cssi/SciSciGPT-SciSciNet huggingface dataset:
An improved neutron collimator for brain tumor irradiations in clinical boron neutron capture therapy

To improve beam penetration into a head allowing the treatment of deeper seated tumors, two neutron collimators were built sequentially and tested for use in the clinical boron neutron capture therapy (BNCT) program at the epithermal neutron irradiation facility of the Brookhaven Medical Research Reactor. The collimators were constructed from lithium-impregnated polyethylene, which comprises Li2CO3 powder (approximately 93% enriched isotopic 6Li) uniformly dispersed in polyethylene to a total 6Li content of 7.0 wt. %. The first collimator is 7.6 cm thick with a conical cavity 16 cm in diameter on the reactor core side tapering to 8 cm facing the patient's head. The second collimator is 15.2 cm thick with a conical cavity 20 cm in diameter tapering to 12 cm. A clinical trial of BNCT for patients with malignant brain tumors is underway using the first collimator. Results of phantom dosimetry and Monte Carlo computations indicate that the new 15.2 cm thick collimator will improve the neutron beam penetration. Thus, the second collimator was made and will be used in an upcoming clinical trial. In-air and in-phantom mixed-field dosimetric measurements were compared to Monte Carlo computations for both collimators. The deeper penetration is achieved but at a sacrifice in beam intensity. In this report, a performance comparison of both collimators regarding various fluence rate and absorbed dose distributions in a head model is presented and discussed.
A functional RANKL polymorphism associated with younger age at onset of rheumatoid arthritis

Objective We previously observed the association of the co-occurrence of the HLA–DRB1 shared epitope (SE) and RANKL single-nucleotide polymorphisms (SNPs) with younger age at the onset of rheumatoid arthritis (RA) in 182 rheumatoid factor (RF)–positive European American patients with early-onset RA. The aim of this study was to fine-map the 48-kb RANKL region in the extended cohort of 210 European American RF-positive patients with early RA, to seek replication of RA-associated SNPs in additional RA cohorts of 501 European Americans and 298 African Americans, and to explore the functional consequences of RA-associated SNPs. Methods SNP genotyping was conducted using pyrosequencing or TaqMan polymerase chain reaction (PCR) assays. Associations of rs7984870 with RANKL expression in plasma, peripheral blood mononuclear cells, and isolated T cells were quantified using enzyme-linked immunosorbent assay and reverse transcription–PCR. Site-directed mutagenesis of rs7984870 within the 2-kb RANKL promoter was performed to drive the luciferase reporter gene in osteoblast and stromal cell lines. Interaction of DNA and protein was determined by electrophoretic mobility shift assay. Results A single promoter SNP, rs7984870, was consistently significantly associated with earlier age at the onset of RA in 3 independent seropositive (RF or anti–cyclic citrullinated peptide antibody) RA cohorts but not in seronegative RA patients. The C risk allele of rs7984870 conferred 2-fold higher plasma RANKL levels in RF-positive patients with RA, significantly elevated RANKL messenger RNA expression in activated normal T cells, and increased promoter activity after stimulation in vitro via differential binding to the transcription factor SOX5. Conclusion The RANKL promoter allele that increased transcription levels upon stimulation might promote interaction between activated T cells and dendritic cells, predisposing to a younger age at the onset of RA in seropositive European American and African American patients.
Infrared laser-initiated dissociation of propane and ethylene.

Propane decomposition by IR laser radiation at 10.6 μm was studied with a pulsed multimode TEA CO2 laser and also with a cw CO2 laser. Propane molecules do not undergo appreciable photochemical decomposition via multiphoton absorption processes for laser fluences up to 40 J/cm2 (400 MW/cm2). At higher fluences plasmas are formed which cause extensive dissociation. If the radiation is incident on an aluminum surface in contact with propane, the molecules dissociate at an energy fluence as low as 2 J/cm2 (20 MW/cm2). This is considered to be due to plasma formation in the propane near the surface.
Selecting neighbor sets for texture classification using multispectral images

In this paper, we design a decision rule to select optimized neighbor sets for multispectral images. We assume that multispectral images can be modeled by parametric Gaussian Random Fields. From a class of such models with different neighbor sets, we choose the best representation employing bayesian methods. The chosen model accounts for interactions within each of the spectral bands as well as the interaction between different spectral bands in a multispectral image. We evaluate the performance of the neighbor sets for multispectral texture classification.
Simulation of a steady-state integrated human thermal system.

The mathematical model of an integrated human thermal system is formulated. The system consists of an external thermal regulation device on the human body. The purpose of the device (a network of cooling tubes held in contact with the surface of the skin) is to maintain the human body in a state of thermoneutrality. The device is controlled by varying the inlet coolant temperature and coolant mass flow rate. The differential equations of the model are approximated by a set of algebraic equations which result from the application of the explicit forward finite difference method to the differential equations. The integrated human thermal system is simulated for a variety of combinations of the inlet coolant temperature, coolant mass flow rate, and metabolic rates. Two specific cases are considered: (1) the external thermal regulation device is placed only on the head and (2) the devices are placed on the head and the torso. The results of the simulation indicate that when the human body is exposed to hot environment, thermoneutrality can be attained by localized cooling if the operating variables of the external regulation device(s) are properly controlled.
Peer-to-peer control architecture for multiuser haptic collaboration over undirected delayed packet-switching network

We propose a novel peer-to-peer distributed control architecture for shared haptic collaboration among remotely-located users over undirected packet-switching network (e.g. Internet) with inter-user communication delay. The proposed architecture is distributed, in that each user simulates and interacts with its own local copy of the shared virtual environment. Spring connection among the local copies and local damping are used, which, together, under a certain condition, achieve configuration synchronization among the local copies while enforcing discrete-time passivity of the total peer-to-peer architecture, thereby, rendering the architecture portable/scalable for any (passive) users/devices and ensuring its interaction stability be user/device-invariant. The issue of optimizing communication network is also addressed with some relevant experimental results.
A Scanning Electron Diffraction Study of Vapor-Deposited and Ion Implanted Thin Films of Ge (II)

The structure of Ge films evaporated by several methods onto room temperature substrates of NaCl and films which have been ion implanted with 3 × 1015, 30 to 40 ke V Ge74 has been investigated via a scanning electron diffraction instrument with electron energy filtering. The radial distribution functions of all films are very similar and exhibit strong correlation peaks at 2.45, 4.00, and (4.85 ± 0.075) A with coordinations of 4, 12, and ≈ 7, respectively. The remaining major peaks for higher r deviate substantially from the diamond cubic form of Ge. From the RDF analysis a density ratio ϱ0/ϱcryst of 0.86 to 0.95 is determined. Thermal anneal experiments showed that the films may be annealed to a density of ≈0.97 of crystalline density without crystallization. Amorphous films which have been ion implanted with the same energy and dose as the polycrystalline films show a considerable concentration of pores and voids of a maximum diameter of 100 A. The RDF, however, is identical to the as-deposited film with the exception of some changes in the correlation for r greater than 11 A. Die Struktur dunner Ge-Schichten, die auf verschiedene Arten auf NaCl-Trager bei Zimmertemperatur aufgedampft wurden und die mit 3 × 1015 (30 bis 40 keV) Ge74-Ionen beschossen wurden, wird mit Hilfe einer Abtastelektronenbeugungsanlage mit Elektronenenergiefilter untersucht. Die Atomverteilungskurven (RDF) aller Schichten sind sich sehr ahnlich und zeigen starke Korrelationsmaxima bei 2,45; 4,00 und (4,85 ± 0,075) A mit Koordinationszahlen von 4, 12 bzw. ≈7. Die ubrigen Hauptmaxima fur grosere r unterscheiden sich bedeutend von denen des (Diamant)kubischen Ge. Mit Hilfe der Atomverteilungsanalyse (RDF) wird das Dichteverhaltnis (ϱ0/ϱkrist) zu 0,86 bis 0,95 ermittelt. Heizversuche zeigten, das die Schichten ohne Kristallbildung bis zur Kristalldichte von 0,97 getempert werden konnten. Amorphe Schichten, die mit Ionen gleicher Energie und Dosis wie polykristalline Schichten beschossen wurden, enthielten eine hohe Konzentration von Poren und Hohlraumen mit maximalem Durchmesser von 100 A. Die Atomverteilungskurven (RDF) dieser Schichten und der aufgedampften sind bis auf kleine Anderungen in den Korrelationsmaxima fur r groser als 11 A identisch.
The surface free energies of talc and pyrophyllite

The components of the interfacial surface tension of talc and pyrophyllite were determined by measuring the rate of the capillary rise of a number of liquids through thin, sedimented deposits of the powdered minerals. The rate of capillary rise of a liquid in a powder is related to the contact angle between the liquid and the solid by the Washburn equation. The contact angles thus derived were used to determine the apolar (Lifshitzvan der Waals) component, γ LW , and the polar, electronacceptor and electron-donor parameters, γ ⊕ and γ ⊖ respectively, of the Lewis acid/base component of the total interfacial surface energy using the Young equation. The values of γ LW for talc and pyrophyllite (31.5 and 34.4 mJ/m2) are slightly smaller than for smectite clay minerals (e.g., the value for hectorite is 39.9 mJ/m2), the electron donor parameter values are roughly comparable for talc and pyrophyllite (γ ⊕ = 2.4 and 1.7 mJ/m2) as are the values of the electron acceptor parameter (γ ⊖ = 2.7 and 3.2 mJ/m2). The well-known hydrophobicity of these two minerals is due to the remarkably small value (for silicate minerals) of γ ⊖(γ⊕ is normally small or zero for silicates and many other oxides). The small values of both γ ⊕ and γ ⊖ mean that the Lewis acid/base interactions between talc or pyrophyllite and highly polar water molecules are very weak. In contrast, low-charge smectites, the minerals most similar chemically and structurally to talc and pyrophyllite, have much greater values of γ ⊖ (≥ 30 mJ/m2) and are hydrophyllic.
A new look at a time-worn system: oxidation of CuZn-SOD by H2O2.

Abstract This work summarizes observations from numerous investigators on the reaction of the copper-zinc superoxide dismutase with hydrogen peroxide at physiological pH in order to propose a likely sequence of events that leads to 2-oxo-histidine formation, copper loss, inactivation, and random and site-specific peptide fragmentation. New data is presented for the bovine liver enzyme that indicate copper is lost as the copper(I) form which immediately reacts with bathocuproine disulfonate to form the characteristic complex that absorbs at 485 nm. Studies in TRIS buffer ruled out the loss of copper(II) followed by reduction of the high potential copper(II)-bathocuproine disulfonate complex by buffer because TRIS is known not to reduce this complex. The rate of loss of copper(I) is not affected by the spin trap, 5,5′-dimethylpyrolline-N-oxide (DMPO), nor by replacing oxygen with argon in the reaction. In addition, changes in the native electrophoretic pattern that are correlated with copper loss and not peptide fragmentation are also unaffected by DMPO, argon, EDTA, or DTPA. These data are taken as indirect evidence that the formation of 2-oxo-histidine is the first oxidative event, unaffected by DMPO, that occurs at the bound oxidant and leads to loss of copper(I). Peptide fragmentation and the peroxidative activity of the dismutase are discussed in light of these observations.
The Jekyll-and-Hyde chemistry of Phaeobacter gallaeciensis

Emiliania huxleyi, an environmentally important marine microalga, has a bloom-and-bust lifestyle in which massive algal blooms appear and fade. Phaeobacter gallaeciensis belongs to the roseobacter clade of α-Proteobacteria, the populations of which wax and wane with that of E. huxleyi. Roseobacter are thought to promote algal growth by biosynthesizing and secreting antibiotics and growth stimulants (auxins). Here we show that P. gallaeciensis switches its secreted small molecule metabolism to the production of potent and selective algaecides, the roseobacticides, in response to p-coumaric acid, an algal lignin breakdown product that is symptomatic of aging algae. This switch converts P. gallaeciensis into an opportunistic pathogen of its algal host.
Diel behavior of iron and other heavy metals in a mountain stream with acidic to neutral pH: Fisher Creek, Montana, USA

Abstract Three simultaneous 24-h samplings at three sites over a downstream pH gradient were conducted to examine diel fluctuations in heavy metal concentrations in Fisher Creek, a small mountain stream draining abandoned mine lands in Montana. Average pH values at the upstream (F1), middle (F2), and downstream (F3) monitoring stations were 3.31, 5.46, and 6.80, respectively. The downstream increase in pH resulted in precipitation of hydrous ferric oxide (HFO) and hydrous aluminum oxide (HAO) on the streambed. At F1 and F2, Fe showed strong diel cycles in dissolved concentration and Fe(II)/Fe(III) ratio; these cycles were attributed to daytime photoreduction of Fe(III) to Fe(II), reoxidation of Fe(II) to Fe(III), and temperature-dependent hydrolysis and precipitation of HFO. At the near-neutral downstream station, no evidence of Fe(III) photoreduction was observed, and suspended particles of HFO dominated the total Fe load. HFO precipitation rates between F2 and F3 were highest in the afternoon, due in part to reoxidation of a midday pulse of Fe2+ formed by photoreduction in the upper, acidic portions of the stream. Dissolved concentrations of Fe(II) and Cu decreased tenfold and 2.4-fold, respectively, during the day at F3. These changes were attributed to sorption onto fresh HFO surfaces. Results of surface complexation modeling showed good agreement between observed and predicted Cu concentrations at F3, but only when adsorption enthalpies were added to the thermodynamic database to take into account diel temperature variations. The field and modeling results illustrate that the degree to which trace metals adsorb onto actively forming HFO is strongly temperature dependent. This study is an example of how diel Fe cycles caused by redox and hydrolysis reactions can induce a diel cycle in a trace metal of toxicological importance in downstream waters.
Fat oxidation and diabetes of obesity: The Randle hypothesis revisited

A hypothesis is presented that addresses the etiology of diabetes in the obese. Evidence from many areas of research suggests that ready availability of free fatty acids for oxidation by muscles and other tissues may lead to impairment of carbohydrate oxidation and lead to glucose intolerance as is seen in obesity and obese diabetics. In addition, free fatty acids can stimulate hepatic gluconeogenesis and alter pancreatic insulin release and subsequent metabolism, which may be the pathophysiological mechanism for these changes in obese diabetics. It is well-recognized that there are different anatomic forms of obesity and that risk of diabetes is much greater in those with abdominal rather than hip/thigh obesity. It may be that fat cells in abdominal depots (in these individuals) are more metabolically active, releasing greater amounts of free fatty acids (even after feeding when they should be suppressed), and the metabolism of these fatty acids leads to the changes described here, leading to overt diabetes.
The Cross: Church Symbol and Contest in Nineteenth-Century America

In 1834 the rector of St. Mary's Episcopal Church in Burlington, New Jersey desired to place a cross atop his newly-refurbished sanctuary. No ordinary rector, George Washington Doane also served as the Episcopal bishop of New Jersey. Shortly after taking charge of St. Mary's in 1833, he and his vestry had decided to renovate their old church, and their ambitious new design featured a cruciform plan with Greek details, including a pediment adorned with lotus leaves and a tower “derived from that built at Athens… commonly called the Tower of the Winds.” But when Doane carried out the plans for “an enriched Greek Cross” to be mounted on the roof, the community stood aghast. A local Presbyterian minister chronicled the confrontation, and he began by asserting that most of St. Mary's vestrymen had originally approved the designs without “noticing the Cross at the time.” The project was thus completed, and to the vestry's “great surprise, as well as that of many in the community, of all ‘denominations’—lo! a Cross made quite a Catholic appearance on the apex of the pediment!” Controversy arose, “both in the Vestry and out of it,” and “after a very warm meeting, one of the Vestry shortly after declared that unless the Cross was taken down very soon, it should be pulled down.”
Interfacial Delamination Between Through Silicon Vias (TSVs) and Silicon Matrix

Recently, three-dimensional (3-D) integration with through silicon vias (TSVs) has emerged as an effective solution for interconnect structures beyond the 32-nm technology node in microelectronics. Among others, thermo-mechanical reliability is a key concern for the development of TSV structures used in 3-D interconnects. This paper examines the thermal stress-induced delamination between through silicon via (TSV) and the silicon matrix. First, the driving force for TSV delamination was derived for a long crack at the steady state, and then the analytical solutions were validated using finite element analysis (FEA). The analytical solutions and simulation results were found to be in good agreement at the steady state, and together they suggested a fracture mechanism to account for the TSV delamination observed. The analytical solution further provided a basic framework for studying the impact of materials, process and structural design on reliability of the TSV structure. In particular, we found that reducing the thermal mismatch and TSV diameter yield definite advantages in lowering the crack driving force for TSV delamination. Such driving force can also be controlled by introducing an annular metal filling or a dielectric liner between TSV and the Si matrix. Finally, the TSV protrusion phenomenon during thermal cycles was investigated. The interfacial delamination was found to initiate during a cooling process and to develop under a subsequent heating process, causing TSVs to protrude from the silicon matrix after repeated thermal cycles.Copyright © 2010 by ASME
Crystallographic Orientation-Aligned ZnO Nanorods Grown by a Tin Catalyst

Well-aligned ZnO nanorods with identical crystallographic orientation have been synthesized using a vapor transport deposition process. Orientation-ordered nanorods grow normal to the c planes of t...
Procurement of spore‐free Bacillus anthracis for molecular typing outside of BSL3 environment

Aims: To (i) develop a protocol that would eliminate or greatly reduce sporulation within Bacillus anthracis vegetative cells, and (ii) harvest an adequate number of cells and sufficient DNA suitable for molecular methods including Riboprint® analysis and pulse field gel electrophoresis (PFGE). Methods and Results: Seven strains of B. anthracis (Ames, French B2, Heluky, Kruger, Pasteur, Sterne, and Vollum) were grown at 37, 42 and 45°C under normal air, enhanced CO2, microaerophilic, and anaerobic conditions on solid media and subcultured in two broths with and without supplements. The bacterial cells were centrifuged and washed. Slides made from the cell pellets were stained with Malachite Green and observed for the presence of spores. Cell preparations were subjected to 80°C for 30 min and processed for and analysed by either Riboprinter® or PFGE. Multiple pellets of each strain were processed, stained, placed onto solid culture media, incubated for 7 days and observed for growth. The cell preparations yielded clear and reproducible results with both molecular methods. None of the cell preparations yielded growth on the culture media. Conclusions: This method eliminated viable spores in cell preparations of B. anthracis, yet still allowed the growth of vegetative cells to provide sufficient DNA suitable for analysis by Riboprinter® and PFGE. Significance and Impact of the Study: This method will provide safe cell preparations, prevent instrument contamination, and may be useful for other aerobic and anaerobic spore-formers.
Visual attention, behavioral inhibition and speech/language outcomes in deaf children with cochlear implants.

We investigated relations between sustained visual attention, behavioral inhibition skills, and speech–language outcomes in prelingually deaf children who use cochlear implants (CIs) using two computerized continuous performance tasks (CPTs). One test measured their ability to sustain visual attention to a string of numbers and another test measured their ability to delay a behavioral response. Performance on latter task was related to postimplant scores on tests of vocabulary knowledge, language skills, and speech intelligibility. We conclude that behavioral inhibition skills of prelingually deaf children are related to several audiological outcome measures in deaf children with CIs. Our findings suggest that further investigation is warranted into executive functions and subvocal rehearsal skills of deaf children with CIs.
Mapping composite vulnerability to groundwater arsenic contamination: an analytical framework and a case study in India

Groundwater arsenic (As) contamination affects millions of people in South Asia. In this paper, we propose a composite vulnerability framework to identify, for mitigation, the population who are at the highest risk of suffering adverse impacts from exposure to As and warrant mitigation measures. Bihar, India, which was selected for the case study, has large areas with As concentrations far exceeding the upper limits of acceptable level of As in drinking water. Drawing on the existing social science research, we identify a host of socioeconomic and demographic variables, in addition to As concentration in groundwater, which compound a community’s vulnerability to the adverse effects of As. The result is a “composite vulnerability index,” which consists of biophysical, socioeconomic, and demographic factors that collectively determine a community’s overall vulnerability to As. Additionally, using geographic information systems (GIS), we represent the composite vulnerability index visually through a set of maps, which highlight the interaction between different community characteristics to generate unique community vulnerability profiles. In summary, this paper outlines a systematic approach to understanding vulnerability to groundwater As, as both social and natural construct, which can be applied to different geographic areas, and to improving decision making and planning pertaining to diverse environmental problems.
Noroviruses — Challenges to Control

Norovirus infections are worldwide in distribution and affect all age groups. Dr. Raphael Dolin writes that the biologic, physicochemical, and epidemiologic features of noroviruses present a serious challenge for infection control.
Uranium passivation by C + implantation: A photoemission and secondary ion mass spectrometry study

Implantation of 33 keV C{sup +} ions into polycrystalline U{sup 238} with a dose of 4.3 x 10{sup 17} cm{sup -2} produces a physically and chemically modified surface layer that prevents further air oxidation and corrosion. X-ray photoelectron spectroscopy and secondary ion mass spectrometry were used to investigate the surface chemistry and electronic structure of this C{sup +} ion implanted polycrystalline uranium and a non-implanted region of the sample, both regions exposed to air for more than a year. In addition, scanning electron microscopy was used to examine and compare the surface morphology of the two regions. The U 4f, O 1s and C 1s core-level and valence band spectra clearly indicate carbide formation in the modified surface layer. The time-of-flight secondary ion mass spectrometry depth profiling results reveal an oxy-carbide surface layer over an approximately 200 nm thick UC layer with little or no residual oxidation at the carbide layer/U metal transitional interface.
Oestrogen receptors in androgen or oestrogen sterilized female rats.

TREATMENT of pubertal female rats with androgen or oestrogen produces sterility and reduces sexual receptivity in a high percentage of the animals. These hormones seem to alter the normal function of the preoptic—anterior hypothalamic region1–3, which—apparently undifferentiated at birth—is involved in: (1) producing the cyclic ovulatory surge of gonadotropin resulting in ovulation2, and (2) regulating mating behaviour in the female rat4. When allowed to differentiate normally, it regulates the cyclic release of gonadotropin, which is necessary for the normal pattern of sexual behaviour in the female rat. Early treatment with oestrogen or androgen causes the preoptic area to become refractory to both intrinsic and extrinsic activation by stimuli which would usually result in ovulation5.
Differences in response rates between mail, e-mail, and telephone follow-up in hand surgery research

There is a need to determine the difference in response to mail, e-mail, and phone in clinical research surveys. We enrolled 150 new and follow-up patients presenting to our hand and upper extremity department. Patients were assigned to complete a survey by mail, e-mail, or phone 3 months after enrollment, altering the follow-up method every 5 patients, until we had 3 groups of 50 patients. At initial enrollment and at 3 month follow-up (range 2–5 months), patients completed the short version of the Disabilities of the Arm, Shoulder, and Hand questionnaire (QuickDASH), the short version of the Patient Health Questionnaire (PHQ-2), the Pain Self-Efficacy Questionnaire (PSEQ), and rated their pain intensity. The percent of patients that completed the survey was 34 % for mail, 24 % for e-mail, and 80 % for phone. Factors associated with responding to the survey were older age, nonsmoking, and lower pain intensity. Working full-time was associated with not responding. The response rate to survey by phone is significantly higher than by mail or e-mail. Younger age, smoking, higher pain intensity, and working full-time are associated with not responding. Type of study/level of evidence: Prognostic I
A Sialyltransferase Mutant with Decreased Donor Hydrolysis and Reduced Sialidase Activities for Directly Sialylating Lewisx

Glycosyltransferases are important catalysts for enzymatic and chemoenzymatic synthesis of complex carbohydrates and glycoconjugates. The glycosylation efficiencies of wild-type glycosyltransferases vary considerably when different acceptor substrates are used. Using a multifunctional Pasteurella multocida sialyltransferase 1 (PmST1) as an example, we show here that the sugar nucleotide donor hydrolysis activity of glycosyltransferases contributes significantly to the low yield of glycosylation when a poor acceptor substrate is used. With a protein crystal structure-based rational design, we generated a single mutant (PmST1 M144D) with decreased donor hydrolysis activity without significantly affecting its α2-3-sialylation activity when a poor fucose-containing acceptor substrate was used. The single mutant also has a drastically decreased α2-3-sialidase activity. X-ray and NMR structural studies revealed that unlike the wild-type PmST1, which changes to a closed conformation once a donor binds, the M144D mutant structure adopts an open conformation even in the presence of the donor substrate. The PmST1 M144D mutant with decreased donor hydrolysis and reduced sialidase activity has been used as a powerful catalyst for efficient chemoenzymatic synthesis of complex sialyl Lewis(x) antigens containing different sialic acid forms. This work sheds new light on the effect of donor hydrolysis activity of glycosyltransferases on glycosyltransferase-catalyzed reactions and provides a novel strategy to improve glycosyltransferase substrate promiscuity by decreasing its donor hydrolysis activity.
Forecast comparisons of four models of U.S. interest rates

In this paper we compare the out of sample forecasts from four alternative interest rate models based on expanding information sets. The random walk model is the most restrictive. The univariate time series model allows for a richer dynamic pattern and more conditioning information on own rates. The multivariate time series model permits a flexible dynamic pattern with own- and cross-series information. Finally, the forecasts from the MPS econometric model depend on the full model structure and information set. In theory, more information is preferred to less. In practice, complicated misspecified models can perform much worse than simple (also probably misspecified) models. For forecasts evaluated over the volatile 1970s the multivariate time series model forecasts are considerably better than those from simpler models which use less conditioning information, as well as forecasts from the MPS model which uses substantially more conditioning information but also imposes ‘structural’ economic restrictions.
Effect of vitamin C deficiency on healed wounds.

SummaryWhen young adult guinea pigs bearing linear laparotomy wounds which had healed under normal conditions for 6 weeks were subjected to an ascorbic acid-free dietary regimen for approximately 26 days, severe changes were observed in the scar tissue area. The changes consisted of fibroblastic proliferation, regression of connective tissue elements, and of hemorrhages. The wounds of pair-fed and ad lib. control animals presented normal healing. The results indicate that adequate ascorbic acid intake is required not only for normal healing in the early post wound period but also for the maintenance of the scar tissue which has formed in healed wounds over a period of many weeks.
A generalized allosteric mechanism for cis-regulated cyclic nucleotide binding domains.

Cyclic nucleotides (cAMP and cGMP) regulate multiple intracellular processes and are thus of a great general interest for molecular and structural biologists. To study the allosteric mechanism of different cyclic nucleotide binding (CNB) domains, we compared cAMP-bound and cAMP-free structures (PKA, Epac, and two ionic channels) using a new bioinformatics method: local spatial pattern alignment. Our analysis highlights four major conserved structural motifs: 1) the phosphate binding cassette (PBC), which binds the cAMP ribose-phosphate, 2) the “hinge,” a flexible helix, which contacts the PBC, 3) the β2,3 loop, which provides precise positioning of an invariant arginine from the PBC, and 4) a conserved structural element consisting of an N-terminal helix, an eight residue loop and the A-helix (N3A-motif). The PBC and the hinge were included in the previously reported allosteric model, whereas the definition of the β2,3 loop and the N3A-motif as conserved elements is novel. The N3A-motif is found in all cis-regulated CNB domains, and we present a model for an allosteric mechanism in these domains. Catabolite gene activator protein (CAP) represents a trans-regulated CNB domain family: it does not contain the N3A-motif, and its long range allosteric interactions are substantially different from the cis-regulated CNB domains.
Probable Adult Polyglucosan Body Disease

Adult polyglucosan body disease is a clinicopathologic entity characterized by progressive upper and lower motor neuron dysfunction, sensory loss in the lower extremities, sphincter dysfunction, and occasionally dementia. Pathologically, numerous large polyglucosan bodies are noted in peripheral nerves, cerebral hemispheres, and the spinal cord, as well as in other systemic tissues. We present a case of probable adult polyglucosan body disease based on clinical history and examination, magnetic resonance images, and sural nerve biopsy findings.
Digital vs. conventional implant impressions: efficiency outcomes

Objectives The aim of this pilot study was to evaluate the efficiency, difficulty and operator's preference of a digital impression compared with a conventional impression for single implant restorations. Materials and methods Thirty HSDM second year dental students performed conventional and digital implant impressions on a customized model presenting a single implant. The outcome of the impressions was evaluated under an acceptance criteria and the need for retake/rescan was decided. The efficiency of both impression techniques was evaluated by measuring the preparation, working, and retake/scan time (m/s) and the number of retakes/rescans. Participants' perception on the level of difficulty for the both impressions was assessed with a visual analogue scale (VAS) questionnaire. Multiple questionnaires were obtained to assess the participants' perception on preference, effectiveness and proficiency. Results Mean total treatment time was of 24:42 m/s for conventional and 12:29 m/s for digital impressions (P < 0.001). Mean preparation time was of 4:42 m/s for conventional and 3:35 m/s for digital impressions (P < 0.001). Mean working time including retakes/rescans demanded 20:00 m/s for conventional vs. 8:54 m/s for digital impression (P < 0.001). On a 0–100 VAS scale, the participants scored a mean difficulty level of 43.12 (±18.46) for conventional impression technique and 30.63 (±17.57) for digital impression technique (P = 0.006). Sixty percent of the participants preferred the digital impression, 7% the conventional impression technique and 33% preferred either technique. Conclusions Digital impressions resulted in a more efficient technique than conventional impressions. Longer preparation, working, and retake time were consumed to complete an acceptable conventional impression. Difficulty was lower for the digital impression compared with the conventional ones when performed by inexperienced second year dental students.
A Computational Model of the Cerebellum

A highly detailed computational model of mammalian cerebellum has been developed. It is being compared to physiological recordings for validation purposes. The model is also being used to study the relative contributions of each component to cerebellar processing.
EPOSee &#8212; A Tool For Visualizing Software Evolution

Software archives are a rich source of information about the development process of a software system. Using data mining techniques rules can be extracted from these archives. Rules can either be association rules which mean that software items have been changed together with a certain probability or sequence rules which mean items have been changed one after the other. The change frequency (support) as well as the change probability (confidence) of a given rule are both metrics used for visualizing the strength of a rule. EPOSee is a tool designed to interactively explore these kinds of rules. To this end we extended standard visualization techniques for association and sequence rules to also show the hierarchical order of items. Clusters and outliers in the resulting visualizations provide interesting insights into the relation between the temporal development of a system and its static structure
Breaking the Radiation Damage Limit with Cryo-SAXS

Small angle x-ray scattering (SAXS) is a versatile and widely used technique for obtaining low-resolution structures of macromolecules and complexes. SAXS experiments measure molecules in solution, without the need for labeling or crystallization. However, radiation damage currently limits the application of SAXS to molecules that can be produced in microgram quantities; for typical proteins, 10–20 μL of solution at 1 mg/mL is required to accumulate adequate signal before irreversible x-ray damage is observed. Here, we show that cryocooled proteins and nucleic acids can withstand doses at least two orders of magnitude larger than room temperature samples. We demonstrate accurate T = 100 K particle envelope reconstructions from sample volumes as small as 15 nL, a factor of 1000 smaller than in current practice. Cryo-SAXS will thus enable structure determination of difficult-to-express proteins and biologically important, highly radiation-sensitive proteins including light-activated switches and metalloenzymes.
Magnesium use in the treatment of acute myocardial infarction in the United States (observations from the Second National Registry of Myocardial Infarction).

The use of magnesium in patients with acute myocardial infarction (AMI) is debated, largely as a result of conflicting data from randomized controlled trials. This study evaluated the use and impact on mortality of intravenous magnesium in the treatment of patients with AMI in the United States based on data from the Second National Registry of Myocardial Infarction. Only 5.1% of 173,728 patients from 1,326 hospitals received intravenous magnesium within the first 24 hours after an AMI, and this was more common in the 59,798 patients who received thrombolytic therapy or who underwent primary percutaneous transluminal coronary angioplasty (PTCA) or coronary bypass grafting (CABG) than in the 113,930 patients who did not receive any reperfusion therapy (8.5% vs 3.4%, p 1.2, p <0.001). Magnesium use was associated with increased mortality (odds ratio 1.25, 95% confidence interval 1.12 to 1.34) and with a higher mortality in patients without initial reperfusion therapy (20.2% vs 13.2%, p <0.0001) or who underwent primary PTCA or CABG (10.2% vs 7.3%, p = 0.002), but not in patients who received thrombolytic therapy (6.2% vs 5.9%, p = NS). Thus, magnesium is used infrequently in the treatment of AMI and may be associated with worse outcome.
Local Rigidity of Partially Hyperbolic Actions. II: The Geometric Method and Restrictions of Weyl Chamber Flows on SL(n, ℝ)/Γ

We consider the restriction α0,G of the Weyl chamber flow on SL(n,R)/Γ (where Γ is a cocompact lattice) to a closed subgroup G isomorphic to Z × R, k + l ≥ 2 of the group D+ of positive diagonal matrices which contains a lattice in a twodimensional plane in general position. We prove that any C small smooth perturbation of the action α0,G is differentiably conjugate to a standard perturbation which arises from a perturbation of the embedding Z × R → D+. We introduce a new method in rigidity of actions of higher rank abelian groups based on the study of combinatorial structure of the the web of Lyapunov (unipotent) foliations. Insights from the classical algebraic K-theory play a crucial role in establishing stability properties of that web. The method has applications to other classes of partially hyperbolic algebraic actions and is complementary to the other new analytic method which we introduced in the first paper of this series.
Estimating the Value of Social Security Retirement Benefits

The authors start with a simple question: what is the value of an individual9s assets that can be used to satisfy retirement income needs, focusing more specifically on Social Security benefits? Consistent with an approach introduced in earlier works published in The Journal of Wealth Management, they then ask how these benefits affect the individual9s current asset mix. In particular, they delve further into earlier conclusions that the present value of projected Social Security payments be included as a 9bond9 in personal portfolios. They note that individuals9 portfolios are usually substantially different when the value of Social Security is included than when it is excluded, and demonstrate that the profession has been miscalculating individuals9 “true” portfolios by excluding Social Security. If individuals optimize their traditional portfolios, which exclude Social Security, then they have excessively conservative, sub-optimal true -portfolios.
Positive Trends and Opportunities for Sustainable Design in Operations Management Textbooks With Examples from the Electronics Industry

In recent editions of operations management textbooks, sections have been added on topics related to sustainable design. Many of the textbook discussions illustrate design for environment, remanufacturing, and recycling with examples from the electronics industry. Building on this positive trend, this paper points out how educators can further enhance student learning by expanding existing exercises and discussions with additional resources. The paper concludes with a call to integrate sustainable design concepts into operations management and other non-environmental engineering fields that impact product design.
Cell Wall, Cytoskeleton, and Cell Expansion in Higher Plants

To accommodate two seemingly contradictory biological roles in plant physiology, providing both the rigid structural support of plant cells and the adjustable elasticity needed for cell expansion, the composition of the plant cell wall has evolved to become an intricate network of cellulosic, hemicellulosic, and pectic polysaccharides and protein. Due to its complexity, many aspects of the cell wall influence plant cell expansion, and many new and insightful observations and technologies are forthcoming. The biosynthesis of cell wall polymers and the roles of the variety of proteins involved in polysaccharide synthesis continue to be characterized. The interactions within the cell wall polymer network and the modification of these interactions provide insight into how the plant cell wall provides its dual function. The complex cell wall architecture is controlled and organized in part by the dynamic intracellular cytoskeleton and by diverse trafficking pathways of the cell wall polymers and cell wall-related machinery. Meanwhile, the cell wall is continually influenced by hormonal and integrity sensing stimuli that are perceived by the cell. These many processes cooperate to construct, maintain, and manipulate the intricate plant cell wall—an essential structure for the sustaining of the plant stature, growth, and life.
Inhibition of N-Methyl-d-aspartate Receptors by Straight-Chain Diols: Implications for the Mechanism of the Alcohol Cutoff Effect

n-Alkanol inhibition of N-methyl-D-aspartate (NMDA) receptors exhibits a "cutoff" effect: alcohols with up to eight to nine carbon atoms inhibit the receptor, whereas larger alcohols do not. This phenomenon was originally proposed to result from size exclusion; i.e., alcohols above the cutoff are too large to bind to an amphiphilic site on the receptor. In the present study, 1,Omega-diols with 3 to 14 carbon atoms inhibited NMDA-activated current in Chinese hamster ovary and human embryonic kidney 293 cells transiently expressing NR1 and NR2B NMDA receptor subunits. Results of fluctuation analysis experiments were consistent with a similar mechanism of inhibition of NMDA-activated current by alcohols and diols. The average change in apparent energy of binding of the diols caused by addition of a methylene group was 2.1 kJ/mol, which is consistent with an important role of hydrophobic interactions. Because 1,Omega-diols with 9 to 14 carbons inhibited NMDA-activated current, despite having molecular volumes exceeding that at the cutoff point for 1-alkanols, a size exclusion mechanism seems inadequate to explain the cutoff effect. A disparity in hydrophobicity values at the cutoff for alcohols and diols, however, revealed that hydrophobicity could also not entirely explain the cutoff phenomenon. From these results, it seems that the cutoff effect on NMDA receptors results primarily from the inability of long-chain alcohols to achieve adequate concentrations at their site of action due to low aqueous solubility, although other factors may also contribute to the effect.
Introduction to biostatistics: Part 2, descriptive statistics

Descriptive statistics include measures of central tendency and variability. Measures of central tendency include mean, median, and mode. The mean is the arithmetic average of data from interval or ratio scales. The median reflects the 50th percentile score. The mode is the most frequently occurring value of a data distribution. Measures of variability include range, interquartile range, standard deviation, and standard error of the mean. The range describes the spread between the extreme values of data. Interquartile range is data included between the 25th and 75th percentile of a distribution. Standard deviation describes variability of data about the sample mean, while standard error of the mean helps describe the distribution of several sample means about a true population mean. Finally, confidence intervals, which are derived from the standard error of the mean, define an interval likely to include a true population value, based on sample statistical values and probability charceristics of data distributions.
A java middleware platform for resource-aware distributed applications

This paper reports the development of D-Raje (Distributed Resource-Aware Java Environment), a Java-based middleware platform that makes it possible to model and to monitor resources in a distributed environment. With this middleware, any kind of hardware or software resource can be modelled using standard Java objects, and services allow to discover local as well as remote resources, and to observe the state of these resources either locally or remotely. D-Raje is meant to ease the development of adaptive, security-oriented, or QoS-oriented Java applications, as well as the development of platforms capable of supporting such demanding applications.
A comprehensive cloud-based remote hearing diagnosis system

Although emerged for around a decade, tele-hearing systems have been limited to pure-tone audiometry because of the technical complexity involved in the other hearing test modalities. This paper presents a comprehensive remote hearing system that integrates two of the most needed test modalities: pure-tone audiogram and speech test. Inheriting the browserserver architecture from an earlier effort, the proposed system consists of an application server, audiologist terminal, and patient-side equipment, which further includes a commercial audiometer and an “in-house” console device that is capable of data and audio signal exchange required by speech tests and facilitates convenient communication between the audiologist and patient, making test sessions go smoothly.