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We report a rare case of a male child aged 4 years and 5 months who was diagnosed with a coronary artery fistula and left single coronary artery. Pre-operative evaluation with echocardiography and selective angiography showed a dilated and tortuous single coronary artery draining into the right ventricular outflow tract. The coronary fistula was ligated. The post-operative and clinical courses were uneventful.

A kinetic study about the phase limonite (FeO(OH)-nH2O) was performed through X-ray diffraction, μ-Raman spectroscopy and Mossbauer spectroscopy. The oxide powder sample was extracted from Taraco district, Huancane province of Puno (Peru). X-ray diffraction identified the phase goethite as the main mineralogical component, and then the sample was subjected to in-situ heat treatment in the temperature range: 100 to 500°C in oxidizing (air) and inert (nitrogen) atmospheres. The goethite phase remains stable in this range: room temperature to 200°C. Between 200°C to 250°C there is a phase transition: α-Fe3 + O(OH) → α-Fe2O3, i.e., from goethite to hematite phase, taking as evidence the evolution of the diffraction profiles. At 200°C spectra shows the start of broadened magnetic component and it was adjusted through of a magnetic distribution giving a mean field of 38.6T and a relative area of 52.9%, which is a characteristic of goethite. Also, it is noticed the presence of a small amount of hematite with a mean field of 49.0T linked with a superparamagnetic broadened doublet of relative area of 47.1% where the domains of the particles have sizes smaller than 100 A and it is evidence the superparamagnetic limit; i.e., the superparamagnetic effect tends toward a distribution of magnetic fields. Moreover, the Raman spectra of the in-situ thermal treatment, support the transition at 290°C through the transformation of characteristic bands of goethite to hematite phase at the frequency range from 200 to 1,800 cm − 1.

Resumen Introduccion Una actividad esencial de los laboratorios de andrologia es el control de la calidad externo. Para la evaluacion de la eficacia de los laboratorios participantes en los Programas de Supervision Externa de la Calidad (PSEC) se utilizan limites admisibles de error, de manera que el resultado de un laboratorio sera considerado aceptable si se encuentra dentro de dichos limites. En este momento los limites admisibles de error dependen en gran medida de los criterios de los organizadores del PSEC. Nuestro objetivo es comparar los diferentes criterios descritos en la ISO 13528:2005 para el calculo de los comentados limites admisibles de error en los PSEC para la concentracion espermatica. Material y metodos Los datos que se analizaran en este estudio son los valores de la media y desviacion tipica (DS) obtenidos sobre muestras control independientes, provenientes de dos PSEC. Se fijaron cuatro estrategias diferentes de calculo de los limites admisibles de error segun la ISO 13528:2005: 1) basada en los resultados de los laboratorios participantes; 2) basada en los resultados de los laboratorios expertos; 3) utilizando las especificaciones de calidad basadas en la variabilidad biologica, estado del arte y opinion de los clinicos; y 4) utilizando las especificaciones de calidad y ajustando por la incertidumbre del valor asignado. Resultados Con la estrategia 1 y 2 se obtienen limites admisibles de error muy amplios. Al contrario, con la estrategia 3, basada solo en las especificaciones de calidad, se obtienen limites muy estrictos. Sin embargo, con la estrategia 4 obtenemos valores de intervalos de aceptacion intermedios en comparacion con las demas estrategias. No se observan diferencias en los limites admisibles de error en las estrategias 3 y 4 al variar el modelo empleado para el calculo de las especificaciones de calidad analitica. Discusion Los PSEC de concentracion espermatica deberian utilizar una estrategia ajustada para la incertidumbre del valor asignado para establecer los limites admisibles de error, ya que con ella se obtienen intervalos de aceptacion clinicamente utiles, de manera que los valores incluidos en ellos nos llevan a decisiones clinicamente similares. El definir adecuadamente a los laboratorios expertos es mas importante que el modelo escogido para estimar las especificaciones de calidad analitica en un PSEC de concentracion espermatica.

Photoluminescent nanopillars are fabricated by replication from nanoporous anodic alumina via template wetting using polymer from different chemical families: polyfluorenes, PPV derivatives and thiophenes. The experimental process entails infiltration of a polymeric solution into the pores of the template with an average pore diameter of 225 nm and a pore depth of 500 nm. The geometric features of the resulting structures are characterized with environmental scanning electron microscopy (ESEM). The influence of nanostructure in the photophysical properties of the polymer is investigated by UV-Vis absorbance and photoluminescence measurements. Polarized Raman spectroscopy characterization is also performed in order to study the different polymer conformation into the nanoporous template. The nanopillars obtained are interesting in many applications such as nanostructured solar cells and polymer light emitting diodes. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Poly(9,9-di-n-octylfluorene-alt-benzothiadiazole) (F8BT) nanopillars were fabricated using the template wetting method. In order to obtain nanostructures, self-ordered nanoporous alumina has been employed as template. Environmental scanning electron microscopy (ESEM) images reveal that the resulting F8BT structures present diameters ∼225 nm and heights ∼500 nm. The influence of the template and the solvent in the photophysical properties of the F8BT structures have been studied by UV-Vis absorption, photoluminescence and Raman spectroscopy. These polymer structures have a wide range of potential applications due to its optical and electrical properties.

The prevalence of low HDL-C levels in an HIV population and its related factors was investigated. We undertook a multicenter, cross-sectional study of all HIV patients on regular follow-up in five hospitals (Southern Spain). A physical examination and fasting laboratory analysis were performed and a questionnaire about cardiovascular risk factors was provided. One thousand and seventy-two patients were included, 43.8% of whom had low HDL-C levels. The prevalence of low HDL-C was higher among patients diagnosed with AIDS, those not on antiretroviral therapy, those with a detectable HIV viral load, those with CD4 cell counts ≤350 cells/μl, smokers, and those with hypertriglyceridemia. For patients on antiretroviral therapy, the prevalence of low HDL-C was higher for those on protease inhibitors than those taking nonnucleoside reverse transcriptase inhibitors. In the multivariate analysis, low HDL-C levels were associated with tobacco use (OR 1.37, 95% CI 1.04-1.8; p = 0.04), hypertriglyceridemia (OR 2.94, 95% CI 2.2-3.8; p 0.00001), CD4 cells count ≤350 cells/μl (OR 1.74, 95% CI 1.2-2.3; p 0.0001), and a detectable HIV viral load (OR 1.85, 95% CI 1.3-2.5; p 0.0001). The immunological and virological conditions, in addition to traditional cardiovascular risk factors such as tobacco use and hypertriglyceridemia, affect HDL-C levels in HIV-infected patients. For patients on antiretroviral therapy, the use of protease inhibitors is associated with a higher probability of low levels of HDL-C. Although it is not clear if the higher HDL-C levels associated with antiretroviral use are surrogates for decreased cardiovascular disease risk, this may be another reason to start antiretroviral therapy earlier.

The significance of the selective enrichment in omega-3 essential fatty acids in photoreceptors and synaptic membranes of the nervous system has remained, until recently, incompletely understood. While studying mechanisms of cell survival in neural degeneration, we discovered a docosanoid synthesized from unesterified docosahexaenoic acid (DHA) by a 15-lipoxygenase (15-LOX), which we called neuroprotectin D1 (NPD1; 10R,17S-dihydroxy-docosa-4Z,7Z,11E,13E,15E,19Z hexaenoic acid). This lipid mediator is a docosanoid because it is derived from the 22 carbon (22C) precursor DHA, unlike eicosanoids, which are derived from the 20 carbon (20C) arachidonic acid (AA) family member of essential fatty acids. We discovered that NPD1 is promptly made in response to oxidative stress, as a response to brain ischemia-reperfusion, and in the presence of neurotrophins. NPD1 is neuroprotective in experimental brain damage, in oxidative-stressed retinal pigment epithelial (RPE) cells, and in human brain cells exposed to amyloid-beta (Abeta) peptides. We thus envision NPD1 as a protective sentinel, one of the very first defenses activated when cell homeostasis is threatened by imbalances in normal neural function. We provide here, in three sections, recent experimental examples that highlight the specificity and potency of NPD1 spanning beneficial bioactivity during initiation and early progression of neurodegeneration: (1) during retinal signal phototransduction, (2) during brain ischemia-reperfusion, and (3) in Alzheimer's disease (AD) and stressed human brain cell models of AD. From this experimental evidence, we conclude that DHA-derived NPD1 regulation targets upstream events of brain cell apoptosis, as well as neuro-inflammatory signaling, promoting and maintaining cellular homeostasis, and restoring neural and retinal cell integrity.

Photoluminescent micro- and nanopillars are fabricated by replication from macroporous silicon and nanoporous anodic alumina via template wetting using different conducting polymers. The geometric features of the resulting structures are characterized through environmental scanning electron microscopy. The influence of the porous dimension in the photophysical properties of the polymeric structures is investigated by absorption and emission measurements. By means of micro-X-ray diffraction we analyze the amorphous-crystalline nature of the fabricated structures. These structures can be interesting as hole conducting donors in different applications such as nanostructured solar cells and polymer light emitting diodes.

In combination, microinvertebrates, calcareous algae (Charophyta), and the stable isotopes from ostracodes and gyrogonites (the calcareous remains of charophytes) are a powerful tool for reconstructing paleoclimates. This study compares the paleoenvironmental signatures of land and aquatic mollusks, ostracodes, and charophytes with stable-isotope (δ 18 O and δ 13 C) values for Cypridopsis sp. (an ostracode) and the gyrogonites of Chara globularis and Nitella flexilis. Each individual signature contributes its own evidence of environmental change between 1890 ± 40 years B.P. and post–750 ± 40 years B.P. at archaeological site 41PT185/C in northern Texas, United States of America. The interpretation of the combined data permits a detailed reconstruction of paleoclimatic variability at the transition from the Medieval Climatic Anomaly to the Little Ice Age, allowing inferences about the impact of such environmental change on human populations in this part of the U.S. Southwest.

Analyses of the impact on sentencing when alcohol and drug‐related mitigation is used in the sentencing phases of capital murder trials is virtually absent from the existing literature. The present study addresses this by exploring the effect of having mitigation with alcohol and drug themes accepted in a large sample (n = 804) of capital murder trials in North Carolina. Logistic regression analyses that include a number of relevant control variables reveal no substantive impacts of having alcohol mitigation accepted by capital murder juries, but drug mitigators that were either accepted or rejected by juries were associated with an increased risk of receiving a death sentence. Possible reasons for the results and their implications are discussed and suggestions are made for further study of the effects of alcohol/drug mitigation in capital trials.

This study analyzes the structure and composition of ant communities in citrus orchards in Catalonia (northeast Spain) and compares them with the ant fauna found in natural communities of the region. In the citrus orchards considered in this study, the most abundant species were Lasius niger and Pheidole pallidula, which are behaviorally dominant species. Two other dominant species, Linepithema humile and Tetramorium caespitum, were also abundant, although only in one orchard. Species richness and diversity in the studied orchards were low compared with natural communities: although in orchards, there were few species and low diversity values, in natural communities, the number of species was higher and diversity also increased. This reduction of species richness and diversity was not modified by edge effects: only light and local differences were found between the inner part of the orchards and the orchard margins, and differences among orchards were greater than differences between inner parts and edges. The activity peaks of the different ant species actively foraging on these citrus orchards were distributed throughout the whole activity period of ants. Overall, the composition of ant communities present in the citrus orchards of this study was extremely poor. This agrees with the fact that monocultures are ecosystems associated with an inevitable loss of biodiversity and abundance of insect populations. © 2009 Entomological Society of America.

Polymer-dispersed liquid crystals (PDLCs) are liquid crystal dispersions within a polymer matrix. PDLCs have attracted the interest of researchers for their applications as light shutters, smart windows, and active displays. Herein, we report on the preparation and characterization of PDLCs by a combination of two types of induced phase separation. Experimental results show the nucleation and growth of the E7 liquid crystal droplets from poly(styrene), poly(methylmethacrylate) or poly(dimethylsiloxane) which are used as a polymeric matrix. The time evolution of liquid crystal droplets in terms of liquid crystal domain diameter was quantified. PDLCs were characterized by Fourier transform infrared spectroscopy and Raman spectroscopy.

We report the results of a protocol for the diagnosis and treatment of pediatric non-Hodgkin lymphomas (NHL) conducted in Nicaragua in the context of an international collaborative program. Fifty-three children with NHL treated between 1996 and 2003 were retrospectively evaluated. Therapy was designed based on local drug availability and affordability with dose and schedule adaptations for Burkitt and lymphoblastic lymphomas. With a median follow-up of 3 years, the projected 9-year overall survival was 63% and event-free survival 53%. The treatment was efficacious, feasible, and well tolerated in spite of the local socio-economical conditions.

In this article, we propose a software architecture for controlling a mobile robot that works as a guide on human environments. The architecture is divided into three broad action modules lead by a supervisor. The decision is based on current user behavior in order to provide better service to people.

Summary Background Most available information on carbapenemase-producing Enterobacteriaceae (CPE) is usually associated with specific types of infection or patient or with descriptions of outbreaks. The aim of this study was to comprehensively analyse the clinical epidemiology, clinical features and outcomes of colonisation and infections due to CPE in Spain. Methods A multicentre prospective cohort study was carried out in 34 Spanish hospitals from February to May 2013. All new patients testing positive for CPE in clinical samples were included. Logistic regression was used to identify predictors of mortality. Results Overall, 245 cases were included. The most frequent organism was Klebsiella pneumoniae (74%) and the carbapenemases belonged to the OXA-48 (74%), metallo-β-lactamase (MBL) (24%) and KPC (2%) groups. Acquisition was nosocomial in 145 cases (60%) and healthcare-associated (HCA) in 91 (37%); 42% of the latter were nursing home residents, in whom OXA-48-producing K. pneumoniae ST405 predominated. MBLs and OXA-48 predominated in ICU and medical patients, respectively. Overall, 67% of patients had infections. The most frequent infections identified in this study were urinary tract (43%) and skin structure (21%) infections, and 10% of infections were bacteraemic. Crude mortality was 20%. Inappropriate antibiotic therapy was independently associated with an increased risk of death (OR = 3.30; 95% CI: 1.34–8.11). Conclusions We found some differences in the epidemiology of CPE depending on the type of carbapenemase produced. Although a low proportion of CPE infections were bacteraemic, active antibiotic therapy was a protective factor for reducing mortality.

In this paper, are presented the characterization of two force sensors, in bias to incorporate them to the fingers of a robotic hand. The main goal of this work is to determine as main characteristic, the response of each sensor, in order to decide, which of them is the most effective for manipulation tasks in a mobile robotic platform. Manipulation mobile robot tasks, require to adapt its behavior and fingers configuration depending of the type and form of diverse objects. The first evaluated sensor is a cheap resistive force sensor and second is a piezoelectric force sensor. As robotic hand and then sensors will be incorporate on a mobile platform, sensor signals are sent to the a computer through a data card acquisition; an Arduino card has been used. We show the evaluation, results and conclusions of the experiments done.

Se registran por primera vez para México a Meruliporia incrassata, Physisporinus rivulosus, Pycnoporellus alboluteus y Skeletocutis alutacea, y se amplía la distribución conocida de Fibroporia vaillantii para el Estado de México. Estas especies ocasionan pudrición blanca o marrón en madera de Abies religiosa. Los ejemplares estudiados se recolectaron en los estados de México y Tlaxcala y están depositados en los herbarios ENCB y TLXM.

Continuous and short-term disturbances are produced on intertidal Brachidontes rodriguezii mussel beds by the sewage outfall of Mar del Plata, SW Atlantic. The effects on the associated polychaetes living on and between mussels were investigated, in both the spatial and short-term temporal scales. Multivariate methods show that the polychaete fauna was influenced by tidal level, total amount of sediment accumulated between mussels, distance from the sewage outfall, organic carbon of interstitial sediments, and sewage volume before and after the summer season. Environmental variables in the water column fitted with a spatial and temporal organic gradient. Capitella ‘capitata’ sp. showed typical opportunistic behaviour in relation to organic enrichment, as did Neanthes succinea , both being numerically dominant near the sewage discharge. Cirratulus sp., Caulleriella alata , and Boccardia polybranchia were common at intermediate distances from the outfall. Syllis prolixa, S. gracilis , and Protoariciella uncinata reached their highest abundance at intermediate stations and were characteristic of the control site. Close to the outfall mussel density and dominance is low, and opportunist polychaetes successfully colonize organically enriched interstitial sediments. At intermediate distances from the outfall sediments retained by mussels reach their maximum values, and density of polychaetes is also high. The control station is characterized by monolayered mussel beds and very low diversity of polychaetes. Opportunistic polychaetes increase in response to short-term increases of sewage discharge during the summer season (November-March).

Continuous and short-term disturbances are produced on intertidal Brachidontes rodriguezii mussel beds by the sewage outfall of Mar del Plata, SW Atlantic. The effects on the associated polychaetes living on and between mussels were investigated, in both the spatial and short-term temporal scales. Multivariate methods show that the polychaete fauna was influenced by tidal level, total amount of sediment accumulated between mussels, distance from the sewage outfall, organic carbon of interstitial sediments, and sewage volume before and after the summer season. Environmental variables in the water column fitted with a spatial and temporal organic gradient. Capitella ‘capitata’ sp. showed typical opportunistic behaviour in relation to organic enrichment, as did Neanthes succinea, both being numerically dominant near the sewage discharge. Cirratulus sp., Caulleriella alata, and Boccardia polybranchia were common at intermediate distances from the outfall. Syllis prolixa, S. gracilis, and Protoariciella uncinata reached their highest abundance at intermediate stations and were characteristic of the control site. Close to the outfall mussel density and dominance is low, and opportunist polychaetes successfully colonize organically enriched interstitial sediments. At intermediate distances from the outfall sediments retained by mussels reach their maximum values, and density of polychaetes is also high. The control station is characterized by monolayered mussel beds and very low diversity of polychaetes. Opportunistic polychaetes increase in response to short-term increases of sewage discharge during the summer season (November-March). Perturbaciones contínuas y de corto período de tiempo debidas a efluentes domésticos afectan a los bancos de los bivalvos Brachidontes rodriguezii en Mar del Plata, Atlántico sudoccidental. Se investigaron sus efectos sobre los poliquetos que viven asociados dentro y sobre los bancos, tanto en la escala espacial como la temporal (corto plazo). Métodos multivariados mostraron que los poliquetos estuvieron relacionados al nivel de marea, al total de sedimentos acumulados entre los bivalvos, a la distancia al efluente, al carbono orgánico total de los sedimentos y al volumen de descarga antes y después del verano. Las variables ambientales de la columna de agua estuvieron en concordancia con un gradiente de enriquecimiento orgánico espacial y temporal. Capitella ‘capitata’ sp. mostró el típico comportamiento oportunista en relación al enriquecimiento orgánico, al igual que Neanthes succinea, siendo ambas especies numéricamente dominantes cerca del efluente. Cirratulus sp., Caulleriella alata y Boccardia polybranchia fueron comunes a distancias intermedias del efluente. Syllis prolixa, S. gracilis y Protoariciella uncinata alcanzaron sus más altas abundancias a distancias intermedias, pero fueron características del sitio control. Cerca de la descarga del efluente la densidad y dominancia de bivalvos es baja, y los poliquetos oportunistas colonizaron exitosamente los sedimentos intersticiales enriquecidos orgánicamente. A distancias intermedias del efluente los sedimentos retenidos por los bivalvos alcanzaron sus mayores valores, y la riqueza de los poliquetos fue también alta. Las áreas control estuvieron caracterizadas por una monocapa de bivalvos y muy baja riqueza de poliquetos. Los poliquetos oportunistas incrementaron sus abundancias en respuesta al incremento del volumen de descarga en el período antes-después del verano (noviembre-marzo). &nbsp

En el presente trabajo se redescriben 11 especies de hongos poliporoides poco conocidas para México; de las cuales 10 especies ya habían sido citadas para el país, pero no se describieron morfológicamente. Entre ellas tenemos a Fistulina hepatica Shaeffer :Fr., Bjerkandera fumosa (Pers. :Fr.) Karsten, Ceriporia excelsaLundell) Parmasto, C. xylostromatoides (Berkeley) Ryvarden et Johansen, Oxyporus populinus (Schum. :Fr.) Donk, Perenniporia tenuis (Schweinitz), Skeletocutis ochroalba Niemelä, Spongipellisunicolor (Schweinitz) Murrill, Ryvarden, Sistotrema confluens Pers. :Fr. y Junghuhnia semisupiniforme (Murrill) Ryvarden. Además, Oligoporus hibernicus (Berkeley et Broome) Gilbertson et Ryvarden, se presenta como nuevo registro para México.We describe 11 species of little known poliporoid fungi from Mexico, of which ten species have been cited from this country, but morphological descriptions have not been presented. The species are Fistulina hepatica Shaeffer: Fr., Bjerkandera fumosa (Pers. :Fr.) Karsten, Ceriporia excelsa (Lundell) Parmasto, Ceriporia xylostromatoides (Berkeley) Ryvarden & Johansen, Oxyporus populinus (Schum.: Fr. Donk), Perenniporia tenuis (Schweinitz) Ryvarden, Skeletocutis ochroalba Niemelä, Spongipellis unicolor (Schweinitz) Murrill, Sistotrema confluens Pers.: Fr. and Junghuhnia semisupiniforme (Murrill) Ryvarden. In addition, Oligoporus hibernicus (Berkeley & Broome) Gilbertson & Ryvarden represents new record from Mexico.

The “rave” phenomenon has been a major element in the resurgence of psychedelic drug use in Western society. Purportedly central to raves is the use of “club drugs,” such as 3,4-methylenedioxymetha...

Paleorecords from multiple indicators of environmental change provide evidence for the interactions between climate, human alteration of watersheds and lake ecosystem processes at Lake Tanganyika, Africa, a lake renowned for its extraordinary biodiversity, endemism and fisheries. This paper synthesizes geochronology, sedimentology, paleoecology, geochemistry and hydrology studies comparing the history of deltaic deposits from watersheds of various sizes and deforestation disturbance levels along the eastern coast of the lake in Tanzania and Burundi. Intersite differences are related to climate change, differences in the histories of forested vs. deforested watersheds, differences related to regional patterns of deforestation, and differences related to interactions of deforestation and climate effects. Climate change is linked to variations in sediment accumulation rates, charcoal accumulation, lake level and water chemistry, especially during the arid-humid fluctuations of the latter part of the Little Ice Age. Differences between forested and deforested watersheds are manifested by major increases in sediment accumulation rates in the latter (outside the range of climatically driven variability and for the last ∼40 years unprecedented in comparison with other records from the lake in the late Holocene), differences in eroded sediment and watershed stream composition, and compositional or diversity trends in lake faunal communities related to sediment inundation. Variability in regional patterns of deforestation is illustrated by the timing of transitions from numerous sedimentologic, paleoecologic and geochemical indicators. These data suggest that extensive watershed deforestation occurred as early as the late-18th to the early-19th centuries in the northern part of the Lake Tanganyika catchment, in the late-19th to early-20th centuries in the northern parts of modern-day Tanzania, and in the mid-20th century in central Tanzania. Rapid increases in sediment and charcoal accumulation rates, palynological and lake faunal changes occurred in the early-1960s. We interpret this to be the result of greatly enhanced flushing of sediments in previously deforested watersheds triggered by extraordinary rainfall in 1961/62. Regional differences in deforestation histories can be understood in light of the very different cultural and demographic histories of the northern and central parts of the lake shoreline. Incursion of slaving and ivory caravans from the Indian Ocean to the central coast of Lake Tanganyika by the early-19th century, with their attendant diseases, reduced human and elephant populations and therefore maintained forest cover in this region through the late-19th to early-20th centuries. In contrast, the northeastern portion of the lakeshore did not experience the effects of the caravan trades and consequently experienced high human population densities and widespread deforestation much earlier. These studies demonstrate the importance of paleolimnological data for making informed risk assessments of the potential effects of watershed deforestation on long-term lake ecosystem response in the Lake Tanganyika catchment. Differences in sediment yield and lake floor distribution of that yield, linked to factors such as watershed size, slope, and sediment retention, must be accounted for in management plans for both human occupation of currently forested watersheds and the development of future underwater reserves.

Fossil invertebrates from cores collected in Lake Tanganyika provide a record of probable nearshore ecological response to recent watershed deforestation and sediment erosion in several East African watersheds. We compared paleoecological profiles (primarily from ostracodes) from watersheds spanning a range of sizes and present-day deforestation disturbance levels to understand the timing and magnitude of faunal changes, and their relationship in time to terrestrially-derived disturbance indicators. Profiles from the Lubulungu and Nyasanga/Kahama Rivers (Tanzania) provide a record of faunal variability in watersheds that are currently undisturbed with respect to deforestation. These records indicate continuous faunal turnover through time. However, this pattern of turnover is accompanied by relatively high levels of diversity throughout the record, with no wholesale extinction events. Ostracode taphonomic data and other fossil abundance data from the Lubulungu area provide strong evidence in support of at least two episodes of lower lake levels, associated with episodes of Late Holocene aridity. Records from deltas of disturbed watersheds at the Kabesi River (Tanzania) and those of Northern Burundi all show a combination of profound and abrupt faunal turnover, in some cases accompanied by local extinction and establishment of a few dominant taxa. At the Mwamgongo River delta, fed from a very small, disturbed watershed, species turnover was subtler. In disturbed watershed cores showing abrupt faunal changes the transitions mostly occurred in the late 19th to early 20th centuries, predating the major mid-20th century increase in sediment mass accumulation rates, with the latter only correlated with changing fossil abundance and flux. However, the earlier faunal community changes are contemporaneous with both palynological and geochemical changes in the core profiles indicative of changing land-use patterns. This suggests that lacustrine ecosystem response to deforestation was a two-stage process, with an earlier phase of response to changing quality of sediments or dissolved matter being discharged from the watershed, and a subsequent phase responding to increased quantity of sediment.

Evaporation dominates the removal of water from Lake Tanganyika, and therefore the oxygen isotope composition of lake water has become very positive in comparison to the waters entering the lake. The surface water in Lake Tanganyika has remained relatively unchanged over the last 30 years with a seasonal range of +3.2 to +3.5‰ VSMOW. Water from small rivers entering the lake seems to have a δ18O value between −3.5 and −4.0‰, based on scattered measurements. The two largest catchments emptying into the lake deliver water that has a δ18O value between these two extremes. This large contrast is the basis of a model presented here that attempts to reconstruct the history of runoff intensity based on the δ18O of carbonate shells from Lake Tanganyika cores. In order to use biogenic carbonates to monitor changes in the δ18O of mixing-zone water, however, the oxygen isotope fractionation between water and shell carbonate must be well understood. The relatively invariant environmental conditions of the lake allow us to constrain the fractionation of both oxygen and carbon isotope ratios. Although molluskan aragonitic shell δ18O values are in agreement with published mineral-water fractionations, ostracode calcite is ∼1.2‰ more positive than that of inorganic calcite precipitated under similar conditions. Ostracode shell δ18O data from two cores from central Lake Tanganyika suggest that runoff decreased in the first half of this millennium and has increased in the last century. This conclusion is poorly constrained, however, and much more work needs to be done on stable isotope variation in both the waters and carbonates of Lake Tanganyika. We also compared the δ13C of shells against predicted values based solely on the δ13C of lake water dissolved inorganic carbon (DIC). The ostracode Mecynocypria opaca is the only ostracode or mollusk that falls within the predicted range. This suggests that M. opaca has potential for reconstructing the carbon isotope ratio of DIC in Lake Tanganyika, and may be a useful tool in the study of the history of the lake’s productivity and carbon cycle.

We investigated paleolimnological records from a series of river deltas around the northeastern rim of Lake Tanganyika, East Africa (Tanzania and Burundi) in order to understand the history of anthropogenic activity in the lake’s catchment over the last several centuries, and to determine the impact of these activities on the biodiversity of littoral and sublittoral lake communities. Sediment pollution caused by increased rates of soil erosion in deforested watersheds has caused significant changes in aquatic communities along much of the lake’s shoreline. We analyzed the effects of sediment discharge on biodiversity around six deltas or delta complexes on the east coast of Lake Tanganyika: the Lubulungu River delta, Kabesi River delta, Nyasanga/Kahama River deltas, and Mwamgongo River delta in Tanzania; and the Nyamuseni River delta and Karonge/Kirasa River deltas in Burundi. Collectively, these deltas and their associated rivers were chosen to represent a spectrum of drainage-basin sizes and disturbance levels. By comparing deltas that are similar in watershed attributes (other than disturbance levels), our goal was to explore a series of historical ‘‘experiments’’ at the watershed scale, with which we could more clearly evaluate hypotheses of land use or other effects on nearshore ecosystems. Here we discuss these deltas, their geologic and physiographic characteristics, and the field procedures used for coring and sampling the deltas, and various indicators of anthropogenic impact.

Documenting the history of catchment deforestation using paleolimnological data involves understanding both the timing and magnitude of change in the input of erosional products to the downstream lake. These products include both physically-eroded soil and the byproducts of burning, primarily charcoal, which arise from both intentional and climatically-induced changes in fire frequency. As a part of the Lake Tanganyika Biodiversity Project’s special study on sedimentation, we have investigated the sedimentological composition of seven dated cores from six deltas or delta complexes along the east coast of Lake Tanganyika: the Lubulungu River delta, the Kabesi River delta, the Nyasanga/Kahama River delta, and the Mwamgongo River delta in Tanzania, and the Nyamusenyi River delta and Karonge/Kirasa River delta in Burundi. Changes in sediment mass accumulation rates, composition, and charcoal flux in the littoral and sublittoral zones of the lake that can be linked to watershed disturbance factors in the deltas were examined. Total organic carbon accumulation rates, in particular, are strongly linked to higher sediment mass accumulation from terrestrial sources, and show striking mid-20th century increases at disturbed watershed deltas that may indicate a connection between increased watershed erosion and increased nearshore productivity. However, changes in sedimentation patterns are not solely correlated with the 20th century period of increasing human population in the basin. Fire activity, as recorded by charcoal accumulation rates, was also elevated during arid intervals of the 13th–early 19th centuries. Some differences between northern and southern sedimentation histories appear to be correlated with different histories of human population in central Tanzania in contrast with northern Tanzania and Burundi.

We established sediment geochronologies for cores from eight deltaic areas in Lake Tanganyika (the Lubulungu, Kabesi, Halembe, Malagarasi, Nyasanga/Kahama, Mwamgongo, Nyamusenyi, and Karonge/Kirasa River deltas), recording a range of watershed disturbance histories from the eastern margin of this African rift valley lake. Cores from currently disturbed sites on the central Tanzanian coast display remarkably uniform and low rates of sediment accumulation from the 18th century until the early 1960s, when a synchronous and dramatic rise in rates occurs. Through this same time interval sedimentation rates offshore from undisturbed Tanzanian watersheds either remain unchanged or decline. Further north, at disturbed sites along the northern Tanzania and Burundi coasts, the pattern of sedimentation rate increase is more complex. Although a mid-late 20th century increase is also evident in these sites, indications of earlier periods of increasing sediment erosion, dating from the mid-late 19th century, are also evident. Synchronous changes in sediment accumulation rates dating from the early 1960s may be the result of exceptionally wet years triggering an increase in the discharge of previously eroded and unconsolidated alluvium and stream/beach terrace deposits, previously accumulated in the deltas and stream valleys of impacted watersheds. Sedimentation rate impacts of deforestation on lake ecosystems are likely modulated by short-term climatic forcing events, which can impact the specific timing and location of sediment discharge to lakes.

This work describes short-term responses of sandy-bottom infaunal macrobenthic communities to environmental disturbances, such as episodic storms and the intertidal sewage discharge of the Mar del Plata City (38° S, 57° W, Argentina). Sewage discharge increases by up to 60% every summer due to tourism pressure. Episodic storms affect the area during autumn-winter and arguably have a cleaning effect on the water and sediment quality. Quantitative data on benthic communities (based on Van Veen grab samples), water and sediment variables were obtained in November 1999 and March 2000. During March the sampling was carried out before and after a storm. Parametric and non- parametric tests showed highly significant differences in both environmental (pH, dissolved oxygen, salinity, temperature, grain size and total organic carbon of sediments) and biological data (species distribution and abundances, density, species number, diversity and evenness), reflecting changes that might be related to increasing sewage discharge between November and March, and to storm effects of March. High values of pH and dissolved oxygen, including a slight stratification in the water column, as well as high values of mean grain size and total organic carbon were observed in March with the increasing sewage volume. Nevertheless, diversity and evenness showed low values, but higher density. The ratio crustacean/polychaetes + molluscs also showed low values compared to November data. Maldanid polychaetes (indicator of low content of organic matter in sediments) dominated in November, but they were replaced by the polychaete Prionospio spp. (indicator of organic enrichment in subtidal areas) and the tanaidacean Kalliapseudes schubarti in March. Before the storm event, values of both environmental and biological data returned to relatively normal conditions, but without reaching the November values, reflecting the disturbance produced by a moderate northern storm. In spite of an inappropriate replication in time, the present results strongly suggest that these changes were related to both sewage disturbance and storm effects. These data are in agreement with and explain the pattern observed in shallow-shelf benthic communities of the SW Atlantic. Implications for environmental management and decision making are discussed, because a pulse disturbance (storms) becomes a press disturbance, keeping the environment healthy in spite of strong pressure and pulse sewage-disturbances.

Concentrated starch gels were supplemented with four alpha-amylases from different sources. The retrogradation and recrystallization of the gels were evaluated using differential scanning calorimetry (DSC) and X-ray crystallography. Correlations between the retrogradation data and the carbohydrate fractions extracted from these gels were determined. The thermostable (TBA) and intermediate temperature stability (ISBA) bacterial alpha-amylases were most effective in decreasing the rate of retrogradation of the starch in the gels. The cereal alpha-amylase at the high level (CAH) was also effective. Supplementation with the alpha-amylases increased the crystallinity of the gels. Gels supplemented with TBA or ISBA were most crystalline and retrograded to a lesser extent. The results indicated that DSC gives not only a measure of recrystallized amylopectin but also a measure of total order (recrystallized amylopectin and double-helical content). The maltooligosaccharides produced by the enzymes did not appear to be responsible for the reduced rates of retrogradation, but they appeared to be an expression of the degree of starch modification that was responsible for the inhibition of retrogradation. The crystallinity and retrogradation data were similar to results reported for bread and strongly suggest that bread staling is caused by the retrogradation of starch. The results also indicate that alpha-amylases decrease the rate and extent of retrogradation of starch gels by inhibiting the formation of double helices.

The firming and carbohydrate fractions of concentrated starch gels supplemented with four alpha-amylases from different sources were evaluated. Correlations were found between the firmness data and results for the carbohydrate fractions extracted from the gels. The thermostable (TBA) and intermediate temperature stability (ISBA) bacterial alpha-amylases were most effective in decreasing the rate of firming. The cereal alpha-amylase at the high level (CAH) was also effective. The CAH produced the largest quantity of dextrins at storage time zero and the thermostable bacterial alpha-amylase at the high level (TBAH) after storage for 5 days. None of the maltooligosaccharides appeared to be responsible for the decreased rate of firming of the gels. The results indicated that the TBA and ISBA most effectively inhibited firming because they degraded the external branches and the intercluster regions of amylopectin during storage. Consideration of previously reported differential scanning calorimetry and X-ray crystallography results leads to the conclusion that the antifirming action of the TBA and ISBA is due to their ability to degrade the amylopectin and amorphous regions of the gels during storage, which inhibits the formation of double helices and decreases the strength of the starch gel matrix. Gels supplemented with the TBA and ISBA were most crystalline but firmed to a lesser extent. These results are similar to those previously reported by other researchers for bread and strongly suggest that starch retrogradation plays a primary role in bread staling.

Background: Meat allergy is rarely reported. Most of the described cases are sensitizations to bovine serum albumin. Objective: The aim of the study was to describe a case of allergy to a new meat allergen and, after its characterization. Methods: A 35-year-old nonatopic female with allergic episodes after ingestion of several types of meat was studied. Skin tests (prick and prick-to-prick); total and specific immunoglobulin E (IgE) determination; sodium dodecyl sulphate-polyacrylamide gel electrophoresis and specific IgE determination by immunoblotting under different conditions were performed. A 17-kDa allergen was semipurified by ethanol fractionation and its amino-terminal sequence was determined. The existence of specific IgE directed to this protein was studied by immunoblot in 80 atopic patients. Results: The patient showed specific IgE antibodies to a 17-kDa protein. During the isolation of this allergen it was found that a 70–90% (vol/vol) ethanol concentration was able to purify the protein. The characterization revealed that it was a heat-resistant protein without disulfide bonds. N-terminal amino acid sequence (16 residues) showed identity with myoglobin. The study of specific IgE to this allergen among atopic patients showed that it was recognized by about 1% of the subjects. Conclusions: We describe a case of meat allergy caused by myoglobin. This is the first described case of monosensitization to this protein.

Twenty-eight (11.6%) out of 241 Spanish patients enrolled in an international phase III clinical trial of mild to moderate community-acquired pneumonia (CAP) comparing gemifloxacin vs. trovafloxacin were diagnosed of Legionnaires' disease. A definite diagnosis was established by seroconversion in 13 patients of whom only 2 had a positive Legionella urinary antigen. The remaining 15 patients were possible Legionella infections based on a single elevated IgG titer (> or = 1:512). All patients had a radiologically confirmed diagnosis of pneumonia, 5 (19%) patients were older than 65, comorbidity was present in 9 (33%), and 10 (36%) had to be hospitalized. Fifteen patients were treated with oral gemifloxacin (320 mg/day) and 13 with oral trovafloxacin (200 mg/day). Overall, clinical success occurred in 25 (89.3%) patients after 7 days of treatment and only 1 patient needed a 14-day treatment. There were only one adverse event withdrawal and one clinical failure, and no patients died. In light of the favorable clinical outcome, the use of newer fluoroquinolones seems adequate for the treatment of suspected or proven Legionella pneumonia.

Ostracodes are microcrustaceans that inhabit almost any aquatic system. Over the past 12 years, these microcrustaceans have provided valuable information about the hydraulics and chemistry of aquatic systems related to human activity (e.g., irrigation canals, reservoirs) in southwestern North America. This study synthesizes the results obtained in the last decade and suggests how ostracodes may be used in other regions around the world. RESUMEN Los ostrdcodos son microcrustdceos que habitan casi cualquier ambiente acudtico. Durante los 'ltimos 12 aios, estos organismos han proporcionado valiosa informaci6n sobre las caracteristicas hidrdulicas e hidrodindmicas de sistemas acudticos relacionados con actividades humanas (e.g., canales de irrigaci6n, aguajes) en el sudoeste norteamericano. Este trabajo sintetiza los resultados obtenidos durante la dltima dicada y sugiere c6mo podrian ser utilizados en otras regiones del mundo. Understanding environmental impact by humans in the past has generated a significant number of studies in geoarchaology. The focus of this study is to document some of the best examples of ostracodes (microcrustaceans) as a proxy measure of environmental impact on Precolumbian irrigation systems in the U.S. Southwest, mostly those built by the Hohokam (A.D. 100-A.D. 1450) and their ancestors, the Early Agriculturalists (1900 B.C.-A.D. 100).

Most of the macroinfauna from sandy beaches is highly mobile, emerging out of the sediment when the tide rises, and using the swash to migrate up and down the beach face or feed (searching for prey or carrion). After swash excursions, they usually burrow back into the sediment, maintaining zonation at low tide. Therefore, the different species abilities to emerge, move around and burrow under different swash climates and sediment conditions are expected to influence observed distribution patterns. Nonetheless, few attempts have been made to understand behavioral mechanisms of these organisms in moving fluids. In this study, we used a flume tunnel to investigate the orientation, swimming ability and burrowing time of two similar species of cirolanid isopods, Excirolana armata Dana and Excirolana braziliensis Richardson, under current velocities ranging from 5 to 30 cm·s −1 . E. armata inhabits middle levels of dissipative to intermediate beaches, while E. braziliensis is found towards the upper level of a wider range of beach states. Both species oriented countercurrent above a threshold velocity, which turned out to be significantly lower for E. armata than for E. braziliensis . E. armata proved to be a stronger swimmer as shown by the higher velocities surmounted, and the less drags experienced at the highest current velocity. E. armata also burrowed faster than E. braziliensis . Burrowing time was affected by sediment grain size and water content, but not by water flow. Once organisms managed to begin burrowing under different flow conditions, they were not affected by current velocity. Nonsaturated sand precluded burial, while coarse sand retarded it. Differences in the observed patterns of across-beach distribution may thus be the result of species-specific behavioral responses to swash climate, manifested in swimming ability, burying and orientation in directional flows.

Paleoecology of Laguna Babicora, Chihuahua, Mexico was reconstructed using ostracode faunal assemblages and shell chemistry. The paleolimnological record is used to show the magnitude of paleoclimatic changes in the area from 25,000 years to the present. Faunal assemblages consist of four species of the genus Limnocythere: L. sappaensis, L. ceriotuberosa, L. bradburyi and L. platyforma, all associated with Candona caudata, Candona patzcuaro and Cypridopsis vidua. A paleosalinity index developed from these assemblages indicates that the lake's salinity fluctuated frequently from oligo- to meso-haline conditions during the last ∽ 25,000 years. This pattern and low salinity range are in good agreement with modern TDS (here used as an indicator of salinity) values recorded from 26 wells and one spring from the area (258–975 mg l−1). To estimate paleotemperature we examined the trace element content (Mg/Ca ratios) from individual valves of L. ceriotuberosa and L. platyforma, the two species most commonly recorded in Laguna Babicora. Shell Mg/Ca ratios of 204 specimens of these two species were used to estimate water temperature (Mg/Ca) by means of experimental standard coefficients. Our data show that paleowater temperature ranged from 5.6–21.3 °C (with 2σ values ranging from 0.2–4.8 °C), which suggest a close correlation with atmospheric temperatures around the lake. These results are in good agreement with a modern mean winter temperature (3.5 °C) and mean summer temperature (20 °C) recorded in the area between 1970 and 1980.

In a study of the minor element chemistry of ostracode shells, Wansard and Mezquita (2001) concluded that the Mg/Ca and Sr/Ca of the ambient water controlled the respective ratios in ostracode calcite. Contrary to their conclusion that minor element chemistry is not influenced by temperature, we find a very strong statistical correlation (r = 0.97) between temperature and shell chemistry in their data. This discrepancy apparently arises due to their use of a partition coefficient model of shell chemistry that masks a number of strong correlations in their data. We argue here that the partition coefficient model is not appropriate for this biologically-mediated carbonate, and that a broader range of possible controls on shell chemistry needs to be tested.

For the first time, the Early Agricultural Period (1200 bc –150 ad ) canal irrigation in the Santa Cruz River Valley, southeastern Arizona, is documented through ostracode paleoecology. Interpretations based on ostracode paleoecology and taphonomy are supported by anthropological, sedimentological, geomorphological, and palynological information, and were used to determine the environmental history of the northern Tucson Basin during the time span represented by the sequence of canals at Las Capas (site AZ AA:12:753 ASM). We also attempt to elucidate based on archaeological artifacts if the Hohokam or a previous civilization built the canals. Between 3000 and 2400 radiocarbon years bp , at least three episodes of canal operation are defined by ostracode assemblages and pollen records. Modern (mid–late 20th century) canals supported no ostracodes, probably because of temporally brief canal operation from local wells. Three stages of water management are well defined during prehistoric canal operation. Ostracode faunal associations indicate that prehistoric peoples first operated their irrigation systems in a simple, ‘opportunistic’ mode (diversion of ephemeral flows following storms), and later in a complex, ‘functional’ mode (carefully timed diversions of perennial flows). The geomorphological reconstruction indicates that these canals had a minimum length of 1.1 km, and were possibly twice as long. The hydraulic reconstruction of these canals suggests that they had similar gradients (0.05–0.1%) to later prehistoric canals in the same valley. Discharges were also respectable. When flowing at bank-full, the largest canal provided an acre-foot of water in about 2.3 h; when flowing half-full (probably a more realistic assumption), it produced an acre-foot of water in about 8.6 h. Palynological records of the oldest canals (here identified as Features 3 and 4; 3000–2500 years bp ) indicate they were used temporarily, since riparian vegetation did not grow consistently in the area. The presence of maize (Zea sp.) pollen in the canals confirms agricultural use of the canal water. However, a low percentage of maize and weed pollen suggests limited agricultural activity in this location, consistent with the lithostratigraphy, granulometry, and ostracode paleoecology. Agricultural fields were probably located downstream of this site. Ostracode assemblages show patterns consistent with the opportunistic or functional water control method, hence proving their value as indicators of human activity and environmental change. The transition from opportunistic to functional modes of canal operation indicates the increasing complexity of the social structure in the Santa Cruz Valley during the San Pedro Phase (1200–800 bc ) of the Early Agricultural Period.

The molar Mg/Ca ratio was measured in live-collected ostracodes from a small dammed body of water in northern Mexico. The species Cypridopsis vidua was collected every month throughout 1990. Four to ten specimens were measured from each month’s collection. Monthly average Mg/Ca ratios range from 0.018 to 0.032 and are correlated with water temperature. An anomalously cool July is reflected in lower Mg/Ca ratios in that month’s collection. The Mg/Ca ratio responds to temperature in this way: T° = (Mg/Ca −0.0103)/0.00066. The rapid valve chemistry response to temperature change in the lake can occur because the life span of C. vidua is very short (∼30 d). The high variability in the data set shows that many measurements of single valves must be averaged to track temperature change, or that many valves must be combined. Valves must also be screened for incomplete calcification as Mg/Ca ratios are significantly higher in poorly calcified valves. If the Mg/Ca of valve is modeled as a temperature-dependant partition coefficient, the residuals on a linear regression are significantly larger. This implies that ostracode biology and temperature play a significant role in the elemental composition of the valve and that water chemistry is of minor importance.

Activity rhythms of two cirolanid isopods, Excirolana armata and Excirolana braziliensis, were studied based on both seasonal field observations and laboratory experiments, at an exposed microtidal sandy beach in Uruguay. The natural emergence patterns of both species were observed in the field for 1 year, twice in each season, and correlated to sea level, expected tidal cycles and diel cycles. Laboratory experiments were carried out in order to detect endogenous rhythms of activity and observe how emergence of both species was affected by changes in light and/or sediment thixotropy. We also compared behavioral strategies of sympatric species that occupy different beach levels. Sea level (and thus swash zone position) during field sampling did not follow expected tidal cycles for most sampling occasions. E. armata was observed in activity most of the time, but activity only correlated with sea level on three out of eight occasions, and only once was correlated to expected tidal cycle. Laboratory results showed that emergence under constant conditions was rare; changes in sediment thixotropy stimulated emergence, but the response was not cyclical; light had little effect on this response. On the other hand, E. braziliensis was fairly scarce in the water column, but swimming individuals were observed always during the night. They displayed an endogenous circadian activity pattern in the laboratory which augmented in response to changes in sediment thixotropy. The natural light/dark cycle modulated both spontaneous and response emergence by increasing day/night differences in activity. In this study E. armata, a midlittoral species more exposed to sea level variations, seemed to rely entirely on different physical and/or biological cues to trigger emergence at the appropriate time. E. braziliensis, found mostly in the upper intertidal zone, emerged in a circadian rhythm, which was stimulated by changes in sediment thixotropy and reinforced by light cycles. The results of this study led us to conclude that on microtidal, unpredictable beaches, local physical and biological factors can combine to determine different activity strategies in organisms from different intertidal levels.