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Since their discovery in 1927, the phylogenetic status of the Myanmar amphipithecines has been highly debated. These fossil primates are recognized either as anthropoids or as adapiform strepsirrhines. This uncertainty was largely the consequence of a limited fossil record consisting mostly of jaw fragments but lacking the critical cranial elements that might resolve this debate. We report here cranial remains associated with an ulna from a single individual pertaining to the amphipithecine Ganlea megacanina. In addition to anthropoid-like dentognathic characters, Ganlea displays several ulna and skull features that testify to its anthropoid affinities (e.g. short subvertically oriented lacrimal duct, lacrimal foramen and bone inside the orbit, maxillary contribution to the lower orbital rim, fused metopic suture). By contrast to crown anthropoids, however, Ganlea lacks postorbital closure, confirming that postorbital closure appeared later than many anthropoid dentognathic characters and evolved convergently in extant tarsiers and anthropoids. Thus, amphipithecines must now be recognized as stem anthropoids offering a unique window on the early evolution of cranial and skeletal features in anthropoids and reinforcing the hypothesis of an origin and early diversification of anthropoids in Asia.

JEM-EUSO is a space science mission to explore the extreme energies and physics of the Universe. Its instrument will watch the darkside of the earth and will detect UV photons emitted from the extensive air shower caused by an ultra-high energy cosmic ray (UHECR above 1018 eV), or an extremely high energy cosmic ray (EHECR) particle (e.g. above about 1020 eV). Such a high-rigidity particle as the latter arrives almost in a straight line from its origin through the magnetic fields of our Milky Way Galaxy and is expected to allow us to trace the source location by its arrival direction. This can open the door to new astronomy with charged particles. In its 5 years of operation including the tilted mode, Extreme Universe Space Observatory an Japanese Experiment Module (JEM-EUSO) will detect at least 1000 events with E > 7 × 1019 eV with the Greisen–Zatsepin–Ku’zmin (GZK) suppression spectrum. It can determine the energy spectrum and source locations of GZK to super-GZK regions with a statistical accuracy of several percent. JEM-EUSO is planned to be deployed by H2 transfer vehicle (HTV) and will be attached to the Japanese Experiment Module/Exposure Facility (JEM/EF) of International Space Station. JAXA has selected JEM-EUSO as one of the mission candidates of the second phase utilization of JEM/EF for launch in the early-to-mid 2010 s.

Un nouvel ecureuil volant fossile, Belomys thamkaewi n. sp., est decrit, date de la fin du Pleistocene moyen jusqu'au Pleistocene terminal de Thailande. Il n'est connu que d'un gisement fossile, Crystal Cave, province de Kanchanabury, Thailande occidentale. Il differe surtout par sa tres grande taille des Belomys pearsonii actuels et pleistocenes. Le B. pearsonii actuel etait largement reparti en Thailande au cours du Pleistocene moyen, les limites de sa repartition etant largement etendues vers le sud au-dela de l'actuel isthme de Kra. La nouvelle espece, B. thamkaewi peut representer un descendant de grande taille de ces populations Thai du Pleistocene moyen de B. pearsonii, ou appartenir a une lignee differente d'un Belomys de grande taille. Les deux especes n'ont jamais ete trouvees sympatriques dans un meme gisement.

Charophyte gyrogonites from two Miocene sites in northern Thailand are studied and compared for population variation. Morphometrical differences between the two populations, determined as Nitellopsis merianii and N. meriani globula, correspond to variation at the interpopulation level and do not justify the distinction of two separate species as made by previous authors. The first exhaustive synonymy for both taxa is listed. Morphological differences can be attributed to environmental differences as reflected by distinct lithologies of the samples concerned. The eurasian character of N. merianii is underlined through its biogeographical distribution in China. The flora is in accordance with the early Middle Miocene age (16–14 My) previously published for vertebrate faunas from the same sites.

Only few data from South-East Asia document paleoenvironments evolution during the Cenozoic. Here we analyse palynological records from four sites of Thailand. The unique site dated from the Oligocene shows a temperate signal, while younger Miocene records show a tropical signal with variations in the hydrology of the deposition basin, as well as a temperate extra-local signal that could be related to a mid-altitude flora. The mid-Miocene Chiang Muan basin has delivered several occurrences of an opened biotope (Poaceae) alternatively replaced by what could be Syzygium gallery-forests. Khorat (−9 to −6.5 Ma) pollen records deliver similar results, but linked to a strong local signal. Regional and local signals remain difficult to separate, notably because of badly known palynomorphs, but our high resolution record confirm oceanic data that suggest high variability in Miocene climate, as well as modelling studies inferring an early onset of the Asian monsoon.

International audience

ISBN: 978-0-07354-0662-9; International audience; The Simbol-X telescope will be constitued by two satellites in formation flight. One will host the mirror module and the other the detector payload. This payload will be built with two main detectors able to measure the position, energy and arrival time of each focused photon, between 0.5 and 80 keV. The high sensitivity required by Simbol-X will necessitate low noise background detectors. To achieve this goal, those detectors will be surrounded by a passive graded shield, aimed to stop the out of field of view photons, and an active anticoïncidence system to tag the passing particles. This anticoïncidence detector, whose conception, optimisation and realization are under responsibility of the APC Laboratory, Paris, is based on plastic scintillator plates associated to multi-anodes photo-multipliers via optical fibers. In this paper, we will present the present status of the anticoïncidence system and its expected performances.

The Pierre Auger Observatory is a``hybrid'' UHECR detector. The surface detector (SD) and air fluorescence detector (FD) of the observatory are designed for observation of cosmic ray showers in coincidence, with a 10% duty cycle. The resulting data are expected to be superior in quality to those of either the SD or FD operating individually. Hybrid operation, triggering, data acquisition, and event reconstruction were successfully demonstrated during the prototype phase of the project. This paper focuses on 75 hybrid events recorded during a four month period of running with the prototype detectors in late 2001 and early 2002. The geometric technique for reconstruction of the hybrid events is described and its advantages over the traditional FD-only method are demonstrated. A lateral distribution for the water Cherenkov signals, derived from these data, is presented., Comment: Talk given at 28th International Cosmic Ray Conferences (ICRC 2003), Tsukuba, Japan, 31 Jul - 7 Aug 2003

A well preserved mouse skull has been recovered from a pedogenically modified mudstone layer (c. 2 millions years (MY) old) of Pinjor Formation (Upper Siwaliks) exposed east of Chandigarh, India. Comparison of the present skull with those of the extant species of the subgenus Mus reveals its closer relationship towards the house mouse Mus musculus lineage. The present fossil evidence is very much in line with the molecular, allozymic and ecological proposals for the time and place of origin of the subgenus Mus.

The SPIROC chip is a dedicated very front-end electronics for an ILC (International Linear Collider) prototype of hadronic calorimeter using Silicon photomultiplier (SiPM) or Multi-Pixel Photon Counters (MPPC) readout. This ASIC is due to equip a 10,000-channel demonstrator in 2010. SPIROC is an evolution of FLC-SiPM used for the ILC Analogue HCAL physics prototype. The first prototype of SPIROC was submitted in June 2007. It embeds cutting edge features that fulfil ILC final detector requirements. It has been realized in 0.35 ?m SiGe technology. It has been developed to match the requirements of large dynamic range, low noise, low consumption, high precision and large number of readout channels needed. SPIROC is an auto-triggered, dual gain, 36-channel ASIC which allows to measure on each channel the charge from one photoelectron to 2,000 photoelectron and the time with a 100 ps accurate Time-to-digital Converter (TDC). An analogue memory array with a depth of 16 for each channel is used to store the time information and the charge measurement. A 12-bit Wilkinson Analogue-to-digital Converter (ADC) has been embedded to digitize the analogue memory content (time and charge on 2 gains). The data are then stored in a 4 Kbytes RAM. A very complex digital part has been integrated to manage all these features and to transfer the data to the DAQ which is described in Dulucq et al. After an exhaustive description, the extensive measurement results of this new front-end chip are presented.

Physostigmine, as a pretreatment candidate for nerve agent poisoning, was examined for cardiopulmonary side effects. Cardiovascular and pulmonary parameters were monitored in unanesthetized domestic pigs which received pulmonary arterial infusion of 5 micrograms/kg/min physostigmine salicylate for 2 hr. A level of 74% inhibition of red blood cell (RBC) acetylcholinesterase (AChE) activity was attained in 45 min, and this level of carbamylation increased only slightly during the remaining infusion period. In addition to this large change in AChE activity, minor changes were observed in hematocrit, heart rate, body temperature, mean aortic pressure, pulmonary arterial wedge pressure, and pulmonary artery pressure. Typically, these parameters showed a trend toward elevated levels. Blood gases, pH, respiratory rate, tidal and minute volume, cardiac output, nonelastic resistance, and dynamic compliance were not significantly different from baseline values. The unanesthetized pig responds to physostigmine in a manner similar to that reported for other species and appears to be a suitable model for evaluating cardiopulmonary effects of cholinesterase inhibitors.

We measured the temperature in the rectum and two esophageal sites (retrocardiac and retrotracheal) during exercise in eight asthmatic and six normal subjects while they breathed air at subfreezing, ambient, and body conditions. Various aspects of pulmonary mechanics were recorded before and after exercise. The asthmatic subjects developed the greatest airway obstruction following exercise with cold air and no response at body conditions. There were no changes in pulmonary mechanics in the postexercise period in the normal individuals with any of the inspired air conditions. Despite these divergent mechanical responses retrotracheal temperatures fell by the same magnitude below core values in both groups of subjects, indicating that identical degrees of airway cooling occurred. We conclude that rather than having a defect in the ability to condition inspired air, asthmatic subjects are more responsive to the effects of incompletely conditioned air.

We examined the degree of airway obstruction that developed in eight asthmatics who exercised while breathing air under four conditions: (a) ambient room temperature and water content; (b) body temperature and ambient water content; (c) ambient room temperature fully saturated; and (d) body temperature fully saturated. These test conditions were performed in random order. Multiple aspects of pulmonary mechanics were measured before and 5 min after exercise. When air at ambient conditions was inhaled, the expected airway obstruction developed after exercise, and all variables changes significantly from their pre-challenge values. Heating the air to body temperature did not influence this response. Increasing the humidity at ambient temperatures significantly blunted the response, and by inhaling body temperature, fully saturated air completely prevented it from occurring. Thus, the water content of inspired air is an important variable in the development of exercise induced asthma.

The best mammalian fossil record during the Neogene of Western Europe is that of the rodents, the most successful and diversified mammal order. The study of origination and extinction during the Neogene (24-3 Ma BP) in one of the best documented areas, Spain and southern France, gives an insight into the dynamics of these communities and indicates the possible nature of the driving forces. Three main periods of time show a high rate of origination: the late Burdigalian (17.5 Ma BP), the early Vallesian (11.5-11 Ma BP) and the early Pliocene (4.2- 3.8 Ma BP). Two of these high origination-rate periods are immediately followed by important extinction events during which all cohorts are deeply affected (11.5-11 Ma BP and 4.2- 3.8 Ma BP). The most important extinction event seems to occur during the early Vallesian (11.5-11 Ma BP), which probably includes the middle/late Miocene boundary. At the Miocene/Pliocene boundary, and during the early Pliocene, the faunal turnover seems to become faster, inducing a strong decrease of the mean species duration. Whereas the main immigration event, which occurs at 17.5 Ma BP, can be related to other faunal migrations in terms of the closure of the Tethys, as it occurs also in eastern Africa and in southwest Asia, the middle/late Miocene boundary event may have been related to a period of ice growth in the Southern Hemisphere. The extinction event that affects the planktonic foraminifera at 12 Ma BP cannot be chronologically correlated to this southwestern European land-mammal extinction event, because the calibration of the marine fossil record during that time-span has to be precise. Some limited terrestrial faunal exchanges that occur during the Messinian between southwestern Europe and northwestern Africa do not deeply affect the general faunal dynamics. Both allochthonous cohorts of immigrants become rapidly extinct. Several endemic rodent faunas, indicating insular conditions, have been reported from the southern edge of the western European continent from the middle Miocene up to the Pliocene. All show low taxonomic diversity, strong endemism and short survival. Some of them, like those of the Gargano Islands during the late Miocene, underwent peculiar morphological changes and also speciation. The large number of rodent genera coevolving in the Gargano Islands is indicative of the large surface areas of these islands. The general geographic pattern of southwestern Europe during the Neogene may therefore correspond to a large continental province including Spain and southern France with some kind of fast-modifying archipelago on its southern rim.

The role of vagal efferent activity in the cold air potentiation of exercise-induced asthma was assessed by exercising nine subjects who breathed air at ambient and subfreezing temperatures before and after cholinergic blockade. Lung volumes and maximal expiratory flow volume curves with air and with 80% helium-20% oxygen were obtained before and 5--10 min after each challenge. Isovolume comparisons of maximal expiratory flow rates with the two gases were used to assess relative contributions of large and small airways to flow limitation. Exercise under ambient conditions resulted in the expected airway obstruction and cold air exaggerated the response. Atropine pretreatment had no effect on the cold air potentiation. After atropine with ambient air exercise, there was an increase in the relative contribution of large airways to flow limitation, whereas exercise with cold air resulted in an increase in the contribution of small airways. We concluded that the potentiating effects of cold air are local and suggest that the immediate stimulus is related to cooling of intrathoracic airways.

Eucapnic voluntary hyperventilation (EVH) of cold, dry air has been shown to be an effective stimulus for bronchoconstriction in people with reactive airways. The system for respiratory heat exchange (RHE) challenge can be greatly simplified from what is presently used. A relationship was derived which predicts that a single fraction of inspired CO2 (0.0489) will produce near normal alveolar CO2 over a wide range of voluntary hyperventilation. This relationship was verified in 19 normal subjects who performed a total of 110 periods of hyperventilation with minute ventilation (VE) randomly distributed between 40 and 105 L/min. The experimentally determined CO2 production of the voluntary hyperventilation was found to be 3.72 ml/min per L/min over a range of VE from 40 to 105 L/min. Next, a group of 10 patients with exercise-induced asthma (EIA) were challenged with a standard exercise protocol, ventilating ad libitum from a source of dry air at room temperature. On another day, the same pattern of VE, and hence RHE, was required of them using the simplified EVH scheme. The average decreases in forced expiratory volume in one second and specific airway conductance were 32 +/- 10% and 66 +/- 13%, respectively, after the exercise challenge, and 33 +/- 12% and 73 +/- 12% after EVH. The difference between corresponding mean values was not significant. We conclude that a simplified EVH challenge can be done using a single dry gas mixture without the need for cooling inspired gas or monitoring end-tidal fraction of CO2. This test can be used to identify and study patients with EIA without the requirement for an exercise challenge or the need for elaborate gas conditioning and monitoring equipment.

We have hypothesized that it is the total heat flux in the tracheobronchial tree during exercise that determines the degree of postexertional obstruction in asthma, and have developed quanititative expressions that relate these two events. We tested this hypothesis by comparing the observed responses to exercise, while our subjects inhaled dry air at various temperatures ranging from subzero to 80 degrees C in a random fashion, to those that we predicted would occur based upon calculations of respiratory heat exchange. We further determined if heat could be transferred from the inspired air to the mucosa so as to offset evaporative losses from the airways. The observed responses fell as air temperature was increased from -11 to +37 degrees C and exactly matched theoretical predictions. Above 37 degrees C, the observed response exceeded predictions, indicating that it was not possible to provide sufficient heat per se in the air to offset the vaporization of water. However, when small amounts of water vapor were added to the inspirate at high temperatures, bronchospasm was virtually abolished and the response again closely matched theoretical expectations. We conclude that the magnitude of exercise-induced asthma is directly proportional to the thermal load placed on the airways and that this reaction is quantifiable in terms of respiratory heat exchange.

Eight normal individuals performed 10 min of bicycle exercise at 80% of their predicted maximum workload while breathing air at 22 C, saturated with water vapor and air at -40 C, dry. Rectal temperature and temperature at various locations along the length of the esophagus were measured during the exercise period. Pulmonary mechanics were measured before and 5 to 10 min after exercise. Temperature in the lower third of the esophagus was in close agreement with rectal temperature and was unaffected by level of respiratory heat exchange. Upper esophageal temperature decreased substantially during exercise, the magnitude of the decrease being dependent upon proximity to intrathoracic airways and the level of respiratory heat exchange. Subjects bronchodilated in response to exercise breathing warm air but this response was abolished by exercise breathing -40 C air. We conclude that at sufficiently high levels of respiratory heat exchange, normal individuals exhibit mild bronchoconstriction qualitatively similar to the severe bronchospasm induced in asthmatics by modest increases in respiratory heat exchange.

It was previously demonstrated that the magnitude of post exertional asthma is proportional to the heat exchange that occurs within the airways. Since the level of ventilation is an important determinant of the quantity of heat transferred from the mucosa, it was reasoned that if we simulated the hyperpnea of exercise by hyperventilation, heat exchange would be produced similar to that seen with exercise, and thus equivalent bronchial obstruction. To test this hypothesis, 8 asthmatics performed eucapnic hyperventilation to mean levels of 63 and 44 L/min while they breathed dry air at subfreezing (-12 C) and room temperature (23 C) and fully saturated air at room and body temperature through a heat exchanger in a random order. Hyperventilation at body conditions (0 heat flux) did not result in any change in pulmonary mechanics. However, as the water content and temperature of the inspirate were decreased, thus increasing the thermal burden on the airways at maximal ventilation (V sub E), the bronchospastic response progressively increased. Decreasing the thermal burden by decreasing V sub E proportionally reduced the response. From this we conclude that the major stimulus for exercise-induced asthma is heat loss from the mucosa with subsequent cooling, which is precipitated by the hyperpnea of exercise but not exercise per se.

International audience; It has been suggested that flood basalts in the Deccan (India) might be associated with events at the Cretaceous-Tertiary boundary (KTB). A search for iridium in 47 samples from lava flows and inter-trap sediments in the Deccan yields negative results. Concentrations are not statistically different from zero, with a minimum detection level on the order of 0.1 ng.g$^{-1}$ (ppb). This does not help to constrain the debate on the internal vs external origin of KTB boundary events, since for instance Ir could have been outgassed from the magma, and original concentrations of only 0.05 ng.g$^{-1}$ prior to outgassing aresufficient to account for the worldwide Ir excess mass at the KTB.

Multiple aspects of pulmonary mechanics were measured before and after bronchial challenges consisting of hyperpnea with cold air inhalation in 20 normal control subjects, 16 subjects with hay fever, and 44 asymptomatic asthmatics. These challenges had no effect on the lung function of the normal subjects. In the hay fever group, however, postchallenge mechanics changed a small, but significant, amount, e.g., mean decrease in forced expiratory volume in one second (FEV1) was -5.1 +/- 1.7% (SEM). The asthmatics had a much more marked response (mean fall in FEV1, -32.7 +/- 2.6%). There was considerable overlap between the responses of the normal subjects and those with hay fever, but no overlap at all between asthmatic and normal subjects. The only subjects with hay fever whose responses overlapped the asthmatic response were those who had histories of occasional episodes of wheezing. This pattern of response suggests that the use of hyperpnea and subfreezing air is a very sensitive and highly specific means of detecting increased air reactivity.

To determine if subclinical pulmonary edema occurs commonly at high altitude, 25 soldiers participated in two consecutive 72-h field exercises, the first at low altitude (200–875 m) and the second at high altitude (3,000–4,300 m). Various aspects of ventilatory function and pulmonary mechanics were measured at 0, 36, and 72 h of each exercise. Based on physical examination and chest radiographs there was no evidence of pulmonary edema at high altitude. There was, however, an immediate and sustained decrease in vital capacity and transthoracic electrical impedance as well as a clockwise rotation of the transpulmonary pressure-volume curve. In contrast, closing capacity and residual volume did not change immediately upon arrival at high altitude but did increase later during the exposure. These observations are consistent with an abrupt increase in thoracic intravascular fluid volume upon arrival at high altitude followed by a more gradual increase in extravascular fluid volume in the peribronchial spaces of dependent lung regions.

Exposure to airblast can result in injury to the lungs and other gas-containing organs. The mechanism of lung injury is not clearly understood, but may be related to the rapid increase in intrathoracic pressure (ITP) which is produced when the blast wave strikes the chest wall. The purpose of this study was to determine if ITP during airblast would be influenced by several different types of protective clothing. Ten healthy young male volunteers were exposed to airblast while standing face-on and wearing 1) military fatigues (control condition); 2) fatigues with field jacket; 3) fatigues with ballistic armor vest; 4) fatigues with ceramic vest; 5) fatigues with ceramic vest over the ballistic vest. The incident blast waves simulated artillery muzzle blast. In each subject, an esophageal strain-gauge pressure transducer measured ITP during the blast. The pressure signal was analyzed for ITPmax, and maximum rate of rise of ITP (dP X dt max-1). In addition, the power density spectra of each ITP wave was computed and the peak frequency (fp) and centroid frequency (fc) were calculated. When the subjects wore the ballistic vest, the mean ITPmax was higher (p less than 0.05) than when they were exposed to airblast in fatigues alone. ITPmax was not influenced by the other clothing ensembles. The mean dP X dtmax-1 was not significantly different with any protective clothing ensemble. Clothing had no significant effect of fp, but with the ballistic vest, the mean calculated fc was higher (p less than 0.05) than that for the fatigues alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Strain resulting from the collision of India with Asia has caused fundamental changes to Asian drainage patterns, but the timing and nature of these changes are poorly understood. One frequently proposed hypothesis involves the connection of the palaeo Tsangpo drainage to a precursor to the Irrawaddy River of central Myanmar in the Palaeogene. To test this hypothesis, we studied the provenance of Palaeogene fluvio-clastic sedimentary rocks that crop out in central Myanmar, namely the Late Middle Eocene–Early Oligocene Pondaung and Yaw Formations. Isotopic analysis on bulk-rock and petrographic data indicate a primary magmatic arc source, and a secondary source composed of recycled, metamorphosed basement material. Although the exact location of both sources is hardly distinguishable because Burmese and Tibetan provinces share common lithological features, the presence of low-grade metamorphic fragments, the heterogeneity in Sr–Nd isotopic values of bulk sediments and westward-directed palaeoflow orientations indicate a proximal source area located on the eastern Asian margin. Central Myanmar was the locus of westward-prograding deltas opening into the Indian Ocean, supplied by the unroofing of an Andean-type cordillera that extended along the Burmese margin. We found no evidence to support a palaeo Tsangpo–Irrawaddy River, at least during the Late Eocene.

Strain resulting from the collision of India with Asia has caused fundamental changes to Asian drainage patterns, but the timing and nature of these changes are poorly understood. One frequently proposed hypothesis involves the connection of the palaeo Tsangpo drainage to a precursor to the Irrawaddy River of central Myanmar in the Palaeogene. To test this hypothesis, we studied the provenance of Palaeogene fluvio-clastic sedimentary rocks that crop out in central Myanmar, namely the Late Middle Eocene–Early Oligocene Pondaung and Yaw Formations. Isotopic analysis on bulk-rock and petrographic data indicate a primary magmatic arc source, and a secondary source composed of recycled, metamorphosed basement material. Although the exact location of both sources is hardly distinguishable because Burmese and Tibetan provinces share common lithological features, the presence of low-grade metamorphic fragments, the heterogeneity in Sr–Nd isotopic values of bulk sediments and westward-directed palaeoflow orientations indicate a proximal source area located on the eastern Asian margin. Central Myanmar was the locus of westward-prograding deltas opening into the Indian Ocean, supplied by the unroofing of an Andean-type cordillera that extended along the Burmese margin. We found no evidence to support a palaeo Tsangpo–Irrawaddy River, at least during the Late Eocene.