the glocal discourse on refugees
Authors: HERZOG BEN
Published: March 2009

ABSTRACT. The public and researchers alike view global/humanitarian and local/national logics as based on different, and even contradictory, regimes of justification. In this paper, however, I argue that these logics are complementary in the case of refugees. By asking ‘who is a refugee?’ within the Israeli case study, I empirically ground the claim that nationalism and humanitarianism should be grasped as Glocal. Content analysis of the Israeli case reveals how the Israeli establishment ‘translates’ the universal notion of humanitarianism. Humanitarian discourse does not offer an answer to the refugee problem by invoking a universal identity, nor is it just a euphemism for particularistic interests. On the contrary, the humanitarian logic is in fact based on the national order, and does not attempt to replace it. The political meaning of the term ‘refugee’ is an endless transcription of the national logic, and thus cannot be cosmopolitan.
A case for Slovene nationalism: initial citizenship rules and the erasure*
Authors: ZORN JELKA
Published: March 2009

ABSTRACT. When Slovenia became a sovereign state in 1991, it had to define who its citizens were. Were all residents of Slovenia, regardless of their ethnic belonging, equal in this respect? This article provides an answer to this question by elucidating certain parts of the secession legislation – the initial designation of citizenry and one of its indirect outcomes, the erasure from the register of permanent residents. The ethnic/civic dichotomy will be applied in order to demonstrate opposing nationalist claims made by the ruling elite. In terms of specific processes, Slovene nationalism will be presented in three distinct phases: counter‐state nationalism (before the break‐up of Yugoslavia), state‐building nationalism (the initial designation of citizenry), and the nationalising state (after the secession; marked by the erasure and threats to revoke citizenship statuses of naturalised citizens).
AKAP10 (I646V) functional polymorphism predicts heart rate and heart rate variability in apparently healthy, middle‐aged European‐Americans
Authors: Neumann Serina A. , Tingley Whittemore G. , Conklin Bruce R. , Shrader Catherine J. , Peet Eloise , Muldoon Matthew F. , Jennings J. Richard , Ferrell Robert E. , Manuck Stephen B.
Published: March 2009

Previous evidence suggests that the dual‐specific A kinase‐anchoring protein 2 functional polymorphism (AKAP10 (A/G) I646V) influences heart rate (HR) and heart rate variability (HRV) in mice and humans (N=122) with cardiovascular disease. Here, we asked whether this AKAP10 variant predicts HR and HRV in a large sample of healthy humans. Resting HR and short‐term time and frequency domain measures of HRV (5 min during paced and unpaced respiration conditions) were assessed in a U.S. community sample (N=1,033) of generally healthy men and women (age 30–54) of European ancestry. Each person was genotyped for the AKAP10 variant. As with previous work, the AKAP10 Val allele predicted greater resting HR (Paced p<.01; Unpaced p<.03) and diminished HRV (Paced ps <.05) suggesting that this variant may modulate the sensitivity of cardiac pacemaker cells to autonomic inputs, possibly conferring risk for arrhythmias and sudden cardiac death.
Pupillometric measures of attentional allocation to target and mask processing on the backward masking task in schizophrenia
Authors: Granholm Eric , Fish Scott C. , Verney Steven P.
Published: March 2009

Allocation of attentional resources during early visual processing was investigated in schizophrenia. Pupillary responses were recorded during a backward masking task as an index of resource allocation in schizophrenia patients (n=51) and nonpsychiatric controls (n=51). Two time‐linked components of pupillary response waveforms appeared to differentially index resource allocation to targets versus masks. Two patient subgroups were identified: One with normal overall pupillary responses (resource allocation), but greater allocation on mask relative to target components, and another with abnormally small overall pupillary responses and similar allocation between target and mask components. Thus, misallocation of resources to masks contributed to masking deficits in one subgroup, whereas reduced resource allocation contributed to deficits in the other. The nature of resource‐related deficits can vary across schizophrenia subgroups.
Serial or parallel processing in dual tasks: What is more effortful?
Authors: Lehle Carola , Steinhauser Marco , Hübner Ronald
Published: March 2009

Recent studies indicate that dual tasks can be performed with a serial or parallel strategy and that the parallel strategy is preferred even if this implies performance costs. The present study investigates the hypothesis that parallel processing is favored because it requires less mental effort compared to serial processing. A serial or parallel processing strategy was induced in a sample of 28 healthy participants. As measures of mental effort, we used a rating as well as heart rate (HR) and electrodermal activity. Parallel processing again showed performance costs relative to serial, whereas serial processing was judged as more effortful. Also tonic HR and phasic HR deceleration were increased with a serial strategy. Thus the preference for a parallel strategy in dual tasks likely reflects a compromise between optimizing performance and minimizing the amount of mental effort. This aspect is neglected in current dual task accounts so far.
Cognitive processes facilitated by contextual cueing: Evidence from event‐related brain potentials
Authors: Schankin Andrea , Schubö Anna
Published: March 2009

Finding a target in repeated search displays is faster than finding the same target in novel ones (contextual cueing). It is assumed that the visual context (the arrangement of the distracting objects) is used to guide attention efficiently to the target location. Alternatively, other factors, e.g., facilitation in early visual processing or in response selection, may play a role as well. In a contextual cueing experiment, participant's electrophysiological brain activity was recorded. Participants identified the target faster and more accurately in repeatedly presented displays. In this condition, the N2pc, a component reflecting the allocation of visual‐spatial attention, was enhanced, indicating that attention was allocated more efficiently to those targets. However, also response‐related processes, reflected by the LRP, were facilitated, indicating that guidance of attention cannot account for the entire contextual cueing benefit.
Adult neural stem/progenitor cells reduce NMDA‐induced excitotoxicity via the novel neuroprotective peptide pentinin
Authors: Faijerson Jonas , Thorsell Annika , Strandberg Joakim , Hanse Eric , Sandberg Mats , Eriksson Peter S. , Tinsley Rogan B.
Published: March 2009

J. Neurochem. (2009) 109, 858–866.

Although the potential of adult neural stem cells to repair damage via cell replacement has been widely reported, the ability of endogenous stem cells to positively modulate damage is less well studied. We investigated whether medium conditioned by adult hippocampal stem/progenitor cells altered the extent of excitotoxic cell death in hippocampal slice cultures. Conditioned medium significantly reduced cell death following 24 h of exposure to 10 μM NMDA. Neuroprotection was greater in the dentate gyrus, a region neighboring the subgranular zone where stem/progenitor cells reside compared with pyramidal cells of the cornis ammonis. Using mass spectrometric analysis of the conditioned medium, we identified a pentameric peptide fragment that corresponded to residues 26–30 of the insulin B chain which we termed ‘pentinin’. The peptide is a putative breakdown product of insulin, a constituent of the culture medium, and may be produced by insulin‐degrading enzyme, an enzyme expressed by the stem/progenitor cells. In the presence of 100 pM of synthetic pentinin, the number of mature and immature neurons killed by NMDA‐induced toxicity was significantly reduced in the dentate gyrus. These data suggest that progenitors in the subgranular zone may convert exogenous insulin into a peptide capable of protecting neighboring neurons from excitotoxic injury.
Glutamate‐dependent transcriptional control in Bergmann glia: Sox10 as a repressor
Authors: Cruz‐Solis Irma , Zepeda Rossana C. , Ortiz Sharon , Aguilera José , López‐Bayghen Esther , Ortega Arturo
Published: March 2009

J. Neurochem. (2009) 109, 899–910.

Glutamate (Glu) is the major excitatory transmitter in the vertebrate brain. Ligand‐gated and G protein‐coupled Glu receptors present in glial cells are presumably involved in neuronal function. Activation of Bergmann glial Glu receptors triggers a membrane to nuclei signaling cascade that regulates gene expression at the transcriptional and translational levels. Sry‐related high‐mobility group box (Sox10), a member of the conserved high‐mobility group box transcription factor family is expressed in neural crest stem cells and in a subset of neural crest‐derived lineages that include glial, but not neuronal cells. To gain insight into the role of Sox10 in Bergmann glial cells, we explored its expression and regulation. We demonstrate herein that Sox10 is expressed in Bergmann glial cells and that its DNA binding activity, mRNA, and protein levels as well as its transcriptional behavior augments upon the activation of metabotropic Glu receptors. Increase in Sox10–DNA complexes and Sox10 mRNA and protein levels were found upon exposure to Glu. Over‐expression of Sox10 leads to transcriptional repression in reporter gene assays and in one of its target genes: the chick kainate binding protein gene. These findings add a new perspective into glial glutamatergic signaling and suggest the participation of Sox10 in cerebellar glutamatergic transactions.
The brain 5‐HT4receptor binding is down‐regulated in the Flinders Sensitive Line depression model and in response to paroxetine administration
Authors: Licht Cecilie L. , Marcussen Anders B. , Wegener Gregers , Overstreet David H. , Aznar Susana , Knudsen Gitte M.
Published: March 2009

The 5‐hydroxytryptamine (5‐HT4) receptor may be implicated in depression and is a new potential target for antidepressant treatment. We have investigated the brain 5‐HT4receptor [3H]SB207145 binding in the Flinders Sensitive Line rat depression model by quantitative receptor autoradiography, and related this to 5‐HT transporter (S)‐[N‐methyl‐3H]citalopram binding. We also determined the regulation of 5‐HT4receptor binding by 1, 14, and 21 days of paroxetine administration and subchronic 5‐HT depletion, and compared this with changes in 5‐HT2Areceptor [3H]MDL100907 binding. In the Flinders Sensitive Line, the 5‐HT4receptor and 5‐HT transporter binding were decreased in the dorsal and ventral hippocampus, and the changes in binding were directly correlated within the dorsal hippocampus. Chronic but not acute paroxetine administration caused a 16–47% down‐regulation of 5‐HT4receptor binding in all regions evaluated including the basal ganglia and hippocampus, while 5‐HT depletion increased the 5‐HT4receptor binding in the dorsal hippocampus, hypothalamus, and lateral globus pallidus. In comparison, the 5‐HT2Areceptor binding was decreased in the frontal and cingulate cortices after chronic paroxetine administration, and markedly reduced in several regions after 5‐HT depletion. Thus, the 5‐HT4receptor binding was decreased in the Flinders Sensitive Line depression model and in response to chronic paroxetine administration.
Ginsenoside Rg1 protects against 6‐OHDA‐induced neurotoxicity in neuroblastoma SK‐N‐SH cells via IGF‐I receptor and estrogen receptor pathways
Authors: Gao Quan‐Gui , Chen Wen‐Fang , Xie Jun‐Xia , Wong Man‐Sau
Published: March 2009

Our previous studies have demonstrated that ginsenoside Rg1 is a novel class of potent phytoestrogen and can mimic the action of estradiol in stimulation of MCF‐7 cell growth by the crosstalk between insulin‐like growth factor‐I receptor (IGF‐IR)‐dependent pathway and estrogen receptor (ER)‐dependent pathway. The present study was designed to investigate the neuroprotective effects of ginsenoside Rg1 against 6‐hydroxydopamine (6‐OHDA)‐induced neurotoxicity in human neuroblastoma SK‐N‐SH cells and the possible mechanisms. Pre‐treatment with ginsenoside Rg1 resulted in an enhancement of survival, and significant rescue occurred at the concentration of 0.01 μM on cell viability against 6‐OHDA‐induced neurotoxicity. These effects could be completely blocked by IGF‐IR antagonist JB‐1 or ER antagonist ICI 182780. 6‐OHDA arrested the cells at G0G1 phase and prevented S phase entry. Rg1 pre‐treatment could reverse the cytostatic effect of 6‐OHDA. Ginsenoside Rg1 also could attenuate 6‐OHDA‐induced decrease in mitochondrial membrane potential. These effects could also be completely blocked by JB‐1 or ICI 182780. Furthermore, 6‐OHDA‐induced up‐regulation of Bax and down‐regulation of Bcl‐2 mRNA and protein expression could be restored by Rg1 pre‐treatment. Rg1 pre‐treatment could reverse the down‐regulation of ERα protein expression induced by 6‐OHDA treatment. Cells transfected with the estrogen responsive element (ERE)‐luciferase reporter construct exhibited significantly increased ERE‐luciferase activity in the Rg1 presence, suggesting that the estrogenic effects of Rg1 were mediated through the endogenous ERs. These results suggest that ginsenoside Rg1 may attenuate 6‐OHDA‐induced apoptosis and its action might involve the activation of IGF‐IR signaling pathway and ER signaling pathway.
RE1 silencing transcription factor is involved in regulating neuron‐specific expression of α‐internexin and neurofilament genes
Authors: Ching Gee Y. , Liem Ronald K. H.
Published: March 2009

α‐Internexin and the neurofilament triplet proteins (NF‐L, NF‐M, and NF‐H) co‐assemble into intermediate filament networks in neurons. We have found that the RE1 silencing transcription factor (REST) plays a contributory role in the neuron‐specific expression of the α‐internexin, NF‐H and NF‐M genes. Chromatin immunoprecipitation and transient transfection experiments performed with catecholaminergic neuronal Cath a.‐differentiated (CAD) cells and non‐neuronal NIH3T3 cells demonstrated that REST repressed transcription of these genes in NIH3T3 cells by binding and recruiting mSin3A, CoREST, histone deacetylase (HDAC) 1 and MeCP2 to the RE1 sites in the intron‐1 of α‐internexin and the 5′ flanking regions of NF‐H and NF‐M. No repression effect of the RE1 sites was observed in CAD cells, which express these neuronal genes but not REST. Treatment of NIH3T3 cells with trichostatin A, a HDAC inhibitor, relieved the REST‐mediated repression and induced ectopic activation of α‐internexin, NF‐H and NF‐M. The trichostatin A treatment did not affect the levels of REST occupancy but caused coordinated changes in acetylation and methylation of histones around the RE1 sites of these genes in NIH3T3 cells consistent with a transition from transcriptional repression to transcriptional activation. Thus, REST regulates expression of these neuronal genes, partly by a HDAC‐dependent epigenetic mechanism.
Induction of tyrosine hydroxylase mRNA by nicotine in rat midbrain is inhibited by mifepristone
Authors: Radcliffe Pheona M. , Sterling Carol R. , Tank A. William
Published: March 2009

Repeated nicotine administration induces tyrosine hydroxylase (TH) mRNA in rat midbrain. In this study we investigate the mechanisms responsible for this response using two models of midbrain dopamine neurons, rat ventral midbrain slice explant cultures and mouse MN9D cells. In both models nicotine stimulates TH gene transcription rate in a dose‐dependent manner. However, this stimulation is short‐lived, lasting for 1 h, but less than 3 h, and is not sufficient to induce TH mRNA or TH protein. Nicotine elevates circulating glucocorticoids, which induce TH expression in some model systems. We tested the hypothesis that the effect of nicotine on midbrain TH mRNA is mediated by the glucocorticoid receptor. When rats are administered the glucocorticoid receptor antagonist mifepristone, the induction of TH mRNA by nicotine in both substantia nigra and ventral tegmentum is inhibited. Furthermore, the glucocorticoid receptor agonist dexamethasone stimulates TH gene transcription for sustained periods of time in both midbrain slices and MN9D cells, leading to induction of TH mRNA and TH protein. Our results are consistent with the hypothesis that nicotine induces TH mRNA in midbrain by elevating glucocorticoids, which then act on glucocorticoid receptors in dopamine neurons leading to transcriptional activation of the TH gene.
Landscape composition influences patterns of native and exotic lady beetle abundance
Authors: Gardiner M. M. , Landis D. A. , Gratton C. , Schmidt N. , O’Neal M. , Mueller E. , Chacon J. , Heimpel G. E. , DiFonzo C. D.
Published: March 2009

Aim  Coccinellid beetles are important predators that contribute to pest suppression in agricultural landscapes. Since the introduction of the exotic coccinellids Coccinella septempunctata L. and Harmonia axyridis Pallas into the USA, several studies have reported a decline of native Coccinellidae in agroecosystems. We aimed to investigate the influence of landscape composition on native and exotic coccinellid abundance within soybean fields.

Location  Iowa, Michigan, Minnesota and Wisconsin.

Methods  As part of a 2‐year study (2005–06) on the biological control of the soybean aphid, Aphis glycines Matsumura, we examined coccinellid communities in 33 soybean fields using yellow sticky card traps. Landscape heterogeneity and composition were measured at multiple spatial scales ranging 1–3.5 km from focal soybean fields where coccinellid sampling took place.

Results  Exotic species made up 90% of the total coccinellid community in Michigan soybean fields followed by Wisconsin (84%), Minnesota (66%) and Iowa (57%). Harmonia axyridis was the dominant exotic coccinellid in all states comprising 45–62% of the total coccinellid community, followed by C. septempunctata (13–30%). Two additional exotic species, Hippodamia variegata (Goeze) and Propylea quatuordecimpunctata (L.) were also found in the region. Overall, the most abundant native coccinellid was Hippodamia convergens Guerin‐Meneville; however, its abundance varied across the region, comprising 0% (Michigan) to 28% (Iowa) of the total coccinellid community. Landscape structure significantly influenced the composition of coccinellid communities in soybean agroecosystems. We found that native coccinellids were most abundant in low‐diversity landscapes with an abundance of grassland habitat while exotic coccinellids were associated with the abundance of forested habitats.

Main conclusion  We propose that grassland dominated landscapes with low structural diversity and low amounts of forested habitat may be resistant to exotic coccinellid build‐up, particularly H. axyridis and therefore represent landscape‐scale refuges for native coccinellid biodiversity.
Biological weathering and the long‐term carbon cycle: integrating mycorrhizal evolution and function into the current paradigm
Authors: TAYLOR L. L. , LEAKE J. R. , QUIRK J. , HARDY K. , BANWART S. A. , BEERLING D. J.
Published: March 2009

The dramatic decline in atmospheric CO2 evidenced by proxy data during the Devonian (416.0–359.2 Ma) and the gradual decline from the Cretaceous (145.5–65.5 Ma) onwards have been linked to the spread of deeply rooted trees and the rise of angiosperms, respectively. But this paradigm overlooks the coevolution of roots with the major groups of symbiotic fungal partners that have dominated terrestrial ecosystems throughout Earth history. The colonization of land by plants was coincident with the rise of arbuscular mycorrhizal fungi (AMF), while the Cenozoic (c. 65.5–0 Ma) witnessed the rise of ectomycorrhizal fungi (EMF) that associate with both gymnosperm and angiosperm tree roots. Here, we critically review evidence for the influence of AMF and EMF on mineral weathering processes. We show that the key weathering processes underpinning the current paradigm and ascribed to plants are actually driven by the combined activities of roots and mycorrhizal fungi. Fuelled by substantial amounts of recent photosynthate transported from shoots to roots, these fungi form extensive mycelial networks which extend into soil actively foraging for nutrients by altering minerals through the acidification of the immediate root environment. EMF aggressively weather minerals through the additional mechanism of releasing low molecular weight organic chelators. Rates of biotic weathering might therefore be more usefully conceptualized as being fundamentally controlled by the biomass, surface area of contact, and capacity of roots and their mycorrhizal fungal partners to interact physically and chemically with minerals. All of these activities are ultimately controlled by rates of carbon‐energy supply from photosynthetic organisms. The weathering functions in leading carbon cycle models require experiments and field studies of evolutionary grades of plants with appropriate mycorrhizal associations. Representation of the coevolution of roots and fungi in geochemical carbon cycle models is required to further our understanding of the role of the biota in Earth's CO2 and climate history.
The Historiography of the English State during ‘the Long Eighteenth Century’: Part I – Decentralized Perspectives
Authors: Devereaux Simon
Published: March 2009

This article reviews the four most prominent themes in the historiography of the modern English state during the last six decades, with a particular focus on ‘the long eighteenth century’ (1660–1837). The first is the vision of an expansive and centralized administrative state in Victorian England most famously set forth in the work of the late Oliver MacDonagh. Second is the notion of the state as an information‐gathering entity that has recently been forcefully stated by Edward Higgs. Third is the vision of an unexpectedly powerful, substantially centralized ‘fiscal‐military’ state during the eighteenth century, powerfully evoked in the work of John Brewer. Finally, a brief overview is given of the prodigious historical literature that has arisen in recent years surrounding the notion of the state as abstract entity capable of commanding the loyalties of those people over whom it rules. The article concludes by suggesting how a more fully integrated vision of the English state in history might be achieved through a deeper, more dynamic interrelation of changing political‐administrative structures and shifting social‐cultural forces.
The Archaeology of Medieval Europe
Authors: Crabtree Pam
Published: March 2009

Modern medieval archaeology developed in the aftermath of World War II. It began as a hybrid discipline, since archaeologists working in the later Middle Ages were often trained in history and architectural history, while those working in the early medieval period were often trained as prehistorians. A major challenge for medieval archaeologists is the integration of material remains (artifacts and features) and historical evidence. Archaeology is not just a handmaiden to history; critical interpretation of both material remains and written texts can shed new light on the so‐called Dark Ages. After reviewing the development of modern medieval archaeology, this article examines a number of contemporary issues in the field including the study of urban development, medieval landscapes and settlement patterns, ethnic origins, and gender.
Tensions of Colonial Punishment: Perspectives on Recent Developments in the Study of Coercive Networks in Asia, Africa and the Caribbean
Authors: Sherman Taylor C.
Published: March 2009

The study of penal practices in colonised parts of Asia, Africa, Latin America, the Indian Ocean and the Caribbean has recently witnessed a significant shift. The first generation of research into the coercive measures of colonial states tended to focus rather narrowly on imprisonment. The second generation, which has emerged only in the last five years, has significantly widened their field of vision to incorporate much more than the prison. The most recent literature considers capital and corporal punishment, as well as the larger functioning of police and courts. It also explores in more depth the ways in which indigenous peoples experienced and interpreted their punishments. Finally, this new research is sensitive to the paradoxes and tensions of colonial punishment, which often frustrated its purposes. This article reflects upon these historiographical shifts, and argues that, in light of these developments, a new framework for the study of colonial punishment is now called for. It suggests that an approach which views colonial coercive techniques as part of imperial ‘coercive networks’ encapsulates this new thinking.
Changes in hepatic gene expression in response to hepatoprotective levels of zinc
Authors: Liu Jie , Zhou Zhan‐Xiang , Zhang Wei , Bell Matthew W. , Waalkes Michael P.
Published: March 2009

Background:Zinc (Zn) administration at non‐toxic doses protects against the hepatotoxicity produced by many agents, but the underlying mechanisms remain elusive.

Aim:To examine the basis of Zn‐induced generalised hepatoprotective effects.

Methods:Rats and mice were given Zn at known hepatoprotective levels (100 μmol ZnCl2/kg/day, s.c., for 4 days) and molecular responses were assessed.

Results:Zn treatment produced changes in 5% of the genes on custom‐designed mouse liver array and Rat Toxicology‐II array. Changes in gene expression were further confirmed and extended by real‐time reverse transcriptase‐polymerase chain reaction. Zn treatment dramatically increased the expression of the metallothionein (Mt), and modestly increased the expression of acute‐phase protein genes (ceruloplasmin, Stat3, egr1, Cxc chemokinesand heat‐shock proteins). For genes encoding for antioxidant enzymes, some were increased (Nrf2andNqo1), while others remained unaltered (Cu, Zn SODand glutathioneS‐transferases). Expressions of cytokine and pro‐inflammatory genes were not affected, while genes related to cell proliferation (cyclin D1) were modestly upregulated. Some metabolic enzyme genes, including cytochrome P450s and UDP‐glucuronosyltransferase, were modestly suppressed, perhaps to switch cellular metabolic energy to acute‐phase responses. Liver Zn content was increased between 1.6‐ and 2.1‐fold, while hepatic MT protein was increased between 50 and 200‐fold. Mice typically showed greater responses than rats.

Conclusion:Such gene expression changes, particularly the dramatic induction of MT and Nrf2 antioxidant pathway, occur in the absence of overt liver injury, and are probably important in the hepatoprotective effects of Zn against toxic insults.
Complexity of the 8 ka climate event in Sweden recorded by varved lake sediments
Authors: ZILLÉN LOVISA , SNOWBALL IAN
Published: March 2009

Mineral magnetic and carbon analyses of a continuous varved lake sediment sequence in west‐central Sweden (Lake Mötterudstjärnet) complement similar palaeoclimate proxies obtained from two varved lake sediment sequences in northern Sweden and one in central Finland. The varve chronology is supported by tephrochronology, palaeomagnetic secular variations and 14C AMS dating of terrestrial macrofossils. We apply a simple model in which the transport and deposition of catchment mineral matter reflect the amount of winter snow accumulation, spring snow‐melt and stream discharge. Our data show that winter snow accumulation was generally enhanced in Sweden between 8100 and 7750 cal. yr BP. If dating errors are taken into account, the 350‐year period of increased erosion is the geomorphic response to a multi‐centennial scale climatic cooling that occurred some time between 8500 and 7500 cal. yr BP. The most significant erosion event in central Sweden was centred at 8050 cal. yr BP. It lasted 150 years (between 8100 and 7950 cal. yr BP) and is equivalent to the most extreme Holocene climate anomaly in the northern hemisphere, known as the 8 ka or 8200 cal. yr BP climate event. Our high‐resolution paramagnetic susceptibility and ferrimagnetic grain‐size parameters suggest that snowpack accumulation increased most significantly in northern Sweden between 7900 and 7750 cal. yr BP. We suggest that this north–south difference was a response to the re‐establishment of moisture‐laden westerly air masses, as meridional Atlantic overturning circulation was re‐established at the beginning of the Holocene thermal maximum.
A longitudinal study of surgical outcome and its determinants following posterior cortex epilepsy surgery
Authors: Jehi Lara E. , O’Dwyer Rebecca , Najm Imad , Alexopoulos Andreas , Bingaman William
Published: March 2009

Purpose:  To investigate the longitudinal seizure outcome and identify potential prognostic indicators following posterior cortex epilepsy (PCE) surgery.

Methods:  We reviewed patients who underwent a parietal, occipital, or parietooccipital resections between 1994 and 2006, using survival analysis and multivariate regression with Cox proportional hazard modeling. A favorable outcome was defined as Engel Class I at last follow‐up.

Results:  Fifty‐seven patients were identified with a mean follow‐up of 3.3 years (range 1–12 years). The estimated chance of seizure freedom (SF) was 73.1% at 6 postoperative months, 68.5% at 1 year, 65.8% at between 2 and 5 years, and 54.8% at 6 years and beyond. Most recurrences (75%) occurred within the first 6 postoperative months. Parietal resections had a worse outcome than occipital or parietooccipital resections (52% SF vs. 89% and 93%, respectively, at 5 years). Independent predictors of recurrence included an epilepsy etiology other than tumor or dysplasia [risk ratio (RR) 2.29], limiting resection to a lesionectomy (RR 2.10), having ipsilateral temporal spiking on preoperative scalp electroencephalography (EEG) (RR 2.06), or any ipsilateral spiking on postoperative EEG (RR 2.70) (Log likelihood‐ratio test p < 0.0001). Only 40–50% of patients with a poor outcome predictor were SF at 5 postoperative years as opposed to about 80% otherwise. In surgical failures, recurrent seizure frequency was related directly to baseline seizure frequency and to the presence of ipsilateral spiking on postoperative EEG.

Discussion:  These data highlight favorable long‐term outcomes following PCE surgery. Limited surgical resection and diffuse baseline epileptogenicity may be important predictors of seizure recurrence.
The use of radiosurgery for the treatment of mesial temporal lobe epilepsy and long‐term results
Authors: Vojtěch Zdeněk , Vladyka Vilibald , Kalina Miroslav , Nešpor Evžen , Seltenreichová Kateřina , Šemnická Jitka , Liščák Roman
Published: March 2009

Purpose: To determine the efficacy of gamma knife radiosurgery in the treatment of mesial temporal lobe epilepsy due to mesial temporal sclerosis.

Methods: Between November 1995 and May 1999, 14 patients underwent radiosurgical entorhinoamygdalohippocampectomy with a marginal dose of 18, 20, or 25 Gy to the 50% isodose following a standard preoperative epilepsy evaluation.

Results: One patient was classified as Engel Class Ib, three were Engel Class IIc, one was Engel Class IIIa, and two were Engel Class IVb in a subgroup of seven patients who were unoperated 2 years prior to the last visit and at least 8 years after irradiation (average 116 months). The insufficient effect of irradiation led us to perform epilepsy surgery on another seven patients an average of 63.5 months after radiosurgery. The average follow‐up period was 43.5 months after the operation. Four patients are seizure‐free; one is Engel Class IIb and one is Engel Class IId. One patient cannot be classified due to the short period of follow‐up. The frequency of seizures tended to rise after irradiation in some patients. Collateral edema was observed in nine patients, which started earlier and was more frequent in those irradiated with higher doses. It had a marked expansive character in three cases and clinical signs of intracranial hypertension were present in three cases. We found partial upper lateral quadrant anopia as a permanent side effect in two patients. Repeated psychotic episodes (two patients) and status epilepticus (two patients) were also seen after treatment. No significant memory changes occurred in the group as a whole.

Discussion: Radiosurgery with 25, 20, or 18‐Gy marginal dose levels did not lead to seizure control in our patient series, although subsequent epilepsy surgery could stop seizures. Higher doses were associated with the risk of brain edema, intracranial hypertension, and a temporary increase in seizure frequency.