bluuebunny/crossref_metadata_2025 huggingface dataset:
Categories of Life: The Status of the Camp in Derrida and Agamben
Authors: Cisney Vernon
Published: March 2010

This essay is an exploration of the relationship between Agamben's 1995 text, Homo Sacer, and Derrida's 1992 “Force of Law” essay. Agamben attempts to show that the camp, as the topological space of the state of exception, has become the biopolitical paradigm for modernity. He draws this conclusion on the basis of a distinction, which he finds in an essay by Walter Benjamin, between categories of life, with the “pro‐tagonist” of the work being what he calls homo sacer, or bare life—life that is stripped of its humanity and value. Five years earlier, in 1990, Derrida had given a lecture at UCLA (later published in its entirety as “The Force of Law”) in which he had analyzed the very same essay by Benjamin and had highlighted the distinction between “base life” and “just life.” The implications of his analysis show a discomforting prox‐imity between Benjaminian messianism and the Nazi “final solution,” a conclusion that Agamben dismisses entirely. In this paper, however, I demonstrate that the structures of the two works are quite similar in many important ways. I argue that, though the broad scope of Agamben's work is original in many respects, and I would not wish to reduce Agamben's work to Derridean repetitions, he nevertheless utilizes much more of Derrida's analysis, specifically with respect to the categori‐zation of life, than he would like the reader to believe.
Moral Status As a Matter of Degree?
Authors: DeGrazia David
Published: March 2010

Some people contend that fetuses have moral status but less than that of paradigm persons. Many people hold views implying that sentient animals have moral status but less than that of persons. These positions suggest that moral status admits of degrees. Does it? To address this question, we must first clarify what it means to speak of degrees of moral status. The paper begins by clarifying the more basic concept of moral status and presenting two models of degrees of moral status. It then sketches several significant considerations in favor of, and several against, the assertion of degrees of moral status. The paper concludes by drawing lessons from the discussion.
Four Varieties of Character‐Based Virtue Epistemology
Authors: Baehr Jason
Published: March 2010

The terrain of character‐based or “responsibilist” virtue epistemology has evolved dramatically over the last decade — so much so that it is far from clear what, if anything, unifies the various views put forth in this area. In an attempt to bring some clarity to the overall thrust and structure of this movement, I develop a fourfold classification of character‐based virtue epistemologies. I also offer a qualified assessment of each approach, defending a certain account of the probable future of this burgeoning subfield.
Putting the Burden of Proof in Its Place: When Are Differential Allocations Legitimate?
Authors: Dare Tim , Kingsbury Justine
Published: March 2010

It is widely assumed that legitimate differential allocations of the burden of proof are ubiquitous: that in all cases in which opposing views are being debated, one side has the responsibility of proving their claim and if they fail, the opposing view wins by default. We argue that the cases in which one party has the burden of proof are exceptions. In general, participants in reasoned discourse are all required to provide reasons for the claims they make. We distinguish between truth‐directed and non‐truth‐directed discourse, argue that the paradigm contexts in which there are legitimate differential allocations of the burden of proof (law and formal debate) are non‐truth‐directed, and suggest that in truth‐directed contexts, except in certain special cases, differential allocation of the burden of proof is not warranted.
A Phenomenology for Homi Bhabha's Postcolonial Metropolitan Subject
Authors: Lee Emily S.
Published: March 2010

Homi Bhabha attends to the figure of the postcolonial metropolitan subject — a racialized subject who is not representative of the first world, yet a symbol of the metropolitan sphere. Bhabha describes their daily lives as inextricably split or doubled. His analysis cannot account for the agonistic moments when one is caught in not knowing, in focusing attention, and in developing understanding. Maurice Merleau‐Ponty's phenomenology with the openness in the horizon of the gestaltian framework better accounts for such splits as moments on the horizon for becoming and grasping something new.
Malebranche and Descartes on Method: Psychologism, Free Will, and Doubt
Authors: Scott David
Published: March 2010

The subject of this paper is Malebranche's relation to Descartes on the question of method. Using recent commentary as a springboard, it examines whether Malebranche advances a nonpsychologistic account of method, in contrast to the psychologism typically thought to characterize the Cartesian view. I explore this question with respect to two issues of central importance to method generally: doubt and free will. My argument is that, despite superficial differences of emphasis, Descartes and Malebranche adopt positions on doubt and free will that effectively ensure that their respective accounts of method are substantially the same.
Leibniz on Concurrence and Efficient Causation
Authors: Bobro Marc E.
Published: March 2010

Leibniz defends concurrentism, the view that both God and created substances are causally responsible for changes in the states of created substances. Interpretive problems, however, arise in determining just what causal role each plays. Some recent work has been revisionist, greatly downplaying the causal role played by created substances—arguing instead that according to Leibniz only God has productive causal power. Though bearing some causal responsibility for changes in their perceptual states, created substances are not efficient causes of such changes. This paper argues against such revisionism; not only was Leibniz a consistent advocate of concurrentism (at least in his “mature” years), but also his account of concurrentism involves both God and created substances as efficient causes of the changes in the states of created substances.
Biological Species Are Natural Kinds
Authors: Elder Crawford L.
Published: March 2010

This paper argues that typical biological species are natural kinds, on a familiar realist understanding of natural kinds—classes of individuals across which certain properties cluster together, in virtue of the causal workings of the world. But the clustering is far from exceptionless. Virtually no properties, or property‐combinations, characterize every last member of a typical species—unless they can also appear outside the species. This motivates some to hold that what ties together the members of a species is the ability to interbreed, others that it is common descent. Yet others hold that species are scattered individuals, of which organisms are parts rather than members. But not one of these views absolves us of the need to posit a typical phenotypic profile. Vagueness is here to stay. Some seek to explain the vagueness by saying species are united by “homeostatic property clusters”; but this view collapses into the more familiar realist picture.
Tension within Triangulation
Authors: Goldberg Nathaniel
Published: March 2010

Philosophers disagree about how meaning connects with history. Donald Davidson, who helped deepen our understanding of meaning, even disagreed with himself. As Ernest Lepore and Kirk Ludwig note, Davidson's account of radical interpretation treats meaning as ahistorical; his Swampman thought experiment treats it as historical. Here I show that while Lepore and Ludwig are right that Davidson's views are in tension, they are wrong about its extent. Unbeknownst to them, Davidson's account of radical interpretation and Swampman thought experiment both rely—in different ways—on the same model of triangulation. I revise one of those ways to resolve the tension within Davidson's views. I close by detailing what role history should play in Davidson's views overall.
Open your eyes and look harder! (An investigation into the idea of a responsible visual search)
Authors: Schroer Robert
Published: March 2010

In this paper, I explore and defend the idea that we have epistemic responsibilities with respect to our visual searches, responsibilities that are far more fine‐grained and interesting than the trivial responsibilities to keep our eyes open and “look hard.” In order to have such responsibilities, we must be able to exert fine‐grained and interesting forms of control over our visual searches. I present both an intuitive case and an empirical case for thinking that we do, in fact, have such forms of control over our visual searches. I then show how these forms of control can be used to aim the visual beliefs that result from our searches toward various epistemic goals.
Reasons, Motivations, and Obligations
Authors: Wyckoff Jason
Published: March 2010

I argue against Reasons Internalism, the view that possession of a normative reason for the performance of an action entails that one can be motivated to perform that action, and Motivational Existence Internalism, the view that if one is obligated to perform an action, then one can be motivated to perform that action. My thesis is that these positions cannot accommodate the fact that reasonable moral agents are frequently motivated to act only because they believe their contemplated actions to be morally obligatory. The failure to accommodate this fact is reason to reject these two types of internalism about reasons.
The Solution to the Surprise Exam Paradox
Authors: Levy Ken
Published: March 2010

The Surprise Exam Paradox continues to perplex and torment despite the many solutions that have been offered. This paper proposes to end the intrigue once and for all by refuting one of the central pillars of the Surprise Exam Paradox, the “No Friday Argument,” which concludes that an exam given on the last day of the testing period cannot be a surprise. This refutation consists of three arguments, all of which are borrowed from the literature: the “Unprojectible Announcement Argument,” the “Wright & Sudbury Argument,” and the “Epistemic Blindspot Argument.” The reason that the Surprise Exam Paradox has persisted this long is not because any of these arguments is problematic. On the contrary, each of them is correct. The reason that it has persisted so long is because each argument is onlypartof the solution. The correct solution requires all three of them to be combined together. Once they are, we may seeexactlywhy the No Friday Argument fails and therefore why we have a solution to the Surprise Exam Paradox that should stick.
A Defense of Descriptive Moral Content
Authors: Wisdom Jeff
Published: March 2010

Terry Horgan and Mark Timmons have recently provided an updated presentation and defense of a metaethical view that they call cognitivist expressivism. Expressivists claim that moral judgments express propositional attitudes that do not represent or describe the external world. Horgan and Timmons agree with this claim, but they also deny the traditional expressivist claim that moral judgments do not express beliefs. On their view, moral judgments are genuine, truth‐apt beliefs, thus making their form of expressivism a cognitivist one. In this essay, I argue that Horgan and Timmons have failed to demonstrate that moral judgments express sui generis, nondescriptive content by showing that at least some moral content is descriptive. In addition, I show how the descriptivist can account for those properties that Horgan and Timmons consider distinctive of moral belief. In doing so, I remove one of the expressivist's most important lines of motivation for positing nondescriptive moral content in the first place. At the end of the essay, I briefly sketch a view that I call partial or modest moral realism.
Free Love: A Hegelian Defense of Same‐Sex Marriage Rights
Authors: Vernon Jim
Published: March 2010

By revisiting Hegel's Philosophy of Right, I mount a Hegelian defense of same‐sex marriage rights. I first argue that Hegel's account of the Idea of freedom articulates both the necessity of popular shifts in the determinations of the institutions of right, as well as the duty to struggle to progressively actualize freedom through them. I then contend that Hegel, by grounding marriage in free consent, clears the path for expanding this ethical institution to include all monogamous couples. Lastly, I close by sketching the specifically Hegelian reasons we ought to actively struggle to expand the institution of marriage.
Illusory movements of a phantom hand grade with the duration and magnitude of motor commands
Authors: Walsh Lee D. , Gandevia Simon C. , Taylor Janet L.
Published: March 2010

The senses of limb movement and position are critical for accurate control of movement. Recent studies show that central signals of motor command contribute to the sense of limb position but it is not clear whether such signals influence the distinctly different sense of limb movement. Nine subjects participated in two experiments in which we inflated a cuff around their upper arm to produce an ischaemic block, paralysing and anaesthetising the forearm, wrist and hand. This produces an experimental phantom wrist and hand. With their arm hidden from view subjects were asked to make voluntary efforts with their blocked wrist. In the first experiment, efforts were 20 and 40% of maximum and were 2 and 4 s in duration. The second experiment used 1 and 5 s efforts of 5 and 50% of maximum. Subjects signalled perceived movements of their phantom wrist using a pointer. All subjects reported clear perceptions of movement of their phantom hand for all levels and durations of effort. On average, subjects perceived their phantom wrist to move between 16.4 ± 3.3 deg (mean ± 95% confidence interval (CI)) and 30.2 ± 5.4 deg in the first experiment and between 10.3 ± 3.5 and 38.6 ± 6.7 deg in the second. The velocity of the movements and total displacement of the phantom graded with the level of effort, and the total displacement also graded with duration. Hence, we have shown that motor command signals have a novel proprioceptive role in the perception of movement of human joints.
The calcium‐permeable non‐selective cation channel TRPM2 is modulated by cellular acidification
Authors: Starkus John G. , Fleig Andrea , Penner Reinhold
Published: March 2010

TRPM2 is a calcium‐permeable non‐selective cation channel expressed in the plasma membrane and in lysosomes that is critically involved in aggravating reactive oxygen species (ROS)‐induced inflammatory processes and has been implicated in cell death. TRPM2 is gated by ADP‐ribose (ADPR) and modulated by physiological processes that produce peroxide, cyclic ADP‐ribose (cADPR), nicotinamide adenine dinucleotide phosphate (NAADP) and Ca2+. We investigated the role of extra‐ and intracellular acidification on heterologously expressed TRPM2 in HEK293 cells. Our results show that TRPM2 is inhibited by external acidification with an IC50 of pH 6.5 and is completely suppressed by internal pH of 6. Current inhibition requires channel opening and is strongly voltage dependent, being most effective at negative potentials. In addition, increased cytosolic pH buffering capacity or elevated [Ca2+]i reduces the rate of current inactivation elicited by extracellular acidification, and Na+ and Ca2+ influence the efficacy of proton‐induced inactivation. Together, these results suggest that external protons permeate TRPM2 channels to gain access to an intracellular site that regulates channel activity. Consistent with this notion, single‐channel measurements in HEK293 cells reveal that internal protons induce channel closure without affecting single‐channel conductance, whereas external protons affect channel open probability as well as single‐channel conductance of native TRPM2 in neutrophils. We conclude that protons compete with Na+ and Ca2+ for channel permeation and channel closure results from a competitive antagonism of protons at an intracellular Ca2+ binding site.
Decreased
In Vitro
Susceptibility of
Plasmodium falciparum
Isolates to Artesunate, Mefloquine, Chloroquine, and Quinine in Cambodia from 2001 to 2007
Authors: Lim Pharath , Wongsrichanalai Chansuda , Chim Pheaktra , Khim Nimol , Kim Saorin , Chy Sophy , Sem Rithy , Nhem Sina , Yi Poravuth , Duong Socheat , Bouth Denis Mey , Genton Blaise , Beck Hans-Peter , Gobert Jean Gerard , Rogers William O. , Coppee Jean-Yves , Fandeur Thierry , Mercereau-Puijalon Odile , Ringwald Pascal , Le Bras Jacques , Ariey Frederic
Published: March 2010

This study describes the results of
in vitro
antimalarial susceptibility assays and molecular polymorphisms of
Plasmodium falciparum
isolates from Cambodia. The samples were collected from patients enrolled in therapeutic efficacy studies (TES) conducted by the Cambodian National Malaria Control Program for the routine efficacy monitoring of artemisinin-based combination therapy (ACT) (artesunate-mefloquine and artemether-lumefantrine combinations). The isolates (
n
= 2,041) were obtained from nine sentinel sites during the years 2001 to 2007. Among these, 1,588 were examined for their
in vitro
susceptibilities to four antimalarials (artesunate, mefloquine, chloroquine, and quinine), and 851 isolates were genotyped for single nucleotide polymorphisms (SNPs). The geometric means of the 50% inhibitory concentrations (GMIC
50
s) of the four drugs tested were significantly higher for isolates from western Cambodia than for those from eastern Cambodia. GMIC
50
s for isolates from participants who failed artesunate-mefloquine therapy were significantly higher than those for patients who were cured (
P
, <0.001).
In vitro
correlation of artesunate with the other drugs was observed. The distributions of the SNPs differed between eastern and western Cambodia, suggesting different genetic backgrounds of the parasite populations in these two parts of the country. The GMIC
50
s of the four drugs tested increased significantly in eastern Cambodia during 2006 to 2007. These results are worrisome, because they may signal deterioration of the efficacy of artesunate-mefloquine beyond the Cambodian-Thai border.
Synergistic Activities of Three Triazoles with Caspofungin against
Candida glabrata
Isolates Determined by Time-Kill, Etest, and Disk Diffusion Methods
Authors: Kiraz Nuri , Dag Ilknur , Yamac Mustafa , Kiremitci Abdurrahman , Kasifoglu Nilgun , Oz Yasemin
Published: March 2010

Combinations of voriconazole, fluconazole, and itraconazole with caspofungin were evaluated against 50
Candida glabrata
isolates by the time-kill, disk diffusion, and Etest methods. The majority of antifungal combinations were indifferent. By the time-kill method, synergistic activity was detected with eight (16%) of the caspofungin-voriconazole and seven (14%) of the caspofungin-fluconazole combinations, but synergy was not seen with the caspofungin-itraconazole combination. Further comparisons of the Etest and disk diffusion synergy techniques with the time-kill method are warranted.
Detection of E119V and E119I Mutations in Influenza A (H3N2) Viruses Isolated from an Immunocompromised Patient: Challenges in Diagnosis of Oseltamivir Resistance
Authors: Okomo-Adhiambo Margaret , Demmler-Harrison Gail J. , Deyde Varough M. , Sheu Tiffany G. , Xu Xiyan , Klimov Alexander I. , Gubareva Larisa V.
Published: March 2010

The clinical use of the neuraminidase inhibitor (NAI) oseltamivir is associated with the emergence of drug resistance resulting from subtype-specific neuraminidase (NA) mutations. The influenza A/Texas/12/2007 (H3N2) virus isolated from an oseltamivir-treated immunocompromised patient exhibited reduced susceptibility to oseltamivir in the chemiluminescent neuraminidase inhibition (NI) assay (∼60-fold increase in its 50% inhibitory concentration [IC50] compared to that for a control virus). When further propagated in cell culture, the isolate maintained reduced susceptibility to oseltamivir in both chemiluminescent and fluorescent NI assays (∼50- and 350-fold increases in IC50, respectively). Sequencing analysis of the isolate revealed a mix of nucleotides coding for amino acids at position 119 of the NA [E119(V/I)]. Plaque purification of the isolate yielded E119V and E119I variants, both exhibiting reduced susceptibility to oseltamivir. The E119I variant also showed decreased susceptibility to zanamivir and the investigational NAIs peramivir and A-315675. The emergence of E119V variants in oseltamivir-treated patients has been previously reported; however, the E119I mutation detected here is a novel one which reduces susceptibility to several NAIs. Both mutations were not detected in unpropagated original clinical specimens using either conventional sequencing or pyrosequencing, suggesting that these variants were present in very low proportions (<10%) in clinical specimens and gained dominance after virus propagation in MDCK cells. All virus isolates recovered from the patient were resistant to adamantanes. Our findings highlight the potential for emergence and persistence of multidrug-resistant influenza viruses in oseltamivir-treated immunocompromised subjects and also highlight challenges for drug resistance diagnosis due to the genetic instability of the virus population upon propagation in cell culture.
The 6-Aminoquinolone WC5 Inhibits Human Cytomegalovirus Replication at an Early Stage by Interfering with the Transactivating Activity of Viral Immediate-Early 2 Protein
Authors: Loregian Arianna , Mercorelli Beatrice , Muratore Giulia , Sinigalia Elisa , Pagni Silvana , Massari Serena , Gribaudo Giorgio , Gatto Barbara , Palumbo Manlio , Tabarrini Oriana , Cecchetti Violetta , Palù Giorgio
Published: March 2010

WC5 is a 6-aminoquinolone that potently inhibits the replication of human cytomegalovirus (HCMV) but has no activity, or significantly less activity, against other herpesviruses. Here we investigated the nature of its specific anti-HCMV activity. Structure-activity relationship studies on a small series of analogues showed that WC5 possesses the most suitable pattern of substitutions around the quinolone scaffold to give potent and selective anti-HCMV activity. Studies performed to identify the possible target of WC5 indicated that it prevents viral DNA synthesis but does not significantly affect DNA polymerase activity. In yield reduction experiments with different multiplicities of infection, the anti-HCMV activity of WC5 appeared to be highly dependent on the viral inoculum, suggesting that WC5 may act at an initial stage of virus replication. Consistently, time-of-addition and time-of-removal studies demonstrated that WC5 affects a phase of the HCMV replicative cycle that precedes viral DNA synthesis. Experiments to monitor the effects of the compound on virus attachment and entry showed that it does not inhibit either process. Evaluation of viral mRNA and protein expression revealed that WC5 targets an event of the HCMV replicative cycle that follows the transcription and translation of immediate-early genes and precedes those of early and late genes. In cell-based assays to test the effects of WC5 on the transactivating activity of the HCMV immediate-early 2 (IE2) protein, WC5 markedly interfered with IE2-mediated transactivation of viral early promoters. Finally, WC5 combined with ganciclovir in checkerboard experiments exhibited highly synergistic activity. These findings suggest that WC5 deserves further investigation as a candidate anti-HCMV drug with a novel mechanism of action.
Antigen-Presenting Dendritic Cells Rescue CD4-Depleted CCR2−/−Mice from LethalHistoplasma capsulatumInfection
Authors: Szymczak Wendy A. , Deepe George S.
Published: March 2010

Excessive production of interleukin-4 impairs clearance of the fungal pathogenHistoplasma capsulatumin mice lacking the chemokine receptor CCR2. An increase in the interleukin-4 level is associated with decreased recruitment of dendritic cells to lungs; therefore, we investigated the possibility that these cells influence interleukin-4 production. Adoptive transfer of wild-type or CCR2−/−bone marrow-derived dendritic cells loaded with heat-killed yeast cells to infected CCR2−/−mice suppressed interkeukin-4 transcription. Surprisingly, transfer of cells did not reduce the fungal burden despite the fact that it limited interleukin-4 transcription. Yeast cell-loaded bone marrow-derived dendritic cell-mediated regulation of interleukin-4 transcription was dependent on major histocompatibility complex II antigen presentation to CD4+T cells. We previously showed that CD4+T cells were a source of interleukin-4 in infected CCR2−/−mice, but their contribution to the TH2 phenotype was unclear. Here we demonstrated that these cells were functionally important since elimination of them prior to infection, but not elimination of them at the time of infection, reduced the interleukin-4 level in infected CCR2−/−mice. However, the fungal burden was reduced only in CD4-depleted CCR2−/−mice that received yeast cell-loaded bone marrow-derived dendritic cells. Taken together, the data indicate that generation of excess interleukin-4 in lungs ofH. capsulatum-infected CCR2−/−mice is at least partially a consequence of decreased recruitment of dendritic cells capable of antigen presentation. Furthermore, CD4+T cells had a deleterious impact on immunity in infected CCR2−/−mice.
CdpA Is a
Burkholderia pseudomallei
Cyclic di-GMP Phosphodiesterase Involved in Autoaggregation, Flagellum Synthesis, Motility, Biofilm Formation, Cell Invasion, and Cytotoxicity
Authors: Lee Hwee Siang , Gu Feiyu , Ching Shi Min , Lam Yulin , Chua Kim Lee
Published: March 2010

Cyclic diguanylic acid (c-di-GMP) is an intracellular signaling molecule involved in regulation of cellular functions such as motility, biofilm formation and virulence. Intracellular level of c-di-GMP is controlled through opposing diguanylate cyclase (DGC) and phosphodiesterase (PDE) activities of GGDEF and EAL domain proteins, respectively. We report the identification and characterization of
cdpA
, a gene encoding a protein containing an EAL domain in the Gram-negative soil bacillus and human pathogen
Burkholderia pseudomallei
KHW. Purified recombinant CdpA protein exhibited PDE activity
in vitro
. Evidence that CdpA is a major c-di-GMP-specific PDE in
B. pseudomallei
KHW was shown by an 8-fold-higher c-di-GMP level in the
cdpA-
null mutant as compared to the wild type and the complemented
cdpA
mutant. The presence of higher intracellular c-di-GMP levels in the
cdpA-
null mutant was associated with increased production of exopolysaccharides, increased cell-to-cell aggregation, absence of flagella and swimming motility, and increased biofilm formation. The relevance of CdpA in
B. pseudomallei
virulence was demonstrated by a 3-fold reduction in invasion of human lung epithelial cells and a 6-fold reduction in cytotoxicity on human macrophage cells infected with the
cdpA
mutant.
Inactivation of Phospholipase D DiminishesAcinetobacter baumanniiPathogenesis
Authors: Jacobs Anna C. , Hood Indriati , Boyd Kelli L. , Olson Patrick D. , Morrison John M. , Carson Steven , Sayood Khalid , Iwen Peter C. , Skaar Eric P. , Dunman Paul M.
Published: March 2010

Acinetobacter baumanniiis an emerging bacterial pathogen of considerable health care concern. Nonetheless, relatively little is known about the organism's virulence factors or their regulatory networks. Septicemia and ventilator-associated pneumonia are two of the more severe forms ofA. baumanniidisease. To identify virulence factors that may contribute to these disease processes, genetically diverseA. baumanniiclinical isolates were evaluated for the ability to proliferate in human serum. A transposon mutant library was created in a strain background that propagated well in serum and screened for members with decreased serum growth. The results revealed that disruption ofA. baumanniiphospholipase D (PLD) caused a reduction in the organism's ability to thrive in serum, a deficiency in epithelial cell invasion, and diminished pathogenesis in a murine model of pneumonia. Collectively, these results suggest that PLD is anA. baumanniivirulence factor.
Role of Host Sphingosine Kinase 1 in the Lung Response against Cryptococcosis
Authors: McQuiston Travis , Luberto Chiara , Del Poeta Maurizio
Published: March 2010

Cryptococcus neoformansis a fungal pathogen causing pulmonary infection and a life-threatening meningoencephalitis in human hosts. The fungus infects the host through inhalation, and thus, the host response in the lung environment is crucial for containment or dissemination ofC. neoformansto other organs. In the lung, alveolar macrophages (AMs) are key players in the host lung immune response, and upon phagocytosis, they can killC. neoformansby evoking an effective immune response through a variety of signaling molecules. On the other hand, under conditions not yet fully defined, the fungus is able to survive and proliferate within macrophages. Since the host sphingosine kinase 1 (SK1) regulates many signaling functions of immune cells, particularly in macrophages, in this study we determined the role of SK1 in the host response toC. neoformansinfection. Using wild-type (SK1/2+/+) and SK1-deficient (SK1−/−) mice, we found that SK1 is dispensable during infection with a facultative intracellular wild-typeC. neoformansstrain. However, SK1 is required to form a host lung granuloma and to prevent brain infection by aC. neoformansmutant strain lacking the cell wall-associated glycosphingolipid glucosylceramide (Δgcs1), previously characterized as a mutant able to replicate only intracellularly. Specifically, in contrast to those from SK1/2+/+mice, lungs from SK1−/−mice have no collagen deposition upon infection withC. neoformansΔgcs1, and AMs from these mice contain significantly moreC. neoformanscells than AMs from SK1/2+/+mice, suggesting that under conditions in whichC. neoformansis more internalized by AMs, SK1 may become important to controlC. neoformansinfection. Indeed, when we induced immunosuppression, a host condition in which wild-typeC. neoformanscells are increasingly found intracellularly, SK1−/−survived significantly less than SK1/2+/+mice infected with a facultative intracellular wild-type strain, suggesting that SK1 has an important role in controllingC. neoformansinfection under conditions in which the fungus is predominantly found intracellularly.
A DETAIL ANALYSIS OF ELECTRICAL AND OPTICAL FLUCTUATIONS OF GREEN LIGHT-EMITTING DIODES BY CORRELATION METHOD
Authors: PALENSKIS VILIUS , MATUKAS JONAS , PRALGAUSKAITĖ SANDRA , SAULYS BRONIUS
Published: March 2010

A detail analysis of electrical and optical fluctuations of large power (1 W) green light-emitting diodes (LEDs) is presented. Special attention was directed to measurement and interpretation of correlation coefficient between electrical and optical fluctuations. The correlation coefficient was measured not only over frequency range from 10 Hz to 20 kHz, but also in every one-octave frequency band by using digital filters. It is shown that correlated part of electrical and optical fluctuations for investigated green LEDs is related with random potential fluctuations of parameters of quantum well due to charge carrier capture by the defects in the active layer, while uncorrelated part of electrical noise is caused by parallel leakage channel which resistance is many times higher than that of p-n junction.
Engineering the web's third decade
Authors: Kroeker Kirk L.
Published: March 2010

As Web technologies move beyond two-way interactive capabilities to facilitate more dynamic and pervasive experiences, the Web is quickly advancing toward its third major upgrade.
Gaming will save us all
Authors: Chang Tim
Published: March 2010

How gaming, as the first media market to successfully transition toward media-as-a-service, is an exemplar for a similar evolutionary transition of content and entertainment.
Only technological processes are patentable
Authors: Samuelson Pamela
Published: March 2010

The U.S. Supreme Court will narrow the universe of process innovations that can be patented to those that are "technological," but what will that mean for software?
Orchestrating coordination in pluralistic networks
Authors: Denning Peter J. , Flores Fernando , Luzmore Peter
Published: March 2010

Learning to build virtual teams of people of diverse backgrounds is an urgent challenge.
Toward energy-efficient computing
Authors: Brown David J. , Reams Charles
Published: March 2010

What will it take to make server-side computing more energy efficient?
Virtual computing initiative at a small public university
Authors: Seay Cameron , Tucker Gary
Published: March 2010

Student participation and resulting expertise is as valuable as having the high-performance resource itself.
Global IT management
Authors: Sia Siew Kien , Soh Christina , Weill Peter
Published: March 2010

To succeed on a global scale, businesses should focus on a trio of key elements.
Practitioner-based measurement
Authors: Parkinson S. T. , Hierons R. M. , Lycett M. , Norman M.
Published: March 2010

Introduction

The established philosophy within the software development industry is that an organization implementing a program to improve software quality can expect to recoup the cost of the implementation many times over through the reduced cost associated with improvements in quality. Measurement initiatives are perceived to provide a key contribution to quality improvement as evidenced by the focus of early measurement based initiatives and the place of measurement in the higher echelons of process initiatives. In general, organizations pursue measurement initiatives from a perspective that, without measurement, control is not possible. While organizations recognize that there are potential benefits to measuring their processes and products, however, they typically find it difficult to structure ad-hoc measures into a formal program -- a situation that is compounded by the significant cost of implementing such programs. Although these problems have led to some organizations moving away from measurement programs, many companies still use measurement programs as illustrated by the continued interest in, for example, the Capability Maturity Model. Given the appetite and potential returns on investment of measurement frameworks and initiatives, ways of successfully implementing them are important.

With that importance in mind, this work evaluates the implementation of such a measurement framework in a major Insurance organization. A hybrid model -- practitioner-based -- was devised to incorporate the best aspects of current approaches and mitigate identified shortcomings. In order to continually improve software quality, research was conducted to understand the critical success factors in implementing software measurement programs, develop a measurement framework to address the critical success factors, implement a pilot program based on that framework, and reflect on the outcomes of implementation for future practice. We examine existing measurement frameworks in order to assess the critical success factors and the relative strengths and weaknesses of existing approaches in relation to those factors and describe the model that results from the outcomes of the analysis of strengths and weaknesses of existing approaches. Later, we describe the implementation of a pilot of the model in an established IT department and evaluate the success of the pilot and the implications for the state-of-the-art.
Modeling time in computing
Authors: Furia Carlo A. , Mandrioli Dino , Morzenti Angelo , Rossi Matteo
Published: March 2010

The increasing relevance of areas such as real-time and embedded systems, pervasive computing, hybrid systems control, and biological and social systems modeling is bringing a growing attention to the temporal aspects of computing, not only in the computer science domain, but also in more traditional fields of engineering.

This article surveys various approaches to the formal modeling and analysis of the temporal features of computer-based systems, with a level of detail that is also suitable for nonspecialists. In doing so, it provides a unifying framework, rather than just a comprehensive list of formalisms.

The article first lays out some key dimensions along which the various formalisms can be evaluated and compared. Then, a significant sample of formalisms for time modeling in computing are presented and discussed according to these dimensions. The adopted perspective is, to some extent, historical, going from “traditional” models and formalisms to more modern ones.
A survey of techniques for achieving metadata interoperability
Authors: Haslhofer Bernhard , Klas Wolfgang
Published: March 2010

Achieving uniform access to media objects in heterogeneous media repositories requires dealing with the problem of metadata interoperability. Currently there exist many interoperability techniques, with quite varying potential for resolving the structural and semantic heterogeneities that can exist between metadata stored in distinct repositories. Besides giving a general overview of the field of metadata interoperability, we provide a categorization of existing interoperability techniques, describe their characteristics, and compare their quality by analyzing their potential for resolving various types of heterogeneities. Based on our work, domain experts and technicians get an overview and categorization of existing metadata interoperability techniques and can select the appropriate approach for their specific metadata integration scenarios. Our analysis explicitly shows that metadata mapping is the appropriate technique in integration scenarios where an agreement on a certain metadata standard is not possible.
Fusion of threshold rules for target detection in wireless sensor networks
Authors: Zhu Mengxia , Ding Song , Wu Qishi , Brooks R. R. , Rao N. S. V. , Iyengar S. S.
Published: March 2010

We propose a binary decision fusion rule that reaches a global decision on the presence of a target by integrating local decisions made by multiple sensors. Without requiring a priori probability of target presence, the fusion threshold bounds derived using Chebyshev's inequality ensure a higher hit rate and lower false alarm rate compared to the weighted averages of individual sensors. The Monte Carlo-based simulation results show that the proposed approach significantly improves target detection performance, and can also be used to guide the actual threshold selection in practical sensor network implementation under certain error rate constraints.
Speeding-up heuristic allocation, scheduling and binding with SAT-based abstraction/refinement techniques
Authors: Cabodi Gianpiero , Lavagno Luciano , Murciano Marco , Kondratyev Alex , Watanabe Yosinori
Published: March 2010

Hardware synthesis is the process by which system-level, Register Transfer (RT)-level, or behavioral descriptions can be turned into real implementations, in terms of logic gates. Scheduling is one of the most time-consuming steps in the overall design flow, and may become much more complex when performing hardware synthesis from high-level specifications. Exploiting a single scheduling strategy on very large designs is often reductive and potentially inadequate. Furthermore, finding the “best” single candidate among all possible scheduling algorithms is practically infeasible. In this article we introduce a hybrid scheduling approach that is a preliminary step towards a comprehensive solution not yet provided by industrial or by academic solutions. Our method relies on an abstract symbolic representation of data flow nodes (operations) bound to control flow paths: it produces a more realistic lower bound during the prescheduling resource estimation step and speeds up slower but accurate heuristic scheduling techniques, thus achieving a globally improved result.
Hardware/software partitioning and pipelined scheduling on runtime reconfigurable FPGAs
Authors: Yuan Mingxuan , Gu Zonghua , He Xiuqiang , Liu Xue , Jiang Lei
Published: March 2010

FPGAs are widely used in today's embedded systems design due to their low cost, high performance, and reconfigurability. Partially RunTime-Reconfigurable (PRTR) FPGAs, such as Virtex-2 Pro and Virtex-4 from Xilinx, allow part of the FPGA area to be reconfigured while the remainder continues to operate without interruption, so that HW tasks can be placed and removed dynamically at runtime. We address two problems related to HW task scheduling on PRTR FPGAs: (1) HW/SW partitioning. Given an application in the form of a task graph with known execution times on the HW (FPGA) and SW (CPU), and known area sizes on the FPGA, find an valid allocation of tasks to either HW or SW and a static schedule with the optimization objective of minimizing the total schedule length (makespan). (2) Pipelined scheduling. Given an input task graph, construct a pipelined schedule on a PRTR FPGA with the goal of maximizing system throughput while meeting a given end-to-end deadline. Both problems are NP-hard. Satisfiability Modulo Theories (SMT) is an extension to SAT by adding the ability to handle arithmetic and other decidable theories. We use the SMT solver Yices with Linear Integer Arithmetic (LIA) theory as the optimization engine for solving the two scheduling problems. In addition, we present an efficient heuristic algorithm based on kernel recognition for the pipelined scheduling problem, a technique borrowed from SW pipelining, to overcome the scalability problem of the SMT-based optimal solution technique.
Thermal analysis of multiprocessor SoC applications by simulation and verification
Authors: Das Dipankar , Chakrabarti P. P. , Kumar Rajeev
Published: March 2010

Overheating of computer chips leads to degradation of performance and reliability. Therefore, preventing chips from overheating in spite of increased performance requirements has emerged as a major challenge. Since the cost of cooling has been rising steadily, various architecture and application design techniques are used to prevent chip overheating. Temperature-aware task scheduling has emerged as an important application design methodology for addressing this problem in multiprocessor SoC systems.

In this work we present the formulation and implementation of a method for analyzing the thermal (chip heating) behavior of a MPSoC task schedule, during the early stages of the design. We highlight the challenges in developing such a framework and propose solutions for tackling them. Due to nondeterminism in task execution times and decision branches, multiprocessor applications cannot be evaluated accurately by the current state-of-the-art
thermal
simulation
and
steady-state
analysis methods. Hence an analysis covering nondeterministic execution behaviors is required for thermal analysis of MPSoC task schedules. To address this issue we propose a model checking-based approach for solving the thermal analysis problem and formulate it as a hybrid automata reachability verification problem. We present an algorithm for constructing this hybrid automata given the task schedule, a set of power profiles of tasks, and the Compact Thermal Model (CTM) of the chip. Information about task power consumption is inferred from Markov chains which are learned from power profiles of tasks, obtained from simulation or emulation runs. A numerical analysis-based algorithm which uses CounterExample-Guided Abstraction Refinement (CEGAR) is developed for reachability analysis of this hybrid automata. We propose a directed simulation methodology which uses results of a time-bounded analysis of the hybrid automata modeling thermal behavior of the application, to simulate the expected worst-case execution runs of the same. The algorithms presented in this work have been implemented in a prototype tool called
HeatCheck
. We present experimental results and analysis of thermal behavior of a set of task schedules executing on a MPSoC system.
Phase-adjustable error detection flip-flops with 2-stage hold-driven optimization, slack-based grouping scheme and slack distribution control for dynamic voltage scaling
Authors: Kurimoto Masanori , Suzuki Hiroaki , Akiyama Rei , Yamanaka Tadao , Ohkuma Haruyuki , Takata Hidehiro , Shinohara Hirofumi
Published: March 2010

For Dynamic Voltage Scaling (DVS), we propose a novel design methodology. This methodology is composed of an error detection circuit and three technologies to reduce the area and power penalties which are the large issues for the conventional DVS with error detection. The proposed circuit, Phase-Adjustable Error Detection Flip-Flip (PEDFF), adjusts the clock phase of an additional FF for the timing error detection, based on the timing slack. 2-Stage Hold-Driven Optimization (2-SHDO) technology splits the hold-driven optimization in two stages. Slack-Based Grouping Scheme (SBGS) technology divides each timing path into appropriate groups based on the timing slack. Slack Distribution Control (SDC) technology improves the sharp distribution of the path delay at which the logic synthesis tool has relaxed the delay. We evaluate the methodology by simulating a 32-bit microprocessor in 90 nm CMOS technology. The proposed methodology reduces the energy consumption by 19.8% compared to non-DVS. The OR-tree's latency is shortened to 16.3% compared to the conventional DVS. The area and power penalties for delay buffers on short paths are reduced to 35.0% and 40.6% compared to the conventional DVS, respectively. The proposed methodology with SDC reduces the energy consumption by 17.0% on another example with the sharp slack distribution by the logic synthesis compared to non-DVS.
Coscheduling of processor voltage and control task period for energy-efficient control systems
Authors: Lee Hyung Sun , Kim Byung Kook
Published: March 2010

The Dynamic Voltage Scaling (DVS) technique has been widely studied for energy-constrained real-time systems; however, its application to control systems has not been studied in a variety of aspects. This article presents a novel method to simultaneously schedule processor voltage and control-task periods online, considering energy-efficiency of control systems as a whole. A new performance index is proposed, which contains both control performance and processor energy terms. Then, an online scheduler assigning processor voltage and control-task periods that maximizes the performance index is proposed. The performance of the proposed scheduler under varying control workload is verified using MATLAB simulations and experiments on an actual DVS hardware platform.
A robust seamless communication architecture for next-generation mobile terminals on multi-CPU SoCs
Authors: Inoue Hiroaki , Sakai Junji , Edahiro Masato
Published: March 2010

We propose a robust seamless communication architecture that enables legacy mobile terminal software designed for single-CPU processors to be run on multi-CPU processors without any software modifications. This architecture features two new technologies: proxy processes, which help achieve the design of its user-level system-call hooking and a robust design method, which reduces bandwidth variation by systematic parameter optimization. Our evaluations confirmed that this architecture achieves fundamental features with satisfactory performance, that we have succeeded in getting actual mobile terminal software to run on three CPUs without modifying the software, and that the robust design method reduces bandwidth variation by 21%.