cssi/SciSciGPT-SciSciNet huggingface dataset:
Can exercise electrocardiography and thallium-201 myocardial imaging exclude the diagnosis of coronary artery disease? Bayesian analysis of the clinical limits of exclusion and indications for coronary angiography.

Abstract The objective of this study was to determine whether exercise electrocardiography can be combined with thallium-201 myocardial imaging and the clinical history to exclude the diagnosis of coronary artery disease. All 96 patients in this study were referred for coronary angiography because of chest pain but did not have prior myocardial infarction; 52 percent had coronary artery disease. Each patient's chest pain was classified as either typical or not typical of angina pectoris. Negative tests with inadequate exercise stress (less than 85 percent of the age-predicted maximal heart rate) and combined tests with discordant results (either exercise electrocardiography or thallium imaging positive and the other test negative) were judged nondiagnostic. Nondiagnostic tests that contributed most to the uncertainty of results were classified separately: exercise electrocardiogram, 35 patients; thallium imaging, 9 patients; and combined exercise electrocardiogram and thallium imaging, 50 patients. The ability of each test to rule out coronary artery disease was defined by its predictive error (probability of coronary disease despite a negative test): history of chest pain not typical of angina, 26 percent (11 of 42); exercise electrocardiogram, 22 percent (5 of 23); thallium imaging, 27 percent (6 of 35); and negative findings on both exercise electrocardiogram and thallium imaging, 6 percent (1 of 17). Finally, when only the patients with atypical chest pain were considered, there was zero (0 of 15) predictive error if both tests were negative. Negative exercise electrocardiography and thallium imaging during adequate stress ruled out any coronary artery disease in these patients with considerable reliability (94 percent) and excluded multivessel disease with even greater reliability. These exclusion tests for coronary artery disease were most reliable in patients in whom the clinical diagnosis of coronary artery disease was least likely, as defined by Bayes' theorem. It is concluded that there is no perfect noninvasive test to exclude coronary disease in all patient populations; however, coronary angiography is not necessary to rule out the diagnosis of coronary artery disease in patients who'have (1) no clinical indicators of a very high probability of coronary disease, such as typical angina, (2) adequate exercise stress, (3) negative exercise electrocardiogram and (4) negative exercise thallium images.
Mothering While Illegal: Undocumented Mothers from Senegal in the United States

Scholarship on immigrant women is slowly integrating motherhood as a distinct category of analysis. While this emerging body of research offers invaluable insights about immigrant women’s adjustments to mothering across cultures, no study has yet addressed the important parameter of legal status. This oversight results in an epistemological invisibility of undocumented alien mothers, yet a significantly large section of the immigrant population. If mothering in a situation of immigration presents challenges that test and eventually showcase the creativity, resilience, and resourcefulness of immigrant women, how does legal status add to these challenges? What are the particular challenges faced by undocumented mothers? How do these challenges impact their self-perceptions as mothers, their social identities, and ultimately their mothering practices? Our presentation seeks preliminary responses to these unattended questions by analyzing the life-stories of undocumented Senegalese mothers in the United States.The stories shared and analyzed in our presentation have been gathered over 5 years, through sustained interaction and interviews with these women. In addressing the set of questions raised above, the objective of our presentation is threefold. First we seek to highlight the unpublicized challenges faced by this important yet overlooked segment of West African immigrant women. Second, we have a theoretical endeavor to translate the contradictory and multifarious location of these mothers in both a Senegalese habitus where motherhood is an important social identity and a situation of illegality that entails social invisibility. Finally and most importantly, we showcase how African women continuously create ways to raise above challenges through their creativity and resourcefulness.
Patterns of Obesogenic Neighborhood Features and Adolescent Weight: A comparison of statistical approaches

BACKGROUND: Few studies have addressed the potential influence of neighborhood characteristics on adolescent obesity risk, and findings have been inconsistent. PURPOSE: Identify patterns among neighborhood food, physical activity, street/transportation, and socioeconomic characteristics and examine their associations with adolescent weight status using three statistical approaches. METHODS: Anthropometric measures were taken on 2682 adolescents (53% female, mean age=14.5 years) from 20 Minneapolis/St. Paul MN schools in 2009-2010. Neighborhood environmental variables were measured using GIS data and by survey. Gender-stratified regressions related to BMI z-scores and obesity to (1) separate neighborhood variables; (2) composites formed using factor analysis; and (3) clusters identified using spatial latent class analysis in 2012. RESULTS: Regressions on separate neighborhood variables found a low percentage of parks/recreation, and low perceived safety were associated with higher BMI z-scores in boys and girls. Factor analysis found five factors: away-from-home food and recreation accessibility, community disadvantage, green space, retail/transit density, and supermarket accessibility. The first two factors were associated with BMI z-score in girls but not in boys. Spatial latent class analysis identified six clusters with complex combinations of both positive and negative environmental influences. In boys, the cluster with highest obesity (29.8%) included low SES, parks/recreation, and safety; high restaurant and convenience store density; and nearby access to gyms, supermarkets, and many transit stops. CONCLUSIONS: The mix of neighborhood-level barriers and facilitators of weight-related health behaviors leads to difficulties disentangling their associations with adolescent obesity; however, statistical approaches including factor and latent class analysis may provide useful means for addressing this complexity. Language: en
The Possibility of Gain Among the 5d-4f Transitions of the Rare Earth Ions

We discuss 5d-4f transitions in the rare earth ions. Specifically, we have studied various hosts doped with divalent europium and with trivalent praseodemium.
Air Compressor Battery Duration With Mechanical Ventilation in a Field Anesthesia Machine

ABSTRACT Compressed air to power field anesthesia machine ventilators may be supplied by air compressor with battery backup. This study determined the battery duration when the compPAC ventilator's air compressor was powered by NiCd battery to ventilate the Vent Aid Training Test Lung modeling high (HC = 0.100 L/cm H2O) and low (LC = 0.020 L/cm H2O) pulmonary compliance. Target tidal volumes (VT) were 500, 750, and 1,000 mL. Respiratory rate = 10 bpm, inspiratory-to-expiratory time ratio = 1:2, and fresh gas flow = 1 L/min air. N = 5 in each group. Control limits were determined from the first 150 minutes of battery power for each run and lower control limit = mean VT − 3SD. Battery depletion occurred when VT was below the lower control limit. Battery duration ranged from 185.8 (±3.2) minutes in the LC-1000 group to 233.3 (±3.6) minutes in the HC-750 group. Battery duration of the LC-1000 group was less than all others (p = 0.027). The differences among the non-LC-1000 groups were not clinically significant.
One probe, two-channel imaging of nuclear and cytosolic compartments with orange and red emissive dyes

Several new DNA-targeting probes that exhibit binding-induced 'turn on' fluorescence are presented. Two of the dyes, orange emissive 1, (E)-4-(4(-4-methylpiperazin-1-yl)phenyl)6-(4-(4-methylpi-perazin-1-yl)styryl)pyrimidin-2-ol), and red emissive 2, (E)-4-(4(-4-methyl-piperazin-1-yl)-phenyl)6-(4-(4-methylpiperazin-1-yl)styryl)-1,3-propanedionato-κO,κO']difluoroborane), are brightly fluorescent when bound to DNA, but are virtually non-fluorescent in aqueous solutions. Confocal fluorescence microscopy of live BT474, MCF7 and HEK293 cells demonstrates that both probes are cell permeable and rapidly accumulated intracellularly into cell nuclei and the cytosol. Taking advantage of their environmental sensitivity, these two pools of fluorophores are readily resolved into separate channels, and thus, a single dye allows two-color imaging of the nuclear and cytosolic compartments.
The integration of geophysical and enhanced Moderate Resolution Imaging Spectroradiometer Normalized Difference Vegetation Index data into a rule-based, piecewise regression-tree model to estimate cheatgrass beginning of spring growth

Cheatgrass exhibits spatial and temporal phenological variability across the Great Basin as described by ecological models formed using remote sensing and other spatial data-sets. We developed a rule-based, piecewise regression-tree model trained on 99 points that used three data-sets – latitude, elevation, and start of season time based on remote sensing input data – to estimate cheatgrass beginning of spring growth (BOSG) in the northern Great Basin. The model was then applied to map the location and timing of cheatgrass spring growth for the entire area. The model was strong (R2 = 0.85) and predicted an average cheatgrass BOSG across the study area of 29 March–4 April. Of early cheatgrass BOSG areas, 65% occurred at elevations below 1452 m. The highest proportion of cheatgrass BOSG occurred between mid-April and late May. Predicted cheatgrass BOSG in this study matched well with previous Great Basin cheatgrass green-up studies.
High-intensity laser-induced vaporization and explosion of solid material

Material removal from the front surface of a solid by a high-intensity laser beam is analytically treated. The model used allows for transmission of laser energy past the front surface and for transient phenomena. It is found that for certain laser and material parameters subsurface temperatures will exceed the surface temperature. Under such conditions, explosive removal of material could occur resulting in very rapid and efficient material removal. These predictions are compared to previously published experimental results.
Evidence Suggesting That Galanin (GAL), Melanin-Concentrating Hormone (MCH), Neurotensin (NT), Proopiomelanocortin (POMC) and Neuropeptide Y (NPY) Are Targets of Leptin Signaling in the Hypothalamus

Leptin (OB protein) reduces food intake by acting at the hypothalamic level. The purpose of the present study was to identify potential targets of leptin signaling in the hypothalamus in ad-lib fed rats. Central administration of leptin (5 microg) for 3 days decreased food intake and body weight gain in association with a decrease in hypothalamic galanin (GAL), melanin-concentrating hormone (MCH), proopiomelanocortin (POMC) and neuropeptide Y (NPY) gene expression and with an increase in neurotensin (NT) gene expression. In pair-fed rats, NPY gene expression was increased and there was no change in either MCH, GAL, POMC or NT gene expression. This study identifies GAL, MCH, POMC and NT as non-NPY targets of leptin signaling and suggests that leptin's action on food intake and body weight is most likely mediated by inhibiting excitatory (e.g. NPY, MCH, GAL, POMC) and stimulating inhibitory (e.g., NT) signals in the feeding circuitry.
German cockroach extract increases bronchial epithelial cell interleukin‐8 expression

Summary Background Cockroach exposure has been recognized as a common trigger for asthma. While dust mite and Aspergillus fumigatus aeroallergens have been noted to have direct effects on airway epithelium, direct effects of cockroach proteins have not been determined. Objective The purpose of this study was to investigate whether cockroach extract has a direct pro-inflammatory effect on airway epithelium. Methods We examined the effect of crude German cockroach (Blattella germanica) extract on IL-8 expression in a human bronchial epithelial cell line (16HBE14o-cells) and primary human bronchial epithelial cells. Transcription from the IL-8 promoter and protein abundance were determined by reporter assay and enzyme-linked immunosorbent assay (ELISA), respectively. Endotoxin levels in the crude cockroach extracts were determined using the Limulus Amebocyte Lysate assay. Protease activity was assessed using Azocoll as a substrate. Results We found that crude cockroach extract induced a synergistic increase in TNF-α-induced transcription from the IL-8 promoter. The synergistic effect was observed with as little as 0.3 µg/mL of crude cockroach extract, while larger concentrations (30 µg/mL) approximately doubled TNF-α-induced IL-8 promoter activity. Similar effects of cockroach extract on IL-8 protein abundance were observed in both 16HBE14o- and primary human bronchial epithelial cells. Addition of endotoxin at concentrations found in the cockroach extract had no effect on TNF-α-mediated IL-8 expression. The serine protease inhibitors aprotinin and phenylmethylsulphonyl fluoride abolished cockroach-induced synergy, while the cysteine protease inhibitors E64 and leupeptin had little effect. Measurement of protease activity using Azocoll as a substrate confirmed the presence of protease activity in cockroach extracts. Addition of recombinant Bla g 2, Bla g 3 and Bla g 5 had no effect on TNF-α-induced IL-8 promoter activation. Finally, cockroach extract also increased TNF-α-induced transcription from the IL-6 promoter. Conclusions German cockroach extract contains novel serine protease activity which has a direct pro-inflammatory effect on airway epithelial cells
Rheotaxis of Young Arctic Grayling from Populations That Spawn in Inlet or Outlet Streams of a Lake

Abstract Rheotactic behavior of young Arctic grayling Thymallus arcticus from two populations that spawn in inlet or outlet streams of a lake and from reciprocal crosses between the two populations was tested in an artificial stream at flow velocities up to 7 cm/s. Fertilized eggs from wild fish and the resulting young from the two populations were incubated and reared under identical conditions in a hatchery before being tested. Young fish from both populations (referred to as inlet and outlet young) were tested at the time of initial swim-up and at 11–41 d after swimup. Outlet young had a significantly greater tendency to swim upstream than inlet young at temperatures of 10 (newly emerged but not older young), 12, and 16°C under both full (10.1–15.6 μmol·s−1·m−2) and dim (0.03–0.05 μmol·s−1·m−2) light conditions. Young from reciprocal crosses had intermediate responses at 12 and 16°C. However, both outlet and inlet young had similar, very weak, upstream responses when tested in darkness or (except for n...
SU‐E‐I‐167: Impact of Peak SUV Definition on Quantification of Treatment Response

Purpose: PET‐based treatment response assessment typically measures the change in SUVmax, which is adversely affected by noise. SUVpeak has been recommended as a more robust alternative, but currently its associated region‐of‐interest (ROIpeak) is not uniquely defined. We investigated the impact of different ROIpeak definitions on quantification of SUVpeak and tumor response. Methods: Seventeen patients with solid malignancies were treated with an anti‐proliferative, molecular targeted agent. Using the cellularproliferation marker [F‐18]FLT, whole‐body PET/CT scans were acquired at baseline and during treatment. Lesions with highest FLT uptake (∼2/patient) were segmented on PETimages and tumor response was assessed via the relative change in SUVpeak. For each tumor, 24 different SUVpeak and response values were determined by changing ROIpeak shape, size, and location. Within each tumor, variation of the 24 values was measured using range, coefficient of variation (CV) for SUVpeak, and standard deviation (SD) for response. For each ROIpeak definition, population average SUVpeak and response were determined over all tumors. Results: Substantial variation in both SUVpeak and response resulted from changing the ROIpeak definition. Intra‐tumor SUVpeak variation (CV: 17%) and response variation (SD: 9%) ranged as far as 50% from the mean. Population average SUVpeak variation (CV: 14%) ranged as far as 30% from the mean but population average tumor response variation (SD: 2%) ranged only 3% from the mean. Size of ROIpeak caused more variation in SUVpeak and response than location or shape of ROIpeak. Conclusion: Quantification of individual tumor response using SUVpeak is highly sensitive to ROIpeak definition, which can significantly impact the use of SUVpeak for treatment response assessment. However, population average response is robust to ROIpeak definition. Standardization of SUVpeak is crucial for consistent assessment of treatment response. Clinical trials are necessary to compare the efficacy of SUVpeak and SUVmax for quantification of response to therapy.
Rigidity of symplectic Anosov diffeomorphisms on low dimensional tori

We show that any symplectic Anosov diffeomorphism of a four torus T4 with sufficiently smooth stable and unstable foliations is smoothly conjugate to a linear hyperbolic automorphism of T4.
Frequency and significance of left ventricular thickening in transplanted hearts in children.

The pediatric myocardium has been shown to thicken markedly during steroid administration for the treatment of pulmonary or neurologic disease. Yet, in the pediatric heart transplant patient, left ventricular (LV) thickening is sometimes used as a marker for rejection without accounting for steroid immunosuppression. The aim of this study was to determine timing and correlates of changes in LV thickness in pediatric cardiac transplant patients. In 11 patients (11 days old to 16 years old), LV thickness (mass) was first measured during the entire post-transplant course. Second, thickness was measured before and during rejection. Last, to separate the independent effects of rejection and steroids on LV mass, echocardiograms were reviewed in the immediate post-transplant period, when our protocol prescribes aromatic changes in steroid closes and rejection episodes were rare. Specifically, the donor heart underwent 5 evaluations: at donation, at peak steroid dose, 5 days after peak steroid dose, at moderate steroid dose, and at very low maintenance dose. LV mass changed most dramatically and consistently during the first 20 to 40 days after transplant. Thereafter, mass had little consistent changes and did not change significantly during any of the 52 rejection episodes. Mass increased 5 days after peak steroid dose (54 ± 30 to 74 ± 38 g/ht2.7, p < 0.05) and decreased during low maintenance levels of steroids. Thickening was associated with cumulative steroid dose (r = 0.66, p = 0.03) and age (r = − 0.62, p = 0.04). Thus, in pediatric heart transplant patients, as in other pediatric diseases, LV thickening is associated with steroid administration. Thickening may be an unreliable marker for acute cellular rejection.
Data hard with a vengeance (invited talk)

Action flicks and the analysis of software data in industry have more in common than you think. Both action heroes and development teams are on tight deadlines to save the day. Getting wrong information can lead to disastrous outcomes. In this talk, I will share experiences from my six years of research in the Empirical Software Engineering Group working with engineers towards sound data-driven decision about software.
Exploring Trust Propagation Behaviors in Online Communities

Trust plays a very important role in people's real lives. As online social networking becomes more and more popular nowadays, it is urgent to use trust in online communities, like Amazon.com, Epinions.com, Facebook, Twitter and so on. Unfortunately, trust links in online communities are sparse compared with the number of pairs of users. To address this problem, computer scientists are now using trust propagation to infer trust links using existing information. However, users show different behavior patterns in different online communities. There are two classic theories in sociology, balance theory and status theory, aiming to cope with this problem. In this paper, we use our trust management systems to analyze these two social theories in two real datasets: Epinions.com and Twitter.
Scientific Change as Political Action Franz Boas and the Anthropology of Race

A theory is value-neutral when no constitutive values are part of its content. Nonneutral theories seem to lack objectivity because it is not clear how the constitutive values could be empirically confirmed. This article analyzes Franz Boas’s famous arguments against nineteenth-century evolutionary anthropology and racial theory. While he recognized that talk of “higher civilizations” encoded a constitutive, political value with consequences for slavery and colonialism, he argued against it on empirical and methodological grounds. Boas’s arguments thus provide a model of how, under the right conditions, scientific inquiry can provide empirically objective grounds for political critique.
Delayed radiation necrosis of brainstem related to fast neutron beam irradiation: case report and literature review.

A 42-year-old man developed necrosis of the brainstem 10 months following fast neutron irradiation of a recurrent adenocystic carcinoma of the right submandibular salivary gland. The neoplasm had been diagnosed 15 years earlier. Neck dissection and several local excisions failed to control local extension, so that 7000 rad 4.8 MeV x-rays were administered. The right mandible and part of the tongue and palate were resected for recurrence and chemotherapy and transfer factor were given. Because of cranial neuropathy and erosion of the skull base, fast neutron radiation (2.080 rads) was administered five and one-half years after the x-ray therapy, but to a nonoverlapping field. Ten months later, rapidly progressive symptoms and signs of multiple cranial nerve palsies on the right side and left hemihypesthesia and hemiplegia appeared. Clinical manifestations of brainstem necrosis lasted 4 months. Postmortem examination demonstrated radionecrosis of pons and upper medulla, predominantly on the right side. This case illustrates the efficacy of neutron radiation in eradicating local carcinoma and also the serious complications of this therapeutic modality. Cancer 44:473-479, 1979.
Transdermal menopausal hormone therapy: delivery through skin changes the rules.

Importance to the field: Transdermal hormone therapy is replacing oral estrogens and androgens as safe enhancements of life quality for postmenopausal women. Estradiol and testosterone are dosed into the microvascular circulation directly through skin so there is no first-pass hepatic transformation or deactivation of the dosed estradiol or testosterone.Areas covered in this review: This review critically examines recent clinical trials describing experience with transdermal estradiol and testosterone in postmenopausal women. Transdermal estradiol is effective in the treatment of vasomotor symptoms (VMS) and can provide its benefits at higher levels of safety than have been heretofore possible with oral estrogens. Transdermal testosterone is effective in the treatment of hypoactive sexual desire disorder (HSDD) documented in multiple, well-powered randomized clinical trials with demonstrated high levels of safety.What the reader will gain: The reader will learn that transdermal estradiol and testosterone,...
Effect of Schooling on Categorization Preferences: A Picture-Classification Study

The effects of schooling on the categorization preferences in a picture-classification task were studied in a sample of 332 Salvadoran children, between the ages of 6 and 14 yr. Schooling was the major cause of the developmental shift from a perceptually-based to a conceptually-based categorization preference. Children from higher grades were significantly less likely than their less-schooled counterparts to use perceptible categories and more likely to use functional, nominal, and superordinate categories. Urban-dwelling affected the development in the use of nominal, but not functional, categories. The results are discussed in relation to the findings of previous research.
Adsorbate band dispersions for C on Ru(0001)

Abstract We have studied carbon-induced two-dimensional energy bands on Ru(0001) using angle-resolved photoelectron spectroscopy and have compared them with ab initio calculations. We find a nearly parabolic band (bottom at E F - 9.8eV at k ∥ = 0, effective mass ∼ 1.5 m e ) which we assign to the C 2p z valence states of a graphitic carbon overlayer. Compared to graphite, these states are bound more tightly by 2.3 eV.
Uncertainty resulting from inconstancy in the slope of the log plot of homologous series

The free energy of partition of a methylene group\(\Delta G_{CH_2 }^ \circ \) is constant within a homologous series down to C5 and nearly constant to C3, contrary to the finding of Golovnya and Grigoryeva [5]. Retention indices are linear with carbon number: values may be extrapolated from higher carbon numbers to C5 within experimental uncertainty, to C4 with error no greater than 5 units and to C3 with error no greater than 10 units. Error in extrapolating the logarithm of the adjusted retention time, log t′R, to C5 is thus negligible, to C4 has possible error up to 5b/100 and to C3 up to 10b/100, whereb is the slope of the plot of log t′R against carbon number.
Effects of prolactin on the kidney of a teleostean fish: Transmission electron microscopic observations

Abstract Mammalian prolactin (PRL) was previously found to be toxic to the dwarf gourami, Colisa lalia . In an effort to identify the cause of the PRL toxicity, kidneys of fish treated with the hormone were examined by transmission electron microscopy. At the ultrastructural level many degenerating cells, characterized by nuclear fragmentation, cytoplasmic dissolution, and pyknosis, were seen in the renal tubules. A variety of profiles of crystalline bodies were present in the interstitial tissue. Neither crystalline bodies nor degenerating cells were seen in kidneys from control animals. These findings provide a clear indication that the kidney is at least one of the primary sites of the PRL toxic effect.
Crocodyliform Feeding Traces on Juvenile Ornithischian Dinosaurs from the Upper Cretaceous (Campanian) Kaiparowits Formation, Utah

Crocodyliforms serve as important taphonomic agents, accumulating and modifying vertebrate remains. Previous discussions of Mesozoic crocodyliform feeding in terrestrial and riverine ecosystems have often focused on larger taxa and their interactions with equally large dinosaurian prey. However, recent evidence suggests that the impact of smaller crocodyliforms on their environments should not be discounted. Here we present direct evidence of feeding by a small crocodyliform on juvenile specimens of a ‘hypsilophodontid’ dinosaur from the Upper Cretaceous (Campanian) Kaiparowits Formation of southern Utah. Diagnostic crocodyliform bite marks present on a left scapula and a right femur, as well as a partial probable crocodyliform tooth crown (ovoid in cross-section) preserved within a puncture on the right femur, comprise the bulk of the feeding evidence. Computed tomography scans of the femoral puncture reveal impact damage to the surrounding bone and that the distal tip of the embedded tooth was missing prior to the biting event. This is only the second reported incidence of a fossil crocodyliform tooth being found embedded directly into prey bone. These bite marks provide insight into the trophic interactions of the ecosystem preserved in the Kaiparowits Formation. The high diversity of crocodyliforms within this formation may have led to accentuated niche partitioning, which seems to have included juvenile dinosaurian prey.
Temporary closure of the abdominal wall by use of silicone rubber sheets after operative repair of ruptured abdominal aortic aneurysms

Management of patients after operative repair of abdominal aortic aneurysms can be further complicated if primary closure of the abdominal wall cannot be technically accomplished or is associated with profound increases in intraabdominal and peak inspiratory pressures. We recently treated five patients with ruptured abdominal aortic aneurysms and one patient with a ruptured thoracoabdominal aneurysm whose abdominal incisions had to be closed with a Dacron reinforced, silicone sheet. All patients were hemodynamically unstable either at admission to the hospital or became so during operation. Four patients required the insertion of a silicone rubber sheet at the primary operation because of massive retroperitoneal hematoma or edema of the bowel wall or both. Incisions in two patients were closed primarily, but the patients required reexploration and secondary closure with silicone rubber sheets because of the development of marked increases in peak inspiratory pressures, intraabdominal pressures, and decreased urinary output. Four of the six patients subsequently underwent successful removal of the silicone rubber sheets with delayed primary closure of the abdominal wall, and two others died before removal. The patient with the ruptured thoracoabdominal aneurysm died on postoperative day 20 because of pulmonary sepsis but had a healed abdominal incision. The three surviving patients have been discharged. A silicone rubber sheet may be necessary for closure of the abdominal wall after repair of ruptured abdominal aortic aneurysm in patients where primary abdominal wall closure is impossible or where it results in compromise in respiratory or renal function.
Overview of the Development of the Fluoropolymer Industry

The present review briefly describes the development of the fluoropolymer industry in the past 70 years. Discussed are industrial fluoropolymers including polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidenefluoride, polyvinylfluoride, ETFE, ECTFE, FEP, PFA, THV, Teflon AF and Cytop. Nafion is included as a special functional fluoropolymer material. These industrial fluoropolymers are introduced in the order of their discovery or time of first production, included are their chemical structures, thermal properties, mechanical properties, electrical and electronic properties, optical properties, chemical resistance, oxidative stabilities, weather stabilities, processabilities and their general applications. The main manufacturing companies for the different types of fluoropolymer products are also mentioned.
"A Whole Other Story": The Electronic Narrative of Illness

Faith McLellan studies a cyberspace narrative of illness that grew out of a father's anguish after his son was diagnosed with acute lymphocytic leukemia. The essay discloses ways in which illness narratives on the Internet challenge our conceptions of authorship, readership, and closure. In these narratives, argues McLellan, communication is often spontaneous, yet the text still achieves cohesion despite, or perhaps because of, its multiple and sometimes chaotic voices.
Canonical Quantization of (1+1)-dimensional Gravity

Based on Polyakov's evaluation of the Fadeev-Popov determinant for (1+1)-dimensional gravity in the conformal gauge we formulate a canonical quantization in the synchronous gauge. We find that the system is describable as a quantum mechanical system of one degree of freedom. The quantization can be carried out and solved when any number of gauge fields are included. Scalar and spinor fields lead to new difficulties. For positive cosmological constant the geometry collapses as suggested by the classical system. For negative cosmological constant a more interesting behavior involving exponentially expanding and contracting universes occurs.
Training mode does not affect orthostatic tolerance in chronically exercising subjects

This study tested the hypotheses that trained swimmers would have greater orthostatic tolerance than runners and, if present, it would be due to differences in their autonomic and hemodynamic responses to graded central hypovolemia. Twenty intercollegiate male athletes [11 runners and 9 swimmers; VO2max =70.0 (1.6) vs 69.5 (2.6) ml·kg−1·min−1, respectively] underwent graded lower body negative pressure (LBNP) to presyncope. The swimmers were heavier [80.5 (1.9) vs 70.3 (1.9) kg, P<0.05], with larger resting cardiac [4.44 (0.29) vs 3.68 (0.18) l·min−1·m−2] and total peripheral conductance [0.056 (0.04) vs 0.044 (0.02) units·m−2] indices. Neither spontaneous cardiac baroreflex sensitivity (sequence method) nor heart rate variability (spectral analysis) differed significantly between groups at rest. LBNP tolerance did not differ between groups, with an index value of 51 (2) kPa·min for the runners and 54 (4) kPa·min for the swimmers [383 (16) vs 402 (32) mmHg·min] , although the swimmers had larger declines in pulse pressure and tended (P=0.078) to have larger declines in total peripheral conductance index in the last completed stage of LBNP. These responses did not differ between groups in the last 2 min of LBNP. Neither the heart rate, mean arterial pressure nor forearm vascular conductance responses differed between groups throughout. Changes in heart rate variability indices did not differ significantly between groups, with similar declines in the high frequency component and increases in the low frequency/high frequency ratio. These data suggest that swim training does not lead to greater orthostatic tolerance than run training, and responses to maximal LBNP do not differ between swimmers and runners. Moreover, neither heart rate nor the autonomic modulation of the heart rate response to LBNP are affected by training modality.
Crack opening and closure in fatigue

Experimental and analytical crack opening and closure levels are determined for cracks growing in notched members. Replica techniques and the scanning electron microscope were used in the experiments. The analytical procedure involves the determination of the reversed plastic zone size, the crack opening and closure stresses and is based on Budiansky-Hutchinson's theoretical study of closure. Results indicate consistently that crack opening levels are higher than crack closure levels. Small cracks in bluntly notched members under R = − 1 loading exhibited lower crack opening (closure) levels than longer cracks. However, for R = 0 loading the crack opening (closure) levels remained relatively unchanged with increasing crack length. The implications of crack opening and closure results on the behavior of small cracks are discussed. An ad hoc approach for determining crack closure levels is presented in the Appendix. The suggested method gives good estimates of crack closure levels in the absence of plasticity and short crack effects and may be useful to engineers and designers.
Determination of organophosphorus fire retardants and plasticizers in wastewater samples using MAE-SPME with GC-ICPMS and GC-TOFMS detection

Determination of organophosphorus fire retardants and plasticizers at trace levels in wastewater is described. In this work, microwave assisted extraction (MAE) and solid-phase microextraction (SPME) are used for sample preparation to extract and preconcentrate the analytes, followed by analysis by gas chromatography coupled to inductively coupled plasma mass spectrometry (GC-ICP-MS) for phosphorus-specific detection. Gas chromatography coupled to time of flight mass spectrometry (GC-TOF-MS) was used to confirm the organphosphorus fire retardants in wastewater. The detection limits of organophosphorus fire retardants (OPFRs) were 29 ng L−1 for tri-n-butyl phosphate (TnBP), 45 ng for L−1 for tris(2-butoxyethyl)phosphate (TBEP), and 50 ng L−1 for tris(2-ethylhexyl)phosphate (TEHP). Optimized extraction conditions were performed at 65 °C for 30 min and with 10% NaCl. Application of MAE during the sample preparation prior to the SPME allowed the detection of tris(2-ethylhexyl) phosphate, which has been difficult to determine in previous work. Application of the method to wastewater samples resulted in detecting 3.1 μg L−1 P from TnBP, 5.0 μg L−1 P from TBEP, and 4.0 μg L−1 P from TEHP. The presence of these compounds were also confirmed by SPME-GC-TOF-MS.
A synthesis of experimental research in stage fright

(1959). A synthesis of experimental research in stage fright. Quarterly Journal of Speech: Vol. 45, No. 2, pp. 134-145.
Radiosensitization of Human Cervical Cancer Cells by Inhibiting Ribonucleotide Reductase: Enhanced Radiation Response at Low-Dose Rates

Purpose To test whether pharmacologic inhibition of ribonucleotide reductase (RNR) by 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP, NSC #663249) enhances radiation sensitivity during low-dose-rate ionizing radiation provided by a novel purpose-built iridium-192 cell irradiator. Methods and Materials The cells were exposed to low-dose-rate radiation (11, 23, 37, 67 cGy/h) using a custom-fabricated cell irradiator or to high-dose-rate radiation (330 cGy/min) using a conventional cell irradiator. The radiation sensitivity of human cervical (CaSki, C33-a) cancer cells with or without RNR inhibition by 3-AP was evaluated using a clonogenic survival and an RNR activity assay. Alteration in the cell cycle distribution was monitored using flow cytometry. Results Increasing radiation sensitivity of both CaSki and C33-a cells was observed with the incremental increase in radiation dose rates. 3-AP treatment led to enhanced radiation sensitivity in both cell lines, eliminating differences in cell cytotoxicity from the radiation dose rate. RNR blockade by 3-AP during low-dose-rate irradiation was associated with low RNR activity and extended G 1 -phase cell cycle arrest. Conclusions We conclude that RNR inhibition by 3-AP impedes DNA damage repair mechanisms that rely on deoxyribonucleotide production and thereby increases radiation sensitivity of human cervical cancers to low-dose-rate radiation.
Simulating chaotic behavior with finite-state machines

The iterates of the logistic map, ${x}_{n+1}$=${\mathrm{rx}}_{n}$(1-${x}_{n}$), exhibit chaotic behavior for many values of r\ensuremath{\in}[3.57,4.0]. However, if we treat x as an m-state discrete variable, as is done in any digital computer calculation, then the iterates of x invariably form short limit cycles of length \ensuremath{\approxeq} \ensuremath{\surd}m for chaotic values of r. Although this result questions the validity of digital computer simulations of chaos, we nevertheless find that the statistical properties of the continuous equation, such as the invariant probability distribution and the Lyapunov exponent, are preserved in these cycles. We also find that the transition between periodic and chaotic behavior is still well defined in the discretized map.
1,25-Dihydroxyvitamin D3 induces monocytic differentiation of human myeloid leukemia cells by regulating C/EBPβ expression through MEF2C

Myogenic enhancer factor2 (Mef2) consists of a family of transcription factors involved in morphogenesis of skeletal, cardiac and smooth muscle cells. Among the four isoforms (Mef2A, 2B, 2C, and 2D), Mef2C was also found to play important roles in hematopoiesis. At myeloid progenitor level, Mef2C expression favors monocytic differentiation. Previous studies from our laboratory demonstrated that ERK5 was activated in 1,25-dihydroxyvitamin D3 (1,25D)-induced monocytic differentiation in AML cells and ERK5 activation was accompanied by increased Mef2C phosphorylation. We therefore examined the role of Mef2C in 1,25D-induced monocytic differentiation in AML cell lines (HL60, U937 and THP1) and found that knockdown of Mef2C with small interfering RNA (siRNA) significantly decreases the expression of the monocytic marker, CD14, without affecting the expression of the general myeloid marker, CD11b. CCAAT/enhancer-binding protein (C/EBP) β, which can bind to CD14 promoter and increase its transcription, has been shown to be the downstream effector of 1,25D-induced monocytic differentiation in AML cells. When Mef2C was knocked down, expression of C/EBPβ was reduced at both mRNA and protein levels. The protein expression levels of cell cycle regulators, p27(Kip1) and cyclin D1, were not affected by Mef2C knockdown, nor the monopoiesis related transcription factor, ATF2 (activating transcription factor 2). Thus, we conclude that 1,25D-induced monocytic differentiation, and CD14 expression in particular, are mediated through activation of ERK5-Mef2C-C/EBPβ signaling pathway, and that Mef2C does not seem to modulate cell cycle progression.
Adolescents' interpretations of conditional confidentiality assurances.

Abstract Purpose: To improve physicians’ discussions of confidentiality policies with adolescent patients. Method: Fifty-three students completed private semistructured interviews designed to explore adolescents’ interpretations of a statement explaining both the protections and limitations of confidentiality. Results: Results suggest strategies for explaining conditional confidentiality in a way adolescents’ understand and trust.
An atom-resolved view of silicon nanoclusters

Abstract Atomically resolved scanning tunneling microscope images of Si clusters deposited onto a Si(111)-7 × 7 substrate have been obtained. The clusters display a capping layer of widely spaced surface atoms analogous to the reconstructed surface of a bulk crystal. Site-specific variations in the electronic characteristics of cluster surface atoms are detected. Adsorption studies demonstrate size dependant reactivity of deposited clusters. Clusters are observed to collapse upon annealing to form epitaxial Si islands.
Expression and characterization of the catalytic domains of soluble guanylate cyclase: interaction with the heme domain.

The catalytic domains (αcat and βcat) of α1β1 soluble guanylate cyclase (sGC) were expressed in Escherichia coli and purified to homogeneity. αcat, βcat, and the αcatβcat heterodimeric complex were...
The involvement of the nucleus accumbens in the ability of rats to switch to cue-directed behaviours.

Abstract Previous studies have shown that the dorsal striatum is involved in switching arbitrarily behaviour (switching to non cue-directed behaviours). These experiments also revealed that switching behaviour with the help of currently available sensory information (switching to cue-directed behaviours) was not influenced when striatal function was blocked. A number of studies suggested that the nucleus accumbens could mediate the latter type of switching. For testing this hypothesis we used the swimming-test as it allows for studying separately both cue-directed and non cue-directed behaviours. Rats with cannulae aimed at the nucleus accumbens were forced to swim after injection of distilled water (AD) or d-amphetamine (1–10 μg/0.5 μ1) in a circular watertank from which there was no escape. Their behaviour was recorded and analysed according to the presence of cue-directed and non cue-directed behaviours. After six minutes a rope was introduced into the water-tank to determine whether the rats were able to change their behaviour with the help of this external stimulus as well. Rats treated with d-amphetamine showed an enhanced ability to switch to cue-directed behaviours in comparison with rats treated with AD. There was no effect on the ability to switch to non cue-directed behaviours. Furthermore there was a dose-dependent increase in the ability to escape along the rope. The results are taken as evidence that the nucleus accumbens is involved in switching to cue-directed behaviours.
Patterns of groundwater salinity changes in a deep continental-oceanic transect off the southeastern Atlantic coast of the U.S.A.

Abstract Manheim, F.T. and Paull, C.K., 1981. Patterns of groundwater salinity changes in a deep continental-oceanic transect off the southeastern Atlantic coast of the U.S.A. In: W. Back and R. Letolle (Guest-Editors), Symposium on Geochemistry of Ground-water — 26th International Geological Congress. J. Hydrol., 54: 95ndash;105. Investigations of formation-fluid salinities in a transect from western Georgia to the edge of the Blake Plateau off the coast of Georgia show surprisingly similar hydro-chemical features offshore and onshore. A fresh—brackish wedge of groundwater (>25g/kg total dissolved solids) lies beneath the shelf to a depth of ∼ 900 m. On land, brackish waters extend to a maximum depth of ∼ 1.2 km below sea level in Lowndes County, Georgia. In deeper horizons, hypersaline brines (>100g/kg) occur in Lower Cretaceous (?) strata. These strata have a pronounced evaporitic (anhydritic) character in the offshore segment. Strong salinity gradients in interstitial waters signify buried evaporite deposits at drill sites beneath the Blake Plateau.
The current status of gastrointestinal laser activity in the United States

The therapeutic applications of fiberoptic endoscopy in the field of gastroenterology are expanding. In the therapy of gastrointestinal bleeding, the initial results of laser photocoagulation have been encouraging. As of May 1, 1981, 388 patients have been treated for gastrointestinal bleeding at 12 centers in the United States. A tabulation of the results in this uncontrolled compilation reveals that initial hemostasis was achieved in 80 to 95% of patients. Applications of the laser in addition to the treatment of actively bleeding lesions include therapy of neoplastic and angiodysplastic lesions. There is a growing interest in the utilization of endoscopic laser therapy.
The chemical composition and submicroscopic morphology of Mycoplasma gallisepticum, avian PPLO 5969.

Studies have been carried out on the chemical composition and morphological subunits of Mycoplasma gallisepticum (avian PPLO 5969). The morphological units which were identified were cell membrane, double-stranded DNA, ribosomes and soluble protein. DNA and RNA base ratios were determined as was amino acid composition. An analysis of the lipid components was carried out. A very striking feature of these cells is the very small size and low total content of DNA.
Preparation of several trifluoroacetyl insulin derivatives.

Abstract The selective modification of the amino groups in insulin has been effected using phenyltrifluoroacetate or ethylthioltrifluoroacetate affording several trifluoroacetyl derivatives, where fluorine will serve as a reporter group for fluorine magnetic resonance studies. Insulin hydrochloride was reacted with one of the above reagents and imidazole in dimethyl-formamide. The resulting products were separated and purified using DEAE-Sephadex chromatography to yield 3 mono- and 3 di-trifluoroacetyl insulin products in addition to the tri- derivative. These derivatives were characterized by deamination, trypsin digestion and amino acid analysis. Radioimmunoassays indicated that these derivatives had immunoreactivities ranging from 60 to 89% of native insulin. Glycine A−1 -trifluoroacetyl-insulin afforded a crystalline derivative in the presence of Zn 2+ .
Estimating virus production rates in aquatic systems.

Viruses are pervasive components of marine and freshwater systems, and are known to be significant agents of microbial mortality. Developing quantitative estimates of this process is critical as we can then develop better models of microbial community structure and function as well as advance our understanding of how viruses work to alter aquatic biogeochemical cycles. The virus reduction technique allows researchers to estimate the rate at which virus particles are released from the endemic microbial community. In brief, the abundance of free (extracellular) viruses is reduced in a sample while the microbial community is maintained at near ambient concentration. The microbial community is then incubated in the absence of free viruses and the rate at which viruses reoccur in the sample (through the lysis of already infected members of the community) can be quantified by epifluorescence microscopy or, in the case of specific viruses, quantitative PCR. These rates can then be used to estimate the rate of microbial mortality due to virus-mediated cell lysis.