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The ongoing development of modern electronic systems leads to smaller, more powerful devices that are expected to operate in complex environments. Due to this, advanced thermal management technologies are required to meet the growing demand, especially in space where two-phase thermal systems are limited by the absence of gravity. Electrohydrodynamic (EHD) and dielectrophoretic (DEP) forces can be used to sustain stable liquid film flow boiling in the absence of gravity, which is otherwise impractical due to the lack of a required buoyancy force to initiate bubble departure. EHD is a phenomenon that is represented by the interaction between electric fields and fluid flow. The DEP force is characterized by its ability to act on liquid/vapor interfaces due to a high gradient of electrical permittivity. This study investigates the heat transfer characteristics of EHD conduction pumping driven liquid film flow boiling coupled with DEP vapor extraction during a microgravity parabolic flight and on the ground. The results of this study show that EHD and DEP raise the critical heat flux, lower heater surface temperature, and successfully sustain boiling in both microgravity and on the ground with low power consumption. Additionally, the heat transfer data captured in terrestrial, microgravity, and 1.8 g conditions compare well, indicating that combining these mechanisms can provide thermal enhancement independent of gravity. This study provides fundamental understanding of electrically driven liquid film flow boiling in the presence of phase change, paving the way toward developing next-generation heat transport devices for space and terrestrial applications.

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The Imaging Spectroscopy Snout (ISS) used at the National Ignition Facility is able to simultaneously collect neutron pinhole images, 1D spatially resolved x-ray spectra, and time resolved x-ray pinhole images. To measure the x-ray spectra, the ISS can be equipped with up to four different transmission crystals, each offering different energy ranges from ∼7.5 to ∼12 keV and different resolutions. Characterizing and calibrating such instruments is of paramount importance in order to extract meaningful results from experiments. More specifically, we characterized different ISS transmission-type alpha-Quartz crystals by measuring their responses as a function of photon energy, from which we inferred the angle-integrated reflectivity for each crystal’s working reflections. These measurements were made at the Lawrence Livermore National Laboratory calibration station dedicated to the characterization of x-ray spectrometers. The sources used covered a wide x-ray range—from a few to 30 keV; the source diameter was ∼0.6 mm. The experimental results are discussed alongside theoretical calculations using the pyTTE model.

Menopause has been linked to changes in memory. Oestrogen-containing hormone therapy is prescribed to treat menopause-related symptoms and can ameliorate memory changes, although the parameters impacting oestrogen-related memory efficacy are unclear. Cognitive experience and practice have been shown to be neuroprotective and to improve learning and memory during ageing, with the type of task playing a role in subsequent cognitive outcomes. Whether task complexity matters, and whether these outcomes interact with menopause and oestrogen status, remains unknown. To investigate this, we used a rat model of surgical menopause to systematically assess whether maze task complexity, as well as order of task presentation, impacts spatial learning and memory during middle age when rats received vehicle, low-17β-oestradiol (E(2)) or high-E(2) treatment. The direction, and even presence, of the effects of prior maze experience differed depending on the E(2) dose. Surgical menopause without E(2) treatment yielded the least benefit, as prior maze experience did not have a substantial effect on subsequent task performance for vehicle treated rats regardless of task demand level during the first exposure to maze experience or final testing. High-dose E(2) yielded a variable benefit, and low-dose E(2) produced the greatest benefit. Specifically, low-dose E(2) broadly enhanced learning and memory in surgically menopausal rats that had prior experience on another task, regardless of the complexity level of this prior experience. These results demonstrate that E(2) dose influences the impact of prior cognitive experience on learning and memory during ageing, and highlights the importance of prior cognitive experience in subsequent learning and memory outcomes.

A comprehensive comparison of the dominant sources of radiation-induced blur for radiographic imaging system performance is made. End-point energies of 6, 10, 15, and 20 MeV bremsstrahlung photon radiation produced at the Los Alamos National Laboratory Microtron facility were used to examine the performance of large-panel cerium-doped lutetium yttrium silicon oxide (LYSO:Ce) scintillators 3, 5 and 10 mm thick. The system resolution was measured and compared between the various end-point energies and scintillator thicknesses. Contrary to expectations, it is found that there was only a minor dependence of system resolution on scintillator thickness or beam end-point energy. This indicates that increased scintillator thickness does not have a dramatic effect on system performance. The data are then compared to Geant4 simulations to assess contributions to the system performance through the examination of modulation transfer functions. It was determined that the low-frequency response of the system is dominated by the radiation-induced signal, while the higher-frequency response of the system is dominated by the optical imaging of the scintillation emission.

Rodent aging research often utilizes spatial mazes, such as the water radial-arm-maze (WRAM), to evaluate cognition. The WRAM can simultaneously measure spatial working and reference memory, wherein these two memory types are often represented as orthogonal. There is evidence, however, that these two memory forms yield interference at a high working memory load. The current study systematically evaluated whether the presence of a reference memory component impacts handling of an increasing working memory load. Young and aged female rats were tested to assess whether aging impacts this relationship. Cholinergic projections from the basal forebrain to the hippocampus and cortex can affect cognitive outcomes, and are negatively impacted by aging. To evaluate whether age-related changes in working and reference memory profiles are associated with cholinergic functioning, we assessed choline acetyltransferase activity in these behaviorally-tested rats. Results showed that young rats outperformed aged rats on a task testing solely working memory. The addition of a reference memory component deteriorated the ability to handle an increasing working memory load, such that young rats performed similar to their aged counterparts. Aged rats also had challenges when reference memory was present, but in a different context. Specifically, aged rats had difficulty remembering which reference memory arms they had entered within a session, compared to young rats. Further, aged rats that excelled in reference memory also excelled in working memory when working memory demand was high, a relationship not seen in young rats. Relationships between cholinergic activity and maze performance differed by age in direction and brain region, reflecting the complex role that the cholinergic system plays in memory and attentional processes across the female lifespan. Overall, the addition of a reference memory requirement detrimentally impacted the ability to handle working memory information across young and aged timepoints, especially when the working memory challenge was high; these age-related deficits manifested differently with the addition of a reference memory component. This interplay between working and reference memory provides insight into the multiple domains necessary to solve complex cognitive tasks, potentially improving the understanding of complexities of age- and disease- related memory failures and optimizing their respective treatments.

The ongoing development of modern electronic systems leads to smaller, more powerful devices that are expected to operate in complex environments. Due to this, advanced thermal management technologies are required to meet the growing demand, especially in space where two-phase thermal systems are limited by the absence of gravity. Electrohydrodynamic (EHD) and dielectrophoretic (DEP) forces can be used to sustain stable liquid film boiling in micro-gravity, which is otherwise impractical due to the lack of a required buoyancy force to initiate bubble departure. EHD and DEP are phenomena that are represented by the interaction between electric fields and fluid flow. The DEP force especially is characterized by the unique ability to act on liquid/vapor interfaces due to a high gradient of electrical permittivity, allowing for two phase operation. This study investigates the effect of EHD conduction pumping coupled with DEP vapor extraction on liquid film flow boiling during a microgravity parabolic flight, and it characterizes the future two-phase microgravity heat transport technology prior to testing on the International Space Station (ISS). The results of this study show that EHD and DEP raise critical heat flux, lower heater surface temperature, and successfully sustain boiling in micro-gravity all at the cost of low power consumption. Additionally, the heat transfer data captured in terrestrial, microgravity, and 1.8 g conditions compare well, indicating that this technology can provide thermal enhancement independent of gravity. This study paves the way for future implementation of EHD-driven two-phase heat transport devices into space and aeronautical electronics applications.

Prototype zoom lenses should be designed with flexibility. One never knows what the future use of a prototype as-build lens will be. In a prior design of a large-image-format zoom lens used for proton radiography, extra back focal distance was constrained in the design to allow for future insertion of extra lenses. These added lenses can change the magnification to a different camera system, having a smaller image size. Three single commercial lens elements were mounted into a commercial variable-length housing barrel that was attached to the back of the zoom lens using a 3Dprinted flange. This new design has been adapted to support neutron radiography; the new configuration collects light from a thick, blue-light-emitting scintillator. After the initial request was made, it took us only three weeks to design, assemble, and conduct imaging tests. The scintillator’s light travels 24 inches before entering into the zoom lens. A large pellicle is inserted into the optical path to keep the zoom lens and camera out of the neutron flux. Because of reduced resolution from the volume scintillator, a five-axis self-leveling alignment laser was sufficient to adjust the tilting of the scintillator, pellicle, zoom lens, and camera. The design process for picking suitable COTS lens elements will be discussed.

Coronavirus disease 2019 (COVID-19) has underscored longstanding societal differences in the drivers of health and demonstrated the value of applying a health equity lens to engage at-risk communities, communicate with them effectively, share data, and partner with them for program implementation, dissemination, and evaluation. Examples of engagement - across diverse communities and with community organizations; tribes; state and local health departments; hospitals; and universities - highlight the opportunity to apply lessons from COVID-19 for sustained changes in how public health and its partners work collectively to prevent disease and promote health, especially with our most vulnerable communities.

As modern-day electronics develop, electronic devices become smaller, more powerful, and are expected to operate in more diverse configurations. However, the thermal control systems that help these devices maintain stable operation must advance as well to meet the demands. One such demand is the advent of flexible electronics for wearable technology, medical applications, and biology-inspired mechanisms. This paper presents the design and performance characteristics of flexible electrohydrodynamic (EHD) pumps, based on EHD conduction pumping technology in macro- and mesoscales. Unlike mechanical pumps, EHD conduction pumps have no moving parts, can be easily adjusted to the microscale, and have been shown to generate and control the flow of refrigerants for electronics cooling applications. However, these pumping devices have only been previously tested in rigid configurations unsuitable for use with flexible electronics. In this work, for the first time, the net flow generated by flexible EHD conduction pumps is measured on a flat plane in various configurations. In this study, the results show that the flexible EHD conduction pumps are capable of generating significant flow velocities in all size scales considered in this study, with and without bending. This study also proves the viability of screen printing as a manufacturing method for these pumps. The selection of working fluid for EHD conduction pumping is also a topic of discussion. Novec Engineered Fluids have been a popular choice for EHD pumping; however, long-term testing has shown that some Novec fluids degrade over time.

After the Spanish-American War (1898), many anarchists began to focus their attention on the rising discontent among Mexico’s landless working class. The Flores Magón brothers sought to galvanize support for revolutionary change in Mexico, and they received welcome support from Spanish anarchists, including Jaime Vidal and Pedro Esteve. In particular, Jaime Vidal, who had also helped to organize Spanish firemen on the East Coast sought to promote and assist Magónismo. Through his essays, his several anarchist periodicals, and fund-raising activities in both New York and California, Jaime Vidal helped to incorporate and promote the Magón’s efforts in the transnational anarchist print network.

Hispanic intervention in the colonial history of the Americas is well-known.1 Much less understood is the modern Hispanic migration to, and struggle for freedom in, the United States. To better understand the complexities of this intersectional migration, we focus on the lives of Hispanic anarchists, libertarians, and free thinkers who rejected the hallmarks of traditional society—church, state, and capitalism—because they deemed those institutions to be oppressive and tyrannical. In their endeavor to create a truly equitable society built upon the ideals of liberty and justice for all, these anarchists developed a vibrant network of transnational periodicals from the late 19th through 20th centuries....

High-energy X-ray radiographic image restoration is performed using a simulated radiation point spread function and an experimentally derived optical point spread function. It is shown that a robust method for removal of thick monolithic scintillator blur can be determined through independent examination of the blur components. We show that the scintillator blur for a 20 MeV end-point X-ray beam and 20 mm thick LYSO scintillator contributes significantly to the system blur. It is also shown that the optical scatter in the monolithic crystal degrades the low-frequency response of the system. The use of a simulated point spread function for image restoration using deconvolution provides a simple method for image restoration, thereby enhancing feature identification and areal density reconstruction.

This Technical Memorandum (TM) summarizes the Fermilab Test Beam Faciltiy (FTBF) operations for FY2019. It is one of a series of annual publications intended to gather information in one place. This TM discusses the experiments performed at the Test Beam from November 2018 to July 2019. The experiments are listed in Table 1. Each experiment wrote a summary that was edited for clarity and is included in this report.

Summary Neither the limits of elements and processes of the petroleum systems of Colombian sedimentary basins are known nor interpreted without ambiguities undermining the reservoir complexities and hampering the data integration in the upstream business. Partly it is due to poor understanding of the datasets and poorly articulated data modelling, visualization and interpretation artefacts in complex geological regimes. We propose an ontology based multidimensional warehouse repository approach with ontology constructs and models for various data sources, acquired from multiple domains of upstream business. We choose several data volumes, variety of multidimensional data attributes and their fact instances for interpreting seismically integrated geological horizons. Structure and fracture attribute map views are computed to ascertain the density of fractures and their orientations, calibrating the fracture signatures with production data existing within the interpreted faulted compartments. Field development plans are assessed based on new knowledge, obtained from domain ontology descriptions, exploring connections among multi-stacked fractured reservoirs. Though we find no structural bearing on the accumulations of oil and gas in the study area, the fracture density and orientation appear to have definite bearing on production. Integrated framework minimizes the ambiguity involved in the interpretation of fractures, their density and orientations in the study area.

Gait Analysis involves analyzing human walking, particularly its temporal parameters. Gait parameters (cadence, step length, trajectory of center of mass, etc) require measurements oflower-limb joint angles. The most commonly used techniques for gait analysis are optical systems. However, these systems have several drawbacks which include: markers need to be attached to the human body; it is required a considerable amount of time for setting up the experimental session; High cost; Bulk and space requirements; finally, they are restricted to a limited place or laboratory. Inertial measurement units (IMU) can be used in body-worn biomechanical monitoring devices for movement data collection in daily life.This paper presents a system based on 2 IMUs for knee joint angle monitoring to be used for long-time periods in out-of-lab daily life. For validation, the system was compared to a vision-based motion capture system, in a set of experiments involving walking on a treadmill under three different velocities (slow-speed, normal-speed, high-speed). Obtained results showed high correlation (>0.94) between measurements from the developed device and the vision-based motion capture system, according to the obtained concordance correlation coefficients.

To date, therapies to prevent or treat Alzheimer’s disease (AD) have largely focused on removing excess aggregation-prone amyloid peptide Aβ from the brain, an approach that has produced disappointing clinical outcomes. An alternative hypothesis proposes that Aβ production and aggregation is a symptom of a larger, systemic disease affecting the regulation of lipids, including cholesterol. In this scenario, lipid dysregulation would likely occur early in the disease process, making it an ideal target for predicting risk of mild cognitive impairment (MCI) to AD conversion. Here, we report that levels of filipin, a fluorescent polyene macrolide widely used as a diagnostic tool for diseases of lipid dysregulation, correlate with cellular damage caused by 27-hydroxycholesterol and with dementia status in human peripheral blood cells. These results provide strong preliminary data suggesting that filipin could be of use in the development of a quick and inexpensive method to measure the risk of AD conversion in patients with MCI, supplementing existing testing strategies that focus on the consequences of Aβ accumulation.

There is growing interest in using low-energy flash x-ray sources in radiographic applications to provide high-contrast images of low-density objects. Due to the low-energy nature of the detected photons, thin bright scintillators are desired. In order to pursue an optimum radiographic system, experimental studies have been performed of the static imaging properties of thin microcolumnar CsI using a Platts x-ray source. The Platts source is a nominally 300 keV endpoint rod pinch diode x-ray source with a ~35 ns pulse time. The source was used to measure the imaging properties of microcolumnar CsI with various thicknesses and backings. The experimental setup was modeled in GEANT4, and the images were simulated to estimate system performance. Taking into account the source photon production, radiation transport, and system optical performance, an accurate assessment of the detection system can be deduced.

Robotics courses play a central role in the electronic engineering curriculum. Those courses provide students with knowledge and skill in multiple aspects of the design, simulation, implementation and operation of systems using robotics technologies for applications in areas such as the industrial, medical, services, among others. This work describes the implementation and application of a Matlab-based platform using low-cost technologies as an educational tool to be included in robotics courses. The platform comprises an Arduino as a target for hardware in the loop (HIL) simulation using Matlab and a 6 Degree of Freedom (DoF) articulated robotic arm. The HIL simulation system differs from computer simulation in such a way that it involves actual hardware and permits controlling the real world actuators and sensors. It was carried out set of experiments aimed to evaluate the platform in the field of human-robot interaction; specifically, through an application to control the robotic arm to follow movements of a human upper limb. Root Mean Square Error (RMSE) was used to correlate movement provided by user and the actual movement executed by the robotic arm. Obtained mean measurement errors were RMSE of 4.7 ° for static validation and 5.3 ° for dynamic tests.

MicroRNAs (miRNAs) are small non-coding RNAs of ~22 nucleotides that function as negative regulators of gene expression by either inhibiting translation or inducing deadenylation-dependent degradation of target transcripts. Notably, deregulation of miRNAs expression is associated with the initiation and progression of human cancers where they act as oncogenes or tumor suppressors contributing to tumorigenesis. Abnormal miRNA expression may provide potential diagnostic and prognostic tumor biomarkers and new therapeutic targets in cancer. Recently, several miRNAs have been shown to initiate invasion and metastasis by targeting multiple proteins that are major players in these cellular events, thus they have been denominated as metastamiRs. Here, we present a review of the current knowledge of miRNAs in cancer with a special focus on metastamiRs. In addition we discuss their potential use as novel specific markers for cancer progression.

The single tyrosyl-tRNA synthetase (TyrRS) gene in trypanosomatid genomes codes for a protein that is twice the length of TyrRS from virtually all other organisms. Each half of the double-length TyrRS contains a catalytic domain and an anticodon-binding domain; however, the two halves retain only 17% sequence identity to each other. The structural and functional consequences of this duplication and divergence are unclear. TyrRS normally forms a homodimer in which the active site of one monomer pairs with the anticodon-binding domain from the other. However, crystal structures of Leishmania major TyrRS show that, instead, the two halves of a single molecule form a pseudo-dimer resembling the canonical TyrRS dimer. Curiously, the C-terminal copy of the catalytic domain has lost the catalytically important HIGH and KMSKS motifs characteristic of class I aminoacyl-tRNA synthetases. Thus, the pseudo-dimer contains only one functional active site (contributed by the N-terminal half) and only one functional anticodon recognition site (contributed by the C-terminal half). Despite biochemical evidence for negative cooperativity between the two active sites of the usual TyrRS homodimer, previous structures have captured a crystallographically-imposed symmetric state. As the L. major TyrRS pseudo-dimer is inherently asymmetric, conformational variations observed near the active site may be relevant to understanding how the state of a single active site is communicated across the dimer interface. Furthermore, substantial differences between trypanosomal TyrRS and human homologs are promising for the design of inhibitors that selectively target the parasite enzyme.

The great power of protein crystallography to reveal biological structure is often limited by the tremen26 dous effort required to produce suitable crystals. A hybrid crystal growth predictive model is presented 27 that combines both experimental and sequence-derived data from target proteins, including novel vari28 ables derived from physico-chemical characterization such as R30, the ratio between a protein’s DSF 29 intensity at 30 C and at Tm. This hybrid model is shown to be more powerful than sequence-based pre30 diction alone – and more likely to be useful for prioritizing and directing the efforts of structural genom31 ics and individual structural biology laboratories. 32

New drugs are needed to treat toxoplasmosis. Toxoplasma gondii calcium-dependent protein kinases (TgCDPKs) are attractive targets because they are absent in mammals. We show that TgCDPK1 is inhibited by low nanomolar levels of bumped kinase inhibitors (BKIs), compounds designed to be inactive against mammalian kinases. Cocrystal structures of TgCDPK1 with BKIs confirm that the structural basis for selectivity is due to the unique glycine gatekeeper residue in the ATP-binding site at residue 128. We show that BKIs interfere with an early step in T. gondii infection of human cells in culture. Furthermore, we show that TgCDPK1 is the in vivo target of BKIs because T. gondii cells expressing a glycine to methionine gatekeeper mutant enzyme show significantly decreased sensitivity to this class of selective kinase inhibitors. Thus, design of selective TgCDPK1 inhibitors with low host toxicity may be achievable.

This study sought to determine whether the quality of enzyme preparations can be determined from their melting curves, which may easily be obtained using a fluorescent probe and a standard reverse transcription-polymerase chain reaction (RT-PCR) machine. Thermal melt data on 31 recombinant enzymes from Plasmodium parasites were acquired by incrementally heating them to 90 degrees C and measuring unfolding with a fluorescent dye. Activity assays specific to each enzyme were also performed. Four of the enzymes were denatured to varying degrees with heat and sodium dodecyl sulfate (SDS) prior to the thermal melt and activity assays. In general, melting curve quality was correlated with enzyme activity; enzymes with high-quality curves were found almost uniformly to be active, whereas those with lower quality curves were more varied in their catalytic performance. Inspection of melting curves of bovine xanthine oxidase and Entamoeba histolytica cysteine protease 1 allowed active stocks to be distinguished from inactive stocks, implying that a relationship between melting curve quality and activity persists over a wide range of experimental conditions and species. Our data suggest that melting curves can help to distinguish properly folded proteins from denatured ones and, therefore, may be useful in selecting stocks for further study and in optimizing purification procedures for specific proteins.

The medial prefrontal cortex (mPFC) and nucleus accumbens (NAc) are 2 structures within a larger corticolimbic network mediating goal-directed actions, especially when the procurement of different goals is sensitive to impulsive tendencies. The present study investigated the role of these structures in goal-directed action for differential reward by training rats to respond for sucrose reward at a nosepoke operandum such that longer duration nosepokes (up to 2 s) resulted in correspondingly larger volumes of reward. After 16 weeks of training, neurotoxic lesions of either the mPFC or the NAc-core were performed, followed by reassessment of sustained response behavior. Lesions of mPFC increased choice impulsivity by shifting responding away from large rewards toward rewards of smaller sizes. The total volume of reward earned remained unchanged, thereby dissociating the lesion effects on response parameters from overall motivation for reward. In contrast, NAc-core lesions decreased the total amount of responding and total volume of reward earned without altering choice impulsivity across differing nosepoke durations and reward sizes. These results suggest that the mPFC mediates the ability to maintain behavioral responding over longer durations for larger magnitude rewards, while the NAc-core mediates the initiation of responding, perhaps by affecting motivational drive, independent of reward magnitude.

Inspired by our experience addressing the legacy of eugenics at California State University, Sacramento, this special issue presents an array of articles representative of diverse approaches to the historical investigation of eugenics. This article provides an introduction to the history of eugenics and explores the ways in which public history is particularly well suited to shape the historical memory of eugenics and encourage dialogue about contemporary biotechnologies.

This article is a case study of how natural gas pipelines have been treated under the National Historic Preservation Act (NHPA). It examines three recent pipeline projects that involved determinations of eligibility for the National Register of Historic Places. In one case, a pipeline firm sought an exemption from Section 106 review, and this led to a proposed congressional amendment to the NHPA. In order to forestall a legislative amendment, the Advisory Council on Historic Preservation issued an administrative exemption from Section 106 review for natural gas pipelines. This essay traces the process and events that led to this exemption.

In this paper, the effect of antenna sectorization in the reverse link erlang capacity of a multiclass code-division multiple-access (CDMA) cellular system is studied. Traditionally, it has been considered that the capacity is multiplied by a factor equal to the number of sectors introduced. This is true only in the ideal antenna sectored system. However, due to the nonideal antenna radiation pattern, the sectorization gain is smaller than the number of sectors. Our contribution is the analytical study of the effect of nonideal antenna patterns on the capacity of a multiclass CDMA system. We also present an approximated analysis of the erlang capacity, considering that blocking in CDMA occurs when the interference reaches a predetermined level above the background noise level of mainly thermal origin. The analysis also includes the effects of imperfect power control and service activity detection. We found that the capacity losses due to the consideration of antenna sectorization are about 20.20% for the nonideal antenna radiation pattern and 30.32% for the evaluated commercial radiation pattern. This percentage loss implies that the sectorization gain is approximately 2.39 for a nonideal antenna pattern and 2.09 for a commercial antenna pattern in typical conditions, /spl mu/=4 and /spl alpha/=8 dB.

Oral therapy has become first line treatment for patients with mild to moderate erectile dysfunction (ED). Studies have shown that sildenafil may not be effective in all patients, and has been associated with a variety of adverse effects and an adverse interaction with nitrates and inhibitors of cytochrome P450 enzymes. The objective was to compare the efficacy and safety of three different oral combinations with the highest dose of sildenafil in men with moderate to severe ED. Randomized, double blind, unblinded active-controlled, Phase II study was carried out at three sites in Mexico. After a 4-week placebo run-in period, patients received all four of the following treatments using a 4-way cross-over design: 40 mg phentolamine (PM) +6 mg apomorphine (Apo); 40 mg PM +150 mg papaverine (Pap); 40 mg PM +6 mg Apo +150 mg Pap (Tricombo); 100 mg sildenafil (SC). With the exception of sildenafil tablets, all study medication was blinded. Moderate to severe ED was defined as a less than 50% vaginal penetration success rate during the placebo run-in period. A total of 44 patients were enrolled, of whom 36 completed all four treatment periods. All treatments produced a significant effect in primary efficacy variable (Sexual Encounter Profile) compared to baseline, however, no statistically significant differences were found between treatments. A significant period effect was observed. Also, the four treatments were found not to differ significantly in five out of six secondary efficacy variables. The lowest incidence of treatment-related adverse events (AE) occurred in the 40 mg PM +6 mg Apo group (9.8%), followed by 100 mg SC (15%), and the other two combinations (16.7 and 17.5%, respectively). Nasocongestion and headache were the most frequently reported AE. An oral combination of vasoactive agents may provide an alternative approach to sildenafil. Based on these results a combination of phentolamine and apomorphine warrants further clinical investigation.

Natural gas is experiencing a period of strong growth. Increased resource estimates, and improvements in production and transport technologies are allowing it to fill an expanding role in energy supply, and in important demand sectors such as electricity generation. In the USA, a rapid increase in production from ‘unconventional’ sources (e.g. shale) has resulted in an abundance of low-priced natural gas, encouraging a shift from coal to gas in power generation. Since natural gas is a fuel with inherently lower carbon content than coal, that shift has contributed to a significant decline in USA greenhouse gas emissions. Life-cycle greenhouse gas emissions from natural gas systems is one of the many, real and perceived, factors concerning natural gas development and the industry's social licence to operate. A wealth of recent data on GHG emissions from contemporary natural gas systems is now emerging. This information will facilitate both the accurate comparison of alternative technologies and the management of emissions so that gas resources can be developed prudently, to displace other, more carbon emission-intensive options and contribute to economic growth. This paper draws on material from an IPIECA workshop in 2012, and focuses on the expanding role of natural gas, the new resource base estimates, its GHG footprint compared to other energy sources, and projected demands from different sectors.

Fundamento El perfil farmacologico del propofol ha facilitado su uso en la sedacion prolongada de pacientes con enfermedad pulmonar en cuidados intensivos. Los efectos del propofol sobre el corazon y la circulacion sistemica han sido estudiados con detalle. Sin embargo, sus efectos sobre la circulacion pulmonar son menos conocidos. En este estudio analizamos los efectos del propofol sobre la vasoconstriccion pulmonar hipoxica (VPH). Metodos Se midieron los cambios de la vasoconstriccion pulmonar por hipoxia y angiotensina II antes y tras administrar propofol e intralipid en 42 preparaciones de pulmones aislados de ratas. Propofol e intralipid se aportaron entre dos pares de respuestas a hipoxia (grupos B, C, D y E) y angiotensina (F). Resultados El grupo A fue el control. El grupo B fue tratado con 2 μg/ml de propofol; las respuestas a la hipoxia fueron de 10,41 (5,70) mmHg antes de propofol y 11,17 (5,17) mmHg tras propofol (p = 0,096). En el grupo C la concentracion de propofol fue de 8 μg/ml y las respuestas fueron de 7,39 (2,37) y 8,75 (2,60) (p = 0,063). En el grupo D, la preparacion fue pretratada con azul de metileno (140 μμol/l) y propofol 8 μg/ml, siendo las respuestas de 15,20 (2,28) y 15,60 (3,50) (p = 0,739). En el grupo E, se aportaron 20 μl de intralipid al 20% entre la segunda y tercera respuestas a la hipoxia. La respuesta previa a intralipid fue de 9,82 (3,96) mmHg y de 10,84 (3,68) mmHg las posteriores (p = 0,163). En el grupo F, se estudiaron 2 respuestas a angiotensina II antes y tras propofol 8 μg/ml. Las respuestas fueron de 7,55 (1,87) y 7,94 (2,40) mmHg (p = 0,41), respectivamente. Conclusiones El propofol a las concentraciones estudiadas no modifica la VPH en el pulmon aislado de rata.

BUSINESS HISTORY is both an area of specialization in academic history and a form of public history. Sitting at the intersection of these two disciplines, the practice of business history embodies many of the tensions that exist between traditional academic history and public history. Academic business historians, particularly those who engage in contract or sponsored history, utilize the public historian's principles and techniques while conducting research and writing projects often designed for the academy.' This essay will the examine the public historical aspect of business history, first by discussing major issues in contract business history and then by probing three contract projects focused on twentieth-century firms. The public history character of business history is defined in large part by the business historian's need for access to privately owned records. Although useful sources of business information became public beginning in