bluuebunny/crossref_metadata_2025 huggingface dataset:
Physics of Changes in Synoptic Midlatitude Temperature Variability
Authors: Schneider Tapio , Bischoff Tobias , Płotka Hanna
Published: December 2014

This paper examines the physical processes controlling how synoptic midlatitude temperature variability near the surface changes with climate. Because synoptic temperature variability is primarily generated by advection, it can be related to mean potential temperature gradients and mixing lengths near the surface. Scaling arguments show that the reduction of meridional potential temperature gradients that accompanies polar amplification of global warming leads to a reduction of the synoptic temperature variance near the surface. This is confirmed in simulations of a wide range of climates with an idealized GCM. In comprehensive climate simulations (CMIP5), Arctic amplification of global warming similarly entails a large-scale reduction of the near-surface temperature variance in Northern Hemisphere midlatitudes, especially in winter. The probability density functions of synoptic near-surface temperature variations in midlatitudes are statistically indistinguishable from Gaussian, both in reanalysis data and in a range of climates simulated with idealized and comprehensive GCMs. This indicates that changes in mean values and variances suffice to account for changes even in extreme synoptic temperature variations. Taken together, the results indicate that Arctic amplification of global warming leads to even less frequent cold outbreaks in Northern Hemisphere winter than a shift toward a warmer mean climate implies by itself.
Quality Assessment of HF Radar–Derived Surface Currents Using Optimal Interpolation
Authors: Fang Ying-Chih , Weingartner Thomas J. , Potter Rachel A. , Winsor Peter R. , Statscewich Hank
Published: December 2014

This study investigates the applicability of the optimal interpolation (OI) method proposed by Kim et al. for estimating ocean surface currents from high-frequency radar (HFR) in the northeastern Chukchi Sea, where HFR siting is dictated by power availability rather than optimal locations. Although the OI technique improves data coverage when compared to the conventional unweighted least squares fit (UWLS) method, biased solutions can emerge. The quality of the HFR velocity estimates derived by OI is controlled by three factors: 1) the number of available incorporating radials (AR), 2) the ratio of the incorporating radials from multiple contributing site locations [ratio of overlapping radial velocities (ROR) or radar geometry], and 3) the positive definiteness [condition number (CN)] of the correlation matrix. Operationally, ROR does not require knowledge of the angle covariance matrix used to compute the geometric dilution of precision (GDOP) in the UWLS method and can be computed before site selection to optimize coverage or after data processing to assess data quality when applying the OI method. The Kim et al. method is extended to examine sensitivities to data gaps in the radial distribution and the effects on OI estimates.
Urban Is Floating Face Down in the Mainstream
Authors: Irby Decoteau J.
Published: December 2014

Throughout this article, I argue that within the mainstream field of urban education, “the urban” is floating face down, lifeless, and devoid of significant meaning. “City” and “urban” function as taken-for-granted variables that stand in the rightful place of rich explanations, based in theory and evidence, of the city and its intersection with cultural transformations, pedagogies, movements, and knowledge(s) that comprise educational processes. To resurrect the urban concept, I present an overview of urban perspectives in two categories: old school (passive spatial theories) and new school (instrumental spatial theories). I highlight four recent urban education publications that reflect an emerging scholarly cypher on what I refer to as the urban education question. I then outline four spatial dimensions of hip hop and use these as a springboard for arguing that hip-hop pedagogues are uniquely positioned to be resurrectors of the urban concept. I conclude by exploring what such a theoretical pivot entails.
Functional and Morphological Olfactory Bulb Modifications in Mice after Vanadium Inhalation
Authors: Colín-Barenque Laura , Pedraza-Chaverri Jose , Medina-Campos Omar , Jimenez-Martínez Ruben , Bizarro-Nevares Patricia , González-Villalva Adriana , Rojas-Lemus Marcela , Fortoul Teresa I.
Published: December 2014

Neurodegenerative disorders, such as Parkinson’s and Alzheimer’s diseases, have olfaction impairment. These pathologies have also been linked to environmental pollutants. Vanadium is a pollutant, and its toxic mechanisms are related to the production of oxidative stress. In this study, we evaluated the effects of inhaled vanadium on olfaction, the olfactory bulb antioxidant, through histological and ultrastructural changes in granule cells. Mice in control group were made to inhale saline; the experimental group inhaled 0.02-M vanadium pentoxide (V2O5) for 1 hr twice a week for 4 weeks. Animals were sacrificed at 1, 2, 3, and 4 weeks after inhalation. Olfactory function was evaluated by the odorant test. The activity of glutathione peroxidase (GPx) and glutathione reductase (GR) was assayed in olfactory bulbs and processed for rapid Golgi method and ultrastructural analysis. Results show that olfactory function decreased at 4-week vanadium exposure; granule cells showed a decrease in dendritic spine density and increased lipofuscin, Golgi apparatus vacuolation, apoptosis, and necrosis. The activity of GPx and GR in the olfactory bulb was increased compared to that of the controls. Our results demonstrate that vanadium inhalation disturbs olfaction, histology, and the ultrastructure of the granule cells that might be associated with oxidative stress, a risk factor in neurodegenerative diseases.
Training Young Activists
Authors: Terriquez Veronica
Published: December 2014

This article examines how nonprofit activist youth groups shape the civic and political trajectories of their adolescent members. Based on analyses of survey and semi-structured interview data gathered from low-income, racially diverse, and immigrant alumni members of grassroots youth organizing groups and from a comparison sample, findings suggest that adolescent activist groups foster high levels of civic and political participation in early adulthood. Similar to other public-oriented volunteer associations—such as student government—activist groups impart civic skills and experiences that facilitate later involvement. Yet activist groups may function as particularly intensive training grounds for future participation by developing members’ political consciousness and engaging them in political processes. In spite of operating within a neoliberal context that sometimes inhibits the political activity of nonprofits, contemporary grassroots youth organizing groups, somewhat like the 1960s’ civil rights groups decades earlier, can propel some young people toward ongoing engagement with social movements.
Multiproxy approach for Holocene paleoenvironmental reconstructions from microorganisms (testate amoebae and foraminifera) and sediment analyses: The infilling of the Loire Valley in Nantes (France)
Authors: Delaine Maxence , Armynot du Châtelet Eric , Bout-Roumazeilles Viviane , Goubert Evelyne , Le Cadre Valérie , Recourt Philippe , Trentesaux Alain , Arthuis Rémy
Published: December 2014

Foraminifera and testate amoebae are jointly used with sediment characteristics (sediment size, calcium carbonate, C, H, N and S proportions, and clay mineralogy) to reconstruct the Holocene sediment infilling of the Loire estuary (Nantes, France). The results reveal the infilling of the Loire Valley during the Holocene. Deposited on the Hercynian substratum, the first deposits are made of gravels with rare associated fauna. This corresponds to the gravel lag usually present as basal deposits in the river course. The clay mineralogy indicates an erosion of the substratum. Then, from 8850 to 5850 cal. yr BP, estuarine fauna settled in a laminated sediment that alternates between clay and sand. The smectite associated with kaolinite and illite suggests increased input from the Sèvre Nantaise River. The fauna progressively shifts from estuarine to marine, indicating a rise in the sea level. From 5850 cal. yr BP, the pace of the sea level rise slowed and channels migrated, implying intense erosion. After 2100 cal. yr BP, the fauna was dominated by testate amoebae, indicating a continentalization of the environment. The top samples reflect recent human activity and urbanization.
Assessing the effectiveness of a cancer screening test in the presence of another screening modality
Authors: Chubak Jessica , Hubbard Rebecca A , Johnson Eric , Kamineni Aruna , Rutter Carolyn M
Published: December 2014

Objectives

Analysis of cancer screening effectiveness is challenging in part because of competing tests, which are additional screening tests that identify the condition of interest. For example, studies investigating screening with faecal occult blood tests to prevent colorectal cancer mortality need to consider the occurrence of screening colonoscopy. This paper compares analytic approaches to accounting for competing tests in analyses of cancer screening data.

Methods

We used simulations to compare bias and efficiency across approaches in different scenarios, quantify bias, and make recommendations for analyzing the effectiveness of a screening test in the presence of competing tests.

Results

Under all scenarios, the best performing approach for accommodating competing screening tests was censoring at the time of the competing screening test (range in bias across scenarios: −7.6% to 1.6%). Bias from other approaches ranged from 23.9% to 652.1%.

Conclusions

Censoring at the competing screening exam is the recommended approach for studying cancer screening effectiveness in the presence of competing tests. Censoring avoids confounding by prior competing test results and selection bias resulting from analyzing data on participants after they received a competing screening exam. Results from this study are broadly applicable to screening studies for other conditions, including other types of cancer.
SOD1 Function and Its Implications for Amyotrophic Lateral Sclerosis Pathology
Authors: Bunton-Stasyshyn Rosie K. A. , Saccon Rachele A. , Fratta Pietro , Fisher Elizabeth M. C.
Published: December 2014

The canonical role of superoxide dismutase 1 (SOD1) is as an antioxidant enzyme protecting the cell from reactive oxygen species toxicity. SOD1 was also the first gene in which mutations were found to be causative for the neurodegenerative disease amyotrophic lateral sclerosis (ALS), more than 20 years ago. ALS is a relentless and incurable mid-life onset disease, which starts with a progressive paralysis and usually leads to death within 3 to 5 years of diagnosis; in the majority of cases, the intellect appears to remain intact while the motor system degenerates. It rapidly became clear that when mutated SOD1 takes on a toxic gain of function in ALS. However, this novel function remains unknown and many cellular systems have been implicated in disease. Now it seems that SOD1 may play a rather larger role in the cell than originally realized, including as a key modulator of glucose signaling (at least so far in yeast) and in RNA binding. Here, we consider some of the new findings for SOD1 in health and disease, which may shed light on how single amino acid changes at sites throughout this protein can cause devastating neurodegeneration in the mammalian motor system.
The multi-level residue harmonic balance solutions of multi-mode nonlinearly vibrating beams on an elastic foundation
Authors: Hasan Abu Sufian MZ , Lee Yiu-yin , Leung Andrew Yee-Tak
Published: December 2014

In this paper, an efficient analytical solution method, namely, multi-level residue harmonic balance, is introduced and developed for the nonlinear vibrations of multi-mode flexible beams on an elastic foundation subject to external harmonic excitation. The main advantage of this solution method is that only one set of nonlinear algebraic equations is generated in the zero level solution procedure while the higher level solutions for any desired accuracy can be obtained by solving a set of linear algebraic equations. In other words, the computation effort to find more accurate nonlinear solutions is much less. In this paper, a multi-mode formulation, which represents the nonlinear beam vibration, is derived and set up. Then, the solution procedures are developed for obtaining the nonlinear multi-mode solution. The results from the multi-level residue harmonic balance method agree well with those from a numerical integration method. The effects of various parameters such as vibration amplitude, foundation modulus coefficient, damping factor and excitation level etc., on the nonlinear behaviors are examined. A convergence study is also performed to verify the solutions. The stability analysis is conducted using the virtue of Floquet theory and steady-state solutions are investigated.
Angular contact ball bearing experimental spall propagation observations
Authors: French Michael L , Hannon William M
Published: December 2014

Modern applications require bearings to survive in severe environments or when subjected to extreme loads and speeds. Some application designs require that a damaged bearing survives a specified duration. In particular, a clearer understanding of spall propagation in bearings may help design engineers prevent rapid damage propagation events and thereby minimize catastrophic failures. This paper summarizes the mechanics governing spall propagation in bearings. Two angular contact ball bearings, one with a seeded fault and the other damage-free, were studied experimentally. A broadband design of experiment approach was used to monitor bearing damage evolution, including demonstration of the effects of impact loading a rolling element on a spall front. The presented vibration, strain, deflection, and oil debris monitor (ODM) data span a matrix of loads and speeds. Results discuss the ball impact on the spall front and include supporting evidence of the following observations. The impact acceleration vector followed the contact angle. The outside diameter of the bearing raceway experienced 450 g rms (root-mean-square) acceleration even in the presence of a small surface defect. The vibration signal was substantially attenuated by the surrounding structure. The spall propagation strain energy was in the 15–30 kHz range and well above the fifth fundamental ball pass frequency. The strain energy associated with propagation decreased with thrust load while the ball pass strain increased.
Imperial ontological (in)security: ‘Buffer states’, International Relations and the case of Anglo-Afghan relations, 1808–1878
Authors: Bayly Martin J.
Published: December 2014

This article offers a new perspective on ‘buffer states’ — states that are geographically located between two rival powers — and their effect on international relations, with a particular focus on the imperial setting. The article argues that such geographic spaces have often been analysed through a structuralist-functionalist lens, which has, in some cases, encouraged ahistorical understandings on the role of buffer states in international affairs. In contrast, the article offers an approach borrowing from the literature on ontological security and critical geopolitics in order to access the meanings that such spaces have for their more powerful neighbours. The article draws upon the case study of Afghanistan and Anglo-Afghan relations during the 19th century and finds that, in this case, due to the ambiguity of Afghanistan’s status as a ‘state’, and the failure of British policymakers to establish routinized diplomatic engagement, Anglo-Afghan relations exhibited a sense of ontological insecurity for the British. These findings suggest previously unacknowledged international effects of ‘buffer states’, and may apply to such geographic spaces elsewhere.
A questionnaire survey comparing the educational priorities of patients and medical students in the management of multiple sclerosis
Authors: Gibson Jeremy C , Fakis Apostolos , Phillips Margaret F , Pinnington Lorraine L
Published: December 2014

Summary

Objective

To compare the educational priorities patients and students raise concerning the management of multiple sclerosis (MS).

Design/setting

A single-centre comparative questionnaire survey conducted in a foundation trust hospital which provides teaching for one UK medical school.

Participants

A total of 255 people with multiple sclerosis (pwMS) and 125 final year medical students attending a mandatory module were invited to participate.

Main outcome measurements

Questionnaires were developed and piloted for this study and analysed on the basis of the International Classification of Functioning, Disability and Health terminology.

Results

Questionnaires were returned by 125 (50%) pwMS (age range 36–86 years; median 58) and 96 (77%) medical students (age range 22–37 years; median 23). The most commonly reported priority listed by people with MS and students concerned ‘environmental contextual factors’ (95.5% and 99%, respectively). PwMS focused primarily on the ‘social and attitudinal aspects’ of the environment (53.6%), while students expressed greater interest in the use of medications (91.7%) and investigations (14.6%) ( p < 0.001). People with greater psychological or physical impact of the condition were more likely to prioritise ‘health condition’ topics.

Conclusions

PwMS and medical students identify different topics when asked to list aspects of management of MS which they deem to be important for medical student teaching. These differences in educational priorities should be taken into consideration when teaching students about MS. The findings may also apply to other long-term neurological conditions and warrant further investigation.
Book Review: Ajay K. Mehra (ed.), Party System in India: Emerging Trajectories
Authors: Sarangi Asha
Published: December 2014

Ajay K. Mehra (ed.), Party System in India: Emerging Trajectories. New Delhi: Lancer Publishers. 2013. 533 pages. ₹ 995.
Enhanced ethanol production and reduced glycerol formation in fps1∆ mutants of Saccharomyces cerevisiae engineered for improved redox balancing
Authors: Navarrete Clara , Nielsen Jens , Siewers Verena
Published: December 2014

Ethanol is by volume the largest fermentation product. During ethanol production by Saccharomyces cerevisiae about 4-5% of the carbon source is lost to glycerol production. Different approaches have been proposed for improving the ethanol yield while reducing glycerol production. Here we studied the effect of reducing glycerol export/formation through deletion of the aquaglyceroporin gene FPS1 together with expressing gapN encoding NADP+-dependent non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase from Streptococcus mutans and overexpressing the ATP-NADH kinase gene UTR1 from S. cerevisiae. This strategy will allow reducing the redox balance problem observed when the glycerol pathway is blocked, and hereby improve ethanol production. We found that our strategy enabled increasing the ethanol yield by 4.6% in the case of the best producing strain, compared to the reference strain, without any major effect on the specific growth rate.
Performance evaluation of a scoria-compost biofilter treating xylene vapors
Authors: Amin Mohammad Mehdi , Rahimi Amir , Bina Bijan , Heidari Mohsen , Mohammadi Moghadam Fazel
Published: December 2014

The removal of xylene vapors was studied in a biofilter packed with a new hybrid (scoria/compost) packing material at various inlet loads (IL) and empty bed residence times (EBRT) of 90, 60, and 40s. The best performance was observed for EBRT of 90s, where a removal efficiency of 98% was obtained under steady state condition for inlet xylene concentration of 1.34 g m−3, while a maximum elimination capacity of 97.5 g m−3 h−1 was observed for IL of 199.5 g m−3 h−1. Carbon dioxide production rates and the microbial counts for xylene-degraders followed xylene elimination capacities. Overall look to the results of this study indicates that the scoria/compost mixture could be considered as a potential biofilter carrier, with low pressure drop (here <4 mm H2O), to treat air streams containing VOCs.
Diffusional coupling between microfractures and pore structure and its impact on nuclear magnetic resonance measurements in multiple-porosity systems
Authors: Chi Lu , Heidari Zoya
Published: December 2014

Nuclear magnetic resonance (NMR) relaxation time measurements, although among the most accurate methods to estimate formation porosity, have been considered conventionally as insensitive to the presence of microfractures. Hence, the NMR responses in multiple-porosity systems, which may contain intergranular pores, microfractures, or channel-like inclusions, have not yet been thoroughly investigated. NMR pore-scale simulations using a random-walk algorithm enabled us to quantify the impact of microfractures/channels on NMR measurements and to propose a new concept of fracture-pore diffusional coupling in such heterogeneous systems. We randomly distributed and oriented microfractures (or channels) in 3D pore-scale images of different rock matrices. We then quantified the sensitivity of NMR [Formula: see text] (spin-spin relaxation time) distribution to the presence of microfractures (or channels) and compared the pore-scale simulation results against a previously published experimental study. The pore-scale simulation results from synthetic rock samples revealed that NMR [Formula: see text] distribution can be influenced not only by the pore-size distribution but also significantly by fracture-pore diffusional coupling. The intergranular pore size can be underestimated by up to 29%, and the volume fraction of intergranular pores can be underestimated by more than 10%, if the impact of diffusional coupling was not taken into account in interpretation of NMR measurements. Furthermore, we developed a simplified 1D analytical model for fracture-pore diffusional coupling. The analytical solutions of the 1D model were in agreement with the simulation results in the synthetic rock samples, which further demonstrated the existence of fracture-pore coupling in multiple-porosity systems. The developed 1D model enabled real-time evaluation of diffusional coupling effect in the presence of microfractures and complex pore-size distribution. The results were promising for future applications of NMR relaxometry for the assessment of microfracture content, when combined with other conventional well logs.
Permeability variation with porosity, pore space geometry, and cement type: A case history from the Snøhvit field, the Barents Sea
Authors: Grude Sissel , Dvorkin Jack , Landrø Martin
Published: December 2014

Laboratory permeability data from the brine-filled Tubåen Formation in the Snøhvit field show an order of magnitude permeability variation for approximately the same porosity. This variation in permeability is explained by a modified Kozeny-Carman equation that exploits the relationships among permeability, porosity, cementation, and pore geometry. The expression correlates the slope in a logarithmic plot of porosity versus permeability with the amount of contact cement and sorting, and the intercept with the grain size. Additional information about sorting and/or cementation can be used to better constrain the slope of the plot. Based on this equation, we found that the grain size and the amount of contact cement increased with depth in the lowermost Tubåen 1–3 sandstone units, this led to an increasing permeability with depth, in the same porosity range. The permeability variation in the shallowest Tubåen 4 sandstone unit was affected by sorting to a larger degree than the remaining Tubåen intervals, which influenced the cementation factor, porosity, and permeability simultaneously. These findings were supported by the depositional environment of the formation, a petrology study of grain size and sorting and a rock-physics study. The rock-physics study indicated that the samples with higher permeability had higher elastic moduli compared with the samples with lower permeability. This correlation between permeability and elastic moduli can be explained by the increasing amount of contact cement for the stiffer, high-permeability samples.
Elastic anisotropy of the Middle Bakken Formation
Authors: Sayers Colin M. , Dasgupta Sagnik
Published: December 2014

The Bakken Formation consists of three members: The Upper Bakken and Lower Bakken are dark marine shales with high organic content, whereas the Middle Bakken consists of mixed carbonates and clastics and is the main reservoir unit, despite having low porosity and permeability. Dipole S-wave data acquired in a lateral well in the Middle Bakken Formation revealed this formation to be anisotropic. Backus upscaling of logs acquired in a nearby vertical pilot well in the same layers sampled by the lateral well gave estimates of the anisotropy that were too small to explain the S-wave anisotropy measured in the lateral well. The observed anisotropy was interpreted in terms of bedding-parallel compliant discontinuities such as microcracks and low-aspect-ratio pores. The presence of bedding-parallel microcracks and low-aspect-ratio pores may contribute to the permeability of the tight Middle Bakken reservoir, and the sensitivity of P- and S-wave velocities to the presence of microcracks and low aspect ratio pores suggested the use of sonic and seismic measurements for identifying the productive zones in the low-permeability Middle Bakken reservoir.
Mårten Spångberg and the Vibe of Contemporaneity
Authors: Friedman Andrew
Published: December 2014

In this article, Andrew Friedman profiles the work of European choreographer and performance maker Mårten Spångberg, which he suggests trades in a radically expansive understanding of choreography in order to play with its perceptual experiences of “contemporaneity” and complicate easy consumerist habits of spectatorship promoted in neoliberal culture and media.
Evaluation of the Salt Content of Canned Sardines in Tomato Ketchup by Diffuse Reflection near Infrared Spectroscopy
Authors: Sirisomboon Panmanas , Pornchaloempong Pimpen , Ramsiri Peerawat , Pongkuan Skaow , Srikornkarn Sarocha
Published: December 2014

This research aimed to determine the salt content of canned sardines in tomato sauce using NIR spectroscopy compared with traditional methods employing an auto-titrator, which are more consuming in terms of time and chemicals used. Scanning of NIR radiation was performed using an FT-NIR spectrometer with a wavenumber range of 12,500–4000 cm−1 (800–2500 nm) with the diffuse reflection mode. Model development was achieved using partial least-squares regression from three groups of samples, which were the sample group that included salt-adjusted samples, the sample group that did not include salt-adjusted samples and the sample group that included only salt-adjusted samples plus five non-salt-adjusted samples. The model from the sample group that did not include salt-adjusted samples used the first derivative + straight-line subtraction spectra between 9403.8 cm−1 and 4242.9 cm−1 with nine partial least-squares factors providing the lowest root mean square error of prediction ( RMSEP), with a coefficient of determination of calibration ( R2) of 0.90, root mean square error of estimation of 0.039%, coefficient of determination for prediction ( r2) of 0.85, RMSEP of 0.046%, average error of prediction (bias) of −0.002% and ratio of standard error of validation to the standard deviation of 2.58. The sample group that included salt-adjusted samples had a skewed distribution. The model returned an RMSEP of 0.109% on test samples, but the performance-to-interquartile range index indicated that this was a poor calibration. For the smaller salt-adjusted samples plus five non-salt-adjusted samples, cross-validation indicated the potential to evaluate salt in canned sardines (root mean square error of cross-validation = 0.158%). It was found that the vibration of water had an effect on the prediction accuracy as well as the vibration of starch and protein. In addition, the CONH2 and CO2H groups, which are common amino acid functional groups, also showed an effect. These findings represent novel findings concerning the use of NIR spectroscopy to determine salt that has no signal of its own in the NIR region.
AN MCNP PARAMETRIC STUDY OF GEORGE C. LAURENCE'S SUBCRITICAL PILE EXPERIMENT
Authors: Dranga Ruxandra , Blomeley Laura , Carrington Rebecca
Published: December 2014

In the early 1940s at the National Research Council (NRC) Laboratories in Ottawa, Canada, Dr. George Laurence conducted several experiments to determine if a sustained nuclear fission chain reaction in a carbon–uranium arrangement (or “pile”) was possible. Although Dr. Laurence did not achieve criticality, these pioneering experiments marked a significant historical event in nuclear science, and they provided a valuable reference for subsequent experiments that led to the design of Canada’s first heavy-water reactors at the Chalk River Nuclear Laboratories.

This paper summarizes the results of a recent collaborative project between Atomic Energy of Canada Limited and the Deep River Science Academy undertaken to numerically explore the experiments carried out at the NRC Laboratories by Dr. Laurence, while teaching high school students about nuclear science and technology. In this study, a modern Monte Carlo reactor physics code, MCNP6, was utilized to identify and study the key parameters impacting the subcritical pile’s neutron multiplication factor (e.g., moderation, geometry, material impurities) and quantify their effect on the extent of subcriticality. The findings presented constitute the first endeavour to model, using a current computational reactor physics tool, the seminal experiment that provided the foundation of Canada’s nuclear science and technology program.
Letters
Authors: Plummer Anni , McNally S , Jones Menna Lloyd
Published: December 2014

I would like to reply and perhaps offer a different scenario to the editorial by Sarah Davies (Vol. 4(6) 1996, p.285).
Book reviews
Authors: Lovell Alice , Lindsay Julie
Published: December 2014

This revised edition has a wider remit than the 1991 version. As well as miscarriage, stillbirth and neonatal death, termination of pregnancy for whatever reason is included and information applicable to death in infancy.
Book Reviews
Authors: Reid Lindsay , South Angela May
Published: December 2014

This honest, very moving book has been written for parents who have suffered loss through the death of a baby. The issues examined are stillbirth and neonatal death with a particular look at the loss of babies who have been in a Special Care Baby Unit for some time.
1997 RCM Conference Review
Authors: Mead Marianne , Henderson Chris
Published: December 2014

I was very disappointed by the BJM's 1 L97 RCM Conference review (Vol. 5(6) 1 997. p.355) and believe that it does not do justice to the ethos which your journal has tried to develop.
Using silicone technology to maintain healthy skin in stoma care
Authors: White Maddie , Gough Claire , Howie Anne
Published: December 2014

The use of silicone in stoma care has grown in recent years and may be considered the next step in the revolutionary development of stoma-care products. Clinical nurse specialists aim to provide evidence-based care at all times, and the same is true for stoma-care nurses. Preventing harm by choosing products that have a sound research base provides the patients with up-to-date, quality care, which enables them to adapt to life with a stoma and return to ‘normal’ functioning. This article explores the issue of peristomal skin problems and the development of silicone products, and highlights scenarios where it could be an advantage to choose a silicone product.
Putting the patient at the heart of it all
Authors: Reyes Selena
Published: December 2014

Selena Reyes shares her thoughts on a recent conference that focused on improving the patient experience, and how two keynote speakers in particular have influenced her practice
NHS hospital complaints: going round in circles?
Authors: Tingle John
Published: December 2014

In this two-part column, John Tingle discusses the new report published by the Patients Association on the state of the NHS complaints system
The LIM Homeodomain Factor Lhx2 Is Required for Hypothalamic Tanycyte Specification and Differentiation
Authors: Salvatierra Juan , Lee Daniel A. , Zibetti Cristina , Duran-Moreno Maria , Yoo Sooyeon , Newman Elizabeth A. , Wang Hong , Bedont Joseph L. , de Melo Jimmy , Miranda-Angulo Ana L. , Gil-Perotin Sara , Garcia-Verdugo Jose Manuel , Blackshaw Seth
Published: December 2014

Hypothalamic tanycytes, a radial glial-like ependymal cell population that expresses numerous genes selectively enriched in embryonic hypothalamic progenitors and adult neural stem cells, have recently been observed to serve as a source of adult-born neurons in the mammalian brain. The genetic mechanisms that regulate the specification and maintenance of tanycyte identity are unknown, but are critical for understanding how these cells can act as adult neural progenitor cells. We observe that LIM (Lin-11, Isl-1, Mec-3)-homeodomain geneLhx2is selectively expressed in hypothalamic progenitor cells and tanycytes. To test the function ofLhx2in tanycyte development, we used an intersectional genetic strategy to conditionally deleteLhx2in posteroventral hypothalamic neuroepithelium, both embryonically and postnatally. We observed that tanycyte development was severely disrupted whenLhx2function was ablated during embryonic development.Lhx2-deficient tanycytes lost expression of tanycyte-specific genes, such asRax, while also displaying ectopic expression of genes specific to cuboid ependymal cells, such asRarres2. Ultrastructural analysis revealed that mutant tanycytes exhibited a hybrid identity, retaining radial morphology while becoming multiciliated. In contrast, postnatal loss of function ofLhx2resulted only in loss of expression of tanycyte-specific genes. Using chromatin immunoprecipitation, we further showed that Lhx2 directly regulated expression ofRax, an essential homeodomain factor for tanycyte development. This study identifiesLhx2as a key intrinsic regulator of tanycyte differentiation, sustainingRax-dependent activation of tanycyte-specific genes while also inhibiting expression of ependymal cell-specific genes. These findings provide key insights into the transcriptional regulatory network specifying this still poorly characterized cell type.
Independent Premotor Encoding of the Sequence and Structure of Birdsong in Avian Cortex
Authors: Basista Mark J. , Elliott Kevin C. , Wu Wei , Hyson Richard L. , Bertram Richard , Johnson Frank
Published: December 2014

How the brain coordinates rapid sequences of learned behavior, such as human speech, remains a fundamental problem in neuroscience. Birdsong is a model of such behavior, which is learned and controlled by a neural circuit that spans avian cortex, basal ganglia, and thalamus. The songs of adult male zebra finches (Taeniopygia guttata), produced as rapid sequences of vocal gestures (syllables), are encoded by the cortical premotor region HVC (proper name). While the motor encoding of song within HVC has traditionally been viewed as unitary and distributed, we used an ablation technique to ask whether the sequence and structure of song are processed independently within HVC. Results revealed a functional topography across the medial–lateral axis of HVC. Bilateral ablation of medial HVC induced a positive disruption of song (increase in atypical syllable sequences), whereas bilateral ablation of lateral HVC induced a negative disruption (omission of individual syllables). Bilateral ablation of central HVC either had no effect on song or induced syllable omission, similar to lateral HVC ablation. We then investigated HVC connectivity and found parallel afferent and efferent pathways that transit medial and lateral HVC and converge at vocal motor cortex. In light of recent evidence that syntactic and lexical components of human speech are processed independently by neighboring regions of cortex (Menenti et al., 2012), our demonstration of anatomically distinct pathways that differentially process the sequence and structure of birdsong in parallel suggests that the vertebrate brain relies on a common approach to encode rapid sequences of vocal gestures.
Odorant Concentration Differentiator for Intermittent Olfactory Signals
Authors: Fujiwara Terufumi , Kazawa Tomoki , Sakurai Takeshi , Fukushima Ryota , Uchino Keiro , Yamagata Tomoko , Namiki Shigehiro , Haupt Stephan Shuichi , Kanzaki Ryohei
Published: December 2014

Animals need to discriminate differences in spatiotemporally distributed sensory signals in terms of quality as well as quantity for generating adaptive behavior. Olfactory signals characterized by odor identity and concentration are intermittently distributed in the environment. From these intervals of stimulation, animals process odorant concentration to localize partners or food sources. Although concentration–response characteristics in olfactory neurons have traditionally been investigated using single stimulus pulses, their behavior under intermittent stimulus regimens remains largely elusive. Using the silkmoth (Bombyx mori) pheromone processing system, a simple and behaviorally well-defined model for olfaction, we investigated the neuronal representation of odorant concentration upon intermittent stimulation in the naturally occurring range. To the first stimulus in a series, the responses of antennal lobe (AL) projection neurons (PNs) showed a concentration dependence as previously shown in many olfactory systems. However, PN response amplitudes dynamically changed upon exposure to intermittent stimuli of the same odorant concentration and settled to a constant, largely concentration-independent level. As a result, PN responses emphasized odorant concentration changes rather than encoding absolute concentration in pulse trains of stimuli. Olfactory receptor neurons did not contribute to this response transformation which was due to long-lasting inhibition affecting PNs in the AL. Simulations confirmed that inhibition also provides advantages when stimuli have naturalistic properties. The primary olfactory center thus functions as an odorant concentration differentiator to efficiently detect concentration changes, thereby improving odorant source orientation over a wide concentration range.
Neuronal Transgene Expression in Dominant-Negative SNARE Mice
Authors: Fujita Takumi , Chen Michael J. , Li Baoman , Smith Nathan A. , Peng Weiguo , Sun Wei , Toner Michael J. , Kress Benjamin T. , Wang Linhui , Benraiss Abdellatif , Takano Takahiro , Wang Su , Nedergaard Maiken
Published: December 2014

Experimental advances in the study of neuroglia signaling have been greatly accelerated by the generation of transgenic mouse models. In particular, an elegant manipulation that interferes with astrocyte vesicular release of gliotransmitters via overexpression of a dominant-negative domain of vesicular SNARE (dnSNARE) has led to documented astrocytic involvement in processes that were traditionally considered strictly neuronal, including the sleep–wake cycle, LTP, cognition, cortical slow waves, depression, and pain. A key premise leading to these conclusions was that expression of the dnSNARE was specific to astrocytes. Inconsistent with this premise, we report here widespread expression of thednSNAREtransgene in cortical neurons. We further demonstrate that the activity of cortical neurons is reversibly suppressed in dnSNARE mice. These findings highlight the need for independent validation of astrocytic functions identified in dnSNARE mice and thus question critical evidence that astrocytes contribute to neurotransmission through SNARE-dependent vesicular release of gliotransmitters.
Human Subthalamic Nucleus in Movement Error Detection and Its Evaluation during Visuomotor Adaptation
Authors: Tan Huiling , Zavala Baltazar , Pogosyan Alek , Ashkan Keyoumars , Zrinzo Ludvic , Foltynie Thomas , Limousin Patricia , Brown Peter
Published: December 2014

Monitoring and evaluating movement errors to guide subsequent movements is a critical feature of normal motor control. Previously, we showed that the postmovement increase in electroencephalographic (EEG) beta power over the sensorimotor cortex reflects neural processes that evaluate motor errors consistent with Bayesian inference (Tan et al., 2014). Whether such neural processes are limited to this cortical region or involve the basal ganglia is unclear. Here, we recorded EEG over the cortex and local field potential (LFP) activity in the subthalamic nucleus (STN) from electrodes implanted in patients with Parkinson's disease, while they moved a joystick-controlled cursor to visual targets displayed on a computer screen. After movement offsets, we found increased beta activity in both local STN LFP and sensorimotor cortical EEG and in the coupling between the two, which was affected by both error magnitude and its contextual saliency. The postmovement increase in the coupling between STN and cortex was dominated by information flow from sensorimotor cortex to STN. However, an information drive appeared from STN to sensorimotor cortex in the first phase of the adaptation, when a constant rotation was applied between joystick inputs and cursor outputs. The strength of the STN to cortex drive correlated with the degree of adaption achieved across subjects. These results suggest that oscillatory activity in the beta band may dynamically couple the sensorimotor cortex and basal ganglia after movements. In particular, beta activity driven from the STN to cortex indicates task-relevant movement errors, information that may be important in modifying subsequent motor responses.
Sex Differences in the Brain's Dopamine Signature of Cigarette Smoking
Authors: Cosgrove Kelly P. , Wang Shuo , Kim Su-Jin , McGovern Erin , Nabulsi Nabeel , Gao Hong , Labaree David , Tagare Hemant D. , Sullivan Jenna M. , Morris Evan D.
Published: December 2014

Cigarette smoking is a major public health danger. Women and men smoke for different reasons and cessation treatments, such as the nicotine patch, are preferentially beneficial to men. The biological substrates of these sex differences are unknown. Earlier PET studies reported conflicting findings but were each hampered by experimental and/or analytical limitations. Our new image analysis technique, lp-ntPET (Normandin et al., 2012; Morris et al., 2013; Kim et al., 2014), has been optimized for capturing brief (lasting only minutes) and highly localized dopaminergic events in dynamic PET data. We coupled our analysis technique with high-resolution brain scanning and high-frequency motion correction to create the optimal experiment for capturing and characterizing the effects of smoking on the mesolimbic dopamine system in humans. Our main finding is that male smokers smoking in the PET scanner activate dopamine in the right ventral striatum during smoking but female smokers do not. This finding—men activating more ventrally than women—is consistent with the established notion that men smoke for the reinforcing drug effect of cigarettes whereas women smoke for other reasons, such as mood regulation and cue reactivity. lp-ntPET analysis produces a novel multidimensional endpoint: voxel-level temporal patterns of neurotransmitter release (“DA movies”) in individual subjects. By examining these endpoints quantitatively, we demonstrate that the timing of dopaminergic responses to cigarette smoking differs between men and women. Men respond consistently and rapidly in the ventral striatum whereas women respond faster in a discrete subregion of the dorsal putamen.
Hypoxia Inducible Factor-1α (HIF-1α) Is Required for Neural Stem Cell Maintenance and Vascular Stability in the Adult Mouse SVZ
Authors: Li Lu , Candelario Kate M. , Thomas Kelsey , Wang Ruth , Wright Kandis , Messier Amber , Cunningham Lee Anna
Published: December 2014

HIF-1α is a hypoxia-inducible protein that regulates many cell and molecular processes, including those involved in angiogenesis and stem cell maintenance. Prior studies demonstrated constitutive HIF-1α stabilization in neural stem cells (NSCs) of the adult mouse SVZ, but its role there has not been elucidated. Here, we tested the hypothesis that HIF-1α plays an essential role in the maintenance of adult NSCs and stabilization of the SVZ vascular niche using conditional, tamoxifen-inducibleHif1aknock-out mice. We generated nestin-CreERT2/R26R-YFP/Hif1afl/fltriple transgenic mice, to enable tamoxifen-inducibleHif1agene inactivation in nestin-expressing NSCs within the adult SVZ.Hif1agene deletion resulted in a significant loss of YFP+NSCs within the SVZ by 45 d post recombination, which was preceded by significant regression of the SVZ vasculature at 14 d, and concomitant decrease of VEGF expression by NSCs. Loss of YFP+NSCs followingHif1agene inactivationin vivowas likely an indirect consequence of vascular regression, since YFP+neurosphere formation over serial passage was unaffected. These results identify NSC-encoded HIF-1α as an essential factor in the maintenance of the adult SVZ, and demonstrate that NSCs within the SVZ maintain the integrity of their vascular niche through HIF-1α-mediated signaling mechanisms.
Phosphoproteomic analyses reveal novel cross‐modulation mechanisms between two signaling pathways in yeast
Authors: Vaga Stefania , Bernardo‐Faura Marti , Cokelaer Thomas , Maiolica Alessio , Barnes Christopher A , Gillet Ludovic C , Hegemann Björn , van Drogen Frank , Sharifian Hoda , Klipp Edda , Peter Matthias , Saez‐Rodriguez Julio , Aebersold Ruedi
Published: December 2014

Cells respond to environmental stimuli via specialized signaling pathways. Concurrent stimuli trigger multiple pathways that integrate information, predominantly via protein phosphorylation. Budding yeast responds to NaCl and pheromone via two mitogen‐activated protein kinase cascades, the high osmolarity, and the mating pathways, respectively. To investigate signal integration between these pathways, we quantified the time‐resolved phosphorylation site dynamics after pathway co‐stimulation. Using shotgun mass spectrometry, we quantified 2,536 phosphopeptides across 36 conditions. Our data indicate that NaCl and pheromone affect phosphorylation events within both pathways, which thus affect each other at more levels than anticipated, allowing for information exchange and signal integration. We observed a pheromone‐induced down‐regulation of Hog1 phosphorylation due to Gpd1, Ste20, Ptp2, Pbs2, and Ptc1. Distinct Ste20 and Pbs2 phosphosites responded differently to the two stimuli, suggesting these proteins as key mediators of the information exchange. A set of logic models was then used to assess the role of measured phosphopeptides in the crosstalk. Our results show that the integration of the response to different stimuli requires complex interconnections between signaling pathways.