Interdisciplinary activities in mathematics and science in the United States

This paper outlines the need for interdisciplinary efforts in mathematics and science at university level in the US. It summarizes the different types of activities currently taking place. They are spread along a spectrum from Minimal coordination to complete integration; each having different advantages and disadvantages. Examples of each type or activity are briefly described.     

Normal strobovideolaryngoscopy: Variability in healthy singers

Strobovideolaryngoscopy has proven essential to accurate diagnosis of voice disorders. Clinical interpretation of stroboscopic images usually follows a standard assessment protocol. Features analyzed typically include symmetry of amplitude, symmetry of phase, regularity of periodicity, amplitudes and wave forms of individual vocal folds, presence or absence of a dynamic segments, and other features. Speed and smoothness of abduction and adduction are also assessed. In order for stroboscopic data to be used meaningfully in a clinical setting, it is essential for the laryngologist to recognize the range of normal variability of these parameters. This may be particularly important when trying to establish diagnoses for subtle voice disorders in professional voice users. This study investigates strobovideolaryngoscopic findings in a population of normal professional singers without voice complaints. “Abnormal” strobovideolaryngoscopic findings occur in this asymptomatic population of “volunteers”. These abnormalities might have been misinterpreted as causing voice complaints if seen for the first time when the singer sought medical care for a voice problem. Physicians must be aware of the range of laryngeal behavior that may be found among normal subjects and must be cautious when interpreting strobovideolaryngoscopic findings. This study also highlights the importance of obtaining “normal” baseline strobovideolaryngoscopic evaluations on professional voice users. The review of strobovideolaryngoscopy performed upon 65 healthy, asymptomatic professional singers revealed an incidence of 58% “abnormal” findings as six clinical entities.     

Two polypropionate metabolites from the cephalaspidean mollusk Philinopsis speciosa

Two polypropionate compounds, niuhinone-A and -B were isolated from a mollusk, $\text{Philinopsis speciosa}$, and their structures were elucidated by spectral methods.     

Activity of Rh-containing catalysts in naphthalene hydrogenation under pressure

Sol-gel method was used for the preparation of titania. A series of sulfated titania catalysts with different sulfate loadings were prepared and characterized by X-ray diffraction, FTIR, UV-VIS DRS, TGA, BET surface area and pore volume. The acidity of these systems was determined by TPD of ammonia. Sulfate ion impregnation decreases the crystallite size and stabilizes the anatase phase of TiO₂. Surface area was found to increase with the sulfate loading. FTIR results show strong bidentate bridge of sulfate species. The catalytic performance of TiO₂/SO₄ ^2- for liquid phase benzylation of toluene was studied. It was found that the conversion increases with sulfate loading. This revised version was published online in August 2006 with corrections to the Cover Date.     

Cationic terminal borylenes by halide abstraction: synthesis and spectroscopic and structural characterization of an Fe=B double bond

The synthesis and the spectroscopic and structural characterization of the cationic terminal borylene complex [Cp*Fe(CO)2(BMes)]+ are reported. Halide abstraction from the corresponding bromoboryl species using Na[BAr f4] generates the borylene as the [BAr f4]- salt in ca. 50% yield. Analyses of IR, NMR, crystallographic, and DFT data are consistent with the presence of an Fe=B double bond.     

Cisplatin carbonato complexes. Implications for uptake, antitumor properties, and toxicity

The reaction of aquated cisplatin with carbonate which is present in culture media and blood is described. The first formed complex is a monochloro monocarbonato species, which upon continued exposure to carbonate slowly forms a biscarbonato complex. The formation of carbonato species under conditions that simulate therapy may have important implications for uptake, antitumor properties, and toxicity of cisplatin.     

The crystal structure of RbHSeO4: A neutron diffraction study of the paraelectric phase

The structure of the paraelectric phase of RbHSeO₄ has been determined at 387 K by neutron diffraction. The structure consists of chains of hydrogen bonded SeO₄ groups extending along the crystallographic b axis. Two different hydrogen bonds have been characterized, with OO distances of 2.524(4) and 2.583(3) Å. In the shorter OHO hydrogen bond the hydrogen atom is disordered, suggesting that the ordering of hydrogen participates directly in the phase transition to the ferroelectric phase.     

Use of ProteinChip array surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) to identify thymosin beta-4, a differentially secreted protein from lymphoblastoid cell lines

The identification of proteins differentially expressed between cancer and normal cells is vital for the development of cancer diagnostics, therapeutics and vaccines. Using a ProteinChip Biomarker System (Ciphergen Biosystems, Fremont, CA) which combines ProteinChip technology with time-of-flight mass spectrometry, we have developed a simple method to screen and identify differentially secreted proteins from tumor cell lines. Mass spectra of the range of proteins secreted from normal B-cells were generated along with those secreted from Epstein-Barr virus transformed B-cells. A mass peak at m/z = 4972.1 that was highly over-represented in the transformed B-cell line was chosen for identification and purified by reversed phase chromatography with concomitant monitoring of fractions by SELDI-TOF MS. The resulting purified protein was digested with trypsin and the peptide masses derived from the SELDI-TOF spectrum were used to search the public databases for protein identification. Fragment matching of the resulting peptides identified the protein as thymosin beta-4. Using LC-electrospray ionization MS/MS, the identity of this protein was confirmed. Thymosin beta-4 is a known marker in LCLs establishing the utility of this method to discover and identify proteins differentially expressed between cancers and their matched normal counterparts.     

Carbonyl analogues? Analysis of Fe-E (E=B, Al, Ga) bonding in cationic terminal diyl complexes by density functional theory

A series of DFT calculations has been carried out with the aim of characterizing the metal-group 13 element interaction in the novel cationic borylene complex [(eta5-C2Me5)Fe(CO)2(BMes)]+ (1) and related species of the type [eta5-C5R5)M(L)2(EX)]n+. In addition, comparisons have been made with charge neutral borylene complexes and with related group 14 based ligand systems (e.g. cationic metal carbonyls, carbenes and vinylidenes) for which models of bonding have previously been established. In this regard particular attention has been focused on the interpretation of (i) molecular orbital composition; (ii) bond dissociation energies (BDEs) and the ratio of ionic to covalent contributions (DeltaEelstat/DeltaEorb); and (iii) sigma and pi symmetry covalent contributions. The molecular orbital compositions for the prototype borylene complex 1 and for related cationic and neutral systems [e.g.[(eta5-C5H5)Fe(PMe3)2(BMes)]+ and (eta5-C5H5)Mn(CO2(BMes)]] are consistent with the presence of bonding interactions between metal and borylene fragments of both sigma and pi symmetry. Furthermore, on the basis of BDEs, DeltaEorb values and sigma/pi covalent ratios, the bonding in cationic terminal borylene complexes such as 1 appears to have as much right to be termed a M=E double bond as does that in archetypal Fischer carbene and related complexes such as [(eta5-C5R5)Fe(CO)2(CCMe2)]+ and [(eta5-C5R5)Fe(CO)2(CH2)]+.