cssi/SciSciGPT-SciSciNet huggingface dataset:
Operative Technique and Lessons Learned From Surgical Implantation of the NeuroPace Responsive Neurostimulation® System in 57 Consecutive Patients.

Background The Responsive Neurostimulation (RNS)® System (NeuroPace, Inc) is an implantable device designed to improve seizure control in patients with medically refractory focal epilepsy. Because it is relatively new, surgical pearls and operative techniques optimized from experience beyond a small case series have yet to be described. Objective To provide a detailed description of our operative technique and surgical pearls learned from implantation of the RNS System in 57 patients at our institution. We describe our method for frame-based placement of amygdalo-hippocampal depth leads, open implantation of cortical strip leads, and open installation of the neurostimulator. Methods We outline considerations for patient selection, preoperative planning, surgical positioning, incision planning, stereotactic depth lead implantation, cortical strip lead implantation, craniotomy for neurostimulator implantation, device testing, closure, and intraoperative imaging. Results The median reduction in clinical seizure frequency was 60% (standard deviation 63.1) with 27% of patients achieving seizure freedom at last follow up (median 23.1 mo). No infections, intracerebral hemorrhages, or lead migrations were encountered. Two patients experienced lead fractures, and four lead exchanges have been performed. Conclusion The techniques set forth here will help with the safe and efficient implantation of these new devices.
Coronary Artery Disease Phenotype Detection in an Academic Hospital System Setting.

Background The United States, and especially West Virginia, have a tremendous burden of coronary artery disease (CAD). Undiagnosed familial hypercholesterolemia (FH) is an important factor for CAD in the U.S. Identification of a CAD phenotype is an initial step to find families with FH. Objective We hypothesized that a CAD phenotype detection algorithm that uses discrete data elements from electronic health records (EHRs) can be validated from EHR information housed in a data repository. Methods We developed an algorithm to detect a CAD phenotype which searched through discrete data elements, such as diagnosis, problem lists, medical history, billing, and procedure (International Classification of Diseases [ICD]-9/10 and Current Procedural Terminology [CPT]) codes. The algorithm was applied to two cohorts of 500 patients, each with varying characteristics. The second (younger) cohort consisted of parents from a school child screening program. We then determined which patients had CAD by systematic, blinded review of EHRs. Following this, we revised the algorithm by refining the acceptable diagnoses and procedures. We ran the second algorithm on the same cohorts and determined the accuracy of the modification. Results CAD phenotype Algorithm I was 89.6% accurate, 94.6% sensitive, and 85.6% specific for group 1. After revising the algorithm (denoted CAD Algorithm II) and applying it to the same groups 1 and 2, sensitivity 98.2%, specificity 87.8%, and accuracy 92.4; accuracy 93% for group 2. Group 1 F1 score was 92.4%. Specific ICD-10 and CPT codes such as “coronary angiography through a vein graft” were more useful than generic terms. Conclusion We have created an algorithm, CAD Algorithm II, that detects CAD on a large scale with high accuracy and sensitivity (recall). It has proven useful among varied patient populations. Use of this algorithm can extend to monitor a registry of patients in an EHR and/or to identify a group such as those with likely FH.
Natural gas prices, LNG transport costs, and the dynamics of LNG imports

According to the U.S. Energy Information Administration, LNG is projected to become a much larger share of U.S. natural gas consumption, rising from current levels of around 2.5% of total natural gas consumption to 12.4% by 2030. Because natural gas and LNG are substitutes, natural gas prices are expected to be an important determinant of LNG imports. Furthermore, an increasing share of LNG is traded under short-term contracts with spot shipments being diverted to markets offering the highest returns (netbacks). Relative natural gas prices as well as LNG transportation costs are important determinants of LNG netbacks. This paper examines the empirical relationship between U.S. LNG imports, the Henry Hub price of natural gas relative to U.K. and Asia gas prices, and a proxy for LNG transportation costs using monthly data from 1997 to 2007. Granger causality tests, error variance decomposition, and impulse response analyses using a VAR model are employed to establish Granger-causality as well as the dynamics of natural gas prices and LNG transportation innovations on LNG imports.
Outcomes and adverse effects of extremely high dose insulin infusions in ICU patients.

Abstract Purpose Describe the characteristics, hospital course, and outcomes of adult ICU patients receiving extremely high dose insulin infusions compared to those with lower insulin requirements. Materials and methods Retrospective observational study of 128 adult ICU patients receiving IV insulin infusions at a large academic medical center. Extremely high dose insulin infusions were defined as maximum rate ≥ 35 units/h. The primary endpoint was rate of hypoglycemia (BG Results Analysis included 32 patents with extremely high dose insulin infusions and 96 patients without, and most had a goal BG 100–150 mg/dL. Patients in the extreme group were more likely to have type 2 diabetes, a higher median hemoglobin A1c, preadmission insulin, be admitted for a medical reason, and receive inpatient steroids. The extreme group were more likely to experience hypoglycemia ( Conclusions ICU patients with extremely high dose insulin infusions had more hypoglycemia and took longer to achieve glucose targets compared to those with lower requirements. An individualized approach may be required for appropriate management.
Semiclassical Theory Based on Euclidean Path Integral

The quantum mechanics courses include semiclassical methods based on certain representation of the wave function, starting with the celebrated Bohr–Sommerfeld quantization condition, applied to the oscillator and hydrogen atom, and the Wentzel–Kramers–Brillouin (WKB) approximation, developed in 1926. Unfortunately, subsequent study has shown that generalization of those to systems with more than one degree of freedom, as well as to systematic order-by-order account for quantum fluctuations are difficult.
Voluntary running of defined distances alters bone microstructure in C57BL/6 mice fed a high-fat diet

Obesity increases the risk for pathological conditions such as bone loss. On the other hand, physical exercise reduces body adiposity. To test the hypothesis that physical activity improves bone qu...
Poverty comparisons with non-compatible data: theory and illustrations

Comparisons of poverty rates are only rarely based on identical underlying definitions of welfare. The authors examine the sensitivity of poverty rates calculated from alternative definitions of consumption. They consider what theory can say about the direction of bias in comparisons and show that under certain conditions robust comparisons are possible. Data from Ecuador, El Salvador, and Pakistan show that the magnitude of biases can be substantial. Their robustness result is used as a baseline to explore the tradeoffs involved in aggregating noisy expenditure components. Although nonfood expenditures are often thought to be especially poorly measured, the authors' data indicate that the more comprehensive is the measure of consumption spending, the better it is as a measure of welfare.
Kavitationserisionsuntersuchungen mit Werkstoffproben aus Chrom-Nickelstahlguß und Polyamidguß

Eim im Pumpenbau bewahrter Chrom-Nickel-Stahlgus und eine neuartige Polyamidvariante wurden bei Kavitationserosionsbelastung im Magnetostriktionschwinger untersucht. Aufgrund der ermittelten Massenabtrags-Laufdauerkurven und Probenoberflachenbilder sind beim Stahlgus ausgepragte Werkstoffschaden feststellbar. An allen Polyamidproben sind dagegen weder Massenverluste noch Beschadigungen der Probenoberflachen zu erkennen. Cavitation Erosion Tests with Polyamid-Specimens and Stainless-Steel-Specimens The Darmstadt vibratory cavitation erosion method, cavitation tests were performed on two materials: a proven chromium-nickel alloy and a recently introduced polyamid grade. Time studies based on the above test method resulted in pronounced damage to the chromium-nickel alloy, as documented in mass loss curves and specimen surface pictures. In contrast, all polyamid specimens sustained no damage, i.e. no mass loss, no surface damage resulted.
Bioluminescence Potential in the Transition Zone to Very Shallow Water (VSW)

Abstract : The long-term goal is to advance our understanding of the ecology of bioluminescent organisms and the mechanisms governing the temporal and depth-dependent variability of bioluminescence in the coastal ocean. With improvements in technology, finer-scale resolution and concurrent physical, chemical and biological data are available to advance our understanding of the forcing mechanisms governing the temporal and depth-dependent variability of bioluminescence in environments of Naval relevance.
Groundwater availability in the Atlantic Coastal Plain of North and South Carolina

Bruce Campbell1, Matt Petkewich2, Alissa Coes3, and Jason Fine4 1 USGS Hydrologist, Columbia, SC; bcampbel@usgs.gov 2 USGS Hydrologist, Columbia, SC; mdpetkew@usgs.gov 3 USGS Hydrologist, Tucson, AZ; alcoes@usgs.gov 4 USGS Hydrologist, Raleigh, NC; jmfine@usgs.gov BACKGROUND Ground-water withdrawals from Atlantic Coastal Plain aquifers in North Carolina (NC) and South Carolina (SC) have increased over the past 15 years in response to demands for water for a rapidly growing population. The 2000 census report indicates that the combined populations of the NC and SC Coastal Plain counties totaled nearly 6 million people, representing about 40 percent of NC’s total population and about 63 percent of SC’s total population. The populations of Coastal Plain counties in both states is expected to increase between 13 and 14 percent by 2015. Concern about adequate ground-water supplies and declining ground-water levels in the Coastal Plain of the Carolinas dates back to the early part of the 20th century. As a result, Capacity Use Areas (CUA) have been established to regulate ground-water withdrawals. NUMERICAL MODEL CONSTRUCTION
In Memoriam: C. Paul Perry

The field of pain medicine suffered the loss of one of its pioneers in the recent death of Dr. C. Paul Perry, May 4, 2008. Dr. Perry was a superb physician with abundant clinical skills and knowledge of diagnosis and treatment of pelvic pain. He also was an ardent spokesman for improvement of the care of women with chronic pelvic …
Inflation as a probe of short distance physics

We show that a string-inspired Planck scale modification of general relativity can have observable cosmological effects. Specifically, we present a complete analysis of the inflationary perturbation spectrum produced by a phenomenological Lagrangian that has a standard form on large scales but incorporates a string-inspired short distance cutoff, and find a deviation from the standard result. We use the de Sitter calculation as the basis of a qualitative analysis of other inflationary backgrounds, arguing that in these cases the cutoff could have a more pronounced effect, changing the shape of the spectrum. Moreover, the computational approach developed here can be used to provide unambiguous calculations of the perturbation spectrum in other heuristic models that modify trans-Planckian physics and thereby determine their impact on the inflationary perturbation spectrum. Finally, we argue that this model may provide an exception to constraints, recently proposed by Tanaka and Starobinsky, on the ability of Planck-scale physics to modify the cosmological spectrum.
Programming language methods in computer security

This invited talk will give a personal view of the field of computer security and summarize some ways that methods from the study of programming language principles can be applied to problems in computer security. Some background information is provided here in this short document.
Synthesis and Structures of Cadmium Carboxylate and Thiocarboxylate Compounds with a Sulfur-Rich Coordination Environment: Carboxylate Exchange Kinetics Involving Tris(2-mercapto-1-t-butylimidazolyl)hydroborato Cadmium Complexes, [TmBut]Cd(O2CR)

A series of cadmium carboxylate compounds in a sulfur-rich environment provided by the tris(2-tert-butylmercaptoimidazolyl)hydroborato ligand, namely, [TmBut]CdO2CR, has been synthesized via the reactions of the cadmium methyl derivative [TmBut]CdMe with RCO2H. Such compounds mimic aspects of cadmium-substituted zinc enzymes and also the surface atoms of cadmium chalcogenide crystals, and have therefore been employed to model relevant ligand exchange processes. Significantly, both 1H and 19F NMR spectroscopy demonstrate that the exchange of carboxylate groups between [TmBut]Cd(κ2-O2CR) and the carboxylic acid RCO2H is facile on the NMR time scale, even at low temperature. Analysis of the rate of exchange as a function of concentration of RCO2H indicates that reaction occurs via an associative rather than dissociative pathway. In addition to carboxylate compounds, the thiocarboxylate derivative [TmBut]Cd[κ1-SC(O)Ph] has also been synthesized via the reaction of [TmBut]CdMe with thiobenzoic acid. The molecu...
Spectroscopic Determination of the Thermodynamics of Cobalt and Zinc Binding to GATA Proteins

Vertebrate GATA proteins regulate processes that are vital to development, and each possesses two tandem GATA finger domains: an N-terminal GATA finger and a C-terminal GATA finger. These GATA fingers require Zn2+ to fold, to bind DNA recognition elements, and to regulate transcription. While the GATA-1 C-terminal finger is necessary and sufficient to bind to single GATA DNA sites, the N-terminal finger interacts with DNA such that the double finger unit (DF domain) has a binding and transactivation profile that is tuned by the DNA-binding site. Co2+ was used as a spectroscopic probe in a series of competition titrations to determine the affinity of Co2+ and Zn2+ for the C-terminal finger from chicken GATA-1 and the double finger from human GATA-1 (referred to in this report as CF and DF). For CF, these experiments yielded KbCo = 1.0 (±1.3) × 107 M-1 and KbZn = 2.0 (±1.3) × 1010 M-1. For DF, these experiments yielded equilibrium constants for the process of two M2+ binding to form M2+2-DF of β2Co = 2.5 (...
New health techniques and technologies

A large segment of the medical community views the invasion of technology into medical practice with concern, if not alarm. The current trends should receive warmer welcome since they now show real promise of being able to spare the valuable time of physicians from certain types of routine activity which do not require the extensive training of health professionals. If new diagnostic tools in the hands of well-trained technicians can provide consistently reliable data, displayed to physicians with greater clarity and less redundancy, then all participants in the health care delivery system must benefit, including the patient. The ultimate success of current efforts to provide new forms of medical instrumentation will depend in large measure on supplementing the physicians' own senses without interfering with his decision making process. The new technology should not affect the essential doctor-patient relationship, but should free physicians' time to be devoted to those aspects of medical practice for which his long training and experience is expressly intended. Comprehensive biomedical engineering programs composed of engineers and life scientists working collaboratively on problems of mutual interest provide an important potential source of the new techniques and technologies so vitally needed to improve the quality of medical care at minimal cost.
Reporting Assessment Results to Parents.

(2002). Reporting Assessment Results to Parents. Journal of Physical Education, Recreation & Dance: Vol. 73, No. 8, pp. 20-24.
Nonparametric measures of dependence for biometric data studies

This paper explores the possibility of using nonparametric dependence characteristics to evaluate biometric systems or algorithms. The extensions of classical rank correlation coefficients to the case when only a given number of top matches is used, are investigated. Difficulties with these coefficients in capturing the total correlation are noted. A version of a scan statistic, which measures co-occurrence of rankings for two arbitrary algorithms, is studied. The exact covariance structure of this statistic is found for a pair of independent algorithms. In the general case, its asymptotic normality is derived by using classical results on linear rank statistics. The concept of copula is shown to be useful for the study of nonparametric dependence characteristics. The results are applied to an example from the FERET (Face Recognition Technology) program. It is demonstrated that the random scores of considered recognition methods can be modeled by a two-parameter family of copulas exhibiting strong tail dependence.
Stable calcium isotopic compositions of Hawaiian shield lavas: Evidence for recycling of ancient marine carbonates into the mantle

We report high-precision 44Ca/40Ca measurements (2σm < 0.06‰) of Hawaiian shield stage tholeiites. Our data reveal ∼0.3‰ variation in their 44Ca/40Ca, which comprises ∼20% of the 44Ca/40Ca variation observed in global carbonates. The 44Ca/40Ca variation is correlated with Sr/Nb and 87Sr/86Sr, and this pattern is best explained by adding up to 4% ancient carbonate into the Hawaiian plume. Mass-balance calculations show that up to 40% of the Ca budget and 65% of the Sr budget in some Hawaiian (Makapuu-stage Koolau) lavas are derived from recycled carbonates. Our finding demonstrates, for the first time with the application of Ca isotopes, that ancient recycled carbonates are important components of mantle plumes which feed some of the largest terrestrial volcanoes. Thus, recycling of carbonates into the mantle is an essential part of the global Ca and C cycles.
A shock tube study of the NH2+NO2 reaction

The overall rate coefficient and the branching ratio of the NH 2 +NO 2 reaction were determined inshock tube experiments. Benzylamine (C 6 H 5 CH 2 NH 2 ) was used as a thermal source of the NH 2 radical. To obtain the overall rate coefficient, the NH 2 mole fraction was measured using frequency-modulation absorption spectroscopy. For the branching ratio deterrnination, the IR emission from N 2 O was mornitored. During the N 2 O emission experiments, the NO 2 mole fraction was measured simultaneously using a tunable diode laser. The mesured species profiles were interpreted using a detailed 118-reaction mechanism, which was based on the reaction mechanism from our previous study of the NH 2 +NO reaction with added reactions involving N 2 O and NO 2 . The overall rate coefficient is (5.5±0.8)×10 12 cm 3 mol −1 s −1 in the temperature range, 1330–1527 K, and pressure range 1.31–1.49 bar. This value is 1.6 times the result of Glarborg et al. and 2.5 times that extrapolated from the expression reported by Park and Lin. The measured branching ratio for the N 2 O+H 2 O product channel of the NH 2 +NO 2 reaction was 0.17±0.04 for the temperature range 1319–1493 K, which is consistent with the results of Park and Lin and Quandt and Hershberger at lower temperatures.
The utility of preoperative endometrial sampling for the detection of uterine sarcomas

Abstract Objective Uterine sarcomas are aggressive cancers, often not recognized prior to surgical exploration. The goal of this study was to determine the utility of endometrial sampling in detecting uterine sarcomas and to examine factors associated with diagnostic inaccuracy. Methods All uterine tumors identified at hysterectomy from 1990 to 2006 were reviewed. Included patients underwent preoperative endometrial sampling reviewed at our center. Pathologic data was documented through review of hospital records. Statistical analysis was performed using Chi square test. Results 938 patients were identified. Preoperative sampling was available for review in 730 (78%) subjects. Uterine sarcomas occurred in 142 patients; 72 (51%) underwent preoperative sampling. Overall, endometrial sampling identified an invasive tumor in 84% (600/713), and the correct histology in 79% (564/713). Among women with sarcomas, preoperative sampling suggested an invasive tumor in 86% (62/72) and predicted the correct histologic diagnosis in 64% (46/72). The rate of detection of an invasive cancer by preoperative sampling was not statistically different among sarcomas and epithelial tumors (86% vs. 84%, p =0.76). Preoperative sampling was significantly less reliable in predicting the correct histology for uterine sarcomas (64% vs. 81%, p p =0.84). Conclusions Endometrial sampling has a significantly lower predictive value in diagnosing uterine sarcomas compared to epithelial uterine malignancies. Biopsy and curettage have similar accuracy. Novel diagnostic techniques are needed to accurately identify uterine sarcomas preoperatively.
The Friends and Neighbors Effect in Judicial Retention Elections

HIS is a study of judicial retention elections for major trial court judges. Judicial retention elections differ from the more traditional partisan or nonpartisan elections in several respects. The absence of traditional voting cues including party labels, candidate appeals, incumbency, campaigns, and relatively fewer issues makes these plebiscites a most interesting topic for examination. One of the few traditional voting cues present in judicial retention elections is the cue of "friends and neighbors," which has received little scholarly attention (Key 1949; Dubois 1979; Griffin and Horan 1982). This article will rectify this oversight by empirically examining the "friends and neighbors" effect in judicial retention elections. It is said that all politics are local politics. We found it surprising therefore, that one of the voting cues which has received very little attention is "friends and neighbors." Voting on the basis of friends and neighbors is a Babbit-like calculated promotion of local interest. The candidate garners support (votes) "not primarily for what he stands for or because of his capacities, but because of where he lives" (Key 1949: 37). Studying the oneparty politics of the South, where many of the traditional voting cues were absent, Key called that appeal "back the home-town boy" irrelevant, but he was careful to point out that in the absence of traditional voting cues, such an appeal based on boosterism "can exert no little influence over an electorate" (Key 1949: 41). Trial court personnel were chosen as the subjects of this study because 90 percent of all court business of this nation takes place in the state trial courts. A very small percentage of cases are appealed and reviewed by higher courts.
Factors Influencing Response to Growth Hormone Therapy in Patients with Turner Syndrome † 396

Factors Influencing Response to Growth Hormone Therapy in Patients with Turner Syndrome † 396
The line contact problem of elastohydrodynamic lubrication I. Asymptotic structure for low speeds

This paper reports the first formal asymptotic solution to the line contact problem of elastohydrodynamic lubrication (EHL), a fundamental problem describing the elastic deformation of lubricated rolling elements such as roller bearings, gear teeth and other contacts of similar geometry. The asymptotic regime considered is that of small λ , a dimensionless parameter proportional to rolling speed, viscosity and the elastic modulus. The solution is shown to possess four regions: a zone where the lubricating film is both thin and slowly narrowing and which is closely related to the contact area that occurs in the absence of lubricant, an upstream inlet zone of low pressure, and two thin layers on either side of the contact zone. The solutions in the first two just-mentioned zones are given by simple analytical expressions. The solutions in the two thin layers are obtained from two universal functions obtained by Bissett & Spence ( Proc. R. Soc. Lond . A 424, 409 (1989)). Although these two functions, related to the local film thickness, are obtained by numerical techniques by Bissett & Spence, it should be emphasized that all cases in the asymptotic regime considered are hereby solved definitively without recourse to further computation. Although some features of this structure have been suggested by other solution approaches, generally, these are numerical or ad hoc approximations. See the texts by Johnson ( Contact Mechanics , pp. 328 (1985)) and Dowson & Higginson ( Elasto-hydrodynamic lubrication (1977)), this work provides a formal mathematical basis for understanding most of the principal features of EHL. The solution provides a simple formula for minimum film thickness and displays the sharp narrowing of the lubricating film in the thin layer near the exit. In the basic asymptotic solution provided here, the dimensionless pressure-viscosity coefficient, α , is assumed to be O (1), and in this parameter regime, no pressure spike will occur. By comparing with the work of Hooke ( J. mech. Engng Sci . 19(4), 149 (1977)), we can show that an incipient pressure spike occurs when α becomes as large as O ( λ -1/5 ). However, asymptotic solutions in this latter parameter regime require new numerical solutions for each case of interest and are not pursued here.
The effects of the administration of fenoprofen or indomethacin to rat dams during late pregnancy, with special reference to the ductus arteriousus of the fetuses and neonates

Abstract Examination of a series of normal neonatal rats showed that the ductus arteriosus did not begin closing until approximately 16 to 20 min after birth and was usually completely closed by 85 to 98 min after birth. Pregnant rats were orally dosed twice daily for 1.5 to 5 days with 50 mg/kg of fenoprofen calcium, 1.6 mg/kg of indomethacin, or vehicle (1% methylcellulose), beginning 18 days after mating. The fenoprofen calcium treatment resulted in premature ( in utero ) closure of the ductus arteriosus in 4 to 10% of the offspring of dams treated for 3.5 to 5 days. The indomethacin treatment caused premature ( in utero ) ductal closure in 1 to 3% of the offspring after 4.5 to 5 days. Both treatments also caused a high incidence of maternal mortality after 4.5 to 5 days (38 to 50% for fenoprofen calcium and 13 to 25% for indomethacin) and increased the duration of gestation or blocked parturition. Treatment of rat dams with 4 mg of progesterone daily from 18 through 22 days after mating blocked parturition, but the ductus arteriosus was not closed in any of the fetuses that were retained in utero . This suggests that the in utero closure of the ductus found in fetuses of dams treated with fenoprofen calcium or indomethacin was not a consequence of retention of the fetuses in the uterus.
Long-term health outcomes of a decision aid: data from a randomized trial of adjuvant! In women with localized breast cancer.

Purpose . Women with localized breast cancer face difficult decisions about adjuvant therapy. Several decision aids are available to help women choose between treatment options. Decision aids are known to affect treatment choices and may therefore affect patient survival. The authors aimed to model the effects of the Adjuvant! decision aid on expected survival in women with early stage breast cancer.Patients and Methods. Data were obtained from a randomized trial of Adjuvant! (n = 395). To calculate the effects of the decision aid on survival, the authors used the Adjuvant! survival predictions as a surrogate endpoint. Data from each arm were entered separately into statistical models to estimate change in survival associated with receiving the Adjuvant! decision aid.Results. Most women (∼ 85%) chose a treatment option that maximized predicted survival. The effects of the decision aid on outcome could not be modeled because a small number of women (n = 12, 3%) chose treatment options associated with a lar...
Early ontogeny of catecholaminergic cell lineage in brain and peripheral neurons monitored by tyrosine hydroxylase-lacZ transgene

Abstract As the first and rate limiting enzyme in the biosynthetic pathway for catecholamine (CA) neurotransmitters, tyrosine hydroxylase (TH) is a specific phenotypic marker for CA cells in the central and peripheral nervous systems of adult animals. During embryogenesis, TH expression appears permanently within cells destined to be CA-secreting during adult life, and transiently in several cell types that will not express TH in adulthood. In this study, we examined the early ontogeny of TH expression in transgenic mouse embryos by following the expression of a lacZ reporter, driven by the tissue-specific promoter of the rat TH gene. The lacZ reporter product, β-galactosidase (β-gal), visualized by X-gal staining, first became apparent in primordia of sensory ganglia serving the glossopharyngeal (IX) and vagal (X) cranial nerves at embryonic day (E)9.0. Between E9.5 and E10.5, β-gal expression extended to the remaining cranial sensory ganglia serving the trigeminal (V) and facial (VII) nerves, dorsal root ganglia, ventrolateral neural tube and sympathetic ganglion primordia. During that same period, the first β-gal expression in the embryonic brain also appeared within distinct regions, such as the ventral prosencephalon, the ventral and dorsolateral mesencephalon and the rostral and caudal rhombencephalon. The level of β-gal expression in all these tissues decreased at E13.5, but a distinct adult pattern of β-gal expression started to emerge in the substantia nigra and ventral tegmental area in the central nervous system and the adrenal medulla in the periphery. Our findings indicate that the proximal 9.0 kb of the 5′ promoter region of the rat TH gene encodes sufficient information to direct development of the appropriate catecholaminergic lineage cells in the central and most peripheral nervous systems during embryogenesis.
Microbiology: pathogen drop-kick.

To set the scene for its replication, the bacterium Legionella pneumophila exploits its host cells' Rab1 protein. This pathogen seems to use minimal resources to mimic the normal cycle of Rab1 activity. One of the properties that makes the most common Legionnaires' disease pathogen so virulent is its ability to exploit the vacuole formed inside host macrophages when they ingest the bacterium. The vacuole is meant to be as far as the pathogen gets, the site where host enzymes destroy it. But Legionella pneumophila hijacks the vacuole and directs it to be transported to the endoplasmic reticulum, where the bacteria multiply. Two bacterial proteins involved in this process have now been identified. DrrA protein turns on a molecular switch, Rab1, and subverts its function to allow the endoplasmic reticulum and the vacuole to fuse. LepB then turns off the Rab1 switch once the bacteria are in the endoplasmic reticulum.
The turnover time of dietary cholesterol in the lactating rat.

The secretion of dietary 4-14C-cholesterol into milk of the rat was determined as a function of post-feeding time by a single dose technique. The time interval which elapsed before maximum specific radioactivity was reached in milk (17–20 hr after maximum activity in the serum) suggests a route through the mammary gland involving transport of the cholesterol by intracellular membranes. It also suggests that the exogenous cholesterol is incorporated into the milk fat globule membranes rather than into the fat globules during their synthesis within the cell.
A numerical evaluation of a hollow fiber extractive fermentor process for the production of ethanol

The economics of a process for the production of ethanol employing a hollow fiber extractive fermentor have been investigated. A computer simulation of the process incorporating a mathematical model of the fermentor was used to calculate the mass and energy balances. The results of the process simulation were read into a computer spreadsheet programmed with the economic calculations from which a final ethanol product cost was obtained. The process was found to be as competitive as conventional fermentation processes even at the currently high cost — $4/sq ft — of hollow fibers. It was determined that the 1986 price of 46.2 cents/L of ethanol produced by the process would be reduced by 1.8 cents/L for every $1/sq foot drop in the price of hollow fibers. A comparison of this process with conventional fermentation processes indicates that its potential savings lie in its ability to use a concentrated sugar feed, and the fermentor's increased productivity and ability to produce a concentrated ethanol stream which is removed by the extracting solvent.
Quantitative high-performance liquid chromatography analysis of DNA oxidized in vitro and in vivo

Oxidative modification of genetic material has been implicated as a factor in carcinogenesis, particularly during promotion and progression, and therefore there is a need for sensitive detection of oxidized DNA bases. We developed a method that can be applied to DNA isolated from any source and used to simultaneously quantify oxidized nucleosides without a need to prelabel the DNA or use destructive hydrolytic procedures. This method is based on: (a) enzymatic DNA digestion; (b) HPLC separation of the resultant nucleosides; (c) acetylation of the oxidized nucleosides with [3H]Ac2O (acetic anhydride); (d) removal of the radioactive debris; and (e) quantitative analysis of tritiated nucleoside acetates by HPLC. Enzymatic DNA digestion was optimized using DNase I in the presence of Mg2+ (pH 7), followed by nuclease P1 in the presence of Zn2+ (pH 5.1) and alkaline phosphatase (pH 7.5). Analysis of DNA oxidized with H2O2 in the presence of Fe2+/EDTA for 30 min showed that the levels of 8-OHdG (8-hydroxy-2'-deoxyguanosine) were increased 2.7-fold, HMdU (5-hydroxymethyl-2'-deoxyuridine) 3.15-fold, and FdU (5-formyl-2'-deoxyuridine) 2.5-fold. Although the (-)-isomer of cis-dTG (cis-thymidine glycol) was enhanced 2.3 times, the (+)-isomer remained virtually unchanged. Analysis of DNA isolated from epidermal cells of mice treated in vivo with the tumor promoter TPA (12-O-tetradecanoylphorbol 13-acetate) showed 4.8-, 2.7-, and 8.7-fold increases in the levels of total cis-dTG, 8-OHdG, and HMdU, respectively, and of some unknown DNA oxidation products. These results prove applicability of the 3H-postlabeling method to the analysis of DNA (and potentially RNA) isolated from many sources, including animals and humans.
“You're lying to Jesus!”: Humor and play in a discussion about homelessness

This study applies recent theories about humor to a sample of talk among a group of young adults about the issues and problems associated with homelessness. In this conversation, participants demonstrate a pattern of joking and language play that expresses a complex and ambivalent set of attitudes and feelings toward homelessness and toward the homeless as both outcasts and refugees from conventional society. Humor is used both to express complex responses to homelessness and as a tool for managing the tone and direction of the conversation. The results demonstrate how the identification of patterns of joking and wordplay can provide insights into how people accomplish task-oriented objectives as well as relational and interactive objectives in e veryday talk.
High-resolution extreme-ultraviolet spectroscopy of potassium using anti-Stokes radiation

The use of a new extreme-ultraviolet radiation source based on spontaneous anti-Stokes scattering for high-resolution absorption spectroscopy of transition originating from the 3p6 shell of potassium is reported. The region from 546.6 to 536.8 A is scanned at a resolution of about 1.2 Kayser. Within this region, four previously unreported lines are observed.
LEED and surface structure

Abstract The present status and future prospects of atomic scale surface structure determination by LEED are surveyed. A case is made that LEED intensity analysis has done well on many simple systems and that extension to more complex systems does not require conceptual changes, but improvement in technique. Systems are classified by difficulty and some structural results of special interest are discussed. Some reasons for success and suggestions for improvement are noted.
General base-catalyzed ester hydrolysis as a model of the “charge-relay” system☆

Abstract The validity of the “charge-relay” system in serine esterases was examined by use of the general base-catalyzed hydrolysis of ethyl chloroacetate ( I ) as a model system. The general base catalytic rate for 2-benzimidazoleacetic acid ( II ) exhibited an eightfold positive deviation from the Bronsted plot including benzimidazole, imidazole, N -methylimidazole ( V ), and acetate ion, though in nucleophilic catalysis of the hydrolysis of p -nitrophenyl acetate, the point for II conformed to the Bronsted relationship together with imidazole and benzimidazole derivatives. The positive deviation of II from the Bronsted plot for the general base-catalysis was attributed to the cooperativity of the carboxyl group of II , the imidazolyl group of II , and the hydroxyl group of water. The present result provides support for the “charge-relay” system. Furthermore, the (essentially) total loss of the enzymatic activity due to N-3 methylation of histidine-57 in α-chymotrypsin is discussed in comparison to the general base-catalysis of V in the hydrolysis of I , which is also favorable for the “charge-relay” system.
MCLUST: Software for Model-Based Cluster Analysis

MCLUST is a software package for cluster analysis written in Fortran and interfaced to the S PLUS commercial software package It implements parameterized Gaussian hierarchical clustering algorithms and the EM algorithm for parameterized Gaussian mixture models with the possible addition of a Poisson noise term MCLUST also includes functions that combine hierarchical clustering EM and the Bayesian Information Criterion BIC in a comprehensive clustering strategy Methods of this type have shown promise in a number of practical applications including character recognition tissue segmenta tion mine eld and seismic fault detection identi cation of textile aws from images and classi cation of astronomical data A web page with related links can be found at
Measuring and causes of inequality in farm sizes in the United States

This article examines the notion of farm size inequality expressed as sales inequality in the United States. The farm size index (FSI) is developed as a measure of farm size inequality. FSIs are calculated for the farming sector in all 50 states and large variation in farm size across the states and over time is determined. The largest FSIs are calculated for a number of Southern, Southwestern, and Pacific states. Increasing FSIs over time are observed in all states as well. The spatial and temporal (between 1987 and 1997) differences in FSIs are explained by running a pooled, cross-sectional time-series model. The most influential variables accounting for the differences have to do with the ownership structure, where a larger presence of individual and family farms relative to corporate farms and cooperatives leads to a lower degree of farm size inequality. Also, states and regions having relatively larger number of farms owned by minorities have higher FSIs. Shrinking opportunities in the agricultural sector relative to the rest of the economy, primarily services, are reflected in a declining share of agricultural sector state income in total gross state product (GSP). This in turn leads to an increase in the farming sector's FSI suggesting that only larger, more profitable operations are the likely candidates to pursue farming activities. Finally, grains farming regions have all lower degree of farm size inequality than livestock or fruits and vegetables regions. Profitable grains farming requires relatively large farm size and equipment investments, which leads to a relatively homogeneous structure of grains farms. A larger variation in the size of profitable farm operations is possible in fruits and vegetables and livestock. This leads to the existence of a large number of very small but still sustainable farms, and a relatively small number of large farms that capture most of market sales share.
Bariatric surgery: Creating new challenges for the endoscopist

The surgically altered GI tract provides the GI endoscopist with a challenging array of problems. Few operations are as creative and problematic as those encountered in the patient who has undergone bariatric surgery. Although the overwhelming majority of patients subjected to present-day bariatric procedures achieve dramatic success in terms of both weight reduction and improvement or correction of comorbidities, a minority of patients experience diverse GI symptoms, inadequate weight loss, or a combination of both. These adverse outcomes frequently eventuate a GI consultation. With this is mind, the present review addresses the current epidemic of obesity, its surgical management, and the implications for the GI endoscopist.
Dehumidification and Simultaneous Removal of Selected Pollutants from Indoor Air by a Desiccant Wheel Using a 1M Type Desiccant

Solid-desiccant dehumidifiers are increasingly becoming an integral part of desiccant based air-conditioning systems because of their effective handling of latent heat loads compared to conventional vapor compression units. In these units, either a silica gel or a molecular sieve is used for dehumidification of air. Both of them have the capability to co-adsorb various chemical pollutants during dehumidification of air. However, the shape of the isotherm for water vapor on these materials is not favorable for desiccant cooling applications. A mixture (1M desiccant) containing a silica gel, a molecular sieve, and a hydrophobic molecular sieve that was coated on an aluminum foil was studied for its capability for simultaneous removal of moisture and some selected pollutants from air. Experimental data were obtained in a fixed bed adsorber that simulated the operation of a rotary desiccant wheel. Air to be dehumidified and cleaned and the hot regeneration air were cycled in a specific time interval through this bed. The shape of the water isotherm on 1M desiccant was found to be in between that of silica gel and molecular sieve 13{times}, but its uptake capacity was significantly lower than that of either silica gel or molecular sieve. A flow rate ofmore » about 100 L/min that provided a face velocity of about 132 cm/s was used in the adsorption step. The flow rate during regeneration was about 50 L/min. The temperature of the inlet air was about 23 C and its relative humidity was varied between 20% and 80%. The concentrations of pollutants were as follows; carbon dioxide: 1050 and 2300 ppm; toluene: 32 ppm; 1,1,1-trichloroethane: 172 ppm, and formaldehyde: 0.35 ppm. A complete breakthrough of all the pollutants was observed during an adsorption cycle.« less
The development of students' graphical understanding of the derivative

Abstract This paper is part of a series of studies by the Research in Undergraduate Mathematics Education Community (RUMEC), concerning the nature and development of college students' mathematical knowledge. The present study explores calculus students' graphical understanding of a function and its derivative. An initial theoretical analysis of the cognitive constructions necessary for this understanding is given. An instructional treatment designed to help foster the formation of these mental constructions is described, and results of interviews, conducted after the implementation of the instructional treatment, are discussed. The understanding demonstrated by these students is analyzed according to the Action-Process-Object-Schema (APOS) theoretical framework. Based on the data collected as part of this study, a revised epistemological analysis for the graphical understanding of the derivative is proposed. Moreover, a comparative analysis is made of performance of students using the instructional treatment we designed with students taking a traditional calculus course. Although this analysis is flawed in many ways, it does suggest that the students whose course was based on the theoretical analysis of learning that we give here may have had more success in developing a graphical understanding of a function and its derivative, than students from traditional courses.
Troglitazone Lowers Islet Fat and Restores Beta Cell Function of Zucker Diabetic Fatty Rats

The thiazolidinedione compound troglitazone, which is used to treat non-insulin-dependent diabetes mellitus (NIDDM) in man, is also effective in the adipogenic NIDDM of Zucker diabetic fatty (ZDF) rats. To test the "lipotoxicity hypothesis," which attributes the beta cell dysfunction of adipogenic NIDDM to an excessive accumulation of fat in the pancreatic islets, we sought to determine if troglitazone-mediated amelioration of beta cell function in islets of ZDF rats might be associated with a reduction in their elevated triglyceride (TG) content. Troglitazone (10 microM) in the culture medium reduced the TG content of ZDF rats by 52%; this was reflected by decreased esterification and increased oxidation of [3H]palmitate. Glycerol-3-phosphate acyltransferase mRNA fell by 57% and acyl-CoA synthetase mRNA by 67% (brain isoform) and 38% (liver isoform), all consistent with the effects of troglitazone on TG metabolism. The 52% decrease in islet TG was accompanied by >30- and 2-fold improvements in glucose- and arginine-stimulated insulin secretion, respectively. We conclude that troglitazone exerts direct lipopenic activity in normal islets and in islets of obese prediabetic ZDF rats; in the latter, this correlated with improvement in beta cell function. The results are consistent with the lipotoxicity hypothesis for adipogenic diabetes.
Male and female correlations for taster (P.T.C.) phenotypes and rate of adolescent development.

Growth and development from infancy to age 18 years in tasters and non-tasters of phenylthiocarbamide (P.T.C.) were studied in 50 female and 44 male subjects. Taster girls reached all indices of maturation an average of 3.8 months earlier than non-taster girls. The reverse was true for boys, non-tasters maturing on average 6.2 months earlier than tasters. For both sexes, there was a significant correlation between an overall Maturity Index and P.T.C. sensitivity, positive for girls and negative for boys. Thirty-two of the females and 20 of the males could be classified according to P.T.C. genotype. For these, the onset, midpoint, and end of the pubertal growth spurt was estimated. Heterozygotes reached these points at times intermediate to homozygotes. Taster females preceded non-taster females and non-taster males preceded taster males by about 6 months. The finding of reversed associations between P.T.C. phenotype and maturation in males and females implies that factors underlying the P.T.C. polymorphism may not be confined to mediation through thyroid metabolism, but may also involve other complex pathways of the hypothalamic-pituitary-gonadal axis, particularly those of the sex hormones. The data were examined for evidence of whether or not the findings could be related to a means of maintaining the P.T.C. polymorphism. A significant negative assortative mating pattern was found. This accords with reports from the literature indicating personality differences between early and late maturers and a tendency for spouses to have similar personality characteristics. However, disassortative mating alone could not produce a stable equilibrium. A hypothesis for the maintenance of the P.T.C. polymorphism is developed on the assumption that the timing of puberty is related to reproductive fitness and subject to balancing selection. Heterozygotes for P.T.C. would be at an advantage because they have intermediate maturation times. In this small sample, P.T.C. heterozygotes were also found to produce more offspring than homozygotes.