Thermal field over Tibetan Plateau and Indian summer monsson rainfall

The interannual variability of the temperature anomalies over the Tibetan Plateau (25-45 °N, 75-105 °E) is examined in relation to the Indian summer monsoon rainfall (ISMR: June to September total rainfall). For this purpose, the temperature anomaly data of the central-eastern Tibetan Plateau is divided into three regions using principal component analysis and the ISMR data for the period 1957-89 have been used. It is found that the January temperature anomaly of Region 2 has a significant negative relationship (r = -0.67) with the ISMR of the subsequent season. This region is located over the northeastern part of the Tibetan Plateau, mostly in Qinghai province, including the Bayan Harr Mountain range and the Qaidam Basin. This relationship is consistent and robust during the period of analysis and can be used to predict the strength of the Indian summer monsoon in the subsequent season. It was found that the January temperature anomaly in this region was associated with a persistent winter circulation pattern over the Eurasian continent during January through to March. Finally, the variation patterns of the temperature anomalies in all three regions over the central-eastern Tibetan Plateau during extreme years of the ISMR are examined. It is concluded that the January temperature anomaly over the northeastern Tibetan Plateau can be useful in forecasting the drought and flood conditions over India, especially in predicting the monsoon rainfall over the areas lying along the monsoon trough

Bioactividad de los extractos y aislamiento de los lignanos de las semillas de Centaurea dealbata

Centaurea dealbata Willd. (Family: Asteraceae) belongs to the big genus Centaurea that comprises ca. 500 species. Then-hexane, dichloromethane (DCM) and methanol (MeOH) extracts of the seeds of C. dealbata have been assessed forantioxidant activity and general toxicity using, respectively, the DPPH assay, and the brine shrimp lethality assay. Boththe DCM and the MeOH extract showed signifi cant levels of antioxidant activities with an RC50 value 6.8 x 10-2 and4.7 x 10-2 mg/mL, respectively. None of the extracts exhibited any signifi cant general toxicity (LD50 = >1000 mg/mL).Three major bioactive components of the MeOH extract were found to be the lignans, arctigenin, arctiin and matairesinoside.The structures of these lignans were elucidated by comprehensive spectroscopic analyses, and also by directcomparison with the respective published data. This is the fi rst report on the occurrence of arctiin and matairesionl inC. dealbata. The distribution of these lignans within the genus Centaurea has also been presented.La Centaurea dealbata Willd. (familia: Asteraceae) pertenece al género Centaurea, que comprende unas 500 especies.Para evaluar la actividad antioxidante y la toxicidad general de los extractos de n-hexano, diclorometano (DCM)y metanol (MeOH) de las semillas de C. dealbata se han utilizado, respectivamente, el ensayo DPPH y el ensayo deletalidad de gambas en salmuera. Tanto el extracto de DCM como el de MeOH presentaron niveles signifi cativosde actividad antioxidante, con valores de RC50 de 6,8 x 10-2 y 4,7 x 10-2 mg/mL, respectivamente. Ninguno de losextractos presentó una toxicidad general signifi cativa (LD50 = >1000 mg/mL). Se observó que los tres principalescomponentes bioactivos del extracto de MeOH fueron los lignanos arctigenina, arctiina y matairesinosida. Lasestructuras de estos lignanos se dilucidaron mediante análisis espectroscópicos exhaustivos y comparación directacon los datos respectivos publicados. Éste es el primer informe sobre la ocurrencia de arctiina y matairesinol en C.dealbata. También se presenta la distribución de estos lignanos dentro del género Centaurea

Parity Doubling and the S Parameter Below the Conformal Window

We describe a lattice simulation of the masses and decay constants of the lowest-lying vector and axial resonances, and the electroweak S parameter, in an SU(3) gauge theory with $N_f = 2$ and 6 fermions in the fundamental representation. The spectrum becomes more parity doubled and the S parameter per electroweak doublet decreases when $N_f$ is increased from 2 to 6, motivating study of these trends as $N_f$ is increased further, toward the critical value for transition from confinement to infrared conformality.Comment: 4 pages, 5 figures; to be submitted to PR

The frequency of bowel and bladder problems in multiple sclerosis and its relation to fatigue: A single centre experience

Background Bowel and bladder problems affect more than 50% of people with Multiple Sclerosis (MS). These problems have a large impact on quality of life and place a significant burden on health systems. Objectives This study aimed to ascertain the frequency of bladder and bowel problems in a select Australian MS cohort and to investigate the relationships between level of disability, bladder and bowel problems, and fatigue. Methods Questionnaires on the nature and severity of MS symptoms were distributed to clients attending an Australian MS centre. Log-binomial regression and multiple linear regression models were used to investigate relationships between disability, fatigue, and bladder and bowel problems. Results and conclusions Of 167 questionnaires distributed, 136 were completed. Bladder problems were reported by 87 (74.4%) respondents, whilst 66 (48.9%) experienced functional constipation and 43 (31.9%) faecal incontinence. This frequency in our select Australian MS population is similar to that reported globally. There was a significant correlation between level of disability and: bladder problems (p = 0.015), faecal incontinence (p = 0.001), fatigue (p<0.001) and constipation (p = 0.016, relative risk: 1.16). Further investigation into the causal relationships between various MS symptoms may be beneficial in the development of novel therapeutic strategies for people with MS

Faint young Sun paradox remains

The Sun was fainter when the Earth was young, but the climate was generally at least as warm as today; this is known as the `faint young Sun paradox'. Rosing et al. [1] claim that the paradox can be resolved by making the early Earth's clouds and surface less reflective. We show that, even with the strongest plausible assumptions, reducing cloud and surface albedos falls short by a factor of two of resolving the paradox. A temperate Archean climate cannot be reconciled with the low level of CO2 suggested by Rosing et al. [1]; a stronger greenhouse effect is needed.Comment: 3 pages, no figures. In press in Nature. v2 corrects typo in author list in original submissio

Roles of TRPV1 and neuropeptidergic receptors in dorsal root reflex-mediated neurogenic inflammation induced by intradermal injection of capsaicin

<p>Abstract</p> <p>Background</p> <p>Acute cutaneous neurogenic inflammation initiated by activation of transient receptor potential vanilloid-1 (TRPV₁) receptors following intradermal injection of capsaicin is mediated mainly by dorsal root reflexes (DRRs). Inflammatory neuropeptides are suggested to be released from primary afferent nociceptors participating in inflammation. However, no direct evidence demonstrates that the release of inflammatory substances is due to the triggering of DRRs and how activation of TRPV₁receptors initiates neurogenic inflammation via triggering DRRs.</p> <p>Results</p> <p>Here we used pharmacological manipulations to analyze the roles of TRPV₁and neuropeptidergic receptors in the DRR-mediated neurogenic inflammation induced by intradermal injection of capsaicin. The degree of cutaneous inflammation in the hindpaw that followed capsaicin injection was assessed by measurements of local blood flow (vasodilation) and paw-thickness (edema) of the foot skin in anesthetized rats. Local injection of capsaicin, calcitonin gene-related peptide (CGRP) or substance P (SP) resulted in cutaneous vasodilation and edema. Removal of DRRs by either spinal dorsal rhizotomy or intrathecal administration of the GABA_Areceptor antagonist, bicuculline, reduced dramatically the capsaicin-induced vasodilation and edema. In contrast, CGRP- or SP-induced inflammation was not significantly affected after DRR removal. Dose-response analysis of the antagonistic effect of the TRPV₁receptor antagonist, capsazepine administered peripherally, shows that the capsaicin-evoked inflammation was inhibited in a dose-dependent manner, and nearly completely abolished by capsazepine at doses between 30–150 μg. In contrast, pretreatment of the periphery with different doses of CGRP_8–37(a CGRP receptor antagonist) or spantide I (a neurokinin 1 receptor antagonist) only reduced the inflammation. If both CGRP and NK₁receptors were blocked by co-administration of CGRP_8–37and spantide I, a stronger reduction in the capsaicin-initiated inflammation was produced.</p> <p>Conclusion</p> <p>Our data suggest that 1) the generation of DRRs is critical for driving the release of neuropeptides antidromically from primary afferent nociceptors; 2) activation of TRPV₁receptors in primary afferent nociceptors following intradermal capsaicin injection initiates this process; 3) the released CGRP and SP participate in neurogenic inflammation.</p

An Exact Fluctuating 1/2-BPS Configuration

This work explores the role of thermodynamic fluctuations in the two parameter giant and superstar configurations characterized by an ensemble of arbitrary liquid droplets or irregular shaped fuzzballs. Our analysis illustrates that the chemical and state-space geometric descriptions exhibit an intriguing set of exact pair correction functions and the global correlation lengths. The first principle of statistical mechanics shows that the possible canonical fluctuations may precisely be ascertained without any approximation. Interestingly, our intrinsic geometric study exemplifies that there exist exact fluctuating 1/2-BPS statistical configurations which involve an ensemble of microstates describing the liquid droplets or fuzzballs. The Gaussian fluctuations over an equilibrium chemical and state-space configurations accomplish a well-defined, non-degenerate, curved and regular intrinsic Riemannian manifolds for all physically admissible domains of black hole parameters. An explicit computation demonstrates that the underlying chemical correlations involve ordinary summations, whilst the state-space correlations may simply be depicted by standard polygamma functions. Our construction ascribes definite stability character to the canonical energy fluctuations and to the counting entropy associated with an arbitrary choice of excited boxes from an ensemble of ample boxes constituting a variety of Young tableaux.Comment: Minor changes, added references, 30 pages, 4 figures, PACS numbers: 04.70.-s: Physics of black holes; 04.70.-Bw: Classical black holes; 04.50.Gh Higher-dimensional black holes, black strings, and related objects; 04.60.Cf Gravitational aspects of string theory, accepted for publication in JHE

Holographic Construction of Excited CFT States

We present a systematic construction of bulk solutions that are dual to CFT excited states. The bulk solution is constructed perturbatively in bulk fields. The linearised solution is universal and depends only on the conformal dimension of the primary operator that is associated with the state via the operator-state correspondence, while higher order terms depend on detailed properties of the operator, such as its OPE with itself and generally involve many bulk fields. We illustrate the discussion with the holographic construction of the universal part of the solution for states of two dimensional CFTs, either on $R \times S^1$ or on $R^{1,1}$. We compute the 1-point function both in the CFT and in the bulk, finding exact agreement. We comment on the relation with other reconstruction approaches.Comment: 26 pages, 4 figures, v2: comments adde

Skyrmion fluctuations at a first-order phase transition boundary

Magnetic skyrmions are topologically protected spin textures with promising prospects for applications in data storage. They can form a lattice state due to competing magnetic interactions and are commonly found in a small region of the temperature - magnetic field phase diagram. Recent work has demonstrated that these magnetic quasi-particles fluctuate at the μeV energy scale. Here, we use a coherent x-ray correlation method at an x-ray free-electron laser to investigate these fluctuations in a magnetic phase coexistence region near a first-order transition boundary where fluctuations are not expected to play a major role. Surprisingly, we find that the relaxation of the intermediate scattering function at this transition differs significantly compared to that deep in the skyrmion lattice phase. The observation of a compressed exponential behavior suggests solid-like dynamics, often associated with jamming. We assign this behavior to disorder and the phase coexistence observed in a narrow field-window near the transition, which can cause fluctuations that lead to glassy behavior

Non-extremal Black Hole Microstates: Fuzzballs of Fire or Fuzzballs of Fuzz ?

We construct the first family of microstate geometries of near-extremal black holes, by placing metastable supertubes inside certain scaling supersymmetric smooth microstate geometries. These fuzzballs differ from the classical black hole solution macroscopically at the horizon scale, and for certain probes the fluctuations between various fuzzballs will be visible as thermal noise far away from the horizon. We discuss whether these fuzzballs appear to infalling observers as fuzzballs of fuzz or as fuzzballs of fire. The existence of these solutions suggests that the singularity of non-extremal black holes is resolved all the way to the outer horizon and this "backwards in time" singularity resolution can shed light on the resolution of spacelike cosmological singularities.Comment: 34 pages, 10 figure