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Characterization of cutaneous and articular sensory neurons
Background: A wide range of stimuli can activate sensory neurons and neurons innervating specific tissues often have distinct properties. Here we used retrograde tracing to identify sensory neurons innervating the hind paw skin (cutaneous) and ankle/knee joints (articular), and combined immunohistochemistry and electrophysiology analysis to determine the neurochemical phenotype of cutaneous and articular neurons, as well as their electrical and chemical excitability.
Results: Immunohistochemistry analysis using RetroBeads as a retrograde tracer confirmed previous data that cutaneous and articular neurons are a mixture of myelinated and unmyelinated neurons, and the majority of both populations are peptidergic. In whole-cell patch-clamp recordings from cultured dorsal root ganglion neurons, voltage-gated inward currents and action potential parameters were largely similar between articular and cutaneous neurons, although cutaneous neuron action potentials had a longer half-peak duration. An assessment of chemical sensitivity showed that all neurons responded to a pH 5.0 solution, but that acid-sensing ion channel (ASIC) currents, determined by inhibition with the non-selective ASIC antagonist benzamil, were of a greater magnitude in cutaneous compared to articular neurons. 40 – 50% of cutaneous and articular neurons responded to capsaicin, cinnamaldehyde and menthol, indicating similar expression levels of TRPV1, TRPA1 and TRPM8 respectively. By contrast, significantly more articular neurons responded to ATP than cutaneous neurons.
Conclusion: This work makes a detailed characterization of cutaneous and articular sensory neurons, and highlights the importance of making recordings from identified neuronal populations: sensory neurons innervating different tissues have subtly different properties, possibly reflecting different functions.ISS was funded by an Erasmus for Graduate Students grant from the University of Coimbra. ZMAH and experiments were funded by an Arthritis Research Project Grant (Grant Reference 20930) to ESS. JDB was funded by a Corpus Christi College Study and Travel Grant. EStJS was funded by an Early Career Research Grant from the International Association for the Study of Pain. Thanks to Christoforos Tsantoulas for assistance with immunohistochemistry and members of the Smith lab for their technical assistance and help in preparing the manuscript.This is the final version of the article. It first appeared from SAGE via http://dx.doi.org/10.1177/174480691663638
Analysis of new high-precision transit light curves of WASP-10 b: starspot occultations, small planetary radius, and high metallicity
The WASP-10 planetary system is intriguing because different values of radius
have been reported for its transiting exoplanet. The host star exhibits
activity in terms of photometric variability, which is caused by the rotational
modulation of the spots. Moreover, a periodic modulation has been discovered in
transit timing of WASP-10 b, which could be a sign of an additional body
perturbing the orbital motion of the transiting planet. We attempt to refine
the physical parameters of the system, in particular the planetary radius,
which is crucial for studying the internal structure of the transiting planet.
We also determine new mid-transit times to confirm or refute observed anomalies
in transit timing. We acquired high-precision light curves for four transits of
WASP-10 b in 2010. Assuming various limb-darkening laws, we generated best-fit
models and redetermined parameters of the system. The prayer-bead method and
Monte Carlo simulations were used to derive error estimates. Three transit
light curves exhibit signatures of the occultations of dark spots by the planet
during its passage across the stellar disk. The influence of stellar activity
on transit depth is taken into account while determining system parameters. The
radius of WASP-10 b is found to be no greater than 1.03 Jupiter radii, a value
significantly smaller than most previous studies indicate. We calculate
interior structure models of the planet, assuming a two-layer structure with
one homogeneous envelope atop a rock core. The high value of the WASP-10 b's
mean density allows one to consider the planet's internal structure including
270 to 450 Earth masses of heavy elements. Our new mid-transit times confirm
that transit timing cannot be explained by a constant period if all literature
data points are considered. They are consistent with the ephemeris assuming a
periodic variation of transit timing...Comment: Accepted for publication in A&
How to ask sensitive questions in conservation: A review of specialized questioning techniques
Tools for social research are critical for developing an understanding of conservation problems and assessing the feasibility of conservation actions. Social surveys are an essential tool frequently applied in conservation to assess both people’s behaviour and to understand its drivers. However, little attention has been given to the weaknesses and strengths of different survey tools. When topics of conservation concern are illegal or otherwise sensitive, data collected using direct questions are likely to be affected by non-response and social desirability biases, reducing their validity. These sources of bias associated with using direct questions on sensitive topics have long been recognised in the social sciences but have been poorly considered in conservation and natural resource management.
We reviewed specialized questioning techniques developed in a number of disciplines specifically for investigating sensitive topics. These methods ensure respondent anonymity, increase willingness to answer, and critically, make it impossible to directly link incriminating data to an individual. We describe each method and report their main characteristics, such as data requirements, possible data outputs, availability of evidence that they can be adapted for use in illiterate communities, and summarize their main advantages and disadvantages. Recommendations for their application in conservation are given. We suggest that the conservation toolbox should be expanded by incorporating specialized questioning techniques, developed specifically to increase response accuracy. By considering the limitations of each survey technique, we will ultimately contribute to more effective evaluations of conservation interventions and more robust policy decisions
Crystal structures of two one-dimensional coordination polymers constructed from Mn2+ ions, chelating hexafluoro-acetylacetonate anions, and flexible bipyridyl bridging ligands
Original Russian Text © 2016 M. J. Plater, B. M. De Silva, M. R. St. J. Foreman, W. T. A. Harrison. The text was submitted by the authors in English. Zhurnal Strukturnoi Khimii, Vol. 57, No. 6, pp. 1230-1235, July-August, 2016.Peer reviewedPostprin
Estudo, projecto e análise comparativa de custos entre duas condições de fundação de um tanque hexano
No presente trabalho apresenta-se um estudo comparativo de duas opções de fundação (superficial e profunda) para um tanque de hexano, inserido numa bacia de retenção num complexo industrial. O estudo consiste na análise de projecto e dos custos dessas duas soluções de fundação, tendo em conta as condições geológicas e geotécnicas do local de implantação e as acções na estrutura do tanque e da fundação.
Antes de introduzir o estudo anteriormente referido apresenta-se uma breve introdução sobre os tanques, a sua evolução como estrutura de armazenamento de combustÃveis e seus derivados. Segue-se uma abordagem sobre os diversos tipos de fundações, referenciando as mais utilizadas nos tanques e a importância de um estudo geológico e geotécnico.
O estudo de caso apresentado neste trabalho começa com um enquadramento geral da obra, descrevendo a estrutura do tanque e os condicionalismos da sua localização em termos geológicos e geotécnicos. Segue-se a análise estrutural do tanque, que envolve modelos de cálculo simplificados e um modelo de elementos finitos desenvolvido em SAP2000, para os quais se explica como se quantificam as acções permanentes e variáveis.
Utilizando os resultados dos modelos antes referidos efectua-se o dimensionamento das duas opções de fundação de acordo com a regulamentação portuguesa para estruturas de betão armado, verificando-se os estados limites de segurança. O trabalho termina com uma análise comparativa de custos entre as duas opções de fundação
Implementation of a Toffoli Gate with Superconducting Circuits
The quantum Toffoli gate allows universal reversible classical computation.
It is also an important primitive in many quantum circuits and quantum error
correction schemes. Here we demonstrate the realization of a Toffoli gate with
three superconducting transmon qubits coupled to a microwave resonator. By
exploiting the third energy level of the transmon qubit, the number of
elementary gates needed for the implementation of the Toffoli gate, as well as
the total gate time can be reduced significantly in comparison to theoretical
proposals using two-level systems only. We characterize the performance of the
gate by full process tomography and Monte Carlo process certification. The gate
fidelity is found to be %.Comment: 4 pages, 5figure
SAMHD1 restricts HIV-1 infection in dendritic cells (DCs) by dNTP depletion, but its expression in DCs and primary CD4+ T-lymphocytes cannot be upregulated by interferons
BACKGROUND: SAMHD1 is an HIV-1 restriction factor in non-dividing monocytes, dendritic cells (DCs), macrophages, and resting CD4(+) T-cells. Acting as a deoxynucleoside triphosphate (dNTP) triphosphohydrolase, SAMHD1 hydrolyzes dNTPs and restricts HIV-1 infection in macrophages and resting CD4(+) T-cells by decreasing the intracellular dNTP pool. However, the intracellular dNTP pool in DCs and its regulation by SAMHD1 remain unclear. SAMHD1 has been reported as a type I interferon (IFN)-inducible protein, but whether type I IFNs upregulate SAMHD1 expression in primary DCs and CD4(+) T-lymphocytes is unknown. RESULTS: Here, we report that SAMHD1 significantly blocked single-cycle and replication-competent HIV-1 infection of DCs by decreasing the intracellular dNTP pool and thereby limiting the accumulation of HIV-1 late reverse transcription products. Type I IFN treatment did not upregulate endogenous SAMHD1 expression in primary DCs or CD4(+) T-lymphocytes, but did in HEK 293T and HeLa cell lines. When SAMHD1 was over-expressed in these two cell lines to achieve higher levels than that in DCs, no HIV-1 restriction was observed despite partially reducing the intracellular dNTP pool. CONCLUSIONS: Our results suggest that SAMHD1-mediated reduction of the intracellular dNTP pool in DCs is a common mechanism of HIV-1 restriction in myeloid cells. Endogenous expression of SAMHD1 in primary DCs or CD4(+) T-lymphocytes is not upregulated by type I IFNs
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Supporting older and younger adults’ memory for recent everyday events: a prospective sampling study using SenseCam
This study measured the effect of a wearable camera, SenseCam, on older and younger adults’ memories of recently experienced everyday events. Participants used SenseCam to prospectively sample events from a typical week, which they recalled two weeks later. Recall was cued by a self-generated title only (control condition), by the title and forward-order SenseCam images, or by the title and random-order SenseCam images. In the control condition, older and younger adults’ memories were comparably episodic, but older adults recalled more semantic details. Both forward- and random-order SenseCam images were associated with increased episodic and semantic recall in both groups, and there was a small but significant effect of temporal order favouring the forward-order condition. These findings suggest that SenseCam is effective in supporting retrieval of memory for recent events, and the results of the temporal order manipulation also shed light on the mechanism of SenseCam’s effect
BABIES WITH BRAIN DAMAGE WHO CAN NOT SWALLOW Surgical management
Background: Neonates with severe neurological impairment are often unable to swallow, necessitating gastrostomy for feeding. Because of the risk of developing severe reflux, this procedure is often associated with fundoplication. Objective: To assess the safety and efficacy of gastrostomy and Nissen fundoplication in 22 neonates with swallowing difficulties due to serious neurological impairment. Method: All children underwent an initial period of nasogastric feeding and after informed consent underwent gastrostomy and Nissen fundoplication. Results: There were no significant intraoperative complications. There were two cases of postoperative periostomy leakage. Of the 22 neonates 16 were alive four months after surgery. Six neonates died of complications due to underlying disease. Conclusion: We concluded that gastrostomy and Nissen fundoplication are safe procedures and help parents give a better care to these children.663B64164
Determination of the antimutagenicity of an aqueous extract of Rhizophora mangle L. (Rhizophoraceae), using in vivo and in vitro test systems
An aqueous extract of Rhizophora mangle L. bark is used as raw material in pottery making in the State of Espirito Santo, Brazil. This extract presents large quantities of tannins, compounds possessing antioxidant properties. Tannin antioxidant activity, as a plant chemical defense mechanism in the process of stabilizing free radicals, has been an incentive to studies on anti-mutagenicity. The present work aimed to evaluate possible antimutagenic activity of a R. mangle aqueous extract, using the Allium cepa test-system and micronuclear (MN) assay with blockage of cytokinesis in Chinese hamster ovary cells (CHO-K1). The Allium cepa test-system indicated antimutagenic activity against the damage induced by the mutagenic agent methyl methanesulfonate. A reduction in both MN cell frequency and chromosome breaks occurred in both the pre and post-treatment protocols. The MN testing of CHO-K1 cells revealed anti-mutagenic activity of the R. mangle extract against methyl methanesulfonate and doxorubicin in pre, simultaneous and post-treatment protocols. These results suggest the presence of phyto-constituents in the extract presenting demutagenic and bio-antimutagenic activities. Since the chemical constitution of Rhizophora mangle species presents elevated tannin content, it is highly probable that these compounds are the antimutagenic promoters themselves
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