cssi/SciSciGPT-SciSciNet huggingface dataset:
Prospective evaluation of a primary laparoscopic approach for children presenting with simple or complicated appendicitis.

Abstract Background Previous studies have suggested laparoscopy leads to an increased risk of postoperative intra-abdominal abscess formation in complicated appendicitis. The purpose of this study is to prospectively evaluate a standardized laparoscopic approach applied by a single surgeon for all children who present with appendicitis and to determine the postoperative outcome. Methods Over a 5-year period (2001-2005), all children presenting to the author with simple or complicated appendicitis were approached laparoscopically and their preoperative workup, intraoperative findings, and postoperative outcomes recorded. Results One hundred seventy-five consecutive laparoscopic appendectomies were performed with no open conversions. Mean patient age was 9 years. Sixty-seven patients (38%) presented with complicated appendicitis. The overall complication rate was 6% (9 children developed a postoperative intra-abdominal abscess or phlegmon and 2 had umbilical wound infections). Conclusions When laparoscopic appendectomy is used as the primary technique, only 6% of patients experience infectious complications. Therefore, a laparoscopic approach to all children presenting with appendicitis does not lead to an increased complication rate.
Where's the money? Inversions, genes, and the hunt for genomic targets of selection.

> In this commentary, Kirkpatrick and Kern discuss [Cheng et al.][1], “Ecological genomics of Anopheles gambiae along a latitudinal cline: a population-resequencing approach,” which is published in this issue of GENETICS. Legend has it that, when asked why he robbed banks, Willie Sutton replied
Pseudotumor cerebri in children with Down syndrome.

Purpose To report 4 pediatric Down syndrome patients with optic nerve elevation and pseudotumor cerebri. Design Retrospective observational case series. Participants Four pediatric Down syndrome patients found to have optic nerve elevation on ophthalmologic examination at a single institution. Methods Medical record review of 117 pediatric Down syndrome patients aged 0 to 18 years was performed. All patients were seen at the University of Wisconsin pediatric ophthalmology clinic between 1995 and 2005. Main Outcome Measures Visual acuity, optic nerve appearance, and neurologic work-up. Results Four (3.4%) of 117 Down syndrome patients seen at the university's pediatric ophthalmology clinic were found to have optic nerve elevation. This included 2 boys and 2 girls, aged 2 to 10 years. None of the patients had a history of headache or transient visual obscuration. One of the patients had high hyperopia at the time of presentation, and all were referred for neurologic evaluation of suspected increased intracranial pressure. Three patients were diagnosed with pseudotumor cerebri (PTC) based on a normal brain magnetic resonance imaging (MRI) scan, an elevated opening cerebrospinal fluid (CSF) pressure on lumbar puncture, and normal CSF analysis results. The fourth patient's elevated optic nerve appearance was likely secondary to PTC after obtaining normal brain MRI results; however, this patient did not undergo a lumbar puncture. One child with PTC demonstrated improvement in visual acuity and optic nerve appearance after acetazolamide and weight loss therapy. The 2 additional patients with PTC were treated with either low-dose acetazolamide or weight loss therapy and experienced optic atrophy. The final patient, who did not undergo lumbar puncture, experienced spontaneous resolution of optic nerve elevation. Mean follow-up duration was 49 months. Conclusions Only 3.4% (4/117) of Down syndrome children were found to have optic nerve elevation in a single institution. Pseudotumor cerebri should be considered in asymptomatic Down syndrome patients with elevated optic nerves. Medical therapy in PTC with acetazolamide can lead to improvement in visual acuity and optic nerve appearance, although optic atrophy also was seen.
Ultrastructure of the frontal organ in Convoluta and Macrostomum spp.: significance for models of the turbellarian archetype

Present models of turbellarian evolution depict the organism with a frontal organ — a complex of glands whose necks emerge at the anterior tip of the body — and therefore imply that this organ is homologous throughout the Turbellaria. However, comparisons of representatives of the Acoela and Macrostomida, two putatively primitive orders of the Turbellaria, show that frontal organs in these two are not similar in ultrastructure or histochemistry. The acoel Convoluta ‘pulchra’ had a prominent cluster of frontal mucous glands whose necks emerged together in a frontal pore at the exact apical pole of the organism, and an array of smaller glands of at least five other types opened at the anterior end, separately from and ventral to this pore. The ‘frontal organs’ (Stirndrusen) of two species of Macrostomum on the other hand, comprised an array of discretely emerging necks of at least two gland types including one with rhabdiform (rhammite) and one with globular mucous secretion granules neither of which emerge at the apical pole. In neither species did the organ appear to be sensory. Our findings indicate a low probability of homology between the frontal glands of the Acoela and Macrostomida.
Effects of mutations at position 36 of tRNAGlu on missense and nonsense suppression in Escherichia coli

Mutations in the anticodon of tRNA Clu (UUC) were isolated or constructed and characterized for their ability to sup- press cognate nonsense or missense mutations in vivo. The C36- to-A36 transversion mutation was isolated as an ochre and an amber suppressor, while the G36 transversion was selected as a CAG missense suppressor, tRNA G~u suppressors of an AAG mis- sense mutation could not be isolated, and a 1536 transition muta- tion introduced into tRNA G~u in vitro conferred no suppressor phenotype. Over-expression of glutamyl-tRNA synthetase did not increase the activity of the U36 mutant tRNA clu, suggesting a defect at the level of translation rather than at the level of synthetase recognition.
Variations in magma source regions during large-scale continental extension, Death Valley region, western United States

Abstract Extension in the Death Valley region proceeded in two phases: a rapid extensional phase between ∼ 12 and 5 Ma and a slow phase between 5 Ma and the present. During the early rapid phase the Nd isotopic composition of rift-related mafic igneous rocks changed from high ϵ Nd ( ∼ −1) values at 12 Ma to low ϵ Nd ( ∼ −10) values at 5 Ma. This is opposite to what would be expected if the shift in the source of rift magmas was in response to simple thinning of the lithosphere, as has been suggested by previous models. The Nd and Sr isotopic variations suggest that the sources of the rift-related magmas changed from a source with possibly a relatively large asthenospheric component during the early rapid phase of extension to enriched lithospheric mantle during later slow extension. Assuming predominantly vertical magmatic transport, the Nd isotopic trend observed in the Central Death Valley volcanic field may indicate a relationship between rates of extension and variation in magma sources. The high ϵ Nd (depleted) component in the early magmas may reflect greater ease of penetration of the lithosphere by asthenospheric magmas while extension was rapid, while later enriched basalts were derived from overlying, old lithospheric mantle once extension slowed. Alternatively, a model with lateral flow of a fluid crustal layer during early extension may have forced asthenosphere melts derived from source regions under the Sierra Nevada eastward, interposing them between enriched lithospheric mantle and upper crust. Subsequently, late rift magmas would be derived mainly from the underlying enriched lithospheric mantle. Many previous estimates of mantle addition to continental crust have taken depleted mantle values as end-member estimates for the mantle component. However, the lithospheric mantle has isotopic and trace element characteristics similar to the continental crust. Accordingly, mantle addition in continental rifts may be much larger than previously estimated.
Impact of stage hypnosis.

The purpose of this study was to assess the impact of a performance by a stage hypnotist on a university campus. We used two approaches to evaluate the effects: a random telephone survey of the student population, and face-to-face interviews with individuals who were in trance during the performance. These two approaches gave us the opportunity to study and to compare the characteristics and reactions of both the hypnotic subjects on the stage and the members of the audience. We found that about half of the individuals who had a trance experience generally enjoyed it and had some positive aftereffects. About one-fifth of the trance subjects had both a negative experience during the trance and some negative aftereffects. Stage hypnosis, although it is presented as mere entertainment, appears to have both positive and negative effects on a significant number of people. A number of factors contribute to its potential dangers. Stage hypnosis poses risks that are unacceptable and outweigh its potential enterta...
Exploring the Emergence of Virtual Human Resource Development

Technology is permeating our personal and professional lives and is having an enormous impact on the field of human resource development (HRD). Given the growing interest that scholars have had for...
Clinical Evaluation of Two Types of Resilient Liners on Dentures

Craig R. Means, DDS, MSc Nelson W. Rupp, DDS, MS George C. Paffenbarger, DDS, Washington, DC This paper reports clin ical observations made on 14 patients who wore 23 dentures. The dentures were lined with either Coe Super Soft or Silastic 616 re­ silient liners. Observations that were made during the 21-month study led to the following conclu­ sions. ■ Both materials are safe to use against oral t is ­ sues. ■ Because deterioration and loss of resilience reduce their effectiveness in a short time, dentures lined with these materials should be observed every three months. ■ The border junction between the resilient lin ­ er and the denture base should be a butt joint. A thin tapered junction is unsatisfactory. The finish line should be well away from the borders of the flanges. ■ These resilient liners should be considered as temporary expedients, to be used only in selected cases that require a protective resilient surface on the tissue-bearing side of the denture base. A denture with a resilient liner should be su ffi­ c iently th ick in cross section to resist fracture. Thinning the denture to accommodate a resilient liner may lead to fracture in sen/ice.
Mechanisms of Alemtuzumab-Mediated Cytotoxicity in Hematologic Malignancies

Abstract Monoclonal antibodies offer a focused therapeutic approach for solid and hematologic malignancies. Alemtuzumab is a chimeric monoclonal antibody that targets the CD52 antigen on normal and malignant lymphoid cells and is approved for the treatment of patients with relapsed chronic lymphocytic leukemia. Its main mechanistic cell-killing effects include complement-dependent cytoxicity, antibody-dependent cell-mediated cytotoxicity, and apoptosis. Ongoing investigation into the relative importance of these cytotoxic pathways is necessary for improved understanding of the mechanisms of action by which alemtuzumab and other monoclonal antibodies exert their beneficial antitumor activity in vivo.
Origins of brain tumors--a disease of stem cells?

The hypothesis that brain cancer might arise from a small population of cancer stem cells has received much attention in recent years. In this Viewpoint, however, Fomchenko and Holland argue that brain tumorigenesis might be more complex than this. They suggest that many of the stem-like cells found in brain tumors might have been recruited from surrounding tissues, and they discuss the implications for cancer therapy.
Laboratory Studies on Effects of Temperature and Delayed Initial Feeding on Development of Striped Bass Larvae

Abstract Rearing temperature and the time of first feeding interacted to determine the degree of survival and rate of growth of larval striped bass (Morone saxatilis) in laboratory experiments. Between 15 and 24 C, lower temperatures reduced the rate of growth and development of fed larvae, and increased the time to death by starvation of unfed larvae. Striped bass larvae survived for several weeks without food following yolk absorption. Unfed groups survived up to 22 days after hatching at 24 C and 32 days at 15 C. Although unfed larvae decreased in length and dry weight during starvation, many recovered and continued development after food was provided. Among starved larvae the rate of loss in weight and length increased with increasing temperature. The growth rate among early and delayed feeding groups was also temperature related. Larvae that survived delayed feeding were indistinguishable on the basis of size and external morphology from younger but well-fed individuals. It is suggested that size alo...
Composite electrodes for electroanalysis: Principles and applications

A composite electrode has a surface that consists of an ordered arrangement (array) or a random arrangement (ensemble) of conductor regions, typically micrometers in dimension, separated from one another by an insulator. These active regions (or microelectrodes) may themselves be of regular geometry and confined primarily to the surface, as with most array electrodes, or of irregular geometry and permeate the bulk of the material, as with most ensemble electrodes. In this review, we classify composite electrodes according to the distribution of a conductor and insulator within the material (or on the surface), survey a number of the fabrication schemes used to construct composite electrodes, discuss percolation theory as it applies to certain composite electrodes, examine the surface morphology of selected composite materials, discuss the origins of the enhancement in current density observed at many composite electrodes in both quiescent and flowing solutions, and provide a few examples illustrating the applications of composite electrodes to real analytical problems.
"Bad" mothers : the politics of blame in twentieth-century America

In the past quarter century, "bad" mothers have moved noticeably toward center stage in American culture. While Susan Smith will eventually fade from the tabloids, the monster mother that she represents has a storied and long history. Mothers have been blamed for a host of problems, from autism in children (due to chilly "refrigerator" mothers), to homosexuality (attributed to "smothering" moms), to welfare dependency and crime (caused by black "matriarchs" and single mothers). Some mothers are not good mothers. No one can deny that. There are women who neglect their children, abuse them, and fail to provide them with proper psychological nurturance. While such mothers have always stimulated the American imagination, the definition of what constitutes a bad mother has expanded significantly in recent years. Indeed, with a distinct minority of American families living the two-parent, one-worker lifestyle once considered the norm, we all face the discomfiting question, Do most mothers now qualify as "bad" mothers in one way or another? Drawing together the work of prominent scholars and journalists, "Bad" Mothers considers such diverse topics as the mother-blaming theories of psychological and medical "experts," bad mothers in the popular media, the scapegoating of mothers in politics, and the punitive approach to "bad" mothers by social service and legal authorities. The volume also includes the stories of individual "bad" mothers, from sterilization survivor Willie Mallory to rock star Courtney Love. Ably edited by two leading scholars, "Bad" Mothers marks an important contribution to the literature on motherhood.
Proton magnetic resonance studies of lipid bilayer membranes Experimental determination of inter- and intramolecular nuclear relaxation rates in sonicated phosphatidylcholine bilayer vesicles

Abstract We have determined the relative magnitudes of the intra- and intermolecular contributions to the nuclear magnetic relaxation rates of the methylene protons of the hydrocarbon chains in phosphatidylcholine bilayer vesicles over a range of temperatures and at two NMR frequencies (100 and 220 MHz). These measurements have been made by the isotopic dilution method using deuterated phosphatidylcholines containing fully deuterated hydrocarbon chains. The results showed that both the methylene linewidths and the spin-lattice relaxation rates are dominated by intramolecular dipolar interactions. Both the intra- and intermolecular contributions to the spin-lattice relaxation rate were found to decrease with increasing temperature and to exhibit a frequency dependence, the rates being higher at the lower NMR frequency in both cases. These observations indicate that both intra- and intermolecular dipolar interactions are modulated by anisotropic motions. In the case of the intermolecular dipolar fields, it is proposed that they are modulated both by the rapid rotational isomerization of the hydrocarbon chains as well as by lateral diffusion of the lipid molecules. That the hydrocarbon chain motion must be fairly effective in effecting efficient spin-lattice relaxation is evident from the negligible intramolecular interchain contribution to the relaxation found in the present work.
Complications of small-carrion penile prosthesis

Seventy-six patients with impotence have undergone insertion of the Small-Carrion penile prosthesis at Duke University Medical Center. Twenty patients experienced postoperative complications. Seven of these 20 patients lost one or both prostheses either by spontaneous extrusion or surgical removal. Although success with this procedure is well documented, complications may be significant when they occur and awareness of these problems is essential for proper management. The benefits of this procedure are reviewed, and reported complications and their management are discussed.
Beyond Thrill-Seeking: Exploring Multiple Motives for Adventure Participation

Psychological literature on adventure has generally focused on excitement or thrillseeking motives. However, while some adventure activities are of relatively short duration (e.g., sky diving) and are reputed to be â€œrisk focused and adrenaline fuelledâ€ (Brymer, Downey, & Gray, 2010, p. 193), others (e.g., mountain climbing) are of longer duration and require considerable planning. These activities can reward participants with feelings of achievement and satisfaction through prolonged engagement against the natural elements and the self (Woodman, Hardy, Barlow, & Le Scanff, 2010). The development of psychological measures, such as the Sensation-Seeking Scale (Zuckerman, 1971) and Telic Dominance Scale (Murgatroyd, Rushton, Apter, & Ray, 1978), have influenced the design and focus of adventure research (e.g., Cogan & Brown, 1999; Freixanet, 1991; Kerr, 1991). These studies, while informative, were limited to examining thrill or arousal-seeking dimensions of motivation and failed to consider other possible adventure participation motives. As a result, a gap in the literature developed which has only recently been addressed. Qualitative studies have found that adventure motivations may extend beyond thrill-seeking to include motives such as relationships with nature, self-mastery, negative affectivity, and escape self-awareness (e.g., Brymer et al., 2010; Castanier, Le Scanff, & Woodman, 2010; Varley, 2011). Brown and Fraser (2009) also debate the centrality of risk as a motive in educational adventure activities by observing that de-emphasizing risk can enhance teaching and learning opportunities in adventure settings. These collective findings suggested the need for further investigations of adventure participation motives.
Transmission of low-intensity vibration through the axial skeleton of persons with spinal cord injury as a potential intervention for preservation of bone quantity and quality.

Background/objective: Persons with spinal cord injury (SCI) develop marked bone loss from paralysis and immobilization. Low-intensity vibration (LIV) has shown to be associated with improvement in bone mineral density in post-menopausal women and children with cerebral palsy. We investigated the transmissibility of LIV through the axial skeleton of persons with SCI as an initial approach to determine whether LIV may be used as a clinical modality to preserve skeletal integrity. Methods: Transmission of a plantar-based LIV signal (0.27 ± 0.11 g; 34 Hz) from the feet through the axial skeleton was evaluated as a function of tilt-table angle (15, 30, and 45°) in seven non-ambulatory subjects with SCI and ten able-bodied controls. Three SCI and five control subjects were also tested at 0.44± 0.18 g and 34 Hz. Transmission was measured using accelerometers affixed to a bite-bar to determine the percentage of LIV signal transmitted through the body. Results: The SCI group transmitted 25, 34, and 43% of the LIV signal, and the control group transmitted 28, 45, and 57% to the cranium at tilt angles of 15, 30, and 45°, respectively. No significant differences were noted between groups at any of the three angles of tilt. Conclusion: SCI and control groups demonstrated equivalent transmission of LIV, with greater signal transmission observed at steeper angles of tilt. This work supports the possibility of the utility of LIV as a means to deliver mechanical signals in a form of therapeutic intervention to prevent/reverse skeletal fragility in the SCI population.
Differential Behavioral and Endocrinological Effects of Corticotropin-Releasing Hormone (CRH) in the Syracuse High- and Low-Avoidance Rats

Abstract The Syracuse high- and low-avoidance rats, which have been selectively bred for good (SHA/Bru) or poor (SLA/Bru) avoidance learning in a two-way shuttle box, differ in emotionality. This experiment investigated the effect of corticotropin-releasing hormone (CRH), administered centrally (0, 0.1, 0.5, and 1.0 μg), on conditioned suppression and on the hypothalamic–pituitary–adrenocortical system. Three groups of animals were used: SHA/Bru rats conditioned at 0.21 or 0.43 mA and SLA/Bru rats conditioned at 0.21 mA. The results confirm those of previous studies which found that SLA/Bru rats show greater conditioned suppression than the SHA/Bru rats at the low shock intensity and that at 0.43 mA, the SHA/Bru animals acquire a level of conditioning comparable to that of the SLA/Bru animals at 0.21 mA. The results show that the nonlinear behavioral effect of CRH is independent of strain and produces comparable effects in animals of both strains, but only when level of conditioning is equated. Adrenal and plasma concentrations of corticosterone increased in all three groups of animals as a direct linear function of dose of CRH. Both greater levels of conditioning and larger amounts of CRH increase the synthesis of corticosterone more in SHA/Bru animals than in the SLA/Bru animals. Thus, genetic variation, which differentiates the behavioral and endocrinological characteristics of these animals, shows that these effects of CRH can be independent of each other and suggests that some minimal level of conditioned fear is necessary for CRH to exert its anxiogenic effect.
Involucrin cross-linking by transglutaminase 1. Binding to membranes directs residue specificity.

Abstract The transglutaminase 1 (TGase 1) enzyme is essential for the assembly of the cell envelope barrier in stratified squamous epithelia. It is usually bound to membranes, but to date most studies with it have involved solution assays. Here we describe anin vitro model system for characterizing the function of TGase 1 on the surface of synthetic lipid vesicles (SLV) of composition similar to eukaryote plasma membranes. Recombinant baculovirus-expressed human TGase 1 readily binds to SLV and becomes active in cross-linking above 10 μm Ca2+, in comparison to above 100 μm in solution assays, suggesting that the membrane surface is important for enzyme function. Involucrin also binds to SLV containing 12–18% phosphatidylserine and at Ca2+ concentrations above 1 μm. In reactions of involucrin with TGase 1 enzyme in solution, 80 of its 150 glutamines serve as donor residues. However, on SLV carrying both involucrin and TGase 1, only five glutamines serve as donors, of which glutamine 496 was the most favored. As controls, there was no change in specificity toward the glutamines of other substrates used by free or SLV-bound TGase 1 enzyme. We propose a model in which involucrin and TGase 1 bind to membranes shortly after expression in differentiating keratinocytes, but cross-linking begins only later as intracellular Ca2+levels increase. Furthermore, the data suggest that the membrane surface regulates the steric interaction of TGase 1 with substrates such as involucrin to permit specific cross-linking for initiation of cell envelope barrier formation.
Diagnosis. II. Diagnostic models based on attribute clusters: a proposal and comparisons.

Abstract A new discrimination procedure based on the formation of clusters of dependent attributes, and estimation of the joint probability distribution as the product of the probabilities of the disjoint clusters is proposed and investigated. The major advantages of this method are a substantial reduction of the number of probability estimates that must be made, the ability to include symptom dependencies, and the ease and flexibility of its implementation. Comparisons with other discrimination procedures are obtained using Monte Carlo techniques. Results indicate that the proposed model is robust and may lead to gains over the independence and actuarial models, especially for small sample sizes.
CHILD CARE ATTITUDES AND ADAPTATION TO THE MATERNAL ROLE AMONG MENTALLY ILL AND WELL MOTHERS

Discharged psychiatric hospital patients who were mothers of young children were compared with a group of well mothers on child rearing attitudes and adaptation to adult social roles. Mentally ill mothers were found to believe less in the importance of developing a reciprocal mother-child relationship or in differentiating between own needs and those of child, and were more likely to deny ambivalent feelings regarding child care. In each group, less adaptive child-care attitudes were related to greater impairment in adapting to other adult roles.
‘Anti–Mini Militants Meet Modern Misses’: Urban Style, Gender and the Politics of ‘National Culture’ in 1960s Dar es Salaam, Tanzania

This essay examines a 1968–9 campaign by Tanzania’s ruling party Youth League to outlaw mini–skirts and other ‘indecent’ fashions as ‘decadent’ affronts to Tanzanian ‘national culture’. It situates the intense, public debate on the campaign both in terms of the state’s contested national cultural project, and in relation to intersecting anxieties about shifts in women’s work and mobility in urban space, and the politics of sex in postcolonial Dar es Salaam. Arguing that ‘the city’ ndash; both as an imagined space and as the site of particular, gendered social struggles – is central to understanding the campaign, the essay charts attempts by the ban’s opponents to fashion viable personas and notes the limits of these attempts.
SU‐E‐T‐284: Conversion of Computational Phantom to DICOM CT Images to Be Used in a Treatment Planning System for Epidemiologic Dose Reconstruction Studies

Purpose: To develop and verify a novel method of converting surface‐based deformable hybrid computational phantom into DICOM CT images, which can be readily imported into a treatment planning system (TPS). We intended to use the technique to reconstruct doses for organs located within or near to the treatment field to support epidemiologic study of late effect in patients who received radiotherapy many years ago without volumetric imaging. Methods: We generated 352 axial images from an adult hybrid computational phantom with the in‐plane resolution of 1 mm2 and 5 mm slice thickness. All of the 78 different tissue densities of the phantom were converted into Hounsfield Units (HU) using the CT‐to‐density conversion table. In‐house MATLAB code was written to generate DICOM format images with header from the matrix of HU. We imported the generated images into Eclipse TPS (Varian, Palo Alto, CA), verified the conversion process by comparing organ volumes and densities between the original phantom and the imported images, and illustrated a simulation of a seven‐field 3D conformal prostate treatment. Results: Between the original phantom and its CT images imported in Eclipse, there were less than 2% difference in volumes and densities after automatic segmentation of the selected organs. Illustrative three‐dimensional dose distribution for prostate tumor volume and normal tissues were calculated from the TPS using the converted CT numbers. Conclusion: To reconstruct normal tissue doses for late effects studies, we established a technique to convert hybrid computational phantoms to DICOM CT images compatible with a commercial TPS. With the flexibility of the hybrid phantom that can be deformed to match patient size, our new dose reconstruction method will enable us to estimate dose distribution for the patients whose volumetric images are not available.
Nitrogen cycling and tile drainage nitrate loss in a corn/soybean watershed

Abstract Nitrogen (N) in surface waters has been linked to agricultural crop production, and more specifically, to NO3− exported by tile drainage. The objective of this study was to evaluate agricultural N pools and fluxes in a seed corn/soybean (Zea maize L./Glycine max L.) watershed (40 ha) to relate soil inorganic N pools with annual losses of NO3− in drainage tiles. During a 2-year period beginning in October 1993, soil samples in the top 50 cm located near the tile systems (predominantly Drummer silty clay loam, fine–silty, mixed mesic Typic Haplaquolls) were analyzed for microbial biomass C and N, inorganic N, and N mineralization rates. Water flow and NO3− concentrations were continuously measured in the three drainage tiles. Soil microbial biomass N ranged from 83 to 156 kg N ha−1, and appeared more closely related to soil moisture than soil inorganic N pools. Soil inorganic N ranged from a low of 13 kg N ha−1 during the soybean growing season to a high of 115 kg N ha−1 after N fertilization. Following good growing seasons in 1993 and 1994, high crop uptake of N resulted in relatively small soil inorganic N pools of 40 and 24 kg N ha−1, respectively, after crop harvest. In 1995, however, when poor growing conditions decreased crop N accumulation, 98 kg N ha−1 remained in the watershed after harvest. Based on an average effective drainage area of 30 ha, 38 and 64 kg N ha−1 leached out of the watershed through tile drainage for a total of 3.1 Mg N for the 1995 and 1996 water years, respectively. Tile N export from the watershed was greatest during high flow events when there concurrently existed large pools of soil inorganic N in the form of NO3−. Differences in annual N export for each tile were the result of a combination of factors including; timing and area of N fertilization, amount and distribution of precipitation, crop uptake of soil derived N, and inorganic N pools remaining after harvest.
Effects of oral vanadyl treatment on diabetes-induced alterations in the heart GLUT-4 transporter.

Vanadyl sulfate was administered orally during a 10-week trial period to streptozotocin-diabetic and control male rats to test the hypothesis that chronic vanadyl supplementation would prevent the decline in cardiac muscle cell glucose transporter protein (GLUT-4) that otherwise manifests in conjunction with insulin deficiency. Isolated cardiac myocytes and cardiac sarcolemmal vesicles were prepared from heart tissue of rats that had been maintained on the following regimens: untreated control, oral vanadyl-supplemented control (0.6 mg/ml), untreated diabetic (streptozotocin-induced; 60 mg/kg), and vanadyl-supplemented diabetic. Myocytes isolated from untreated diabetic rat hearts had decreased rates of glucose oxidation. Chronic, oral administration of vanadyl to diabetic rats maintained glucose oxidation rates of cardiac myocytes at control levels. Immunoblot analyses revealed that total cardiac myocyte and sarcolemmal GLUT-4 glucose transporter protein levels were significantly lower in the diabetic group relative to control. Vanadyl treatment of diabetic rats produced a normalization of both sarcolemmal GLUT-4 and total cardiac myocyte levels towards control levels. The reduction of GLUT-4 mRNA levels seen with untreated diabetes was also completely prevented with vanadyl treatment. These results demonstrate that chronic-oral vanadyl sulfate supplementation limits the decline in glucose oxidative capacity of cardiac myocytes that otherwise manifests in the untreated diabetic state. This action of vanadyl may occur via a mechanism that is linked to the preservation of sarcolemmal GLUT-4 protein levels.
Apolipoprotein E-rich HDL in patients with homozygous familial hypercholesterolemia.

Abstract Ordinarily, HDLI, a fraction of HDL enriched in apoE, is a minor fraction of plasma, but in human subjects and experimental animals eating diets high in fat and cholesterol and in patients with homozygous familial hypercholesterolemia (HFH) or CETP deficiency, HDL 1 (or HDL c ) concentrations in plasma are increased. However, little is known about the structures, compositions and metabolic sources of HDLI in HFH patients. To obtain HDL 1 for the study, we surveyed several fractions in the HDL density range for apoE by SDS-PAGE. The ratio of apoE to apoAI in the HDL ( d = 1.063–1.21 g/ml) of 8 HFH patients was 0.14 ± 0.03 compared to 0.03 ± 0.005 in a control group of 8 normolipidemic subjects ( P d = 1.020–1.050 g/ml and d > 1.090 fractions contained very little apoE. Therefore, we further characterized the d = 1.050–1.090 g/ml lipoproteins of HFH patients and controls. Fractionation of an d = 1.050–1.090 fraction by concanavalin-A chromatography (CONA) yielded an unbound apoE-rich fraction that contained apoE, apoAI and apoC but no apoB, and a bound LDL-like fraction that contained mostly apoB-100, as determined by SDS-PAGE and by solid phase immunoassays, containing monoclonal antibodies directed against apoB, apoE and apoAI. The apoEapoAI ratio of the CONA unbound fraction of HFH patients was greater, and the fraction also contained more free cholesterol and phospholipids than the fraction of control subjects. The diameters of these HDL 1 particles, determined by nondenaturing gradient gel electrophoresis, ranged from 12.2 to 17 run. HDL 1 of HFH patients were slightly larger than HDLI of controls. HDLI particles associated with and were degraded by cultured normal human skin fibroblasts with higher affinity than the LDL-like particles that were bound to the CONA column. Thus, in the composition and metabolic behavior HDL 1 isolated from the plasma of a fasted HFH patient resembled the HDL 1 (or HDL c ) seen in animals fed diets enriched in cholesterol and fats.
Bistable Behavior of ALOHA-Type Systems

Packet switching has found widespread application in computer communications because of its ability to efficiently handle high ratios of peak-to-average data rate. Packet radio is the application of packet switching techniques to radio channels. The resultant multiple-access problem requires novel approaches. Such approaches have been developed by others and have primarily been analyzed in steady-state behavior. This paper demonstrates and analyzes an important aspect of the dynamic characteristics of packet radio, namely, that of bistable behavior. That is, the system possesses two statistically stable equilibrium points, one in a desirable low-delay region, and the other in an undesirable high-delay region. Since the stability is only statistical in nature, the system oscillates between these two points. Even if the resultant steady-state behavior is very poor, this dynamic analysis frequently shows that system performance will be acceptable. This is due to quiet periods (such as at night) which allow the system to recover.
Infection with Chlamydia pneumoniae as a cause of coronary heart disease: the hypothesis is still untested

We are convinced that Chlamydia pneumoniae research has been unfavorably affected by the negative results of antibiotic treatment trials for the secondary prevention of late-stage coronary heart disease (CHD) (O'Connor et al. , 2003; Cannon et al. , 2005; Grayston et al. , 2005). There is a widespread belief that the clinical trials showed that C. pneumoniae has no role in atherosclerotic disease. This flawed causal inference from these trials has contributed to slowing much-needed research on C. pneumoniae. It has also resulted in a nearly complete loss of momentum for research on the infection-based response to injury hypothesis as a key factor in the initiation and progression of CHD. ### Box 1 Chlamydia pneumoniae had been considered a possible cause of atherosclerosis. That antibiotics failed to prevent secondary coronary events in patients with established coronary artery disease has been erroneously interpreted as ruling out a causative role for C. pneumoniae . This misinterpretation has had a chilling effect on C. pneumoniae research. Our concern has been confirmed by the sharp drop in published reports (PubMed citations) on C. pneumoniae since 2005. From 1999 to 2005, approximately 375 papers were published each year. There has been a 62% drop from that number with 143 being listed for 2013. The antibiotic treatment trials were not etiologic studies. No inference regarding the role of C. pneumoniae in the cause of atherosclerosis can properly be made from the trials. A prior publication stated that the study design for these trials precluded proving or disproving a role for C. pneumoniae in the initiation or progression of atherosclerosis, and predicted an overreaction to either negative or positive results (Grayston 2000). All subjects of these trials had established coronary artery disease with mostly advanced disease. Most had had a myocardial infarction (MI). The trials studied whether antibiotics could prevent …
Circumferential waves in a composite circular cylinder

Abstract Circumferential waves propagating in a layered, circular cylinder are studied. The cylinder consists of an elastic circular core encased in a hollow, circular cylinder of distinctly different elastic properties. Both smooth and bonded contact are considered. The effect of curvature and layer thickness on the phase velocity of the lowest mode(s) is investigated for both an acoustically softer and an acoustically stiffer layer. When the outer radius of the composite cylinder is unbounded, Stoneley waves are a limiting case as the ratio of the radius of the core to the wavelength increases beyond bounds. When the outer radius is finite, waves in a layer and a half-space result for this limit. Some attention is also directed to the limiting case of small layer thickness to the wavelength ratio. In the limit as this ratio vanishes, the motion of the core reduces to that of Rayleigh waves on the curved surface. For smooth contact, the motion of the core becomes uncoupled from that of the layer for this limiting case, and two distinct modes are seen to exist.
DFT and G2 calculations on the NO2–H2O molecular complex

Abstract A variety of density functional and G2-level calculations suggest that NO2 interacts only weakly with H2O. Using the HF, MP2, G2, and DFT methods, the energy of stable interaction is predicted to be on the order of 0–8 kJ mol−1, depending on the method. This is not much stronger than NO–H2O complexes studied earlier. Unlike NO–H2O, however, only one stationary-point structure was found for NO2–H2O.
Mitochondrial Reactive Oxygen Species in Mice Lacking Superoxide Dismutase 2 ATTENUATION VIA ANTIOXIDANT TREATMENT

Abstract Mice that lack the mitochondrial form of superoxide dismutase (SOD2) incur severe pathologies and mitochondrial deficiencies, including major depletion of complex II, as a consequence of buildup of endogenous reactive oxygen species (Melov, S., Coskun, P., Patel, M., Tuinstra, R., Cottrell, B., Jun, A. S., Zastawny, T. H., Dizdaroglu, M., Goodman, S. I., Huang, T. T., Miziorko, H., Epstein, C. J., and Wallace, D. C. (1999) Proc. Natl. Acad. Sci. U. S. A. 96, 846–851 and Li, Y., Huang, T. T., Carlson, E. J., Melov, S., Ursell, P. C., Olson, J. L., Noble, L. J., Yoshimura, M. P., Berger, C., Chan, P. H., Wallace, D. C., and Epstein, C. J. (1995) Nat. Genet. 11, 376–381). These problems can be greatly attenuated or rescued by synthetic antioxidant treatment, such as with the catalytic antioxidant EUK189 (Hinerfeld, D., Traini, M. D., Weinberger, R. P., Cochran, B., Doctrow, S. R., Harry, J., and Melov, S. (2004) J. Neurochem. 88, 657–667). We have used heart mitochondria from sod2 null mice to better understand mitochondrial reactive oxygen species production both in the absence of SOD2 and following in vivo antioxidant treatment. Isolated heart mitochondria from 5-day-old sod2 null animals respiring on the complex II substrate succinate exhibited statistically significant higher levels of mitochondrial (157%, p < 0.01) but significantly less H2O2 (33%, p < 0.001) than wild type littermates. Treatment of sod2 nullizygous mice with EUK189 proportionately increased the levels of complex II and H2O2. Increased production of resulting from complex II normalization had no effect on steady state levels due to the rapid conversion to H2O2, a process presumably aided by the presence of the EUK189, an SOD mimetic.
Uniform Sampling of Steady-State Flux Spaces: Means to Design Experiments and to Interpret Enzymopathies

Reconstruction of genome-scale metabolic networks is now possible using multiple different data types. Constraint-based modeling is an approach to interrogate capabilities of reconstructed networks by constraining possible cellular behavior through the imposition of physicochemical laws. As a result, a steady-state flux space is defined that contains all possible functional states of the network. Uniform random sampling of the steady-state flux space allows for the unbiased appraisal of its contents. Monte Carlo sampling of the steady-state flux space of the reconstructed human red blood cell metabolic network under simulated physiologic conditions yielded the following key results: 1), probability distributions for the values of individual metabolic fluxes showed a wide variety of shapes that could not have been inferred without computation; 2), pairwise correlation coefficients were calculated between all fluxes, determining the level of independence between the measurement of any two fluxes, and identifying highly correlated reaction sets; and 3), the network-wide effects of the change in one (or a few) variables (i.e., a simulated enzymopathy or fixing a flux range based on measurements) were computed. Mathematical models provide the most compact and informative representation of a hypothesis of how a cell works. Thus, understanding model predictions clearly is vital to driving forward the iterative model-building procedure that is at the heart of systems biology. Taken together, the Monte Carlo sampling procedure provides a broadening of the constraint-based approach by allowing for the unbiased and detailed assessment of the impact of the applied physicochemical constraints on a reconstructed network.
Intramolecular photoinduced electron transfer: A dimethylaniline constrained to the face of a naphthalene through a bicyclic scaffold

Abstract The α, α′-annelation of the enamine of 1,3-dihydro-2-phenalenone with ETAC-I [2-(p-nitrophenyl)allyl trimethylammonium iodide] affords an aromatic bicyclic framework, 9-endo-p-nitrophenyl-8,9,10,11-tetrahydro-7,11-methano-12-keto-7H-cyclooocta(de)naphthalene having the p-nitrophenyl group positioned over the naphthalene ring. The X-ray structure of a derivative was obtained. The nitro function was transformed to a dimethylamino group giving a molecule well suited to evaluate intramolecular photoinduced electron transfer [PET] between the two aromatic elements. The charge transfer [CT] was determined using solvents of different polarity in the examination of the fluorescence spectra.
Structure-function analysis of the Saccharomyces cerevisiae tridecapeptide pheromone using alanine-scanned analogs

Twenty-six peptide analogs of the Saccharomyces cerevisiae alpha-factor, a tridecapeptide mating pheromone (W1H2W3L4Q5L6K7p8G9Ql0P11M12Y13) with either L- or D-alanine replacement of each amino acid residue (Ala-scanned) and with the isosteric replacement of methionine at position 12 by norleucine, were synthesized, purified to homogeneity and assayed for biological activity and receptor binding. Two new and effective antagonists, [D-Ala3,Nle12]alpha-factor and [D-Ala4,Nle12]alpha-factor, were found among the series, and the [D-Ala10,Nle12]alpha-factor demonstrated a marked ability to increase the biological activity of [Nle12]alpha-factor without having any effect by itself. One analog, the [L-Ala1 alpha-factor, showed a 3-fold increase in bioactivity over the [Nle12]alpha-factor, although its binding to the alpha-factor receptor was about 70-fold less than [Nle12]alpha-factor. Residues near the carboxyl terminus contributed more strongly to receptor binding than other residues, whereas those near the amine terminus of the alpha-factor played an important role in signal transduction. The effect of insertion of D-Ala residues at positions 7, 8, 9 and 10 on bioactivity and receptor binding of the peptide suggested a specific positioning role of the central loop in establishing optimal contacts between the receptor and the ends of the pheromone. We conclude that the alpha-factor may be divided into segments with dominant roles in forming the biologically active pheromone conformation, in receptor binding and in initiating signal transduction. The discovery of such relationships was made possible by the systematic variation of each residue in the peptide and by the testing of each analog in highly defined biological and binding assays.
Teaching theory: A response to Nelson, Henry, Holcomb, Guajardo, and Jenlink

An act of leadership is always an act of practical theory. We lead because we hold visions of the world as it ought to be, because of the not yet, because of the potential that we see in ideas and people. Yet, there still exists a perceived binary between leadership theory (in the strong sense) and leadership practice, a binary that divides organizations, classrooms, and the differing bodies of leadership literature. In this Symposium, Duncan Waite and his colleagues discuss the barriers they have faced in bringing theory to the educational leadership classroom, as well as the promise they feel theory holds for more productive, equitable, and humane schooling organizations.
Acoustooptic spectral estimation: a statistical analysis.

The power spectral density estimate obtained by an acoustooptic (AO) system is analyzed. We find that the variance of the estimate depends on the ratio T2 /T1, where T1 is the aperture of the AO cell and T2 is the integration time of the detector.
Optimization trade-offs in the design of wireless sensor and actor networks

Wireless sensor and actor networks (WSANs) are composed of static sensor nodes and mobile actor nodes. We assume actors have a random initial location in the two-dimensional sensing area. The objective is to move each actor to a location such that every sensor node is within a bounded number of hops from some actor. Because sensor nodes have limited energy, the new actor locations are chosen as to minimize the transmission range required from the sensor nodes. However, actors also have a limited (although larger) power supply, and their movement depletes their resources. It follows that by carefully choosing the new actor locations, the total actor movement can be minimized. In this paper, we study the trade-off between minimizing sensor transmission radius and minimizing actor movement. Due to the complexity of the problem, we introduce an optimal ILP formulation, and compare its results against a proposed heuristic. For the ILP solution to be feasible, we introduce a finite set of potential actor positions such that an optimal solution is guaranteed to be found within this set.