bluuebunny/crossref_metadata_2025 huggingface dataset:
Association of interferon lambda‐1 with herpes simplex viruses‐1 and ‐2, Epstein–Barr virus, and human cytomegalovirus in chronic periodontitis
Authors: Muzammil  , Jayanthi D , Faizuddin Mohamed , Noor Ahamadi H.M.
Published: December 2015

Aim

Periodontal tissues facilitate the homing of herpes viruses that elicit the immune‐inflammatory response releasing the interferons (IFN). IFN lambda‐1 (λ1) can suppress the replication of viruses, and induces the antiviral mechanism. The aim of the present study was to evaluate the association between IFN‐λ1 and periodontal herpes viruses in the immunoregulation of chronic periodontal disease.

Methods

The cross‐sectional study design included 30 chronic periodontitis patients with a mean age of 42.30 ± 8.63 years. Gingival crevicular fluid collected was assessed for IFN‐λ1 using enzyme–linked immunosorbent assay and four herpes viruses were detected using multiplex polymerase chain reaction technique. IFN‐λ1 levels were compared between virus‐positive and ‐negative patients for individual and total viruses.

Results

Fifty per cent (n = 15) of patients were positive for the four herpes viruses together; 50% (n = 15), 30% (n = 9), 26.7% (n = 8), and 40% (n = 12) were positive for herpes simplex virus (HSV)‐1, Epstein–Barr virus, HSV‐2, and human cytomegalovirus, respectively. The mean concentrations of IFN‐λ1 in virus‐positive patients (14.38 ± 13.95) were lower than those of virus‐negative patients (228.26 ± 215.35). INF‐λ1 levels in individual virus groups were also lower in virus‐positive patients compared to virus‐negative patients, with P < 0.001.

Conclusions

These results suggest that IFN‐λ1 could have antiviral and therapeutic value against the viruses in the pathogenesis of chronic periodontitis.
Phylogenetic utility of LEAFY gene in Cinnamomum (Lauraceae): Gene duplication and polymerase chain reaction‐mediated recombination
Authors: Huang Jian‐Feng , Li Lang , Conran John G. , Li Jie
Published: December 2015

Low copy nuclear genes show great potential to provide phylogenetic information, but their use has been hampered by several inherent adverse factors. Polymerase chain reaction (PCR)‐mediated recombination ranks among these factors and occurs when high levels of similar paralogs for a low‐copy nuclear gene coexist within a single PCR amplification reaction. In this study, the LEAFY gene was cloned and sequenced for 63 Cinnamomum species and two copies of the second intron were found within species of the diploid sect. Cinnamomum. Although these two copies are very similar, they can be distinguished easily due to a specific ca. 47‐bp segment that is missing in the “short sequence” copy. The “long sequence” copy performed well in phylogenetic analysis of Cinnamomum and is largely consistent with phylogenetic relationships based on internal transcribed spacer region sequences. In contrast, the “short sequence” copy was problematic for phylogenetic reconstruction and PCR‐mediated recombination was detected in 20 of the 38 Cinnamomum species with two LEAFY copies. Thirty‐one recombinants were discriminated and the breakpoints suggested by the programs RDP3 and GARD were distributed randomly along the recombination sequences. This study shows that duplication in low‐copy nuclear genes and problems associated with PCR‐mediated recombination need to be given more attention in phylogenetic studies.
Happiness Vs Contentment? A Case for a Sociology of the Good Life
Authors: McKenzie Jordan
Published: December 2015

Despite the enormous growth in happiness research in recent decades, there remains a lack of consistency in the use of the terms happiness, satisfaction, contentment and well‐being. In this article I argue for a sociologically grounded distinction between happiness and contentment that defines the former as positive affect and the latter as positive reflection. Contentment is therefore understood as a fulfilling relationship with the self and society (to borrow from G.H. Mead's terminology) and happiness involves pleasurable experiences. There is a history of similar distinctions in philosophy and psychoanalysis, but much of the contemporary discourse fails to distinguish between individual and collective definitions of happiness. This article will argue that happiness and contentment ought not to be treated as competing approaches to the good life, but as complimentary forms of emotional experience. Further, I argue that the current interest in happiness can be linked to larger culture shifts involving neoliberalism and individualism.
Differential introgression and reorganization of retrotransposons in hybrid zones between wild wheats
Authors: Senerchia Natacha , Felber François , North Béatrice , Sarr Anouk , Guadagnuolo Roberto , Parisod Christian
Published: December 2015

The maintenance of species integrity despite pervasive hybridization is ruled by the interplay between reproductive barriers. Endogenous postzygotic isolation will shape the patterns of introgression in hybrid zones, leading to variable outcomes depending on the genetic mechanism involved. Here, we analysed experimental and natural hybrid populations ofAegilops geniculataandAegilops triuncialisto examine the genetics of species boundaries in the face of gene flow. Because long‐terminal repeat retrotransposons (LTR‐RTs) showing differential evolutionary trajectories are probably to affect hybrid dysgenesis and reproductive isolation between these wild wheat species, we addressed the impact ofLTR‐RTs in shaping introgression between them. Experimental settings involving artificial sympatry and enforced crossings quantified strong, but incomplete reproductive isolation, and highlighted asymmetrical endogenous postzygotic isolation between the two species. Natural hybrid zones located in the northern Golan Heights were analysed using plastidDNA, amplified fragment length polymorphisms (AFLP) marking random sequences, and sequence‐specific amplified polymorphisms (SSAP) tracking insertions from sixLTR‐RTfamilies. This analysis demonstrated asymmetrical introgression and genome reorganization. In comparison with random sequences and quiescentLTR‐RTs, thoseLTR‐RTs predicted to be activated following conflicting interactions in hybrids revealed differential introgression across the hybrid zones. As also reported for synthetic F1 hybrids, suchLTR‐RTs were specifically reorganized in the genomes of viable hybrids, confirming that conflicts between selfishLTR‐RTs may represent key incompatibilities shaping species boundaries and fostering long‐term species integrity in the face of gene flow.
Space invaders – A netnographic study of how artefacts in nursing home environments exercise disciplining structures
Authors: Salzmann‐Erikson Martin
Published: December 2015

This study aims to present culturally situated artefacts as depicted in nursing home environments and to analyse the underlying understandings of disciplining structures that are manifested in these kinds of places. Our personal geographies are often taken for granted, but when moving to a nursing home, geographies are glaringly rearranged. The study design is archival and cross‐sectional observational, and the data are comprised of 38 photographs and 13 videos showing environments from nursing homes. The analysis was inspired by the methodological steps in Roper's and Shapira's description of conducting ethnography. The results are presented in four categories: (i) public areas, (ii) orderliness, (iii) staff's places and (iv) devices. The rearrangement of geography implies a degrading of agency and loss of authority over one's place. The places should be understood in their relation to the agents and their temporarily claims upon them. The material and immaterial artefacts, that is the items, people and behaviours, transform the nursing staff into ‘space invaders’. Future inquiries may take into consideration the ways that space invasion in participative space intersect and construct the identities of the agents it invades upon.
Against Welfare Subjectivism
Authors: Lin Eden
Published: December 2015

Subjectivismabout welfare is the view that something is basically good (bad) for you if and only if, and to the extent that, you have the right kind of favorable (disfavorable) attitude toward it under the right conditions. I make a presumptive case for the falsity of subjectivism by arguing against nearly every extant version of the view. My arguments share a common theme: theories of welfare should be tested for what they imply about newborn infants. Even if a theory is intended to apply only to adults, the fact that it is false of newborns may give us sufficient reason to reject it.
Noncoding and coding transcriptome responses of a marine diatom to phosphate fluctuations
Authors: Cruz de Carvalho Maria Helena , Sun Hai‐Xi , Bowler Chris , Chua Nam‐Hai
Published: December 2015

Phosphorus (P) is an essential element to all living cells, yet fluctuations in P concentrations are recurrent in the marine environment. Diatoms are amongst the most successful phytoplankton groups, adapting to and surviving periods of suboptimal conditions and resuming growth as soon as nutrient concentrations permit. A knowledge of the molecular underpinnings of diatom ecological success is, however, still very incomplete.

By strand‐specific RNA sequencing, we analyzed the global transcriptome changes of the diatom Phaeodactylum tricornutum in response to P fluctuations over a course of 8 d, defining five distinct physiological states.

This study reports previously unidentified genes highly responsive to P stress in P. tricornutum. Our data also uncover the complexity of the P. tricornutum P‐responsive sensory and signaling system that combines bacterial two‐component systems with more complex pathways reminiscent of metazoans. Finally, we identify a multitude of novel long intergenic nonprotein coding RNAs (lincRNAs) specifically responsive to P depletion, suggesting putative regulatory roles in the regulation of P homeostasis.

Our work provides additional molecular insights into the resilience of diatoms and their ecological success, and opens up novel routes to address and explore the function and regulatory roles of P. tricornutum lincRNAs in the context of nutrient stress.
EffectorP: predicting fungal effector proteins from secretomes using machine learning
Authors: Sperschneider Jana , Gardiner Donald M. , Dodds Peter N. , Tini Francesco , Covarelli Lorenzo , Singh Karam B. , Manners John M. , Taylor Jennifer M.
Published: December 2015

Eukaryotic filamentous plant pathogens secrete effector proteins that modulate the host cell to facilitate infection. Computational effector candidate identification and subsequent functional characterization delivers valuable insights into plant–pathogen interactions. However, effector prediction in fungi has been challenging due to a lack of unifying sequence features such as conserved N‐terminal sequence motifs. Fungal effectors are commonly predicted from secretomes based on criteria such as small size and cysteine‐rich, which suffers from poor accuracy.

We present EffectorP which pioneers the application of machine learning to fungal effector prediction.

EffectorP improves fungal effector prediction from secretomes based on a robust signal of sequence‐derived properties, achieving sensitivity and specificity of over 80%. Features that discriminate fungal effectors from secreted noneffectors are predominantly sequence length, molecular weight and protein net charge, as well as cysteine, serine and tryptophan content. We demonstrate that EffectorP is powerful when combined with in planta expression data for predicting high‐priority effector candidates.

EffectorP is the first prediction program for fungal effectors based on machine learning. Our findings will facilitate functional fungal effector studies and improve our understanding of effectors in plant–pathogen interactions. EffectorP is available at http://effectorp.csiro.au.
Composition and toxigenic potential of the Fusarium graminearum species complex from maize ears, stalks and stubble in Brazil
Authors: Kuhnem P. R. , Ward T. J. , Silva C. N. , Spolti P. , Ciliato M. L. , Tessmann D. J. , Del Ponte E. M.
Published: December 2015

A large collection (n = 539) of Fusarium graminearum species complex (FGSC) isolates was obtained from Brazilian maize, and collections formed according to geography and maize part: (i) kernel (n = 110) from south and south‐central Brazil; (ii) stalk (n = 134) from Paraná state (south); and (iii) stubble (n = 295) from Rio Grande do Sul state (south). Species composition, identified using a multilocus genotype approach, was assessed separately in each collection due to differences in geographic sampling. Overall, three species were found: F. meridionale (Fmer; 67% prevalence) with the nivalenol (NIV) genotype, F. graminearum (Fgra; 19%) with the 15‐acetyl (A) deoxynivalenol (DON) genotype, and F. cortaderiae (Fcor; 14%) with the NIV (49/74) or the 3‐ADON (25/74) genotype. In kernels, Fmer was spread across all locations and Fgra and Fcor were found mostly at high elevation (>800 m a.s.l.). The majority (97·8%) of stalk isolates was assigned to Fmer; three were assigned to Fgra. In the stubble, Fmer was less dominant (53%), with a shift towards Fcor as the most frequent species at high elevation sites (>600 m a.s.l.). No differences in the mycelial growth rate were observed among isolates from each species grown at 15°C. Fgra grew faster at 25°C and Fmer showed the widest range of variation across the isolates at both temperatures. The survey data suggest that Fmer may outcompete other species on ears and stalks in comparison to stubble. Additional sampling that controls for other factors, as well as direct testing of aggressiveness on ears and stalk tissue, will be needed to fully evaluate this hypothesis.
An incubation perspective on social innovation: the London Hub – a social incubator
Authors: Nicolopoulou Katerina , Karataş‐Özkan Mine , Vas Christopher , Nouman Muhammad
Published: December 2015

In the context of incubators, particularly those that are driven to achieving social objectives, this paper investigates core processes that support the development of social innovation. Social innovation, as this paper argues, is underpinned by a new form of social collaboration and engagement built upon strong forms of sharing knowledge and learning. Coupled with this is the element of social capital reinforced by entrepreneurship and leadership that promotes sustainability in the community. These factors drive innovative thinking and ways of engaging among stakeholders in order to create new forms of socio‐economic impact. Such value‐creating activity occurs in firms that operate within incubators involving a wide range of stakeholders who work through networks to co‐create and meet social challenges. Through a case study of a social incubator and an incubatee, we demonstrate the core processes that irradiate the argument on social innovation. The contribution of this paper is threefold: First, social innovation is an emerging area of research, of which there is a dearth in terms of examining the processes empirically. We address the gap in this field by demonstrating the value of social collaboration and engagement using different innovation models. Second, we establish links between social innovation and incubation using the concept of social capital. This allows us to achieve our third contribution: exemplification of a dyadic value‐based partnership and collaboration processes between an incubator and an incubatee, through activities driven by social innovation that aim to have social impact. The paper concludes with practice implications and suggests directions for future research.
Does More Balanced Survey Response Imply Less Non-Response Bias?
Authors: Schouten Barry , Cobben Fannie , Lundquist Peter , Wagner James
Published: December 2015

Recently, various indicators have been proposed as indirect measures of non-response error in surveys. They employ auxiliary variables, external to the survey, to detect non-representative or unbalanced response. A class of designs known as adaptive survey designs maximizes these indicators by applying different treatments to different subgroups. The natural question is whether the decrease in non-response bias that is caused by adaptive survey designs could also be achieved by non-response adjustment methods. We discuss this question and provide theoretical and empirical considerations, supported by a range of household and business surveys. We find evidence that more balanced response coincides with less non-response bias, even after adjustment.
Heat‐acclimatization and pre‐cooling: a further boost for endurance performance?
Authors: Schmit C. , Le Meur Y. , Duffield R. , Robach P. , Oussedik N. , Coutts A. J. , Hausswirth C.
Published: December 2015

To determine if pre‐cooling (PC) following heat‐acclimatization (HA) can further improve self‐paced endurance performance in the heat, 13 male triathletes performed two 20‐km cycling time‐trials (TT) at 35 °C, 50% relative humidity, before and after an 8‐day training camp, each time with (PC) or without (control) ice vest PC. Pacing strategies, physiological and perceptual responses were assessed during each TT. PC and HA induced moderate (+10 ± 18 W; effect size [ES] 4.4 ± 4.6%) and very large (+28 ± 19 W; ES 11.7 ± 4.1%) increases in power output (PO), respectively. The overall PC effect became unclear after HA (+4 ± 14 W; ES 1.4 ± 3.0%). However, pacing analysis revealed that PC remained transiently beneficial post‐HA, i.e., during the first half of the TT. Both HA and PC pre‐HA were characterized by an enhanced PO without increased cardio‐thermoregulatory or perceptual disturbances, while post‐HA PC only improved thermal comfort. PC improved 20‐km TT performance in unacclimatized athletes, but an 8‐day HA period attenuated the magnitude of this effect. The respective converging physiological responses to HA and PC may explain the blunting of PC effectiveness. However, perceptual benefits from PC can still account for the small alterations to pacing noted post‐HA.
“I'm Not Good Enough for Anyone”: Legal Status and the Dating Lives of Undocumented Young Adults
Authors: Pila Daniela
Published: December 2015

The impact of legal status on romantic relationships has not been adequately explored in the literature. Based on video and phone interviews with 25 undocumented activists from the ages of 18 to 28 years old, this research examines how legal status affects the romantic relationships of undocumented women and men. The hegemony of traditional dating scripts made it difficult for those without legal status to participate. Gender roles were consistent with stereotypical male and female roles in dating, which often attribute more power and responsibility to men. As such, women experienced a slight advantage because traditional notions of courtship did not require them to provide the resources required for dating, such as money or transportation, which in contrast were commonly expected of the men. In contrast, women noted the difficulties of disclosing their legal status and depending on their partners for everyday activities. Additionally, both men and women faced exclusion that inhibited their dating lives, as a direct result of their legal status. This suggests that the impact of legal status may be salient at all stages of family formation and that undocumented young adults are experiencing a distinct phenomenon compared to their documented and native‐born peers.
Outlier or Model of Austerity in Europe? The Case ofIrish Social Protection Reform
Authors: Dukelow Fiona , Considine Mairéad
Published: December 2015

This article analyses the evolution of theIrish economic crisis and its implications for social protection policy, specifically for working age adults, in the context ofEuropean integration andIreland's status as a small state member of theEU. We look at how neither small state characteristics, nor the position of small states in theEU, both of which raise problematic issues in their own right, are alone responsible forIreland's crisis situation. Such factors need to be understood in conjunction with national policy models and preferences which, in theIrish case, leant it something of an outlier status in theEU. Substantiating this argument and considering its implications for social protection reform, the article first examines the evolution ofIreland's liberal and increasingly financialized growth model in the context of greaterEuropean economic integration and how its risks intensified, but were also obscured, under Economic and Monetary Union (EMU). Second, against this backdrop and despite the growingEUrole in social policy, it examines how national policy factors meant that focus on income transfers remained dominant in social protection developments during the growth period spanning the mid‐1990s to 2008. Third, it analyses the unprecedented degree of social protection retrenchment and reform occurring since the crisis, highlighting the congruence between national efforts and the impact of conditionalities associated with financial assistance. The article concludes by considering the question of to what extentIreland will remain an outlier post‐crisis given the direction theEUhas taken in dealing with the Eurozone crisis to date.
Finite mixtures of censored Poisson regression models
Authors: Karlis Dimitris , Papatla Purushottam , Roy Sudipt
Published: December 2015

While right‐censored data are very common in survival analysis, they may also occur in the case of count data. The literature contains models to treat such right‐censored count data. In this paper, we want to address issues of heterogeneity and clustering in this context. We propose a finite mixture of censored Poisson regressions to accommodate heterogeneity and also identify clusters in right‐censored count data. We also develop an expectation maximization algorithm to facilitate the estimation of such models and discuss the computational aspects of the proposed algorithm. We then present results based on simulated data to show the effect of censoring in estimation. We also present a marketing application of the proposed approach involving the number of renewals of magazine subscriptions.
Spatial organization of cellulose microfibrils and matrix polysaccharides in primary plant cell walls as imaged by multichannel atomic force microscopy
Authors: Zhang Tian , Zheng Yunzhen , Cosgrove Daniel J.
Published: December 2015

We used atomic force microscopy (AFM), complemented with electron microscopy, to characterize the nanoscale and mesoscale structure of the outer (periclinal) cell wall of onion scale epidermis – a model system for relating wall structure to cell wall mechanics. The epidermal wall contains ~100 lamellae, each ~40 nm thick, containing 3.5‐nm wide cellulose microfibrils oriented in a common direction within a lamella but varying by ~30 to 90° between adjacent lamellae. The wall thus has a crossed polylamellate, not helicoidal, wall structure. Montages of high‐resolutionAFMimages of the newly deposited wall surface showed that single microfibrils merge into and out of short regions of microfibril bundles, thereby forming a reticulated network. Microfibril direction within a lamella did not change gradually or abruptly across the whole face of the cell, indicating continuity of the lamella across the outer wall. A layer of pectin at the wall surface obscured the underlying cellulose microfibrils when imaged byFESEM, but not byAFM. TheAFMthus preferentially detects cellulose microfibrils by probing through the soft matrix in these hydrated walls.AFM‐based nanomechanical maps revealed significant heterogeneity in cell wall stiffness and adhesiveness at the nm scale. By color coding and merging these maps, the spatial distribution of soft and rigid matrix polymers could be visualized in the context of the stiffer microfibrils. Without chemical extraction and dehydration, our results provide multiscale structural details of the primary cell wall in its near‐native state, with implications for microfibrils motions in different lamellae during uniaxial and biaxial extensions.
RhD negativity among pregnant women in multiethnic Suriname
Authors: Zonneveld Rens , Schmitz Peter , Eppink Jedda , Mac Donald M. Sigrid , Nahar‐van Venrooij Lenny M.W. , Kanhai Humphrey H.H. , Zijlmans Wilco C.W.R.
Published: December 2015

BACKGROUND

RhD negativity is distributed unevenly among different ethnicities. In this study we explored the frequencies of RhD negativity in pregnant women in multiethnic Suriname, along with screening results for red blood cell (RBC) antibodies in these women and their offspring. Results may help identify women at risk for hemolytic disease of the fetus and newborn.

STUDY DESIGN AND METHODS

A retrospective study was performed in pregnant women who delivered at three major hospitals in Suriname between January 1, 2013, and December 31, 2014.

RESULTS

The overall prevalences of RhD negativity among 8686 women was 4.3%. The percentages of RhD negativity in Maroons, Creoles, and Hindustani women were 7.2, 5.4, and 3.7%, respectively. Chinese and Javanese women had very low prevalences of 0.8 and 0.5%, respectively, and Amerindians showed no RhD negativity. Antibody screening was positive in six D– (five Maroons and one Creole) women and weakly positive in three women (two Creoles and one Maroon), making overall antibody prevalence 4.4%. In 15 (5.5%; 10 Maroons, four Creoles, one Chinese) newborns from D– mothers antibody screening was positive.

CONCLUSION

In the multiethnic Surinamese population RhD negativity among pregnant women varied between 0.0 and 7.2% between ethnic groups. RBC antibodies were detected during pregnancy and in newborns in 4.4 and 5.5%, respectively.
The Brauer group and indecomposable -cycles
Authors: Kahn Bruno
Published: December 2015

We show that the torsion in the group of indecomposable $(2,1)$-cycles on a smooth projective variety over an algebraically closed field is isomorphic to a twist of its Brauer group, away from the characteristic. In particular, this group is infinite as soon as $b_{2}-{\it\rho}>0$. We derive a new insight into Roǐtman’s theorem on torsion $0$-cycles over a surface.
INFLUENCE OF VASCULAR AND LUMEN FLOW ON SODIUM MOVEMENTS ACROSS ANURAN INTESTINE IN VITRO
Authors: Parsons D. S. , Wade S. A.
Published: December 2015

There is a positive linear relation between the vascular flow rate and the magnitudes of the unidirectional fluxes of Na in either direction in the steady state across the small intestine of the frog. Both unidirectional Na fluxes increase to the same extent with an increase in vascular flow so there is no apparent effect of flow on net Na movement. Raising the vascular flow rate in individual experiments increases the lumen‐blood Na flux proportionately, but reducing the flow from an initially high value reduces the lumen‐blood flux only slowly at first then more rapidly. The unidirectional Na fluxes increase linearly as the lumen flow rate is increased. In the colon increasing the vascular flow rate also increases the lumen‐blood Na flux but changing the vascular flow rate has little effect on the blood‐lumen flux, the net absorption of Na is invariably increased as the vascular flow increases. Using 14C‐labelled sucrose as a marker for the extracellular space of the small intestine, it can be shown that the increases in Na flux found with increased vascular flow rates are associated with an increase in this sucrose space. An increase in sucrose space, therefore, seems to enhance the accessibility of the low resistance, paracellular pathways for Na to and from the blood across the epithelium.
Enhancement by agonist or antagonist muscle vibration of tremor at the elastically loaded human elbow.
Authors: Cussons P D , Matthews P B , Muir R B
Published: December 2015

1. Human subjects attempted to maintain a constant force by flexing their elbow against a spring which was attached to a force transducer at one end and the subject's wrist at the other. The tremor at 8‐12 Hz which develops in this situation was enhanced in amplitude with negligible change of frequency by applying vibration at 100 Hz to the tendon either of an agonist muscle (biceps brachii) or of the antagonist (triceps brachii). The tremor was assessed by spectral analysis of the force records and measurement of the peaks in the spectra. The compliance of the spring was normally 2.8 N/mm and target forces of 40‐120 N were used. 2. The percentage increase in the tremor on applying vibration was relatively independent of target force, although the absolute amounts of tremor increased markedly with increasing target force. The average increase was greater for vibration of triceps than for biceps (70% as opposed to 37%, averaged between subjects and over a range of forces). 3. When the spring was replaced by a rigid connexion there was usually no clear tremor peak either in the presence or absence of vibration. Vibration, however, tended to increase the general noisiness of the force signal. 4. Qualitatively similar effects were seen when the elbow exerted an extending force so that triceps became the agonist and biceps the antagonist. 5. The tremor peak present in the spectrum of the demodulated electromyogram during vigorous tremor increased in size when vibration made the tremor larger. 6. The effect of a rhythmic afferent input was studied by modulating the amplitude of the vibration at 8‐9 Hz, to correspond to the tremor frequency, while the subject pulled against a rigid attachment. Both the e.m.g. and the tension spectra contained peaks at the modulation frequency. The raw force records showed that, with reference to the modulation, the effects of biceps and of triceps vibration were approximately 180 degrees out of phase with each other, as would occur if vibration of one were having an excitatory action, and vibration of the other an inhibitory action. Moreover, in each case the effect on force (whether excitatory or inhibitory) lagged about half a cycle on the vibration envelope, as required for such reflexes to help in the generation of tremor. 7. It is suggested that vibration increases the modulation of Ia firing elicited by a given movement tremor and this, by means of the stretch reflex arc, enhanced the tremor. The powerful action of vibration of the antagonist illustrates, it would seem, the functional effectiveness under normal conditions of a spinal inhibitory pathway, most probably the Ia disynaptic route. The findings are also discussed in relation to the increase in stretch reflex gain that occurs in association with increasing strength of voluntary contraction.
The afferent connexions and laminar distribution of cells in area 18 of the cat.
Authors: Harvey A R
Published: December 2015

1. The receptive field properties, laminar distribution and afferent connectivity of cells in area 18 of the cat are described. 2. Testing with both moving and stationary stimuli revealed three main receptive field types which have been termed S, C and B, respectively (cf. Henry, 1977; Henry, Lund & Harvey, 1978). All three classes may show end‐zone inhibition and units exhibiting this property have been designated SH, CH and BH. 3. S cells can be divided into spatially separate lights and/or dark edge response regions when tested with moving edges and usually have separate ON and/or OFF areas when tested with stationary flashing stimuli. They are the most commonly encountered cell type in area 18 and occur most frequently in laminae IIIb, IVa and VI. 4. Both C and B cells have spatially coincident light and dark edge response regions and give mixed ON and OFF discharges when tested with stationary flashing stimuli. Compared to B cells however, C cells have large receptive fields, they are broadly tuned for stimulus orientation and generally have a relatively high rate of spontaneous activity. C cells are more common than B cells and are encountered most often in laminae IVb and V. 5. Electrical stimulation of the optic chiasm (OX) and optic radiation (OR) was used to examine the afferent connectivity of parastriate neurons. Cells driven from both OX and OR have been divided into two main groups and it is argued that group 1 cells are directly, and group 2 cells are indirectly, excited by rapidly conducting afferent fibres. Group 1 cells are found most often in laminae IIIb, IVa, IVb and VI, and their distribution closely follows the anatomically defined laminar disposition of geniculocortical afferent terminals. Group 2 neurones predominate in laminae II‐IIIa, IIIA and V. 6. The majority of S and SH cells are directly driven, whereas most C and CH cells have OX and OR latencies suggestive of indirect activation by thalamic afferents. 7. The intrinsic organization and possible functional role of area 18 is discussed in the light of these results.
Control of fluid intake in pregnant and lactating rats.
Authors: Kaufman S
Published: December 2015

1. During 24 hr water deprivation, the pregnant and lactating rats lost more weight than the non‐mated animals. The increase in haematocrit was considerably greater in the lactating animals although plasma osmolality increased to the same extent in both lactating and non‐mated animals. 2. Following water deprivation, the water intake of the lactating rats was significantly less than that of the pregnant, post‐lactating or non‐mated animals when expressed as a percentage of the weight loss during dehydration. While the non‐mated rats restored their plasma osmolality to the pre‐deprivation value upon drinking, the lactating rats sustained a new decrease in osmolality despite the fact that their mean haematocrit was still elevated. 3. When the dehydrated animals were given isotonic saline to drink instead of water, both lactating and non‐mated animals restored their body weight and haematocrit to pre‐deprivation levels. 4. Lactating rats showed a reduced absolute and net fluid intake in response to I.V. hypertonic saline which could not be explained by more rapid renal clearance of the solute. 5. The pregnant and lactating rats drank less in response to s.c. isoprenaline than did the post‐lactating and non‐mated animals. 6. The spontaneous 3 hr fluid intake was significantly less during lactation. 7. It is suggested that during the hours of daylight, lactating rats are less responsive to dipsogenic stimuli arising from deficits in both their intracellular and extracellular fluid spaces.
Mouse pancreatic acinar cells: voltage‐clamp study of acetylcholine‐evoked membrane current.
Authors: McCandless M , Nishiyama A , Petersen O H , Philpott H G
Published: December 2015

1. A two‐micro‐electrode voltage‐clamp technique was applied to a study of the resting properties of mouse pancreatic acinar cell membranes and the action of acetylcholine (ACh). 2. The resting voltage‐current relation was linear. The specific membrane resistance was calculated to be about 10 k omega cm2. This value was doubled after removal of Cl from the tissue bath superfusion solution. 3. At a holding potential equal to the spontaneous resting potential (about ‐35 mV) micro‐ionophoretic ACh application evoked inward current. Reversal of the polarity of the ACh‐evoked current occurred at about ‐ 15 mV. 4. The voltage dependence of the ACh‐evoked current displayed inward rectification. This inward rectification could not be accounted for by the constant field equation. 5. The dose‐response curves for ACh‐evoked inward current were compared in the same units with dose‐response curves for ACh‐evoked depolarization. Half‐maximal depolarization was consistently obtained at a lower dose of ACh than half‐maximal inward current. 6. During steady‐state exposure of the pancreatic tissue segments to Cl‐free sulphate solution the ACh reversal potential was about + 10 mV and the voltage‐current relationship for the ACh‐controlled channels showed inward rectification. Removal of external Na from the Cl‐free solution virtually abolished ACh‐evoked inward current. 7. The resting pancreatic acinar cell membrane is electrically inexcitable. The relative permeabilities of the major monovalent ions appears to be PC1/PNa/PK = 2/0.23/1. The ACh‐evoked inward current is largely carried by Na. Dose‐response curves for ACh‐evoked depolarization and inward current in the same acinar units are different, in such a way that the depolarization response saturates at lower ACh concentrations than the current response.
Calcium transients in normal and denervated slow muscle fibres of the frog.
Authors: Miledi R , Parker I , Schalow G
Published: December 2015

1. Intracellular changes in free Ca2+ concentration were recorded from slow muscle fibres in the pyriformis muscle of Rana temporaria, using the dye arsenazo III. Fibres were voltage clamped, and arsenazo signals were recorded in response to depolarizing pulses. 2. The size of the arsenazo response to depolarizing pulses of 100 msec duration was a sigmoid function of membrane potential over the range ‐45 to 0 mV, and remained constant with further depolarizations up to +100 mV. 3. The peak size of the arsenazo signal to supramaximal depolarizations increased with increasing pulse length. The initial rising phase during a pulse was much slower than in twitch fibres, and this phase was followed by an even slower rise. Following short pulses the decay of the response was exponential, with a time constant of about 1.4 sec, while after long pulses the decline became much slower. 4. Decreasing free Ca2+ concentration in the bathing medium to very low levels, using EGTA , did not affect the responses to short (100 msec) depolarizations. 5. Slow fibres bathed in Ringer's solution containing 12 mM‐Ca2+ showed a well maintained arsenazo response to supramaximal depolarizations lasting over 1 min. Reduction of external Ca2+ to 1.8 and (nominally) 0 mM caused the response to become progressively more transient. 6. After denervation, slow fibres developed action potentials, but non of the parameters of the arsenazo response was significantly changed. During the early phase of reinnervation by a mixed nerve, when fast conduction axons begin to innervate slow fibres, the ability to give a maintained response during long depolarizations was reduced. 7. It is concluded that intracellular Ca2+ transients in slow muscle fibres are probably generated by a similar mechanism as in twitch fibres and entry of external Ca2+ is not an appreciable factor. The slow time course of the transients may be important in determining the time courses of tension development and relaxation.
Asymmetric charge movement in polarized and depolarized muscle fibres of the rabbit.
Authors: Lamb G D
Published: December 2015

1. The Vaseline‐gap technique was used to record asymmetric charge movement in single white sternomastoid fibres of the rabbit, both when the fibres were normally polarized (holding potential, ‐90 mV) and when they were subjected to prolonged depolarization (holding potential, 0 mV). 2. In normally polarized fibres, 10 microM‐nifedipine suppressed substantial charge movement (charge 1) without any prior depolarization, showing that the asymmetric charge does not have to be activated for the drug to exert its action. 3. Examination of the charge moved over a potential range from ‐140 to +10 mV confirmed that nifedipine affects only that charge generated at potentials more positive than ‐60 mV. 4. It was shown that there was charge movement in fibres subjected to prolonged depolarization (charge 2), with the greatest movement of charge occurring at about ‐71 mV, and that this charge was unaffected by nifedipine. 5. The total capacitive charge, that is, the sum of 'linear' capacitive and asymmetric charges, moved between ‐90 and ‐80 mV, was the same in polarized and depolarized fibres. Furthermore, the amount of asymmetric charge moved between potentials in the range ‐140 to ‐70 mV was the same in polarized and depolarized fibres. These observations indicate that the asymmetric charge moved between ‐140 and ‐70 mV in polarized fibres (charge 1) and depolarized fibres (charge 2) are in fact the same charge movement. 6. These results are inconsistent with the hypothesis that prolonged depolarization or nifedipine can cause a transition between charge 1 and charge 2. The results also suggest that the charge movement involved in calcium release may be quite different from that usually assumed.
Pulmonary stretch receptor relay neurones of the cat: location and contralateral medullary projections.
Authors: Davies R O , Kubin L , Pack A I
Published: December 2015

1. The activity of pump (p.) cells, second‐order neurones in the pulmonary stretch receptor pathway, was recorded extracellularly in the nucleus of the tractus solitarius (n.t.s.) of the decerebrate cat. Their firing was proportional to changes in lung volume but unrelated to the centrally determined respiratory rhythm. A systematic search of the n.t.s. for the location of p. cells was made and an assessment of their efferent projection to the contralateral n.t.s. was determined electrophysiologically by the antidromic mapping technique. 2. P. cells were located around, and in close proximity to, the solitary tract. The two sites of greatest density were ventromedial and dorsolateral to the tract, with lower concentrations found laterally and ventrolaterally. 3. For twelve of the thirty p. cells tested, evidence of a projection to the contralateral n.t.s. was obtained; in seven of these cells, axonal arborizations within the projection area were identified. Almost all the cells that sent axons to the contralateral n.t.s. were located dorsolateral to the tract; there was no evidence that cells in the ventromedial region had contralateral projections. 4. No evidence that R beta neurones project to the contralateral commissural and ventrolateral subnuclei was found. 5. No p. cells projected to the contralateral ventrolateral n.t.s. The site of projection and branching was consistently localized just caudal to the obex and medial to the solitary tract, in the caudal medial, and commissural subnuclei of the n.t.s. This same region has been shown to receive a dense, direct projection from pulmonary rapidly adapting receptors.
Induction of prolonged excitability in myometrium of pregnant guinea‐pigs by prostaglandin F2 alpha.
Authors: Coleman H A , Parkington H C
Published: December 2015

1. Electrical and mechanical responses to prostaglandin F2 alpha (PGF) were studied in circular myometrium, with or without endometrium, during the first 3 weeks of gestation of the guinea‐pig. 2. Muscle strips from which endometrium had been removed became inexcitable within 30‐40 min of isolation from the animal such that action potentials and contraction could not be initiated by depolarizing current steps. Raising the concentration of potassium in the perfusing solution resulted in a small contraction. 3. In these preparations PGF induced complex action potentials that consisted of spikes and a prolonged plateau of depolarization. Each action potential was associated with a large phasic contraction. 4. Contractions induced by PGF are unlikely to result predominantly from release of calcium from intracellular stores since the ability of the agonist to evoke a response was reduced by some 97% in the absence of external calcium or in the presence of calcium channel blockers. 5. When preceded by a brief exposure to PGF, the contractile response to high potassium was enhanced to equal that in response to PGF. Enhancement persisted for approximately 30 min after removal of PGF and was not dependent upon the presence of external calcium. 6. Muscle strips with intact endometrium contracted spontaneously for hours. Each contraction was associated with a complex action potential, both of which were abolished by indomethacin. 7. It is concluded that PGF transforms inexcitable calcium channels in the membrane of the smooth muscle cells of the circular myometrium into excitable ones. The study also suggests that endogenous prostaglandin of endometrial origin may prevent the 'run‐down' of channels in vivo.
Baroreceptor inputs to the nucleus tractus solitarius in the cat: modulation by the hypothalamus.
Authors: Mifflin S W , Spyer K M , Withington-Wray D J
Published: December 2015

1. The effects of stimulation within the hypothalamic defence area (HDA) on the activity of neurones in the nucleus of the solitary tract (NTS) have been investigated in vivo. 2. HDA stimulation exerted marked influences on NTS neurones. Approximately two‐thirds of units receiving a carotid sinus nerve (SN) input were inhibited by HDA stimulation. All units shown to receive an excitatory input from carotid sinus baroreceptors were inhibited by HDA stimulation. 3. The specificity of the HDA stimulation was investigated by generalized hypothalamic stimulation. In these experiments the number of units activated by SN stimulation that were inhibited was reduced considerably. A much smaller percentage (27%) of baroreceptive units were inhibited from hypothalamic stimulation outside the defence area. 4. Intracellular recordings revealed that HDA stimulation evoked a long‐lasting hyperpolarization of membrane potential that resulted from postsynaptic inhibition (rather than disfacilitation). The HDA‐evoked IPSP 'shunted' the SN‐evoked EPSP when the SN stimulus was timed to occur during the initial peak hyperpolarizing phase of the HDA‐evoked IPSP. 5. HDA stimulation disinhibited cells receiving an inhibitory input from the carotid sinus baroreceptors. 6. The effects of HDA stimulation were not limited to cells receiving SN afferent information or to cells within the NTS. 7. Our results explain, at the intracellular level, the mechanism for the central suppression of the baroreceptor reflex that forms an integral part of the defence response in the cat.
Calcium block of guinea‐pig heart sodium channels with and without modification by the piperazinylindole DPI 201‐106.
Authors: Nilius B
Published: December 2015

1. External Ca2+ block of Na+ channels was studied by a gigaohm‐seal patch clamp technique in single cardiac ventricular cells from guinea‐pig. Single‐channel currents were recorded from cell‐attached patches. 2. Increasing external Ca2+ concentrations in the patch pipette from 0.1 to 20 mM reduced the single‐channel conductance of normal Na+ channels from 27 to 14 pS without causing flickering (obtained from linear regression, eight patches). 3. Exposed to external Ca2+ concentrations of 20 mM, the single‐channel currents decreased at potentials negative to ‐60 mV in spite of an increased driving force for inward Na+ currents. 4. An external concentration of 35 mM‐Mg2+, which is supposed to exert a screening of surface charges nearly equal to that of 20 mM‐Ca2+ (Hille, Woodhull & Shapiro, 1975), reduced the single‐Na+‐channel conductance only from 26 (1 mM‐Mg2+) to 20 pS (linear regression, eight patches). A weaker voltage‐dependent block at potentials negative to ‐50 mV was observed in 35 mM‐Mg2+ than in 20 mM‐Ca2+. Therefore, surface charge effects cannot explain the obvious reduction of the conductance of single Na+ channels found when the external Ca2+ concentration was increased. 5. Single Na+‐channel currents increased with an increase in the external Na+ concentration [( Na+]o) but showed saturation. The Na+o‐single‐channel current relationship could be described by i = imax/(1 + kd/[Na+]o) with imax = 5.4 pA and kd = 359 mM (seventeen patches). 6. The mean open time of Na+ channels varied between 0.18 and 0.59 ms (potentials between ‐80 and ‐20 mV). No significant changes in the mean open time could be obtained when Ca2+ was varied between 0.1 and 20 mM. 7. The piperazinylindole compound DPI 201‐106 was used as a tool to prolong the open time of single Na+ channels. If the external Ca2+ concentration was increased from 0.1 to 20 mM the currents through the modified channels were reduced. The reduction of single‐channel currents was accentuated at potentials negative to ‐60 mV (20 mM‐Ca2+) similar to the control channels. 8. In contrast to non‐modified Na+ channels, the mean open time of DPI 201‐106‐modified channels proved extremely voltage and Ca2+ dependent.(ABSTRACT TRUNCATED AT 400 WORDS)