bluuebunny/crossref_metadata_2025 huggingface dataset:
Generative models of rich clubs in Hebbian neuronal networks and large-scale human brain networks
Authors: Vértes Petra E. , Alexander-Bloch Aaron , Bullmore Edward T.
Published: September 2014

Rich clubs arise when nodes that are ‘rich’ in connections also form an elite, densely connected ‘club’. In brain networks, rich clubs incur high physical connection costs but also appear to be especially valuable to brain function. However, little is known about the selection pressures that drive their formation. Here, we take two complementary approaches to this question: firstly we show, using generative modelling, that the emergence of rich clubs in large-scale human brain networks can be driven by an economic trade-off between connection costs and a second, competing topological term. Secondly we show, using simulated neural networks, that Hebbian learning rules also drive the emergence of rich clubs at the microscopic level, and that the prominence of these features increases with learning time. These results suggest that Hebbian learning may provide a neuronal mechanism for the selection of complex features such as rich clubs. The neural networks that we investigate are explicitly Hebbian, and we argue that the topological term in our model of large-scale brain connectivity may represent an analogous connection rule. This putative link between learning and rich clubs is also consistent with predictions that integrative aspects of brain network organization are especially important for adaptive behaviour.
Probing scale interaction in brain dynamics through synchronization
Authors: Barardi Alessandro , Malagarriga Daniel , Sancristobal Belén , Garcia-Ojalvo Jordi , Pons Antonio J.
Published: September 2014

The mammalian brain operates in multiple spatial scales simultaneously, ranging from the microscopic scale of single neurons through the mesoscopic scale of cortical columns, to the macroscopic scale of brain areas. These levels of description are associated with distinct temporal scales, ranging from milliseconds in the case of neurons to tens of seconds in the case of brain areas. Here, we examine theoretically how these spatial and temporal scales interact in the functioning brain, by considering the coupled behaviour of two mesoscopic neural masses (NMs) that communicate with each other through a microscopic neuronal network (NN). We use the synchronization between the two NM models as a tool to probe the interaction between the mesoscopic scales of those neural populations and the microscopic scale of the mediating NN. The two NM oscillators are taken to operate in a low-frequency regime with different peak frequencies (and distinct dynamical behaviour). The microscopic neuronal population, in turn, is described by a network of several thousand excitatory and inhibitory spiking neurons operating in a synchronous irregular regime, in which the individual neurons fire very sparsely but collectively give rise to a well-defined rhythm in the gamma range. Our results show that this NN, which operates at a fast temporal scale, is indeed sufficient to mediate coupling between the two mesoscopic oscillators, which evolve dynamically at a slower scale. We also establish how this synchronization depends on the topological properties of the microscopic NN, on its size and on its oscillation frequency.
Cribrihabitans neustonicus sp. nov., isolated from coastal surface seawater, and emended description of the genus Cribrihabitans Chen et al. 2014
Authors: Hameed Asif , Shahina Mariyam , Lin Shih-Yao , Lai Wei-An , Liu You-Cheng , Hsu Yi-Han , Young Chiu-Chung
Published: September 2014

A Gram-stain-negative, strictly aerobic, rod- or oval-shaped, motile, non-spore-forming bacterium, designated strain CC-AMHB-3T, was isolated from coastal surface seawater off Hualien, Taiwan. The novel strain showed high pairwise 16S rRNA gene sequence similarities to

Ruegeria mobilis

NBRC 101030T (96.5 %),

Ruegeria scottomollicae

LMG 24367T (96.4 %),

Phaeobacter aquaemixtae

SSK6-1T (96.2 %),

Phaeobacter daeponensis

TF-218T (96.2 %),

Cribrihabitans marinus

CZ-AM5T (96.1 %) and other species of the family

Rhodobacteraceae

(≤95.9 %). However, strain CC-AMHB-3T formed a distinct phyletic lineage associated with

C. marinus

CZ-AM5T during phylogenetic analyses. The polar lipid profile of strain CC-AMHB-3T included major amounts of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylcholine; moderate amounts of phosphatidylethanolamine, an unidentified aminolipid, an unidentified phospholipid and an unidentified lipid; and trace amounts of an unidentified lipid and an unidentified phospholipid, which was qualitatively almost in line with that of

C. marinus

CZ-AM5T but remarkably distinct as compared with the type species of the genera

Ruegeria

(

Ruegeria atlantica

JCM 21234T) and

Phaeobacter

(

Phaeobacter gallaeciensis

JCM 21319T). In line with the fatty acid profile of

C. marinus

CZ-AM5T, the major (>5 % of total) fatty acids of strain CC-AMHB-3T were C18 : 1ω7c and/or C18 : 1ω6c (summed feature 8), 11-methyl C18 : 1ω7c and C16 : 0. The DNA G+C content was 66.7 mol%. Ubiquinone-10 (Q-10) was the sole respiratory quinone. Thus, based on the results of the polyphasic study presented here, strain CC-AMHB-3T is considered to represent a novel species of the genus

Cribrihabitans

, for which the name Cribrihabitans neustonicus sp. nov. is proposed; the type strain is CC-AMHB-3T ( = JCM 19537T = BCRC 80695T). In addition, an emended description of the genus

Cribrihabitans

is also proposed.
Weissella uvarum sp. nov., isolated from wine grapes
Authors: Nisiotou Aspasia , Dourou Dimitra , Filippousi Maria-Evangelia , Banilas Georgios , Tassou Chrysoula
Published: September 2014

Two bacterial strains (B18BM42T and B18NM6) were recovered during a study of bacterial diversity on wine grapes (Vitis vinifera L.) from the Nemea region in Greece. Phylogenetic analysis based on 16S rRNA gene sequences placed the two strains within the genus

Weissella

, and found them to be most closely related to

Weissella minor

NRIC 1625T followed by

Weissella viridescens

NRIC 1536T (99.1 and 98.9 % sequence similarity, respectively). The level of DNA–DNA relatedness between strains B18NM42T and

W. minor

NRIC 1625T or

W. viridescens

NRIC 1536T was 31.9 and 35.0 %, respectively. The two novel strains could be genetically differentiated from their closest relatives by REA-PFGE (restriction enzyme analysis-pulse field gel electrophoresis), RAPD (randomly amplified polymorphic DNA) and rep-PC R analyses (repetitive sequence-based PCR). Physiological examination showed that the novel strains can be distinguished from phylogenetically related species by their ability to grow at 42 °C and by certain carbohydrate fermentations. Based on the evidence above, the affiliation of the two strains to a novel species with the proposed name Weissella uvarum sp. nov. is suggested. The type strain is B18NM42T ( = DSM 28060T = NCCB 100484T).
Paenibacillus guangzhouensis sp. nov., an Fe(III)- and humus-reducing bacterium from a forest soil
Authors: Li Jibing , Lu Qin , Liu Ting , Zhou Shungui , Yang Guiqin , Zhao Yong
Published: September 2014

A Gram-reaction-variable, rod-shaped, motile, facultatively aerobic and endospore-forming bacterium, designated strain GSS02T, was isolated from a forest soil. Strain GSS02T was capable of reducing humic substances and Fe(III) oxides. Strain GSS02T grew optimally at 35 °C, at pH 78 and in the presence of 1 % NaCl. The predominant menaquinone was MK-7. The major cellular fatty acids were anteiso-C15 : 0 and iso-C16 : 0 and the polar lipid profile contained mainly phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol, with moderate amounts of two unknown aminophospholipids and a minor amount of one unknown lipid. The DNA G+C content was 53.4 mol%. Comparative 16S rRNA gene sequence analysis showed that strain GSS02T was related most closely to

Paenibacillus terrigena

JCM 21741T (98.1 % similarity). Mean DNA–DNA relatedness between strain GSS02T and

P. terrigena

JCM 21741T was 58.8±0.5 %. The phylogenetic, chemotaxonomic and phenotypic results clearly demonstrated that strain GSS02T belongs to the genus

Paenibacillus

and represents a novel species, for which the name Paenibacillus guangzhouensis sp. nov. is proposed. The type strain is GSS02T ( = KCTC 33171T = CCTCC AB 2013236T).
MicroRNAs control the apoptotic threshold in primed pluripotent stem cells through regulation of BIM
Authors: Pernaute Barbara , Spruce Thomas , Smith Kimberley M. , Sánchez-Nieto Juan Miguel , Manzanares Miguel , Cobb Bradley , Rodríguez Tristan A.
Published: September 2014

Mammalian primed pluripotent stem cells have been shown to be highly susceptible to cell death stimuli due to their low apoptotic threshold, but how this threshold is regulated remains largely unknown. Here we identify microRNA (miRNA)-mediated regulation as a key mechanism controlling apoptosis in the post-implantation epiblast. Moreover, we found that three miRNA families, miR-20, miR-92, and miR-302, control the mitochondrial apoptotic machinery by fine-tuning the levels of expression of the proapoptotic protein BIM. These families therefore represent an essential buffer needed to maintain cell survival in stem cells that are primed for not only differentiation but also cell death.
Genetically Engineered Knock-In and Conditional Knock-In Mouse Models of Cancer
Authors: Rappaport Amy , Johnson Leisa
Published: September 2014

Classical transgenic models are useful for quickly gauging the impact of transgene overexpression, but they are limited by the absence of the innate, subtle regulatory elements encoded in introns and other untranslated regions. Moreover, the widespread, high-level expression of oncogenes often leads to tumors that lack the histopathological and acquired genetic features of human cancers. Targeted mutation of endogenous loci, or knock-in (KI) alleles, facilitates more accurate modeling of human tumors by allowing for the expression of mutant alleles under normal physiological regulation. Advanced strategies enable the stochastic activation of such alleles in somatic cells, such that genotypically wild-type cells surround individual mutant cells. More recent technologies, such as site-specific engineered nucleases, have also accelerated the design and implementation of KI strategies. Together, these tools aid in the development of advanced mouse models that better recapitulate the features of human disease.
Subcellular Fractionation of Rough Microsomes
Authors: Sabatini David D.
Published: September 2014

When eukaryotic cells are homogenized, the rough endoplasmic reticula are converted into small vesicles, called rough microsomes. Strategies for the isolation of rough microsomes are introduced here, as are methods for evaluating the purity and intactness of an isolated rough microsomal fraction.
Loss of heterosis and family‐dependent inbreeding depression in plant performance and resistance against multiple herbivores under drought stress
Authors: Prill Nadine , Bullock James M. , van Dam Nicole M. , Leimu Roosa
Published: September 2014

Inbreeding depression (ID), outbreeding depression (OD) and heterosis can occur concurrently in plant populations. ID often increases under environmental stress, but the combined effects of inbreeding, outbreeding between populations and environmental stress, such as drought, on plant performance and herbivore resistance remain unclear.

In order to determine environment‐dependent and family‐dependent ID, OD and heterosis, we conducted a common garden experiment with plants from five populations of Brassica nigra. Inbred, within‐population outbred and between‐population outbred plant families were exposed to drought or ambient water levels. We recorded the abundance and damage caused by specialist herbivores from contrasting feeding guilds, that is the phloem‐feeding Brevicoryne brassicae, the leaf‐chewing Psylliodes chrysocephalus and the stem‐boring Ceutorhynchus quadridens larvae.

Drought stress had negative effects on growth, herbivore resistance and resistance against B. brassicae and positive effects on investments in reproductive output and plant secondary metabolites (sinigrin). We found drought stress‐induced loss of heterosis for plant height and investment in reproductive output. Between‐population outbred plants were more sensitive to drought stress in terms of above‐ground biomass compared to within‐population outbred plants.

Drought and inbreeding synergistically negatively influenced traits related to growth and reproductive output (environment‐dependent inbreeding depression, EDID). There was high variation among families within populations in the degree of ID and EDID. Genetic variation in EDID could buffer the negative effects of genetic stress associated with habitat fragmentation and concurrent environmental stress. In order to capture fully the effects of both inbreeding and between‐population outbreeding under stress, the different spatial scales of the effects of inbreeding and between‐population outbreeding should be taken into account.

Synthesis. Our results indicate that drought stress influences not only inbreeding depression (ID), but also heterosis. These findings shed new light on the combined effects of anthropogenic environmental change and the genetic consequences of habitat fragmentation on plants and their interactions with other organisms. Conservation programmes aiming to restore genetically degraded populations with the translocation of individuals between populations should consider environmental stress as a risk factor.
Pronoun comprehension in individuals with Down syndrome: the role of age
Authors: Sanoudaki Eirini , Varlokosta Spyridoula
Published: September 2014

Background

A number of studies have suggested that language in individuals with Down syndrome (DS) may not be simply delayed compared with language in typically developing (TD) children, but deviant. The deviance has been detected in the comprehension of pronouns, and it has triggered proposals for the existence of a specific syntactic deficit in individuals with DS. However, the developmental path of pronoun comprehension in individuals with DS is unknown as there are no studies examining individuals of different ages.

Aims

To perform a pilot study examining pronoun comprehension in adolescents and adults with DS in comparison with TD children. Research questions include: Are some pronoun types more difficult than others for each of the two groups (DS and TD)? Is there a difference in performance between the two groups? Does performance correlate with chronological age in the DS group?

Methods & Procedures

Using a manual picture selection task, we examined the comprehension of different types of pronouns in 14 Greek‐speaking individuals with DS, ranging from 10 to 34 years of age. We also tested a control group of TD children as well as a typical adult group. The TD and DS groups were recruited and tested in pre‐schools and schools/centres for individuals with learning disabilities, respectively. Within‐ and between‐group comparisons were performed for all conditions. For the DS group, correlations between chronological age and performance in each condition were also explored.

Outcomes & Results

Results reveal a significant positive correlation of age with performance in the DS group, but only in structures that also presented difficulties to TD children. Structures that presented difficulties only to individuals with DS do not appear to be less problematic for older participants.

Conclusions & Implications

These findings provide support to the deviance hypothesis by suggesting that the syntactic deficit in the comprehension of pronouns in individuals with DS is present in individuals of a wide age range. At the same time, the results, if corroborated by large‐scale studies, suggest that some aspects of grammatical development in individuals with DS may continue even after adolescence and well into adulthood. We argue that these findings can contribute towards more targeted intervention practices by increasing our knowledge of the behavioural phenotype of DS.
Identification of active denitrifiers in full‐scale nutrient removal wastewater treatment systems
Authors: McIlroy Simon Jon , Starnawska Anna , Starnawski Piotr , Saunders Aaron Marc , Nierychlo Marta , Nielsen Per Halkjær , Nielsen Jeppe Lund
Published: September 2014

Denitrification is essential to the removal of nitrogen from wastewater during treatment, yet an understanding of the diversity of the active denitrifying bacteria responsible in full‐scale wastewater treatment plants (WWTPs) is lacking. In this study, stable‐isotope probing (SIP) was applied in combination with microautoradiography (MAR)‐fluorescence in situ hybridization (FISH) to identify previously unrecognized active denitrifying phylotypes in a full‐scale WWTP with biological N and P removal. Acknowledging that different denitrifiers will have specific carbon source preferences, a fully 13C‐labelled complex substrate was used for SIP incubations, under nitrite‐reducing conditions, in order to maximize the capture of the potentially metabolically diverse denitrifiers likely present. Members of the Rhodoferax, Dechloromonas, Sulfuritalea, Haliangium and Thermomonas were represented in the 16S rRNA gene clone libraries from DNA enriched in 13C, with FISH probes optimized here for their in situ characterization. FISH and MAR confirmed that they were all active denitrifiers in the community. The combined approach of SIP and MAR‐FISH represents an excellent approach for identifying and characterizing an un‐described diversity of active denitrifiers in full‐scale systems.
Stability of Iron–Quercetin Complexes in Synthetic Wine under In Vitro Digestion Conditions
Authors: Escudero Leticia B. , Fusari Cecilia M. , Altamirano Jorgelina C. , Camargo Alejandra B. , Wuilloud Rodolfo G.
Published: September 2014

Wine is a dietary source of polyphenolic compounds with reported health benefits when moderately consumed. Several of these compounds can associate with metals forming complexes. Therefore, this work was conducted to reach a better understanding of the nature and chemical stability of wine‐derived Fe3+–quercetin complexes in a digestion model. The stability of the complexes in a synthetic (simulated) wine was studied before and after in vitro gastric and intestinal digestions by high‐performance liquid chromatography (HPLC) with UV‐Vis detection. Metal determination was performed by atomic absorption spectrometry (ETAAS) to evaluate possible dissociation of complexes. During HPLC analysis all peaks eluted from the chromatographic column were collected, acidified, and analyzed by ETAAS. The results showed that complexes remain substantially stable after gastric digestion conditions, with recoveries of 84% to 90%. Although metal complexes were partially degraded during intestinal digestion, 41% to 45% of the Fe3+–quercetin complexes was recovered.
Color and Volatile Analysis of Peanuts Roasted Using Oven and Microwave Technologies
Authors: Smith Alicia L. , Barringer Sheryl A.
Published: September 2014

Roasted peanut color and volatiles were evaluated for different time and temperature combinations of roasting. Raw peanuts were oven roasted at 135 to 204 °C, microwave roasted for 1 to 3 min, or combination roasted by microwave and oven roasting for various times and temperatures. Volatiles were measured using selected ion flow tube mass spectrometry. L* values were used to categorize peanuts as under‐roasted, ideally roasted, and over‐roasted. The total roasting time in order to achieve ideal color was not shortened by most of the combination treatments compared to their oven roasted equivalents. Oven before microwave roasting compared to the reverse was found to significantly increase the L* value. Peanuts with the same color had different volatile levels. Hexanal concentrations decreased then increased with roasting. Pyrazine levels increased as roasting time increased, although oven at 177 °C treatments had the highest and microwave treatments had the lowest levels. Volatile levels generally increased as roasting time or temperature increased. Oven 177 °C for 15 min generally had the highest level of volatiles among the roasting treatments tested. Soft independent modeling of class analogies based on volatile levels showed that raw peanuts were the most different, commercial samples were the most similar to each other, and oven, microwave, and combination roasting were all similar in volatile profile.
Assessing trap and lure effectiveness for the monitoring of Sirex noctilio
Authors: Hurley Brett P. , Garnas Jeff , Cooperband Miriam F.
Published: September 2014

Lure‐baited traps are an important tool for monitoring the spread and establishment of the Sirex woodwasp Sirex noctilio. The utility of these traps, however, is limited in areas with low wasp populations as a result of the reliance on a plant volatile (kairomone) lure in the absence of an identified pheromone. Knowledge of the optimal trap type and deployment strategy is also lacking.

We tested the effectiveness of a putative pheromone in baited traps, by means of a series of field trials in South Africa, over a 3‐year period. We also examined the influence of lure type, trap type and trap height on capture success.

The pheromone was found to be ineffective as an attractant under South African field conditions for both male and female wasps. Lure type, trap type and trap height were found to have little to no effect on female wasp catch. Given the moderately strong responses to the blend under wind tunnel and laboratory conditions, we suggest possible aspects of the biology and life history of S. noctilio that may influence lure effectiveness.

The traditional black intercept panel traps with kairomone lure remains the best trap for S. noctilio, at least where populations are high.
Structure and composition of snake assemblages across three types of plantation in south‐eastern Nigeria
Authors: Akani Godfrey C. , Petrozzi Fabio , Eniang Edem A. , Luiselli Luca
Published: September 2014

Assemblage structure, diversity measures and diversity/dominance patterns of snakes were studied between 1996 and 2013 in three types of plantation in the Niger River delta of southern Nigeria. The investigated plantation types were pineapple, banana/plantain, and cassava/yam. Over 74% of the census species (n = 27) were found in all three plantation types, with, overall, just two singletons (Bitis nasicornis, Lamprophis olivaceus) being observed. Despite an overall similarity in the taxonomic species composition, a principal component analysis placed the three plantation types in distinct zones of the multivariate space. Diversity/dominance diagrams for the three plantation types showed that banana/plantain and cassava/yam were nearly identical in terms of evenness profile, whereas the pineapple plantation had a higher evenness.
Fair Trade Awareness and Engagement: A Coffee Farmer's Perspective
Authors: Fergus Andrew H. T. , Gray Adina
Published: September 2014

As one of the world's most traded commodities, coffee has been criticized for its contribution to environmental degradation, social injustice, and economic disparities between the producing regions of the Global South and consuming countries of the Global North. However, the Fair Trade concept is promising to change this through the establishment of a trading system where producers, importers, and processors form a more direct network characterized by an established set of ethical principles and practices deemed as “fair.” While the transformational benefits of Fair Trade at the producer level have been examined in several impact studies, the farmers' low awareness and understanding of Fair Trade concepts, principles, markets, and customers represent an issue of concern. Among the many benefits associated with increased Fair Trade awareness is greater participation in Fair Trade governance bodies and the long‐term viability of the market itself.

This research looks at Fair Trade from the perspective of farmers and their cooperative and uses the case of Cooperativa Agraria Cafetalera Pangoa, Peru, to examine how Fair Trade awareness (defined as knowledge of different areas of Fair Trade) is understood at the producer level. We then develop a three‐level Fair Trade awareness Model that illustrates both the existing and desired levels of understanding with regard to Fair Trade awareness.
The Gatekeeping Function of Trust in Cross‐sector Social Partnerships
Authors: Venn Ronald , Berg Nicola
Published: September 2014

Hunger and deprivation, lack of education, sanitation, and health care are only a few pressing issues related to poverty in developing countries. Addressing such complex social issues requires pooling complementary resources of the civil, public, and private sector. Over the last decade, stakeholders tried to cocreate innovative solutions in cross‐sector social partnerships (CSSPs) at the base of the economic pyramid (BoP), but collaboration proved to be very challenging. Practitioners become increasingly frustrated with operational differences, intransparency, and mismatched goals in partnerships. This study unravels the black box of collaboration and delivers empirical insights on trust and power inCSSPsbased on social exchange theory. Structural equation modeling (SEM) enables us explore relationships beyond case‐based insights. Our rigorous empirical analysis covers 207 interorganizational relationships and outlines a crucial gatekeeping function of trust inCSSPs. Findings provide strong empirical support for conceptual works calling for an “integrative orientation” inCSSPs. Furthermore, we pinpoint the role of intermediates and draw implications for future research.
When and How to Pursue Corporate Social Responsibility with Core Competencies
Authors: Webb Michael A.
Published: September 2014

We first establish that the pursuit of corporate social responsibility (CSR) can enhance the society's welfare when both market and government imperfections occur, and demonstrate this is likely in most locales across the world. Second, we show that CSR initiatives are most likely successful and sustainable when a firm accurately identifies the benefits and costs of potential CSR initiatives and implements them consistent with its core competencies. We provide three reasons for a firm to focus CSR initiatives on core competencies: to reap economies of scale and scope in building company‐wide knowledge and skills; to promote worker productivity that is integral to the firm; and to exploit the fixed costs associated with managing workers. Each reason provides a distinct way to minimize the costs and increase the gains from pursuing CSR initiatives and provides implications for implementing CSR initiatives.
Refining the pattern and style of Cordilleran Ice Sheet retreat: palaeogeography, evolution and implications of lateglacial ice‐dammed lake systems on the southern Fraser Plateau, British Columbia, Canada
Authors: Perkins Andrew J. , Brennand Tracy A.
Published: September 2014

Decay of the last Cordilleran Ice Sheet (CIS) near its geographical centre has been conceptualized as being dominated by passive downwasting (stagnation), in part because of the lack of large recessional moraines. Yet, multiple lines of evidence, including reconstructions of glacio‐isostatic rebound from palaeoglacial lake shoreline deformation suggest a sloping ice surface and a more systematic pattern of ice‐margin retreat. Here we reconstructed ice‐marginal lake evolution across the subdued topography of the southern Fraser Plateau in order to elucidate the pattern and style of lateglacial CIS decay. Lake stage extent was reconstructed using primary and secondary palaeo‐water‐plane indicators: deltas, spillways, ice‐marginal channels, subaqueous fans and lake‐bottom sediments identified from aerial photograph and digital elevation model interpretation combined with field observations of geomorphology and sedimentology, and ground‐penetrating radar surveys. Ice‐contact indicators, such as ice‐marginal channels, and grounding‐line moraines were used to refine and constrain ice‐margin positions. The results show that ice‐dammed lakes were extensive (average 27 km2; max. 116 km2) and relatively shallow (average 18 m). Within basins successive lake stages appear to have evolved by expansion, decanting or drainage (glacial lake outburst flood, outburst flood or lake maintenance) from southeast to northwest, implicating a systematic northwestward retreating ice margin (rather than chaotic stagnation) back toward the Coast Mountains, similar in style and pattern to that proposed for the Fennoscandian Ice Sheet. This pattern is confirmed by cross‐cutting drainage networks between lake basins and is in agreement with numerical models of North American ice‐sheet retreat and recent hypotheses on lateglacial CIS reorganization during decay. Reconstructed lake systems are dynamic and transitory and probably had significant effects on the dynamics of ice‐marginal retreat, the importance of which is currently being recognized in the modern context of the Greenland Ice Sheet, where >35% of meltwater streams from land‐terminating portions of the ice sheet end in ice‐contact lakes.
Oligoclonal bands in patients with multiple myeloma: Its emergence per se could not be translated to improved survival
Authors: Fujisawa Manabu , Seike Keisuke , Fukumoto Kouta , Suehara Yasuhito , Fukaya Masafumi , Sugihara Hiroki , Takeuchi Masami , Matsue Kosei
Published: September 2014

The emergence of oligoclonal bands (OB) has been reported in patients with multiple myeloma (MM) after stem cell transplantation (SCT) or successful chemotherapy. However, their clinical relevance remains unclear. We reviewed the clinical records of MM patients from January 2006 to May 2014. Treatment response was evaluated by International Working Group (IMWG) criteria. Serum immunofixation tests were performed at least every 3 months if the patient achieved more than very good partial response (VGPR). Free light chain (FLC) and minimal residual disease measurement by multicolor flow cytometry (MFC) were performed to evaluate the response to treatment. Among the 163 patients included in the study, 40 developed OB. Detection rates of OB in patients with complete response (CR), VGPR and partial response (PR) or less were 51.8, 36.3 and 0%, respectively. Patients with OB showed better progression‐free survival (PFS) and overall survival (OS) rates than those without OB (P = 0.028 and P < 0.001, respectively). However, if the patients were limited to ≥VGPR or CR, development of OB did not affect PFS (P = 0.621 and P = 0.646, respectively) or OS (P = 0.189 and P = 0.766, respectively). OB was observed in 60% of patients after SCT, and in 36.6% of patients with more than VGPR without SCT (P < 0.001). Patients with OB tended to have less minimal residual disease than those without OB (P = 0.054) and its presence may affect the stringent CR criteria. In conclusion, the emergence of OB was seen exclusively in patients with favorable responses, but its emergence per se could not be translated to improved survival.
α-Galactosylceramide stimulates splenic lymphocyte proliferation in vitro and increases antibody production in vivo in late neonatal-age mice
Authors: Chen Q , Ross A C
Published: September 2014

The neonatal stage is characterized by weak responses to various infections and vaccines, thus the development of efficient formulas to improve vaccine effectiveness is of high priority. The glycolipid alpha galactosylceramide (αGalCer) is known as a potent immune modulator due mainly to natural killer (NK) T cell activation. Using a mouse tetanus toxoid (TT) immunization model, we observed that neonatal mice given αGalCer at the time of primary immunization on postnatal day (pnd) 17 had a significantly higher TT-specific immunoglobulin (Ig)M response as well as a memory IgG response, while αGalCer given on pnd 7 resulted in only marginal boosting. Consistently, immunostaining of the spleen sections from αGalCer-treated pnd 17 immunized neonates showed a higher number of Ki67+ cells in the splenic germinal centre area, suggesting a stronger response after immunization. In-vitro kinetic studies revealed that spleen cells from newborn to pnd 7 neonates did not respond to αGalCer stimulation, whereas cell proliferation was increased markedly by αGalCer after pnd 7, and became dramatic around neonatal pnd 17–18, which was accompanied by increased B, T and NK T cell populations in the spleen. In addition, in pnd 17 spleen cells, αGalCer significantly stimulated the production of NK T cytokines, interleukin (IL)-4 and interferon (IFN)-γ, and promoted the proliferation of CD23+B cells, a subset of B cells enriched in germinal centres. These data suggest that αGalCer is an effective immune stimulus in the late neonatal stage, and thus may be useful in translational studies to test as a potential adjuvant to achieve a more efficient response to immunization.
Zinc transporter 8 (ZnT8) autoantibody epitope specificity and affinity examined with recombinant ZnT8 variant proteins in specific ZnT8R and ZnT8W autoantibody-positive type 1 diabetes patients
Authors: Skärstrand H , Krupinska E , Haataja T J K , Vaziri-Sani F , Lagerstedt J O , Lernmark Å
Published: September 2014

Variant-specific zinc transporter 8 autoantibodies (ZnT8A) against either arginine (R) or tryptophan (W) at amino acid (aa) position 325 of the zinc transporter 8 (ZnT8) has been identified in type 1 diabetes (T1D) patients. Reciprocal cross-over tests revealed differences in half-maximal binding to indicate variable affinity of patient ZnT8 autoantibodies. Insufficient recombinant ZnT8 variant proteins have precluded detailed analyses of ZnT8 autoantibody affinity. The aims in the present study were to (i) generate recombinant ZnT8R- and ZnT8W-aa275-369 proteins; (ii) test the ZnT8R- and ZnT8W-aa275-369 proteins in reciprocal competitive radiobinding assays (RBA) against ZnT8R- and ZnT8W-aa268-369 labelled with 35S-methionine; and (iii) determine the specificity and affinity of sera specific for either ZnT8 arginine (R) or ZnT8 tryptophan (W) autoantibodies in newly diagnosed T1D patients. The results demonstrate, first, that it was possible to produce recombinant human MBP–ZnT8-aa275-369 protein purified to homogeneity for RBA reciprocal competition experiments. Secondly, high-titre ZnT8WA sera diluted to half maximal binding showed significant specificity for respective variants of either ZnT8R or ZnT8W. Thirdly, ZnT8WA-positive sera showed high affinity for ZnT8W compared to ZnT8RA for ZnT8R. These data demonstrate that T1D patients may have single amino acid-specific autoantibodies directed against either ZnT8R or ZnT8W and that the autoantibody affinity to the respective variant may be different. Further studies are needed to assess the mechanisms by which variant-specific ZnT8A of variable affinity develop and their possible role in the pathogenic process leading to the clinical onset of T1D.
An Accuracy Study of Computer‐Planned Implant Placement in the Augmented Maxilla Using Mucosa‐Supported Surgical Templates
Authors: Verhamme Luc M. , Meijer Gert J. , Bergé Stefaan J. , Soehardi Rik A. , Xi Tong , de Haan Anton F.J. , Schutyser Filip , Maal Thomas J.J.
Published: September 2014

Purpose

The purpose of this study was to determine the clinically relevant accuracy of implant placement in the augmented maxilla using computer planning and a mucosa‐supported surgical template.

Materials and Methods

Twenty‐five consecutive edentulous patients with an extreme maxillar alveolar ridge resorption were treated with a bone augmentation procedure. In a second stage, sixBrånemarkMkIII Groovy (NobelBiocare®,Zürich,Switzerland) implants were installed. Preoperatively, a cone beam computer tomography (CBCT) scan was acquired, followed by virtual implant planning and flapless implant placement using a surgical template. A postoperativeCBCTscan was acquired and registered to the preoperative scan. TheImplantPositionOrthogonalProjection validation method was applied to measure implant deviations in both the buccolingual and mesio‐distal plane. The influence of fixation pins and the position on the dental arch were investigated with regard to implant deviations, and rotations and translations of the surgical template.

Results

One hundred fifty implants were installed. In mesio‐distal direction, a mean implant deviation of 1.50 mm was scored at the implant tip, 1.27 mm at the shoulder, −0.60 mm in depth, as well as a mean deviation of angulation of 2.50°. In buccolingual direction, a mean implant deviation of 0.99 mm was found at the implant tip, 0.76 mm at the implant shoulder, −0.57 mm in depth, and a deviation of angulation of 2.48°. Of all implants, 53% was placed too superficial compared with the planning. The use of fixation pins and implant deviations in both buccal and mesial directions as also for rotations and translation of the surgical template showed statistically significant differences.

Conclusions

Computer‐aided implant planning showed to be a clinically relevant tool. However, this study emphasizes that the surgeon should take into account that deviations are larger compared with implant placement without augmentation procedure. Deviations are mainly caused by angulations and translations of the surgical template.
Peri‐Implantitis Associated with Type of Cement: A Retrospective Analysis of Different Types of Cement and Their Clinical Correlation to the Peri‐Implant Tissue
Authors: Korsch Michael , Walther Winfried
Published: September 2014

Background

The cementation of fixed implant‐supported dental restorations involves the risk of leaving excess cement in the mouth which can promote biofilm formation in the peri‐implant sulcus. As a result, an inflammation may develop.

Purpose

The aim of the present study was to investigate the clinical effect of two different luting cements on the peri‐implant tissue.

Materials and Methods

Within the scope of a retrospective clinical follow‐up study, the prosthetic structures of 22 patients with 45 implants were revised. In all cases, a methacrylate cement (Premier Implant Cement [PIC], Premier® Dental Products Company, Plymouth Meeting, PA, USA) had been used for cementation. In 16 additional patients with 28 implants, the suprastructures were retained with a zinc oxide‐eugenol cement (Temp Bond [TB], Kerr Sybron Dental Specialities, Glendora, CA, USA). These patients were evaluated in the course of routine treatment.

Results

In both populations, the retention time of the suprastructures was similar (TB 3.77 years, PIC 4.07 years). In the PIC cases, 62% of all implants had excess cement. In the TB cases, excess cement was not detectable on any of the implants. Bleeding on probing was significantly more frequent on implants cemented with PIC (100% with and 94% without excess cement) than on implants cemented with TB (46%). Pocket suppuration was observed on 89% of the PIC‐cemented implants with excess cement (PIC without excess cement 24%), whereas implants with TB were not affected by it at all. The peri‐implant bone loss was significantly greater in the PIC patients (with excess cement 1.37 mm, without excess cement 0.41 mm) than it was in the TB patients (0.07 mm).

Conclusion

The frequency of undetected excess cement depends essentially on the type of cement used. Cements that tend to leave more undetected excess have a higher prevalence for peri‐implant inflammation and cause a more severe peri‐implant bone loss.
The significance of parahippocampal high gamma activity for memory preservation in surgical treatment of atypical temporal lobe epilepsy
Authors: Kunii Naoto , Kawai Kensuke , Kamada Kyousuke , Ota Takahiro , Saito Nobuhito
Published: September 2014

Objective

Resective surgery for mesial temporal lobe epilepsy (MTLE) with a correspondent lesion has been established as an effective and safe procedure. Surgery for temporal lobe epilepsies with bilateral hippocampal sclerosis or without correspondent lesions, however, carries a higher risk of devastating memory decline, underscoring the importance of establishing the memory‐dominant side preoperatively and adopting the most appropriate procedure. In this study, we focused on high gamma activities (HGAs) in the parahippocampal gyri and investigated the relationship between memory‐related HGAs and memory outcomes after hippocampal transection (HT), a hippocampal counterpart to neocortical multiple subpial transection. The transient nature of memory worsening after HT provided us with a rare opportunity to compare HGAs and clinical outcomes without risking permanent memory disorders.

Methods

We recorded electrocorticography from parahippocampal gyri of 18 patients with temporal lobe epilepsy while they executed picture naming and recognition tasks. Memory‐related HGA was quantified by calculating differences in power amplification of electrocorticography signals in a high gamma range (60–120 Hz) between the two tasks. We compared memory‐related HGAs from correctly recognized and rejected trials (hit‐HGA and reject‐HGA). Using hit‐HGA, we determined HGA‐dominant sides and compared them with memory outcomes after HT performed on seven patients.

Results

We observed memory‐related HGA mainly between 500 and 600 msec poststimulus. Hit‐HGA was significantly higher than reject‐HGA. Three patients who had surgery on the HGA‐dominant side experienced transient memory worsening postoperatively. The postoperative memory functions of the other four patients remained unchanged.

Significance

Parahippocampal HGA was indicated to reflect different memory processes and be compatible with the outcomes of HT, suggesting that HGA could provide predictive information on whether the mesial temporal lobe can be resected without causing memory worsening. This preliminary study suggests a refined surgical strategy for atypical MTLE based on reliable memory lateralization.
Prevention of generalized tonic–clonic seizures in refractory focal epilepsy: A meta‐analysis
Authors: Hemery Claire , Ryvlin Philippe , Rheims Sylvain
Published: September 2014

Objectives

Secondary generalized tonic–clonic seizures (SGTCS) are among the most severe forms of seizures, and the main risk factor for sudden unexpected death in epilepsy (SUDEP). Whether some antiepileptic drugs (AEDs) might be more efficacious than others on SGTCS in patients with drug‐resistant focal epilepsy thus represents an important clinical issue for which no data are currently available.

Methods

We performed a meta‐analysis of randomized controlled trials of adjunctive AED in which information on efficacy outcomes (i.e., responder rate and/or frequency per 28 days relative to baseline) were available both for all seizure types and for SGTCS. The primary analysis evaluated the efficacy of AEDs on all types of seizure and on SGTCS by comparing the responder rates for AED and for placebo.

Results

Responder rate was available both for all seizure types and for SGTCS in 13 of the 72 eligible trials, evaluating 7 AEDs. Only three AEDs—lacosamide, perampanel and topiramate—showed greater efficacy than placebo. However, confidence intervals of relative risks overlapped for all AEDs but pregabalin, which demonstrated significantly lower efficacy than lacosamide, perampanel, and topiramate. Moreover, there was a nonsignificant trend toward a lower relative risk of responder rate for SGTCS than for all seizure types, which appeared related to a greater response to placebo for this outcome.

Significance

Indirect comparison of AEDs using randomized placebo‐controlled add‐on trials does not support robust differences between AEDs to prevent SGTCS. Alternative designs for evaluation of therapeutic interventions in patients at risk for SGTCS‐related complications are required.
Kinship in Entrepreneur Networks: Performance Effects of Resource Assembly in Africa
Authors: Khayesi Jane N. O. , George Gerard , Antonakis John
Published: September 2014

We examine the relationship among structural social capital, resource assembly, and firm performance of entrepreneurs in Africa. We posit that social capital primarily composed of kinship or family ties helps the entrepreneur to raise resources, but it does so at a cost. Using data drawn from small firms in Kampala, Uganda, we explore how shared identity among the entrepreneur's social network moderates the relationship between social capital and outcomes. A large network contributed a higher quantity of resources raised, but at a higher cost when shared identity was high. We discuss the implications of these findings for the role of family ties and social capital in resource assembly, with an emphasis on developing economies.
A Conditional Process Model Explaining Partnered Gay Men's Perceived Relationship Stability
Authors: van Eeden‐Moorefield Brad , Benson Kristen E.
Published: September 2014

This study tested a conceptual model that examined how relationship closeness links stigma consciousness to perceived relationship stability among partnered gay men. The study further examined how this link differs for those with lower, compared to higher, levels of internalized homophobia. Cross‐sectional data were drawn from an Internet‐based survey using a convenience sample of 176 partnered gay men. Results suggest that relationship closeness fully mediated, or accounted for, the link between stigma consciousness and relationship stability for those with low internalized homophobia, but only partial mediation was found among those with high internalized homophobia. For that group, stigma consciousness displayed a strong direct effect as well. Therefore, the absence of an expectation to be stereotyped or discriminated against for being gay plays an important role in helping partnered gay men with high internalized homophobia build strong partnerships more so than for those with low internalized homophobia.
“We're Very Careful …”: The Fertility Desires and Contraceptive Behaviors of Cohabiting Couples
Authors: Sassler Sharon , Miller Amanda J.
Published: September 2014

A growing proportion of nonmarital births are to cohabiting couples, though childbearing is more common among moderately educated cohabitors than among cohabiting college graduates. In this study reasons for social class divergence in fertility behavior are explored. Data are from semistructured interviews with 30 working‐class and 31 middle‐class cohabiting couples. The authors inquired about readiness for parenthood, contraceptive usage, and concurrence about childbearing plans and contraception. Middle‐class couples generally utilized the most effective methods, often relied on two methods, concurred regarding fertility goals, and reported contracepting consistently. Among the moderately educated, contraceptive utilization was lower and reliance on less effective methods greater; they expressed greater ambivalence about preventing conception and discussed contraception less than their middle‐class counterparts. Less educated respondents also mentioned forgetfulness and cost as reasons for sporadic contraceptive use. The study results highlight the need to deepen understanding of how relational processes and couple dynamics contribute to pregnancy avoidance or conception.