Reactivity and infrared spectroscopy of gaseous hydrated trivalent metal ions.

Hydrated trivalent rare earth metal ions containing yttrium and all naturally abundant lanthanide metals are formed using electrospray ionization, and the structures and reactivities of these ions containing 17-21 water molecules are probed using blackbody infrared radiative dissociation (BIRD) and infrared action spectroscopy. With the low-energy activation conditions of BIRD, there is an abrupt transition in the dissociation pathway from the exclusive loss of a single neutral water molecule to the exclusive loss of a small protonated water cluster via a charge-separation process. This transition occurs over a narrow range of cluster sizes that differs by only a few water molecules for each metal ion.

A Holocene pollen record of savanna establishment in coastal Amapá.

The main goal of this study was to investigate how climate and human activities may have influenced ecotonal areas of disjoint savannas within Brazilian Amazonia. The fossil pollen and charcoal records of Lake Márcio (Amapá) were used to provide a Holocene palaeoecological history of this region. Detrended correspondence analysis (DCA) was used to enhance the patterns of sample distribution along the sediment core.

Patch testing a patient with allergic contact hand dermatitis who is taking infliximab.

We report the case of a patient who developed allergic contact hand dermatitis while receiving infliximab infusions for psoriasis and psoriatic arthritis. Patch testing showed multiple positive allergens. To our knowledge, this is the first case report of successful patch testing in a patient receiving tumor necrosis factor-alpha (TNF-alpha) blockade therapy.

Effects of alkaline earth metal ion complexation on amino acid zwitterion stability: results from infrared action spectroscopy.

The structures of isolated alkaline earth metal cationized amino acids are investigated using infrared multiple photon dissociation (IRMPD) spectroscopy and theory. These results indicate that arginine, glutamine, proline, serine, and valine all adopt zwitterionic structures when complexed with divalent barium. The IRMPD spectra for these ions exhibit bands assigned to carboxylate stretching modes, spectral signatures for zwitterionic amino acids, and lack bands attributable to the carbonyl stretch of a carboxylic acid functional group.

Ultraviolet illumination as an adjunctive aid in dental inspection.

Tooth-colored resin fillings have become increasingly popular as restorative materials. Their presence in the dentition presents a challenge to the clinician and the forensic odontologist, as detection of the fillings can be difficult both visually and radiographically. As they necessarily form part of the unique dentition of an individual, recognition of the resins is important for forensic identification.

Long-term hearing results in gamma knife radiosurgery for acoustic neuromas.

Objectives: There are many studies that have examined functional outcomes following Gamma Knife treatment; however, few have reported long-term audiometric data. This study analyzed the long-term hearing results of Gamma Knife radiosurgery in the treatment of acoustic neuromas.

Study Design: Retrospective cohort study.

Vegetation and hydrology changes in Eastern Amazonia inferred from a pollen record.

Pollen, charcoal, and C14 analyses were performed on a sediment core obtained from Lake Tapera (Amapá) to provide the palaeoenvironmental history of this part of Amazonia. A multivariate analysis technique, Detrended Correspondence Analysis, was applied to the pollen data to improve visualization of sample distribution and similarity. A sedimentary hiatus lasting 5,500 years was identified in the Lake Tapera.

Identification of incinerated root canal filling materials after exposure to high heat incineration.

With the increase in global terrorism there is a higher probability of having to identify victims of incineration events secondary to incendiary explosive devices. The victims of incineration events challenge forensic odontologists when coronal restorations are no longer present to compile postmortem data. With 40 million root canals being completed annually in the United States, a very large pool of antemortem data is available to the forensic odontologist to make positive identifications.

Analytical survey of restorative resins by SEM/EDS and XRF: databases for forensic purposes.

Frequently in forensic cases, unknown substances must be identified. Automated databases can ease the burden of comparison as materials may be compared against many known standards in a relatively short period of time. It has been shown that dental resins can be named according to brand or brand group even in conditions as harsh as cremation.

Absolute standard hydrogen electrode potential measured by reduction of aqueous nanodrops in the gas phase.

In solution, half-cell potentials are measured relative to those of other half cells, thereby establishing a ladder of thermochemical values that are referenced to the standard hydrogen electrode (SHE), which is arbitrarily assigned a value of exactly 0 V. Although there has been considerable interest in, and efforts toward, establishing an absolute electrochemical half-cell potential in solution, there is no general consensus regarding the best approach to obtain this value. Here, ion-electron recombination energies resulting from electron capture by gas-phase nanodrops containing individual [M(NH3)6]3+, M = Ru, Co, Os, Cr, and Ir, and Cu2+ ions are obtained from the number of water molecules that are lost from the reduced precursors.

Fire, climate change and biodiversity in Amazonia: a Late-Holocene perspective.

Fire is an important and arguably unnatural component of many wet Amazonian and Andean forest systems. Soil charcoal has been used to infer widespread human use of landscapes prior to European Conquest. An analysis of Amazonian soil carbon records reveals that the records have distinct spatial and temporal patterns, suggesting that either fires were only set in moderately seasonal areas of Amazonia or that strongly seasonal and aseasonal areas are undersampled.

A cyclin-dependent protein kinase, CDKC2, colocalizes with and modulates the distribution of spliceosomal components in Arabidopsis.

Cyclin-dependent kinases (CDKs) play key regulatory roles in diverse cellular functions, including cell-cycle progression, transcription and translation. In plants, CDKs have been classified into several groups, named A through to G, but the functions of most are poorly characterized. CDKCs are known to phosphorylate the C-terminal domain (CTD) of RNA polymerase II (RNAP II), and therefore the CDKC-cyclinT (CycT) complex may have a role similar to the animal CDK9-CycT complex of the positive transcription elongation factor b (P-TEFb).

Nanomilled oral testosterone plus dutasteride effectively normalizes serum testosterone in normal men with induced hypogonadism.

Oral androgen development has been hampered by the rapid metabolism of orally administered testosterone (T) and low bioavailibility. The addition of the 5alpha-reductase inhibitor dutasteride (D) to oral T in oil dramatically improves concentrations of serum T. In this study we evaluate the absorption of oral T+D, comparing nanomilled T (NmT+D) vs T dissolved in oil (Capmul; CpT+D), as nanomilling might offer a simpler, more practical means of oral T administration, given the limited solubility of T in oil.

Control of protein translation by phosphorylation of the mRNA 5'-cap-binding complex.

Initiation of mRNA translation is a key regulatory step in the control of gene expression. Microarray analysis indicates that total mRNA levels do not always reflect protein levels, since mRNA association with polyribosomes is necessary for protein synthesis. Phosphorylation of translation initiation factors offers a cost-effective and rapid way to adapt to physiological and environmental changes, and there is increasing evidence that many of these factors are subject to multiple regulatory phosphorylation events.

Infrared spectroscopy of arginine cation complexes: direct observation of gas-phase zwitterions.

The structures of cationized arginine complexes [Arg + M]+, (M = H, Li, Na, K, Rb, Cs, and Ag) and protonated arginine methyl ester [ArgOMe + H]+ have been investigated in the gas phase using calculations and infrared multiple-photon dissociation spectroscopy between 800 and 1900 cm-1 in a Fourier transform ion cyclotron resonance mass spectrometer. The structure of arginine in these complexes depends on the identity of the cation, adopting either a zwitterionic form (in salt-bridge complexes) or a non-zwitterionic form (in charge-solvated complexes). A diagnostic band above 1700 cm-1, assigned to the carbonyl stretch, is observed for [ArgOMe + H]+ and [Arg + M]+, (M = H, Li, and Ag), clearly indicating that Arg in these complexes is non-zwitterionic.

Reference cardiopulmonary physiologic parameters for standing, unrestrained white rhinoceroses (Ceratotherium simum).

Chemical restraint is an important tool for the management and medical care of both captive and free-ranging rhinoceroses. Current anesthetic protocols for the white rhinoceros (Ceratotherium simum) are reported to cause varying degrees of hypertension, tachycardia, muscular stiffness and fasciculation, acidosis, and, most importantly, respiratory depression with resulting hypoventilation, hypoxia, and hypercapnea. To assist in the assessment and development of new and improved anesthetic techniques for the white rhinoceros, the following cardiopulmonary reference parameters for standing, unrestrained white rhinoceroses were generated (mean +/- standard error [minimum maximum]): heart rate = 39 +/- 0.

Intensive diabetes therapy and body weight: focus on insulin detemir.

Weight gain can be a significant barrier to the treatment of diabetes. Insulin detemir is a basal insulin analog that can help patients move safely toward glycemic targets with less weight gain. This review discusses the potential adverse effects of, and hypothesis for, weight gain resulting from intensive insulin management of diabetes.

One water molecule stabilizes the cationized arginine zwitterion.

Singly hydrated clusters of lithiated arginine, sodiated arginine, and lithiated arginine methyl ester are investigated using infrared action spectroscopy and computational chemistry. Whereas unsolvated lithiated arginine is nonzwitterionic, these results provide compelling evidence that attachment of a single water molecule to this ion makes the zwitterionic form of arginine, in which the side chain is protonated, more stable. The experimental spectra of lithiated and sodiated arginine with one water molecule are very similar and contain spectral signatures for protonated side chains, whereas those of lithiated arginine and singly hydrated lithiated arginine methyl ester are different and contain spectral signatures for neutral side chains.

Arabidopsis POT1A interacts with TERT-V(I8), an N-terminal splicing variant of telomerase.

Chromosome integrity is maintained via the actions of ribonucleoprotein complexes that can add telomeric repeats or can protect the chromosome end from being degraded. POT1 (protection of telomeres 1), a class of single-stranded-DNA-binding proteins, is a regulator of telomeric length. The Arabidopsis genome contains three POT1 homologues: POT1A, POT1B and POT1C.

Hydration of the calcium dication: direct evidence for second shell formation from infrared spectroscopy.

Infrared laser action spectroscopy in a Fourier-transform ion cyclotron resonance mass spectrometer is used in conjunction with ab initio calculations to investigate doubly charged, hydrated clusters of calcium formed by electrospray ionization. Six water molecules coordinate directly to the calcium dication, whereas the seventh water molecule is incorporated into a second solvation shell. Spectral features indicate the presence of multiple structures of Ca(H2O)(7)2+ in which outer-shell water molecules accept either one (single acceptor) or two (double acceptor) hydrogen bonds from inner-shell water molecules.

Identification of cremains using X-ray diffraction spectroscopy and a comparison to trace element analysis.

The ability to distinguish human cremains from filler materials can be important in a variety of situations, the most notorious recent example being the Tri-State Crematorium incident. However, the majority of the papers in the recent literature present methods that rely on trace or minor element analysis, usually followed by a statistical or variable cluster analysis, to determine attribution. This approach is inherently risky, as there is significant natural variation in the trace and minor element body burdens within the human population and no real baseline for comparison.

The role of skirt geometry of dental crowns on the mechanics of failure: experimental and numerical study.

Dental crown structures were modelled using a curved bi-layer system consisting of a brittle glass coating on a compliant polymeric substrate, to illustrate the role of skirt geometry on the mechanics of failure evolution. The geometries of the samples were varied by tapering the skirts of the glass shells in different lengths and thicknesses. The failure of these samples was investigated under single-cycle axial loading tests using an indenter of low elastic modulus.

Margin failures in crown-like brittle structures: off-axis loading.

The effect of off-axis loading of compliant indenters on the initiation of cracks at the margins of dental crown-like dome structures consisting of glass shells back-filled with an epoxy resin is examined. As in previous studies on similar structures but with strictly axial loading, cracks can be made to initiate and propagate from the margins around the dome faces into a "semi-lunar" fracture pattern characteristic of some all-ceramic crown failures. In this study, balsa wood and teflon disk indenters are used to provide the off-axis loading, at 45 degrees to the dome axis.

Oral eosinophilic granulomas in tigers (Panthera tigris)--a collection of 16 cases.

Oral eosinophilic granulomas were diagnosed in 16 tigers (Panthera tigris). All lesions were located on the hard or soft palate and typically consisted of flat or slightly raised circular ulcers. Histologic features of these lesions were essentially identical to those seen in oral eosinophilic granulomas of domestic cats and dogs.

Mortality of captive black-footed ferrets (Mustela nigripes) at Smithsonian's National Zoological Park, 1989-2004.

Black-footed ferret (Mustela nigripes) mortality was investigated retrospectively based on the pathology records of 107 captive animals held at Smithsonian's National Zoological Park from 1989 to 2004. The majority of deaths in neonates were due to cannibalism (n = 42; 64.6%) and maternal trauma (n = 11; 16.