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The volcanic events of the last 3,000 years at San Salvador volcanic complex are reviewed using detailed stratigraphic records exposed in new excavations between 2005 and 2007, at El Cambio archeological site (Zapotitan Valley, El Salvador), and in other outcrops on the northern and northwestern sectors of the complex. The sequences that overlie Tierra Blanca Joven (cal. 429 ± 107 ad), from the Ilopango caldera, comprise the Loma Caldera (cal. 590 ± 90 ad) and El Playon (1658–1671) deposits and the San Andres Tuff (cal. 1031 ± 29 ad), related to El Boqueron Volcano. The surge deposits within the El Playon, San Andres Tuff and overlying Talpetate II sequences indicate the significance of phreatomagmatic phases in both central vent and flank eruptions during the last 1,600 years. Newly identified volcanic deposits underlying Tierra Blanca Joven at El Cambio extend the stratigraphic record of the area to 3,000 years bp. Paleosols interstratified with those deposits contain cultural artifacts which could be associated with the Middle Preclassic period (900–400 bc). If correct, human occupation of the site during the Preclassic period was more intense than previously known and volcanic eruptions must have affected prehistoric settlements. The archeological findings provide information on how prehistoric populations dealt with volcanic hazards, thousands of years ago in the eastern Zapotitan Valley, where several housing projects are currently being developed. The new stratigraphic and volcanological data can be used as a basis for local and regional hazard assessment related to future secondary vent activity in the San Salvador Volcanic Complex.

We combine geodetic, structural, and paleomagnetic data from El Salvador with Global Positioning System (GPS) data from southern Honduras and Nicaragua to describe the motions of the Salvadoran and Nicaraguan forearcs and determine the location and style of faulting across the Gulf of Fonseca offset of the volcanic arcs of eastern El Salvador and western Nicaragua. Finite-element modeling of GPS measurements at 35 sites in El Salvador, southern Honduras, and Nicaragua indicates that the Nicaraguan and Salvadoran forearcs both move west to northwest, parallel to their respective trenches, at 15 ± 2 mm yr −1 (95% limit) in a Caribbean plate reference frame. The similar motions of the two forearcs, despite an ∼20°–25° difference in the obliquity of subduction beneath them and absence of any significant convergence obliquity offshore from El Salvador, are consistent with a recent hypothesis that the Nicaraguan forearc pushes the Salvadoran forearc to the northwest, possibly driven by northwestward lateral escape of the Central America forearc from its collision zone with the Cocos Ridge offshore from Costa Rica. The Gulf of Fonseca and adjacent eastern El Salvador form an ∼60-km-wide extensional zone with E-W elongation, determined by diffuse seismicity, GPS velocities, and numerous young, N-S–striking normal faults mapped with a 10 m digital elevation model (DEM), structural measurements, and Lidar (light detection and ranging). Strike-slip earthquakes in the Fonseca pull-apart structure and evidence for modest (∼10°) vertical-axis fault block rotations from paleomagnetic measurements at 33 sites in the Fonseca pull-apart structure both indicate that extension may be accompanied by bookshelf faulting.

The El Salvador earthquake of 13 February 2001 (Mw 6.6) caused tectonic rupture on the El Salvador fault zone (ESFZ). Right-lateral strike-slip surface rupture of the east–west trending fault zone had a maximum surface displacement of 0.60 m. No vertical component was observed. The earthquake resulted in widespread landslides in the epicentral area, where bedrock is composed of volcanic sediments, tephra, and weak ignimbrites. In the aftermath of the earthquake, widespread damage to houses and roads and the hazards posed by landslides captured the attention of responding agencies and scientists, and the presence of surface-fault rupture was overlooked. Additionally, the tectonic context in which the earthquake took place had not been clear until mapping of the ESFZ was completed for the present study.We identified several fault segments, the distribution of surface ruptures, the aftershock pattern, and fault-rupture scaling considerations that indicate the 21-km-long San Vicente segment ruptured in the 2001 event. Static Coulomb stress transfer models for the San Vicente rupture are consistent with both aftershock activity of the 2001 sequence and ongoing background seismicity in the region. At Mw 6.6, the 2001 earthquake was of only moderate magnitude, yet there was significant damage to the country’s infrastructure, including buildings and roads, and numerous deaths and injuries. Thus, earthquake hazard and risk in the vicinity of the ESFZ, which straddles the city of San Salvador with a population of >2 million, is high because even moderate-magnitude events can result in major damage, deaths, and injuries in the region.

We report the stratigraphic sequence of the 2005 eruption of Ilamatepec volcano together with sedimentological and chemical analyses of its products. Structural and textural characteristics of the deposits indicate that the eruption was driven by a small-volume rhyolitic intrusion at shallow levels, which resulted first in the collapse of the existing hydrothermally altered fan of previous deposits inside the crater lake, driving phreatic explosions with launching of blocks on ballistic trajectories; later the magma interacted with lake waters producing several hydromagmatic pyroclastic density currents (PDCs). These flows were energetic enough to knock down pine trees up to distances of 1.8 km from the crater in the E-NE sector of the volcano. Finally, ejection of ballistic blocks that landed on previously emplaced, wet pyroclastic density current deposits, caused the generation of a lahar that flowed down the steep eastern flank toward the El Jabillal gully. Subsequent lahars occurred as a result of intense rain caused by hurricane Stan. Radiocarbon ages on paleosols and charcoal fragments, separating previous volcanogenic sequences, indicate that similar eruptions have occurred more frequently in the past centuries, than previously thought. The new data confirms that Ilamatepec volcano is one of the most active volcanoes in El Salvador. Nevertheless, more detailed studies of the eruptive sequence of Ilamatepec volcano are mandatory to establish future eruptive patterns.

SUMMARY We invert GPS velocities from 32 sites in El Salvador, Honduras and Nicaragua to estimate the rate of long-term forearc motion and distributions of interseismic coupling across the Middle America subduction zone offshore from these countries and faults in the Salvadoran and Nicaraguan volcanic arcs. A 3-D finite element model is used to approximate the geometries of the subduction interface and strike-slip faults in the volcanic arc and determine the elastic response to coupling across these faults. The GPS velocities are best fit by a model in which the forearc moves 14–16 mm yr −1 and has coupling of 85–100 per cent across faults in the volcanic arc, in agreement with the high level of historic and recent earthquake activity in the volcanic arc. Our velocity inversion indicates that coupling across the potentially seismogenic areas of the subduction interface is remarkably weak, averaging no more than 3 per cent of the plate convergence rate and with only two poorly resolved patches where coupling might be higher along the 550-km-long segment we modelled. Our geodetic evidence for weak subduction coupling disagrees with a seismically derived coupling estimate of 60 ± 10 per cent from a published analysis of earthquake damage back to 1690, but agrees with three other seismologic studies that infer weak subduction coupling from 20th century earthquakes. Most large historical earthquakes offshore from El Salvador and western Nicaragua may therefore have been intraslab normal faulting events similar to the M w 7.3 1982 and M w 7.7 2001 earthquakes offshore from El Salvador. Alternatively, the degree of coupling might vary with time. The evidence for weak coupling indirectly supports a recently published hypothesis that much of the Middle American forearc is escaping to the west or northwest away from the Cocos Ridge collision zone in Costa Rica. Such a hypothesis is particularly attractive for El Salvador, where there is little or no convergence obliquity to drive the observed trench-parallel forearc motion.

p27 immunostaining is related to prognosis in malignant mesothelioma Aims: To evaluate the prognostic value of the proliferation-associated antigen p27 in malignant mesothelioma. Methods and results: Sections from 36 patients with malignant mesothelioma were immunohistochemically stained for the p27 antigen. The results were quantified by recording the proportion of positively stained nuclei and these data were tested for association with patient survival. p27 expression was also compared with tumour type, MIB-1 expression, apoptotic and mitotic indices. Patients with pleural malignant mesothelioma showing low p27 expression (

Five new stepwise-heating 40 Ar/ 39 Ar ages and one new high-sensitivity 14 C date of ash-fall and ash-flow deposits from late Quaternary silicic volcanoes in northern Central America document the eruption rates and frequencies of five major rhyodacite and rhyolite calderas (Atitlan, Amatitlan, Ayarza, Coatepe- que, and Ilopango) located north of the basalt, ande- site, and dacite stratovolcanoes of the Central Ameri- can volcanic front. These deposits form extensive time- stratigraphic horizons that intercalate regionally, and knowledge of dates and stratigraphy provides a valua- ble framework for age determinations of more local- ized volcanic and nonvolcanic events. The new data, es- pecially when integrated with previous stratigraphic and dating work, show that all five calderas erupted several times in the past 200 ka and, despite a lack of historic activity, should be considered as active centers that could produce highly explosive eruptions again. Because of their locations near the highly vulnerable economic hearts of Guatemala and El Salvador, the risks of eruptions from these calderas should be care- fully considered along with risks of major earthquakes and volcanic front volcanoes, which are much more fre- quent but inflict less severe and extensive damage. This

Individuals homozygous for the e2 allele encoding apolipoprotein E exhibit a remnant removal defect and accumulate substantial levels of intestinally derived particles containing apolipoprotein B-48 (apoB-48). Such lipoproteins were isolated from the plasma of E2/E2 individuals, and further purified by affinity chromatography using a polyclonal antibody specific for selective binding and removal of apoB-100-containing lipoproteins. The unbound lipoproteins, termed chylomicron remnants, were particles with average hydrated diameters of 31.2 nm as determined by dynamic light scattering. They contained apoB-48 and ApoE as their only protein components. The number of apoB-48 molecules on each lipoprotein was assessed by counting the number of antibody molecules bound to the surface of the chylomicron remnants, using either a monoclonal antibody specific for a single epitope on apoB-48 or a mixture of two such monoclonal antibodies specific for widely separated epitopes. The results of this analysis seem unambiguous: no more than one apoB-48 resides on the chylomicron remnant. Because apoB appears to be unable to transfer among lipoprotein particles, it may be inferred that nascent chylomicrons also contain a single copy of apoB-48.

San Vicente is a composite volcano whose oldest volcanic events (2.2 Ma) are recorded in the westernsector, where the remnants of the older La Carbonera edifice outcrop. This volcanic center, which produced mildlytholeiitic to transitional lavas, collapsed during a plinian eruption, giving rise to the formation of a partially preservedcaldera (La Carbonera caldera). The renewal of volcanic activity started with clearly calc-alkaline lavas, mostly two-pyroxene andesites, that built up the San Vicente volcanic edifice. Crystal fractionation had primary control on magmaevolution.The event that triggered the caldera forming plinian eruption is still uncertain; we have some texturalevidences of mixing/mingling with more mafic magmas, but this process seems to be delimited to fewsamples. A major role could have been played by the tectonic instability related to the first stages of centralgraben opening. Durante 1993 un equipo de investigadores italianos y salvadoreños realizó investigaciones en elvolcán de San Vicente, El Salvador, con el objetivo de definir la evolución petrológica y volcánica de dichocentro volcánico. Estos estudios formaron parte de estudios preliminares de geotermia en el área. Los productosvolcánicos más antiguos (2,2 M.a.) se encuentran en el sector occidental del volcán de San Vicente, en dondeafloran los depósitos de la estructura volcánica La Carbonera. Este centro volcánico, el cuál produjo lavasmedianamente toleíticas a transicionales, colapsó posterior a una erupción pliniana y formó una calderapreservada parcialmente y definida como La Carbonera. La actividad volcánica se reanuda con la producción delavas calco-alcalinas, en su mayoria andesitas de dos piroxenos. El proceso magmático principal es el defraccionamiento de cristales. El evento que causó la erupción pliniana es todavia desconocido. Tenemos ciertaevidencia textural de “mixing/mingling” de magmas, pero esto sólo se observa en algunas muestras. Lainestabilidad tectónica del área debido a la formación del graben central de El Salvador pudo haber tenido unpapel muy importante como causa de la erupción.

To evaluate the prognostic value of the proliferation-associated antigen p27 in malignant mesothelioma.Sections from 36 patients with malignant mesothelioma were immunohistochemically stained for the p27 antigen. The results were quantified by recording the proportion of positively stained nuclei and these data were tested for association with patient survival. p27 expression was also compared with tumour type, MIB-1 expression, apoptotic and mitotic indices. Patients with pleural malignant mesothelioma showing low p27 expression (53% of cells positive) survived for significantly shorter periods of time than those with high p27 expression (or = 53% of cells positive) (P=0.04). The 50% survival time of subjects with low p27 was 4-6 months whereas for those with high p27 expression it was 10-11 months. There was no significant association between p27 expression and MIB-1, apoptotic or mitotic indices.Low p27 expression in pleural malignant mesothelioma is associated with a significantly worse prognosis. p27 appears to be an independent prognostic variable which may be of value in counselling patients with malignant mesothelioma.

This map is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. NOTE: Although the map shows sharp boundaries for hazard zones, the degree of hazard does not change abruptly at these boundaries. Rather, the hazard decreases gradually as distance from the volcano increases (small volume events are more common than large volume events). Areas immediately beyond outer hazard zones should not be regarded as hazard-free, because the boundaries of hazard zones can be located only approximately, especially in areas of low relief. Many uncertainties about the source, size, and mobility of future events preclude locating the boundaries of zero-hazard zones precisely.

We assessed the value of cytology in the rapid diagnosis of bronchopneumonia at post mortem. Cytology scrapes were taken from 249 lung lobes during 50 autopsies. Slides were stained with a modified Giemsa technique and a neutrophil polymorph score recorded on a scale of 0-3. Histology blocks from the same area were then scored for the degree of bronchopneumonia present. Bronchopneumonia was found histologically in 22 patients, but macroscopic examination had identified only eight of these. A cytological neutrophil polymorph score of 2 or more to indicate bronchopneumonia yielded a sensitivity of 52% and a specificity of 98% in terms of lobes. This gave a positive predictive value of 92% and a negative predictive value of 86% for the presence of bronchopneumonia. All eight patients with a cytology score of 3 had histological evidence of bronchopneumonia. Conversely, all patients with a definitive diagnosis of bronchopneumonia exhibited cytology scores of at least 1. Post mortem cytology scrapes reliably predict bronchopneumonia and are superior to gross examination. This is a rapid, reliable and cheap method that can be readily performed in all necropsy practices.

In our last issue, Mr. Dewhirst set out the case for civilianization. The following article by the senior police officer who was in charge of administration in Kent prior to his own post being civilianized, explains how the change-over was made.