cssi/SciSciGPT-SciSciNet huggingface dataset:
SU‐E‐T‐319: Radiochromic Film Characterization of a Small Animal Irradiator

Purpose: To characterize the output of a Cs‐137‐based Gammacell 40 Exactor Low Dose‐Rate Research Irradiator using radiochromic film measurements.Methods: Gafchromic EBT radiochromic film was used to characterize the the timer error, uniformity, penumbra, and scatter dose for a mouse irradiation device used in conjunction with a Cs‐137 irradiator with a nominal dose rate of 100.04cGy/min. Radiochromic film was chosen because of its good spatial resolution and relative insensitivity to radiation spectral changes. An Epson Expression 10000XL filmscanner was used to digitize the films, and generated images were imported into Matlab for analysis. To verify the calibration curve and to calculate timer error, a second set of films from the same batch were irradiated with a 4MV photon beam. Differences between the vendor supplied dose rate and Cs‐137 extrapolated dose rate were compared with Fricke dosimetry results. A uniformity film was placed in the irradiation chamber and exposed for 6 minutes. To measure dose under shielding attributed to scatter, films were cut to fit around the perimeter of the irradiation chamber and irradiated for 100 minutes. To measure the penumbra across the edge of a cerrobend blocking device,films were cut and placed across the block edges. Results: The timer error was estimated to be approximately 2.6sec. Uniformity of better than ±5% was observed both in horizontal and vertical film profiles. A scatter dose of approximately 10% of the irradiation dose was observed. The 20%–80% penumbra distance of 11.9mm was observed, measured from the dose profile in the horizontal dose plane Conclusions: Our study provides independent verification for a number of dosimetric properties of interest when designing mouse irradiation experiments. This was used to improve the dose computation in small animal studies for correlation of dose with biological effects, and improve accuracy of partial body dose estimates.
Combined electrophysiological, immunocytochemical and peptide release measurements in the hypothalamic slice

Abstract Sagittal hypothalamic slices were prepared from cycling female guinea pigs and incubated for 10–12 h during which time intracellular recordings were made from 274 arcuate and cell-poor zone (ARC-CPZ) neurons. Many of the cells exhibited spontaneous activity and a small percentage could be driven antidromically via median eminence stimulation and orthodromically via stria terminals stimulation. During the long-term recording, the effluent medium was collected in 30 of the experiments and radioimmunoassayed using a high-titer, conformational antisera for the peptide luteinizing hormone-releasing hormone (LH-RH). The findings revealed that LH-RH is released in detectable amounts from slices prepared from a single hypothalamus, that the amount of LH-RH released is dependent on the stage of the cycle, and that it can be stimulated by known secretagogues like prostaglandin E 2 . Following the electrophysiological experiments, the slices were fixed and processed for immunocytochemistry using a specific antisera (EL-14) for LH-RH. LH-RH neurons were stained throughout the ARC-CPZ area with intense fiber staining in the median eminence. These findings demonstrate that the hypothalamic slice preparation can be utilized for combined electrophysiological, immunocytochemical and peptide release measurements.
Saturn's cloud structure inferred from Cassini ISS

Abstract Using high-resolution Cassini ISS images with wavelengths ranging from the ultraviolet to the near infrared, we have retrieved Saturn’s atmospheric aerosol structure and properties for a broad range of latitudes in the southern hemisphere. The observations are consistent with two distinct layers of haze above a scattered cloud. Each layer is characterized by a vertical location, an optical thickness, and an effective mean particle size, all of which vary with latitude. The tropospheric haze is optically thickest and extends to the greatest heights (∼40 mbar) over the equator; its top surface is at significantly greater depths (∼150 mbar) at mid-latitudes. The height of the haze correlates well with position of the tropopause as indicated by the temperature field. Beneath this haze, we find a scattered denser cloud responsible for small-scale contrasts at an average depth of 1.75 ± 0.4 bar, with some features as deep as 2.5 bar or greater.
Faster Protein Splicing with the Nostoc punctiforme DnaE Intein Using Non-native Extein Residues

Inteins are naturally occurring intervening sequences that catalyze a protein splicing reaction resulting in intein excision and concatenation of the flanking polypeptides (exteins) with a native peptide bond. Inteins display a diversity of catalytic mechanisms within a highly conserved fold that is shared with hedgehog autoprocessing proteins. The unusual chemistry of inteins has afforded powerful biotechnology tools for controlling enzyme function upon splicing and allowing peptides of different origins to be coupled in a specific, time-defined manner. The extein sequences immediately flanking the intein affect splicing and can be defined as the intein substrate. Because of the enormous potential complexity of all possible flanking sequences, studying intein substrate specificity has been difficult. Therefore, we developed a genetic selection for splicing-dependent kanamycin resistance with no significant bias when six amino acids that immediately flanked the intein insertion site were randomized. We applied this selection to examine the sequence space of residues flanking the Nostoc punctiforme Npu DnaE intein and found that this intein efficiently splices a much wider range of sequences than previously thought, with little N-extein specificity and only two important C-extein positions. The novel selected extein sequences were sufficient to promote splicing in three unrelated proteins, confirming the generalizable nature of the specificity data and defining new potential insertion sites for any target. Kinetic analysis showed splicing rates with the selected exteins that were as fast or faster than the native extein, refuting past assumptions that the naturally selected flanking extein sequences are optimal for splicing.
Comparison of DOE-2 with temperature measurements in the Pala test houses

Abstract The predictions of version 2.1E of the DOE-2 program for building energy analysis have been compared with measurements in the Pala test houses near San Diego, CA. This work was part of the California Institute for Energy Efficiency ‘Alternatives to Compressor Cooling in California Transition Zones’ project in which DOE-2 was used for parametric analysis of cooling strategies that reduce peak electrical demand. To establish the validity of DOE-2 for this kind of analysis the program was compared with room air temperature measurements in a ‘low-mass’ house with conventional insulated stud wall construction and a ‘high-mass’ house with insulated concrete walls. To test different aspects of the DOE-2 calculation, four different unoccupied, unconditioned thermal configurations of these houses were considered: unshaded windows, shaded windows, white exterior surfaces, and forced night ventilation. In all cases DOE-2 agreed well with the air temperature measurements, with a mean deviation between simulation and measurement ranging from 0.2 to 1.0 K depending on configuration and type of house. Comparisons with inside surface temperature measurements also showed good agreement. Agreement between predictions and measurements improved when a more accurate calculation of foundation heat transfer was used, the ground surface temperature was calculated, and the normal 7-day ‘warm-up’ period in DOE-2 was extended to 11 days for the high-mass house.
Light hardon properties with improved staggered quarks

Abstract Preliminary results from simulations with 2+1 dynamical quark flavors at a lattice spacing of 0.09 fm are combined with earlier results ata = 0.13 fm. We examine the approach to the continuum limit and investigate the dependence of the pseudoscalar masses and decay constants as the sea and valence quark masses are separately varied.
Quantitative X‐ray fluorescence analysis of thin films using LAMA‐2

An improved version of the LAMA program for the quantitative analysis of composition and mass thickness of thin film materials by X-ray fluorescence (XRF) has been developed. The divergence and slow convergence problems occasionally experienced with the LAMA-1 program have been eliminated by using the linear approximation method and the algorithm of simultaneous refinement of composition and thickness to greatly increase its capability and performance. A study of over a hundred simulated thin films showed that the LAMA-2 program converged much faster than LAMA-1 and gave better accuracy. The efficiency of the program has been improved to the point where it is feasible to operate on a minicomputer.
Age-dependent effects of growth hormone on striped bass hybrids

Abstract 1. 1. The age-dependency of the effects of growth hormone on striped bass hybrids was investigated. 2. 2. The growth enhancement was higher in yearlings than in juveniles after weekly injection of the hormone. 3. 3. The analysis of total protein, RNA, DNA and amino acid profile in the muscle tissue indicated hormonestimulated hypertrophic growth and a possible need for essential amino acid supplementation in diet. 4. 4. Feeding rate was not stimulated whereas food conversion efficiency and intestinal amino acid absorption rate were significantly increased by the hormone treatment in an age-dependent manner. 5. 5. Possible reasons for these observations are discussed.
Indomethacin inhibits ovarian PGE secretion and gonadotropin-induced ovulation in a reptile (Anolis carolinensis)

Although prostaglandins (PGs) have been shown to play an important role in gonadotropin-induced ovulation in mammals, birds, and fishes, nothing is known about the role of PGs in reptilian ovulation. Females of the lizard Anolis carolinensis, each with a large vitellogenic ovarian follicle, were pretreated with an inert subcutaneous pellet or one containing indomethacin (an antiprostaglandin) at a delivery rate of 2.38 μg/lizard/day. Females in each pretreatment group were treated with subcutaneous injections, 7 h apart, of either vehicle alone or 25 μg porcine FSH. They then were sacrificed at 9, 12, and 24 h after the initial injection. After noting whether ovulation had occurred, ovaries from animals with an unovulated large (>5 mm diameter) follicle were incubated in 5 ml Anolis Ringer's for 1 h. The follicles then were examined histologically, and levels of PGE in the incubation medium were determined by radioimmunoassay. FSH significantly induced ovulation in a majority of females by 12 h, and indomethacin significantly reduced the number of FSH-induced ovulations at 12 h but not at 24 h. Thus, indomethacin delayed FSH-induced ovulation. Indomethacin also inhibited the preovulatory changes in histology of the follicular wall seen after FSH treatment alone and lowered PGE secretion at all time periods. Secretion of PGE was not influenced by FSH. Thus, prostaglandins may mediate or permit, at the ovarian level, the ovulatory influence of gonadotropin in this reptile.
Quality Control of Meteorological Data for the Chemical Stockpile Emergency Preparedness Program

The Chemical Stockpile Emergency Preparedness Program Meteorological Support Project ensures the accuracy and reliability of data acquired by meteorological monitoring stations located at seven U.S. Army chemical weapons depots where storage and weapons destruction (demilitarization) activities are ongoing. The data are delivered in real time to U.S. Army plume dispersion models, which are used to plan for and respond to a potential accidental release of a chemical weapons agent. The project provides maintenance, calibration, and audit services for the instrumentation; collection, automated screening, visual inspection, and analysis of the data; and problem reporting and tracking to carefully control the data quality. The resulting high-quality meteorological data enhance emergency response modeling and public safety.
Learning model solution to a problem in constrained optimization

Abstract Two modes of presentation, A and X , are assumed to be available for teaching a concept or association. Learning models are applied to answer the question: give that i trials have been allotted a priori to the first mode and j trials for the second mode, what sequencing of the A and X trials will yield the maximum proportion correct on a test after Trial i + j ? The schedules are rank-ordered on the basis of predicted proportion correct on the test, and these rankings sharply contrast the long-short model with the random-trial increment, two-operator linear, and one-element models.
Conditioned aversion after delay place conditioning with nicotine

Rats received subcutaneous injections of either nicotine (NIC; 0.05-0.8 mg/kg) or vehicle [VEH (phosphate buffer); 1 ml/kg] immediately after conditioning sessions in a place-conditioning paradigm (delay conditioning). NIC was paired for three delay-conditioning sessions with one environment of a three-compartment place-conditioning apparatus; VEH was paired with another environment. The subjects were then tested for place preference or aversion by determining the proportion of time spent in each compartment during a 15-min test session. Delay conditioning with NIC only produced a dose-related place aversion (greater time was spent in the VEH-paired chamber on test day). Place aversion was evident when NIC, 0.8 mg/kg, was administered either immediately or 5 min after conditioning sessions but not when given 15 min after conditioning. Chlorisondamine (5 micrograms, lateral ventricle), but not saline, administered 2 weeks prior to delay conditioning with 0.8 mg/kg NIC completely blocked the NIC-induced place aversion. These data suggest that delay conditioning with NIC produces place aversion by a central mechanism. Since standard conditioning (NIC injection immediately before the place-conditioning sessions) with NIC only produced dose-related place preferences (Fudala et al. 1985; Fudala and Iwamoto 1986), the time of administration of the unconditioned stimulus is a strong determinant of the place-conditioning effects of NIC.
53BP1 alters the landscape of DNA rearrangements and suppresses AID-induced B cell lymphoma

Deficiencies in factors that regulate the DNA damage response enhance the incidence of malignancy by destabilizing the genome. However, the precise influence of the DNA damage response on regulation of cancer-associated rearrangements is not well defined. Here we examine the genome-wide impact of tumor protein P53-binding protein 1 (53BP1) deficiency in lymphoma and translocation. While both activation-induced cytidine deaminase (AID) and 53BP1 have been associated with cancer in humans, neither AID overexpression nor loss of 53BP1 is sufficient to produce malignancy. However, the combination of 53BP1 deficiency and AID deregulation results in B cell lymphoma. Deep sequencing of the genome of 53BP1(-/-) cancer cells and translocation capture sequencing (TC-Seq) of primary 53BP1(-/-) B cells revealed that their chromosomal rearrangements differ from those found in wild-type cells in that they show increased DNA end resection. Moreover, loss of 53BP1 alters the translocatome by increasing rearrangements to intergenic regions.
Trans-auroral zone auroral infrasonic wave observations

Abstract The auroral infrasonic wave (AIW) substorm morphologies are compared for two trans-auroral zone stations, Inuvik, N.W.T. Canada (70°·4 dip lat) and College, Alaska (64°·6 dip lat), that lie along the same magnetic meridian with a north-south separation of 738 km. Statistical studies of the number of AIW received at College over a 5 yr period and at Inuvik over a 2 yr period as well as studies of individual auroral substorms observed at both stations have shown that in the morning sector many more AIW are observed at College than at Inuvik. This difference is related to the changing location of the westward auroral electroject with local time (Weins and Rostoker, 1973). The distribution of frequency of occurrence of AIW horizontal trace velocity V η is presented for College data together with a discussion of the effects on the distribution of (1) source speed, (2) wind shear, (3) geometry of the AIW mach cone with respect to the observing station, (4) the filtering of AIW with high ray path apogees and (5) the decrease in AIW amplitude with increasing mach number.
Derivation and Validation of a Simple Calculator to Predict Home Discharge after Surgery

Background Surgical patients and their physicians currently have tools to provide individualized prognostication for morbidity and mortality. For improved shared decision making, formal prediction of patient-centered outcomes is necessary. We derived and validated a simple, interview-based method to predict discharge home after surgery. Study Design We used the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) Patient User File for 2011. Derivation in general and vascular surgery patients undergoing inpatient surgery was completed using serial multiple logistic regression. Validation was performed within multiple surgical specialties. Results The derivation cohort included 88,068 patients, of whom 11,771 (13.4%) were not discharged home. The derived Home Calculator had excellent discrimination (c-statistic = 0.864) using 4 variables: age, American Society of Anesthesiologists' performance status, elective surgery, and preadmission residence. Validation cohorts had varying rates of home discharge as follows: general (63,826 of 71,591, 89.2%), vascular (12,319 of 16,102, 76.5%), gynecologic (16,603 of 17,005, 97.6%), urologic (13,662 of 14,435, 94.6%), orthopaedic (12,000 of 19,514, 61.5%), thoracic (4,467 of 5,092, 87.7%). The Home Calculator provided good to excellent discrimination in validation cohorts: general (c = 0.866), vascular (c = 0.800), gynecologic (c = 0.793), urologic (c = 0.814), orthopaedic (c = 0.876), and thoracic (c = 0.800). Comparable discrimination was demonstrated in sensitivity analyses in surgical patients admitted exclusively from home. Conclusions We derived and validated a simple Home Calculator that reliably predicts discharge to home after surgery and may be useful when counseling patients about postoperative course. Patient-centered tools such as this may allow physicians to better prepare patients and families for surgery and the recovery process.
Lifetime of asynchronous wireless sensor networks with multiple channels and power control

We consider wireless sensor networks with data collection traffic that apply asynchronous duty cycling to conserve energy, which is common in many environmental monitoring applications. Under these assumptions, the effect of overhearing dominates the energy consumption of the nodes. We propose multichannel operation with dynamic channel selection and power control for reducing the effect of overhearing in such asynchronous networks. A mathematical model is presented to calculate the maximum network lifetime under these considerations.
Interruption of SV40 Virus Tumorigenesis Using Irradiated Homologous Tumor Antigen.

SummaryX-irradiated SV40 transplant tumor or cell culture antigens were highly effective in preventing occurrence of homologous tumor in hamsters inoculated with SV40 virus when newborn. The X-irradiated immunizing tumor antigen was effective when given in a single dose as early as 34 days or as late as 76 days after SV40 virus was administered. The immunizing antigen was retained in tumor transplants in hamster for at least 20 passages and in cell culture of tumor for at least 38 passages. The significance of the findings in relation to protection against the hypothetical virus-induced tumor in man is discussed.
Diabetes insipidus, bone lesions, and new-onset red-brown papules in a 42-year-old man

HistoryA 42-year old Caucasian man was referred to theNationalInstitutes ofHealth(NIH) for evaluation.Hissymptoms began approximately 10 years before re-ferral with pituitary dysfunction that manifested asdiabetes insipidus, secondary hypogonadism, andhyperprolactinemia, treated with desmopressin andtestosterone gel. Eight years later, he began to expe-rience vertigo, dizziness, diplopia, and difﬁcultyfocusingandtracking.Thiswasfollowedbyprogress-ive left-sided weakness, poor coordination, and bal-ancedifﬁculties.Magneticresonanceimagingwithoutcontrast revealed multiple nonspeciﬁc white-matterlesions. Subsequent evaluation failed to identify anunderlyinginfectionorinﬂammatoryorigin.Systemiccorticosteroid therapy was initiated with minimalimprovement. Corticosteroids were tapered off 2monthslaterandthepatientnotednewasymptomaticskin lesions on his bilateral upper and lower extrem-ities, leading to reinitiation of systemic steroids andintroduction of interferon alfa. He denied fevers,chills, weight loss, or difﬁculty breathing.Physical examinationThe patient was a well-appearing Caucasian man.Cutaneous examination was notable for approxi-mately twenty 2- to 3-mm, ﬁrm, reddish-brown pap-ules scattered on the trunk and extremities, withgreater density on the front of his thighs (Fig 1).Diascopy revealed a yellowishhue. Ophthalmologicexamination was notable for nystagmus, saccadicpursuit,andmilddysmetria.Neurologicexaminationrevealed unsteady tandem gait, abnormal finger-to-nose pointing, and left-sided dysdiadochokinesia.Left arm strength was diminished (4/5). The oralmucosa was unremarkable. No lymphadenopathywas appreciated.HistopathologyA punch skin biopsy specimen of a papule on theleft thigh was obtained, and histology revealed amoderately dense dermal inﬁltrate of epithelioidhistiocytes characterized by rounded to slightlyelongated nuclei with inconspicuous nucleoli andmoderatetoabundanteosinophiliccytoplasm(Fig2,A). CD68 and CD163 immunochemistry highlightedthe lesional histiocytes (Fig 2, B). Lesional cells alsoshowedstrong,diffusestainingforfactorXIIIa(Fig2,C). CD1a and S100 immunostains were negative.Signiﬁcant diagnostic studiesRadiographs of the upper and lower extremitiesrevealed sclerotic lesions involving the metaphyseal
Direct determination of equilibrium potentials for hydrogen oxidation/production by open circuit potential measurements in acetonitrile.

Open circuit potentials were measured for acetonitrile solutions of a variety of acids and their conjugate bases under 1 atm H2. Acids examined were triethylammonium, dimethylformamidium, 2,6-dichloroanilinium, 4-cyanoanilinium, 4-bromoanilinium, and 4-anisidinium salts. These potentials, along with the pKa values of the acids, establish the value of the standard hydrogen electrode (SHE) potential in acetonitrile as −0.028(4) V vs the ferrocenium/ferrocene couple. Dimethylformamidium forms homoconjugates and other aggregates with dimethylformamide; open circuit potentials (OCPs) were used to quantify the extent of these reactions. Overpotentials for electrocatalytic hydrogen production and oxidation were determined from open circuit potentials and voltammograms of acidic or basic catalyst solutions under H2. For these solutions, agreement between OCP values and potentials calculated using the Nernst equation is within 12 mV. Use of the measured equilibrium potential allows direct comparison of catalytic s...
Laparoscopic Assisted Splenectomy for Treatment of Presumed Immune Thrombocytopenic Purpura: Initial Results

Objective To present the initial results of performance of laparoscopic splenectomy in two patients at Mayo Clinic Scottsdale. Design We describe two 18-year-old patients with idiopathic immune thrombocytopenic purpura and the technique of laparoscopic splenectomy used for treatment. Material and Methods For adequate visualization of the spleen and exposure of the upper midline area should urgent laparotomy become necessary, we position the patient supine with a sandbag under the left lower costal margin. Insertion of five 10-mm trocars facilitates placement of instruments. Dissection of the spleen is begun inferiorly. The splenic flexure of the colon is reflected inferiorly, and the spleen is rotated anterolaterally to allow division of the gastrosplenic ligament and the splenic hilum. Individual vessels are divided between clips, as are the short gastric vessels. Cautery is used for dividing the splenophrenic ligament. The spleen is placed in a plastic bag, and the open end of the bag is delivered through the umbilical incision, after which the spleen is morcellated and then removed. Considerable care must be exercised to ensure that the plastic bag is not punctured and that no ectopic splenic tissue is present. Results Both laparoscopic splenectomies were successful, and no intraoperative or postoperative complications occurred. After dismissal on postoperative day 3, the patients quickly resumed all activities. The platelet counts returned to normal. Conclusion These encouraging results support the use of laparoscopic splenectomy for immune thrombocytopenic purpura and suggest that this procedure may have a role in patients with other conditions of the spleen.
A descriptive analysis of National Library of Medicine-funded medical informatics training programs and the career choices of their graduates.

The initial 13 National Library of Medicine-supported medical informatics training programs and their graduates were studied to determine the program objectives, trainee selection factors, and curriculum components of the programs and the backgrounds and career choices of the trainees. All 13 programs and over 60% of the available population of trainees were studied. The analysis indicated that 1 ) the major objective was to train individuals in the applications of computer and information science to medicine; 2) the most frequent selection factor was the MD degree; 3) course work in computer science and a research project were the most common curriculum components; 4) 52% of the graduates selected academic careers; and 5) personal reasons most frequently influenced career choices. There is now a baseline of data that can be used in future studies. Key words: medical informatics; computers; National Library of Medicine; career choices. (Med Decis Making 1991;11:33- 37)
Mineralogy and Geochemistry of the Main Glauconite Bed in the Middle Eocene of Texas: Paleoenvironmental Implications for the Verdine Facies

The Main Glauconite Bed (MGB) is a pelleted greensand located at Stone City Bluff on the south bank of the Brazos River in Burleson County, Texas. It was deposited during the Middle Eocene regional transgression on the Texas Gulf Coastal Plain. Stratigraphically it lies in the upper Stone City Member, Crockett Formation, Claiborne Group. Its mineralogy and geochemistry were examined in detail, and verdine facies minerals, predominantly odinite, were identified. Few glauconitic minerals were found in the green pelleted sediments of the MGB. Without detailed mineralogical work, glaucony facies minerals and verdine facies minerals are easily mistaken for one another. Their distinction has value in assessing paleoenvironments. In this study, several analytical techniques were employed to assess the mineralogy. X-ray diffraction of oriented and un-oriented clay samples indicated a clay mixture dominated by 7 and 14A diffraction peaks. Unit cell calculations from XRD data for MGB pellets match the odinite-1M data base. Electron microprobe analyses (EMPA) from the average of 31 data points from clay pellets accompanied with Mossbauer analyses were used to calculate the structural formula which is that of odinite: Fe3+0.89 Mg0.45 Al0.67 Fe2+0.30 Ti0.01 Mn0.01) Σ = 2.33 (Si1.77 Al0.23) O5.00 (OH)4.00. QEMSCAN (Quantitative Evaluation of Minerals by Scanning Electron Microscopy) data provided mineral maps of quantitative proportions of the constituent clays. The verdine facies is a clay mineral facies associated with shallow marine shelf and lagoonal environments at tropical latitudes with iron influx from nearby runoff. Its depositional environment is well documented in modern nearshore locations. Recognition of verdine facies clays as the dominant constituent of the MGB clay pellets, rather than glaucony facies clays, allows for a more precise assessment of paleoenvironmental conditions.
Radiation resistance characteristics of graded-index fibers with a core of Ge-, F-doped or B and F-codoped SiO2 glass

The radiation resistance properties of Ge-doped, F-doped and B + F-codoped SiO2 graded-index (GI) fibers have been investigated. The B + F-codoped fiber was found to have excellent radiation resistance properties at 0.85 μm, which enables its practical application in doses exceeding 1 × 106 R. The F-doped fiber had a higher photobleaching effect and a stronger dose rate dependence than the other two fibers. The GeO2-doped fiber showed a minimum radiation-induced loss at 1.3 μm and a low photobleaching effect. An absorption band at 2 eV was induced in the F-doped and B + F-codoped fibers during γ-irradiation.
New quantitative descriptors of amino acids based on multidimensional scaling of a large number of physical–chemical properties

We derive new quantitative descriptors for the 20 naturally occurring amino acids based on multidimensional scaling of 237 physical–chemical properties. We show that a five-dimensional property space can be constructed such that the amino acids are in a similar spatial distribution to that in the original high-dimensional property space. Properties that correlate well with the five major components were hydrophobicity, size, preferences for amino acids to occur in α-helices, number of degenerate triplet codons and the frequency of occurrence of amino acid residues in β-strands. Distances computed for pairs of amino acids in the five-dimensional property space are highly correlated with corresponding scores from similarity matrices derived from sequence and 3D structure comparison. We used the five-dimensional property distances to cluster the amino acids in groups depending on a cutoff distance. These groups define a reduced amino acid alphabet for protein folding studies. Our descriptors should provide a quantitative means to identify property motifs in sequences of protein families. Electronic supplementary material to this paper can be obtained by using the Springer Link server located at http://dx.doi.org/10.1007/s00894-001-0058-5.
Outcome of high-risk neonates with congenital complete heart block paced in the first 24 hours after birth.

Objective Risk factors for poor outcome with congenital complete heart block include prematurity, low birth weight, hydrops, low ventricular rates, and congenital heart disease. In this group, medical therapy is often ineffective, pacing is technically challenging, and mortality exceeds 80%. The purpose of this study is to assess outcomes of patients with congenital complete heart block who were paced in the first 24 hours after birth owing to the presence of known risk factors. Methods We performed a retrospective review of patients with congenital complete heart block paced in the first 24 hours after birth at our institution between November 1, 1995, and July 31, 2007. Results Thirteen patients were identified, 4 of whom had heterotaxy syndrome. Eleven patients had temporary epicardial pacing wires placed; 2 received permanent pacemakers as the initial mode of pacing. There were 7 deaths (54% mortality) at a mean age of 19.9 ± 19 days. Among 7 patients with structural heart disease, there was 1 survivor. Among 6 patients with structurally normal hearts, there were 5 survivors ( P = .025). Patients with temporary wires who survived to permanent pacemaker implantation (6/11) used their temporary leads for 33.8 ± 18.3 days. Conclusions In the severely affected fetus with congenital complete heart block and significant structural heart disease, outcomes remain poor; however, neonates with congenital complete heart block and structurally normal hearts who are monitored antenatally and delivered in a planned fashion at an institution capable of early pacing can have favorable outcomes. The use of temporary pacing wires is an option in the management of these patients.
Causation and Cleanliness: George Callender, Wounds, and the Debates over Listerism

This article reexamines the surgical and historiographic debate over antisepsis and the germ theory through the work of the prominent London surgeon George W. Callender (1830–1879) and the statistical records of St. Bartholomew's Hospital. Surgeons in the mid-nineteenth century faced a rising incidence of wound infection and its systemic complications. Examining mortality and complication rates by type of wound, however, suggests that the extent of this crisis is often overstated. Callender himself occupied a frequently overlooked middle ground in the debate over Listerism. On the one hand, his program of cleanliness, which antedated Lister's work and extended from the wound to the ward, produced excellent and influential results. On the other, while he was never an explicit critic of the germ theory, his writings demonstrate why Lister's collapse of causation into a single etiologic agent was so difficult for surgeons to accept.
Disputes and Arguments Amongst Nomads

Disputes and Arguments Amongst Nomads Robert M. Hayden. Oxford: Oxford University Press, 1999. ix + 1 77 pp., table, references, index.
A comparative approach to closed-loop computation.

Neural computation is inescapably closed-loop: the nervous system processes sensory signals to shape motor output, and motor output consequently shapes sensory input. Technological advances have enabled neuroscientists to close, open, and alter feedback loops in a wide range of experimental preparations. The experimental capability of manipulating the topology—that is, how information can flow between subsystems—provides new opportunities to understand the mechanisms and computations underlying behavior. These experiments encompass a spectrum of approaches from fully open-loop, restrained preparations to the fully closed-loop character of free behavior. Control theory and system identification provide a clear computational framework for relating these experimental approaches. We describe recent progress and new directions for translating experiments at one level in this spectrum to predictions at another level. Operating across this spectrum can reveal new understanding of how low-level neural mechanisms relate to high-level function during closed-loop behavior.
Cytokine disturbances in systemic lupus erythematosus

The pathogenesis of systemic lupus erythematosus (SLE) is complex, and the resulting disease manifestations are heterogeneous. Cytokine dysregulation is pervasive, and their protein and gene expression profiles may serve as markers of disease activity and severity. Importantly, biologic agents that target specific cytokines may represent novel therapies for SLE. Four cytokines (IL-6, TNFα, IFNα, and BLyS) are being evaluated as therapeutic targets in SLE. The present review will examine the roles of each of these cytokines in murine and human SLE, and will summarize results from clinical trials of agents that target these cytokines.
Formation of PbTe nanofilms by electrochemical atomic layer deposition (ALD)

Abstract This article describes optimization of a cycle for the deposition of lead telluride (PbTe) nanofilms using electrochemical atomic layer deposition (ALD). PbTe is of interest for the formation of thermoelectric device structures. Deposits were formed using an ALD cycle on Au substrates, one atomic layer at a time, from separate solutions, containing Pb 2+ or HTeO 2 + ions. Single atomic layers were formed using surface limited reactions, referred to as underpotential deposition (UPD), so the deposition cycle consisted of alternating UPD of Te and Pb. The Pb deposition potential was maintained at −0.35 V throughout the 100 cycle-runs, while the Te deposition potential was ramped up from −0.55 V to −0.40 V over the first 20 cycles and then held constant for the remaining ALD cycles. Coulometry for the reduction of both Te and Pb indicated coverages near one monolayer, each cycle. Electron probe microanalysis (EPMA) indicated a uniform and stoichiometric deposit, with a Te/Pb ratio of 1.01. X-ray diffraction measurement showed that the thin films had the rock salt structure, with a preferential (2 0 0) orientation for the as formed deposits. No annealing was used. Infrared reflection absorption measurements of PbTe films formed with 50, 65, and 100 cycles indicated strong quantum confinement.
Patient symptoms and physician prescribing patterns in the elderly

Abstract The aim was to determine if different doctors prescribed differently for older patients with the same diagnoses as patients who were younger. Five ambulatory-care physicians were selected randomly from a staff of 15. Over age 65 male patients ( N = 329) were compared with 889 younger patients in regard to symptoms and medications. Patient-rated symptoms differed by age of patients but not by the five physicians. Comparison of 20 types of medications showed seven differed by patient age but none by physician. Analysis of data in an age × physician grouping, however, showed that certain physicians treated older patients differently in regard to use of digitalis, tranquilizers and pain medications. The findings suggest remarkable similarity in symptoms for older patients seen by different physicians. While use of the medications did not differ between physicians for patients as a total group, they did differ when age of the patient was taken into account. The inconsistent use of certain medications for the old without support of symptoms and diagnoses raises questions about how the old are viewed as a group by some physicians.
Bulk Polymerization Kinetics by the Adiabatic Reactor Method

Abstract We have shown that the adiabatic reactor method (A.R.M.) is useful to measure bulk polymerization kinetics. The choice of an adequate model is fundamental to represent the kinetics and for use in modeling and processing applications. The definitions of differential and integral errors have been introduced. It has been shown that these definitions lead to different objective functions and minimization problems. With an adequate model, we must be able to find a single set of parameters to minimize both errors simultaneously. We have shown that the n-th order and autocatalytic models are particular cases of a generalized phenomenological model. We continue to study this technique and to develop new forms of estimation. Dynamic models for complex situations which may include heat losses and intermediate species are now under development, and we expect to present them in a forthcoming publication.
Stereoselective Aldehyde Addition to Rhenium-Coordinated Furans

Dihapto-coordinated furan complexes of the form TpRe(CO)(t-BuNC)(2,3-η2-furan) (Tp = hydridotris(pyrazolyl)borate) react with aldehydes in the presence of BF3·OEt2 to yield dihydrofuran complexes. Depending on the reaction conditions, these products take one of three forms: a dihapto-coordinated trans-2-alkyl-3-acyl-2,3-dihydrofuran, trans-2,3-dialkyl-2,3-dihydrofuran, or 4a,7a-dihydro-4H-furo[2,3-d][1,3]dioxine. The first two are formed exclusively as trans-disubstituted products, whereas the last exhibits cis stereochemistry at the ring fusion. These are isolated as mixtures of coordination diastereomers, which are separable by chromatography. Of the two diastereomers of the trans-2-alkyl-3-acyl-2,3-dihydrofuran product obtained in each case, only the major isomer undergoes an interfacial isomerization under ambient conditions. Attempts to decomplex the dihydrofurans were unsuccessful.
Corroboration of the Analysis of an Axially-Directed Antenna Exciting a Conducting Tube

Data to corroborate the analysis presented in a companion paper for an axially-directed antenna exciting a conducting tube are presented. We present a detailed description of the design and construction of the apparatus and of the measurements performed to obtain data. Comparisons of measured and computed driving-point admittance, normalized charge and current on the tube wall, and normalized current and charge on the antenna are presented. It is found that the results from theory and experiment are in excellent agreement.
Nylon 66, Nylon 46, and Pet Phase-Transfer-Catalyzed Alkaline Depolymerization at Atmospheric Pressure

Plastic waste recycling is beneficial because it can lead to a reduction in the amount of waste generated, a decreased need for landfills, and a more rational utilization of resources. An important source of polyethylene terephthalate (PET) for recycling is physically cleaned post-consumer bottles which are ground to form flake, depolymerized, purified, and repolymerized to form recycled resin bottles. Caustic treatment of polyester scrap involves cleavage of the ester linkages. The reaction of aqueous sodium hydroxide (8–10% by weight) with waste material in an autoclave at 210–250°C and elevated pressure goes to completion in about 3–5 hours1. The rate of hydrolysis may be enhanced by the presence of accelerants2,3. Terephthalic acid and ethylene glycol may be recovered from the solution. Hall3 used cetyl trimethylammonium bromide and lauryl dimethylbenzylammonium chloride as accelerants for the caustic reduction of PET.
A blueberry-enriched diet improves renal function and reduces oxidative stress in metabolic syndrome animals: potential mechanism of TLR4-MAPK signaling pathway.

Background Metabolic syndrome (MetS) is characterized by a cluster of health factors that indicate a higher risk for cardio-renal diseases. Recent evidence indicates that antioxidants from berries are alternative to attenuate oxidative stress and inflammation. We tested the hypothesis that inflammation-induced renal damage is triggered by the activation of TLR4, and subsequent modulation of redox-sensitive molecules and mitogen-activated protein kinase (MAPK) pathway.
Autotuning of A PID Controller for an Active Vibration Suppression Device for the Treatment of Essential Tremor

Essential Tremor (ET) is a motion disorder which affects as many as one in 20-25 adults over the age of 40 [1]. Leblanc [2] proposed a device which consists of four linear actuators attached to a patient's wrist in an effort to actively suppress the tremor. This paper demonstrates experimentally a simplified version of that device. The system was tested on a stand designed to simulate an adult lower arm with a tremor in the horizontal plane. A single linear inertial actuator was attached to the "wrist" of the test stand. An accelerometer attached on the opposite side of the arm provided feedback to the controller. This paper demonstrates this system operating to produce 20%-60% vibration reduction in the 6-13 Hz bandwidth.© 2006 ASME
Evaluation of steady and pulsatile flow with dynamic MRI using limited flip angles and gradient refocused echoes.

Magnetic resonance imaging sequences utilizing limited flip angles and gradient echoes yield rapid (less than 2 min) dynamic images of the cardiovascular system. These images contain both accurate anatomical and functional information. Using a gradient refocused acquisition in the steady state (GRASS) in the CINE mode, we studied the relationship between gradient echo signal intensity and velocity of steady and pulsatile flow in a phantom simulating medium to large vessels. Images were acquired on a 1.5 Tesla system (repetition time = 21 ms, echo time = 12 ms, flip angle = 30 degrees). Data from each pulse interval were sorted in 16 images. Signal intensities from flow tube lumina and surrounding stationary water jacket were used to calculate contrast ratios which were compared to velocity measurements made with electromagnetic (EM) flow probes outside the magnet room. During steady flow, signal intensity contrast ratios increased with increasing flow and in a 10 mm thick slice, reached a peak at 48 cm/s, and declined for velocities up to 90 cm/s. Changes in instantaneous velocity during pulsatile flow correlated well (r greater than .88) with signal intensity changes up to a maximum mean velocity of 17 cm/s. Total signal intensity from the lumen for an "R to R" interval correlated extremely well (r greater than .97) with mean pulsatile flow velocities up to 30 cm/s. The excellent correlation between gradient echo signal intensity and actual flow velocities suggests that this imaging sequence might be useful for evaluating normal and pathologic flow phenomena.
Parallel distributed algorithm for texture boundary localization

In most instances the boundaries between textured regions are defined by the gray level contrasts which result from the local interaction between the texture elements in each region. In such cases, the boundaries can be accurately characterized by gray level edge segments. Using these edge segments to localize the texture boundary directly addresses the major problem associated with texture segmentation, namely the localization verses classification accuracy conflict. The accuracy of segmentation methods which rely only on spatially distributed properties to characterize the texture, is limited to the spacial extent of the property used. In contrast, gray level edges are significantly more localized. However, before they can be of any use, the gray level edge segments defining the texture boundary must be isolated from the edges defining the texture elements. In this paper, we define a set of properties to do this. We also incorporate these properties into a parallel distributed algorithm which is used to segment a set of sample texture images.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Airborne digital holographic system for cloud particle measurements.

An in-line holographic system for in situ detection of atmospheric cloud particles [Holographic Detector for Clouds (HOLODEC)] has been developed and flown on the National Center for Atmospheric Research C-130 research aircraft. Clear holograms are obtained in daylight conditions at typical aircraft speeds of 100 m s-1. The instrument is fully digital and is interfaced to a control and data-acquisition system in the aircraft via optical fiber. It is operable at temperatures of less than -30 °C and at typical cloud humidities. Preliminary data from the experiment show its utility for studies of the three-dimensional spatial distribution of cloud particles and ice crystal shapes.
Outcomes of percutaneous endoscopic gastrostomy tube placement using a T-fastener gastropexy device in head and neck and esophageal cancer patients.

Background: Percutaneous endoscopic gastrostomy (PEG) tube placement by the pull technique in head, neck, and esophageal cancer patients has a high complication rate, particularly in infections, and a small risk of tumor implantation. The T-fastener gastropexy technique uses a transabdominal approach to place the PEG device. Objectives: The objective of this study was to review the clinical outcomes and complications related to endoscopic PEG placement with the T-fastener gastropexy technique in patients with head, neck, and esophageal cancers. Methods: This study was a retrospective review of all patients with head, neck, and esophageal cancers with PEG placement from January 1998 to June 2008. Clinical data including patient’s age, gender, type and stage of cancer, date of PEG placement and removal, and reason for PEG removal was recorded. Results: The study group consisted of a total of 356 patients of which 244 were male and 112 were female with a mean age of 63.3 years. There were 276 patients with h...