cssi/SciSciGPT-SciSciNet huggingface dataset:
Multi-focusing and sustained dissipation in the dissipative nonlinear Schrödinger equation

Abstract The possibility of physically relevant singular solutions of the nonlinear Schrodinger equation with sustained dissipation into the singularity is considered through numerical study of a nonlinear dissipative regularisation and its small dissipation limit. A new form of such dissipative solutions is conjectured for certain parameter ranges where this behaviour was previously not expected, including the two-dimensional case of laser self-focusing, involving a multi-focusing mechanism. The space and time structure of such solutions for very small values of the nonlinear dissipation parameter is studied numerically and compared to a conjectured mechanism related to a new family of stationary singular solutions of the NLSE.
Modelling communication network challenges for Future Internet resilience, survivability, and disruption tolerance: a simulation-based approach

Communication networks play a vital role in our daily lives and they have become a critical infrastructure. However, networks in general, and the Internet in particular face a number of challenges to normal operation, including attacks and large-scale disasters, as well as due to mobility and the characteristics of wireless communication channels. Understanding network challenges and their impact can help us to optimise existing networks and improve the design of future networks; therefore it is imperative to have a framework and methodology to study them. In this paper, we present a framework to evaluate network dependability and performability in the face of challenges. We use a simulation-based approach to analyse the effects of perturbations to normal operation of networks. We analyse Sprint logical and physical topologies, synthetically generated topologies, and present a wireless example to demonstrate a wide spectrum of challenges. This framework can simulate challenges on logical or physical topologies with realistic node coordinates using the ns-3 discrete event simulator. The framework models failures, which can be static or dynamic that can temporally and spatially evolve. We show that the impact of network challenges depends on the duration, the number of network elements in a challenge area, and the importance of the nodes in a challenge area. We also show the differences between modelling the logical router-level and physical topologies. Finally, we discuss mitigation strategies to alleviate the impact of challenges.
Simple size-selective separation and microscopic characterization of Phe–Phe nanotubes and study of its internalization inside CHO cells

Phe–Phe nanotube internalization in Chinese hamster ovary (CHO) cells is imaged through the transmission electron microscopic (TEM) study. Size-selective separation of peptide nanotubes (NTs) is of great value when we think about its application in biocompatible drug delivery. This paper describes a simple size-selective separation protocol for separating Phe–Phe NTs. During the synthesis, it is commonly observed that peptide NTs are formed with a range of sizes in their width and length and hence easy separation techniques of NTs are essential. Removal of the monomers from NTs is also important. Microscopic imaging of peptide NTs is also important in this context and particularly when these are used in the diagnostic and therapeutic purposes. Herein, we report a straightforward size-selective separation of peptide NTs by size exclusion chromatography (SEC) and imaging the fractions through TEM, confocal, and deconvolution microscopic techniques. Here, we report, for the first time, use of deconvolution fluorescence microscopy to detect NTs. As commonly used photo microscope cannot resolve the images of very small particles (e.g., less than micron scale), electron microscopy is widely used in imaging of NPs. Hence, systematic peptide NTs separation followed by these characterization techniques provides an option to study the internalization of NTs inside cells. Intake of peptide NTs inside cells is promising for their use in drug delivery as well as in imaging study.
Facilitating participatory decision-making in local communities through map-based online discussion

GIS has been widely used for supporting decision-making in local communities. However, limited studies have been conducted to use maps directly as a communication tool to support community discussion. In this paper, we explore the potential of using geospatial annotations to facilitate map-based online discussion in local communities. We developed a prototype system, which explicitly links participants' discussion contributions with geographic references. The system is based on conceptual understanding of map-based discussion space, which guides the generation of system requirements. We demonstrate the utility of such systems by a hypothetical scenario of building a Smoke-Free campus in a university community.
Lymph node-positive stage IIIC ovarian cancer: a separate entity?

Introduction: Ovarian cancer spreads via the retroperitoneal lymphatics, and these lymph nodes frequently contain metastasis. A subset of patients whose disease was classified as stage IIIC has retroperitoneal lymph node metastases in the pelvic and/or para-aortic lymph nodes without intraperitoneal carcinomatosis and was upstaged from stage I to IIIB diseases based on these findings. Patients undergoing cytoreductive surgery for advanced-stage ovarian cancer undergo concomitant retroperitoneal lymphadenectomy in an effort to improve their survival. Methods: Stratification of patients with stage IIIC ovarian cancer by lymph node status and presence and extent of metastatic disease in the peritoneal cavity has been performed. Studies have determined the impact on disease-free and overall survivals of the resection of retroperitoneal lymph nodes as part of primary and secondary cytoreductive operations. Results: The overall survival of patients with stage IIIC ovarian cancer based on retroperitoneal lymph node metastasis without peritoneal carcinomatosis is 58% to 84% compared with 18% to 36% for those with macroscopic peritoneal carcinomatosis. Although the performance of a pelvic and para-aortic lymphadenectomy in patients with stage IIIC to IV diseases has been reported to prolong survival, an international randomized study did not confirm this finding. Patients who undergo secondary resection of isolated recurrent lymph node metastasis have a better survival than those with more extensive recurrent disease. Conclusions: These data support the stratification of patients with stage IIIC ovarian cancer based on the finding of metastasis to the retroperitoneal lymph nodes without peritoneal carcinomatosis versus those who have peritoneal carcinomatosis. The International Federation of Gynecology and Obstetrics Committee should consider modifying the ovarian cancer staging system by further stratifying stage III disease. Although systematic lymphadenectomy during primary cytoreductive surgery does not appear to improve overall survival, resection of isolated lymph node metastasis and recurrences in lymph nodes may be associated with a survival benefit.
Determining the location and capacity of competitive facilities

This paper examines a competitive facility location problem in which the objective is to increase market capture subject to an expansion budget. This is accomplished by determining both the locations for a set of new facilities and the capacities of new and existing facilities. A gravity-based elastic-demand utility model is presented, in which the capacity of a facility serves as its measure of attractiveness. An examination of problem characteristics suggests that the model be divided into two subproblems. The first subproblem identifies locations for new facilities, and is solved using a penalty function formulation with fixed-point iteration. The second subproblem determines facility capacities and it is solved using a Successive Linear Programming algorithm. The interfacing of the two subproblem procedures into an iterative algorithm for solution of the overall problem is discussed. Computational testing shows the iterative algorithm to be superior to a general-purpose non-linear solver.
Effect of chlorpromazine and quinacrine on the lethality in mice of the venoms and neurotoxins from several snakes.

Abstract R. D. Crosland . Effect of chlorpromazine and quinacrine on the lethality in mice of the venoms and neurotoxins from several snakes. Toxicon 27, 655–663, 1989.—Antivenoms are the currently available agents for the treatment of intoxication by snake venoms. Therapeutic approaches using more generally available drugs could improve treatment of envenomation by reducing the cost of the therapeutic agent, eliminating hypersensitivity reactions to antivenoms, and reducing storage costs. I investigated the efficacies of chlorpromazine and quinacrine with respect to reducing the lethality in mice of Bungarus caeruleus venom, Bungarus multicinctus venom and its neurotoxic components α- and β-bungarotoxin, Crotalus durissus terrificus venom and its neurotoxic component crotoxin, and Oxyuranus scutellatus venom and its neurotoxic component taipoxin. Venom or toxin was administered i.p., followed immediately by an i.p. injection of chlorpromazine or quinacrine. The effect of drug on the lethality of the venom was recorded 24 hr later. Chlorpromazine and quinacrine were effective antagonists of the lethality of B. caeruleus venom, B. multicinctus venom, and β-bungarotoxin without themselves being overtly toxic. Chlorpromazine (1 mg/kg) increased the ld 50 of B. caeruleus venom, B. multicinctus venom, and β-bungarotoxin by 8.6-, 2.6- and 3.7-fold, respectively. In the range of 1 to 5 mg/kg, quinacrine increased the ld 50 of B. caeruleus venom, B. multicinctus venom and β-bungarotoxin by 5.7-, 11- and 8.6-fold, respectively. Neither drug had any effect on the other venoms or toxins. Chlorpromazine and quinacrine were also injected at different times both before and after the injection of venom or toxin. Protection from lethality was maximal for both drugs when they were administered immediately after injection of venom or toxin.
Comparison of aerobic and photosynthetic Rhodobacter sphaeroides 2.4.1 proteomes

The analysis of proteomes from aerobic and photosynthetic Rhodobacter sphaeroides 2.4.1 cell cultures by liquid chromatography-mass spectrometry yielded approximately 6,500 high confidence peptides representing 1,675 gene products (39% of the predicted proteins). The identified proteins corresponded primarily to open reading frames (ORFs) contained within the two chromosomal elements of this bacterium, but a significant number were also observed from ORFs associated with 5 naturally occurring plasmids. Using the accurate mass and time (AMT) tag approach, comparative studies showed that a number of proteins were uniquely detected within the photosynthetic cell culture. The estimated abundances of proteins observed in both aerobic respiratory and photosynthetic grown cultures were compared to provide insights into bioenergetic models for both modes of growth. Additional emphasis was placed on gene products annotated as hypothetical to gain information as to their potential roles within these two growth conditions. Where possible, transcriptome and proteome data for R. sphaeroides obtained under the same culture conditions were also compared.
Versioned Hypermedia can improve software document management

This research was supported by the U. S. Department of Defense and by NSF CAREER award CCR-9734102. The Software Concordance project is addressing the software document management problem by providing a fine-grained version control model for software documents and their relationships using hypermedia versioning. A set of tools needed to maintain, visualize and analyze software documents is being constructed. This short paper presents research issues, initial results and a scheme for using hypermedia versioning and time stamps to automate detection of possible semantic non-conformance among software artifacts.
Investigation of volcanic gas analyses and magma outgassing from Erta' Ale lava lake, Afar, Ethiopia

Abstract The analyses of 18 volcanic gas samples collected over a two-hour period at 1075°C from Erta' Ale lava lake in December 1971 and of 18 samples taken over a half-hour period at 1125–1135°C in 1974 display moderately to intensely variable compositions. These variations result from imposed modifications caused by (1) atmospheric contamination and oxidation, (2) condensation and re-evaporation of water during collection, (3) analytical errors, and (4) chemical reactions between the erupted gases and a steel lead-in tube. Detailed examinations of the analyses indicate the erupted gases were at chemical equilibrium before collection. This condition was partially destroyed by the imposed modifications. High-temperature reaction equilibria were more completely preserved in the 1974 samples. Numerical procedures based on thermodynamic calculations have been used to restore each analysis to a composition representative of the erupted gases. These procedures have also been used to restore the anhydrous mean compositions reported for two series of collections taken at the lava lake in January 1973. The corrected analyses for 1971 and 1973 have similar compositions (69.6–71.3% H 2 O, 1.6–2.4% H 2 , 17.8–19.4% CO 2 , 0.8–1.6% CO, 4.9–8.8% SO 2 , 0.2–0.5% S 2 , and 0.4–1.0% H 2 S); those for 1974 were somewhat different (77.1% H 2 O, 1.6% H 2 , 11.7% CO 2 , 0.5% CO, 7.4% SO 2 , 0.3% S 2 , 0.9% H 2 S and 0.4% HCl). The O 2 and S 2 fugacities of all restored analyses are similar when compared at the same temperatures. O 2 fugacities are close to those of the quartz-magnetite-fayalite buffer. The restored analyses show no evidence of significant short-term (minutes, hours) variations in the compositions of the gases released from the lava lake, and evidence of long-term variations is limited. The restored analyses indicate the O 2 and S 2 potentials of the lava lake remained nearly constant from 1971 to 1974. However, there is a relative decrease in CO 2 between the 1973 and 1974 corrected compositions. This change is qualitatively compatible with magma outgassing controlled by solubility differences and could reflect a longer term trend. The chemistry of the Erta' Ale gases is consistent with models invoking the generation of basalts resembling mid-ocean ridge tholeiites along axial zones of crustal spreading in the Afar Triangle. The CO 2 -rich vesicle gases of submarine basalts and the relatively H 2 O-rich volcanic gases of Erta'Ale appear to be end-member compositions of an outgassing trend controlled largely by the effect of pressure on volatile solubilities in tholeiitic basalts from spreading zones. By analogy with submarine basalts H 2 O and sulfur in the Erta' Ale gases are mainly contributed by magma outgassing down to shallow depths (50–250 m); CO 2 contributions probably come from larger volumes of magma down to depths of at least 1000 m.
Growth processes in a cascade of bioreactors: Comparison of modeling approaches

The theory of a two-tank cascade of bioreactors developed by Mantzaris et al. (1998) was used to calculate the performance of such a cascade predicted by two chemically structured models: one for gene expression of Bentley and Kompala (1989) and Bentley et al. (1991) and the other a cybernetic model of Kompala et al. (1986) for multiple substitutable substrates. Two modeling approaches developed previously--one that accounts for biomass segregation and one that does not--were used with the model of Bentley and Kompala (1989) and Bentley et al. (1991). These modeling approaches showed that, in general, biomass segregation is an important feature of what happens in the second tank of the cascade and cannot be neglected. The same two approaches as well as a third approach based on the use of a chemically unstructured model were applied to the model of Kompala et al. (1986). It was found that biomass segregation in the second tank was important under some circumstances but not all and that the unstructured model failed to describe accurately what happens in the second tank under all circumstances.
Kinetics and Mechanism of Cyclohexanol Dehydration in High-Temperature Water

We examined cyclohexanol dehydration in pure water at temperatures of 250, 275, 300, 350, and 380 °C with water densities ranging from 0.08 to 0.81 g/cm3. Under these conditions, cyclohexanol dehydrates readily in the absence of added catalysts to form cyclohexene as the major product. The most abundant minor products are 1- and 3-methyl cyclopentenes. The reaction rate and product distribution at 380 °C show a remarkable sensitivity to the water density. At low densities, the reaction is slow, and cyclohexene is the only product. At high densities, the reaction is nearly complete, and methyl cyclopentenes appear along with cyclohexene. The experimental results implied a reaction mechanism that comprises two pathways: (1) reversible cyclohexanol dehydration to form cyclohexene through an E2 mechanism, and (2) subsequent cyclohexene protonation to form the cyclohexyl cation, which rapidly rearranges to form methyl cyclopentyl cations, which then lose a proton to form methyl cyclopentenes. A kinetics model...
Antibodies to testicular antigens in vasectomized rabbits.

Abstract Circulating antibodies to testicular antigens have been found in 27 of 46 bilaterally vasectomized rabbits. Approximately 30% of these rabbits had antibodies detectable by tanned cell hemagglutination, 50% by complement fixation. 33% by indirect immunofluorescence (IF) on cryostat sections of testis, 50% by indirect IF on sperm smears, and 11% by precipitation in agar. Indirect IF on sections of testis showed staining in the central and intermediate parts of the seminiferous tubules but no reactions in the basal layers of the tubules or in the interstitial tissue. Indirect IF on sperm smears showed staining of the acrosomal region of spermatozoa. None of the prevasectomy sera from the same rabbits and none of the sera from 13 sham-vasectomized and 20 normal untreated rabbits gave positive reactions. The percentage of positive animals increased with time after vasectomy. Antibodies to testicular antigens were usually detected 6 months following vasectomy, when the incidence was 8% by indirect IF on sperm smears. The percentage increased in the following months, reaching a maximum of 37% at 18 months. Bilaterally vasectomized rabbits with high titers of antibodies to testicular antigens may be a good model for the study of the possible immunological effects of vasectomy.
Economics of Annual Cropping versus Crop–Fallow in The Northern Great Plains as Influenced by Tillage and Nitrogen

Annualized yields with more intensive cropping (IC) systems tend to be greater than those of spring wheat-fallow (SW-F); however, little economic comparison information is available. The long-term (12 yr) effects of tillage system and N fertilization on the economic returns from two dryland cropping systems in North Dakota were evaluated. An IC rotation [spring wheat (Triticum aestivum L.)-winter wheat (T. aestivum L.)-sunflower (Helianthus annuus L.)] and a SW-F rotation were studied. Tillage systems included conventional till (CT), minimum till (MT), and no-till (NT). Nitrogen rates were 34, 67, and 101 kg N ha -1 for the IC system and 0, 22, and 45 kg N ha -1 for the SW-F system. Annual precipitation ranged from 206 to 655 mm, averaging 422 mm over 12 yr. The IC system generated higher profits than the SW-F system, but the IC profits were more variable. Within the IC system, MT generated higher profits than corresponding N treatments under CT and NT, but MT profits were more variable. Of the N rates evaluated, the largest N rates generated the largest profits. The dryland IC system with MT and NT was more profitable than the best SW-F system using CT for this location. Stochastic dominance analyses revealed that the SW-F system and IC system CT treatments were economically inefficient when compared with the IC system with MT and NT.
Colonization pattern of vancomycin-resistant Enterococcus faecium.

Abstract Background : Vancomycin-resistant Enterococcus faecium is increasingly recognized as a serious problem by hospital epidemiologists. Understanding its colonization patterns may help in designing strategies to control its nosocomial spread in the hospital. Methods : Twenty patients, selected at random, with vancomycin-resistant E. faecium isolated from cultures of various body sites were studied to determine sites of colonization. For 12 of these patients, cultures of environmental surfaces of their rooms and wards were also obtained. Results : Eighteen patients (90%) had vancomycin-resistant E. faecium grown in stool cultures. In five patients (25%), vancomycin-resistant E. Faecium was cultured from other sites: groins (four), popliteal fossae (three), mouth (one), and an open wound site (one). Patients with positive cultures from the groins and popliteal fossae also had growth of vancomycin-resistant E. faecium in cultures of diarrhea soiling those sites. No patients had the organism isolated from their nares. Vancomycin-resistant E. faecium grew in cultures obtained from bedside stand tables, over-bed tables, used linen, and bedside rails. Conclusions : In the 20 patients studied, colonization of vancomycin-resistant E. faecium was limited chiefly to the enteric tract. Absence of colonization of such a secluded area with poor antibiotic penetrability as the nares is encouraging. In our study, vancomycin-resistant E. faecium was isolated from various environmental surfaces from the rooms and wards of patients with vancomycin-resistant E. faecium in their stools.
Compelled Disclosure of Scientific Research Data

Federal legislation requires that research produced with federal funding be available to the public under the Freedom of Information Act. I raise a concern that this power might be used to harass scientists. The goal of data sharing, however, is important, and should be facilitated through electronic data archiving.
Membrane Interactions Of The Anthracycline Antibiotics

The intrinsic fluorescence properties of the anthracycline antitumor antibiotics were exploited here to study the manner in which a 14-valerate substituent modulated relative drug location and dynamics in fluid-phase bilayers at 37°C. Using Adriamycin (A), N,N-dimethyladriamycin (NDA), N-trifluoroacetyladriamycin (NTA), N-benzyladriamycin (NBA), and their corresponding valerate-substituted analogs (AD48, AD199, AD32 and AD198, respectively), the accessibilities of bound fluorophores to membrane-impermeable iodide were evaluated in quenching experiments conducted at constant ionic strength, while the diffusive motions of these agents were studied through the use of lifetime-resolved anisotropy plots. Incorporation of a bulky 14-valerate side chain into an anthracycline was found to enhance the hindered rotations experienced by a bound drug molecule, with limiting anisotropy (a.) values increasing from 0.166 to 0.258 for NTA and from 0 243 to 1 0.264 for NBA. However, the bimolecular quenching rate constants (x10 M ls ) for membrane-bound A (1.4), AD48 (1.1), NDA (1.8), AD199 (1.1), NBA (0.8), AD198 (0.7), NTA (0.4) and AD32 (0.5) indicate that the hydrophobic side chain was not, in general, a strong modulator of fluorophore penetration into the bilayer.
QuikSCAT reveals the surface circulation of the Catalina Eddy

[1] The Catalina Eddy, a small, recurring cyclonic vortex in the ocean off Los Angeles, is of keen interest to local weather forecasters because of the moderating oceanic effect it brings to the city. Its small size and shallow vertical extent have made it difficult to monitor and predict using conventional data. The microwave scatterometer on the QuikSCAT spacecraft has generated high-resolution surface wind vectors that provide the first visualization of the complete cyclonic flow of the eddy. Moreover, the superior performance of the QuikSCAT scatterometer demonstrates the relative inaccuracy and inconsistency of predictions of the eddy based upon numerical weather prediction models.
Cholinergic role on release and action of motilin.

Abstract In conscious dogs with gastric fistula and platinum electrodes on the antrum, duodenum and jejunum, IV atropine 100 μg/kg/hr and hexamethonium 10 mg/kg/hr, blocked cyclic increases in fasting plasma motilin concentration (PMC) and spontaneous migrating myoelectric complexes (MMCs) of both antrum and duodenum. The two drugs also blocked occurrence of premature MMCs produced by synthetic porcine motilin. In anesthetized dogs, electrical stimulation of cervical vagi with stimulation parameters; 9V, 10 c/s, 5 msec, caused a significant increase in both portal and femoral venous PMC which was blocked by atropine. Fractionations of vagus nerve extracts by gel filtration using Sephadex G-50 superfine column revealed most of motilin-like immunoreactivity (MLI) with the same mobility as pure porcine motilin. Studies suggest that cholinergic influence plays a significant role on release of motilin.
Inheritance Analysis of Congenital Left Ventricular Outflow Tract Obstruction Malformations: Segregation, Multiplex Relative Risk, and Heritability

The left ventricular outflow tract (LVOTO) malformations, aortic valve stenosis (AVS), coarctation of the aorta (COA), and hypoplastic left heart (HLH) constitute a mechanistically defined subgroup of congenital heart defects that have substantial evidence for a genetic component. Evidence from echocardiography studies has shown that bicuspid aortic valve (BAV) is found frequently in relatives of children with LVOTO defects. However, formal inheritance analysis has not been performed. We ascertained 124 families by an index case with AVS, COA, or HLH. A total of 413 relatives were enrolled in the study, of which 351 had detailed echocardiography exams for structural heart defects and measurements of a variety of aortic arch, left ventricle, and valve structures. LVOTO malformations were noted in 30 relatives (18 BAV, 5 HLH, 3 COA, and 3 AVS), along with significant congenital heart defects (CHD) in 2 others (32/413; 7.7%). Relative risk for first-degree relatives in this group was 36.9, with a heritability of 0.71-0.90. Formal segregation analysis suggests that one or more minor loci with rare dominant alleles may be operative in a subset of families. Multiplex relative risk analysis, which estimates number of loci, had the highest maximum likelihood score in a model with 2 loci (range of 1-6 in the lod-1 support interval). Heritability of several aortic arch measurements and aortic valve was significant. These data support a complex but most likely oligogenic pattern of inheritance. A combination of linkage and association study designs is likely to enable LVOTO risk gene identification. This data can also provide families with important information for screening asymptomatic relatives for potentially harmful cardiac defects.
Pseudo-(Tumor-Induced) Rickets

An athletic 8-year-old boy developed severe muscle weakness over 2 years. At the age of 10 years, investigation for possible neuromuscular disease disclosed hypophosphatemia (1.8 mg/dl) and rickets. There was selective renal tubular wasting of inorganic phosphate (Pi) but no history of toxin exposure, familial bone or kidney disease, or biochemical evidence of vitamin D deficiency. Urine amino acid quantitation was unremarkable. Serum 1,25-dihydroxyvitamin D [1,25(OH)2D] concentration was in the lower half of the reference range. Our presumptive diagnosis was tumor-induced rickets; however, physical examination and bone scanning in search of a neoplasm were unrevealing. Soon after 1,25(OH)2D3 and Pi treatment began, muscle strength improved considerably. After 6 months of therapy, radiographic abnormalities were substantially better. During the next 6 years, physical examinations, a second bone scan, whole-body and nasal sinus magnetic resonance imaging, and octreotide scintigraphy were unremarkable. When his physes fused at the age of 16 years, assessment of his course showed excellent control of his rickets requiring decreasing doses of medication. Furthermore, fasting serum Pi levels and tubular maximum phosphorus/glomerular filtration (TmP/ GFR) values had increased steadily and normalized after 3 years of treatment. Accordingly, therapy was stopped. Seven months after stopping medication, he continues to feel completely well. Fasting serum Pi levels, TmP/GFR, other biochemical parameters of bone and mineral homeostasis, creatinine clearance, and renal sonography are normal. Neither spontaneous or pharmacologic cure of tumor-induced rickets or osteomalacia nor a patient matching ours has been reported. His disorder, which we call pseudo-(tumor-induced) rickets, should be considered when investigation for oncogenic rickets or osteomalacia discloses no causal lesion. Consequently, prolonged medical therapy and futile searches for a neoplasm may be avoided.
Temporal variability of organic C and nitrate in a shallow aquifer

The loading of organic substrates into shallow aquifers may follow seasonal cycles, which will impact the transport and fate of agrichemicals. The objective of this research was to measure temporal changes in the groundwater dissolved organic C (DOC) and nitrate concentrations. Groundwater monitoring wells were installed and sediment samples from the aquifer were collected in 1991. Sediment samples were used to evaluate denitrification potentials, while water samples were collected at periodic intervals in 1992 and 1993 from the surface of the aquifer. Water samples were analyzed for nitrate-N and DOC-C. Denitrification was observed in sediment amended with nitrate and incubated under anaerobic conditions at 10°C. Addition of algae lazed biomass increased denitrification, establishing that denitrification was substrate limited. In the aquifer, DOC concentrations followed seasonal patterns. DOC concentrations were highest following spring recharge and then decreased. Peak timing indicates that freezing and thawing were responsible for seasonal DOC patterns. These findings show that seasonally driven physical processes, such as freezing and thawing, influence organic substrate transport from surface to subsurface environments, and that this process should be taken into account when assessing agrichemical detoxification rates in shallow aquifers.
Stimulation of gluconeogenesis by somatostatin in rat kidney cortex slices

Abstract The effect of somatostatin on gluconeogenesis was studied in kidney cortex slices. Addition of somatostatin (2 μg) stimulated gluconeogenesis from lactate, pyruvate and glutamine by 42%, 50% and 68% respectively. Stimulation of glucose synthesis from lactate by somatostatin was found to be linear with time and dose dependent between 0.1 and 20 μg. Somatostatin-stimulated gluconeogenesis was inhibited by phentolamine (10 μM) but not by propranolol (10 μM) suggesting that somatostatin action is mediated by α-adrenergic stimuli.
Brief Report: Validation of the Autism Reinforcer Checklist for Children

Identification of reinforcers by reinforcement checklists for use in behavioral interventions has been a starting point for a number of behavior management programs (Cautela, 1968, 1970; Cautela & Brion-Meisels, 1979; Cautela & Kastenbaum, 1967; Cautela & Wisocki, 1971; Dewhurst & Cautela, 1980). For children and adults, these identified reinforcers have been used in a variety of interventions with a variety of conditions in desensitization programs (Wolpe, 1973), in the assessment of depression (Cautela & Wisocki, 1971), in behavior management of junior high school students (Sheperd, 1981), and in the treatment of enuresis (Cautela, 1970), to name a few. The developers of reinforcement checklists, however, have failed to establish systematically the more traditional psychometric characteristics of their checklists. Test-retest reliability has rarely been reported. Additionally, the concurrent validity of a reinforcer checklist has frequently not been reported, particularly for use with special handicapped populations. Exceptions to the nonreport ing of psychometric properties of reinforcer checklists include a reinforcer checklist for normal children (Cautela & Brion-Meisels,
Identification and characterization of a brain-specific antigen enriched in neonatal brain. II. Antigenic stability, species cross-reactivity and tumor cell association.

Abstract NABSA is a brain-specific antigen enriched in neonatal brain. Microcomplement fixation was used to determine the extent of serological stability of NABSA towards heat denaturation and freeze-thaw denaturation. NABSA antigenic activity was progressively lost from neonatal and adult brain solutions incubated at temperatures above 40°C. All activity was lost above 65°C. Dilute solutions of NABSA were stable at 8°C for at least two weeks and could be frozen and thawed in Tris·phosphate buffer at concentrations above 2 mg/ml with little loss of activity. NABSA was found in every vertebrate species tested. An unusually close structural similarity (a frequent characteristic of both brain-specific antigens and fetal antigens) was demonstrated by serological methods among the mammalian and avian NABSAs. NABSA was detected by microcomplement fixation analysis in 4 out of 16 rat and murine neural clonal tumor cell lines. There was no clear limitation of NABSA to a particular class of neural cell (as defined by the phenotypes of these tumor cell classes) or to rapidly dividing or stationary phase cells. NABSA may be a brain-specific oncofetal antigen (OFA-associated), since it is present in tumor cells of the nervous system and high levels are found in immature brain.
Slipped structures in DNA triplet repeat sequences: entropic contributions to genetic instabilities.

Slipped DNA structures can occur in sequences with direct repeats. DNA triplet repeats, particularly (CTG)n, (CGC)n, and (GAA)n, are known to be associated with several neurological diseases. Slippage is probably the cause of expansion of the number of repeats, a process called dynamic mutation, which is known to be the cause of the diseased state. Here it is shown that the conformational entropy associated with slippage is more destabilizing for long direct repeats (300−1000 base pairs) than shorter runs (10−30 base pairs), by about 2 kcal/mol. This contributes to the greater instability of longer sequences. Entropic considerations also favor the formation of simple bulges, rather than hairpin structures. A model is presented for dynamic mutations, and experimentally testable predictions are made that will allow the model to be tested.
The effects of kinetic variables on the structure of copper deposits cemented on pure aluminum discs: A scanning electron microscopic study

Abstract The structural characteristics of copper deposits resulting from copper cementation on pure aluminum are presented. The effect of chloride ion concentration, rotational speed of the aluminum disc, hydrogen ion concentration, copper ion concentration, and temperature on the nature and morphology of the deposits was investigated. Different copper deposit structures, viz. bulbous, massive crystalline, thick dendrites with leaf-like secondary arms, and dendrites of different degrees of fineness and texture were observed in the present study utilizing the scanning electron microscope. Deposit morphology was greatly modified for variations of chloride ion up to 25 mg l−1 and for increases in temperature up to 40° C. The maximum rate of copper cementation on pure aluminum was usually associated with a fine, dendritic structure.
Diurnal rhythms of 5-HT1A and 5-HT2 receptor binding in euthermic and torpor prone deermice, Peromyscus maniculatus

Abstract Deermice display both spontaneous and induced daily torpor bouts, attaining minimum body temperatures of 15–20°C. There is evidence that brain serotonin may be involved in the initiation and/or maintenance of torpor. Inhibition of serotonin [5-hydroxytryptamine (5-HT)] synthesis markedly reduces the duration and depth of torpor. Because a certain percentage of deermice will not enter torpor under any circumstances, we were able to compare 5-HT receptor subtypes in deermice that readily enter into torpor (TP) and in non-torpor prone (NTP) animals. Deermice were trapped in the wild and subjected to food rationing and low ambient temperature and then sacrificed either in a normothermic or torpid state at 11:00 p.m. or 11:00 a.m. Whole brain was assayed for 5-HT 1A and 5-HT 2 receptor differences using [ 3 H]8-OH-DPAT and [ 3 H]ketanserin, respectively. The B max values for 5-HT 1A receptors were significantly greater in both TP and NTP animals sacrificed at 11:00 p.m. compared to animals sacrificed at 11:00 a.m. In contrast, the density of 5-HT 2 receptors was significantly greater in animals sacrificed at 11:00 a.m. compared to animals sacrificed at 11:00 p.m. This is consistent with the opposing functions of these receptors in the regulation of temperature and sleep. The affinity ( K d ) of each receptor was unchanged. A comparison of TP and NTP animals sacrificed at the same time of day revealed no significant differences in either B max or in K d values, indicating that differences in 5-HT 1A and 5-HT 2 receptors may not explain the heterogeneity of deermice in their ability to enter torpor. However, the diurnal fluctuation in 5-HT receptors described here may be involved in the serotonergic regulation of hormone rhythmicity and the onset of torpor in deermice.
Are different parts of the extended amygdala involved in fear versus anxiety

Although there is a close correspondence between fear and anxiety, and the study of fear in animals has been extremely valuable for understanding brain systems that are important for anxiety, it is equally clear that a richer animal model of human anxiety disorders would include measures of both stimulus-specific fear and something less stimulus specific, more akin to anxiety. Studies in patients with posttraumatic stress syndrome indicate these individuals seem to show normal fear reactions but abnormal anxiety measured with the acoustic startle reflex. Studies in rats, also using the startle reflex, indicate that highly processed explicit cue information (lights, tones, touch) activates the central nucleus of the amygdala, which in turn activates hypothalamic and brain stem target areas involved in specific signs of fear. Somewhat less explicit information, such as that produced by exposure to a threating environment for several minutes or by intraventricular administration of the peptide corticotropin-releasing hormone may activate a brain area closely related to the amygdala, called the bed nucleus of the stria terminalis, which in turn activates hypothalamic and brain stem target areas involved in specific signs of fear or anxiety. Because the nature of this information may be less specific than that produced by an explicit cue, and of much longer duration, activation of the bed nucleus of the stria terminalis may be more akin to anxiety than to fear.
Sixteenth annual AAEM Edward H. Lambert lecture. Electrodiagnostic aspects of diabetic neuropathies: Entrapments

A MEDLINE review suggested a lack of recent studies about the entrapments seen with underlying diabetic neuropathy. Suggested protocols for research in diabetic peripheral neuropathy have not included the concepts of entrapments as an early--indeed, first manifestation of the neuropathy. Carpal tunnel syndrome is a frequent accompaniment of diabetic peripheral neuropathy. Assessment of the degree of entrapment superimposed on the generalized peripheral neuropathy can be clarified by analysis of the CMAP and the SNAP--particularly with respect to duration of the negative spike of the action potential. Also, analysis of the action potentials elicited by stimulation of the ulnar and radial nerves and their comparison with the median nerve is often helpful. Finally careful inspection of the action potential when stimulating proximal and distal to the entrapment will establish the degree of nerve compromise relative to the underlying diabetic neuropathy.
Evaluation of canine left ventricular contractility

After exposure of the hearts of eight dogs to a total of 45 min of myocardial ischaemia during cardiopulmonary bypass, mean left ventricular hydraulic output power (MLVP) decreased to an average of 49·5% of the original value and Vmax to 95·2% of its original value. During a constant intravenous infusion of isoproterenol, MLVP and Vmax expressed as a percentage of the depressed value noted after ischaemia, increased to an average of 229 and 164%, respectively. During epinephrine infusion MLVP and Vmax increased to an average of 171 and 123%, respectively, relative to the post-ischaemic levels. MLVP was shown to quantitate practically all of the mechanical output power of the left ventricle. Thus, if preload, afterload, and heart rate are controlled, MLVP should be representative of the contractile state of the left ventricle. Since changes of Vmax in response to positive and negative inotropic intervention did not correlate with MLVP, we concluded Vmax did not accurately reflect quantitative change of the contractile state of the left ventricle.
Apoptosis staining in cultured pseudoachondroplasia chondrocytes

Pseudoachondroplasia (PSACH) is a skeletal dysplasia caused by a mutation in cartilage oligomeric matrix protein (COMP), a glycoprotein of normal cartilage matrix. PSACH chondrocytes have a distinctive phenotype with enlarged rER cisternae containing COMP, aggrecan, type IX collagen, and chaperone proteins. Ultrastructural studies suggested that this accumulation compromises cell function, hastening cell death, and consequently reducing the number of cells in the growth plate contributing to linear bone growth. Using the alginate bead system, we cultured control and PSACH chondrocytes for twenty weeks and one year to determine the effect of the mutation on size and number of cartilage nodules; and the presence of apoptotic cell death (TUNEL assay). At 20 weeks, beads containing PSACH or control chondrocytes did not differ in size and number of cartilage nodules or number of TUNEL-positive cells. After one year, nodule number, size and percent cartilage per bead were significantly less in PSACH nodules, and the number of cells staining positive for apoptosis was significantly greater than in controls (71.8% vs. 44.6%). The increase in apoptosis in PSACH nodules correlates with a decrease in growth of cartilage, supporting our hypothesis that death of damaged cells contributes to the growth plate defects in PSACH.
Diagnostic approach to children with birth defects.

Clinical genetics deals with the diagnosis, manage ment and prevention of genetically determined disorders. Our current understanding of the role genes play in the pathogenesis of everything from fetal malformation to neurodegenerative and malignant disorders of late adulthood make it somewhat difficult to draw a clear boundary for this rapidly expanding specialty. With the recent completion of a preliminary draft of the entire sequence of the human genome it is not unreasonable to dream of novel therapeutic approaches such as “gene therapy”, to cure disorders heretofore treatable with supportive measures only. Nevertheless, the clinical assessment of the patient will continue to be the cornerstone of good practice of medicine. In this article we review a clinical approach to the diagnostic challenge presented by children with birth defects. The principles we illustrate apply to other aspects of “genetic medicine” as well.
Reynolds analogy in combustor modeling

Abstract The Reynolds analogy concept has been used in almost all turbulent reacting flow RANS (Reynolds-averaged Navier–Stokes) simulations, where the turbulence scalar transfers in flow fields are calculated based on the modeled turbulence momentum transfer. This concept, applied to a diffusion flame model combustor, is assessed in this paper. Some of the numerical results, obtained from a flamelet combustion model with the turbulent Prandtl/Schmidt number varying from 0.25 to 0.85, are presented and compared with a benchmark experimental database. It is found that the turbulent Prandtl/Schmidt number has significant effects on the predicted temperature and species fields in the combustor. This is also true for the temperature profile along the combustor wall. In contrast, its effect on the velocity field is insignificant in the range considered. With an optimized turbulent Prandtl/Schmidt number, both velocity and scalar fields can be reasonably and quantitatively predicted. For the present configuration and operating conditions, the optimal Prandtl/Schmidt number is 0.5, lower than the traditionally used value of ∼0.85. This study suggests that for accurate prediction of turbulence scalar transfers in practical reacting flows, the Reynolds analogy concept should be improved and new approaches should be developed.
Simultaneous testing of parameter subsets in less than full rank models

If the experimental design (or lack of design) results in a nodel which is not of f u l l rank, the problem of variable selection becomes rather complex. Tkis is due to the fact that, in less than f u l l rank models, not every linear combination of regression parameters is estimable. In this paper, we present a procedure fortesting all “testable” subsets of a complete set of regression parameters, using a technique based on Scheffe's method (1959). A class of “adequate” subsets of regression parameters is obtained in a manner similar to that of Aitkin (1974). The proposed procedure is illustraced with an example.
Full-Wave Seismic Data Assimilation: Theoretical Background and Recent Advances

The seismological inverse problem has much in common with the data assimilation problem found in meteorology and oceanography. Using the data assimilation methodology, I will formulate the seismological inverse problem for estimating seismic source and Earth structure parameters in the form of weak-constraint generalized inverse, in which the seismic wave equation and the associated initial and boundary conditions are allowed to contain errors. The resulting Euler–Lagrange equations are closely related to the adjoint method and the scattering-integral method, which have been successfully applied in full-3D, full-wave seismic tomography and earthquake source parameter inversions. I will review some recent applications of the full-wave methodology in seismic tomography and seismic source parameter inversions and discuss some challenging issues related to the computational implementation and the effective exploitation of seismic waveform data.
Critical Tractions for Initiating Adhesion Failure at Interfaces in Encapsulated Components

Determining the initiation of adhesive failure at a surface buried deep within the bulk of an epoxy is qualitatively different from measuring the propagation of an existing surface crack. Most current tests are shown to be unsuitable for assessing the critical traction at initiation. A new test geometry is presented that initiates failure away from an air interface, produces a slowly varying stress distribution near the initiation site and minimal contributions from thermal residual stresses, and enables tests with mixed modes of loading. This new geometry is used to examine temperature-dependent adhesive failure in tensile, shear, and mixed modes of loading for both smooth and rough surfaces. Some of the experimental results are unexpected. As examples, the critical traction at initiation of adhesive failure is apparently insensitive to surface roughness, and the critical normal traction is independent of temperature while the critical tangential traction tracks the shear yield stress.