cssi/SciSciGPT-SciSciNet huggingface dataset:
Sacral chordoma: 40-year experience at a major cancer center.

OBJECTIVE: Sacral chordomas are relatively rare, locally invasive, malignant neoplasms. Despite surgical resection, adjuvant radiation therapy, and chemotherapy, recurrence is common. This study reviews our experience during the last 40 years at The University of Texas M.D. Anderson Cancer Center, to determine the effects of various treatment methods on the overall course of this disease process. METHODS: A retrospective study was performed. From 1954 to 1994, 27 patients with sacral chordomas were evaluated at our institution. RESULTS: There were 19 male and 8 female patients, with a mean age of 56 years (range, 27-80 yr). All except one of the patients presented with pain, and 17 of 27 showed evidence of autonomic dysfunction at initial presentation. Based on microscopic examination of surgical specimen margins, surgical procedures were categorized as either radical resection or subtotal excision. All patients underwent at least one surgical procedure, for a total of 67 procedures (28 radical resections and 39 subtotal excisions). Twelve patients underwent one operation, whereas nine underwent two procedures and six underwent more than two operations (range, 3-16 operations). Radiation therapy was used in conjunction with 13 of the 67 surgical procedures. The median Kaplan-Meier estimate of the overall survival time for the entire group was 7.38 years (range, 4 mo to 34 yr). Tumors recurred after 47 of the 67 procedures. The overall disease-free interval for patients undergoing radical resection was 2.27 years for each procedure, compared with 8 months for each procedure for patients treated with subtotal excision (log-rank test for the inequality between the two curves, 19.58; P < 0.0001). The addition of radiation therapy prolonged the disease-free interval for patients undergoing subtotal resection (2.12 yr versus 8 mo; log-rank test for the inequality between the two curves, 5.82; P < 0.02). CONCLUSION: Our results suggest frequent recurrences in the majority of patients with chordomas. Radical resection is associated with a significantly longer disease-free interval, compared with subtotal removal of the tumor. Addition of radiation after subtotal resection improves the disease-free interval, although radiation therapy can generally be used only once. Based on these findings, we think that, whenever possible, radical resection should be the treatment of choice for sacral chordomas.
Scanning probe microscopies, nanoscience and nanotechnology

The symbiotic relationship between nanoscience and nanotechnology and the scanning probe microscopies is analyzed in terms of relating non-contact atomic force microscope (NC-AFM) technology to applications requiring detection, manipulation and fabrication on the molecular scale. The features of NC-AFM in this connection, which facilitate its unique relationship with nanoscale science and technology, are discussed. Specific typical examples are presented of applications where a NC-AFM measurement of a specific physical or chemical property is correlated with position, orientation or location on the atomic scale.
Dermatologic complications associated with administration of 2′,3′-dideoxycytidine in patients with human immunodeficiency virus infection

We describe a distinctive mucocutaneous eruption that occurred in 14 of 20 (70%) patients with human immunodeficiency virus infection while they were being treated with a new therapeutic agent, 2'3'-dideoxycytidine. A maculopapular eruption developed in these patients on day 10 or 11 of treatment. Seven of 14 patients, especially those receiving higher-dose therapy, also had systemic symptoms. In addition, oral ulcers developed in 9 of 14 patients on days 4 to 6 of therapy. The occurrence of the cutaneous and oral lesions correlated with dose, route, and schedule of administration of 2'3'-dideoxycytidine. In most instances the mucocutaneous lesions resolved even with continuation of therapy.
Studying the quality of life after organ transplantation : Research problems and solutions

Studies assessing the quality of life after organ transplantation proliferated in the 1980s after improved immunosuppression led to higher survival rates. Despite severe critiques of the methods employed in this research, as well as more general criticisms of the financial motives behind it, medical journals have continued to publish reports which almost uniformly conclude that transplant recipients enjoy a high quality of life. This paper revisits the critiques, asks why they have had so little impact, and suggests a new approach.
Some Recent Progresses in Network Error Correction Coding Theory

In this talk, we summarize some of our recent works on network error correction coding theory. Our works mainly focus on issues related to the goal of pushing the theory of network error correction coding to applications. In (Zhen Zhang, 2006), we define the minimum distance of a linear network error correction code and prove that it plays the same role as it does in classical coding theory, we propose the concept of statistical decoding and develop a statistical algorithm for decoding packet network error correction codes. In (S. Yang et al.), we study the characterization of network error correction capabilities in the general case which includes nonlinear codes. In (H. Bali et al., 2007), we propose an improved upper bound for the failure probability of random network code and use it to analyze the performance of randomized network error correction codes. In (X. Yan et al.), we study the possibility of decoding network error correction codes beyond its error correction capability, and analyze the decoding complexity of statistical decoding algorithms. In (H. Bali and Z. Zhang), we propose some techniques for reducing overhead of network error correction coding. This is a key issue for pushing network error correction codes to applications. In (Zhen Zhang), we propose a hybrid network error correction coding systems combining both the network error correction codes in the space domain and the classical error correction codes in the time domain and analyze its performance.
Retinoid Signaling Is Required to Complete the Vertebrate Cardiac Left/Right Asymmetry Pathway

Vitamin A-deficient (VAD) quail embryos have severe abnormalities, including a high incidence of reversed cardiac situs. Using this model we examined in vivo the physiological function of vitamin A in the left/right (L/R) cardiac asymmetry pathway. Molecular analysis reveals the expression of early asymmetry genes activin receptor IIa, sonic hedgehog, Caronte, Lefty-1, and Fgf8 to be unaffected by the lack of retinoids, while expression of the downstream genes nodal-related, snail-related (cSnR), and Pitx2 is altered. In VAD embryos nodal expression in left lateral plate mesoderm (LPM) is severely downregulated and the expression domain altered during neurulation. Similarly, the expression of cSnR in the right LPM and of Pitx2 in the left side posterior heart-forming region (HFR) is downregulated in the VAD embryos. The lack of retinoids does not cause randomization or ectopic expression of nodal, cSnR, or Pitx2. At the six- to eight-somite stage nodal is expressed transiently in the left posterior HFR of normal quail embryos; this expression is missing in VAD embryos and may be linked to the loss of Pitx2 expression in this region of VAD quail embryos. Administration of retinoids to VAD embryos prior to the six-somite stage rescues the expression of nodal, cSnR, and Pitx2 as well as the randomized VAD cardiac phenotype. There is an absolute requirement for retinoids at the four- to five-somite developmental window for cardiogenesis and cardiac L/R specification to proceed normally. We conclude that retinoids do not regulate the left/right-specific sidedness assignments for expression of genes on the vertebrate cardiac asymmetry pathway, but are required during neurulation for the maintenance of adequate levels of their expression and for the development of the posterior heart tube and a loopable heart. Cardiac asymmetry may be but one of several critical events regulated by retinoid signaling in the retinoid-sensitive developmental window.
Smart Hand For Manipulators

Sensor based, computer controlled end effectors for mechanical arms are receiving more and more attention in the robotics industry, because commonly available grippers are only adequate for simple pick and place tasks. This paper describes the current status of the research at JPL on a smart hand for a Puma 560 robot arm. The hand is a self contained, autonomous system, capable of executing high level commands from a supervisory computer. The mechanism consists of parallel fingers, powered by a DC motor, and controlled by a microprocessor embedded in the hand housing. Special sensors are integrated in the hand for measuring the grasp force of the fingers, and for measuring forces and torques applied between the arm and the surrounding environment. Fingers can be exercised under position, velocity and force control modes. The single-chip microcomputer in the hand executes the tasks of communication, data acquisition and sensor based motor control, with a sample cycle of 2 ms and a transmission rate of 9600 baud. The smart hand described in this paper represents a new development in the area of end effector design because of its multi-functionality and autonomy. It will also be a versatile test bed for experimenting with advanced control schemes for dexterous manipulation.
Role of an RNase III Binding Site in Transcription Termination at λ nutL by HK022 Nun Protein

The phage HK022 Nun protein excludes phage λ by binding nascent λ pL and pR transcripts at nutL and nutR, respectively, and inducing transcription termination just downstream of these sites. Termination is more efficient at nutL than at nutR. One difference between nutL and nutR is the presence of RNase III processing sites (rIII) located immediately promoter distal to λ nutL. We found that deletion of rIII dramatically reduced Nun transcription arrest in vitro but had little effect on termination in vivo. However, consistent with the in vitro results, overexpression of a transcript carrying nutL and rIII efficiently titrated Nun, allowing λ to grow on a strain that expressed Nun, whereas a transcript carrying only nutL or nutL-rIII with nucleotides 97 to 141 deleted was ineffective. Rnc70, an RNase III mutant that binds but does not cleave rIII, also prevented Nun-mediated λ exclusion. We propose that rIII enhances the on-rate of Nun at nutL, stimulating Nun-mediated arrest in vitro. We have shown that a specific element in rIII, i.e., box C (G89GUGUGUG), strongly enhances arrest on rIII+ templates. Nun-rIII interactions do not stimulate Nun termination in vivo, presumably because formation of the Nun-nutL complex is normally not rate-limiting in the cell. In contrast to Nun, N is not occluded by Rnc70 and is not efficiently titrated by a nutL-rIII transcript.
Review of the Molecular Development of the Thumb: Digit Primera

Background The thumb, or digit 1, is not a typical digit. In addition to its unusual mobility and function, its formation is also unusual. It is the last digit to form and the most commonly targeted when limb development is disrupted. The thumb domain is defined by the overlapping expression of HOXA13, TBX5, GLI3R, and HOXD13 and, importantly, by an absence of other distal HOXD transcription factors. This brief review, combining developmental biology and clinical genetics, discusses the current understanding of how the thumb domain is established.
Differentiating nonpoint sources of deisopropylatrazine in surface water using discrimination diagrams

Pesticide degradates account for a significant portion of the pesticide load in surface water. Because pesticides with similar structures may degrade to the same degradate, it is important to distinguish between different sources of parent compounds that have different regulatory and environmental implications. A discrimination diagram, which is a sample plot of chemical data that differentiates between different parent compounds, was used for the first time to distinguish whether sources other than atrazine (6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine) contributed the chlorinated degradate, deisopropylatrazine (DIA; 6-chloro-N-ethyl-1,3,5-triazine-2,4-diamine) to the Iroquois and Delaware Rivers. The concentration ratio of deisopropylatrazine to deethylatrazine [6-chloro-N-(1-methylethyl)1,3,5-triazine-2,4-diamine], called the D2R, was used to discriminate atrazine as a source of DIA from other parent sources, such as cyanazine (2-[[4-chloro-6-(ethylamino)-1,3,5-triazin-2-yl]amino]-2-methylpropionitrile) and simazine (6-chloro-N,N'-diethyl-1,3,5-triazine-2,4diamine). The ratio of atrazine to cyanazine (ACR) used in conjunction with the D2R showed that after atrazine, cyanazine was the main contributor of DIA in surface water. The D2R also showed that cyanazine, and to a much lesser extent simazine, contributed a considerable amount (approximately 40%) of the DIA that was transported during the flood of the Mississippi River in 1993. The D2R may continue to be a useful discriminator in determining changes in the nonpoint sources of DIA in surface water as cyanazine is currently being removed from the market.
On the Role of Upper Tropospheric Jet Streaks and Leeside Cyclogenesis in the Development of Low-Level Jets in the Great Plains

A review of 15 cases of low level jets (LLJ) which developed in the Great Plains is presented. For 12 out of the 15 cases, a systematic upper level flow pattern was isolated which includes the existence of a trough over the southwest United States and the propagation of upper level jet streaks from the Rocky Mountains toward the Great Plains. This flow pattern is responsible for lee side cyclogenesis or lee side troughing that produces the pressure gradients needed for the development of the LLJ. For the other three cases, a blocking ridge existed over the Great Plains and the upper level flow is relatively weak. It is during these situations that the classic, diurnal oscillating LLJ was observed. A more detailed review of four cases indicates that the subsynoptic scale adjustments associated with the upper level jet streak's forcing of lee side cyclogenesis could be an important factor in the development of LLJ's in the Great Plains.
A validation study of the Qiagen Investigator DIPplex® kit; an INDEL-based assay for human identification.

Marker sets that are based on small insertion/deletion (INDEL) alleles can serve as useful supplementary or stand-alone assays for human identification. A validation study has been performed on a human identification assay based on a panel of 30 INDELs and amelogenin using the Investigator DIPplex® kit (Qiagen). The assay was able to type DNA from a number of forensically relevant sample types and obtain full profiles with 62 pg of template DNA and partial profiles with as little as 16 pg of template DNA. The assay is reproducible, precise, and non-overlapping alleles from minor contributors were detectable in mixture analysis ranging from 6:1 to 19:1 mixtures. Population studies were performed on the 30 indels, and there were no significant departures from Hardy–Weinberg equilibrium or significant linkage disequilibrium between the markers (after correction for sampling). In all populations, the random match probability was 1.43 × 10−11 or less, and the power of exclusion was greater than .999999999. We also discovered several microvariant alleles in our population samples. The data support that the Investigator DIPplex® kit provides a powerful supplement or stand-alone capability for human identity testing.
The Growth Rate for the Number of Singular and Periodic Orbits for a Polygonal Billiard

For any simply connected polygon in the plane, the number of billiard orbits which begin and end at a vertex grows subexponentially with respect to the length or to the number of reflections. This implies that the numbers of isolated periodic orbits and of families of parallel periodic orbits do grow subexponentially. The main technical device is a calculation showing that the topological entropy of the Poincare map for the billiard flow is equal to zero.
Recognizing transcription start site (TSS) of plant promoters

Discovering a promoter or promoters from a given DNA sequence is an active research area in bioinformatics. Many promoter detection algorithms use transcription binding sights and some core promoter elements such as CCAAT and TATA box, to determine the location of transcription start site. For the purpose of comparing the effectiveness of different algorithms, we consider transcription start site in isolation. We use annotated plant promoters for our experiments. We have compared the following algorithms for their effectiveness in detecting a TSS: position weighted matrix (PWM), naive Bayes, decision tree and artificial neural network.
Large-scale and highly efficient synthesis of micro- and nano-fibers with controlled fiber morphology by centrifugal jet spinning for tissue regeneration.

PLLA fibrous tissue scaffolds with controlled fiber nanoscale surface roughness are fabricated with a novel centrifugal jet spinning process. The centrifugal jet spinning technique is a highly efficient synthesis method for micron- to nano-sized fibers with a production rate up to 0.5 g min−1. During the centrifugal jet spinning process, a polymer solution jet is stretched by the centrifugal force of a rotating chamber. By engineering the rheological properties of the polymer solution, solvent evaporation rate and centrifugal force that are applied on the solution jet, polyvinylpyrrolidone (PVP) and poly(L-lactic acid) (PLLA) composite fibers with various diameters are fabricated. Viscosity measurements of polymer solutions allowed us to determine critical polymer chain entanglement limits that allow the generation of continuous fiber as opposed to beads or beaded fibers. Above a critical concentration at which polymer chains are partially or fully entangled, lower polymer concentrations and higher centrifugal forces resulted in thinner fibers. Etching of PVP from the PLLA–PVP composite fibers doped with increasing PVP concentrations yielded PLLA fibers with increasing nano-scale surface roughness and porosity, which increased the fiber hydrophilicity dramatically. Scanning electron micrographs of the etched composite fibers suggest that PVP and PLLA were co-contiguously phase separated within the composite fibers during spinning and nano-scale roughness features were created after the partial etching of PVP. To study the tissue regeneration efficacy of the engineered PLLA fiber matrix, human dermal fibroblasts are used to simulate partial skin graft. Fibers with increased PLLA surface roughness and porosity demonstrated a trend towards higher cell attachment and proliferation.
The ribonucleic acid of Epanaphe moloneyi Druce.

Abstract Larvae of the moth Epanaphe moloneyi Druce secrete a silk fibroin whose composition is virtually alanine and glycine in equimolar amounts. We have analyzed the base composition of the ribonucleic acid of the fibroin secreting portion of the silk gland and compared it with ribonucleic acid from the sericin secreting portion, larval gut and adult whole body. No statistically significant differences were found. We discuss the hypothesis that the major part of the RNA is not organ specific and that its composition is not correlated with the composition of the protein being synthesized.
Experimental study of co-annular jet subjected to transverse disturbances

Abstract The results of an investigation of the flow field of two coaxially aligned jets consisting of an inner primary jet and a co-annular outer jet issuing from a nozzle with convex sidewalls are reported. A transverse flow injection into the co-annular jet was used to shape the co-annular jet flow. In the region between the exits of the two jets, a recirculating toroidal eddy is formed due to opposing pressure gradients. In the presence of transverse injection, the eddy bifurcates into two lobes with radially emanating flow structures that substantially increase the decay of axial velocity and the spread rate to twice the values when compared to the characteristics of the primary jet alone. Measurements of mean velocities and Reynolds stresses were made at the jet Reynolds number of 16,000 with the help of a specially designed two-component Laser-Doppler-Velocimetry system. Topology of the resulting complex flow in view of the measurements is presented and discussed.
Internal sequence analysis of proteins eluted from polyacrylamide gels.

We have developed an elution-digestion-sequencing (EDS) method, which yields the internal amino acid sequence of partially purified proteins. The overall yield for the method was greater than 60%. The method yielded peptide peaks that could be sequenced on HPLC for all tested proteins with masses from 45 to 200·103 and yielded internal amino acid sequence information when as little as 10 pmol of partially purified protein was used as the starting material. The EDS method was extremely reliable and gave sequence information for each of 25 proteins tested, including high-molecular-mass proteins (Mr>100·103) that were difficult to sequence by other methods.
Promising to Try

We maintain that in many contexts promising to try is expressive of responsibility as a promiser. This morally significant application of promising to try speaks in favor of the view that responsible promisers favor evidentialism about promises. Contra Berislav Marusic, we contend that responsible promisers typically withdraw from promising to act and instead promise to try, in circumstances in which they recognize that there is a significant chance that they will not succeed.
Entrepreneurial Women and the Business of Self-Development in Global Russia

AbstractA 2007 survey indicated that Russia was the only country in the world where more women than men actively sought to start their own businesses. In a social context of significant gendered inequalities in the labor force, many educated women perceived business management as a path to upward socioeconomic mobility and self-development (samorazvitie). To be a businesswoman in President Vladimir’s Russia was not easy, however; it meant going against the grain of cultural assumptions that “normal” women strove to become mothers and wives. Women who headed their own firms often faced difficulties finding spouses, professional partners, and friends who respected them and their social contributions. Based on ethnographic fieldwork with urban managerial women in a variety of commercial sectors, this article asks: how did these women make sense of their place in Russian society? Rather than attempt to alter gendered social and economic inequalities, women focused on changing their own self-perceptions and co...
Six Randomized Evaluations of Microcredit: Introduction and Further Steps †

Causal evidence on microcredit impacts informs theory, practice, and debates about its effectiveness as a development tool. The six randomized evaluations in this volume use a variety of sampling, data collection, experimental design, and econometric strategies to identify causal effects of expanded access to microcredit on bor rowers and/or communities. These methods are deployed across an impressive range of locations—six countries on four continents, urban and rural areas—borrower characteristics, loan character istics, and lender characteristics. Summarizing and interpreting results across studies, we note a consistent pattern of modestly positive, but not transformative, effects. We also discuss directions for future research. (JEL D14, G21, I38, O15, O16, P34, P36)
Chlordecone pretreatment alters [14C]chlordecone and [14C]cholesterol transport kinetics in the perfused rat liver.

Abstract Chlordecone Pretreatment Alter [14C]Chlordecone and [14C]Cholesterol Transport Kinetics in the Perfused Rat Liver. Gilroy, D. J., Carpenter, H. M., and Curtis, L. R. (1994). Fundam. Appl. Toxicol. 22, 286-292. Previous work demonstrated that pretreatment of mice with low doses of the organochlorine insecticide chlordecone (CD) altered the tissue disposition of a subsequent [14C]CD or [14C]cholesterol challenge dose. The profile of these changes was consistent with the induction of a protein integral to hepatic CD/cholesterol turnover. The present study was undertaken to confirm similar in vivo effects in the rat and to analyze potential CD-induced changes in hepatic transport kinetics in the perfused rat liver. For in vivo experiments, male Sprague-Dawley rats were treated with CD (5, 15, or 40 mg/kg) and challenged 3 or 7 days later with a 5 mg/kg [14C]CD tracer dose. Rats challenged 3 days after treatment and evaluated 16 hr later showed a dose-dependent decrease in hepatic [14C]CD relative to controls. This decrease could not be attributed to alterations in liver mass or total liver lipid. For kinetics studies, rats received 15 mg/kg CD and livers were perfused 3 days later. Following a brief (5-7 min) single-pass perfusion, the perfusate was replaced with recirculating buffer containing albumin-bound [3H]oleic acid or high-density lipoprotein-bound [14C]CD or [14C]cholesterol. Livers from pretreated animals had significantly decreased rates of [14C]CD and [14C]cholesterol uptake. Efflux of [14C]CD and biliary excretion of [14C]cholesterol were increased. No changes were observed in uptake or biliary excretion of [3H]oleic acid. SDS-PAGE of hepatic cytosol revealed an enhanced band intensity corresponding to a Mr of 25,600 in livers from pretreated rat. These results are supportive of a competitive interaction between cholesterol and CD for proteins associated with hepatocellular transport and excretion and suggest that CD pretreatment may have an inductive effect on these proteins.
A REMARKABLE PIPE FROM NORTHWESTERN AMERICA

This pipe, which is tubular in form and of the very remarkable length of 266 mm., is of mottled bluish-green steatite, apparently identical in character with that of which similar specimens of this type are made. The bowl of the pipe, which measures 53 mm. in length and forms a slight angle at its junction with the stem, is of the form characteristic of pipes of the Thompson River region.' Its upper edge is cut squarely across, while the bowl itself is gouged out longitudinally, in the process of which the wall in one place was broken through. The bowl is not circular, varying in diameter from I8 to 20 mm.
Scavenger studies of electron pulse irradiated solutions at hydrated electron half lives in the range 35-0·35 nanoseconds

Abstract In general hydrated electron rate constants are measured with pulsed electron beams at solute concentrations of less than 10−4 mol dm−3 when the rate constants is of the order of 1010 dm3 mol−1 s−1. We have employed a sensitive technique for determining rate constants at concentrations where the eaq- half-life approaches 0·35 ns during the pulse and its steady-state concentration is about 5 × 10−7 mol dm−3. A conventional kinetic spectrophotometric apparatus is used with an electronic averaging device which integrates the area under the absorption signal during a train of 3 μs electron pulses. After corrections for Cerenkov emission, the area measured is proportional to Gϵ/kc where G is the yield of eaq-; ϵ is the molar extinction coefficient of eaq-; k is the rate constant for the reaction eaq-+solute; and c is the solute concentration. In the concentration range 10−4–10−1 mol dm−3 HCLO4, the quantity k/G decreases with increasing concentration. By correcting the known values of k and G respectively for the decreasing effect of ionic strength and increasing effect of H+ concentration in the spurs according to the one-radical model of Flanders and Fricke (J. chem. Phys. 1958, 28, 1126), k/G calculated and experimental are in fairly good agreement. This is equally true for N2O and CH3Cl where there is no effect of ionic strength. On the contrary, for (CH3)2SO (DMSO) as solute up to 3·5 mol dm−3, where no ionic strength correction is required and corrections of G are negligible (rate constant of eaq- with DMSO = 1·6 × 106 dm3 mol−1 s−1), k/G increases with solute concentration, which corresponds to a decrease in G. This result seems to indicate that unhydrated electrons are scavenged by DMSO before hydration occurs.
4. MATERNAL HEMODYNAMIC CHANGES AND FETAL GROWTH RETARDATION

Based on previous studies we have postulated that blood volume expansion during pregnancy is a key physiological adjustment since it makes possible the ircrease in cardiac output and utero-placental blood flow, necessary to sustain normal fetal growth. This idea was tested in non-smoking, non-hipertensive gravidas who by ultrasound scanning were found to carry either a normal size fetus (“control”) (15 cases) or a small-for-date fetus (“experimental”) (15 cases). At weeks 37 - 43 of gestation measurements of plasma volume, using the Evans blue method, and cardiac output, using eohocardiography, were performed in all subjects while in a left lateral position. At delivery the newborns were examined to establish adequacy of weight for gestacional age and to rule out congenital malformations ard infections. Plasma volume was 3120 ± 484 (S.D) ml in controls and 2717 ± 217 ml in experimentals (p <0.01). Cardiac output was 6127 ± 868 ml/min in controls and 5282 ± 891 ml/min in experimentals (p<0.01). In both groups combined plasma volume was significantly correlated with cardiac output (r= 0.45; p<0.01) ard both plasma volume and cardiac output were significantly correlated with birth weight (r= 0.47; p < 0.01 ard r=0.42; p<0.01, respectively). The data support the hypothesis that inadecuate maternal plasma volume expansion my lead to fetal growth retardation. (Supported by grant 116/85 from the Direction de Investigacion, Universidad Catolica de Chile).
The Utility of Multilevel Modeling vs. Agent-Based Modeling in Examining Spatial Disparities in Diet and Health: The Case of Food Deserts

From a policy perspective, the presence and persistence of food deserts and the subsequent diet and health effects on those living in such areas pose a modeling conundrum. Should the deserts be the focus of attention where the modeling effort is on identifying the interactions and interdependencies across space and time that contribute to their creation, or should one focus on the consequences of lack of access to food and attempt to explore the adverse nutrition and health outcomes that can be attributed to such deserts? Attempting to address these questions requires not only different conceptual models but also different data models. To that end, we offer to compare and contrast the utility of using multilevel regression modeling vs. agent-based modeling in examining spatial disparities in health, specifically looking at how each type of model can address these aforementioned questions. The primary purpose of this chapter is to give emphasis to the value of operational thinking in model design and encourage building conceptual and data models that are more useful to policymakers when proposing policy interventions.
Advances in the Management of Non‐seminomatous Germinal Tumours of the Testis

Experience in the management of 146 consecutive patients with non-seminomatous tumours of the testis has led to a plan of management based on retroperitoneal lymph node dissection as the primary treatment modality, with use of adjuvant therapy dependent on pathological findings. Chemotherapy has proved to be the most important adjuvant with postoperative radiation therapy reserved only for patients with extensive retroperitoneal metastatic disease. 3-year crude survival for patients with all stages of disease was 78% and in those in whom the disease was confined to below the diaphragm the survival rate was 85%.
Ecdysteroids and a sucrose phenylpropanoid ester from Froelichia floridana

Abstract Phytoecdysteroid glycosides (1–5) and a phenylpropanoid ester of sucrose (6) were isolated from the whole plant of Froelichia floridana, along with eight known compounds including three ecdysteroids (7–9), four flavonoids (10–13), and one phenolic compound (14). Structures were determined using a combination of spectroscopic techniques. Compounds 1, 2 and 6–14 were tested in vitro for their activity against human DNA topoisomerase I. Compound 13 (diosmetin) showed marginal inhibition against topoisomerase I with IC50 of 130 μM in conjunction with low intercalation ability.
Reengineering the requirements process for executive support system development using an electronic meeting system

The gathering of requirements for the development of executive support systems and computerized patient records has proven to be a time-consuming and challenging process. This paper presents an example of practice involving the end users and their support team, in a technology-assisted process of requirements determination. The participants utilized an electronic meeting system with a process designed to collect system requirements in a group setting. Three institutions participated in the testing and validation of this process. A panel of experienced executive support system implementers reviewed the process and findings for effectiveness relative to previous experience. Subsequently, the technology and process has been expanded to successfully collect the general requirements for a computer-based patient record system for one of the sites. >
Chapter Seven: Past, Present, and Future

Meaning-Oriented Studies, p.414 Acquisitional Sequences, p.418 Aspect Studies, p.423 Discourse Studies, p.430 The Influence of Instruction, p.432 Concluding Remarks, p.435
SIMS analysis of volatiles in silicate glasses:: 1. Calibration, matrix effects and comparisons with FTIR

This paper describes microanalysis techniques using secondary ion mass spectrometry (SIMS) to measure the abundances and isotopic compositions of hydrogen, carbon, fluorine, sulfur and chlorine in volcanic glasses. SIMS measurement of total H_2O and total CO_2 abundances compare very well with measurements on the same glasses using vibrational spectroscopy techniques (FTIR). A typical 10-min SIMS measurement for volatile abundances is made on a singly polished specimen, sputtering a crater 15–30 μm in diameter and 2–3 μm deep, utilizing 1–5×10^(−9) g of sample material. Detection limits are routinely <30 ppm H_2O, <3 ppm CO_2, and <1 ppm F, S and Cl. Measurements of δD, δ^(13)C and δ^(34)S in volcanic glasses are currently reproducible and accurate to 2–5‰, depending on the concentration of the element. Because of their spatial selectivity, the SIMS methods allow resolution of magmatic volatile signatures from those carried by secondary phases, which can sometimes plague traditional vacuum extraction methods that require large amounts of sample (tens to hundreds of milligrams). Ease of sample preparation, rapid analysis and high sensitivity allow SIMS to be applied to volatile analysis of small samples such as melt inclusions, in which large numbers of individual analyses are often required in order to obtain a representative sample population. Combined abundance and isotopic composition data for volatile elements provide coupled constraints on processes relevant to magma genesis and evolution, including degassing, magma contamination, mixing, and source variability.
LIFE-CYCLE ASSESSMENT OF NET GREENHOUSE-GAS FLUX FOR BIOENERGY CROPPING SYSTEMS

Bioenergy cropping systems could help offset greenhouse gas emissions, but quantifying that offset is complex. Bioenergy crops offset carbon dioxide emissions by converting atmospheric CO2 to organic C in crop biomass and soil, but they also emit nitrous oxide and vary in their effects on soil oxidation of methane. Growing the crops requires energy (e.g., to operate farm machinery, produce inputs such as fertilizer) and so does converting the harvested product to usable fuels (feedstock conversion efficiency). The objective of this study was to quantify all these factors to determine the net effect of several bioenergy cropping systems on greenhouse-gas (GHG) emissions. We used the DAYCENT biogeochemistry model to assess soil GHG fluxes and biomass yields for corn, soybean, alfalfa, hybrid poplar, reed canarygrass, and switchgrass as bioenergy crops in Pennsylvania, USA. DAYCENT results were combined with estimates of fossil fuels used to provide farm inputs and operate agricultural machinery and fossil-fuel offsets from biomass yields to calculate net GHG fluxes for each cropping system considered. Displaced fossil fuel was the largest GHG sink, followed by soil carbon sequestration. N2O emissions were the largest GHG source. All cropping systems considered provided net GHG sinks, even when soil C was assumed to reach a new steady state and C sequestration in soil was not counted. Hybrid poplar and switchgrass provided the largest net GHG sinks, .200 g CO2e-Cm � 2 � yr � 1 for biomass conversion to ethanol, and .400 g CO2e-Cm � 2 � yr � 1 for biomass gasification for electricity generation. Compared with the life cycle of gasoline and diesel, ethanol and biodiesel from corn rotations reduced GHG emissions by ;40%, reed canarygrass by ;85%, and switchgrass and hybrid poplar by ;115%.
Neural control of smart electromagnetic structures

Artificial neural networks (ANNs) and their ability to model and control dynamical systems for smart structures, including sensors, actuators, and plants, are directly applicable to the smart electromagnetic structures (SEMS) concept. The application of neural networks to the area of controls is being reported frequently. The ability of a structure to adapt to impinging electromagnetic (EM) energy will allow the structure to change its reflection characteristics and thus to change its radar signature. By embedding a control element in the structure of a single microstrip patch element, its electrical characteristics can be changed. If such an element can be controlled by a closed loop system the patch antenna element can be made to adjust its operating characteristics through the control algorithm. If the control algorithm can be implemented in a neural network, the system can be made to change its characteristics in response to the stimulus. This change can be used to alter the antenna's performance in real time. As part of our research, a model of the patch neural network antenna system is being developed and this analytical model, as well as experimental models of the antenna are being tested and compared. The neural network antenna model and prototypes are being taught to adapt to the magnitude and phase response of microstrip patch antennas to incoming signals. The response characteristics and speed are reported in this paper. We demonstrate that the patch can be given autonomous adaptive capabilities using neural networks. An array of such smart patches could be assembled to create an even more adaptable antenna system.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Analysis of time-dependent cylindrical problems using Monte Carlo

Monte Carlo method is well known for solving static problems such as Laplace's or Poisson's equation. In this article, we extend the applicability of the conventional Monte Carlo method to solve time-dependent cylindrical problems. We present results in one-dimensional and two-dimensional regions that agree with the exact solutions. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2571–2573, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22790
System Identification Using Frequency Scanning and the Eigensystem Realization Algorithm

The application of the eigensystem realization algorithm to flexible structures excited with nonimpulse r type inputs is described. Sinusoidal pulses are a special subset of such inputs, and a discussion is given r. on their use to lock on to particular modes. The determination of impulse response functions from N) nonimpulse response functions is performed via a two step procedure. In the first step, free decay data is analyzed by the eigensystem realization algorithm to determine the structural frequencies and damping. "C:3 ammo Forced response data is analyzed in the second step, by solving an overdetermined set of linear equations - ,": for the modal coefficients of the impulse responses. It is shown that the number of impulse response % ~ coefficients is halved if displacement, velocity, and/or acceleration sensors are used in conjunction with) force actuators. System identification is completed after the eigensystem realization algorithm is used on the impulse responses to produce a linear state space model of the structure. Numerical examples are given in which structural models are determined from simulated data corrupted with noise.
Accounting for the Unaccounted: Weak-Actor Social Structure in Asymmetric Wars

This paper addresses a puzzle of how conflicts characterized by significant power asymmetries often play out much differently than dominant powers expect. We adapt the notions of institutionalized peace and riot systems from the literature on ethnic violence to identify ways in which social institutions attenuate collective action dilemmas, thereby increasing capability for a less-powerful group. Dominant groups often miscalculate the true nature of capability relationships by failing to account for these group-specific institutions that operate in the face of exogenous threats. We illustrate our model with two episodes of Chechen mobilization in the 1990s.
Speculations on the Earth's Thermal History

The gross structure of the Earth's interior—mantle and core with their subdivisions—affords evidence of the thermal evolution. The principal event was the formation of a liquid iron core from an initially cool unsorted conglomerate after about 500 m.y. of heating by radioactivity and tidal friction. Core formation was accompanied by conversion of gravitational energy to heat, the deep interior reaching temperatures of 4000°–5000°; this process was completed about 4500 m.y. ago. Fractional melting of the mantle concentrated radioactive and “lithophile” elements in the upper mantle and transition zone, leaving the lower mantle devoid of radioactivity. Formation of stable continental crust became possible after this upward concentration and decay of radioactivity, beginning about 3500 m.y. ago. Further concentration of the radioactive elements in the continental crust has left the subcontinental mantle impoverished by comparison with the suboceanic mantle. Present temperatures are consequently higher in the suboceanic mantle than at the same depths beneath continents, approaching or reaching melting temperatures beneath the oceans while cooling continues beneath continents. The required concentrations of radioactive elements appear to be in reasonable agreement with existing measurements if the primitive undifferentiated Earth resembled the meteorite Orgueil in its radioactive content.
Quality of life and social integration after allogeneic hematopoietic SCT

In total, 124 adult patients in remission after allogeneic hematopoietic SCT (HSCT) participated in a cross-sectional study to assess health-related quality of life (HRQL). Assessment of HRQL was carried out using two questionnaires: the (EORTC QLQ-C30) and the Functional Assessment of Cancer Therapy (FACT) with specific modules for BMT (FACT-BMT). Transplanted patients differed from healthy controls in many HRQL-related dimensions in the EORTC QLQ-C30: social functioning 73.4 versus 85.8, P<0.0001; role functioning 74.6 versus 83.3, P<0.004; physical functioning 83.9 versus 89.9, P<0.001; emotional functioning 72.2 versus 82.8, P<0.0001 but were not significant for global HRQL 71.2 versus 75.3, P<0.03. In total, 60% of the patients returned to work after HSCT; 31% part time and 29% full time. Age at HSCT and employment status were significantly associated with HRQL. Other factors such as disease and disease stage and especially the occurrence of late complications did not impact the perception of HRQL. This study suggests that the perception of HRQL after HSCT differs from the general population. Issues to increase work-related capabilities and improve social support need to be addressed.
Gated Diffusion-controlled Reactions

The binding and active sites of proteins are often dynamically occluded by motion of the nearby polypeptide. A variety of theoretical and computational methods have been developed to predict rates of ligand binding and reactivity in such cases. Two general approaches exist, "protein centric" approaches that explicitly treat only the protein target, and more detailed dynamical simulation approaches in which target and ligand are both treated explicitly. This mini-review describes recent work in this area and some of the biological implications.
Voltage comparators implemented with GaAs/(GaAl)As heterojunction bipolar transistors

The first voltage comparators implemented with GaAs/(GaAl)As heterojunction bipolar transistors (HBTs) are reported. The offset voltage of these circuits was found to be generally below 4 mV, and hysteresis below 1 mV; both voltages stayed quite constant over a range of reference voltage of about 1 V. The preliminary circuit yield was high. This work demonstrated the suitability of these HBT comparators for use in a flash A/D convertor of high accuracy (up to 8 bits).
Transformation between the EMYCIN Model and the Bayesian Network

If different expert systems use different uncertain reasoning models in a distributed expert system, it is necessary to transform the uncertainty of a proposition from one model to another when they cooperate to solve problems. This paper looks at ways to transform uncertainties between the EMYCIN model and the Bayesian network. In the past, the uncertainty management scheme employed the most extensively in expert systems was the EMYCIN model. Now the scheme is turning towards the Bayesian network. If we can combine, by means of the Internet, pre-existing stand-alone expert systems that use these two models into a distributed expert system, the ability of these individual expert systems in their real applications will be greatly improved. The work described in this paper is an important step in this direction.
Women and AIDS.

The number and proportion of women infected with the human immunodeficiency virus (HIV) and with the acquired immunodeficiency syndrome (AIDS) have increased rapidly throughout the last decade. Despite these increases, the scientific community has focused limited research attention on women living with HIV infection. Data from studies of predominantly gay/bisexual men may not reliably be extended to women; studies of the natural history of HIV infection in women are needed. Obstetrician-gynaecologists are increasingly called upon to diagnose HIV infection in women and provide care in both clinical and research settings. In this review we discuss the serodiagnosis of HIV infection in women; the impact of pregnancy on HIV disease progression; transmission of HIV infection from mother to offspring; gynaecological infections and malignancies which may manifest differently in HIV-infected women; and clinical care of women living with HIV.
Characterization and Quantitation of Benzo[A]pyrene-DNA Adducts by Solid-Matrix Luminescence

Abstract Benzo[a]pyrene(B[a]P)-DNA adducts were modified at a level of 2.6%, and both the solid-matrix fluorescence (SMF) and solid-matrix phosphorescence (SMP) properties of the adducts were compared on Whatman 1PS paper, Whatman 1PS paper with T1NO3, and 30% T1NO3/sodium acetate (NaOAc). The quantitative aspects of determining B[a]P-DNA adducts with different quantities of the 2.6% modified B[a]P adduct samples were explored by comparing the SMF and SMP on these solid matrices. Calibration curves and limits of detection were acquired with SMF for the B[a]P-DNA adducts adsorbed on the three solid matrices. It was found that the SMP of B[a]P-DNA adducts on 30% T1NO3/NaOAc was more intense than both the SMF and the SMP of adducts adsorbed on Whatman 1PS paper. A typical linear range for the adducts on 30% T1NO3/NaOAc was 0 to 1.0 ng of adduct sample per mg of 30% T1NO3/NaOAc with a limit of detection of 0.06 ng of B[a]P-DNA adduct per mg of 30% T1NO3/NaOAc. In terms of molar concentration, the limit of det...