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The magnetar SGR J1935+2154 underwent a new active episode on 2020 April 27–28, when a forest of hundreds of X-ray bursts and a large enhancement of the persistent flux were detected. For the first time, a radio burst with properties similar to those of fast radio bursts and with a X-ray counterpart was observed from this source, showing that magnetars can power at least a group of fast radio bursts. In this paper, we report on the X-ray spectral and timing properties of SGR J1935+2154 based on a long-term monitoring campaign with Chandra, XMM–Newton, NuSTAR, Swift, and NICER covering a time-span of ∼7 months since the outburst onset. The broad-band spectrum exhibited a non-thermal power-law component (Γ ∼ 1.2) extending up to ∼20–25 keV throughout the campaign and a blackbody component with temperature decreasing from ∼1.5 keV at the outburst peak to ∼0.45 keV in the following months. We found that the luminosity decay is well described by the sum of two exponential functions, reflecting the fast decay (∼1 d) at the early stage of the outburst followed by a slower decrease (∼30 d). The source reached quiescence about ∼80 d after the outburst onset, releasing an energy of ∼6 × 1040 erg during the outburst. We detected X-ray pulsations in the XMM–Newton data sets and derived an average spin-down rate of ∼3.5 × 10−11 s s−1 using the spin period measurements derived in this work and three values reported previously during the same active period. Moreover, we report on simultaneous radio observations performed with the Sardinia Radio Telescope. No evidence for periodic or single-pulse radio emission was found.

Swift J1818.0-1607 is a radio-loud magnetar with a spin period of 1.36 s and a dipolar magnetic field strength of B~3E14 G, which is very young compared to the Galactic pulsar population. We report here on the long-term X-ray monitoring campaign of this young magnetar using XMM-Newton, NuSTAR, and Swift from the activation of its first outburst in March 2020 until October 2021, as well as INTEGRAL upper limits on its hard X-ray emission. The 1-10 keV magnetar spectrum is well modeled by an absorbed blackbody with a temperature of kT_BB~1.1 keV, and apparent reduction in the radius of the emitting region from ~0.6 to ~0.2 km. We also confirm the bright diffuse X-ray emission around the source extending between ~50'' and ~110''. A timing analysis revealed large torque variability, with an average spin-down rate nudot~-2.3E-11 Hz^2 that appears to decrease in magnitude over time. We also observed Swift J1818.0-1607 with the Karl G. Jansky Very Large Array (VLA) on 2021 March 22. We detected the radio counterpart to Swift J1818.0-1607 measuring a flux density of S_v = 4.38+/-0.05 mJy at 3 GHz, and a half ring-like structure of bright diffuse radio emission located at ~90'' to the west of the magnetar. We tentatively suggest that the diffuse X-ray emission is due to a dust scattering halo and that the radio structure may be associated with the supernova remnant of this young pulsar, based on its morphology., 19 pages, 8 figures, accepted for publication on ApJ

The small intestine has a remarkable ability to enhance its absorptive and digestive surface area through the formation of villi, a process known as villification. We sought to learn whether developing mouse and human tissue-engineered small intestine (TESI) followed known developmental biology routes to villification, such as Sonic hedgehog (SHH)/Indian hedgehog (IHH) and bone morphogenetic protein 4 (BMP4)/forkhead box F1 (FOXF1) signaling to identify targets to enhance the development of TESI. After generating TESI from prenatal and postnatal stem cell sources, we evaluated the effect of cell source derivation on villification with a grading scheme to approximate developmental stage. χ2 analysis compared the prevalence of TESI grade from each stem cell source. RNAscope probes detected genes known to direct villification and the development of the crypt-villus axis in mouse and human development. These were compared in TESI derived from various pluripotent and progenitor cell donor cell types as well as native human fetal and postnatal tissues. Prenatal and pluripotent cell sources form mature villus and crypt-like structures more frequently than postnatal donor sources, and there are alternate routes to villus formation. Human TESI recapitulates epithelial to mesenchymal crosstalk of several genes identified in development, with fetal and pluripotent donor-derived TESI arriving at villus formation following described developmental patterns. However, postnatal TESI is much less likely to form complete villus-crypt patterns and demonstrates alternate SHH/IHH and BMP4/FOXF1 signaling patterns. Grading TESI and other cellular constructs may assist discoveries to support future human therapies.NEW & NOTEWORTHY The small intestine can enhance its absorptive and digestive surface area through a process known as villification. Tissue-engineered small intestine achieves mature villification at varying levels of success between differing sources. We have developed a consistent grading schema of morphology and characterized it across multiple developmental pathways, allowing objective comparison between differing constructs and sources.

We observed the periodic radio transient GLEAM-X J162759.5-523504.3 (GLEAM-X J1627) using the Chandra X-ray Observatory for about 30 ks on 2022 January 22–23, simultaneously with radio observations from the Murchison Widefield Array, MeerKAT, and the Australia Telescope Compact Array. Its radio emission and 18 min periodicity led the source to be tentatively interpreted as an extreme magnetar or a peculiar highly magnetic white dwarf. The source was not detected in the 0.3–8 keV energy range with a 3σ upper limit on the count rate of 3 × 10−4 counts s−1. No radio emission was detected during our X-ray observations either. Furthermore, we studied the field around GLEAM-X J1627 using archival European Southern Observatory and DECam Plane Survey data, as well as recent Southern African Large Telescope observations. Many sources are present close to the position of GLEAM-X J1627, but only two within the 2'' radio position uncertainty. Depending on the assumed spectral distribution, the upper limits converted to an X-ray luminosity of LX < 6.5 × 1029 erg s−1 for a blackbody with temperature kT = 0.3 keV, or LX < 9 × 1029 erg s−1 for a power law with photon index Γ = 2 (assuming a 1.3 kpc distance). Furthermore, we performed magneto-thermal simulations for neutron stars considering crust- and core-dominated field configurations. Based on our multiband limits, we conclude that (i) in the magnetar scenario, the X-ray upper limits suggest that GLEAM-X J1627 should be older than ∼1 Myr, unless it has a core-dominated magnetic field or has experienced fast cooling; (ii) in the white dwarf scenario, we can rule out most binary systems, a hot sub-dwarf, and a hot magnetic isolated white dwarf (T ≳ 10.000 K), while a cold isolated white dwarf is still compatible with our limits., N.R., F.C.Z., C.D., M.R., V.G., C.P., A.B., and E.P. are supported by the ERC Consolidator Grant "MAGNESIA" under grant agreement No. 817661, and National Spanish grant No. PGC2018-095512-BI00. F.C.Z., A.B., and V.G. are also supported by Juan de la Cierva Fellowships. C.D., M.R., and C.A.'s work has been carried out within the framework of the doctoral program in Physics of the Universitat Autónoma de Barcelona. N.H.W. is supported by an Australian Research Council Future Fellowship (project number FT190100231) funded by the Australian Government. D.d.M. acknowledges financial support from the Italian Space Agency (ASI) and National Institute for Astrophysics (INAF) under agreements ASI-INAF I/037/12/0 and ASI-INAF n.2017-14-H.0 and from INAF "Sostegno alla ricerca scientifica main streams dell'INAF," Presidential Decree 43/2018 and from INAF "SKA/CTA projects," Presidential Decree 70/2016. D.B. acknowledges support from the South African National Research Foundation. D.V. is supported by the ERC Starting Grant "IMAGINE" under grant agreement No. 948582. This work was also partially supported by the program Unidad de Excelencia Maria de Maetzu de Maeztu CEX2020-001058-M and by the PHAROS COST Action (grant No. CA16214).

Medical simulators have become an important tool for teaching and developing skills in health personnel. The present work describes the design and construction of a simulator for cardiopulmonary resuscitation in adults, of intermediate fidelity, equipped with monitoring software. This device has an adult-size torso, with sensors and actuators controlled and monitored wirelessly through the user’s computer. The prototype aims to assist in the training of paramedics and first responders, due to its ability to show real-time data on the execution of the cardiopulmonary resuscitation maneuver. The simulator has been designed in a modular way so that it allows an easy assembly and change of pieces if necessary. The graphical interface gives feedback in real time on the effectiveness of the maneuver. Based on surveys carried out in trained personnel, it was confirmed that the simulator is very useful to carry out practices for which it was designed, as well as to reduce the cost of implementation by being built with materials available in the local market.

To reduce overall design complexity and cost for RAM, a design paradigm is discussed that is based on a single silicon device containing multiple, configurable interfaces with a common RAM core. This will help bring to market more devices that operate in extreme environments. The cost per die is higher due to the addition of the configurable interface, but yields a net reduction in overall engineering development time for a given product family by a factor of four to five. To demonstrate this design paradigm a family of five RAM chips built on a single silicon design is developed. They are designed for low-power consumption and highly reliable, fault-tolerant operation, while operating over a temperature range of −55 to +300 degrees C.

This paper presents three new tools appropriate for content analysis of sports, applied to footage from snooker broadcasts in particular. The first tool is a new feature for parsing a sequence based on geometry without the need for deriving 3D information. The second tool allows events to be detected where an event is characterised by an object leaving the scene at a particular location. The final tool is a mechanism for summarising motion in a shot for use in a content-based summary. As a matter of course, the paper considers a number of enabling techniques such as the removal of irrelevant objects and object tracking using a particle filter. The paper shows that by exploiting context, a convincing summary can be made for snooker footage.

Mono-, di-, tri- and tetra-ruthenated porphyrins derived from phenyl/4-pyridyl mesosubstituted porphyrin and a trans di-ruthenated dipyridyl octaethylporphyrin have been synthesised. Coated on carbon electrodes, they have been tested as a sensor for sulfite using the oxidation wave of the Ru(II)/Ru(III) couples in hydroalcoholic solutions. At least two peripheral Ru are necessary to trigger the catalysis off. No major influence of the central metallic ions has been detected, but the Co (II) is coordinated by the sulfite.

Weed invasions are an increasing threat to the extensive wetlands of the Northern Territory's wet-dry tropics. Although the conservation value of these wetlands is in some ways undisputed, it is evident from the Government's multiple land use policy that it is also misunderstood. This policy aims to maximise economic returns from wetlands while protecting their ecological integrity at a time when ecological and economic costs associated with weeds are, at least in the short term, set to worsen. The underlying reasons behind wetland loss and degradation in Australia parallel those identified in Mediterranean Europe where there was antipathy from bureaucracies toward science and ecology. Several case studies from the Northern Territory explore how ecological, anthropogenic, political and economic factors contribute to weed problems. Caution is necessary when translating experience from agricultural weeds to environmental weeds. Managers have not always heeded the advice of specialists and practitioners, whose understanding of the ecological basis to weed invasions is not in as parlous a state as sometimes thought. Even when faced with sound information from which to manage, it was non-ecological reasons that slowed down or prevented effective weed control. If the floristic identity and diversity of Australia's natural wetlands is to be retained, then weeds need serious and immediate attention. Weed impacts progress beyond loss of wetland habitat and biodiversity to regional changes in landscape processes. We advocate that governments and industry recognise and address the underlying non-ecological reasons that exacerbate weed problems and set priorities to fund relevant practical studies and control programs that enable inventive weed management. Cooperation between land users, custodians and the wider community can help to overcome bureaucratic obstacles and enable judicious weed control that contributes effectively to wetland protection.

Wetland conservation and management in Australia is not supported by a comprehensive information base. A national inventory has not been compiled and we have very little information on the areal extent and loss of wetlands. Further, we have little information on the values and benefits (products, functions and attributes) derived from wetlands and how these have been degraded or lost. We do know, however, that in some areas at least, wetland loss and degradation has been severe and may even be still occurring. Much of the scientific attention to wetland management has been directed towards the apparent (or ecological) reasons for wetland loss and degradation – changes to the water regime, physical modification of the habitat, eutrophication and other pollution, and invasion by exotic pest species. Lists of threats to wetlands have been compiled, but these rarely address the non-ecological reasons that have resulted in so many wetlands being lost or degraded. In this paper we summarize the key points made from a number of case studies of Australian wetlands that highlight the non-ecological causes of wetland loss and degradation. From this analysis we conclude that awareness and understanding about the non-ecological causes of wetland loss and degradation need to be as well understood as the ecological causes. Foremost amongst these we highlight greater attention to the following issues: economic development in wetlands, bureaucratic obstacles, lack of information or poor access to information, and poor general awareness of the values and benefits derived from wetlands. We further conclude that wetland loss and degradation does not need to happen – our wetlands are valuable and already severely degraded. For this situation to be rectified we need to ensure that the knowledge and expertise of wetland scientists is heard and heeded by decision-makers and wetland users and owners.

The adverse impacts of weeds on natural ecosystems, together with the inadequate outcomes from treating weeds as a symptom, have escalated interest in finding efficacious control methods. With the aim of protecting wetlands from invasive weeds, this contribution uses the woody shrub Mimosa pigra L. (mimosa) as a case history to examine the methodology of classical biological control and the reasons for the widely accepted 75% failure rate. Overall objectives are for all biocontrol agents to have the opportunity to fully express their potential and to insure that limited resources are spent wisely on attainable weed control. The three main conclusions were that (1) the premises on which biocontrol is based has restricted advancement of this method; (2) monitoring is the logical first step to improving the selection of agents and release sites; and (3) it may be more cost-effective to introduce fewer agents that have undergone agent/plant and host/home range pre- and post-release ecological studies. Weed control may remain elusive unless advantage is taken of every beneficial result. Innovative assistance to agents and the integration of different control methods may preserve a role for weed biological control and has the potential to be of great importance for future weed management. It is proposed that the climate in the Top End of the Northern Territory and the lack of competition on the floodplains has contributed to mimosa's invasiveness. Climate may also underly the difficulties faced by agents. Agents appear unable to impart effective control in the dry season because of low numbers which relates to mimosa's poor growth; nor in the wet season, when the impact from high numbers of agents is outstripped by mimosa's growth.

Soft gamma-ray repeaters and anomalous X-ray pulsars are a small (but growing) group of X-ray sources characterized by the emission of short bursts and by a large variability in their persistent flux. They are believed to be magnetars, i.e. neutron stars powered by extreme magnetic fields 1E14-1E15 G). We found evidence for a magnetar with a low magnetic field, SGR 0418+5729, recently detected after it emitted bursts similar to those of soft gamma-ray repeaters. New X-ray observations show that its dipolar magnetic field cannot be greater than 8E12 G, well in the range of ordinary radio pulsars, implying that a high surface dipolar magnetic field is not necessarily required for magnetar-like activity. The magnetar population may thus include objects with a wider range of magnetic-field strengths, ages and evolutionary stages than observed so far., Comment: 4 pages, 2 figures; to appear in the Proceedings of the Pulsar Conference 2010, Chia, Sardinia (Italy), 10-15 October 2010

The High Time Resolution Universe survey for pulsars and fast transients has yielded the discovery of a slow radio pulsar, PSR J1622−4950, that despite its high dispersion measure exhibited a highly variable flux density and integrated pulse profile. The pulsar shares many properties with the two previously known magnetars that emit radio pulsations, including a similarly high inferred magnetic field strength. In contrast to other magnetars, PSR J1622−4950 shows no observed variations in X‐ray emission.

The Australian Square Kilometre Array Pathfinder (ASKAP) is a 36-element array with a 30-square-degree field of view being built at the proposed SKA site in Western Australia. We are conducting a Design Study for pulsar observations with ASKAP, planning both timing and search observations. We provide an overview of the ASKAP telescope and an update on pulsar-related progress., Comment: To appear in proceedings of "Radio Pulsars: An astrophysical key to unlock the secrets of the Universe"

Here we report on XMM‐Newton and Chandra observations that allowed us to measure the pulsation period and spin‐down rate of SGR 1627–41, the only known magnetar for which these key pieces of information were still missing.

SGR 0526-66 was the first soft gamma-ray repeater (SGR) from which a giant flare was detected in March 1979, suggesting the existence of magnetars, i.e. neutron stars powered by the decay of their extremely strong magnetic field. Since then, very little information has been obtained on this object, mainly because it has been burst-inactive since 1983 and the study of its persistent X-ray emission has been hampered by its large distance and its location in a X-ray bright supernova remnant in the Large Magellanic Cloud. Here we report on a comprehensive analysis of all the available XMM-Newton observations of SGR 0526-66. In particular, thanks to a deep observation taken in 2007, we measured its pulsation period (P = 8.0544 +/- 0.0002 s) 6 years after its latest detection by Chandra. This allowed us to detect for the first time a significant reduction of its spin-down rate. From a comparison with two shorter XMM-Newton observations performed in 2000 and 2001, we found no significant changes in the spectrum, which is well modelled by an absorbed power-law with nH = 4.6E+21 cm^-2 and photon index = 3.27. The high luminosity (about 4E+35 erg/s, in the 1-10 keV energy band) still observed about 25 years after the latest detection of bursting activity places SGR 0526-66 in the group of bright and persistent magnetar candidates., 5 pages, 3 figures (1 color) and 2 tables; Accepted for publication in MNRAS Letters

We present preliminary results on the spectral modeling of magnetars' X‐ray emission through a resonant cyclotron scattering model. We fit the soft and hard X‐ray spectrum of all magnetars with a main component representing a thermal emission from the neutron star surface which scatters (through a resonant cyclotron scattering process) on a slab of mildly relativistic magnetospheric electrons. Here we present the results obtained for the 0.5–200 keV (XMM–Newton+INTEGRAL) spectrum of the anomalous X‐ray pulsar 1E 1841–045, and the 0.5–10 keV (XMM–Newton) variable spectrum of the transient magnetar XTE J1810–197.

We present the XMM–Newton discovery of X‐ray pulsations and a ∼1 keV spectral feature from RRAT J1819–1458, a Rotating Radio Transient source with an inferred surface dipole magnetic field of 5×1013 G and a 4.26 s spin period. We detect pulsations at the period predicted by the radio ephemeris, providing an unambiguous identification with the radio source and confirmation of its neutron star nature. The X‐ray pulse has a 0.3–5 keV pulsed fraction of 34% and is aligned with the radio pulse. On the other hand, the X‐ray spectrum is well fit by an absorbed blackbody with kT = 0.14 keV with the addition of a broad absorption feature at 1 keV The nature of this absorption feature is still not settled, it might be due to atomic transitions in the atmosphere or to resonant proton cyclotron scattering. No evidence for any X‐ray bursts or aperiodic variability has been found.

In 2003 a previously unpulsed Einstein and ROSAT source cataloged as soft and dim (Lx of few 10^33 ergs) thermal emitting object, namely XTE J1810-197, was identified as the first unambiguous transient Anomalous X-ray Pulsar. Two years later this source was also found to be a bright highly polarized transient radio pulsar, a unique property among both AXPs and radio pulsars. In September 2006 the Swift Burst Alert Telescope (BAT) detected an intense burst from the candidate AXP CXOU J164710.2-455216, which entered in an outburst state reaching a peak emission of at least a factor of 300 higher than quiescence. Here, we briefly outline the recent results concerning the outburst phenomena observed in these two AXPs. In particular, XTE J1810-197 has probed to be a unique laboratory to monitor the timing and spectral properties of a cooling/fading AXP, while new important information have been inferred from X-ray and radio band simultaneous observations. CXOU J164710.2-455216 has been monitored in X-rays and radio bands since the very beginning of its outbursting state allowing us to cover the first phases of the outburst and to study the timing and spectral behavior during the first months., 5 pages, 3 figures, proceedings of the conference "40 Years of Pulsars, Millisecond Pulsars, Magnetars and More", Montreal, August 12-17 2007. To be published by AIPC

The soft gamma-ray repeater SGR 1806-20 has been attracting a lot of attention owing to the fact that in December 2004 it emitted the most powerful giant flare ever observed. Here we present the results of the first Suzaku observation of SGR 1806-20, that seems to have reached a state characterized by a flux close to the pre-flare level and by a relatively soft spectrum. Despite this, the source remained quite active, as testified by several short bursts observed by Suzaku. We discuss the broadband spectral properties of SGR 1806-20 in the context of the magnetar model, considering its recent theoretical developments., 3 pages, 1 figure. Proceedings of the conference "40 Years of Pulsars, Millisecond Pulsars, Magnetars and More", Montreal, August 12-17 2007. AIP, in press

Magnetar's persistent emission above 10 keV was recently discovered thanks to the imaging capabilities of the IBIS coded mask telescope on board the INTEGRAL satellite. The only two sources that show some degree of long term variability are SGR 1806-20 and 1RXS J170849.0-400910. We find some indications that variability of these hard tails could be the driver of the spectral variability measured in these sources below 10 keV. In addition we report for the first time the detection at 2.8 sigma level of pulsations in the hard X-ray tail of SGR 1806-20., 3 pages, 3 figures, proceedings of the conference "40 Years of Pulsars, Millisecond Pulsars, Magnetars and More", Montreal, August 12-17 2007. To be published by AIPC

In this paper, we propose a multimodal approach to illicit content detection in videos. Distribution of pornographic material over computer networks has been taking place since the inception of the internet. Until recently, most of the research focuses on illicit content detection in images and text. Typically it involves robust skin detection, texture characterisation, shape modelling and keyword filtering. Video however provides the opportunity of exploiting supplementary features including audio and motion for additional confidence in the classification process. This work investigates the use of visual motion information and periodicity in the audio stream for illicit content detection in videos.

This paper presents a robust method to estimate the unknown standard deviation of a centred normal distribution from a mixture density. This method is applied to different signal processing problems. The first one concerns silence segmentation from audio data. The second application deals with colour class parameter extraction. In this later case, the mean is also estimated from the observations.

This paper investigates the semantic analysis of broadcast tennis footage. We consider the spatio-temporal behaviour of an object in the footage as being the embodiment of a semantic event. This object is tracked using a colour based particle filter. The video syntax and audio features are used to help delineate the temporal boundaries of these events. For broadcast tennis footage, the system firstly parses the video sequence based on the geometry of the content in view and classifies the clip as a particular view type. The temporal behaviour of the serving player is modelled using a HMM. As a result, each model is representative of a particular semantic episode. Events are then summarised using a number of synthesised keyframes.

In this paper, we investigate the retrieval of dynamic events that occur in broadcast sports footage. Dynamic events in sports are important in so far as they are related to the game semantics. Thus far, the temporal interleaving of camera views has been used to infer these types of events. We propose the use of the spatio-temporal behaviour of an object in the footage as an embodiment of a semantic event. This is accomplished by modeling the evolution of the position of the object with a hidden Markov model (HMM). Snooker is used as an example for the purpose of this research. The system firstly parses the video sequence based on the geometry of the content in the camera view and classifies the footage as a particular view type. Secondly, we consider the relative position of the white ball on the snooker table over the duration of a clip to embody semantic events. A colour based particle filter is employed to robustly track the snooker balls. The temporal behaviour of the white ball is modeled using a HMM where each model is representative of a particular semantic episode. Upon collision of the white ball with another coloured ball, a separate track is instantiated.

In this paper we investigate the retrieval of semantic events that occur in broadcast sports footage. We do so by considering the spatio-temporal behaviour of an object in the footage as being the embodiment of a particular semantic event. Broadcast snooker footage is used as an example of the sports footage for the purpose of this research. The system parses the sports video using the geometry of the content in view and classifies the footage as a particular view type. A colour based particle filter is then employed to robustly track the snooker balls, in the appropriate view, to evoke the semantics of the event. Over the duration of a player shot, the position of the white ball on the snooker table is used to model the high level semantic structure occurring in the footage. Upon collision of the white ball with another coloured ball, a separate track is instantiated allowing for the detection of pots and fouls, providing additional clues to the event in progress.

In recent years, there has been increasing work in the area of content retrieval for sports. The idea is generally to extract important events or create summaries to allow personalisation of the media stream. While previous work in sports analysis has employed either the audio or video stream to achieve some goal, there is little work that explores how much can be achieved by combining the two streams. This paper combines both audio and image features to identify the key episode in tennis broadcasts. The image feature is based on image moments and is able to capture the essence of scene geometry without recourse to 3D modelling. The audio feature uses PCA to identify the sound of the ball hitting the racket. The features are modelled as stochastic processes and the work combines the features using a likelihood approach. The results show that combining the features yields a much more robust system than using the features separately.

This paper considers the statistics of local appearance based measures that are suitable for the visual parsing of sport events. The moments of the colour information are computed, and the shape content in the frames is characterised by the moments of local shape measures. Their generation process is very low cost. The temporal evolution of the features then is modelled with a Hidden Markov Model. The HMM is used to generate higher level information by classifying the shots as close ups, court views, crowd shots and so on. The paper illustrates how those simple features, coupled with the HMM, can be used for parsing snooker and tennis footages.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper presents the tools in a system for creating a semantically meaningful summary of broadcast Snooker footage. The system parses the sequence, identifies relevant camera views and tracks ball movement. Two new algorithms for video retrieval are presented. The first is the use of the 2nd order moment of the Hough Transform of the image for sequence parsing. The second method is the use of enclosed regions for detecting the disappearance of objects. The moment feature captures the geometry of the scene without extracting the 3D scene geometry. It is expected that this new feature is applicable to most sports in which a playing area is delineated by field lines.

We studied a group of 36 fertile women affected with moderate-to-severe cyclical mastalgia (mean age: 26.0 years) showing a normal menstrual history and normal basal levels of circulating hormones, including prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E2), progesterone (P), testosterone (T), dehydroepiandrosterone sulphate (delta HEAs), androstenedione (A). Using serial measurements of PRL plasma levels after an intravenous injection of thyrotropin-releasing hormone (TRH), (TRH test), patients were divided in two groups: 19 patients with abnormal PRL response to TRH and the remaining 17 with normal response.Bromocriptine treatment, 2.5 mg b.i.d. for 3-6 months, was effective in 73.6% of patients with abnormal TRH test and in 23.5% of patients with normal TRH test: the difference was statistically significant. On the other hand, 76.9% of patients with either normal TRH test or resistant to bromocriptine therapy had a favourable response to percutaneous progesterone and systemic non-steroidal antiinflammatory drugs (NSAIDs).These results seem to confirm the hypothesis that PRL response to TRH could be used to identify patients affected with cyclical mastalgia that are likely to benefit by bromocriptine treatment.

Warthin's tumor is a debated pathological condition. There are many controversies concerning this disease such as its origin (hereditary or acquired), its nature (whether neoplastic or no), its topographical relation with the salivary glands, its relationship with possible concomitant pathologies (dysmetabolic, infective, neoplastic, etc.), the problems of diagnosis and of differential diagnosis with all possible causes of cervical swelling, and also the problems of surgical treatment in relation to the possible involvement of the salivary glands. In this paper two clinical cases are described. The first one is characterized by a latero-cervical bilateral Warthin's tumor, apparently independent of the salivary glands, associated with rhinopharyngeal lymphatic hyperplasia and nodular colloid goiter. The second case is characterized by a latero-cervical uni-lateral Warthin's tumor, linked by a slender layer with the ipsilateral parotid gland, associated with breast cancer. Starting point from the discussion of these two cases, the Authors make remarks in order to answer some of the aforementioned questions.

A recent series of papers by Gifford and Longsworth [1–3] describe a simple refrigeration device (illustrated schematically in Fig. 1) which has potential applications. They have called this device a “pulse tube refrigerator.” The pulse tube refrigerator consists of a regenerator connected in series with an open tube, which is the pulse tube. The void volume of the regenerator is V R and the void volume of the pulse tube is V pt . Gas enters and leaves the device through the warm end of the regenerator which is at a temperature T W . The volume V h , which is connected to the end of the pulse tube, is maintained at a temperature T h by means of cooling medium. In general, at least for the simple pulse tube, both T h and T W will be approximately at room temperature.

The reproductive characteristics of T. procerum in three lagoons in the Mediterranean south-east of South Australia were used to investigate the role of water regime in the often heterogeneous and patchy distribution of aquatic vegetation. A theoretical explanation for these patterns, based on sexual reproduction vis-a-vis seedling establishment, is proposed. Owing to the unpredictable nature of seed dispersal and the narrow range of suitable conditions for germination and establishment that result from fluctuating and variable water levels, establishment events are spatially and temporally dynamic. These features may be important for maintaining species distribution, species survival and habitat diversity. Population resilience through genetically heterogeneous stands is another outcome. The implications of sexual reproduction by clonal plants are discussed, as is the need to maintain the conditions that plants need to flower, germinate and become established. The unpredictable nature of establishment events makes them difficult to manage. Regulation and pondageldrainage may be having a profound effect on the survival of many aquatic plant species owing to their inability to regenerate under such conditions.

The response of B. arthrophylla and T. procerum in pot experiments to depth and depth changes provided insight into how plants survive fluctuating water levels. At 0 cm depth, most biomass was placed below ground, which can be interpreted as the placement of resource-acquiring tissues (roots, rhizomes) in resource (nutrients, space) -supplying environments. At 50 and 100 cm, the placement of biomass into shoots recognized the need for a higher supply of above-ground resources (light, inorganic carbon, oxygen). However, the responses of the two species to flooding or exposure differed. Rhizome storage supported an increase in the number and height of B. arthrophylla stems when flooded by 50 cm but this species was unable to counteract submergence to 100 cm without the critical loss of root mass. The slow turnover rate of the cuticularized B. arthrophylla stems indicates that biomass needs to be allocated above water as well as above ground. Other responses indicated that this species may be better suited to seasonally fluctuating rather than permanent water levels. T. procerum dealt with water level changes via morphological plasticity. Along with the rapid growth and turnover of the spongy leaves, its shoot and total mass were maintained primarily from resources in the tubers.

A community survey of skin disease was carried out in Lambeth, London. A postal questionnaire asking recipients to give details of the presence of skin disease was sent to a stratified sample of 2180 adults; a subsample of 614 persons were interviewed at home and an inspection was made of the exposed parts of their skin. Altogether 92 conditions were identified. These were graded for clinical severity and classified into 13 groups. The overall prevalence of skin disease thought to justify medical care was 22-5%. The most common important condition was eczema with a prevalence of 6-1%. Age, sex, and social class trends in prevalence were found in certain groups of skin disease. Of those with a skin disease thought to justify medical care, only 21% reported having attended their general practitioner in the past six months for a skin complaint. The reported use of medical care and self medication is discussed in relation to the presence of skin disease and other factors.

A detailed thermal model of the Czochralski silicon process was developed to predict maximum crystal pull rates as a function of crystal size and various puller parameters. Experimental data are presened which confirm the model validity. Extrapolations of the model are shown to provide guidance for possible tradeoffs in equipment design or operational mode.