The Death of Bilal al-Sudani and Its Impact on Islamic State Operations

IN LATE JANUARY, the U.S. military conducted an operation in a cave complex located in northern Somalia that resulted in the death of Bilal al-Sudani, a key operative and facilitator for the Islamic State. The raid provides further evidence that Africa has become the “epicenter” for Islamic State activity in particular and for the global Sunni jihadist movement more broadly. Certainly, counterterrorism has been downgraded as a U.S. national security priority. Yet, the use of American military personnel in a risky ground-based operation reflects al-Sudani’s importance as well as the Unite

Reflected Shock Bifurcation in a Square Channel

We examine the bifurcation of a reflected shock in a three-dimensional, square channel through numerical simulations using a distributed memory parallel adaptive mesh refinement, Navier-Stokes solver with multicomponent equation of state and microscopic transport. The three-dimensional, rather than axisymmetric, geometry introduces considerable complexity into the flow structures, particularly in the vicinity of the corners. Spanwise cross-sections show the boundary layer growth is significantly reduced in the corner regions, where the shape of the turbulent jet and recirculation regions are modified. This appears to be consistent with existing experimental studies which report the boundary layer in the corner region is deformed and the propagation velocity is reduced. A pair of triple points and a diagonally-oriented Mach reflection with shear layers directed towards the corner apex are also observed in the spanwise view

Mycobacterium tuberculosis infection as a zoonotic disease: transmission between humans and elephants.

Between 1994 and 1996, three elephants from an exotic animal farm in Illinois died of pulmonary disease due to Mycobacterium tuberculosis. In October 1996, a fourth living elephant was culture-positive for M. tuberculosis. Twenty-two handlers at the farm were screened for tuberculosis (TB); eleven had positive reactions to intradermal injection with purified protein derivative. One had smear-negative, culture-positive active TB. DNA fingerprint comparison by IS6110 and TBN12 typing showed that the isolates from the four elephants and the handler with active TB were the same strain. This investigation indicates transmission of M. tuberculosis between humans and elephants

Selective extinction against redundant species buffers functional diversity

The extinction of species can destabilize ecological processes. A way to assess the ecological consequences of species loss is by examining changes in functional diversity. The preservation of functional diversity depends on the range of ecological roles performed by species, or functional richness, and the number of species per role, or functional redundancy. However, current knowledge is based on short timescales and an understanding of how functional diversity responds to long-term biodiversity dynamics has been limited by the availability of deep-time, trait-based data. Here, we compile an exceptional trait dataset of fossil mollusks from a 23-million-year interval in the Caribbean Sea (34,011 records, 4,422 species) and develop a novel Bayesian model of multi-trait-dependent diversification to reconstruct mollusk (1) diversity dynamics, (2) changes in functional diversity and (3) extinction selectivity over the last 23 million years. Our results identify high diversification between 23 – 5 Ma, leading to increases in both functional richness and redundancy. Conversely, over the last three million years, a period of high extinction rates resulted in the loss of 49% of species but only 3% of functional richness. Extinction rates were significantly higher in small, functionally redundant species suggesting that competition mediated the response of species to environmental change. Taken together, our results identify long-term diversification and selective extinction against redundant species that allowed functional diversity to grow over time, ultimately buffering the ecological functions of biological communities against extinction

A methodology for speeding up loop kernels by exploiting the software information and the memory architecture

It is well-known that today׳s compilers and state of the art libraries have three major drawbacks. First, the compiler sub-problems are optimized separately; this is not efficient because the separate sub-problems optimization gives a different schedule for each sub-problem and these schedules cannot coexist as the refining of one, causes the degradation of another. Second, they take into account only part of the specific algorithm׳s information. Third, they take into account only a few hardware architecture parameters. These approaches cannot give an optimal solution. In this paper, a new methodology/pre-compiler is introduced, which speeds up loop kernels, by overcoming the above problems. This methodology solves four of the major scheduling sub-problems, together as one problem and not separately; these are the sub-problems of finding the schedules with the minimum numbers of (i) L1 data cache accesses, (ii) L2 data cache accesses, (iii) main memory data accesses, (iv) addressing instructions. First, the exploration space (possible solutions) is found according to the algorithm׳s information, e.g. array subscripts. Then, the exploration space is decreased by orders of magnitude, by applying constraint propagation to the software and hardware parameters. We take the C-code and the memory architecture parameters as input and we automatically produce a new faster C-code; this code cannot be obtained by applying the existing compiler transformations to the original code. The proposed methodology has been evaluated for five well-known algorithms in both general and embedded processors; it is compared with gcc and clang compilers and also with iterative compilation

Adhesion of Listeria monocytogenes to materials commonly found in domestic kitchens

The aim of this work was to investigate the adhesion of Listeria monocytogenes ATCC 15313 to glass, granite, marble, polypropylene from a bowl (PPb), polypropylene from a cutting board (PPcb) and stainless steel (SS), which are materials commonly used in kitchens. Marble and granite were chosen because they are applied as kitchen bench covers and pavements in many countries and there are no literature reports on their behaviour in terms of microbial adhesion. The effect of surface hydrophobicity and roughness on the adhesion process was also analysed. The results showed that the highest extent of adhesion of L. monocytogenes occurred to stainless steel, followed by glass and in less extent to the other materials studied. However, it was not possible to establish a correlation between surface hydrophobicity or roughness and the extent of adhesion of L. monocytogenes. The adherence of L. monocytogenes should be dependent on other factors, like the presence of exopolymers and surface charge.Fundação para a Ciência e a Tecnologia (FCT

New mechanism for upset of electronics.

For many decades, engineers and scientists have studied the effects of high power microwaves (HPM) on electronics. These studies usually focus on means of delivering energy to upset electronic equipment and ways to protect equipment from HPM. The motivation for these studies is to develop the knowledge necessary either to cause disruption or to protect electronics from disruption. Since electronic circuits must absorb sufficient energy to fail and the source used to deliver this energy is far away from the electronic circuit, the source must emit a large quantity of energy. In free space, for example, as the distance between the source and the target increases, the source energy must increase by the square of distance. The HPM community has dedicated substantial resources to the development of higher energy sources as a result. Recently, members of the HPM community suggested a new disruption mechanism that could potentially cause system disruptions at much lower energy levels. The new mechanism, based on nonlinear dynamics, requires an expanded theory of circuit operation. This report summarizes an investigation of electronic circuit nonlinear behavior as it applies to inductor-resistor-diode circuits (known as the Linsay circuit) and phased-locked-loops. With the improvement in computing power and the need to model circuit behavior with greater precision, the nonlinear effects of circuit has become very important. In addition, every integrated circuit has as part of its design a protective circuit. These protective circuits use some variation of semiconductor junctions that can interact with parasitic components, present in every real system. Hence, the protective circuit can behave as a Linsay circuit. Although the nonlinear behavior is understandable, it is difficult to model accurately. Many researchers have used classical diode models successfully to show nonlinear effects within predicted regions of operation. However, these models do not accurately predict measured results. This study shows that models based on SPICE, although they exhibit chaotic behavior, do not properly reproduce circuit behavior without modifying diode parameters. This report describes the models and considerations used to model circuit behavior in the nonlinear range of operation. Further, it describes how a modified SPICE diode model improves the simulation results. We also studied the nonlinear behavior of a phased-locked-loop. Phased-locked loops are fundamental building block to many major systems (aileron, seeker heads, etc). We showed that an injected RF signal could drive the phased-locked-loop into chaos. During these chaotic episodes, the frequency of the phased-locked-loop takes excursion outside its normal range of operation. In addition to these excursions, the phased-locked-loop and the system it is controlling requires some time to get back into normal operation. The phased-locked-loop only needs to be upset enough long enough to keep it off balance

Positive and negative affect is related to experiencing chest pain during exercise-induced myocardial ischemia

© 2017 by the American Psychosomatic Society. Objective: Silent myocardial ischemia is thought to be associated with worse cardiovascular outcomes due to a lack of perception of pain cues that initiate treatment seeking. Negative affect (NA) has been associated with increased pain reporting and positive affect (PA) with decreased pain reporting, but these psychological factors have not been examined within the context of myocardial ischemia. This study evaluated the associations between PA, NA, and chest pain reporting in patients with and without ischemia during exercise testing. Methods: A total of 246 patients referred for myocardial perfusion single-photon emission computed tomography exercise stress testing completed the positive and negative affect schedule-expanded version, a measure of PA and NA. Presence of chest pain and myocardial ischemia were evaluated using standardized protocols. Results: Logistic regression analyses revealed that for every 1-point increase in NA, there was a 13% higher chance for ischemic patients (odds ratio [OR] = 1.13; 95 % confidence interval [CI] = 1.02 to 1.26) and an 11% higher chance in nonischemic patients (OR = 1.11; 95% CI = 1.03 to 1.19) to report chest pain. A significant interaction of PA and NA on chest pain reporting (ß = 0.02; 95% CI = 0.002 to 0.031) was also observed; nonischemic patients with high NA and PA reported more chest pain (57%) versus patients with low NA and low PA (13%), with high NA and low PA (17%), and with high PA and low NA (7%). Conclusions: Patients who experience higher NA are more likely to report experiencing chest pain. In patients without ischemia, high NA and PA was also associated with a higher likelihood of reporting chest pain. Results suggest that high levels of PA as well as NA may increase the experience and/or reporting of chest pain

Ringed, Bearded, and Ribbon Seal Vocalizations North of Barrow, Alaska: Seasonal Presence and Relationship with Sea Ice

The acoustic repertoires of ringed, bearded, and ribbon seals are described, along with their seasonal occurrence and relationship to sea ice concentration. Acoustic recordings were made between September and June over three years (2006 – 09) along the continental slope break in the Chukchi Sea, 120 km north-northwest of Barrow, Alaska. Vocalizations of ringed and bearded seals occurred in winter and during periods of 80% – 100% ice cover but were mostly absent during open water periods. The presence of ringed and bearded seal calls throughout winter and spring suggests that some portion of their population is overwintering. Analysis of the repertoire of ringed and bearded seal calls shows seasonal variation. Ringed seal calls are primarily barks in winter and yelps in spring, while bearded seal moans increase during spring. Ribbon seal calls were detected only in the fall of 2008 during the open water period. The repertoire of known ribbon seal vocalizations was expanded to include three additional calls, and two stereotyped call sequences were common. Retrospective analyses of ringed seal recordings from 1982 and ribbon seal recordings from 1967 showed a high degree of stability in call repertoire across large spatial and temporal scales.Le répertoire acoustique des phoques annelés, des phoques barbus et des phoques à bandes sont décrits, de même que leur présence saisonnière et leur rapport avec la concentration de glace de mer. Des enregistrements acoustiques ont été effectués entre septembre et juin sur une période de trois ans (2006 – 2009), le long de la rupture de la pente continentale, dans la mer des Tchouktches, à 120 km au nord-nord-ouest de Barrow, en Alaska. Les vocalisations de phoques annelés et de phoques barbus étaient présentes pendant l’hiver et pendant les périodes où la concentration de glace était de 80 % à 100 %, mais elles se faisaient rares pendant les périodes d’eau libre. La présence des cris de phoques annelés et de phoques barbus tout au long de l’hiver et du printemps suggère qu’une partie de leur population hiverne. L’analyse du répertoire de cris de phoques annelés et de phoques barbus indique une variation saisonnière. L’hiver, le cri du phoque annelé prend principalement la forme d’aboiements, tandis que le printemps, il prend la forme de glapissements. Les gémissements du phoque barbu s’intensifient au printemps. Le cri des phoques à bandes n’a été capté qu’à l’automne 2008, pendant la période des eaux libres. Le répertoire des vocalisations connues du phoque à bandes a été élargi pour inclure trois autres cris, bien que deux séquences de cris stéréotypées étaient courantes. L’analyse rétrospective des enregistrements de cris de phoques annelés de 1982 et de phoques à bandes de 1967 a laissé entrevoir une grande stabilité du point de vue du répertoire des cris, et ce, sur de vastes échelles spatiales et temporelles