cssi/SciSciGPT-SciSciNet huggingface dataset:
Parallel Magnetic Resonance Imaging Acquisition and Reconstruction: Application to Functional and Spectroscopic Imaging in Human Brain

Magnetic resonance imaging (MRI) has contributed significantly to modern cancer diagnosis and treatment planning because of its noninvasive nature, versatile image contrast, and high spatiotemporal resolution. For decades, the quest for higher sensitivity and greater spatial and/or temporal resolution has been approached by means of increasing major field strengths, enhancing gradient performance, and improving radio frequency (RF) technology. In this chapter, we present recent MRI advances that use an RF coil array to achieve “­parallel” data acquisition for higher spatiotemporal resolution.
An immunohistochemical signature comprising PTEN, MYC, and Ki67 predicts progression in prostate cancer patients receiving adjuvant docetaxel after prostatectomy.

BACKGROUND: Loss of the tumor suppressor PTEN is common in prostate cancer and may have prognostic significance. The authors examined PTEN and additional protein markers in primary tumors from patients with high-risk, localized prostate cancer who received adjuvant docetaxel in a prospective multicenter trial (TAX2501). METHODS: Fifty-six of 77 patients enrolled in TAX2501 had primary prostatectomy specimens available for immunohistochemical analysis of PTEN, MYC, ERG, tumor protein p53 (p53), antigen KI-67 (Ki67), and phosphorylated forms of Akt, mammalian target of rapamycin (mTOR), and S6 ribosomal protein. Protocol-defined progression included a prostate-specific antigen (PSA) level ≥0.4 ng/mL, radiologic/clinical recurrence, or death. Univariate and multivariable proportional hazards regression analyses were used to investigate the influence of PTEN status (and other protein markers) on progression-free survival (PFS). RESULTS: In this exploratory, post hoc analysis, PTEN protein loss (vs presence) was observed in 61% of patients and was associated with lower preoperative PSA levels, higher clinical stage, lower Ki67 expression, the presence of p53, and the presence of ERG. In univariate analysis, the factors associated with PFS included Gleason sum, seminal vesicle invasion, PTEN status, MYC expression, and Ki67 expression. In multivariable analysis, only 3 variables emerged as independent prognostic factors for PFS: PTEN status (P = .035), MYC expression (P = .001), and Ki67 expression (P < .001). A prognostic model was constructed that incorporated clinical covariates as well as information on PTEN, MYC, and Ki67. CONCLUSIONS: The current results indicated that PTEN status, MYC expression, and Ki67 expression in primary tumor samples may predict PFS more accurately than clinical factors alone in men with high-risk prostate cancer who receive adjuvant docetaxel after prostatectomy. If validated, these hypothesis-generating findings may have prognostic and therapeutic implications and may aid clinical trial design. Cancer 2012. © 2012 American Cancer Society.
Leading at the top: Understanding women's challenges above the glass ceiling

Abstract Women leaders contribute positively to organizations yet remain significantly underrepresented in corporate leadership positions. While the challenges women face are well-documented, less understood are the factors that shape the experience and success of women who, against significant odds, rise above the glass ceiling. This paper advances scholarship on women and leadership by analyzing the conditions under which women are promoted to top leadership positions and exploring the opportunities and challenges they face post-promotion. We draw on two data sources: comparison of the career trajectories of all women who have ever served as CEO in the Fortune 500 with a matched sample of men CEOs as well as in-depth interviews with women executives across a variety of sectors. Our analysis reveals that women are more likely than men to be promoted to high risk leadership positions and often lack the support or authority to accomplish their strategic goals. As a result, women leaders often experience shorter tenures compared to male peers. We consider the implication of our findings for theory, research and practice.
Airport surface operations display applications of DO-272 vector airport data

In 2001, industry standardization of initial requirements for high accuracy airport map databases was completed, resulting in the release of EUROCAE/RTCA standards document DO-272. Later that year, the FAA began making available vector airport map databases compliant with the new RTCA standard. The high accuracy and content of this data, combined with airport surface traffic surveillance information, will enable a new level of flight deck situational awareness applications. Rockwell Collins is investigating the use of these technologies on a variety of avionics display application platforms.
Relative acute toxicities of hydrogen fluoride, hydrogen chloride, and hydrogen bromide in nose- and pseudo-mouth-breathing rats

Hydrogen fluoride (HF), hydrogen bromide (HBr), and hydrogen chloride (HCl) gases can be generated during the pyrolysis of a variety of materials and they may be encountered in numerous industrial settings. Although injury to the respiratory tract has been characterized following the inhalation of halide gases via the nasal route, essentially no experimental information is currently available about their injurious effects when they are inhaled during mouth breathing. In this study, we simulated mouth breathing by using a pseudo-mouth-breathing (MB) rat model in order to: (1) characterize the profiles and magnitudes of respiratory tract injury that result from the acute inhalation of relatively high mass concentrations of the above halides when the upper airway is bypassed, and (2) assess the relative toxicities of HF, HBr, and HCl when inhaled by way of either the nasal or the oral pathways. Tracheal tubes connected to mouthpieces were inserted into temporarily anesthetized rats, i.e., mouth breathers. Awake rats were placed into whole body flow plethysmographs for pulmonary ventilation studies while they were exposed either to air or to 1300 ppm of HF, HBr, or HCl for 30 min. Similarly pretreated rats were also exposed but without the mouthpiece, i.e., nose breathers (NB). The animals were euthanized 24 hr after exposure for histopathologic analyses of their upper and lower respiratory tracts and for lung gravimetric measurements. Tissue injury following NB exposure to the halides was confined to the nasal region, e.g., epithelial and submucosal necrosis, accumulations of inflammatory cells, exudates, and the extravasation of erythrocytes. MB exposure caused higher mortality rates and major tissue disruption in the trachea, including epithelial, submucosal, glandular, and cartilage necrosis, and accumulations of inflammatory cells and exudates. More peripheral lung damage was manifested by lung gravimetric increases and histopathologic changes primarily in the larger conducting airways. The results of this study demonstrate that the injurious response profiles to HF, HBr, and HCl markedly differ as a function of the route by which they are inhaled. Furthermore, examinations of the magnitudes of injury caused by exposure to the halides during nose or mouth breathing in conjunction with animal ventilatory data obtained during exposure to the halides suggest that HF, HBr, and HCl are quantitatively similar in their toxic effects in the respiratory tract.
Oligovalent Amyloid-Binding Agents Reduce SEVI-Mediated Enhancement of HIV-1 Infection

This paper evaluates the use of oligovalent amyloid-binding molecules as potential agents that can reduce the enhancement of human immunodeficiency virus-1 (HIV-1) infection in cells by semen-deriv...
Invasive gastric candidiasis.

A case of invasive gastric candidiasis is reported. The frequency and importance ofCandida sp. as a gastric pathogen is reviewed.
Reversal of multidrug resistance by two nordihydroguaiaretic acid derivatives, M4N and maltose-M3N, and their use in combination with doxorubicin or paclitaxel.

Purpose: Multidrug resistance (MDR) continues to be a major obstacle for successful anticancer therapy. One of the principal factors implicated in MDR is the over expression of P-glycoprotein (Pgp), the product of the MDR1 gene. Methods: Here we explore the possibility of using the transcription inhibitor tetra-O-methyl nordihydroguaiaretic acid (M4N) to inhibit Sp1-regulated MDR1 gene expression and restore doxorubicin and paclitaxel sensitivity to multidrug resistant human cancer cells in vitro and in vivo. Results: We found that M4N acted synergistically with doxorubicin and paclitaxel in inhibiting the growth of the cells in culture allowing significant dose reductions of both drugs. We observed no such synergism when M4N was used in combination with cisplatin, another chemotherapeutic agent, but not a Pgp substrate, as analyzed by the combination index and isobologram methods. Analysis of MDR1 mRNA and Pgp levels revealed that at sublethal doses, M4N inhibited MDR1 gene expression in the multidrug resistant NCI/ADR-RES cells and reversed the MDR phenotype as measured by Rhodamine-123 retention. In addition, M4N was found to inhibit doxorubicin-induced MDR1 gene expression in drug sensitive MCF-7 breast cancer cells. Conclusions: M4N and maltose-tri-O-methyl nordihydroguaiaretic acid (maltose-M3N), a water-soluble derivative of NDGA, were also able to reverse the MDR phenotype of the tumor cells in a xenograft model system and combination therapy with M4N or maltose-M3N and paclitaxel was effective at inhibiting growth of these tumors in nude mice.
Differential metal content and gene expression in rat left ventricular hypertrophy due to hypertension and hyperactivity.

Abstract The spontaneously hypertensive rat (SHR) has been studied extensively as a model of left ventricular hypertrophy (LVH) and associated cardiac dysfunction due to hypertension (HT). The SHR also possesses a hyperactive trait (HA). Crossbreeding SHR with Wistar–Kyoto (WKY) control rats, which are nonHT and nonHA, followed by selected inbreeding produced two additional homozygous strains: WKHT and WKHA, in which the traits of HT and HA, respectively, are expressed separately. WKHT, WKHA and SHR all display LVH, but only the SHR exhibits cardiac dysfunction. We hypothesized that cardiac dysfunction in the SHR is uniquely characterized by calcium overload. We measured total cardiac Ca, Cu, Fe, K, Mg and Zn in the four strains. We found elevated Ca and depressed Cu, Mg and Zn with HT, but not unique to SHR. We surmise that HT promotes aberrant regulation of cardiac Ca2+, Cu2+, Mg2+ and Zn2+, which does not necessarily result in cardiac dysfunction. Interestingly, Cu was elevated in HA strains compared to nonHA counterparts. We then analyzed gene expression as mRNA of Cu-containing proteins, most notably mitochondrial-Cox, Dbh, Lox, Loxl1, Loxl2, Sod1 and Tyr. The gene expression profiles of Lox, Loxl1, Loxl2 and Sod1 were found especially high in the WKHA, which if reflective of protein content could account for the high Cu content in the WKHA. The mRNA of other genes, notably Mb, Fxyd1, Maoa and Maob were also examined. We found that Maoa gene expression and monoamine oxidase-A (MAO-A) protein content were low in the SHR compared to the other strains. The finding that MAO-A protein is low in the SHR and normal in the WKHT and WKHA strains is most consistent with the idea that MAO-A protects against the development of cardiac dysfunction in LVH but not against LVH in these rats.
The cost-effectiveness of CT-guided sacroiliac joint injections: A measure of QALY gained

Objective: The purpose of this study is to estimate the total cost and the quality of life years (QALY) gained for computer tomography (CT)-guided sacroiliac joint (SIJ) injections. The cost per QALY gained for the procedure is the primary end-point of this study. Methods: In our 1-year prospective institutional study, we gathered 30 patients undergoing CT-guided SIJ injections for degenerative changes at the SIJ space. Patient-reported outcomes included both the US population-based EQ-5D (EuroQol) index score and the EQ-visual analog scale (VAS). The EQ-5D is based on mobility, self-care, usual activities, pain/discomfort, and anxiety depression. Utility expenditures were based on hospital charges at our institution. Results: All 30 patients had one pre-injection physician visit followed by 43 initial injections (13 bilateral). Each patient underwent one CT scan, and three patients required additional plain films. In the 1 year following the injections, 26 physician visits were documented. Five patients ...
Preoperative intra-articular morphine and bupivacaine for pain control after outpatient arthroscopic anterior cruciate ligament reconstruction.

Background and Objectives. The purpose of this study was to determine whether intra-articular injection of bupivacaine, morphine, or a combination prior to surgery provided pain control after arthroscopic anterior cruciate ligament (ACL) reconstruction. Methods. These data were collected as a two-stage prospective, randomized, blinded observer study. All patients received a standard general anesthetic, which included an intra-articular injection 20 minutes prior to incision. In phase I, three solutions were assigned randomly in a 60-mL volume. Group 1 was saline, group 2 was 0.25% bupivacaine, and group 3 was 0.25% bupivacaine with 1 mg morphine sulfate (MS). Phase II was identical to phase I in technique and had four groups. Group 1 was 0.25% bupivacaine, group 2 was 1 mg MS in saline, group 3 was 0.25% bupivacaine with 1 mg MS, and group 4 was 0.25% bupivacaine with 3 mg MS. All groups in phases I and II contained 1:200,000 epinephrine, freshly added. Pain scores were evaluated at 0, 30, 60, 90, 120, and 240 minutes postoperative using a visual analog scale. For pain scores of 5 or greater, 50 μg fentanyl was administered at 5-minute intervals until pain was controlled. After transition from phase I to phase II of the postanesthesia care unit (PACU), hydrocodone/acetaminophen tablets were used. Results. Thirty patients were entered into phase I of the study. Both treatment groups (2 and 3) had significant (P < .05) pain reduction on arrival to the PACU. Group 3 had significantly (P < .05) reduced need for fentanyl during the PACU stay. Forty-nine patients entered phase II of the study. In phase II, group 3 had the lowest pain scores on arrival to the PACU. At 120 and 240 minutes, pain scores were lower in groups 3 and 4. Fentanyl and hydrocodone uses were significantly lower during the PACU stay in groups 3 and 4. Conclusions. Presurgical injection of a solution of 0.25% bupivacaine, morphine, and epinephrine provided pain control and decreased opioid use in the PACU. Increasing the morphine dose did not improve the clinical result.
Body-wearable beam steering antenna array for 5.2 GHz WLAN applications

This paper presents the study and design of a 5.2 GHz WLAN body-wearable electronically steerable parasitic antenna radiator (ESPAR) array. A collinear array of four driven dipoles and eight parasitic dipoles is formed to attain beam steering in the azimuth plane and a narrow beam in the elevation plane. The collinear ESPAR array provides beam steering in three directions while allowing 12.8 dBi of peak gain at 5.2 GHz. PIN diode switches are used to control the beam of the array.
E(s2)-Optimal supersaturated designs with good minimax properties

Abstract An improved E ( s 2 ) lower bound is derived for two-level supersaturated designs. This improved bound is used to prove E ( s 2 ) -optimality of the best designs obtained via algorithmic search in all cases with N = 10 , 12, 14, and 16 runs (except the N = 14 run, m = 16 factor case). New exchange algorithms which generalize the NOA algorithm of Nguyen [1996. An algorithmic approach to constructing supersaturated designs. Technometrics 38, 69–73] and which tend to find E ( s 2 ) -optimal designs with better minimax properties are proposed. Row swapping algorithms are used to find E ( s 2 ) -optimal designs when the number of factors is large. E ( s 2 ) -optimal designs found via algorithmic search are compared to cyclicly constructed E ( s 2 ) -optimal designs using the minimax criterion.
Opalescent nuclear cataract

Thirty-eight patients with excellent visual acuity but poor visual function as measured by contrast sensitivity and glare testing were studied. Clinical characteristics of opalescent nuclear cataracts, which have previously been described biochemically, are reported. The findings indicate that opalescent nuclear sclerosis is responsible for increased lenticular myopia and increased glare disability. This form of cataract responds rapidly to low power phacoemulsification of short duration, allowing a satisfactory surgical result.
Generic Revision in the Holarctic Ground Squirrel Genus Spermophilus

The substantial body of research on Holarctic ground squirrels amassed over the past century documents considerable variability in morphological, cytogenetic, ecological, and behavioral attributes in the genus Spermophilus F. Cuvier, 1825. Recent molecular phylogenetic studies suggest that the traditionally recognized genera Marmota Blumenbach, 1779 (marmots), Cynomys Rafinesque, 1817 (prairie dogs), and Ammospermophilus Merriam, 1892 (antelope ground squirrels) render Spermophilus paraphyletic, potentially suggesting that multiple generic-level lineages should be credited within Spermophilus. Herein, we recognize 8 genera formerly subsumed in Spermophilus, each of which is morphologically diagnosable, craniometrically distinctive, and recovered as a monophyletic clade in phylogenetic analyses utilizing the mitochondrial gene cytochrome b. Generic-level names are available for each of these ground squirrel assemblages, most of which are exclusively or predominantly North American in distribution (Notocitellus A. H. Howell, 1938; Otospermophilus Brandt, 1844; Callospermophilus Merriam, 1897; Ictidomys J. A. Allen, 1877; Poliocitellus A. H. Howell, 1938; Xerospermophilus Merriam, 1892; and Urocitellus Obolenskij, 1927). Only Spermophilus sensu stricto is restricted to Eurasia. Generic subdivision of Spermophilus more aptly illuminates the taxonomic relationships, ecomorphological disparity, and biogeographic history of Holarctic ground squirrels.
Control of diffusion induced dislocations in phosphorus diffused silicon

Abstract Control of surface diffusant density is shown to limit phosphorus diffusion induced dislocations in silicon. By minimizing the diffusant density, it is possible to eliminate electrically inactive phosphorus in addition to the diffusion induced dislocations, while also achieving impurity profiles which closely approximate the error function complement. Correlations are made between the type of diffused impurity profile, the inactive phosphorus content and the number of diffusion induced dislocations. The impurity level at which dislocations begin to appear is also discussed.
ENDOR Characterization of a Synthetic Diiron Hydrazido Complex as a Model for Nitrogenase Intermediates

Molybdenum-dependent nitrogenase binds and reduces N2 at the [Fe7, Mo, S9, X, homocitrate] iron-molybdenum cofactor (FeMo-co). Kinetic and spectroscopic studies of nitrogenase variants indicate that a single Fe−S face is the most likely binding site. Recently, substantial progress has been made in determining the structures of nitrogenase intermediates formed during alkyne and N2 reduction through use of ENDOR spectroscopy. However, constraints derived from ENDOR studies of biomimetic complexes with known structure would powerfully contribute in turning experimentally derived ENDOR parameters into structures for species bound to FeMo-co during N2 reduction. The first report of a paramagnetic Fe−S compound that binds reduced forms of N2 involved Fe complexes stabilized by a bulky β-diketiminate ligand (Vela, J.; Stoian, S.; Flaschenriem, C. J.; Munck, E.; Holland, P. L. J. Am. Chem. Soc. 2004, 126, 4522−4523). Treatment of a sulfidodiiron(II) complex with phenylhydrazine gave an isolable mixed-valence FeII...
The Impact of Unemployment on Congressional Elections 1958-1974 A Cross-Sectional Analysis

Bivariate tabulations uncover relationships between the high rates of change in and high rates of unemployment and the percentage of states experiencing gains in the U.S. House Democratic percentag...
Uptake of arachidonic acid into membrane phospholipids: effect on chloride transport across cornea

We demonstrate that arachidonic acid (AA) stimulation of chloride transport across frog cornea is mediated via two independent pathways: (1) stimulation of prostaglandins and cAMP synthesis, and (2) a direct physical change in the membrane produced by substitution of different phospholipid acyl chains. AA is well known as a precursor in the synthesis of prostaglandins, which have been shown to stimulate cAMP synthesis and chloride transport in frog cornea. We show that frog cornea can convert exogenous AA to PGE2, but that in the presence of 10(-5) M indomethacin both the conversion to PGE2 and stimulation of cAMP are completely blocked. However, with indomethacin the action of AA to stimulate chloride transport (as measured by SCC) remains, but peak height of the response is reduced to 57% of that found when AA alone is given. Similarly, we show that propranolol completely blocks cAMP stimulation, but stimulation of SCC is reduced to 45% of the original response. Therefore, cAMP appears to be responsible for roughly half of the observed stimulation in SCC. By gas chromatographic analysis we show that significant quantities of AA can rapidly substitute into membrane phospholipids of corneal epithelium and L929 cells following the addition of AA to the medium. Modification of membrane phospholipid structure can affect membrane viscosity, membrane-bound enzyme activity, and the distribution and lateral mobility of integral proteins. It seems likely that such alterations in the properties of the membrane may modulate the rate of chloride transport, and this may constitute the second mechanism. Upon addition of AA, both mechanisms appear to stimulate chloride transport simultaneously, and are apparently additive. We show that prolonged exposure to AA results in a large incorporation of AA into phospholipid and consequently, a perturbation in the ratio of unsaturated to saturated fatty acids. We also find evidence of a compensatory cellular mechanism that alters the ratio of endogenously synthesized fatty acids and tends to reduce the membrane-perturbing effect of AA.U
Age-associated tyrosine nitration of rat skeletal muscle glycogen phosphorylase b : characterization by HPLC-nanoelectrospray-Tandem mass spectrometry

Abstract We identified age-dependent post-translational modifications of skeletal muscle glycogen phosphorylase b (Ph-b), isolated from F1 hybrids of Fisher 344×Brown Norway rats. Ph-b isolated from 34 months old rats showed a statistically significant decrease in specific activity compared to 6 months old animals: 13.8±0.7 vs. 20.6±0.8 Umg −1 protein, respectively. Western blot analysis of the purified Ph-b with anti-3-NT antibodies revealed an age-dependent accumulation of 3-nitrotyrosine (3-NT), quantified by reverse-phase HPLC–UV analysis to increase from 0.05±0.03 to 0.34±0.11 (mol 3-NT/mol Ph-b) for 6 vs. 34 months old rats, respectively. HPLC–nanoelectrospray ionization—tandem mass spectrometry revealed the accumulation of 3-NT on Tyr 113 , Tyr 161 and Tyr 573 . While nitration of Tyr 113 was detected for both young and old rats, 3-NT at positions 161 and 573 was identified only for Ph-b isolated from 34 months old rats. The sequence of the rat muscle Ph-b was corrected based on our protein sequence mapping and a custom rat PHS2 sequence containing 17 differently located amino acid residues was used instead of the database sequence. The in vitro reaction of peroxynitrite with Ph-b resulted in the nitration of multiple Tyr residues at positions 51, 52, 113, 155, 185, 203, 262, 280, 404, 473, 731, and 732. Thus, the in vitro nitration conditions only mimic the nitration of a single Tyr residue observed in vivo suggesting alternative pathways controlling the accumulation of 3-NT in vivo. Our data show a correlation of age-dependent 3-NT accumulation with Ph-b inactivation.
Intracellular sodium activity and sodium transport inNecturus gallbladder epithelium

Ion-sensitive glass microelectrodes, conventional microelectrodes and isotope flux measurements were employed inNecturus gallbladder epithelium to study intracellular sodium activity, [Na]i, electrical parameters of epithelial cells, and properties of active sodium transport. Mean control values were: [Na]i: 9.2 to 12.1mm; transepithelial potential difference,Ψms: −1.5 mV (lumen negative); basolateral cell membrane potential,Ψes: −62 mV (cell interior negative); sodium conductance of the luminal cell membrane,gNa: 12 μmho cm−2; active transcellular sodium flux, 88 to 101 pmol cm−2 sec−1 (estimated as instantaneous short-circuit current). Replacement of luminal Na by K led to a decrease of the intracellular sodium activity at a rate commensurate to the rate of active sodium extrusion across the basolateral cell membrane. Mucosal application of amphotericin B resulted in an increase of the luminal membrane conductance, a rise of intracellular sodium activity, and an increase of short-circuit current and unidirectional mucosa to serosa sodium flux. Conclusions: (i) sodium transport across the basolateral membrane can proceed against a steeper chemical potential difference at a higher rate than encountered under control conditions; (ii) the luminal Na-conductance is too low to accommodate sodium influx at the rate of active basolateral sodium extrusion, suggesting involvement of an electrically silent luminal transport mechanism; (iii) sodium entry across the luminal membrane is the rate-limiting step of transcellular sodium transport and active sodium extrusion across the basolateral cell membrane is not saturated under control conditions.
Time-domain system for assessing variation in heart rate.

The paper presents an alternative to Fourier techniques for assessment of heart rate variation. The system operates on R-R interval data (intervals between successive R-waves of an ECG). Artefacts are first detected and corrected by recombination of deviant intervals. Next, the highest frequency variation is recognised by identifying changes in the sign of the slope of successive R-R intervals as ‘peaks’ and ‘troughs’. Lower frequency variation is determined from the variation in higher frequency peaks. The period of variation is computed as the sum of the intervals between two peaks, and extent of variation is represented by the peak-to-trough difference. Variation in a given frequency range is then quantified as the median extent of all variation within that range. Assessment of variation at the respiratory frequency by the peak/trough method is highly correlated with results derived from spectral techniques, while the two methods show consistently weaker correlations in the assessment of lower-frequency variation. Peak/trough assessment of three types of variation is consistently better correlated with heart rate than are analogous spectral measurements. Results suggest that the method described here may be preferable to spectral techniques for analysis of heart rate variation that is dependent on base heart rate.
Hepatic pulmonary fusion in an infant with a right-sided congenital diaphragmatic hernia and contralateral mediastinal shift

Hepatic pulmonary fusion is extremely rare with only 9 previous cases reported in the literature. In typical cases, the clinician should be alerted to the possibility of hepatic pulmonary fusion if the chest radiograph shows a large opacity on the right side without a contralateral mediastinal shift. The authors present a case of right-sided diaphragmatic hernia and hepatic pulmonary fusion with associated contralateral mediastinal shift discovered beyond the neonatal period. The 9 previous cases were retrospectively reviewed with special attention to mediastinal shift on preoperative chest radiograph, operative procedure, and mortality. Only one previous case demonstrated a contralateral mediastinal shift. The most common procedure performed was partial separation of the hepatic pulmonary fusion and approximation of the diaphragmatic defect. Four of the previous 9 patients died. In our case, reduction of bowel and approximation of the diaphragmatic defect around the fused liver and lung have been successful.
Utilization management in the clinical laboratory: An introduction and overview of the literature

There is a broad literature addressing the need for improving utilization management in medical care. Numerous review articles and case studies have described approaches to utilization management challenges in the laboratory. This article will present an overview of the literature on laboratory utilization management and will compile a "toolbox" of strategies that can be used to address specific utilization management initiatives. A clear theme among successful utilization management programs is the need to recruit institutional champions both for the overall utilization management program and for ad hoc assistance with specific utilization challenges. It is important that these individuals represent a cross section of laboratory and clinical specialties and that the group be organized as a committee that has been established by the administrative and physician leadership of the organization. The changing nature of healthcare reimbursement will likely provide increased motivation to control laboratory testing and costs. Clinical pathologists are in a unique position to observe testing behavior patterns, suggest alternatives, implement order entry changes, manage testing algorithms and provide interpretive services for laboratory testing. For these reasons, clinical pathologists have a major opportunity to become institutional leaders in utilization management.
Functional Neural Development from Human Embryonic Stem Cells: Accelerated Synaptic Activity via Astrocyte Coculture

How a naive human neuroepithelial cell becomes an electrophysiologically active neuron remains unknown. Here, we describe the early physiological development of neurons differentiating from naive human embryonic stem (hES) cells. We found that differentiating neuronal cells progressively decrease their resting membrane potential, gain characteristic Na+ and K+ currents, and fire mature action potentials by 7 weeks of differentiation. This is similar to the maturation pattern observed in animals, albeit on a greatly expanded time scale. An additional 3 weeks of differentiation resulted in neurons that could fire repetitive trains of action potentials in response to depolarizing current pulses. The onset of spontaneous synaptic activity also occurred after 7 weeks of differentiation, in association with the differentiation of astrocytes within the culture. Cocultures of hES cell-derived neuroepithelial cells with exogenous astrocytes significantly accelerated the onset of synaptic currents but did not alter action potential generation. These findings suggest that the development of membrane characteristics and action potentials depend on the intrinsic maturation of Na+ and K+ currents, whereas synaptic transmission is enhanced by astrocytes, which may be achieved independently of the maturation of action potentials. Furthermore, we found that although astrocyte-conditioned medium accelerated synaptic protein localization, it did not increase synaptic activity, suggesting a contact-dependant mechanism by which astrocytes augment synaptic activity. These results lay the foundation for future studies examining the functional development of human neurons and provide support for the potential application of human cells in restorative neuronal therapies.
Impact of interconception antibiotics on the endometrial microbial flora

Objective The purpose of this study was to evaluate the impact of an interconception antibiotic regimen on endometrial microbial flora and histologic type. Study design This was a secondary analysis of a double-blind randomized placebo-controlled trial of prophylactic metronidazole plus azithromycin that was given to 241 women (antibiotics, 118 women; placebo, 123 women) with a previous preterm delivery to prevent recurrent preterm delivery. Endometrial cultures and histologic types were obtained at randomization and 2 weeks after treatment. The prevalence of either the new acquisition or the resolution of individual microbes, categories of microbes, and plasma cell endometritis were compared by chi-square or Fishers' exact tests. Results Overall, antibiotics were associated with lower acquisition and higher resolution of microbes. Of women without Gardnerella at baseline, 14% of the women who received antibiotics vs 34% of the women who received placebo had positive endometrial culture for the organism after treatment ( P G vaginalis at baseline, 57% of the women who received antibiotics vs 33% of the women who received placebo ( P Conclusion The antibiotic regimen prevented the acquisition and promoted the resolution, but not the eradication, of gram-negative rods such as G vaginalis and the aerobic subcategory.
Metabolic formation of nucleoside-modified analogues of S-adenosylmethionine.

Abstract Evidence is presented for the metabolism of six different adenosine analogues (formycin, 7-deazaadenosine, 8-azaadenosine, 2-fluoroadenosine, purine ribonucleoside and 3′-deoxyadenosine) to their corresponding S-nucleosidylmethionine derivatives in human erythrocytes and mouse lymphocytes. The identification of these novel metabolites was based upon chromatographic and enzymatic characterization of the unique radioactive substance found in cells incubated with each of these adenosine analogues plus L-[methyl-3H]methionine. The metabolic formation of analogues of S-adenosylmethionine may contribute to the inhibition of cellular methylation reactions caused by various purine analogues.
Mechanism of anode break stimulation in the heart

Anodal stimulation is routinely observed in cardiac tissue, but only recently has a mechanism been proposed. The bidomain cardiac tissue model proposes that virtual cathodes induced at sites distant from the electrode initiate the depolarization. In contrast, none of the existing cardiac action potential models (Luo-Rudy phase I and II, or Oxsoft) predict anodal stimulation at the single-cell level. To determine whether anodal stimulation has a cellular basis, we measured membrane potential and membrane current in mammalian ventricular myocytes by using whole-cell patch clamp. Anode break responses can be readily elicited in single ventricular cells. The basis of this anodal stimulation in single cells is recruitment of the hyperpolarization-activated inward current I(f). The threshold of activation for I(f) is -80 mV in rat cells and -120 mV in guinea pig or canine cells. Persistent I(f) "tail" current upon release of the hyperpolarization drives the transmembrane potential toward the threshold of sodium channels, initiating an action potential. Time-dependent block of the inward rectifier, I(K1), at hyperpolarized potentials decreases membrane conductance and thereby potentiates the ability of I(f) to depolarize the cell on the break of an anodal pulse. Inclusion of I(f), as well as the block and unblock kinetics of I(K1), in the existing Luo-Rudy action potential model faithfully reproduces anode break stimulation. Thus active cellular properties suffice to explain anode break stimulation in cardiac tissue.
Capturing oscillator injection locking via nonlinear phase-domain macromodels

Injection locking is a nonlinear dynamical phenomenon that is often exploited in electronic and optical oscillator design. Behavioral modeling techniques for oscillators that predict this phenomenon accurately are of significant scientific and practical importance. In this paper, we propose a nonlinear approach for generating small phase-domain oscillator/voltage-controlled oscillator (VCO) macromodels that capture injection locking well. Our nonlinear phase-domain macromodels are closely related to recent oscillator phase noise and jitter theories, and can be extracted efficiently by algorithm from SPICE-level descriptions of any oscillator or VCO. Using LC and ring oscillators as test cases, we confirm the ability of nonlinear phase macromodels to capture injection locking, and also obtain significant computational speedups over full SPICE-level circuit simulation. Furthermore, we show that our approach is equally effective for capturing the dynamics of transition to locking, including unlocked tones and phase jump phenomena.
Implications of the changes in maintenance of certification for endocrinologists.

It is easy to be cynical about maintenance of certification (MOC). Very few other countries have recertification requirements of their doctors; in the United States, other professionals such as lawyers and accountants are not required to take summative tests to retain their certification. Most clinicians are already actively engaged in continuing medical education (CME) (1). The certification process is widely regarded as frustrating, time-consuming, and expensive (2–4). There has been little proof of benefit, and compliance is increasingly mandated rather than being chosen as an honorific (5). The coming months are likely to raise additional questions about the value proposition of MOC because the requirements for American Board of Internal Medicine (ABIM) board certification are changing again, with new content requirements, additional assessment expectations, and likely a higher price tag. These additional changes will leavemanyendocrinologists looking for clarificationanddeciding whether participation is likely to be worth it.
Synthesis and characterization of a poly (methyl methacrylate-acrylic acid) copolymer for bioimplant applications

This paper describes the development of a new crosslinked poly(methyl methacrylate-acrylic acid) copolymer for potential applications in bone implants. This copolymer, comprising hydrophobic and hydrophilic components, has been designed to provide small amounts of controllable swelling strains at saturation when exposed to an aqueous saline environment. The volume fraction of the hydrophobic methyl methacrylate monomer to the hydrophilic acrylic acid monomer strongly influenced the swelling behavior of the copolymer. Two different cross-linking agents, allyl methacrylate and diethylene glycol dimethacrylate, were evaluated for their effectiveness in cross-linking and limiting the saturated swelling levels. The influences of the amounts of cross-linking agents and other processing parameters on the swelling behavior of the copolymer were studied using differential scanning calorimetry measurements, solubility tests, and swelling measurements in saline solutions. These measurements provided a good understanding of the structure of the copolymer, the effectiveness of the cross-linkers, the swelling mechanisms in this system, and the factors that strongly affect the swelling weight gain levels in this copolymer. © 1997 John Wiley & Sons, Inc.
Effects of superatmospheric oxygen on strawberry fruit quality and decay

The effects of elevated O2 alone or in combination with elevated CO2 atmospheres for postharvest decay control on strawberry fruit (Fragaria×ananassa Duch.) were assessed. In vitro and in vivo growth of Botrytis cinerea Pers.:Fr. and the effects on fruit quality were determined under eight atmospheres: air, 40, 60, 80, 90 and 100 kPa O2, 40 kPa O2+15 kPa CO2 and air+15 kPa CO2. The commercially-used CO2 level of 15 kPa in air and its combination with 40 kPa O2 were most effective in suppressing mycelial growth in vitro following 7 days at 5°C under the atmospheres. However, after 14 days of treatment at 5°C, 100 kPa O2 inhibited mycelial growth more than either of the CO2 treatments. In all treatments, the growth rate increased immediately upon removal from the atmosphere, indicating that there was no residual inhibitory effect. The 100 kPa O2 treatment was also the most effective in controlling decay on the fruit during 14 days of storage. Although the quality parameters of respiration, ethylene production, firmness, soluble solids, titratable acidity and external color were only mildly affected by the superatmospheric O2 treatments, volatile content (acetaldehyde, ethanol and ethyl acetate) increased greatly. While the fruit treated with 15 kPa CO2 had the highest volatile concentrations after 14 days at 5°C, after an additional 2 days in air at 20°C, volatile concentrations in fruit treated with 100 kPa O2 equaled or surpassed those of fruit treated with CO2. The volatile concentration in fruit treated with 15 kPa CO2 generally decreased during 2 days in air, while the volatile content increased in fruit treated with high O2, with greater increases with increasing O2 level. The fruit treated with 40 kPa O2+15 kPa CO2 achieved an intermediate level between the O2 and CO2 treatments. Although the 100 kPa O2 treatment reduced decay, both in vitro and in vivo, increased production of fermentative metabolites that impart a negative organoleptic property to the fruit makes this a doubtful alternative for decay control on strawberry.
Enzymic oxidation of epinephrine with formation of an actomyosin adenosine triphosphatase inhibitor.

Abstract An epinephrine-oxidizing enzyme from bovine uterine muscle has been further purified and characterized. Adrenochrome is an intermediate in the oxidation of epinephrine by this enzyme. Adrenochrome also activates the enzyme, resulting in an autocatalytic oxidation of epinephrine. Another product of this reaction, which has been isolated and tentatively identified as a zwitterion isomer of adrenochrome, strongly inhibits actomyosin ATPase.
Tensioned metastable fluids and nanoscale interactions with external stimuli—Theoretical-cum-experimental assessments and nuclear engineering applications

Abstract The field of tensioned (sub-zero pressure) metastability of organic and inorganic fluids and their responses to external stimuli is under study at Purdue University. Unique properties related to energy storage and sub-nano scale response to external stimuli have been found that give rise to the capability for causing localized supercritical states leading to fluid boiling by visible light photons and other fundamental particles over eight orders of magnitude in the energy range (i.e., from the sub −eV to MeV range). A theoretical model is developed for predicting limits of tension metastability and validated against experimental data. Resonant acoustics and centrifugal force-based systems are described for attaining as-desired tension metastable states along with triggering mechanisms for nano-to-macroscale energy storage-cum-release. Finite-element modeling and simulation framework for design of such systems with experimental benchmarking are described. Technological impacts on diverse fields such as nuclear material detection, physics-based spectroscopy, monitoring of power levels in nuclear systems, general cavitation physics of fluids, acoustically driven thermonuclear fusion, and super compression states attainment are discussed.
Serial CS presentation and shuttlebox avoidance conditioning: A further look at the tendency to delay responding

Two experiments were reported. The first compared the effects of nonserial and serial (e.g., S1 followed by S2) CS presentations, while the second study compared nonserial and serial compound (e.g., S1 followed by S1 and S2) CS presentations on the acquisition of rats’ avoidance responses in a shuttlebox situation. The avoidance-response latencies of Ss presented the serial CS conditions tended to be delayed until after the onset of the last stimulus segment introduced into the sequence. This was not the case for the nonserial Ss who tended to avoid shortly after the onset of the CS-US interval. The delay in responding noted for the serial CS Ss occurred when either two or three stimuli comprised the sequence and when either serial or serial compound presentation was employed. Serial compound conditions increased avoidance responding, but the serial condition did not. Other effects of CS complexity on avoidance responding were also reported.
Pancreatic endocrine function in cystic fibrosis

To characterize pancreatic endocrine secretion and to examine interrelationships among alterations in alpha, beta, and pancreatic polypeptide cell function in patients with cystic fibrosis (CF), we studied 19 patients with exocrine insufficiency (EXO), including 9 receiving insulin therapy (EXO-IT); 10 patients with no exocrine insufficiency (NEXO); and 10 normal control subjects. First-phase C-peptide response to intravenously administered glucose was significantly impaired in CF patients with exocrine insufficiency (EXO-IT = 0.02 +/- 0.01; EXO = 0.11 +/- 0.02; NEXO = 0.25 +/- 0.05; control subjects = 0.30 +/- 0.04 nmol/L). Lowering fasting glucose levels with exogenous insulin administration in EXO-IT did not improve beta cell responsivity to glucose. The C-peptide response to arginine was less impaired (EXO-IT = 0.12 +/- 0.02; EXO = 0.15 +/- 0.02; NEXO = 0.23 +/- 0.06; control subjects = 0.28 +/- 0.04 nmol/L). Alpha cell function, measured as peak glucagon secretion in response to hypoglycemia, was diminished in EXO but not NEXO (EXO-IT = 21 +/- 10; EXO = 62 +/- 19; NEXO = 123 +/- 29; control subjects = 109 +/- 12 ng/L). Despite diminished glucagon response, EXO patients recovered normally from hypoglycemia. Peak pancreatic polypeptide response to hypoglycemia distinguished CF patients with exocrine insufficiency from those without exocrine insufficiency (EXO-IT = 3 +/- 2; EXO = 3 +/- 1; NEXO = 226 +/- 68; control subjects = 273 +/- 100 pmol/L). Thus CF patients with exocrine disease have less alpha, beta, and pancreatic polypeptide cell function than CF patients without exocrine disease. These data suggest either that exocrine disease causes endocrine dysfunction in CF or that a common pathogenic process simultaneously and independently impairs exocrine and endocrine function.
Plasma rest frame frequencies and polarizations of the low-frequency upstream waves: ISEE 1 and 2 Observations

The plasma rest frame frequencies and polarizations of the large amplitude low frequency (0.03 Hz) upstream waves are investigated using magnetic field data from the dual ISEE 1 and 2 spacecraft. The monochromatic sinusoidal waves associated with intermediate ion fluxes are propagating in both the Alfven and magnetosonic modes, in both cases with typical frequencies approximately 0.1 times the local proton gyrofrequency and wavelengths of approximately 1 R(E). It is shown that the generation of the magnetosonic mode can be explained by the cyclotron resonance mechanism driven by narrow reflected ion beams, but the concurrent observation of Alfven mode waves appears to require wave generation by the more isotropic diffuse ion distributions as well.