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Hegel is not an author who plays a starring role in Cavell’s work like that of Austin, Wittgenstein, or Emerson. Cavell mentions him rarely, and almost always in passing. This is hardly surprising. Given that Cavell draws as heavily as he does upon Kant, whom Hegel regularly attacks, and Kierkegaard, who regularly attacks Hegel, one might expect that Hegel’s more important claims and ideas would be uncongenial to Cavell, and incompatible with the main lines of his work. Moreover, Cavell’s early and lasting embrace of Romanticism would seem to preclude the embrace of an author who lambasts the leading Jena Romantic Friedrich von Schlegel as the purveyor of a corrosive amoral subjectivism. Appearances, however, can be deceiving, and in the essay that follows I demonstrate that there are good reasons to believe that Hegel has influenced Cavell considerably more than one might suppose.

Homo-oligomeric ligand-activated proteins are ubiquitous in biology. The functions of such molecules are commonly regulated by allosteric coupling between ligand-binding sites. Understanding the basis for this regulation requires both quantifying the free energy ΔG transduced between sites, and the structural basis by which it is transduced. We consider allostery in three variants of the model ring-shaped homo-oligomeric trp RNA-binding attenuation protein (TRAP). First, we developed a nearest-neighbor statistical thermodynamic binding model comprising microscopic free energies for ligand binding to isolated sites ΔG

The phrase, “epistemology of moods,” appears in Stanley Cavell’s writings in the late 1970’s, as The Claim of Reason is published and Cavell begins the direct engagement with Emerson around which his work will pivot for the rest of his career. Indeed, it is as an “epistemologist of moods” that Emerson first appeals to Cavell in his own right, and not as merely a “second-hand Thoreau.” The phrase is an odd one. Most of us would not think that knowledge and mood are connected in the way it suggests: my foul mood may make it difficult for me to concentrate on, say, my taxes, but it does not appear to otherwise affect my ability to know how much or how little I owe—and the same could be said of Sextus’ honey, Descartes’ ball of wax, Price’s tomato, and Clarke’s block of cheese. The oddity of the phrase is, if anything, even more marked when coming from Cavell: though Cavell is deeply interested in questions of self-knowledge, and of our ability to speak for one another and in that sense know one another, he is not an epistemologist; and when he writes of epistemology he often uses phrases like traditional epistemology or classical epistemology that distance him from it. Cavell does not share the traditional epistemologist’s interest in determining what, if anything, might warrant our claims to knowledge of the empirical world or the existence of “other minds”; and “the truth of skepticism” that he announces and explores is not the truth of the claims of the epistemological skeptic regarding such matters. While the epistemologist seeks to assure himself of the certainty of his knowledge, Cavell seeks to understand our disappointment with the knowledge we have. What, then, does Cavell mean by this phrase? What is the epistemology of moods?

BX1 from Zea mays (zmBX1) is an enzyme of plant secondary metabolism that generates indole for the synthesis of plant defensins. It is a homologue of the tryptophan synthase α-subunit, TrpA. Whereas TrpA itself is a monomer in solution, zmBX1 is dimeric, confirmed in our work by native MS. Using cross-linking and mutagenesis, we identified the physiological dimerization interface of zmBX1. We found that homodimerization has only minor effects on catalysis and stability. A comparison of the zmBX1-zmBX1 homodimer and zmTrpA-zmTrpB heterodimer interfaces suggest that homodimerization in zmBX1 might, at an early point in evolution, have served as a mechanism to exclude the interaction with the tryptophan synthase β-subunit (zmTrpB), marking its transition from primary to secondary metabolism.

Degradation of instream habitats in the northern Murray–Darling Basin has occurred through numerous stressors, including siltation, clearing of bankside vegetation, intrusion of livestock and impacts of pest species. A better understanding of habitat preferences of native fish species could help guide future instream habitat restoration actions. The habitat choices of seven native fish species, juvenile Murray Cod (Maccullochella peelii), juvenile Golden Perch (Macquaria ambigua ambigua), juvenile Silver Perch (Bidyanus bidyanus), adult Murray–Darling Rainbowfish (Melanotaenia fluviatilis), adult Olive Perchlet (Ambassis agassizii), adult Un‐specked Hardyhead (Craterocephalus stercusmuscarum fulvus) and adult carp gudgeons (Hypseleotris spp.) were tested in preference troughs to help inform potential habitat restoration actions in the Condamine catchment. Each species was given a choice between pair combinations of open sandy habitat, submerged macrophytes, emergent plants and rocky rubble. Habitat preferences varied between species. Murray Cod, Golden Perch, carp gudgeons and Olive Perchlets preferred structure over open sandy habitat, whilst juvenile Silver Perch, Un‐specked Hardyhead and Murray–Darling Rainbowfish did not avoid open sandy habitats. Juvenile Murray Cod preferred rocky rubble habitat over all other habitat choices. Use of complex rock piles to provide nursery habitat for Murray Cod populations is a potential restoration option. Introduction of rock could also benefit Golden Perch and carp gudgeons. Use of emergent plants, submerged macrophytes and rocky rubble for habitat restoration all appear to have merit for one or more species of small‐bodied fishes or juvenile stages of larger sized fishes. Rocky rubble or floating attached macrophytes could be viable restoration options in areas too turbid to establish submerged macrophytes. These habitat interventions would complement existing actions such as re‐snagging and provision of fish passage to assist with sustainable management of native fish populations.

Mechanistic understanding of the structural basis for DNA recombination in the Cre-loxP system has largely been guided by crystallographic structures of tetrameric synaptic complexes (intasomes). These structural and biochemical studies have suggested that conformational changes and DNA bending in presynaptic complexes underlie site-selection and activation mechanisms of Cre recombinase. Here we used protein engineering and various DNA substrates to isolate the Cre-loxP (54 kDa), Cre2-loxP (110 kDa), and Cre4-loxP2 assembly intermediates, and determined their structures using cryo-EM to resolutions of 3.9 Å, 4.5 Å, and 3.2 Å, respectively. Progressive DNA bending along the assembly pathway enables formation of increasingly intimate protein-protein interfaces. Insufficient stabilization of important protein motifs observed during the assembly process provides a compelling explanation for the observed half-the-sites activity, and preferential bottom strand cleavage of loxP sequences. We found that selection of loxP sites is largely dependent on Cre’s ability to bend and stabilize the spacer region between two recombinase binding elements. Application of 3D variability analysis to the tetramer data reveals a propensity for motion along the pathway between protomer activation and Holliday junction isomerization. These findings help us to better understand loxP site specificity, controlled activation of alternating protomers, the basis for the observed bias of strand cleavage order, and the importance of conformational sampling, especially with regards to site-selection and activity among Cre variants. Furthermore, our findings provide invaluable information for the rational development of designer, site-specific recombinases for use as gene editing technologies.HighlightsCryo-EM structures of Cre-loxP assembly intermediates (monomer, dimer, and tetramer) provide insights into mechanisms of site recognition, half-the-sites activity, strand cleavage order, and concerted strand cleavageSelectivity of loxP sites arises from few base-specific contacts made by each protomer and is mainly driven by formation of phosphate contacts and DNA deformations that are maximal in the fully assembled “active” tetramerCis and trans interactions of the β2-3 loop (i) define which sites are “active” and (ii) ensure half-the-sites activityProtein flexibility plays a central role in enabling DNA sequence scanning, recruitment of a second protein to form a dimer, synapsis, control of activity, as well as subsequent recombination stepsConformational sampling within the tetrameric complex was uncovered using 3D variability analysis and revealed the importance of protein-protein interfaces for site- selection and activation of Cre-loxP complexes

Redβ is a single strand annealing protein from bacteriophage λ that binds loosely to ssDNA, not at all to pre-formed dsDNA, but tightly to a duplex intermediate of annealing. As viewed by electron microscopy, Redβ forms oligomeric rings on ssDNA substrate, and helical filaments on the annealed duplex intermediate. However, it is not clear if these are the functional forms of the protein in vivo. We have used size-exclusion chromatography coupled with multi-angle light scattering, analytical ultracentrifugation and native mass spectrometry (nMS) to characterize the size of the oligomers formed by Redβ in its different DNA-bound states. The nMS data, which resolve species with the highest resolution, reveal that Redβ forms an oligomer of 12 subunits in the absence of DNA, complexes ranging from 4 to 14 subunits on 38-mer ssDNA, and a much more distinct and stable complex of 11 subunits on 38-mer annealed duplex. We also measure the concentration of Redβ in cells active for recombination and find it to range from 7 to 27 μM. Collectively, these data provide new insights into the dynamic nature of the complex on ssDNA, and the more stable and defined complex on annealed duplex.

Purification of recombinant proteins typically entails overexpression in heterologous systems and subsequent chromatography-based isolation. While denaturing sodium dodecyl sulfate-polyacrylamide gel electrophoresis is routinely used to screen a variety of overexpression conditions (e.g., host, medium, inducer concentration, post-induction temperature and/or incubation time) and to assess the purity of the final product, its limitations, including aberrant protein migration due to compositional eccentricities or incomplete denaturation, often preclude firm conclusions regarding the extent of overexpression and/or purification. Therefore, we recently reported an automated liquid chromatography-mass spectrometry-based strategy that couples immobilized metal affinity chromatography (IMAC) with size exclusion-based online buffer exchange (OBE) and native mass spectrometry (nMS) to directly analyze cell lysates for the presence of target proteins. IMAC-OBE-nMS can be used to assess whether target proteins (1) are overexpressed in soluble form, (2) bind and elute from an IMAC resin, (3) oligomerize, and (4) have the expected mass. Here, we use four poly-His-tagged proteins to demonstrate the potential of IMAC-OBE-nMS for expedient optimization of overexpression and purification conditions for recombinant protein production.

Actin is an essential element of both innate and adaptive immune systems and can aid in motility and translocation of bacterial pathogens, making it an attractive target for bacterial toxins. Pathogenic Vibrio and Aeromonas genera deliver actin cross-linking domain (ACD) toxin into the cytoplasm of the host cell to poison actin regulation and promptly induce cell rounding. At early stages of toxicity, ACD covalently cross-links actin monomers into oligomers (AOs) that bind through multivalent interactions and potently inhibit several families of actin assembly proteins. At advanced toxicity stages, we found that the terminal protomers of linear AOs can get linked together by ACD to produce cyclic AOs. When tested against formins and Ena/VASP, linear and cyclic AOs exhibit similar inhibitory potential, which for the cyclic AOs is reduced in the presence of profilin. In coarse-grained molecular dynamics simulations, profilin and WH2-motif binding sites on actin subunits remain exposed in modeled AOs of both geometries. We speculate, therefore, that the reduced toxicity of cyclic AOs is due to their reduced configurational entropy. A characteristic feature of cyclic AOs is that, in contrast to the linear forms, they cannot be straightened to form filaments (e.g., through stabilization by cofilin), which makes them less susceptible to neutralization by the host cell.

The ubiquitous ribonucleoprotein (RNP) form of RNase P catalyzes the Mg(2+)-dependent cleavage of the 5′ leader of precursor-transfer RNAs. The rate and fidelity of the single catalytic RNA subunit in the RNase P RNP is significantly enhanced by association with protein cofactors. While the bacterial RNP exhibits robust activity at near-physiological Mg(2+) concentrations with a single essential protein cofactor, archaeal and eukaryotic RNase P are dependent on up to five and ten protein subunits, respectively. Archaeal RNase P–whose proteins share eukaryotic homologs–is an experimentally tractable model for dissecting in a large RNP the roles of multiple proteins that aid an RNA catalyst. We describe protocols to assemble RNase P from Methanococcus maripaludis, a methanogenic archaeon. We present strategies for tag-less purification of four of the five proteins (the tag from the fifth is removed post-purification), an approach that helps reconstitute the RNase P RNP with near-native constituents. We demonstrate the value of native mass spectrometry (MS) in establishing the accurate masses (including native oligomers and modifications) of all six subunits in M. maripaludis RNase P, and the merits of mass photometry (MP) as a complement to native MS for characterizing the oligomeric state of protein sub-complexes. We showcase the advantage of native MS and MP over SDS-PAGE in revealing time-dependent modifications (e.g., oxidation) and aggregation of protein subunits, thereby providing insights into the decreased function of RNase P assembled with aged preparations of recombinant subunits. Our protocols and cautionary findings are applicable to studies of other cellular RNPs.

BX1 from Zea mays (zmBX1) is an enzyme of plant secondary metabolism that generates indole for the synthesis of plant defensins. It is a homolog of the tryptophan synthase α-subunit, TrpA. Whereas TrpA itself is a monomer in solution, zmBX1 is dimeric, confirmed in our work by native MS. Using cross-linking and mutagenesis, we identified the physiological dimerization interface of zmBX1. We found that homodimerization has only minor effects on catalysis and stability. A comparison of the zmBX1–zmBX1 homodimer and zmTrpA–zmTrpB heterodimer interfaces suggest that homodimerization in zmBX1 might, at an early point in evolution, have served as a mechanism to exclude the interaction with the tryptophan synthase β-subunit (zmTrpB), marking its transition from primary to secondary metabolism.

The manuscript describes the use of chemical cross-linking/mass spectrometry and mutagenesis to investigate the dimeric interface of the tryptophan synthase α-subunit homolog, BX1. This work indicates that BX1 homodimerization might have served as a mechanism to exclude an interaction with the tryptophan synthase β-subunit, TrpB, at an early time in evolution, thereby eliminating cross-talk between primary and secondary metabolism. This work would be of interest to mass spectrometrists and structural biologist as it presents a workflow to determine the physiological protein-protein interactions within crystal structures using chemical cross-linking/mass spectrometry and mutagenesis as complementary structural biology techniques, thereby eliminating ambiguity and potential mis-assignments due to the presence of additional (artificial) protein contacts formed during the crystallization process.

Graphene is a suitable substrate to study organic films due to the chemical stability of graphene derived from its structure and the low density of states around the Fermi level (Dirac point for neutral graphene). These two characteristics result in a reduced perturbation on the adsorbed molecules. There are few examples showing the unperturbed frontier molecular orbitals for individual molecules adsorbed on graphene or the formation of unperturbed intermolecular bands in self-assembled molecular overlayers. Simultaneously noncovalent functionalization using molecules has been suggested as a means of tailoring graphene’s band structure without compromising its overall excellent electron properties.

The higher the energy of a particle is above equilibrium, the faster it relaxes because of the growing phase space of available electronic states it can interact with. In the relaxation process, phase coherence is lost, thus limiting high-energy quantum control and manipulation. In one-dimensional systems, high relaxation rates are expected to destabilize electronic quasiparticles. Here, we show that the decoherence induced by relaxation of hot electrons in one-dimensional semiconducting nanowires evolves nonmonotonically with energy such that above a certain threshold hot electrons regain stability with increasing energy. We directly observe this phenomenon by visualizing, for the first time, the interference patterns of the quasi-one-dimensional electrons using scanning tunneling microscopy. We visualize the phase coherence length of the one-dimensional electrons, as well as their phase coherence time, captured by crystallographic Fabry-Pèrot resonators. A remarkable agreement with a theoretical model reveals that the nonmonotonic behavior is driven by the unique manner in which one-dimensional hot electrons interact with the cold electrons occupying the Fermi sea. This newly discovered relaxation profile suggests a high-energy regime for operating quantum applications that necessitate extended coherence or long thermalization times, and may stabilize electronic quasiparticles in one dimension.

‘Demonstration reaches’ are sections of river where multiple threats to native fish are addressed through river rehabilitation and strong community participation. They are an important way of promoting the key driving actions of the Murray-Darling Basin Authority's Native Fish Strategy (NFS) by using on-ground community-driven rehabilitation. Measuring rehabilitation success against well-defined targets and using this information to adaptively mange activities is fundamental to the demonstration reach philosophy. Seven years on from the establishment of the first demonstration reach, there are now seven throughout the Murray-Darling Basin (MDB), all in differing states of maturation and but all applying a standardised framework for monitoring native fish outcomes. In this study, we reflect on the role that demonstration reaches have played within the NFS, synthesise some key findings from 32 monitoring and evaluation outputs, and highlight some of the successes and barriers to success. We make recommendations as to how to strengthen the demonstration reach model to ensure it remains a relevant approach for fish habitat rehabilitation beyond the NFS and MDB.

By pulsing the tunneling voltage between the Tungsten (W) tip of a Scanning Tunneling Microscope (STM) and a graphene-covered metal surface, a superconducting (SC) nanostructure is formed at the apex of the STM tip. We have characterized the SC properties of the resulting nanotip as a function of temperature and magnetic field, obtaining a transition temperature of 3.3 K and a critical field well above 3 T. The SC nanotip is robust and stable and achieves atomic resolution. A non-SC tip can be easily recovered by controlled voltage pulsing on a clean metal surface. The present result should be taken into account when studying zero-bias features like Kondo resonances, zero-bias-conductance peaks, or superconductivity on graphene-based systems by means of STM using tungsten tips.

Objective: To develop a compact probe that can be used to monitor humidity in ventilator care equipment. A mesoporous film of alternate layers of Poly(allylamine hydrochloride) (PAH) and silica (SiO2) nanoparticles (bilayers), deposited onto an optical fibre was used. The sensing film behaves as a Fabry-Perot cavity of low-finesse where the absorption of water vapour changes the optical thickness and produces a change in reflection proportional to humidity. Methods: The mesoporous film was deposited upon the cleaved tip of an optical fibre using the layer-by-layer method. The sensor was calibrated in a bench model against a commercially available capacitive sensor. The sensitivity and response time were assessed in the range from 5 % relative humidity (RH) to 95%RH for different numbers of bilayers up to a maximum of nine. Results: The sensitivity increases with the number of bilayers deposited; sensitivity of 2.28 mV/%RH was obtained for nine bilayers. The time constant of the response was 1.13 s ± 0.30 s which is faster than the commercial device (measured as 158 s). After calibration, the optical fibre humidity sensor was utilised in a bench top study employing a mechanical ventilator. The fast response time enabled changes in humidity in individual breaths to be resolved. Conclusion: Optical fibre sensors have the potential to be used to monitor breath to breath humidity during ventilator care. Significance: Control of humidity is an essential part of critical respiratory care and the developed sensor provides a sensitive, compact and fast method of humidity monitoring.

The disruption of endocrine systems due to environmental contaminants potentially impacts on developmental, behavioural, regulatory, and reproductive systems of wildlife. A major source of exposure of wildlife (terrestrial and aquatic) to endocrine disrupting compounds is through contact with contaminated surface waters. Current testing routines in aquatic systems have not been designed specifically to assess endocrine disruption properties or, alternatively, methods tend not to be fully developed. An alternative approach is to use a response sensitive to these chemicals such as gonopodium length in the pest species Gambusia holbrooki as an indicator. This species was used as a surrogate for native aquatic species to assess endocrine disruption in wetlands that are used for the storage of stormwater or treated sewage effluent. These were compared with adjacent wetlands used for watering stock (farm dams) that were not contaminated with these pollutants. Deformities in the mosquito fish were found that wer...

Alligator weed is a serious weed in many countries. In Australia, it is a “weed of national significance” because of its actual and potential impact. We surveyed all local governments in New South Wales in 2001 and 2007 to determine whether the weed is being contained. We found an increased number and extent of infestations, despite more resources and a better knowledge base. Most considered that further research is needed in tactics for control of the weed. On the basis of current containment in urban gardens, we recommend that governments better mobilize the community (e.g., bush restoration consultants, Landcare groups) to deal with alligator weed infestations.

If political decisionism is the claim that the most important political decisions cannot be regulated by rational norms and instead require a confrontation with the exception, Carl Schmitt remains its most notorious advocate. While Schmitt distanced himself from decisionism when he joined the Nazi party in the 1930s, his critics insist that his role in the events leading to Hitler's assumption of power and his own membership in the party were only attempts "to put... into practice" his earlier theoretical attack on legal positiv ism and what he vaguely termed "liberalism."1 Even for those who reject such sweeping claims, the teaching laid out in his 1922 Political Theology remains deeply disturbing. On Schmitt's account, "Sovereign is he who decides on the exception" [Political Theology 5]. This decision is not a matter of recognizing an exception that already exists; rather it has a performative quality whereby the sovereign decision that names a given event to be an exception is the necessary precondition for the existence of the exception as such?as well as, by extension, the legal system from which it is ex-cepted or removed. The excep tion is, as it were, called into being by the sovereign, whose decision on it is unregulated by the standards of law or, indeed, of normal life itself. The exception is that which cannot be subsumed; it defies general codification, but it simultaneously reveals a specifically juristic element?the decision in its absolute purity. The exception appears in its absolute form when a situation in which legal prescriptions can be valid must first be brought about. Every gen eral norm demands a normal, everyday frame of life to which it can be factually applied and which is subjected to its regulations. The norm requires a homog

A new cytotoxic macrocyclic glycoresin, ipomoeassin F (6), has been isolated from the leaves of Ipomoea squamosa. The structure was elucidated by the interpretation of spectral data. Compound 6 was strongly active in the A2780 (human ovarian cancer cell line) assay with an IC50 value of 0.036 µM. ¶See reference 1.

Carl Schmitt's Political Theology is the locus classicus of contemporary discussions of sovereignty. I argue that Schmitt's conception of sovereignty is excessively metaphysical and that it posits an incoherent 'sovereign’ ability to decide what shall count as normal. Schmitt follows and radicalizes the late Bodin's claims – themselves the product of a political theology, namely, Bodin 's conversion to Judaism – regarding the necessity of an indivisible and absolute sovereignty. In each, the relation between the executive and the other parts of government is reduced to what Schmitt describes as an ‘either/or.’ This move is a disastrous mistake. The question is not whether exceptions and emergencies such as terrorist attacks are real, but to what extent the executive branch can rightly claim a monopoly on the ability to determine whether an exception exists, and whether its resulting actions will be permanently unchecked and unregulated. Recent work by Bruce Ackerman is a better guide in these matters than the metaphysics of either Schmitt or Bodin.

Bioassay-guided fractionation of an extract of the fruit of Macaranga alnifolia from Madagascar led to the isolation of four new prenylated stilbenes, schweinfurthins E−H (1−4), and one new geranylated dihydroflavonol, alnifoliol (5). The known prenylated stilbene vedelianin (6) and the known geranylated flavonoids bonanniol A (7), diplacol (8), bonannione A (9), and diplacone (10) were also isolated. All 10 compounds were tested for antiproliferative activity in the A2780 human ovarian cancer cell line assay. Vedelianin (IC50 = 0.13 μM) exhibited the greatest activity among all isolates, while schweinfurthin E (IC50 = 0.26 μM) was the most potent of the new compounds.

Bioassay-guided fractionation of the cytotoxic leaf and flower extract of Casearia nigrescens led to the isolation of four new clerodane diterpenoids, designated caseanigrescens A-D (1-4). These compounds were subject to hydrolysis to dialdehydes when stored in CDCl3. The structures of compounds 1-4 were determined using 1D and 2D NMR spectroscopy. All four compounds showed moderate cytotoxicity to the A2780 human ovarian cancer cell line, with an IC50 range of 0.83-1.4 microM.

Infections of the ear, nose and throat are common and may threaten life. Intracranial complications may arise from infections of the ear and paranasal sinuses. Orbital complications (loss of vision) may arise from infection of the paranasal sinus. Respiratory embarrassment may result from infections of the upper aerodiogestive tract. The clinical presentation, implications and management of foreign bodies in the ear, nose and throat depend on the nature of the foreign body and the site at which it becomes lodged.

In our continuing search for bioactive molecules from the rainforests of Madagascar as part of an International Cooperative Biodiversity Group (ICBG) program,2 an extract of the leaves of a Madagasacar collection showed moderate cytotoxicity against the A2780 human ovarian cancer cell line. This extract was selected for bioassay-guided fractionation based on its cytotoxicity and its presumed botanical novelty.3 The crude extract was purified by liquid-liquid partition, reversed-phase flash chromatography, and reversed-phased HPLC to yield three new sesquiterpene lactones designated glaucolides K-M. After this work was complete the plant was identified as Vernonia pachyclada Baker (Asteraceae). V. pachyclada is known locally as Tsaboraty, and is used for the treatment of wounds. Members of the Asteraceae family are well known for the production of sesquiterpenes such as the glaucolides, and their presence in the genus Vernonia is particularly well studied.4–9 The genus Vernonia has between 500 and 1,000 species, depending on taxonomic circumscription, with the majority of the species in tropical and warm parts of the Old World, but species are also found in North America. The genus is particularly rich in Madagascar, where nearly 100 species occur, the vast majority of which are endemic.10 Compound 1 was obtained as colorless crystals from methanol. HRFABMS indicated a molecular formula of C23H30O9. The 1H and 13C NMR data (Table 1), the HMQC correlations, and an HMBC experiment (Figure 1) indicated that compound 1 was a sesquiterpene with the same atom connectivity as that of the previously reported compound 8-O-desacetyl confertolide-8-O-methacrylate.11 However, the 1H NMR data for 8-O-desacetyl confertolide-8-O-methacrylate were not in agreement with those of compound 1 when both spectra were determined in the same solvent. Since no 13C NMR or optical rotation data were reported for the literature compound, these data could not be compared. The variations in the 1H NMR data indicated that the compounds are not identical, and suggested that the difference is a stereochemical one. Figure 1 Key HMBC correlations for 1 Table 1 1H and 13C NMR data for compounds 1–3 in CD3OD Therefore, the only remaining problem to solve was that of the stereochemistry of compound 1. The relative stereochemistry was determined based on an analysis of NOESY correlations (Figure 2). The C-15 protons and the C-6 and C-8 protons all correlated to each other, indicating that they have syn-orientations to each other. Also observed were NOESY correlations from the C-15, the C-14, and the C-8 protons to the C-1 proton. Surprisingly a NOESY correlation was also observed between the C-13 protons and the C-9 protons. This correlation was unexpected as the two positions appear to be some distance apart, but in some ring conformations the two positions do appear to be close enough to produce a correlation. Thus, the relative stereochemistry of compound 1 was determined. Figure 2 Key NOESY correlations for 1. During the course of the isolation, crystals of 1 were obtained from methanol. A crystal was thus selected and analyzed by single crystal X-ray diffraction. The results of this experiment confirmed the relative stereochemistry proposed based on the NOESY data and indicated an absolute stereochemistry of 1S,4R,5R,6S,8S,10S, as depicted (Figure 3). The relative stereochemistry for the known compound 8-O-desacetyl confertolide-8-O-methacrylate is 1S, 4R,5S,6S,8S,10R,11 so this compound and 1 differ in relative stereochemistry at C-5 and C-10. The structure was thus assigned as 1, and the compound was named glaucolide K. Figure 3 ORTEP diagram of 1. Compound 2 was obtained as a colorless amorphous solid. HRFABMS indicated a molecular formula of C21H28O8. The 1H and 13C NMR spectra clearly indicated that 2 was an analog of 1. The only significant differences in the 1H NMR data for 2 and 1 were the missing methyl signal at δH 1.99 and the shift of the methylene signal from δH 4.90 and 4.86 in 1 to δH 4.41 (d, J = 12.2 Hz) and 4.38 (d, J = 12.2 Hz) in 2. Thus it appeared as though compound 2 was the C-13 deacetate of 1. This hypothesis was supported by all of the spectral data and confirmed by acetylation of compound 2 to yield compound 1. The structure was thus assigned as 2, and was named glaucolide L. Compound 3 was obtained as a slightly yellow amorphous solid. HRFABMS indicated a molecular formula of C23H30O9. The 1H and 13C NMR spectra indicated that 3 was an analog of 1. No characteristic epoxide signals were observed in the 1H NMR spectrum of 3, and one additional signal was observed for a vinylic proton (δH 6.12, s). The 13C NMR spectrum also contained two additional signals for a C-C double bond. Thus it appeared as though compound 3 was the Δ5 4-hydroxy analog of 1. This hypothesis was supported by HMBC correlations (Figure 4) and the remaining spectral data. The configuration of the Δ5 double bond was assigned as E, as the only NOESY correlation observed from the C-5 proton was to the C-15 protons. No correlations were observed from the C-5 proton to the protons of the 8 or 9 positions. The remaining stereocenters were based on those found in 1. The structure was assigned as 3, and was named glaucolide M. Figure 4 Key HMBC correlations for 3. Compounds 1–3 were found to be cytotoxic in the A2780 human ovarian cancer cell line. Glaucolide M (3, 3.3 μM) was the most active compound, and was slightly more active than glaucolide K (1, 5.8 μM). Glaucolide L (2, 24.5 μM) was the least active.

Sans limiter la reception de l'oeuvre de Cavell a la question du contrat chez Rousseau, l'A. mesure l'influence de Wittgenstein sur la conception de la philosophie comme conversation chez le penseur politique. Substituant la notion d'etat defigure a l'etat aristotelicien, l'A. revise la reception du scepticisme et de la conversation socratique chez Cavell.

We report the case of a professional scuba diver who was unable to dive because he began experiencing severe frontal pain on descent. Following endoscopic surgery to open the frontal recess, the man was able to resume diving unrestricted by pain. We discuss the causes and treatment of this complaint, and we suggest that this might be considered a new indication for surgery in a limited number of cases.

Interrogeant le rapport de la politique actuelle avec la tradition dont elle emerge, l'A. etudie la these de G. Agamben concernant le developpement d'une biopolitique qui detourne les categories aristoteliciennes de son origine. Tandis que s'estompe la distinction entre vie physique et vie politique, l'A. montre que l'analyse d'Agamben ne s'apparente pas a la critique de la technologie chez Heidegger, mais qu'elle rejoint le penseur du Dasein sur la question de l'experience de la souverainete au seuil de la vie et de la mort, du sacre et du sacrifice.

In our continuing search for bioactive molecules from the rainforests of Madagascar as part of an International Cooperative Biodiversity Group (ICBG) program [1], we obtained extracts of Mendoncia cowanii (S. Moore) Benoist roots and stems. M. cowanii is known locally as vahimpianaomby, where it is used against syphilis [2]. These extracts were selected for bioassay-guided fractionation based on their cytotoxic activities in the A2780 human ovarian cancer cell line, with IC50 values of 17 μg/mL for the root extract and 21 μg/mL for the stem extract, and also because no previous chemical studies have been reported for this genus. After solvent partitioning, reversed-phase flash chromatography, and reversed-phased HPLC the crude extract yielded the two new naphthoquinones, avicequinone D and E (1 and 2), and the two known naphthoquinones, avicequinone C (3) and stenocarpoquinone-B (4) [3,4]. Avicequinone D (1) was isolated as a yellow powder. Its UV spectrum, with absorptions at 249 and 295 nm, indicated that it was a naphthoquinone derivative [5]. Its HR-FAB-MS was consistent with a molecular formula of C15H12O5 (m/z 273.0786 [M + H]+). Its 1H-NMR data (Table 1) indicated the presence of two equivalent methyl groups that resonated at δH 1.67 (s), four sp2 methines that resonated at δH 6.81 (s), δH 7.25 (dd, J = 1.2, 8.3 Hz), δH 7.58 (dd, J = 7.5, 8.3 Hz), and δH 7.70 (dd, J = 1.2, 7.5), and one chelated hydroxyl proton that resonated at δH 12.04 (s). The 13C-NMR spectrum (Table 1) contained a methyl resonance of double intensity, an sp3 quaternary carbon resonance at δC 69.5, four sp2 methine resonances, six sp2 quaternary carbon resonances, and two carbonyl resonances. These 1H- and 13C-NMR spectra indicated that 1 was a naphthoquinone. Table 1 1H and 13C NMR data for 1 and 2 (CDCl3) HMBC correlations (Fig. 1) and 1H NMR coupling constants established two fragments. Based on the HMBC experiment the hydroxyl group (δH 12.04) was attached to the carbon that resonated at δC 162.6. Adjacent to it were two sp2 carbons, one was a quaternary carbon that resonated at δC 114.8, and the other was a methine that resonated at δC 125.2 (δH 7.25). Based on coupling constants this methine was clearly one of three methines [δH 7.25 (δC 125.2), δH 7.58 (δC 136.2), and δH 7.70 (δC 120.1)] in an ABC spin system with the methine that resonated at δH 7.58 (dd, J = 7.5, 8.3 Hz) in the B position. The methine that resonated at δH 7.58 (δC 136.2) produced HMBC correlations to the phenolic carbon (δC 162.6) and to an sp2 quaternary carbon (δC 133.3). The third methine of the ABC spin system (δH 7.70/δC 120.1) was found to produce HMBC correlations to the sp2 quaternary carbon that resonated at δC 114.8 as well as the carbonyl carbon that resonated at δC 179.9. The second fragment consisted of a substituted furan ring. The methine that resonated at δH 6.81 (s) (δC 103.0) showed correlations to the sp2 quaternary carbons that resonated at δC 132.1, δC 151.0, and δC 168.6. The methyl resonances (δH 1.67 (s), δC 28.8) were found to show HMBC correlations to the quaternary carbon that resonated at δC 69.5 and the sp2 quaternary carbon that resonated at δC 168.6. Unfortunately, there were no HMBC correlations revealing the orientation of the two fragments to each other, and two structures were therefore possible. HMBC experiments were carried out with the long range JCH set at 5, 8 (the original value), 12, and 15 Hz, in order to determine all relevant correlations, since an HMBC correlation from the H-1′ methine at δH 6.81 (s) (δC 103.0) to one of the carbonyl resonances was vital to the structural determination. In the event, an HMBC correlation from this methine to the carbonyl carbon at δC 179.9 was only observed at the 5 Hz setting, thus providing the connectivity of the two fragments and establishing the structure as 1. In keeping with the nomenclature previously established we propose the trivial name avicequinone D [3]. Fig. 1 HMBC correlations for 1 and 2. Avicequinone E (2) was isolated in low yield as a yellow powder. Its UV spectrum was similar to that of 1, showing that it was also a naphthoquinone derivative. Attempts at obtaining HR-FAB-MS data were not successful, but a weak molecular ion was observed at m/z 275 [M + H]+ in its LR-ESI-MS; this value was consistent with the composition C15H14O5. The composition was supported by resonances in the 1H-NMR spectrum (Table 1) at δH 3.14 (d, 10.1) for the protons of a methylene group and at δH 4.83 (t, 10.1) for the proton of a methine group, as well as resonances for two nonequivalent methyls (δH 1.24 (s) and δH 1.39 (s)). These data indicated that 2 was a dihydrofuran analog of 1. Due to the small amount of compound isolated it was only possible to obtain a partial 13C-NMR spectrum. The structure of 2 was confirmed by hydrogenating a small amount of 1 (1.2 mg) over Pd on carbon in THF at 35 psi [12]. The major product was racemic 2 contaminated with about 35% of the corresponding hydroquinone; pure semisynthetic 2 was obtained by HPLC and had the same retention time as the natural product. The 1H NMR spectrum of semisynthetic 2 was identical to that of the natural product. The HMBC spectrum of semisynthetic 2 (Fig. 1) was in agreement with the partial 13C-NMR spectrum of the natural product, and it also provided all but one of the carbon chemical shifts (Table 1). Compounds 3 and 4 were identified as avicequinone C and stenocarpoquinone-B, respectively, by comparison of their spectroscopic data with literature data [3,4]. Compounds 1-3 were cytotoxic against the A2780 human ovarian cancer cell line with IC50 values of 7.4, 8.8, and 9.8 μM, respectively; compound 4 was much less active with an IC50 value of 50 μM. Compounds 1, 3, and 4 were subsequently found to be weakly active in an Akt kinase inhibition assay with IC50 values of 110, 100, and 70 μM, respectively. Akt has been shown to prevent apoptosis at a postmitochondrial stage through the phosphorylation and inactivation of a number of cellular apoptosis inducers. Glycogen synthase kinase-3, BAD, caspase-9, and several transcription factors such as FKHRL1 have been identified as targets [6-10]. Over expression of Akt has also been implicated in oncogenesis [7], and Akt is thus a promising target in the search for anticancer agents.

Deregulation of signaling pathways is a hallmark of malignant transformation. Signaling-associated phosphoproteins can be degraded to generate cancer-specific phosphopeptides that are presented by major histocompatibility complex (MHC) class I and II molecules and recognized by T cells; however, the contribution of these phosphoprotein-specific T cells to immune surveillance is unclear. We identified 95 phosphopeptides presented on the surface of primary hematological tumors and normal tissues, including 61 that were tumor-specific. Phosphopeptides were more prevalent on more aggressive and malignant samples. CD8(+) T cell lines specific for these phosphopeptides recognized and killed both leukemia cell lines and human leukocyte antigen-matched primary leukemia cells ex vivo. Notably, healthy individuals showed robust CD8(+) T cell responses against many of these phosphopeptides within the circulating memory compartment. This immunity was significantly reduced or absent in some leukemia patients. This reduction correlated with clinical outcome; however, immunity was restored after allogeneic stem cell transplantation. These results suggest that phosphopeptides may be targets of cancer immune surveillance in humans, and point to their importance for development of vaccine-based and T cell adoptive transfer immunotherapies.