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We report the identification and quantitative isolation of Au145(SR)60X (R = n-butyl, n-pentyl; X = halide) along with elucidation of key properties as compared to the corresponding ubiquitous chiral-icosahedral Au144(SR)60 cluster known to have a central vacancy. The stoichiometries were assessed by electrospray mass spectrometry (ESI-MS) at isotopic resolution, and induced dissociation patterns indicate the ‘extra’ (Au,Br) atoms are strongly bound components of these structures. Voltammetric and spectroscopic characterization reveals Au145(SR)60X behaviors that are qualitatively similar to yet fascinatingly distinct from those of Au144(SR)60. (1H,13C)-NMR spectra clearly show how both Au145(SR)60X and Au144(SR)60 are capped by 12 distinct ligand types of 5-fold equivalence, as was recently established for Au144(SR)60 capped by shorter ligands, demonstrating that this novel cluster shares the same chiral-icosahedral motif. Intriguingly, Au145(SR)60X is strongly near-IR luminescent, whereas under comparable conditions Au144(SR)60 barely emits. The photoluminescence pattern of Au145(SR)60X is very similar to that observed for Au25(SR)18, which contains the Au13 core. The combined results are interpreted as consistent with neutral Au145(SR)60X as a diamagnetic species, electronically and structurally similar to the corresponding Au144(SR)60 compounds.

This paper attempts to understand further the working of values in ethics and religion. Its premise is that the psyche is organized by its internal objects, and that understanding the effective working of values therefore requires understanding the relevant internal objects. It begins with a brief outline of the history of internal objects in the thought of Freud, Klein, Fairbairn, Winnicott and Loewald, and suggests that they are best thought of as "phenomenological" in nature, meaning that, whether conscious or unconscious, they appear in the mind without an enduring substrate. Using the thought of Loewald and of the philosopher Emmanuel Levinas in particular, it suggests that the functioning of "allegory" offers an important avenue to understanding how certain internal objects act to organize the psyche hierarchically on a basis of values including ethical ones. "Religious objects" may then be understood as a subclass of "allegorical objects", acting analogously to Levinas's "face of the other" and experienced as giving access to "transcendent" (commanding) values. Such values are not adequately described by traditional accounts of a superego and require a deepening of the psychoanalytic dialogue with philosophy.

Many antibiotic resistances to penicillin have been reported, making them obsolete against multiresistant bacteria. Because penicillins act by inhibiting cell wall production while silver particles...

We report the identification and quantitative isolation of Au

Monolayer-protected clusters (MPCs), typified by the (Au, Ag)-thiolates, share dimensions and masses with aqueous globular proteins (enzymes), yet efficient bioanalytical methods have not proved applicable to MPC analytics. Here we demonstrate that direct facile ESI(+)MS analysis of MPCs succeeds, at the few-picomol level, for aqueous basic amino-terminated thiolates. Specifically, captamino-gold clusters, Au n(SR) p, wherein -R = -(CH2)2N(CH3)2, are prepared quantitatively via a direct one-phase (aq/EtOH) method and are sprayed under weakly acidic conditions to yield intact 6.8 kDa complexes, ( n, p) = (25, 18), with up to 5 H+ adducts, or 34.6 kDa MPCs (144, 60) at charge state z = 8+. These exceed all prior reports of positive charging of MPCs except for those bearing per-cationized (quat) ligands. pH-mediated reversible phase transfer (aqueous to/from DCM-rich phases) are consistent with peripheral exposure of all tertiary amino groups to solutions. This surprising development opens the way to all manner of modifications or extensions, as well as to advanced analyses inspired by those applied to intact biomolecules.

A nonaqueous reversed phase liquid chromatography-mass spectrometry (LC-MS) method has been developed for extremely hydrophobic MPCs (monolayer-protected clusters), and has been applied to the efficient separation of gold–dodecanethiolate (ddt) assemblies, leading to the identification of three dodecanethiolate-protected gold clusters, Au130(ddt)50, Au137(ddt)56, and Au144(ddt)60, as prominent components of a commercial product of nominally 2 nm (core-diameter) protected gold nanoparticles obtained from nanoComposix, Inc. Various components were separated, according to hydrophobic character, using a linear gradient of methanol–dichloromethane mobile phases, on a C18 HPLC column. Varying concentrations of mobile-phase modifier (triethylammonium acetate) were compared for effect on chromatographic peak shape and cluster retention. Positive electrospray ionization (ESI) was used to ionize all components in the sample. LC separation prior to inline + ESI-MS detection facilitated sample analysis via production...

Evidence for the existence of condensed-phase isomers of silver-lipoate clusters, Ag29(LA)12, where LA = (R)-α lipoic acid, was obtained by reversed-phase ion-pair liquid chromatography with in-line UV–vis and electrospray ionization (ESI)-MS detection. All components of a raw mixture were separated according to surface chemistry and increasing size via reversed-phase gradient HPLC methods and identified by their corresponding m/z ratio by ESI in the negative ionization mode. Aqueous and methanol mobile-phase mixtures, each containing 400 mM hexafluoroisopropanol (HFIP)–15 mM triethylamine (TEA), were employed to facilitate the interaction between the clusters and stationary phase via formation of ion-pairs. TEA-HFIP (triethylammonium-hexafluoroisopropoxide) had been shown to provide superior chromatographic peak shape and mass spectral signal compared with alternative modifiers such as TEAA (triethylammonium-acetate) for analysis of oligonucleotide samples. Liquid chromatographic separation prior to mass...

El poder de la Divina Comedia de Dante es indudable, pero sorprendente en vista de que su estructura y sus supuestos teologicos ya no estan vigentes entre la mayoria de los lectores modernos. Este ...

We report the first results of ultraviolet photodissociation (UVPD) mass spectrometry of trapped monolayer-protected cluster (MPC) ions generated by electrospray ionization. Gold clusters Au25(pMBA)18 and Au36(pMBA)24 (pMBA = para-mercaptobenzoic acid) were analyzed in both the positive and negative modes. Whereas activation methods including collisional- and electron-based methods produced relatively few fragment ions, even a single ultraviolet pulse (at λ = 193 nm) caused extensive fragmentation of the positively charged clusters. Upon photoactivation using a low number of laser pulses, the staple motifs of both clusters were cleaved and stripped of the protecting ligand portions without removal of any contained gold atoms. This striking process involved Au–S and C–S bond cleavages via a pathway made possible by 6.4 eV photon absorption. Monomer evaporation (neutral gold atom loss) occurred upon exposure to multiple pulses, resulting in a size series of bare gold-cluster ions. All tandem mass spectromet...

A partir de un esbozo de la historia del budismo desde una perspectiva psicoanalitica, este trabajo utiliza ideas de la filosofia y el psicoanalisis para examinar la naturaleza de la eficacia psico...

Herein we disclose methods that greatly improve the solution- and gas-phase handling properties of larger aqueous-phase gold–thiolate clusters, which previously presented extreme technical obstacles to molecular analysis and size control, even as they have enjoyed ever-wider applications in materials science and biomedicine. The methods are based upon an analogy between the polyacidic surface structure of the pMBA-protected clusters (pMBA = p-mercaptobenzoic acid) and that of oligonucleotides. A volatile ion-pairing reagent, TEA = triethylamine, greatly improves solution-phase stability near neutral pH and thus facilitates both electrospray generation of the gas-phase ions and the in-line reversed-phase ion-pairing HPLC-ESI-MS approach to analyzing complex mixtures of Au-pMBA oligomers and clusters. Previously anticipated but never established compounds, including Au36(pMBA)24, are thereby demonstrated. These results are in accord with recent theoretical simulations of ion pairing of model Au144(pMBA)60 c...

Gold clusters protected by 3-MBA ligands (MBA = mercaptobenzoic acid, &ndash, SPhCO2H) have attracted recent interest due to their unusual structures and their advantageous ligand-exchange and bioconjugation properties. Azubel et al. first determined the core structure of an Au68-complex, which was estimated to have 32 ligands (3-MBA groups). To explain the exceptional structure-composition and reaction properties of this complex, and its larger homologs, Tero et al. proposed a &ldquo, dynamic stabilization&rdquo, via carboxyl O&ndash, H&ndash, &ndash, Au interactions. Herein, we report the first results of an integrated liquid chromatography/mass spectrometer (LC/MS) analysis of unfractionated samples of gold/3-MBA clusters, spanning a narrow size range 13.4 to 18.1 kDa. Using high-throughput procedures adapted from bio-macromolecule analyses, we show that integrated capillary high performance liquid chromatography electrospray ionization mass spectrometer (HPLC-ESI-MS), based on aqueous-methanol mobile phases and ion-pairing reverse-phase chromatography, can separate several major components from the nanoclusters mixture that may be difficult to resolve by standard native gel electrophoresis due to their similar size and charge. For each component, one obtains a well-resolved mass spectrum, nearly free of adducts or signs of fragmentation. A consistent set of molecular mass determinations is calculated from detected charge-states tunable from 3&minus, (or lower), to 2+ (or higher). One thus arrives at a series of new compositions (n, p) specific to the Au/3-MBA system. The smallest major component is assigned to the previously unknown (48, 26), the largest one is evidently (67, 30), vs. the anticipated (68, 32). Various explanations for this discrepancy are considered. A prospective is given for the various members of this novel series, along with a summary of the advantages and present limitations of the micro-scale integrated LC/MS approach in characterizing such metallic-core macro-molecules, and their derivatives.

Monolayer-protected clusters (MPCs), typified by the (Au, Ag)-thiolates, share dimensions and masses with aqueous globular proteins (enzymes), yet efficient bioanalytical methods have not proved applicable to MPC analytics. Here we demonstrate that direct facile ESI(+)MS analysis of MPCs succeeds, at the few-picomol level, for aqueous basic amino-terminated thiolates. Specifically, captamino-gold clusters, Au

Recent advances in cluster synthesis make it possible to produce an enormous variety molecule-like MPCs of size, composition, shape, and surface-chemical combinations. In contrast to the significant growth in the synthetic capability to generate these materials, progress in establishing the physicochemical basis for their observed properties has remained limited. The main reason for this has been the lack of the analytical capability to generate and measure samples of suitably high (molecular) purity; such capability is also essential to support therapeutic and diagnostic MPC development. In order for MPC products to get to market, especially those products that are medical-field related, characterization is required to identify and quantify all components present in a material mixture. Here, we show results from analysis of several synthetic mixtures of gold MPCs by nonaqueous reversed-phase chromatography coupled with mass spectrometry detection. The additional or hidden components, revealed to be present in these mixtures, provide novel insights into their comparative stability and interactions.

Experimental and theoretical evidence reveals the resilience and stability of the larger aqueous gold clusters protected with p-mercaptobenzoic acid ligands (pMBA) of composition Aun(pMBA)p or (n, p). The Au144(pMBA)60, (144, 60), or gold-144 aqueous gold cluster is considered special because of its high symmetry, abundance, and icosahedral structure as well as its many potential uses in material and biological sciences. Yet, to this date, direct confirmation of its precise composition and total structure remains elusive. Results presented here from characterization via high-resolution electrospray ionization mass spectrometry on an Orbitrap instrument confirm Au102(pMBA)44 at isotopic resolution. Further, what usually appears as a single band for (144, 60) in electrophoresis (PAGE) is shown to also contain the (130, 50), recently determined to have a truncated-decahedral structure, and a (137, 56) component in addition to the dominant (144, 60) compound of chiral-icosahedral structure. This finding is significant in that it reveals the existence of structures never before observed in all-aromatic water-soluble species while pointing out the path toward elucidation of the thermodynamic control of protected gold nanocrystal formation.

Gold nanoclusters (AuNCs) with well-defined structure and arrangement possess particular physical and functional properties. AuNCs that differ only by less than 1 nm in diameter corresponding to one atomic layer show different structural, optical, and physicochemical properties in a size-dependent mode, making their analytical characterization a challenge. Herein we describe an integrative approach to characterization of larger aqueous AuNC (Au102-pMBA44, Au144pMBA60 and higher) selected by gel electrophoresis (PAGE). We employ UV–vis, dynamic light scattering, and zeta-potential in combination with high-performance analytical techniques such as multiwavelength analytical ultracentrifugation and electrospray ionization mass spectrometry were used to separate aqueous AuNCs and to determine their specific hydrodynamic diameter, partial abundance, molecular weight, and mass/charge ratios when present in a complex mixture of AuNCs containing Au102 (1.6 nm), Au144 (2 nm), and Au288–328 (2.5 nm). Advanced analy...

The properties of atomically monodisperse noble metal nanoclusters (NCs) are intricately intertwined with their precise molecular formula. The vast majority of size-specific NC syntheses start from the reduction of the metal salt and thiol ligand mixture. Only in gold was it recently shown that ligand-exchange could induce the growth of NCs from one atomically precise species to another, a process of yet unknown reversibility. Here, we present a process for the ligand-exchange-induced growth of atomically precise silver NCs, in a biphasic liquid-liquid system, which is particularly of interest because of its complete reversibility and ability to occur at room temperature. We explore this phenomenon in-depth using Ag35(SG)18 [SG = glutathionate] and Ag44(4-FTP)30 [4-FTP = 4-fluorothiophenol] as model systems. We show that the ligand-exchange conversion of Ag35(SG)18 into Ag44(4-FTP)30 is rapid (

For two decades, Au144(SR)60 has been one of the most studied and used thiolate (SR) protected gold nanoclusters. In many ways, however, it proved to be a challenging and elusive case, also because of the difficulties in solving its structure by single-crystal X-ray crystallography. We used very short thiols and could prepare Au144(SC2H5)60 and Au144(SC3H7)60 in a very pure form, which was confirmed by UV-vis absorption spectroscopy and very regular electrochemistry patterns. Inductively coupled plasma and electrospray ionization mass spectrometries gave definite proof of the Au144(SR)60 stoichiometry. High-resolution 1D and 2D NMR spectroscopy in the solution phase provided the result of assessing the presence of 12 ligand types in exactly the same amount (5-fold equivalence). Equally important, we found that the two protons belonging to each methylene group along the thiolate chain are diastereotopic. For the α-CH2 protons, the diastereotopic effect can be indeed gigantic, as it reaches chemical-shift differences of 2.9 ppm. DFT calculations provided insights into the relationship between structure and NMR results. In particular, the 12 ligand types and corresponding diastereotopic effects may be explained by considering the presence of C-H···S hydrogen bonds. These results thus provide fundamental insights into the structure of the thiolate layer capping this long-studied gold nanocluster.

Evidence for the existence of condensed-phase isomers of silver-lipoate clusters, Ag

International audience; Solving the atomic structure of metallic clusters is fundamental to understanding their optical, electronic, and chemical properties. Herein we present the structure of the largest aqueous gold cluster, Au 146 (p-MBA) 57 (p-MBA: para-mercaptobenzoic acid), solved by electron diffraction (MicroED) to subatomic resolution (0.85 Å) and by X-ray diffraction at atomic resolution (1.3 Å). The 146 gold atoms may be decomposed into two constituent sets consisting of 119 core and 27 peripheral atoms. The core atoms are organized in a twinned FCC structure whereas the surface gold atoms follow a C 2 rotational symmetry about an axis bisecting the twinning plane. The protective layer of 57 p-MBAs fully encloses the cluster and comprises bridging, monomeric, and dimeric staple motifs. Au 146 (p-MBA) 57 is the largest cluster observed exhibiting a bulk-like FCC structure as well as the smallest gold particle exhibiting a stacking fault.

Solving the atomic structure of metallic clusters is fundamental to understanding their optical, electronic, and chemical properties. Herein we present the structure of the largest aqueous gold cluster, Au146(p-MBA)57 (p-MBA: para-mercaptobenzoic acid), solved by electron diffraction (MicroED) to subatomic resolution (0.85 Å) and by X-ray diffraction at atomic resolution (1.3 Å). The 146 gold atoms may be decomposed into two constituent sets consisting of 119 core and 27 peripheral atoms. The core atoms are organized in a twinned FCC structure whereas the surface gold atoms follow a C2 rotational symmetry about an axis bisecting the twinning plane. The protective layer of 57 p-MBAs fully encloses the cluster and comprises bridging, monomeric, and dimeric staple motifs. Au146(p-MBA)57 is the largest cluster observed exhibiting a bulk-like FCC structure as well as the smallest gold particle exhibiting a stacking fault.

This paper starts from the thought that we cannot take for granted that a society's highest values will survive in the long term as effective motivators within that society. By ‘highest values’ I mean values such as justice, concern for members of weak and minority groups, and respect for promises and for the attempt to speak truthfully – values that apply at the highest level of generality. If they are to survive and to be effective, two things may be necessary: firstly, unpredictable ‘epiphanic’ moments in which the power of these values is emotionally experienced by individuals, and secondly, institutions and a vocabulary in which these values can be remembered, discussed and affirmed in emotionally and imaginatively impactful ways. I shall suggest, with reference in particular to the thought of Emmanuel Levinas and Ronald Dworkin, that the second of these factors, the remembering and affirmation of values, marks out the crucial, perhaps even the irreplaceable, contribution of a ‘religion’ to a society. The failure, within psychoanalysis and also more widely, to appreciate the working of this function in a society over generations may mean that the consequences of ‘growing out of religion’ (Winnicott) have not yet been adequately recognized.

The protected noble-metal structures comprising 145 metal-atom sites and 60 ligands are among the frequently identified larger metal-cluster systems exploited in many avenues of research. Herein we report a comparative electrospray ionization-mass spectrometry (ESI-MS) investigation of the 60-fold thiolated Au144 and CuAu144 clusters, in various positive charge-states, in conjunction with a density-functional theoretical (DFT) analysis based upon the icosahedral Pd145-structure-type applicable to these systems. Samples rich in the hexanethiolate-protected CuAu144 clusters are obtained via a single-phase reduction process. The predicted electronic structure of the vacancy-centered Au144(SR)60 system provided a simple rationale for the limiting [4+] charge-state observed of Au144, whereas the maximal [3+] charge detected on the CuAu144(SR)60 cluster can be explained if the 145th atom occupies the central site. Occupancy of the center-site stabilizes the superatomic 3S-orbital, and thereby shifts the shell-c...

Gas-phase reactions of larger gold clusters are poorly known because generation of the intact parent species for mass spectrometric analysis remains quite challenging. Herein we report in-source collision-induced dissociation (CID) results for the monolayer protected clusters (MPCs) Au144(SR)60 and Au130(SR)50, where R- = PhCH2CH2-, in a Bruker micrOTOF time-of-flight mass spectrometer. A sample mixture of the two clusters was introduced into the mass spectrometer by positive mode electrospray ionization. Standard source conditions were used to acquire a reference mass spectrum, exhibiting negligible fragmentation, and then the capillary-skimmer potential difference was increased to induce in-source CID within this low-pressure region (~4 mbar). Remarkably, distinctive fragmentation patterns are observed for each MPC[3+] parent ion. An assignment of all the major dissociation products (ions and neutrals) is deduced and interpreted by using the distinguishing characteristics in the standard structure-models for the respective MPCs. Also, we propose a ring-forming elimination mechanism to explain R-H neutral loss, as separate from the channels leading to RS-SR or (AuSR)4 neutrals.

We report the first results of ultraviolet photodissociation (UVPD) mass spectrometry of trapped monolayer-protected cluster (MPC) ions generated by electrospray ionization. Gold clusters Au

The power of Dante's Divine Comedy is unmistakable, but surprising in view of its theological structure and assumptions that are no longer current among most modern readers. This paper suggests that its power derives from the deep psychological truthfulness with which Dante deals with the painful personal crisis that underlies the poem and is his starting point. It attempts to clarify what may have constituted that crisis, and why the structure of the Comedy, and in particular its use of two guides, Virgil and Beatrice, who might be thought a somewhat incompatible pairing, point significantly to the nature of the solution Dante arrived at. In particular it suggests that the puzzling fictions to do with Statius in the Purgatorio are a clue to Dante's own difficulties in bridging the classical and Christian traditions, and that his highly original solution to these difficulties, by no means conforming to conventional Christian orthodoxy in the 13th/14th century, was needed with special urgency in a time of pervasive civil conflict.

Calcium channel blocker poisonings are the leading cause of death from cardiovascular medication-related overdoses (Mowry et al. Clin Toxicol (Phila) 52(10):1032–1283, 2014; Shenoy et al. J Hosp Med 9(10):663–668, 2014). Clinical effects in the poisoned patient may include hypotension, bradycardia, atrioventricular conduction disturbances, pulmonary edema, stroke, bowel ischemia, altered mental status, and cardiac arrest. Many immediate and sustained-release preparations exist, hence pharmacokinetics are highly variable. Calcium channel blockers are generally lipophilic and highly-protein bound, rendering traditional extracorporeal elimination methods such as hemodialysis largely ineffective.

Translations of summary Starting with an outline of Buddhist history from a psychoanalytic perspective, this paper uses ideas from philosophy and psychoanalysis to consider the nature of the psychological effectiveness of religious objects. It suggests that the development of the devotional cult of Buddhas ‘without form’ such as Amitābha, at-first-glance surprising when juxtaposed with the founding vision of Gautama Siddhartha, tells us a great deal about the psychological needs that impel the evolution of religious thinking. Distinguishing religious objects from mythological ones, it argues that ‘religious objects’ are, more specifically, allegorical objects that can be encountered in the second person; that these may not always be well described as ‘illusion’; and that they may in some cases be better understood as providing opportunities for experience that, like the transference in psychoanalysis, may have far-reaching psychological impacts.

In this study, the feasibility of Integra acellular collagen used as a vascular carrier in skin flap prefabrication was examined. In all, 20 Sprague--Dawley rats were randomly divided into 3 groups. The saphenous vascular bundle was used as the vascular carrier. In group 1 (n = 8), an arteriovenous fistula was made by anastomosis of distal saphenous artery and vein. An Integra patch (2 × 3 cm²) was placed underneath the vascular bundle. In group 2 (n = 6), an Integra patch was placed on the top of the saphenous vessels, which remained intact. In group 3 (n = 6), an arteriovenous fistula was made without Integra implant. Two weeks after the initial management, a skin flap (2 × 3 cm² in size) was raised and replaced in each group. The survival of the flaps and histology were evaluated at 7 days after flap replacement. The results showed that the average survival area in group 1 was 98% ± 2%. No flap survival was observed in group 2. The mean survival area in group 3 was 29% ± 6%. The differences among all 3 groups were significant (P < 0.05). Although the mean survival area in group 3 was significantly lower than that in group 1 (P < 0.001), it was significantly higher than that in group 2. Histology showed that the Integra patch was incorporated into the adjacent connective tissue, and increased amounts of neovascularization were seen between the collagenous sheets and dermis in group 1. In conclusion, this study demonstrated that Integra acellular collagen can incorporate into the adjacent tissue as a vascular carrier and induce angiogenesis in flap prefabrication. This biomaterial can provide a scaffold for supporting and enhancing the survival of a vascular prefabricated skin flap. The results indicate that this material is an ideal biomaterial for flap prefabrication and may be used for this clinical purpose in the future.

Summary ‘No vertical scar' techniques of breast shaping have received increasing attention during the last decade and are sometimes viewed as ‘new' methods. In this article, we provide a comprehensive introduction to the roots of this procedure. Raymond Passot has to be credited with the original design of ‘no vertical scar' methods. We provide a contemporary translation of his original article written in French in 1925. The historical context of this new procedure was researched using original sources that were in French and German languages. The evolution of the procedure and its reception by Passot's contemporaries up to 1932 are examined, which give insight into the concepts of blood supply to the breast, shaping techniques and the aetiopathology of breast deformities in the pre-World War II era, which were successfully developed by the Austrian–German school of thought, resulting in the birth of modern breast shaping surgery based on Passot's ‘no vertical scar' procedure. The lasting truths discovered in that era were frequently reinvented in the subsequent decades in English without crediting the original authors.

An efficient highly diastereo- and enantioselective synthesis of the bis-tetrahydrofuran (bis-THF) alcohol of several HIV protease inhibitors, including Brecanavir and Darunavir, has been achieved utilizing an Evans Mukaiyama aldol reaction of (benzyloxy)acetaldehyde and a silyl ketene acetal. The lactone alcohol intermediate from the catalytic aldol reaction was reduced to a lactol. Palladium catalyzed hydrogenolysis removed the benzyl protection and promoted an in situ cyclization to form the epimer of the bis-THF alcohol in a 98:2 diastereomeric ratio and 97:3 enantiomeric ratio. The alcohol epimer was readily converted to the target in two steps by oxidation to a ketone followed by highly selective reduction to the bis-THF alcohol.