cssi/SciSciGPT-SciSciNet huggingface dataset:
Dermatologists and antibiotic prophylaxis: A survey☆

Abstract Background: Antibiotic prophylaxis is frequently used for the prevention of infection at a distant site such as the heart valve or prosthetic joint. However, there are no published data describing how dermatologists manage patients "at risk". Objective: The purpose of this study is to document prophylactic antibiotic use by dermatologists. Methods: A total of 211 randomly selected community dermatologists and 69 academic dermatologic surgeons were surveyed by questionnaire to determine whether they would provide antibiotic prophylaxis in 20 different clinical situations. Results: This survey showed that under certain circumstances, almost all dermatologists provide antibiotic prophylaxis to prevent infection at a distant site. However, many dermatologists use antibiotics in settings with relatively little or no indication and confuse a prophylactic regimen with treatment of a superficial infection. Conclusion: This survey underscores the need for education and research into the prophylactic management of patients "at risk" who undergo dermatologic surgical procedures.
Akt-mediated GSK-3β inhibition prevents migration of polyamine-depleted intestinal epithelial cells via Rac1

The rapid migration of intestinal epithelial cells (IEC) is important for the healing of mucosal wounds. We have previously shown that polyamine depletion inhibits migration of IEC-6 cells. Akt activation and its downstream target GSK-3β have been implicated in the regulation of migration. Here we investigated the significance of elevated phosphatidylinositol 3-kinase (PI3K)/Akt signaling on migration of polyamine-depleted cells. Polyamine-depleted cells had high Akt (Ser473) and GSK-3β (Ser9) phosphorylation. Pretreatment with 20 μM LY294002 (PI3K inhibitor) for 30 min inhibited phosphorylation of Akt, increased migration by activating Rac1 in polyamine-depleted IEC-6 cells, and restored the actin structure similar to that in cells grown in control medium. Treatment of cells with a GSK-3β inhibitor (AR-A014418) altered the actin cytoskeleton and inhibited migration, mimicking the effects of polyamine depletion. Thus, our results indicate that sustained activation of Akt in response to polyamine depletion inhibits migration through GSK-3β and Rac1.
Imagery super-resolution: emerging prospects

The problem of Image Super-Resolution is defined as processing an image in such a way as to extend the bandwidth of the image beyond the diffraction-limited spatial frequency imposed by the optical aperture forming the image. We present an algorithm which is derived by MAP estimation under Poisson modelling assumptions. The algorithm has been demonstrated empirically as capable of producing Super-Resolution. We hypothesize that the modelling process is responsible for adding additional information that constitutes the potential for image bandwidth extension. We outline an information theory analysis to quantify the modelling information, and indicate the forthcoming efforts to be conducted in pursuit of this analysis.
Rat C6 Glial Cells Synthesize Insulin-Like Growth Factor I (IGF-I) and Express IGF-I Receptors and IGF-II/ Mannose 6-Phosphate Receptors*

We have used the rat C6 glial cell line as a model system to study the role of insulin-like growth factors (IGF) in neuroglial cells of the central nervous system (CNS). Northern blot analysis of C6 RNA demonstrated the presence of IGF-I mRNA and undetectable IGF-II mRNA. IGF-I and IGF-binding protein (s), but not IGF-II, were detected in C6 glial cell-conditioned medium. The level of IGF-I was 1-4 ng/ml in conditioned medium based on a human IGF-I standard. The immunoreactive IGF-I inhibited [125I] IGF-I binding to the IGF-I receptor on chick embryo fibroblasts and stimulated [3H] thymidine incorporation into chick embryo fibroblast DNA. Competitive binding and affinity cross-linking experiments using [125]IGF-I and [125I] IGF-II demonstrated the presence of IGF-I receptors (type I) and IGF-II/mannose 6-phosphate receptors (type II) on C6 glial cell membranes. An immunoglobulin (no. 3637) directed against the rat IGF-II receptor blocked the degradation of [125I]IGF-II added to C6 glial cells, presumably ...
Kinetic and Structural Characterization of Human Mortalin

Human mortalin is an Hsp70 chaperone that has been implicated in cancer, Alzheimer's and Parkinson's disease, and involvement has been suggested in cellular iron-sulfur cluster biosynthesis. However, study of this important human chaperone has been hampered by a lack of active material sufficient for biochemical characterization. Herein, we report the successful purification and characterization of recombinant human mortalin in Escherichia coli. The recombinant protein was expressed in the form of inclusion bodies and purified by Ni-NTA affinity chromatography. The subsequently refolded protein was confirmed to be active by its ATPase activity, a characteristic blue-shift in the fluorescence emission maximum following the addition of ATP, and its ability to bind to a likely physiological substrate. Single turnover kinetic experiments of mortalin were performed and compared with another Hsp70 chaperone, Thermotoga maritima DnaK; with each exhibiting slow ATP turnover rates. Secondary structures for both chaperones were similar by circular dichroism criteria. This work describes an approach to functional expression of human mortalin that provides sufficient material for detailed structure-function studies of this important Hsp70 chaperone.
Origin and evolution of LINE-1 derived "half-L1" retrotransposons (HAL1).

LINE-1 (L1) retrotransposons represent the most abundant family of non-LTR retrotransposons in virtually all mammals. The only currently known exception is Platypus, where it is found only in low copy numbers. Autonomous L1s encode two proteins, ORF1p and ORF2p, both of which are required for the transposition of L1s. L1 replicative machinery is also involved in the trans-mobilization of non-autonomous retrotransposons, such as diverse short interspersed repetitive elements (SINEs) and processed pseudogenes. Here, we focus on a unique category of “half -L1” elements (HAL1s), which encode ORF1p but not ORF2p. HAL1s are present both in placental mammals and marsupials. We demonstrate that HAL1s originated independently several times during the evolution of mammals. The youngest mammalian HAL1 elements analyzed in this paper were identified in the guinea pig genome. Our analysis strongly suggests that HAL1-encoded ORF1p is essential for the transposition of HAL1s and indicates that the evolution of ORF1p in HAL1s is faster than in L1s. The implications of HAL1 for the evolution of L1 elements and the host genomes are discussed.
Mechanism of Proton-Coupled Electron Transfer for Quinone (QB) Reduction in Reaction Centers of Rb. Sphaeroides

The mechanism of the proton-coupled electron transfer reaction, + H+ → QA(QBH)- was studied in reaction centers (RCs) from the photosynthetic bacterium Rb. sphaeroides by substituting quinones with different redox potentials into the QA site. These substitutions change the driving force for electron transfer without affecting proton transfer rates or proton binding equilibria around the QB site. The measured rate constants, increased with increasing electron driving force (by a factor of 10 per 160 meV change in redox free energy). The proton-coupled electron transfer was modeled by (i) four possible two-step mechanisms in which electron transfer can precede or follow proton transfer and can be either the rate determining or fast step in the overall reaction and (ii) a one-step mechanism involving the concerted transfer of an electron and a proton. The free energy dependencies of these possible mechanisms were predicted using Marcus theory and were compared to the observed dependence. The two stepwise mec...
The Role of Leading-Edge Contouring on End-Wall Flow and Heat Transfer: Computations and Experiments

Numerical predictions and measurements of the flow structure and the Nusselt number behavior are presented for the endwall region of a linear blade cascade with contoured leading edge fillets. Two types of fillet profiles are employed: (a) a linear profile and (b) a circular profile. The fillets are placed at the junction of the blade leading edge and bottom endwall. The results with the fillets are also compared with the baseline case (predicted and measured) without any leading edge fillet. The pitchwise pressure gradient and shear stress on the endwall region are reduced for the filleted blades compared to the baseline case where there is no fillet. The flow turning from the axial direction (yaw angle) and the pitchwise flow velocity at the endwall boundary layer are also reduced in the vicinity of the fillets. In addition, the fillets weaken the leading edge horseshoe vortex by significantly reducing its vorticity and turbulent kinetic energy. Because of such changes in the endwall boundary layer, especially in the region where the fillets are located, the streamwise vorticity, turbulence kinetic energy, and total pressure losses in the passage vortex and the suction side leg vortex are reduced compared to the baseline. Endwall Nusselt numbers for the filleted cases are reduced upstream of the throat region.Copyright © 2006 by ASME
Rubisco without the Calvin cycle improves the carbon efficiency of developing green seeds

Efficient storage of carbon in seeds is crucial to plant fitness and to agricultural productivity. Oil is a major reserve material in most seeds1, and these oils provide the largest source of renewable reduced carbon chains available from nature. However, the conversion of carbohydrate to oil through glycolysis results in the loss of one-third of the carbon as CO2. Here we show that, in developing embryos of Brassica napus L. (oilseed rape), Rubisco (ribulose 1,5-bisphosphate carboxylase/oxygenase) acts without the Calvin cycle2 and in a previously undescribed metabolic context to increase the efficiency of carbon use during the formation of oil. In comparison with glycolysis, the metabolic conversion we describe provides 20% more acetyl-CoA for fatty-acid synthesis and results in 40% less loss of carbon as CO2. Our conclusions are based on measurements of mass balance, enzyme activity and stable isotope labelling, as well as an analysis of elementary flux modes.
Centripetal Sequence of Appearance of Receptor–Bipolar Synaptic Structures in Developing Mouse Retina

VISUALIZATION of layering phenomena in several light microscopic studies1–5 has given rise to the view that the retina matures morphologically in a centrifugal sequence from inner to outer layers, with ganglion cells maturing first and receptors last6. On the other hand, in a variety of species (mouse7, rat8, rabbit2, dog9, chick10 and frog11) in which the order of appearance of light-evoked electroretinographic wave forms has been followed through the developmental period, the a-wave, which is believed to arise at an outer retinal level12,13, could be elicited several days earlier than the b-wave which is believed to arise at an inner retinal level14–16. A centripetal sequence of at least certain aspects of functional maturation, from outer to inner levels of the retina, is suggested by these data.
Robot reachability problem: A nonlinear optimization approach

The reachability of a robot manipulator to a target is defined as its ability to move its joints and links in free space in order for its hand to reach the given target. This paper presents a way of testing the reachability of a robot to given target. The target could be a three dimensional object represented by a cuboid, a line or merely a point.
Cloning of cDNA and Genomic DNA Encoding Human Type XVIII Collagen and Localization of the α1(XVIII) Collagen Gene to Mouse Chromosome 10 and Human Chromosome 21

Abstract Types XV and XVIII collagen belong to a unique and novel subclass of the collagen superfamily for which we have proposed the name the MULTIPLEXIN family. Members of this class contain polypeptides with multiple triple-helical domains separated and flanked by non-triple-helical regions. In this paper, we report the isolation of human cDNAs and genomic DNAs encoding the α1(XVIII) collagen chain. Utilizing a genomic clone as probe, we have mapped the COL18A1 gene to chromosome 21q22.3 by fluorescence in situ hybridization. In addition, using an interspecific backcross panel, we have shown that the murine Col18a1 locus is on chromosome 10, close to the loci for Col6a1 and Col6a2.
Political Benefits of Program Participation: The Case of Community Crime Prevention

This article explores the effects of citizen participation in policy through a case study of the implementation of a community crime-prevention program in Chicago. Although the program was successf...
Psychrotrophic Bacteria cause Changes in Stability of Milk to Coagulation by Rennet or Heat

Abstract Raw and pasteurized milks were inoculated with psychrotrophs, held at 7C for 8 days, and observed periodically for stability to coagulation by heat and rennet. The longer raw milks with or without added psychrotrophs were incubated, the more rapidly they were coagulated by rennet. Raw milks inoculated with Lactobacillus spp. (No. 29 and 34) and Pseudomonas spp. (No. 1,13,36) were coagulated more slowly by rennet than was uninoculated raw milk. All pasteurized and inoculated milks clotted in substantially less time than did pasteurized control milk when rennet was added. Clotting times of milks varied when different isolates of the same genus or of different genera served as inoculum. Coagulation of raw milks by rennet took less time for pasteurized inoculated milks. Uninoculated raw milk and raw milks inoculated with Pseudomonas spp. (No. 10,31), Flavobacterium sp., Micrococcus sp., and Lactobacillus sp. (No. 29) held for 6 and 8 days of refrigerated storage were coagulated by heat at 63, 73, and 85C for 30min. Pasteurized milk inoculated with Pseudomonas sp. (No. 31) was unstable to heat after 6 days at 7C. The pH of raw milks decreased slightly over the 8 days whereas the pH of inoculated milks which were pasteurized generally did not start to decrease until day 4 and then decreased only slightly.
Cavity Flow Predictions Based on the Euler Equations

An Euler solver based on artificial-compressibility and pseudo-time stepping is developed for the analysis of partial sheet cavitation in two-dimensional cascades and on isolated airfoils. The computational domain is adapted to the evolution of the cavity surface and the boundary conditions are implemented on the cavity interface. This approach enables the cavitation pressure condition to be incorporated directly without requiring the specification of the cavity length or the location of the inception point. Numerical solutions are presented for a number of two-dimensional cavity flow problems, including both leading edge cavitation and the more difficult mid-chord cavitation conditions. Validation is accomplished by comparing with experimental measurements and nonlinear panel solutions from potential flow theory. The demonstrated success of the Euler cavitation procedure implies that it can be incorporated in existing incompressible CFD codes to provide engineering predictions of cavitation. In addition, the flexibility of the Euler formulation may allow extension to more complex problems such as viscous flows, time-dependent flows and three-dimensional flows.
Small-scale spatial and temporal variability of N2O flux from a shrub-steppe ecosystem

Abstract Nitrous oxide (N 2 O) is a trace greenhouse gas that catalyses ozone destruction. It is also the major gaseous loss of N from the N-limited shrub-steppe ecosystem. We examined the spatial and temporal flux of N 2 O from small plots in an undisturbed shrub-steppe ecosystem having spatially heterogeneous plant cover. The N 2 O flux from the soil surface and NH 4 + N and NO 3 − N concentrations were measured periodically over 1 y from 44 points in 2.4 m 2 plots centered on individual Artemisia tridentata shrubs. Positive N 2 O flux occurred from March to October, with no detectable flux during the winter months. The spatial (plot) variability of N 2 O flux ranged from 23 to 130%, with lower variability as soil moisture increased. Temporal variability (March to October) was 171%, but decreased to 77% when calculated without the August sampling date. The measured N 2 O flux correlated positively with microbial activity (CO 2 production), with moisture when the soil was fairly wet and usually with NO 3 − N concentrations. After a precipitation event on to dry soil, there was a pulse of N mineralization and N 2 O flux, which strongly correlated with proximity to vegetation. The estimated N 2 O flux occurring within 48 h after warm season precipitation events accounted for 20% of the total annual N 2 O flux from this ecosystem. Thus, small-scale spatial and short-term temporal variations can significantly affect annual estimates of ecosystem N 2 O flux and, thus, gaseous N loss from semi-arid ecosystems.
Source pulse enhancement by deconvolution of an empirical Green's function

Observations of the earthquake source-time function are enhanced if path, recording-site, and instrument complexities can be removed from seismograms. Assuming that a small earthquake has a simple source, its seismogram can be treated as an empirical Green's function and deconvolved from the seismogram of a larger and/or more complex earthquake by spectral division. When the deconvolution is well posed, the quotient spectrum represents the apparent source-time function of the larger event. This study shows that with high-quality locally recorded earthquake data it is feasible to Fourier transform the quotient and obtain a useful result in the time domain. In practice, the deconvolution can be stabilized by one of several simple techniques. In this paper, the method is implemented and tested on high-quality digital recordings of aftershocks of the Jan. 9, 1982 Miramichi (New Brunswick) earthquake. In particular, seismograms from a Jan. 17 aftershock (017 13:33 GMT, local mag.=3.5) exhibit path or site effects which complicate the determination of source parameters. After deconvolution, the apparent far-field source of this event is a simple pulse in displacement with duration ≈ 0.07 second for both P and S.
Optimal Pump and Recharge Management Model for Nitrate Removal in the Warren Groundwater Basin, California

The town of Yucca Valley located in the southwest part of the Mojave Desert in southern California relies on groundwater pumping from the Warren groundwater basin as its sole source of water supply. This significant dependency has resulted in a large imbalance between groundwater pumpage and natural recharge, causing groundwater levels in the basin to decline more than 90 m from the late 1940s to 1994. Consequently, an artificial recharge program proposed by the Hi-Desert Water District, which provides water service to the town of Yucca Valley, was implemented for the purpose of recovering the groundwater levels; however, the rise in groundwater levels has caused nitrate ( NO3 ) concentration to increase simultaneously. The purpose of this study is to develop an optimal pump and recharge strategy for a planned conjunctive-use project to remove the high-nitrate concentration while maintaining groundwater levels at desired elevations at specified locations as well as meeting water demand. An optimization/ma...
Uptake and metabolism of 13C-chloramphenicol by Avena coleoptiles

Abstract The uptake and metabolism of 13 C-chloramphenicol by coleoptiles of Avena sativa (cv. Torch) were related to chloramphenicol inhibition of cell elongation and protein synthesis. While the rate of uptake may account for the lag period before the inhibition of cell elongation and protein synthesis, it is not the reason for the high concentration of chloramphenicol required to inhibit these processes. The antibiotic was not rapidly metabolized by the tissue.
Crossing the Border from Science Student to Science Teacher: Preservice Teachers’ Views and Experiences Learning to Teach Inquiry

Preservice science teachers face numerous challenges in understanding and teaching science as inquiry. Over the course of their teacher education program, they are expected to move from veteran science students with little experience learning their discipline through inquiry instruction to beginning science teachers adept at implementing inquiry in their own classrooms. In this study, we used Aikenhead’s (Sci Educ 81: 217–238, 1997, Science Educ 85:180–188, 2001) notion of border crossing to describe this transition preservice teachers must make from science student to science teacher. We examined what one cohort of eight preservice secondary science teachers said, did, and wrote as they both conducted a two-part inquiry investigation and designed an inquiry lesson plan. We conducted two types of qualitative analyses. One, we drew from Costa (Sci Educ 79: 313–333, 1995) to group our preservice teacher participants into one of four types of potential science teachers. Two, we identified successes and struggles in preservice teachers’ attempts to negotiate the cultural border between veteran student and beginning teacher. In our implications, we argue that preservice teachers could benefit from explicit opportunities to navigate the border between learning and teaching science; such opportunities could deepen their conceptions of inquiry beyond those exclusively fashioned as either student or teacher.
The release into the environment of genetically engineered viruses, vaccines and viral pesticides

Viruses are being developed by genetic engineering procedures for two purposes: as improved vaccines or vectors for inserting foreign genes into a vaccinated hosts, and as improved viral pesticides. Both uses raise environmental issues.
Exercise training improves hemodynamic recovery to isometric exercise in obese men with type 2 diabetes but not in obese women.

Objectives Women with type 2 diabetes (T2D) show greater rates of mortality due to ischemic heart disease than men with T2D. We aimed to examine cardiovascular and autonomic function responses to isometric handgrip (IHG) exercise between men and women with T2D, before and after an exercise training program.
Invalid use of the Beck Depression Inventory to identify depressed college-student subjects: A methodological comment

Failure to reassess depression level immediately prior to conducting depression experiments using college-student subjects threatens the validity of the interpretation of results. This rather serious methodological error may hamper progress in depression research if unattended to by researchers (and reviewers) in the area. A recent article by Craighead, Hickey, and DeMonbreun (1979) is used to illustrate this methodological problem, though a survey of other published papers in the area indicates that the Craighead et al. (1979) study is clearly not an isolated example. The article (Craighead et al., 1979) describes an experiment that attempted to test a hypothesis derived from Beck's (1967) cognitive theory of depression, namely, that depressed subjects will distort their perception and recall of neutral task-performance feedback in a negative direction. The authors failed to find support for the hypothesis and proceeded to discuss the results as an apparent inconsistency with Beck's theory and the previous findings of others. However, the procedure used by these researchers for selection of depressed subjects is erroneous and therefore precludes any valid conclusions regarding the theoretical or empirical implications of their results.
[NZP], a new radiophase for ceramic nuclear waste forms

Abstract The NZP structure is a candidate for immobilization of certain types of nuclear waste. It will incorporate 137Cs, 90Sr, and a range of other nuclides. The leach resistance of CsZr2(PO4)3 appears to be comparable with that of other phases under consideration for radio-Cs immobilization. This phase can be formed by sintering at ∼850°C; it is reasonably refractory, and it is compatible with monazite, a favored immobilizing agent for waste actinides.
Gossypol inhibits proliferation of endometrioma cells in culture

Aim: To evaluate the anti-proliferative activity and mitochondrial toxicity of gossypol in endometrioma cells maintained in short-term cultures. Methods: (A) Three endometrioma cell lines from patients were treated with 25 or 50 nmol/L gossypol for up to 12 days. The effect of gossypol on the cell growth was recorded. (B) A phosphorescence oxygen analyzer was used to determine the effects of gossypol on mitochondrial oxygen consumption of six endometrioma cell lines from patients. (C) Cellular gossypol accumulations in three endometrioma cell lines from patients were measured by high-pressure liquid chromatography. Results: Proliferation of the endometrioma cells was inhibited by 25 and 50 nmol/L gossypol. Respiration of the endometrioma cells was inhibited by 10 μmol/L gossypol. Cellular gossypol was detected in the endometrioma cell lines that were treated for 24 h with 10 and 0.3 μmol/L gossypol. Conclusion: Gossypol invokes a potent toxicity on cultured endometrioma cells.
Two-Sample Tests for Compound Distributions for Homogeneity of Mixing Proportions

This paper is concerned with a problem of comparing two compound distributions each with components f 1(x) and f 2(x), and with mixing proportions px and (1 – px ) for the first, and py and (I – py ) for the second distribution, respectively. Four methods are proposed for testing the hypothesis Ho :px = py . The first two tests are based on the asymptotic normality of two unbiased estimators for py – px , and the other two are nonparametric tests. The asymptotic power functions for the tests are given and a simulation technique is used to compare the efficiencies of the four tests applied for mixed normal and for mixed exponential distributions.
Evidence for Only One β-Luteinizing Hormone and No β-Chorionic Gonadotropin Gene in the Rat*

We have examined the rat genome and placenta for the presence of a mRNA or gene which codes for a protein identical or similar to the β-subunit of LH. A cDNA clone was isolated that encodes for amino acids 44 through 121 of the mature β-subunit of rat LH (rLH). This rβLH cDNA was used as a hybridization probe to study the structure of the gene(s) which encode for the β-subunit of either LH or a LH-like protein in the rat genome. Restriction enzyme digestion analysis of rat genomic DNA using Southern blots revealed only one fragment that hybridized to 32P-labeled rβLH cDNA. In contrast, restriction enzyme analysis of human and rhesus monkey genomic DNA (known to have both LH and CG) gave multiple fragments which hybridized to a 32P-labeled human βLH DNA. We have also examined the possibility of a mRNA which can encode the β-subunit of either LH or CG in the rat placenta. Northern blot analysis of total RNA isolated from rat placenta and rat anterior pituitary revealed that only the anterior pituitary conta...
Acyl coenzyme a: 2-acyl-sn-glycerol-3-phosphate acyltransferase activity in rat liver microsomes

SUMMARY z-Acylglycerol-3-phosphate can be acylated by acyl-CoA in the presence of microsomal preparations from rat liver. With optimal amounts of substrate, the acyltransferase reaction to the r-position occurred at about one tenth the rate observed for the z-position. Oleate was esterified more rapidly than palmitate or stearate under the conditions used. The enzymic activity catalyzing esterification of the primary hydroxyl seems to be different from that for the secondary hydroxyl.
Control performance simulation in the design of a flapping wing micro-aerial vehicle

Flapping wing micro-aerial vehicles (MAVs) hold great potential for matching the agility of flies, their source of inspiration. At small scales, however, it becomes difficult to balance design mechanical complexity and the weight/lift ratio. Considering control in the initial stages of vehicle design can help define system feasibility and the consequences of making design simplifications. Here, four design alternatives based on a piezoelectric driven passive pitch reversal wing are modeled and compared based on their performance under an ideal linear quadratic regulator (LQR) control scheme. State error over straight line, circular, and cube trajectories are used as a means of comparison. Wing lift and reasonable control input bounds are defined for each design variation. While not nearly as maneuverable as flies, these designs show promise as feasible controllable vehicles.
The denervated gastric pouch of the rat

Abstract A method of constructing a denervated gastric pouch in the rat is described. Advantages of this preparation over others in the rat are discussed. The secretory response of the unstimulated pouch is reported as well as the response to histamine, food, and reserpine.
9(Z)-Octadecenamide and fatty amides byBacillus megaterium (B-3437) conversion of oleic acid

9(Z)-Octadecenamide, hexadecenamide, tetradecenamide and tetradecanamide were produced by a novel bioconversion of oleic acid withBacillus megaterium NRRL B-3437. Although chemical synthesis is more practical, the bioconversion to fatty amides (5–7% of total recovered lipids) was unique for its requirement of both enzymatic catalysis and equimolar oleic acid/ammonium salt substrates. Purified octadecenamide was obtained by silica gel and high-pressure liquid chromatographic procedures and was characterized by gas chromatography, mass spectrometry, infrared and nuclear magnetic resonance.
Building a case against economic development

Although development is widely held to be the solution to poverty in the Third World, a case can be made that it is a part of the problem. It is commonly believed that development eradicates poverty through increased production of goods and services, but the past history of that activity also contains an unacknowledged history of socially-constructed scarcity. Poverty is a form of development-induced scarcity caused by the playing out of production relations located within a nexus of interacting technical, social, political, cultural, ecological, and academic relations. In that sense poverty is caused by multiple forces acting within a discursive materialist formation. We have used an analytical framework called “the nexus of production relations” to elucidate these ideas. This framework also suggests that the opportunities available to the poor for meeting their needs are far more varied and numerous than theories of economic development would have us believe.
Future directions in the management of non-small cell lung cancer

Abstract In the past decade we have witnessed major advances in both the treatment and biologic understanding of lung cancer. There is evidene for the first time that chemotherapy with cisplatin-based regimens has a small, but definite, effect on overall survival in Stages II–IV non-small cell lung cancer (NSCLC). The discovery of activation and mutations of oncogenes such as ras has led to new prognostic markers. The discovery of the loss of suppressor genes such as P53 on chromosome 17 and other genes on chromosome 3p has led to new theories of pathologenes and new potential intervention strategies. The discovery of changes in cell surface antigen express has led to new tools for early detection, staging, and a potential means to target therapy using monoclonal antibodies. The discovery of peptide and other growth factors is leading to new treatment and prevention strategies. Chemoprevention agents such as 13- cis -retinoic acid are being evaluated for their potential to prevent lung cancer in high-risk patients. In surgical resectable patients, cisplatin-based regimens are being evaluated in the neoadjuvant and adjuvant settings. In locally inoperable patients, new ways of combining cisplatin-based regimens and radiotherapy are prolonging survival; further evaluation is under way. The role of postchemotherapy surgery also is being evaluated in Phase III studies for these patients. In metastatic disease, cisplatin-based regimens appear to have made a small impact on survival and new active agents have been discovered. These will be combined with cisplatin-based regimens and future trials. Combined etoposide and cisplatin has produced results equivalent or superior to any other regimen with considerably less toxicity. This two-drug regimen can be considered standard therapy for patients with limited and extensive small cell lung cancer and with inoperable NSCLC. We can proceed through the 1990s with the hope that the advances of the 1980s will yield a significant reduction in lung cancer mortality rates.
Relay Wireless Network Communication Protocol Technology Based on Balanced Energy and Distance

Optimizing the energy consumption of sensor node and prolonging the network lifetime are the key steps to enable the wireless sensor network to enter into practical applications. This paper focuses on studying the energy efficient wireless sensor network routing protocol from the perspective of node energy consumption efficiency and balance, designing the Energy Balanced Adaptive Clustering Hierarchical Protocol (EBACH) and two-layer transceiver model, improving data transmission process to conform to the energy-saving principle of wireless multi-hop data transmission, and analyzing the feasibility and accuracy of the algorithm through simulation.
Extrapolation of physiological parameters for physiologically based simulation models

Masses of organs and fluids, pulmonary ventilation and cardiac output and its distribution are the basic input data used in physiologically based pharmacokinetic models. Since these parameters are rarely measured in pharmacokinetic studies, the values found in reference books or extrapolated to meet the specific exposure conditions are used in the models. In this review of the extrapolation of pertinent physiological parameters, power equations for scaling across mammals, adjustments to body build (lean body mass) and physical activity of humans and their significance for risk assessment of human exposure to solvents using animal data are assessed.
Searching strategies and attack rates of parasitoids of the ash bark beetle (Leperisinus varius) and its relevance to biological control.

. 1 Point estimates of parasitoid behaviour indicated that braconid parasitoids of the bark beetle, Leperisinus varius, spend 70% of their host searching time stationary on the bark surface, in sharp contrast to the chalcidoid parasitoids which spend 60–70% of their host searching time moving across the bark surface. 2 Aggressive encounters between searching parasitoids are common and the data suggest that they do not occur at random. 3 The chalcidoid parasitoids, Cheiropachus quadrum and Eurytoma morio, are more frequently involved in aggressive encounters than expected and can displace ovipositing individuals of other species. 4 Attack rates for the parasitoids were estimated to vary from two hosts per day for the braconid Coeloides filiformis to four hosts per day for E.morio, and net reproductive rates vaned from 6.3 for C.filiformis to 0.8 for Coeloides melanotus. 5 These data suggest that while all parasitoids of the scolytid can act as primary parasitoids, at least some of the chalcidoid parasitoids are facultative cleptoparasitoids and should be avoided in classical biological control introductions.
Crowding-induced organization of cytoskeletal elements. III. Spontaneous bundling and sorting of self-assembled filaments with different flexibilities

The typical cell contains ca. 25 vol.-% protein, of which ca. 10% forms cytoskeletal filaments and ca. 90% is non-aggregating globular protein. It has previously been theoretically predicted that, under such highly crowded conditions, rigid filaments will coalesce into tight bundles coexisting with an isotropic solution of globular proteins. In the present work we show that such spontaneous bundling will occur even when filament flexibility is taken into account because the persistence length of the filaments is much longer than the diameter of the globular proteins. The theoretical results are consistent with experimentally observed bundling of F-actin (the most flexible of the three most common types of cytoskeletal filaments) in the presence of globular macromolecules.The main effect of increased filament flexibility on bundling is to cause somewhat looser packing. In mixtures of filaments, differences in flexibilities can lead to segregation. This segregation is accentuated when the stiffer filament is also wider. The results suggest that actin filaments and microtubules will spontaneously form segregated bundles in the presence of cellular concentrations of globular proteins. While cross-linking proteins may serve to stabilize these bundles, their more important function in bundling may be to fine tune the structure (e.g., polarity and registration of filaments).
Suppression of innate immunity by a nasal carriage strain of Staphylococcus aureus increases its colonization on nasal epithelium

Nasal carriage of Staphylococcus aureus is an important source of nosocomial infection and community-acquired methicillin-resistant S. aureus (MRSA). Previous studies by our laboratory revealed that nasal carriage of S. aureus is accompanied by subclinical inflammation, which is insufficient to prevent colonization, and that carriage might also be a result of adaptation and selection of certain S. aureus strains to the host's nasal environment. In the present study we observed that a carrier strain of S. aureus preferentially colonizes and attaches to nasal epithelial cells (NEC) compared to a non-carrier S. aureus strain. Conversely, when naive NEC were pretreated with interleukin-1beta for 24 hr, the growth and attachment of the carrier strain of S. aureus were significantly reduced in comparison to the non-carrier strain, emphasizing the pivotal role played by host innate immunity in the initial events of nasal carriage. While both strains up-regulated the expression of the pattern recognition receptor, Toll-like receptor 2 (TLR2), NEC exposed to the nasal carrier strain had a 4-hr delay in TLR2 expression compared with NEC exposed to non-carrier S. aureus. Moreover, even after 20 hr of colonization the expression of two principal epithelial antimicrobial peptides, human beta-defensin-2 and human beta-defensin-3, was negligibly induced in NEC exposed to the nasal carrier strain of S. aureus in comparison to the non-carrier strain. These results suggest that carrier strains of S. aureus retain a competitive advantage over non-carrier strains by delaying the host's innate response to epithelial colonization and infection.
A new method of growth analysis for plants that experience periodic losses of leaf mass

Summary 1. A new method (the iterative approach) is presented by which growth analyses can be conducted on plants that have been subjected to significant losses in biomass and leaf area between harvests. The method is particularly useful to analyse the effects of defoliation on growth and biomass allocation. 2. Values for the following parameters can be estimated: absolute growth rate (g day ‐1 ), relative growth rate (RGR, g g ‐1 day ‐1 ), net assimilation rate (NAR, g m ‐2 day ‐1 ), leaf area ratio (LAR, m 2 g ‐1 ), fraction of newly assimilated mass that is allocated to leaf lamina production ( flam, g g ‐1 ), and daily fractional change in the average specific leaf area of plants (ρ, day ‐1 ). These parameters are determined by means of iterations. We defined a number of growth functions, and the values of NAR, flam and the SLA of newly produced leaves were changed until these functions correctly predicted the measured total plant mass, leaf lamina mass and leaf area at the end of the growth period. This avoids having to assume a constant relationship between leaf area and biomass (as in the ‘classical’ approach), and it avoids the use of polynomial functions to fit growth data (as in the ‘functional’ approach) that are unsuitable for fitting data sets exhibiting discontinuities such as abrupt changes in biomass. 3. The method was applied to a greenhouse experiment in which we analysed the effects of sustained defoliation on growth and biomass allocation in a tropical understorey palm, Chamaedorea elegans Mart. 4. We showed that C. elegans plants respond to defoliation with a considerable increase in the allocation of new assimilates to lamina growth ( flam) and that, despite the repeated loss of leaf area and associated reductions in LAR, they had RGR values that were similar to those of undamaged plants.
The Effect of Authentic Oral Texts on Student Listening Comprehension in the Foreign Language Classroom.

ABSTRACT The current study determined the effect of authentic, unedited radio features on student listening skills in the foreign language classroom. Twenty-three students in two classes of intermediate French participated in the research. The basic instructional approach and materials for the two classes of students were identical. The groups differed only in that classwork, in the experimental condition, was regularly supplemented with Champs-Elysees, an unedited radio program produced in Paris. Student listening comprehension skills at the end of the fifteen-week semester were superior in the experimental condition as measured on two different aural tests of unedited native speech. Results confirmed that listening comprehension improves with increased exposure to authentic speech. The current study suggests that adjusting levels of speech (speed, content, and form) to students' developing comprehension, while perhaps helpful to the intermediate-level foreign language student, might not be essential to improvement of listening skills.
Intravenous Catheter Embolization to the Pulmonary Artery

A case of intravenous catheter embolization to the pulmonary artery is described and the literature reviewed. Prolonged use of indwelling catheters provides a portal for long term infusion of fluids, recording pressures, and withdrawal of blood for measurement of chemistries. Complications can be avoided if strict criteria are followed and aseptic technique maintained.
Effects of 2'-deoxycoformycin on HL-60 cell differentiation, adenosine deaminase, and oligoadenylate synthetase.

There is evidence that 2′-deoxycoformycin (DCF) functions as a differentiating agent. We examined the effects of DCF on the differentiation of HL-60 cells, a standard model of leukemic cell differentiation. DCF did not induce morphologic or histochemical evidence of differentiation, nor did it interact with retinoic acid, 1,25-dihydroxyvitamin D3, or interferon-gamma in inducing differentiation. Furthermore, DCF and agents that differentiated HL-60 cells had opposing effects on adenosine deaminase and 2′, 5′-oligoadenylate synthetase activity.
Linear scale-invariant system models for self-similar wireless traffic characterization

It is now empirically documented that data traffic over networks of various types exhibit fractal or self-similar behavior in many instances. Accurate analysis of traffic density and estimation of buffer size must take into account this self-similar nature. Researchers have investigated procedures for generating self-similar signals to model the traffic. Approaches based on the discrete wavelet transform (DWT) are among those that have been proposed. The basis for using the DWT is that it possesses certain scale-invariance properties and scale-invariance provides the foundation for characterizing self-similarity. However, self-similar processes generated with the DWT demonstrates self- invariance to dyadic scaling factors. Zhao and Rao have proposed novel models for purely discrete-time self-similar processes and linear scale-invariant (LSI) systems based on a new interpretation of the discrete-time scaling (equivalently dilation or contraction) operation which is defined through a mapping between discrete and continuous time. They show that it is possible to have continuous scaling factors through this operation although the signal itself is discrete-time. In this paper, we demonstrate application of these LSI systems to the synthesis of data whose self-similarity parameters match those observed in network traffic. Both theoretical development and experimental results are provided.
D-Tryptophan-6 analog of luteinizing hormone-releasing hormone as a protective agent against testicular damage caused by cyclophosphamide in baboons.

Abstract Possible protective effects of the agonist [D-Trp6]LH-RH (the D-tryptophan-6 analog of luteinizing hormone-releasing hormone) against testicular damage caused by cyclophosphamide (Cytoxan) were investigated in subhuman primates. Three adult male baboons (Papio anubis) were first subjected to normal semen evaluation by using electroejaculation. The average baseline count for the animals ranged from 95.7 X 10(6) to 585.7 X 10(6) sperm per ml with 90% normal forms and 85% motility with excellent rapid forward progression. After baseline evaluations, two of the animals were treated with daily subcutaneous injections of 0.5 mg of the agonist [D-Trp6]LH-RH. There was an initial rise in serum testosterone after 1 week, but testosterone fell to castration values at 1 month and continued at these levels during treatment with the agonist. There was also an initial rise in sperm concentration 1 month after treatment was started, but after 2 months the animals were azoospermic. After 13 weeks of therapy with [D-Trp6]LH-RH, these two baboons and a third untreated control animal were given cyclophosphamide at a dose of about 3 mg/kg of body weight per day for 4 months. The two animals pretreated with [D-Trp6]LH-RH, continued to receive this agonist until 1 week after the last dose of Cytoxan. In one of the two baboons treated with Cytoxan and the LH-RH agonist, the white blood count fell below 4000 per microliter, and the dose of Cytoxan had to be reduced to 1.5 mg/kg per day for 12 days. The control animal developed azoospermia after 4 months of treatment with cyclophosphamide, and serum testosterone increased while sperm count decreased. Four weeks after the agonist was stopped, serum testosterone in both animals pretreated with [D-Trp6]LH-RH returned to normal levels. The control animal showed a small amount of nonmotile sperm 2.5 months after cessation of treatment, but after 9 months remains oligospermic with poor sperm motility. In one of the animals treated with LH-RH agonist, semen analysis returned to normal pretreatment values 8 months after withdrawal of treatment. The other animal remains oligospermic 10 months after therapy, but the motility is improving. These preliminary results suggest that treatment with LH-RH agonist might decrease the gonadal damage caused by some chemotherapeutic agents.
Biochemical networks: The evolution of gene annotation

Complete and accurate annotation of gene function is an essential starting point for genome interpretation and a host of systems and synthetic biology endeavors. Detecting errors in existing annotation now has an important new tool.
Numerical analysis of elliptic reflector radiating into lossy dielectric half-space

Numerical analysis of an elliptic reflector above a lossy dielectric half-space is presented. The equivalence principle is used in the combined-field surface integral equations for the currents on the reflector and air-to-lossy-half-space interface. An approximate model for the equivalent electric and magnetic currents on the interface is used to calculate the fields inside the lossy half-space. The numerical results show that the lossy half-space is an effective tool for focusing the radiated beam; especially in the shallow region, even for high values of the lossy permittivity. >