"Hiccup" accretion in the swinging pulsar IGR J18245-2452

IGR J18245-2452 is the fifteenth discovered accreting millisecond X-ray pulsar and the first source of this class showing direct evidence for transition between accretion and rotational powered emission states. These swing provided the strongest confirmation of the pulsar recycling scenario available so far. During the two XMM-Newton observations that were carried out while the source was in outburst in April 2013, IGR J18245-2452 displayed a unique and peculiar variability of its X-ray emission. In this work, we report on a detailed analysis of the XMM- Newton data and focus in particular on the timing and spectral variability of the source. IGR J18245-2452 continuously switches between lower and higher intensity states, with typical variations in flux up to a factor of about 500 in time scales as short as few seconds. These variations in the source intensity are sometimes associated to a dramatic spectral hardening, during which the power-law photon index of the source changes from Gamma=1.7 to Gamma=0.9. The pulse profiles extracted at different count rates and energies show a complex variability. These phenomena are not usually observed in accreting millisecond X-ray pulsars, at least not on such a short time scale. Fast variability was also found in the ATCA radio observations carried out for about 6 hours during the outburst at a frequency of 5.5 and 9 GHz. We interpret the variability observed from IGR J18245-2452 in terms of a "hiccup" accretion phase, during which the accretion of material from the inner boundary of the Keplerian disk is reduced by the onset of centrifugal inhibition of accretion, possibly causing the launch of strong outflows. Changes across accretion and propeller regimes have been long predicted and reproduced by MHD simulations of accreting millisecond X-ray pulsars but never observed to produce an extreme variability as that shown by IGR J18245-2452.Comment: A&A in press. Revised versio

Cosmological constant: relaxation vs multiverse

We consider a scalar field with a bottom-less potential, such as $g^3 \phi$, finding that cosmologies unavoidably end up with a crunch, late enough to be compatible with observations if $g \lesssim 1.2 H_0^{2/3} M_{\rm Pl}^{1/3}$. If rebounces avoid singularities, the multiverse acquires new features; in particular probabilities avoid some of the usual ambiguities. If rebounces change the vacuum energy by a small enough amount, this dynamics selects a small vacuum energy and becomes the most likely source of universes with anthropically small cosmological constant. Its probability distribution could avoid the gap by 2 orders of magnitude that seems left by standard anthropic selection.Comment: 15 pages, 3 figures; published versio

Proximate factors underpinning receiver responses to deceptive false alarm calls in wild tufted capuchin monkeys: is it counterdeception?

Previous research demonstrates that tufted capuchin monkeys use terrestrial predator alarm calls in a functionally deceptive manner to distract conspecifics when feeding on contestable resources, although the success of this tactic is limited because listeners frequently ignore these calls when given in such situations. While this decreased response rate is suggestive of a counterstrategy to deception by receivers, the proximate factors underpinning the behavior are unclear. The current study aims to test if the decreased response rate to alarm calls in competitive contexts is better explained by the perception of subtle acoustic differences between predator-elicited and deceptive false alarms, or by receivers varying their responses based on the context in which the signal is received. This was tested by first examining the acoustic structure of predator-elicited and deceptive false alarms for any potentially perceptible acoustic differences, and second by comparing the responses of capuchins to playbacks of each of predator-elicited and false alarms, played back in noncompetitive contexts. The results indicate that deceptive false alarms and predator-elicited alarms show, at best, minimal acoustic differences based on the structural features measured. Likewise, playbacks of deceptive false alarms elicited antipredator reactions at the same rate as did predator-elicited alarms, although there was a nonsignificant tendency for false alarms to be more likely to elicit escape reactions. The lack of robust acoustic differences together with the high response rate to false alarms in noncompetitive contexts suggests that the context in which the signal is received best explains receiver responses. It remains unclear, however, if listeners ascribe different meanings to the calls based on context, or if they generally ignore all signals in competitive contexts. Whether or not the decreased response rate of receivers directly stems from the deceptive use of the calls cannot be determined until these latter possibilities are rigorously tested

Relationship of some risk factors and symptoms in patients with acute coronary syndrome

Acute coronary syndrome (ACS) is one of the major causes of death in the worldwide. Clinical manifestations are different. So it's necessary to have knowledge about the types of symptoms experienced by patients with ACS. This study was performed to assay the Relationship of some risk factors and symptoms in patients with acute coronary syndrome. This cross-sectional study, were studied 294 patients with acute coronary syndrome at least 24 hours after admission had survived. Data was collected by a questionnaire that included demographic data form and check list of some symptoms and history of risk factors. There was a significant relationship between STEMI with vomiting (OR=1.94) and anxiety (OR=1.83) and UA with vomiting (OR=0.42). Between sex with weakness (OR=2.29) and anxiety (OR=1.82), diabetes with dyspenea (OR=1.8), weakness (OR=1.02) and tinnitus (OR=2.06) and hyperlipidemia with weakness (OR=2.35) and tinnitus (OR=2.49) was available significant difference. The findings of this study indicate that the appearance of symptoms of acute coronary syndrome were different as for ECG changes and risk factors, and more focused on those symptoms that they are common with any other diseases. Since, many of the symptoms of acute coronary syndrome can be potentially dangerous and life threatening, accurate diagnosis and timely action is crucial for the patients

The Pond

A collection of creative texts written concurrently with the creation of the artist’s thesis exhibition. A range of written forms coexist - poetry, prose, and dialogue - to open up the narrative and emotional space of the visual work. The text emerges from the point-of-view of different voices, describing experiences and body states that hinge upon the physical and conceptual space of the pond. Amphibiousness offers a gateway to a state of becoming and transformation. Some of the following texts appear in video works by the artist

Do Hiccups Echo? Late Holocene Interaction and Ceramic Production in Southern Papua New Guinea

The last five decades of research into Papua New Guinean archaeology have revealed a variety of rapid late Holocene cultural changes. The Ceramic Hiccup (c. 1200 – 800 years b.p.) is a little understood period of change along the south Papuan coast. It presents itself at the terminus of the Early Papuan Pottery (EPP) tradition as a rapid change in ceramic styles, lithic exchange, and settlement patterns. Previous interpretations have invoked causal factors such as migration, environment, and conflict. This article investigates this period of change by examining exchange and mobility patterns during EPP, through the Ceramic Hiccup, and into the ensuing traditions. Physico-chemical analysis (scanning electron microscopy, SEM) of 39 potsherds was conducted to understand changes in ceramic production during this period at two key sites, Taurama (AGN and AJA) and Eriama 1 (ACV), in the Port Moresby region of the south coast of Papua New Guinea. Although our interpretations are provisional due to a small sample size, it is argued here that, following the highly interactive period of EPP, a migration of ceramic manufacturing groups from the west supplants the local tradition (EPP) during the Ceramic Hiccup. There is a decline in interaction between ceramic communities toward the latter stages of EPP, with increased isolation and standardization of ceramics. This decline of interaction in the region is associated with a decline in chemical variability in ceramic components. The Ceramic Hiccup is representative of introduced ceramics, increased interaction and mobility

The Hiccup: a dynamical coupling process during the autumn transition in the Northern Hemisphere – similarities and differences to sudden stratospheric warmings

Sudden stratospheric warmings (SSWs) are the most prominent vertical coupling process in the middle atmosphere, which occur during winter and are caused by the interaction of planetary waves (PWs) with the zonal mean flow. Vertical coupling has also been identified during the equinox transitions, and is similarly associated with PWs. We argue that there is a characteristic aspect of the autumn transition in northern high latitudes, which we call the "hiccup", and which acts like a "mini SSW", i.e. like a small minor warming. We study the average characteristics of the hiccup based on a superimposed epoch analysis using a nudged version of the Canadian Middle Atmosphere Model, representing 30 years of historical data. Hiccups can be identified in about half the years studied. The mesospheric zonal wind results are compared to radar observations over Andenes (69° N, 16° E) for the years 2000–2013. A comparison of the average characteristics of hiccups and SSWs shows both similarities and differences between the two vertical coupling processes

The effect of gabapentin and pregabalin on symptoms other than pain and seizures. A review of the evidence

Gabapentin and pregabalin are drugs that act through reduction of the central sensitization. They are useful in conditions such as partial seizures and neuropathic pain. However, in the last decade these drugs appear to have been effective against a variety of other symptoms, such as pruritus, hot flushes in post-menopausal women and intractable hiccups. The drugs are probably also effective for many other symptoms related to central sensitization but the paucity of data does not allow for support of these claims. Both gabapentin and pregabalin have a good safety record.Gabapentin and pregabalin are drugs that act through reduction of the central sensitization. They are useful in conditions such as partial seizures and neuropathic pain. However, in the last decade these drugs appear to have been effective against a variety of other symptoms, such as pruritus, hot flushes in post-menopausal women and intractable hiccups. The drugs are probably also effective for many other symptoms related to central sensitization but the paucity of data does not allow for support of these claims. Both gabapentin and pregabalin have a good safety record

Violent Hiccups: An Infrequent Cause of Bradyarrhythmias

A hiccup, or singultus, results from a sudden, simultaneous, vigorous contraction of the diaphragm and inspiratory muscles, accompanied by closure of the glottis. Hiccups can be associated with bradyarrhythmias. The mechanism of this phenomenon is likely hiccup-induced Valsalva maneuver and increased parasympathetic tone. We present a case of a patient with violent hiccups producing a bradyarrhythmia