Wetlands are ecosystems susceptible to anthropogenic impacts; analysis of the scientific publicat... more Wetlands are ecosystems susceptible to anthropogenic impacts; analysis of the scientific publications on these ecosystems can be used as a reference to inform research and conservation measures. This bibliometric analysis aimed to evaluate the temporal evolution of scientific publications and trends in research topics related to the wetlands of Ecuador, Peru, and Chile; this region includes an extended desertic region in the southern Pacific. A total of 405 articles published during the period from 2000 to 2019 were reviewed. The most frequent subject areas were 'birds' and 'other types of fauna' (20.7% and 19.8%, respectively); the diversity of publications was similar, but the proportions of the total subject areas for each country varied. The number of papers published per year was found to be increasing. The thematic areas related to these ecosystems that require strengthening in Ecuador, Peru and Chile are identified (e. g. 'remote sensing' in Peru, 'microscopic organisms' in Chile and Ecuador). Decision-makers should use this information to continue developing helpful conservation lines (for example, those related to ecosystem services) and promote less developed lines of research identified for each country.
Figure S3. American alligator (Alligator mississippiensis) landmark figures showing landmarks (nu... more Figure S3. American alligator (Alligator mississippiensis) landmark figures showing landmarks (numbered) and semi-landmark curves (red) for the (A) scapula, (B) humerus in cranial view, (C) humerus in medial view, (D) humerus in caudal view, (E) ilium, (F) femur in cranial view, and (G) femur in caudal view. Scale = 50 mm
Biological asymmetry is present in all bilaterally symmetric organisms as a result of normal deve... more Biological asymmetry is present in all bilaterally symmetric organisms as a result of normal developmental instability. However, fossilized organisms, which have undergone distortion due to burial, may have additional asymmetry as a result of taphonomic processes. To investigate this issue, we evaluated the magnitude of shape variation resulting from taphonomy on vertebrate bone using a novel application of fluctuating asymmetry. We quantified the amount of total variance attributed to asymmetry in a taphonomically distorted fossil taxon and compared it to that of three extant taxa. The fossil taxon had an average of 27% higher asymmetry than the extant taxa. In spite of the high amount of taphonomic input, the major axes of shape variation were not greatly altered by removal of the asymmetric component of shape variation. This presents the possibility that either underlying biologic trends drive the principal directions of shape change irrespective of asymmetric taphonomic distortion, or that the symmetric taphonomic component is large enough that removing only the asymmetric component is inadequate to restore fossil shape. Our study is the first to present quantitative data on the relative magnitude of taphonomic shape change and presents a new method to further explore how taphonomic processes impact our interpretation of the fossil record
Tracheobronchial injuries following blunt trauma have a low incidence due to the high mortality r... more Tracheobronchial injuries following blunt trauma have a low incidence due to the high mortality rate before reaching hospitals. This case report advocates for conservative management in a hemodynamic patient with a large longitudinal tracheal laceration with no signs of acute complication.
larvae, postlarvae, and their culture environment and from healthy and diseased juve-niles and br... more larvae, postlarvae, and their culture environment and from healthy and diseased juve-niles and broodstock. In Ecuador, the dominant bacterial flora associated with shrimp larvae showing symp-toms of zoea 2 syndrome, mysis mold syndrome, and bolitas syndrome has been determined. Strains werecharacterized by Biolog metabolic fingerprinting and identified by comparison to a database of 850
8103 Background: Monoclonal Gammopathy of Unknown Significance (MGUS) is characterized by the pre... more 8103 Background: Monoclonal Gammopathy of Unknown Significance (MGUS) is characterized by the presence of a monoclonal immunoglobulin in the serum or the urine with no evidence of hematologic malignancy. A possible relationship between MGUS and increased incidence of NHM has been suggested in Caucasian populations. However, data in African Americans with MGUS are lacking. Methods: Non-MGUS controls were selected randomly from patients who did not have a paraprotein detected on electrophoresis (NMGUS) and were matched 2-to-1 to MGUS cases. Descriptive statistics and comparisons are presented to compare MGUS and NMGUS groups. Results: 492 male patients with MGUS patients were matched with 984 male NMGUS patients. 451 patients had abnormal serum protein studies (91.6%) and 40 had light chain disease (8.4%). Median age at diagnosis of MGUS was 68 years (28-81). 144 MGUS patients (29.2%) and 296 NMGUS patients (30%) had 1 or more NHM. The median age of diagnosis of 1st NHM was 70 (25-94)...
La operación segura de sistemas eléctricos requiere que los Operadores, sobre los cuales recae es... more La operación segura de sistemas eléctricos requiere que los Operadores, sobre los cuales recae esta gran responsabilidad, reconozcan de forma permanente el estado en que se encuentra la red supervisada y dispongan de los recursos para identificar amenazas probables, que le permitan anticipar y reaccionar de manera segura frente a eventos fortuitos de consecuencias predecibles, como ocurren cuando hay la salida de equipos durante la operación. En el ámbito de la Consciencia Situacional se dispone de una metodología que adecuadamente integrada con herramientas como el Análisis de Contingencias, posibilitan capacidades avanzadas de supervisión. Esto solo es posible, si se desarrollan a cabalidad tres fases de implementación, que se proponen conceptualmente en este trabajo como son; Modelación – Sintonización y Personalización. Siendo la Personalización la extensión metodológica clave para el logro de la integración planteada en este trabajo basado en años de experiencia de los autores...
Understanding how selective forces influence patterns of symmetry remains an active area of resea... more Understanding how selective forces influence patterns of symmetry remains an active area of research in evolutionary biology. One hypothesis, which has received relatively little attention, suggests that the functional importance of morphological characters may influence patterns of symmetry. Specifically, it posits that for structures that display bilateral symmetry, those with greater functional importance should display lower levels of asymmetry. The aim of this study was to examine the patterns of fluctuating asymmetry (FA) present in the limb bones of freshwater turtles in the family Emydidae. Aquatic emydid turtles of the subfamily Deirochelyinae employ a hindlimb-dominant swimming style, suggesting that hindlimbs should display lower levels of FA. Consistent with the morpho-functional hypothesis of symmetry, we found a strong, clade-wise pattern of humeral-biased FA in aquatic Deirochelyinae. In contrast, some emydids of the subfamily Emydinae possess more terrestrial tendencies. As terrestrial locomotion places more equal importance on fore-and hindlimbs, we predicted that such behaviors may minimize differences in FA. No clade-wise pattern was detected in the subfamily Emydinae. We also detected a phylogenetic signal in FA within the femur and discovered that FA has evolved at vastly different rates between the fore-and hindlimbs.
It has been hypothesized that fluctuating asymmetry (FA) may provide an indication of the functio... more It has been hypothesized that fluctuating asymmetry (FA) may provide an indication of the functional importance of structures within an organism, with structures that more strongly impact fitness being more symmetric. Based on this idea, we predicted that for tetrapods in which the forelimbs and hindlimbs play an unequal role in locomotion, the less functionally important limb set should display higher levels of FA. We conducted a multispecies test of this hypothesis in anurans (frogs and toads), whose saltatory locomotor mode is powered by the hindlimbs. We also tested whether FA in the forelimbs, which play a more important role during landing, differed between families that differ in the degree of forelimb use in locomotion (Bufonidae vs. Ranidae). We calculated FA from the lengths of humeri and femora measured from disarticulated skeletal specimens of four anuran taxa (Bufonidae: Anaxyrus americanus, Rhinella marina; Ranidae: Lithobates catesbeianus, Lithobates clamitans). Our findings were consistent with the hypothesis that natural selection for increased locomotor performance may influence patterns of FA seen in vertebrate limbs, with all species displaying lower mean FA in the hindlimbs. More subtle functional roles between the forelimbs of bufonids and ranids, however, did not elicit different levels of FA.
Synopsis Though ultimately descended from terrestrial amniotes, turtles have deep roots as an aqu... more Synopsis Though ultimately descended from terrestrial amniotes, turtles have deep roots as an aquatic lineage and are quite diverse in the extent of their aquatic specializations. Many taxa can be viewed as ''on the fence'' between aquatic and terrestrial realms, whereas others have independently hyperspecialized and moved ''all in'' to aquatic habitats. Such differences in specialization are reflected strongly in the locomotor system. We have conducted several studies to evaluate the performance consequences of such variation in design, as well as the mechanisms through which specialization for aquatic locomotion is facilitated in turtles. One path to aquatic hyperspecialization has involved the evolutionary transformation of the forelimbs from rowing, tubular limbs with distal paddles into flapping, flattened flippers, as in sea turtles. Prior to the advent of any hydrodynamic advantages, the evolution of such flippers may have been enabled by a reduction in twisting loads on proximal limb bones that accompanied swimming in rowing ancestors, facilitating a shift from tubular to flattened limbs. Moreover, the control of flapping movements appears related primarily to shifts in the activity of a single forelimb muscle, the deltoid. Despite some performance advantages, flapping may entail a locomotor cost in terms of decreased locomotor stability. However, other morphological specializations among rowing species may enhance swimming stability. For example, among highly aquatic pleurodiran turtles, fusion of the pelvis to the shell appears to dramatically reduce motions of the pelvis compared to freshwater cryptodiran species. This could contribute to advantageous increases in aquatic stability among predominantly aquatic pleurodires. Thus, even within the potential constraints of a body plan in which the body is encased by a shell, turtles exhibit diverse locomotor capacities that have enabled diversification into a wide range of aquatic habitats.
Identification of driver mutations in adenocarcinoma of the lung has revolutionized the treatment... more Identification of driver mutations in adenocarcinoma of the lung has revolutionized the treatment of this disease. It is now standard of care to look for activating mutations in epidermal growth factor receptor (EGFR), and translocations in anaplastic lymphoma kinase (ALK) or ROS1 in all newly diagnosed adenocarcinoma of the lung, and in many patients with squamous cell carcinoma as well. Recognition of multiple other lung cancer driver mutations has also expanded treatment options. Targeted treatments of these mutations lead to rapid and prolonged responses, but resistance inevitably develops. Until recently, traditional chemotherapy was the only alternative at that time, but better understanding of resistance mechanisms has lead to additional therapeutic options. These mechanisms of resistance and treatments are the focus of this chapter. Understanding of mechanisms of chemotherapy resistance is touched upon, along with a brief discussion of immune checkpoint inhibitors.
NeuroVault.org is dedicated to storing outputs of analyses in the form of statistical maps, parce... more NeuroVault.org is dedicated to storing outputs of analyses in the form of statistical maps, parcellations and atlases, a unique strategy that contrasts with most neuroimaging repositories that store raw acquisition data or stereotaxic coordinates. Such maps are indispensable for performing meta-analyses, validating novel methodology, and deciding on precise outlines for regions of interest (ROIs). NeuroVault is open to maps derived from both healthy and clinical populations, as well as from various imaging modalities (sMRI, fMRI, EEG, MEG, PET, etc.). The repository uses modern web technologies such as interactive web-based visualization, cognitive decoding, and comparison with other maps to provide researchers with efficient, intuitive tools to improve the understanding of their results. Each dataset and map is assigned a permanent Universal Resource Locator (URL), and all of the data is accessible through a REST Application Programming Interface (API). Additionally, the repository...
Patients with acquired resistance to first-generation EGFR TKIs, including those with the T790M m... more Patients with acquired resistance to first-generation EGFR TKIs, including those with the T790M mutation, may still respond to EGFR-targeted therapy. Combination afatinib and panitumumab may represent a viable therapeutic option for patients with acquired resistance to first-generation EGFR TKIs. Optimal management of LMC is an ongoing challenge, and the efficacy of targeted therapies remains undefined.
Here we present NeuroVault - a web based repository that allows researchers to store, share, visu... more Here we present NeuroVault - a web based repository that allows researchers to store, share, visualize, and decode statistical maps of the human brain. NeuroVault is easy to use and employs modern web technologies to provide informative visualization of data without the need to install additional software. In addition, it leverages the power of the Neurosynth database to provide cognitive decoding of deposited maps. The data are exposed through a public REST API enabling other services and tools to take advantage of it. NeuroVault is a new resource for researchers interested in conducting meta- and coactivation analyses.
Proceedings of the 1999 ACM/IEEE conference on Supercomputing, 1999
Compiler transformations can significantly improve data locality of scientific programs. In this ... more Compiler transformations can significantly improve data locality of scientific programs. In this paper, we examine the impact of multi-level caches on data locality optimizations. We find nearly all the benefits can be achieved by simply targeting the L1 (primary) cache. Most locality transformations are unaffected because they improve reuse for all levels of the cache; however, some optimizations can be enhanced. Inter-variable padding can take advantage of modular arithmetic to eliminate conflict misses and preserve group reuse on multiple cache levels. Loop fusion can balance increasing group reuse for the L2 (secondary) cache at the expense of losing group reuse at the smaller L1 cache. Tiling for the L1 cache also exploits locality available in the L2 cache. Experiments show enhanced algorithms are able to reduce cache misses, but performance improvements are rarely significant. Our results indicate existing compiler optimizations are usually sufficient to achieve good performance for multi-level caches.
Proceedings of the ACM SIGPLAN 1998 conference on Programming language design and implementation, 1998
Many cache misses in scientific programs are due to conflicts caused by limited set associativity... more Many cache misses in scientific programs are due to conflicts caused by limited set associativity. We examine two compile-time data-layout transformations for eliminating conflict misses, concentrating on misses occuring on every loop iteration. Inter-variable padding adjusts variable base addresses, while intra-variable padding modifies array dimension sizes. Two levels of precision are evaluated. PADLITE only uses array and column dimension sizes, relying on assumptions about common array reference patterns. PAD analyzes programs, detecting conflict misses by linearizing array references and calculating conflict distances between uniformly-generated references. The Euclidean algorithm for computing the gcd of two numbers is used to predict conflicts between different array columns for linear algebra codes. Experiments on a range of programs indicate PADLITE can eliminate conflicts for benchmarks, but PAD is more effective over a range of cache and problem sizes. Padding reduces cache miss rates by 16% on average for a 16K direct-mapped cache. Execution times are reduced by 6% on average, with some SPEC95 programs improving up to 15%.
We describe two ongoing compiler projects for high performance architectures at the University of... more We describe two ongoing compiler projects for high performance architectures at the University of Maryland being developed us- ing the Stanford SUIF compiler infrastructure. First, we are in- vestigating the impact of compilation techniques for eliminat- ing synchronization overhead in compiler-parallelized programs running on software distributed-shared-memory (DSM) systems. Second, we are evaluating data layout transformations to im- prove cache performance on uniprocessors by eliminating conflict misses through inter- and intra-variable padding. Our optimiza- tions have been implemented in SUIF and tested on a number of programs. Preliminary results are encouraging.
A major focus of the field of organismal biology is to understand how morphology impacts performa... more A major focus of the field of organismal biology is to understand how morphology impacts performance. Although the functional implications of certain aspects of shape have been widely examined, the functional implications of a related parameter, symmetry, remain mostly unknown. We used finite-element models to examine the effects of turtle shell asymmetry on shell strength across three morphologically distinct emydid species. The goals of this study were to: 1) test the hypothesis that increased asymmetry (independent of differences in shape) is associated with increased stress levels for a given load, and thus with weaker shells, 2) ascertain how asymmetry and the position of load application interact to influence shell strength, and 3) determine how interspecific differences in shape influence the effect of asymmetry. We found that increased asymmetry does produce higher stresses for both midline and non-midline loads. Non-midline loads produce slightly larger and more variable stresses. Species-specific shell shape can mitigate the effects of asymmetry; stronger shapes are potentially more resistant to the negative effects of asymmetry. Our findings indicate that changes in asymmetry associated with relatively small changes in shape can have as much of an effect on stress incurred by the shell as the changes in shape themselves.
Although physical features of the environment are known to influence shape, to date, the effects ... more Although physical features of the environment are known to influence shape, to date, the effects of many environmental conditions on asymmetry remain unexamined. The present study aimed to examine the relationship between asymmetry and the fluid media (air versus water) that an organism inhabits and, subsequently, to use these findings to test a novel hypothesis that fluid environments can impose selective forces acting to constrain asymmetry to maintain or enhance biomechanical function. We examined carapace asymmetry in 114 species (69 aquatic and 45 terrestrial) from the chelonian superfamily Testudinoidea. The results obtained indicate that environment is correlated with the degree of asymmetry, but in different directions for the two clades that comprise the Testudinoidea. Within the Testuguria, aquatic turtles have lower levels of asymmetry than terrestrial turtles, which is consistent with our proposed biomechanical hypothesis. This pattern was not observed within the Emydidae, possibly due to the much shorter time that terrestrial taxa in this clade have existed. Nevertheless, the present study provides the first evidence for a relationship between fluid media and asymmetry in any taxonomic group.
Wetlands are ecosystems susceptible to anthropogenic impacts; analysis of the scientific publicat... more Wetlands are ecosystems susceptible to anthropogenic impacts; analysis of the scientific publications on these ecosystems can be used as a reference to inform research and conservation measures. This bibliometric analysis aimed to evaluate the temporal evolution of scientific publications and trends in research topics related to the wetlands of Ecuador, Peru, and Chile; this region includes an extended desertic region in the southern Pacific. A total of 405 articles published during the period from 2000 to 2019 were reviewed. The most frequent subject areas were 'birds' and 'other types of fauna' (20.7% and 19.8%, respectively); the diversity of publications was similar, but the proportions of the total subject areas for each country varied. The number of papers published per year was found to be increasing. The thematic areas related to these ecosystems that require strengthening in Ecuador, Peru and Chile are identified (e. g. 'remote sensing' in Peru, 'microscopic organisms' in Chile and Ecuador). Decision-makers should use this information to continue developing helpful conservation lines (for example, those related to ecosystem services) and promote less developed lines of research identified for each country.
Figure S3. American alligator (Alligator mississippiensis) landmark figures showing landmarks (nu... more Figure S3. American alligator (Alligator mississippiensis) landmark figures showing landmarks (numbered) and semi-landmark curves (red) for the (A) scapula, (B) humerus in cranial view, (C) humerus in medial view, (D) humerus in caudal view, (E) ilium, (F) femur in cranial view, and (G) femur in caudal view. Scale = 50 mm
Biological asymmetry is present in all bilaterally symmetric organisms as a result of normal deve... more Biological asymmetry is present in all bilaterally symmetric organisms as a result of normal developmental instability. However, fossilized organisms, which have undergone distortion due to burial, may have additional asymmetry as a result of taphonomic processes. To investigate this issue, we evaluated the magnitude of shape variation resulting from taphonomy on vertebrate bone using a novel application of fluctuating asymmetry. We quantified the amount of total variance attributed to asymmetry in a taphonomically distorted fossil taxon and compared it to that of three extant taxa. The fossil taxon had an average of 27% higher asymmetry than the extant taxa. In spite of the high amount of taphonomic input, the major axes of shape variation were not greatly altered by removal of the asymmetric component of shape variation. This presents the possibility that either underlying biologic trends drive the principal directions of shape change irrespective of asymmetric taphonomic distortion, or that the symmetric taphonomic component is large enough that removing only the asymmetric component is inadequate to restore fossil shape. Our study is the first to present quantitative data on the relative magnitude of taphonomic shape change and presents a new method to further explore how taphonomic processes impact our interpretation of the fossil record
Tracheobronchial injuries following blunt trauma have a low incidence due to the high mortality r... more Tracheobronchial injuries following blunt trauma have a low incidence due to the high mortality rate before reaching hospitals. This case report advocates for conservative management in a hemodynamic patient with a large longitudinal tracheal laceration with no signs of acute complication.
larvae, postlarvae, and their culture environment and from healthy and diseased juve-niles and br... more larvae, postlarvae, and their culture environment and from healthy and diseased juve-niles and broodstock. In Ecuador, the dominant bacterial flora associated with shrimp larvae showing symp-toms of zoea 2 syndrome, mysis mold syndrome, and bolitas syndrome has been determined. Strains werecharacterized by Biolog metabolic fingerprinting and identified by comparison to a database of 850
8103 Background: Monoclonal Gammopathy of Unknown Significance (MGUS) is characterized by the pre... more 8103 Background: Monoclonal Gammopathy of Unknown Significance (MGUS) is characterized by the presence of a monoclonal immunoglobulin in the serum or the urine with no evidence of hematologic malignancy. A possible relationship between MGUS and increased incidence of NHM has been suggested in Caucasian populations. However, data in African Americans with MGUS are lacking. Methods: Non-MGUS controls were selected randomly from patients who did not have a paraprotein detected on electrophoresis (NMGUS) and were matched 2-to-1 to MGUS cases. Descriptive statistics and comparisons are presented to compare MGUS and NMGUS groups. Results: 492 male patients with MGUS patients were matched with 984 male NMGUS patients. 451 patients had abnormal serum protein studies (91.6%) and 40 had light chain disease (8.4%). Median age at diagnosis of MGUS was 68 years (28-81). 144 MGUS patients (29.2%) and 296 NMGUS patients (30%) had 1 or more NHM. The median age of diagnosis of 1st NHM was 70 (25-94)...
La operación segura de sistemas eléctricos requiere que los Operadores, sobre los cuales recae es... more La operación segura de sistemas eléctricos requiere que los Operadores, sobre los cuales recae esta gran responsabilidad, reconozcan de forma permanente el estado en que se encuentra la red supervisada y dispongan de los recursos para identificar amenazas probables, que le permitan anticipar y reaccionar de manera segura frente a eventos fortuitos de consecuencias predecibles, como ocurren cuando hay la salida de equipos durante la operación. En el ámbito de la Consciencia Situacional se dispone de una metodología que adecuadamente integrada con herramientas como el Análisis de Contingencias, posibilitan capacidades avanzadas de supervisión. Esto solo es posible, si se desarrollan a cabalidad tres fases de implementación, que se proponen conceptualmente en este trabajo como son; Modelación – Sintonización y Personalización. Siendo la Personalización la extensión metodológica clave para el logro de la integración planteada en este trabajo basado en años de experiencia de los autores...
Understanding how selective forces influence patterns of symmetry remains an active area of resea... more Understanding how selective forces influence patterns of symmetry remains an active area of research in evolutionary biology. One hypothesis, which has received relatively little attention, suggests that the functional importance of morphological characters may influence patterns of symmetry. Specifically, it posits that for structures that display bilateral symmetry, those with greater functional importance should display lower levels of asymmetry. The aim of this study was to examine the patterns of fluctuating asymmetry (FA) present in the limb bones of freshwater turtles in the family Emydidae. Aquatic emydid turtles of the subfamily Deirochelyinae employ a hindlimb-dominant swimming style, suggesting that hindlimbs should display lower levels of FA. Consistent with the morpho-functional hypothesis of symmetry, we found a strong, clade-wise pattern of humeral-biased FA in aquatic Deirochelyinae. In contrast, some emydids of the subfamily Emydinae possess more terrestrial tendencies. As terrestrial locomotion places more equal importance on fore-and hindlimbs, we predicted that such behaviors may minimize differences in FA. No clade-wise pattern was detected in the subfamily Emydinae. We also detected a phylogenetic signal in FA within the femur and discovered that FA has evolved at vastly different rates between the fore-and hindlimbs.
It has been hypothesized that fluctuating asymmetry (FA) may provide an indication of the functio... more It has been hypothesized that fluctuating asymmetry (FA) may provide an indication of the functional importance of structures within an organism, with structures that more strongly impact fitness being more symmetric. Based on this idea, we predicted that for tetrapods in which the forelimbs and hindlimbs play an unequal role in locomotion, the less functionally important limb set should display higher levels of FA. We conducted a multispecies test of this hypothesis in anurans (frogs and toads), whose saltatory locomotor mode is powered by the hindlimbs. We also tested whether FA in the forelimbs, which play a more important role during landing, differed between families that differ in the degree of forelimb use in locomotion (Bufonidae vs. Ranidae). We calculated FA from the lengths of humeri and femora measured from disarticulated skeletal specimens of four anuran taxa (Bufonidae: Anaxyrus americanus, Rhinella marina; Ranidae: Lithobates catesbeianus, Lithobates clamitans). Our findings were consistent with the hypothesis that natural selection for increased locomotor performance may influence patterns of FA seen in vertebrate limbs, with all species displaying lower mean FA in the hindlimbs. More subtle functional roles between the forelimbs of bufonids and ranids, however, did not elicit different levels of FA.
Synopsis Though ultimately descended from terrestrial amniotes, turtles have deep roots as an aqu... more Synopsis Though ultimately descended from terrestrial amniotes, turtles have deep roots as an aquatic lineage and are quite diverse in the extent of their aquatic specializations. Many taxa can be viewed as ''on the fence'' between aquatic and terrestrial realms, whereas others have independently hyperspecialized and moved ''all in'' to aquatic habitats. Such differences in specialization are reflected strongly in the locomotor system. We have conducted several studies to evaluate the performance consequences of such variation in design, as well as the mechanisms through which specialization for aquatic locomotion is facilitated in turtles. One path to aquatic hyperspecialization has involved the evolutionary transformation of the forelimbs from rowing, tubular limbs with distal paddles into flapping, flattened flippers, as in sea turtles. Prior to the advent of any hydrodynamic advantages, the evolution of such flippers may have been enabled by a reduction in twisting loads on proximal limb bones that accompanied swimming in rowing ancestors, facilitating a shift from tubular to flattened limbs. Moreover, the control of flapping movements appears related primarily to shifts in the activity of a single forelimb muscle, the deltoid. Despite some performance advantages, flapping may entail a locomotor cost in terms of decreased locomotor stability. However, other morphological specializations among rowing species may enhance swimming stability. For example, among highly aquatic pleurodiran turtles, fusion of the pelvis to the shell appears to dramatically reduce motions of the pelvis compared to freshwater cryptodiran species. This could contribute to advantageous increases in aquatic stability among predominantly aquatic pleurodires. Thus, even within the potential constraints of a body plan in which the body is encased by a shell, turtles exhibit diverse locomotor capacities that have enabled diversification into a wide range of aquatic habitats.
Identification of driver mutations in adenocarcinoma of the lung has revolutionized the treatment... more Identification of driver mutations in adenocarcinoma of the lung has revolutionized the treatment of this disease. It is now standard of care to look for activating mutations in epidermal growth factor receptor (EGFR), and translocations in anaplastic lymphoma kinase (ALK) or ROS1 in all newly diagnosed adenocarcinoma of the lung, and in many patients with squamous cell carcinoma as well. Recognition of multiple other lung cancer driver mutations has also expanded treatment options. Targeted treatments of these mutations lead to rapid and prolonged responses, but resistance inevitably develops. Until recently, traditional chemotherapy was the only alternative at that time, but better understanding of resistance mechanisms has lead to additional therapeutic options. These mechanisms of resistance and treatments are the focus of this chapter. Understanding of mechanisms of chemotherapy resistance is touched upon, along with a brief discussion of immune checkpoint inhibitors.
NeuroVault.org is dedicated to storing outputs of analyses in the form of statistical maps, parce... more NeuroVault.org is dedicated to storing outputs of analyses in the form of statistical maps, parcellations and atlases, a unique strategy that contrasts with most neuroimaging repositories that store raw acquisition data or stereotaxic coordinates. Such maps are indispensable for performing meta-analyses, validating novel methodology, and deciding on precise outlines for regions of interest (ROIs). NeuroVault is open to maps derived from both healthy and clinical populations, as well as from various imaging modalities (sMRI, fMRI, EEG, MEG, PET, etc.). The repository uses modern web technologies such as interactive web-based visualization, cognitive decoding, and comparison with other maps to provide researchers with efficient, intuitive tools to improve the understanding of their results. Each dataset and map is assigned a permanent Universal Resource Locator (URL), and all of the data is accessible through a REST Application Programming Interface (API). Additionally, the repository...
Patients with acquired resistance to first-generation EGFR TKIs, including those with the T790M m... more Patients with acquired resistance to first-generation EGFR TKIs, including those with the T790M mutation, may still respond to EGFR-targeted therapy. Combination afatinib and panitumumab may represent a viable therapeutic option for patients with acquired resistance to first-generation EGFR TKIs. Optimal management of LMC is an ongoing challenge, and the efficacy of targeted therapies remains undefined.
Here we present NeuroVault - a web based repository that allows researchers to store, share, visu... more Here we present NeuroVault - a web based repository that allows researchers to store, share, visualize, and decode statistical maps of the human brain. NeuroVault is easy to use and employs modern web technologies to provide informative visualization of data without the need to install additional software. In addition, it leverages the power of the Neurosynth database to provide cognitive decoding of deposited maps. The data are exposed through a public REST API enabling other services and tools to take advantage of it. NeuroVault is a new resource for researchers interested in conducting meta- and coactivation analyses.
Proceedings of the 1999 ACM/IEEE conference on Supercomputing, 1999
Compiler transformations can significantly improve data locality of scientific programs. In this ... more Compiler transformations can significantly improve data locality of scientific programs. In this paper, we examine the impact of multi-level caches on data locality optimizations. We find nearly all the benefits can be achieved by simply targeting the L1 (primary) cache. Most locality transformations are unaffected because they improve reuse for all levels of the cache; however, some optimizations can be enhanced. Inter-variable padding can take advantage of modular arithmetic to eliminate conflict misses and preserve group reuse on multiple cache levels. Loop fusion can balance increasing group reuse for the L2 (secondary) cache at the expense of losing group reuse at the smaller L1 cache. Tiling for the L1 cache also exploits locality available in the L2 cache. Experiments show enhanced algorithms are able to reduce cache misses, but performance improvements are rarely significant. Our results indicate existing compiler optimizations are usually sufficient to achieve good performance for multi-level caches.
Proceedings of the ACM SIGPLAN 1998 conference on Programming language design and implementation, 1998
Many cache misses in scientific programs are due to conflicts caused by limited set associativity... more Many cache misses in scientific programs are due to conflicts caused by limited set associativity. We examine two compile-time data-layout transformations for eliminating conflict misses, concentrating on misses occuring on every loop iteration. Inter-variable padding adjusts variable base addresses, while intra-variable padding modifies array dimension sizes. Two levels of precision are evaluated. PADLITE only uses array and column dimension sizes, relying on assumptions about common array reference patterns. PAD analyzes programs, detecting conflict misses by linearizing array references and calculating conflict distances between uniformly-generated references. The Euclidean algorithm for computing the gcd of two numbers is used to predict conflicts between different array columns for linear algebra codes. Experiments on a range of programs indicate PADLITE can eliminate conflicts for benchmarks, but PAD is more effective over a range of cache and problem sizes. Padding reduces cache miss rates by 16% on average for a 16K direct-mapped cache. Execution times are reduced by 6% on average, with some SPEC95 programs improving up to 15%.
We describe two ongoing compiler projects for high performance architectures at the University of... more We describe two ongoing compiler projects for high performance architectures at the University of Maryland being developed us- ing the Stanford SUIF compiler infrastructure. First, we are in- vestigating the impact of compilation techniques for eliminat- ing synchronization overhead in compiler-parallelized programs running on software distributed-shared-memory (DSM) systems. Second, we are evaluating data layout transformations to im- prove cache performance on uniprocessors by eliminating conflict misses through inter- and intra-variable padding. Our optimiza- tions have been implemented in SUIF and tested on a number of programs. Preliminary results are encouraging.
A major focus of the field of organismal biology is to understand how morphology impacts performa... more A major focus of the field of organismal biology is to understand how morphology impacts performance. Although the functional implications of certain aspects of shape have been widely examined, the functional implications of a related parameter, symmetry, remain mostly unknown. We used finite-element models to examine the effects of turtle shell asymmetry on shell strength across three morphologically distinct emydid species. The goals of this study were to: 1) test the hypothesis that increased asymmetry (independent of differences in shape) is associated with increased stress levels for a given load, and thus with weaker shells, 2) ascertain how asymmetry and the position of load application interact to influence shell strength, and 3) determine how interspecific differences in shape influence the effect of asymmetry. We found that increased asymmetry does produce higher stresses for both midline and non-midline loads. Non-midline loads produce slightly larger and more variable stresses. Species-specific shell shape can mitigate the effects of asymmetry; stronger shapes are potentially more resistant to the negative effects of asymmetry. Our findings indicate that changes in asymmetry associated with relatively small changes in shape can have as much of an effect on stress incurred by the shell as the changes in shape themselves.
Although physical features of the environment are known to influence shape, to date, the effects ... more Although physical features of the environment are known to influence shape, to date, the effects of many environmental conditions on asymmetry remain unexamined. The present study aimed to examine the relationship between asymmetry and the fluid media (air versus water) that an organism inhabits and, subsequently, to use these findings to test a novel hypothesis that fluid environments can impose selective forces acting to constrain asymmetry to maintain or enhance biomechanical function. We examined carapace asymmetry in 114 species (69 aquatic and 45 terrestrial) from the chelonian superfamily Testudinoidea. The results obtained indicate that environment is correlated with the degree of asymmetry, but in different directions for the two clades that comprise the Testudinoidea. Within the Testuguria, aquatic turtles have lower levels of asymmetry than terrestrial turtles, which is consistent with our proposed biomechanical hypothesis. This pattern was not observed within the Emydidae, possibly due to the much shorter time that terrestrial taxa in this clade have existed. Nevertheless, the present study provides the first evidence for a relationship between fluid media and asymmetry in any taxonomic group.
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Papers by Gabriel Rivera