cssi/SciSciGPT-SciSciNet huggingface dataset:
Why don't tobacco hornworms (Manduca sexta) become dehydrated during larval‐pupal and pupal‐adult development

Studies of water loss during metamorphosis of insects have usually been confined to the pupal stage where both cuticular and respiratory control of transpiration have been reported. In Manduca sexta and other lepidopterans, preparation for pupation actually begins several days before pupation when the animals stop feeding and begin searching for an appropriate pupation site, a burrow for M. sexta. This study examines some aspects of water balance maintenance from the initial period of searching to the final time of eclosion. Behavior is important for reducing water loss, as animals which fail to find an appropriate pupation site continue to lose water at twice the rate of animals which are burrowed (10 vs. 5 mg H2O/g·h). Part of this is explained by exposure to light as unburrowed animals in constant dark are intermediate in water loss. The epicuticle during the pupal stage reduces water loss rate eight to tenfold, removal causing animals to lose water at 4 mg (g·h)−1. M. sexta does appear to be capable of storing water in preparation for metamorphosis, since individually raised animals consistently have water contents higher than animals reared in large groups. A drop in water loss during the larva-pupal development is correlated with increased hemolymph ecdysone titer, although how is unknown. Pupal water loss can be divided into cuticular and respiratory pathways, with cuticular loss accounting for two-thirds of 0.7 mg H2O (g·h)−1 loss rate. Finally, an increase in hemolymph osmotic pressure just prior to ecdysis may aid in reclamation of molting fluid.
Health Care Institutions, Communication, and Physicians' Experience of Managed Care A Multilevel Analysis

This study uses the institutional theory of organizational communication (ITOC) to explain physicians' reactions to managed care. ITOC posits that enduring beliefs and practices both transcend and shape particular organizations and organizing. The authors find that physicians' institutional beliefs moderated the negative relationship between managed care medical practice and satisfaction. ITOC also posits that the negotiation of institutional, environmental, organizational, and individual factors occurs through communication. Controlling for these factors, communication with managed care representatives remains significantly and positively related to satisfaction. The results provide support for ITOC and macro approaches to organizational communication research and offer insights for the management of professionals in general and physicians in particular.
Re-emplacing Place in the “Global Here and Now”—Critical Ethnographic Case Studies of Native American Language Planning and Policy

In Native American communities, the “global here and now” (Appadurai, 2001) is linked to twin movements for standardization and English supremacy, resulting in the decline of Indigenous languages and persistent educational disparities. This article takes up Appadurai's call to democratize research on globalization, juxtaposing theories that emphasize mobility, the distribution of sociolinguistic resources, and transnational connectivities with an Indigenous epistemological stance stressing continuity and place. Drawing on ethnographic data from Hopi, Navajo, and Yup'ik cases, the article then inspects the processes by which these language practices are being re-emplaced in new concrete and mobile spaces by Indigenous practitioner-intellectuals. The article concludes by problematizing the tensions between globalizing/standardizing discourses and Indigenous senses of place, returning to Appadurai's call for collaborative research on globalization that contributes to new, liberatory language pedagogies.
Olfactory bulb interconnections in soft shell turtle

Unilateral injections of horseradish peroxidase and radioactive amino acids in the olfactory bulbs of soft shell turtles revealed unique pathways for interbulbar communication. The two olfactory bulbs exchange dendrites and axons directly through their fused external plexiform and internal plexiform laminae.
Comparison of Cascade, Baseline, and Lattice Architectures for Ultra-Compact RF Photonic Filters on SOI

We compare the cascade, baseline, and lattice architectures for a four-pole, four-zero photonic filter implemented using high-Q resonator-based components on SOI. These filters are fully reconfigurable and very compact (total area 0.15 mm2).
Structure and dynamics of the antitumor drugs nogalamycin and disnogalamycin complexed to d(CGTACG)2: comparison of crystal and solution structures.

Abstract The nuclear magnetic resonance (NMR) solution structures of the 2:1 complexes of nogalamycin-d(CGTACG) 2 (Ng-CGTACG) and disnogalamycin-d(CGTACG) 2 (DNg-CGTACG) have been determined by a quantitative treatment of two-dimensional nuclear Overhauser effect (2D-NOE) crosspeak intensities. The 1.3 A resolution crystal structure of the 2:1 complex of Ng-CGTACG was used as a starting model for refinement using the procedure, SPEDREF [Robinson and Wang, Biochemistry 31 (1992) 3524–3533], which incorporates full matrix relaxation theory and simulated annealing minimization. The refined solution structures have R-factors of 16.1 and 19.6% between the observed and simulated NOEs for Ng-CGTACG and DNg-CGTACG, respectively. The refined NMR structures retain major features of the crystal structure in which the elongated aglycone chromophore is intercalated between the CpG steps with its nogalose and aminoglucose lying in the minor and major grooves, respectively. The root mean square deviation between the solution and crystal structure for the complexes is 1.01 A (Ng-CGTACG) and 1.20 A (DNg-CGTACG) for the drug, plus the three base pairs surrounding the drug, indicating a very similar local structure at the intercalation site. In the NMR structure, the two G:C Watson-Crick base pairs (C 1 :G 12 and G 2 :C 11 ) that wrap around the aglycone have large buckles, as do those seen in the crystal structure. There is a 22° bend at the T 3 -A 4 step in the refined solution structure. This rearrangement of the solution conformation is likely due to the absence of crystal packing. Specific hydrogen bonds between the drug and G:C bases in both grooves of the helix are preserved in the solution structure. A separate study of the 2:1 complex at low pH showed that the terminal G-C base pairing is destabilized.
Adolescents’ Commitment to Continuing Psychotropic Medication: A Preliminary Investigation of Considerations, Contradictions, and Correlates

This mixed-method study examines (1) the extent to which fifty adolescents receiving wraparound treatment and prescribed psychotropic medication for various psychiatric disorders report that they would continue taking medication if the decision was entirely their own (termed "medication commitment"); (2) their general subjective experiences with medication; and (3) which medication experiences and clinical, social, and demographic factors are associated with greater medication commitment. We found that most adolescents (62%) would discontinue treatment; these "less committed" youth were more likely to report various negative medication perceptions and experiences in open-ended questions, relative to "committed" youth. Multivariate analysis indicated that significant correlates of commitment to medication were: taking antipsychotic medication, greater perceived family support, and lack of perceived coercion to take the medication; clinical or demographic factors were not significantly related to medication commitment. The results reinforce the importance of addressing youths' concerns about medication and maximizing their participation in treatment decision-making.
Grapefruit juice inhibits CYP2A6 and nicotine metabolism

Background/Aims Grapefruit juice is a strong inhibitor of CYP3A4 leading to clinically important interactions. The aim was to study the effect of grapefruit juice on the metabolism of nicotine, primarily a CYP2A6 substrate. Methods 10 volunteers were given 2 mg oral dose of deuterium-labeled nicotine on three occasions together with 1 L of water, grapefruit juice or half-strength grapefruit juice in randomized order. Nicotine and metabolites were analyzed in plasma and urine for 8 hours. Results Grapefruit juice inhibited the formation of cotinine from nicotine (AUCCOT 0–8hr 6807 vs. 7805 vs. 8007 min*ng/ml, grapefruit juice, diluted grapefruit juice, and water, respectively, p< 0.05). Tmax of cotinine was delayed, and Cmax lower with grapefruit juice than with water (Tmax 216 vs. 159 vs. 147 min, p< 0.05, Cmax 18 vs. 21 vs. 22 ng/ml, p< 0.05). Grapefruit juice increased renal clearance of nicotine compared to water (231 vs. 123 ml/min, p< 0.05). Other pharmacokinetic parameters of nicotine were not affected. Conclusions Grapefruit juice inhibits the metabolism of nicotine to cotinine, a pathway mediated by CYP2A6. The inhibition is modest, and the effect on total nicotine clearance was offset by the increase in the renal clearance of nicotine. However, the inhibition of CYP2A6 by grapefruit juice may be of clinical significance with other drugs metabolized by CYP2A6. Clinical Pharmacology & Therapeutics (2005) 77, P75–P75; doi: 10.1016/j.clpt.2004.12.178
Loss of cholinergic phenotype in basal forebrain coincides with cognitive decline in a mouse model of Down's syndrome.

Mice with segmental trisomy of chromosome 16 (Ts65Dn) have been used as a model for Down's syndrome. These mice are born with a normal density of basal forebrain cholinergic neurons but, like patients with Down's syndrome, undergo a significant deterioration of these neurons later in life. The time course for this degeneration of cholinergic neurons has not been studied, nor is it known if it correlates with the progressive memory and learning deficits described. Ts65Dn mice that were 4, 6, 8, and 10 months old were sacrificed for evaluation of basal forebrain morphology. Separate groups of mice were tested on visual or spatial discrimination learning and reversal. We found no alterations in cholinergic markers in 4-month-old Ts65Dn mice, but thereafter a progressive decline in density of cholinergic neurons, as well as significant shrinkage of cell body size, was seen. A parallel loss of staining for the high-affinity nerve growth factor receptor, trkA, was observed at all time points, suggesting a biological mechanism for the cell loss involving this growth factor. Other than transient difficulty in learning the task requirements, there was no impairment of trisomic mice on visual discrimination learning and reversal, whereas spatial learning and reversal showed significant deficits, particularly in the mice over 6 months of age. Thus, the loss of ChAT-immunoreactive neurons in the basal forebrain was coupled with simultaneous deficits in behavioral flexibility on a spatial task occurring for the first time around 6 months of age. These findings suggest that the loss of cholinergic function and the simultaneous decrease in trkA immunoreactivity in basal forebrain may directly correlate with cognitive impairment in the Ts65Dn mouse
Doveweed (Murdannia nudiflora) germination and emergence as affected by temperature and seed burial depth

Abstract Doveweed is becoming more common in agronomic crops in North Carolina. Laboratory and greenhouse experiments were conducted to determine the effect of temperature and seed burial depth on doveweed germination and emergence. Germination of lightly scarified seed at constant temperature was well described by a Gaussian model, which estimated peak germination at 28 C. Similar maximum percentage of germination was observed for optimal treatments under both constant and alternating temperatures. Among alternating temperatures, a 35/25 C regime gave greatest germination (77%). In spite of similar average daily temperatures, germination was greater with alternating temperature regimes of 40/30 and 40/35 C (65 and 30%, respectively) than constant temperatures of 36 and 38 C (4 and 0%, respectively). No germination was observed at 38 C constant temperature or for alternating temperature regimes of 20/10 and 25/15 C. Light did not enhance germination. Greatest emergence occurred from 0 to 1 cm, with a redu...
Antibodies against immunodominant antigens of Mycobacterium tuberculosis in subjects with suspected tuberculosis in the United States compared by HIV status

The immunodominance of Mycobacterium tuberculosis proteins malate synthase (MS) and MPT51 has been demonstrated in case-control studies with patients from countries in which tuberculosis (TB) is endemic. The value of these antigens for the serodiagnosis of TB now is evaluated in a cross-sectional study of pulmonary TB suspects in the United States diagnosed to have TB, HIV-associated TB, or other respiratory diseases (ORD). Serum antibody reactivity to recombinant purified MS and MPT51 was determined by enzyme-linked immunosorbent assays (ELISAs) of samples from TB suspects and wellcharacterized control groups. TB suspects were diagnosed with TB (n 87; 49% sputum microscopy negative, 20% HIV )o r ORD (n 63; 58% HIV). Antibody reactivity to MS and MPT51 was significantly higher in U.S. HIV/TB samples than in HIV/TB samples (P < 0.001), and it was significantly higher in both TB groups than in control groups with latent TB infection (P < 0.001). Antibody reactivity to both antigens was higher in U.S. HIV/TB samples than in HIV/ORD samples (P 0.052 for MS, P 0.001 for MPT51) but not significantly different between HIV/TB and HIV/ORD. Among U.S. HIV TB suspects, a positive anti-MPT51 antibody response was strongly and significantly associated with TB (odds ratio, 11.0; 95% confidence interval, 2.3 to 51.2; P 0.002). These findings have implications for the adjunctive use of TB serodiagnosis with these antigens in HIV subjects. The detection and treatment of individuals who are at early stages of active pulmonary tuberculosis (TB) is critical for the successful control and elimination of TB (34, 38). Mycobacterium tuberculosis is a slow-growing pathogen, and it takes months to years for an infection (and, presumably, reactivation) to progress to clinical TB. In resource-limited countries, the microscopic examination of smears made directly from unprocessed sputum are used for diagnosis, resulting in the identification of only advanced TB patients with high bacillary burden. In contrast, in industrialized settings the combined use of the fluorescence microscopy of decontaminated and concentrated sputum, mycobacterial culture, and nucleic acid amplification technologies permits the identification of patients with much lower bacillary burden and, thus, in the early stages of TB. Still, only around 50% of TB cases are rapidly diagnosed by optimized microscopy (5, 18). While adjunctive amplification methods increase the yield of confirmed TB, albeit with added cost and delays, around 20% of TB cases remain without microbiologic confirmation (5, 18). Additional tests that can enhance the rapid identification of patients at early stages of TB are required to add to the armamentarium of TB diagnostic tests. The amplification power of immune responses potentially can detect TB at a low antigen threshold and without requiring a specimen from the site of infection. Assays that detect TB infection by measuring the gamma interferon release of circulat
Eimeria acervulina Infection in Chicks Fed Cobalt in the Presence or Absence of Excess Dietary Methionine

An experiment was conducted with young, male, crossbred chicks to investigate the interaction between dietary cobalt, methionine and experimental Eimeria acervulina infection (duodenal coccidiosis). Coccidiosis and dietary cobalt (250 mg/kg) depressed weight gain and efficiency of feed utilization; cobalt toxicity, however, was exacerbated by the coccidial infection, resulting in a depression in performance greater than could be accounted for by the independent additive effect of each entity. Dietary cobalt increased the cobalt concentration of the liver, kidney and gallbladder (with bile); experimental coccidiosis in the absence of excess dietary methionine resulted in a twofold increase in cobalt deposition in the liver and gallbladder. Excess supplemental methionine partially alleviated the decrease in chick performance and the increase in tissue cobalt content caused by dietary cobalt in both healthy and infected chicks, but with a slightly greater efficacy in the coccidiosis-infected chicks.
The asymptotic order of the random k-SAT threshold

Form a random k-SAT formula on n variables by selecting uniformly and independently m=rn clauses out of all 2/sup k/ (/sub k//sup n/) possible k-clauses. The satisfiability threshold conjecture asserts that for each k there exists a constant r/sub k/ such that, as n tends to infinity, the probability that the formula is satisfiable tends to 1 if r r/sub k/. It has long been known that 2/sup k//k 2/sup k-1/ ln 2-d/sub k/, where d/sub k//spl rarr/(1+ln2)/2. Our proof also allows a blurry glimpse of the "geometry" of the set of satisfying truth assignments.
Influence of different levels of dietary pyridoxine on milk composition in the rat.

The effects of five different levels of dietary pyridoxine on milk composition were studied in the rat. Sprague-Dawley strain rats received diets containing 1.2, 2.4, 4.8, 9.6 or 19.2 mg pyridoxine-HCl/kg diet throughout growth, gestation and lactation. Milk samples obtained on days 10, 11, and 12 of lactation were similar in concentrations of total fat, solids-not-fat, carbohydrate, casein and non-casein protein for rats fed the five levels of pyridoxine. The level of vitamin B-6 in milk was significantly higher for rats fed 9.6 or 19.2 mg pyridoxine.HCl/kg diet compared to values for rats fed the three lower levels of vitamin. A higher level of dietary pyridoxine (9.6 mg/kg diet) was required to increase the levels of the vitamin in mammary gland and milk than was needed for maternal liver (4.8 mg/kg) or muscle tissue (2.4 mg/kg). The findings indicated that as the level of pyridoxine was decreased in the diet from an apparently adequate level, the concentration of the vitamin in milk decreased before that in liver or muscle tissue. This suggested that the concentration of the vitamin in milk was an indicator of marginal deficiency of vitamin B-6.
Morphological changes and photosynthate allocation in ageing Hebeloma crustuliniforme (Bull.) Quel. and Laccaria bicolor (Maire) Orton mycorrhizas of Pinus ponderosa Dougl. ex. Laws

S L' M M .\ R YSeedlings of Pinus ponderosa Dougl. ex. Laws were grown in root observation containers. They were inoculatedwith either Hebeloma cms tut ini forme (Bull.) Quel. or Laccaria bicolor (Maire) Orton or left uninoculated (control).On a monthly basis starting at the eighth montb of a 12-month growing period, roots (mycorrhizal root tips frominoculated plants, non-mycorrhizal from control plants) were traced onto acetate sheets. Eacb root tip wasclassified as 'light', 'intermediate' or 'dark' in colour. Roots initiated between months eight and nine weremonitored for the next ^0 d. AU root tips progressed from light-brown to dark-brown to black for all threetreatments. Hebeloma crustulimforme, and to a lesser extent L. bicolor, retarded this progression relative to thecontrol. At the end of 12 months, seedlings were labelled with '^CO.^ to determine the effects of ectomycorrhizalinoculation on carbon supply to roots of the different morphological categories. Tbe amount of '''C in 'light'L. bicolnr and H. crustuliniforme mycorrhizas was 2-3 and 1 8 times greater, respectiv ely, than tbat in ' light' contro lroot tips. The amount of ^^C in mycorrhizas of the inoculated treatments and, to a lesser extent, roots of the controlseedlings decreased as they progressed from 'light' to 'dark'. It is concluded that ponderosa pine seedlingscontinue to allocate photosynthate to morphologically older roots, perhaps to meet maintenance requirements orto supply carbon for growth and metabolism of extra-matvical hyphae. Such allocation may enhance rootlongevity, whieh would bave an important influence on tree, forest and soil carbon budgets.Key words: Ectomycorrhizas, Hebeloma crustuliniforme, Laccaria bicolor, root ageing, '""C translocation.order of se\'eral months to a year (Harlev & SmithINTRODl CTION ,„„. ^ ., j e V^ • 1n'n•>^ o
Co-pyrolysis of low rank coals and biomass: Product distributions

Pyrolysis and gasification of combined low rank coal and biomass feeds are the subject of much study in an effort to mitigate the production of green house gases from integrated gasification combined cycle (IGCC) systems. While co-feeding has the potential to reduce the net carbon footprint of commercial gasification operations, success of this strategy requires investigation of the effects of coal/biomass co-feeding on reaction kinetics and product distributions. Southern yellow pine was pyrolyzed in a semi-batch type drop tube reactor with either Powder River Basin sub-bituminous coal or Mississippi lignite at several temperatures and feed ratios. Product gas composition of expected primary constituents (CO, CO2, CH4, H2, H2O, and C2H4) was determined by in situ mass spectrometry while minor gaseous constituents were determined using a GC–MS. Product distributions are fit to linear functions of temperature, and quadratic functions of biomass fraction, for use in computational co-pyrolysis simulations. The results are shown to yield significant nonlinearities, particularly at higher temperatures and for lower ranked coals. The co-pyrolysis product distributions evolve more tar, and less char, CH4, and C2H4, than an additive pyrolysis process would suggest. For lignite co-pyrolysis, CO and H2 production are also reduced. The data suggests that rapid pyrolysis of biomass produces hydrogen that stabilizes large radical structures generated during the early stages of coal pyrolysis. Stabilization causes these structures to be released as tar, rather than crosslinking with one another to produce secondary char and light gases. Finally, it is shown that, for the two coal types tested, co-pyrolysis synergies are more significant as coal rank decreases, likely because the initial structure in these coals contains larger pores and smaller clusters of aromatic structures which are more readily retained as tar in rapid co-pyrolysis.
Polar localization of Escherichia coli chemoreceptors requires an intact Tol–Pal complex

Summary Subcellular biomolecular localization is critical for the metabolic and structural properties of the cell. The functional implications of the spatiotemporal distribution of protein complexes during the bacterial cell cycle have long been acknowledged; however, the molecular mechanisms for generating and maintaining their dynamic localization in bacteria are not completely understood. Here we demonstrate that the trans-envelope Tol–Pal complex, a widely conserved component of the cell envelope of Gram-negative bacteria, is required to maintain the polar positioning of chemoreceptor clusters in Escherichia coli. Localization of the chemoreceptors was independent of phospholipid composition of the membrane and the curvature of the cell wall. Instead, our data indicate that chemoreceptors interact with components of the Tol–Pal complex and that this interaction is required to polarly localize chemoreceptor clusters. We found that disruption of the Tol–Pal complex perturbs the polar localization of chemoreceptors, alters cell motility, and affects chemotaxis. We propose that the E. coli Tol–Pal complex restricts mobility of the chemoreceptor clusters at the cell poles and may be involved in regulatory mechanisms that co-ordinate cell division and segregation of the chemosensory machinery.
Maximum likelihood estimation in the proportional hazards cure model

The proportional hazards cure model generalizes Cox’s proportional hazards model which allows that a proportion of study subjects may never experience the event of interest. Here nonparametric maximum likelihood approach is proposed to estimating the cumulative hazard and the regression parameters. The asymptotic properties of the resulting estimators are established using the modern empirical process theory. And the estimators for the regression parameters are shown to be semiparametric efficient.
Linewidth and photon statistics of a single atom laser

Summary form only given. The basic model considered in this paper is a single atom inside an optical cavity. We consider both three- and four-level atomic systems and use incoherent pumping for both. We present numerical results of the laser linewidth and the second-order intensity correlation function. These results are obtained with use of the quantum trajectory method, using the formalism of Carmichael.
One-pass vector quantizer design by sequential pruning of the training data

A one-pass vector quantizer design algorithm is presented. The algorithm sequentially selects a subset of the training vectors (in a high density area of the training data space) and computes a VQ code vector. Next, a sphere is constructed about the code vector whose radius is determined such that the encoding error for points within the sphere is acceptable. Finally, the data within the sphere is then pruned (deleted) from the training data set. This procedure continues on the remainder of the training set until the desired number of code vectors are located. This one-pass VQ design algorithm is compared with several benchmark results for uncorrelated Gaussian, correlated Gaussian, and Laplace sources; its performance is seen to be as good or better than the benchmark results. Further, the one-pass algorithm needs only slightly more computation than a single iteration of the LBG algorithm.
Toward service systems engineering

A case is made herein for further developing a branch of systems engineering that focuses on problems and issues, which arise in the service sector. We argue for this special focus not only because of the size and importance of the service sector but also because of the unique opportunities that systems engineering can exploit in the production and delivery of services. We begin by considering the economic, technological and demographic contexts within which the service sector has flourished; we then address both services, especially emerging services, and systems engineering, followed by a discussion of how to advance the field of service systems engineering, and concluding with several remarks. In particular, a number of service systems engineering methods are identified to enhance the production and delivery of services, especially taking advantage of the unique features that characterize services - namely, services, especially emerging services, are information-driven, customer-centric, e-oriented, and productivity-focused.
Kin Networks, Marriage, and Social Mobility in Late Imperial China

To assess claims about the role of the extended family in late imperial Chinese society, we examine the influence of kin network characteristics on marriage, reproduction, and attainment in Liaoning Province in Northeast China in the eighteenth and nineteenth centuries. We compare the influences on outcomes of the number and status of different types of kin as well as the seniority of the individual within each type of kin group. We find that the characteristics of kin outside the household did matter for individual outcomes but that patterns of effects were nuanced. While based on our results we concur that kin networks were important units of social and economic organization in late imperial China, we conclude that their role was complex.
Effect of Extraction Procedures on Fluorescent Chromophores in Milk

The oxidation of membrane lipids of freeze-dried Milk Fat Globule Membranes (MFGM) was studied using a fluorescence technique involving two different extraction procedures to obtain lipophilic fluorescent chromophores. MFGM underwent extensive lipid oxidation when stored under air, at controlled temperature and humidity and fluorescent compounds were formed with excitation maxima at 350 nm and emission maxima at 440 nm. Direct extraction of fluorescent compounds with an organic solvent mixture (Cl3CH:CH3OH 2:1 v/v) gave reproducible results reflecting well the progress of oxidation. Solvent extraction after previous reconstitution (to original water content) of the dry samples was less satisfactory.
Identifying thyroid stem/progenitor cells: advances and limitations

Continuing advances in stem cell science have prompted researchers to envisage the potential application of stem cells for the management of several debilitating disorders, thus raising the expectations of transplant clinicians. In particular, in order to find a source of adult stem cells alternative to embryonic stem cells (ESCs) for the exploration of novel strategies in regenerative medicine, researchers have attempted to identify and characterise adult stem/progenitor cells resident in compact organs, since these populations appear to be responsible for physiological tissue renewal and regeneration after injury. In particular, recent studies have also reported evidence for the existence of adult stem/progenitor cell populations in both mouse and human thyroids. Here, I provide a review of published findings about ESC lines capable of generating thyroid follicular cells, thyroid somatic stem cells and cancer stem cells within the thyroid. The three subjects are analysed by also considering the criticism recently raised against their existence and potential utility. I comment specifically on the significance of resident thyroid stem cells in the developmental biology of the gland and their putative role in the pathogenesis of thyroid disorders and on the protocols employed for their identification. I finally provide my opinion on whether from basic science results obtained to date it is possible to extrapolate any convincing basic for future treatment of thyroid disorders.
Neural mechanisms of saccade target selection: gated accumulator model of the visual-motor cascade.

We review a new computational model developed to understand how evidence about stimulus salience in visual search is translated into a saccade command. The model uses the activity of visually responsive neurons in the frontal eye field as evidence for stimulus salience that is accumulated in a network of stochastic accumulators to produce accurate and timely saccades. We discovered that only when the input to the accumulation process was gated could the model account for the variability in search performance and predict the dynamics of movement neuron discharge rates. This union of cognitive modeling and neurophysiology indicates how the visual–motor transformation can occur, and provides a concrete mapping between neuron function and specific cognitive processes.
Sustained attention development during the toddlerhood to preschool period: associations with toddlers' emotion regulation strategies and maternal behaviour

The current study examined the role of maternal behavior and toddlers' emotion regulation strategies in the development of children's sustained attention abilities. Participants for this study included 447 children (232 girls) obtained from three different cohorts participating in a larger ongoing longitudinal study. When the children were 2 years of age, mothers brought their children to the laboratory and were videotaped during several tasks designed to elicit emotion regulation and mother- child interaction. Sustained attention was also measured at the same visit via a laboratory task and in a subsequent visit when children were 4.5 years of age. Results indicated that toddlers' use of help-seeking emotion regulation strategies was positively related to sustained attention while avoidance behaviors and maternal behavior characterized by high levels of overcontrolling/intrusiveness were negatively related to sustained attention at age 2. Significant interactions emerged such that high levels of maternal warmth/responsiveness buffered the negative associations between low use of distraction and high use of self-comforting emotion regulation strategies and sustained attention at age 2. Maternal behavior characterized by high levels of warmth/responsiveness also predicted greater growth in sustained attention from age 2 to 4.5. These findings are discussed in terms of how maternal behaviors and children's use of active versus passive emotion regulation strategies relate to sustained attention abilities.
Privilege and Creative Destruction: The Charles River Bridge Case

In this now-classic work in legal and constitutional theory, Stanley Kutler examines one of the Supreme Court's most celebrated decisions: the right of the state of Massachusetts to erect a free bridge over the Charles River in 1837--even though the state had previously chartered a privately owned toll bridge at the same location. (Legal Reference)
Spatial organization of Pseudomonas aeruginosa biofilms probed by combined matrix-assisted laser desorption ionization mass spectrometry and confocal Raman microscopy.

Bacteria growing as surface attached biofilms differ significantly from planktonic cells in several important traits that are reflected in the spatiotemporal organization of the cells and the extracellular polymeric substances they secrete. The structural and chemical features that define these biofilms are explored here using a combination of matrix-assisted laser desorption ionization mass spectrometry (MALDI MS) and confocal Raman microspectroscopies (CRM) to characterize and compare the composition and distribution of biomolecules found in biofilms and planktonic cells of the bacterium Pseudomonas aeruginosa. Three-day old P. aeruginosa biofilms show dramatic differences in molecular composition compared to planktonic cultures. CRM reveals that wild-type planktonic cell Raman spectra are characterized by bands linked to cellular constituents and are dominated by contributions from DNA- and RNA-related bands. In contrast, biofilm spectra are dominated by bands characteristic of glycolipids – rhamnolipids – polysaccharides and by secreted proteins. LDI MS was applied in turn to identify the rhamnolipids present in the biofilm. Experiments were also conducted using an acyl homoserine lactone quorum sensing-deficient mutant (ΔlasIΔrhlI), which is incapable of producing rhamnolipids. CRM and LDI MS analyses revealed that while molecular composition of the planktonic quorum sensing-deficient cells is similar to that of the wild-type planktonic cells, several compositional differences are observed in the mutant after biofilm growth, including complete absence of detectable rhamnolipids. CRM vibrational spectra of the mutant cells are very similar for planktonic and biofilm growth conditions, indicating that biofilm formation is greatly hindered in the absence of functioning quorum sensing machinery.
Behavioral synthesis via engineering change

Engineering change (EC) is a technique that enables a designer to rapidly perform minor specification alternations while minimally resynthesizing only small portions of the specification throughout several levels of design abstraction. In this paper, we introduce the first EC-based synthesis technique for coordinated design optimization in multiple steps. The technique has four phases: optimization region identification, feedback formulation, resynthesis in first step, and finally resynthesis in the second design step. To demonstrate the technique, we focus on behavioral synthesis and transformation, scheduling, and register assignment steps. We developed a generic EC-based approach for design optimization during multiple consecutive synthesis steps. Next, we show how one can use EC to enhance coordinated application of transformations and scheduling, and scheduling and register assignment.
Editorial comment: Recurrent episodes of weak spells in a 15 year old boy.

(1) This patient was referred to a neurologist by the cardiologist with the request that he evaluate and recommend therapy for the episodes of weakness only to be told that this was not periodic paralysis (PP), as the K level was not altered during the spells. The serum potassium level in patients with PP is not useful in the diagnosis. If it is high or low, it does not secure the diagnosis of hyperkalemic or hypokalemic PP and if it is normal it does not rule out the diagnosis of either type of PP. Perhaps if the serum K level could be monitored from just before an attack through the attack one would see a relative change (either up or down
Impact Evaluation Methods in Public Economics A Brief Introduction to Randomized Evaluations and Comparison with Other Methods

Recent years have seen a large expansion in the use of rigorous impact evaluation techniques. Increasingly, public administrations are collaborating with academic economists and other quantitative ...
Approaches to Cloning of Pain-Related Ion Channel Genes

Molecular pain research is a relatively new and rapidly expanding field that represents advancement in conventional pain research. One of the fundamentals of molecular pain involves the cloning of genes and especially the ion channels specifically involved in nociceptive processing at the periphery and centrally. A variety of approaches were used to isolate these critically important genes. Cloning of these genes involved innovative strategies based on existing molecular approaches. This review will discuss well-utilized cloning approaches and their exploitation in molecular pain research.
A Phenomenological Inquiry of Clients' Experiences of Receiving a Humanistically Oriented Therapeutic Letter From Their Counselor Between Counseling Sessions

This qualitative study investigated the lived experiences of 6 female clients who received a humanistically oriented letter from their counselor between counseling appointments. Five core themes resulted concerning shared perspectives of the letter's impact on the recipients. A brief discussion, including limitations and recommendations, is provided.
DNA supercoiling, a critical signal regulating the basal expression of the lac operon in Escherichia coli

Escherichia coli lac repressor (LacI) is a paradigmatic transcriptional factor that controls the expression of lacZYA in the lac operon. This tetrameric protein specifically binds to the O1, O2 and O3 operators of the lac operon and forms a DNA loop to repress transcription from the adjacent lac promoter. In this article, we demonstrate that upon binding to the O1 and O2 operators at their native positions LacI constrains three (-) supercoils within the 401-bp DNA loop of the lac promoter and forms a topological barrier. The stability of LacI-mediated DNA topological barriers is directly proportional to its DNA binding affinity. However, we find that DNA supercoiling modulates the basal expression from the lac operon in E. coli. Our results are consistent with the hypothesis that LacI functions as a topological barrier to constrain free, unconstrained (-) supercoils within the 401-bp DNA loop of the lac promoter. These constrained (-) supercoils enhance LacI's DNA-binding affinity and thereby the repression of the promoter. Thus, LacI binding is superhelically modulated to control the expression of lacZYA in the lac operon under varying growth conditions.
Phialophora mutabilis Endocarditis

This is the first reported case of fungal endocarditis due to vegetative growth of Philalophora mutabilis on a prosthetic mitral valve. The patient had rheumatic heart disease with mitral and aortic stenosis. Four months after the mitral and aortic valves had been replaced by prostheses the patient developed congestive failure. Because of increased left atrial pressure, the mitral prosthesis was replaced. A large matted obstructive fungal vegetation was found on the prosthesis. Culture of this vegetation grew Phialophora mutabilis . The patient died postoperatively, and at autopsy the fungus was not found in other tissues. Culturally and morphologically, P. mutabilis shows wide variation in pigmentation, colonial and microscopic appearance. Conidia formation from intercalary cells along the hyphae is somewhat similar to that of Aureobasidium spp. P. mutabilis was injected into mice. Mice pretreated with cortisone died 3 to 5 weeks after intraperitoneal inoculation, while the majority of untreated mice died within 20 weeks of inoculation.
A comparison of marrow transplantation with chemotherapy for adults with acute leukemia of poor prognosis in first complete remission.

From July 1980 to November 1985, 109 patients with acute myelogenous and lymphoblastic leukemia who had reached a complete remission (CR) following induction treatment were assigned to a study comparing marrow transplantation with chemotherapy as a postremission treatment. Sixty-nine patients did not have a human leukocyte antigen (HLA)-identical donor, and therefore served as chemotherapy controls; 40 patients had HLA-identical donors, and therefore were assigned to the transplant arm. Of these, 23 were transplanted in first remission and 17 were not. Ten of these 17 were subsequently transplanted in relapse. Initially, only patients with poor prognosis determined by a predictive model were entered into the study. Subsequently, patients with moderately poor prognosis were admitted. Comparing the chemotherapy group with the patients transplanted in first CR, significant control of leukemia relapse in transplanted patients was seen in the subgroup with acute myelogenous leukemia (AML) (P less than .1), and...
Contractual Penalties in the King's Court

Clauses that provided fixed monetary penalties first appeared in English contracts and conveyances in the first decade of the thirteenth century. Rather quickly thereafter penalty clauses came to be used in a wide variety of contracts and conveyances. They were used in (1) agreements over tithes, (2) settlement of disputes, (3) arbitration agreements, (4) agreements to transfer or not to transfer land, (5) marriage property agreements, (6) warranties of title to land, (7) leases, (8) agreements to pay rents and annuities, loans, and in a variety of other transactions. The penalty clause was just another clause in the agreement. At about the middle of the thirteenth century other methods of inserting a penalty clause into an agreement began to be used. A penalty clause could be made part of a recognizance on the plea rolls, the Exchequer rolls, or the Chancery rolls. The recognizance itself could be a penalty to enforce a side agreement. A money bond could serve as a penalty rendered void if the terms of a separate, conditional acquittance were met. A bond or a statute merchant could be given to a third party under an agreement to give the bond or statute merchant to the promisee if the promisor failed to carry out his agreement. By 1348 the penal bond with conditional defeasance endorsed on the back of the bond had been invented.
Student Enrollment in World Languages: L'Égalité des Chances?

Students enrolled in world language classes experience many positive academic and developmental outcomes, and world language classes are often gateways to institutions of higher education in the United States. However, not all learners have access to world language classes. Differences in language class availability exist not only between school districts but also within individual districts. The purpose of this study was to explore world language offerings and middle and high school enrollment patterns across different school contexts in four large local education agencies in North Carolina during the 2013–2014 academic year. Findings indicated that more choices and levels of languages were offered in schools where 50% or more of the students were white. In addition, results from chi-square tests revealed that African American and Latino male students were consistently underrepresented in world language classes. Implications for students and policy makers are discussed.
Public Intellectuals and the Public Interest: Toward a Politics of Political Science as a Calling

Upon my first reading of the Etzioni autobiography, I recalled my favorite book review, written by a nine-year-old, who also should have won a prize for the youngest author and the shortest review ever: “This book told me more about penguins than I wanted to know.”
A Moving Target: Democracy

Achieving consensus on a definition of “democracy” has proven elusive. Institutions that have been taken to be essential to democracy have changed radically since the word “democrat” began to be widely used toward the end of the eighteenth century. Democratic ideas and democratic practice engender conflict that transforms institutions rather than just reproduces them. Its transformative character rests on a half-dozen key attributes of democracy: it is an actor’s concept, as well as an analyst’s; it can arouse strong feelings; it combines not always compatible ideas; it empowers dissent; it involves a dynamic mixture of inclusion and exclusion; and the democratic histories of national states have been intertwined with global domination. Two processes combine to generate much social dynamism. First, democracy’s stirring inclusionary claims have been contradicted by a complex structure of exclusions, including distinctions in rights of full participation among citizens, distinctions in rights between citizens and non-citizens, and distinctions in resources among legally equal citizens. And second, democratic practice has been fertile soil for the development of social movements. Taken together, democracy is an invitation for movements to try to shift the boundaries of inclusion and exclusion, and in so doing to expand or constrict democracy itself.
Exploration of Comprehensive Quality Evaluation Method of Cultivated Land for County Areas

The study of quality evaluation of cultivated land provided theoretical and rational support to the protection and scientific utilization of cultivated land.This paper evaluated the grain ability of cultivated land,the benefit ability of the plantation industry and the potential benefit ability of using the land as construction land,and constructed the comprehensive evaluation system of cultivated land.The system was composed of cultivated land grading,the reality level and the potential level.Basing on explaining the meaning of quality evaluation of cultivated land,this paper chose eight first level index,thirty six second level index and twenty third level index as arable land quality evaluation index.AHP were used to calculate and evaluate the quality of cultivated land,and the integrated sequence values of the evaluated unit were got.
Thin liquid/gas diffusion layers for high-efficiency hydrogen production from water splitting

Abstract In this study, a novel titanium thin LGDL with well-tunable pore morphologies was developed by employing nano-manufacturing and was applied in a standard PEMEC. The LGDL tests show significant performance improvements. The operating voltages required at a current density of 2.0 A/cm2 were as low as 1.69 V, and its efficiency reached a report high of up to 88%. The new thin and flat LGDL with well-tunable straight pores has been demonstrated to remarkably reduce the ohmic, interfacial and transport losses. In addition, well-tunable features, including pore size, pore shape, pore distribution, and thus porosity and permeability, will be very valuable for developing PEMEC models and for validation of its simulations with optimal and repeatable performance. The LGDL thickness reduction from greater than 350 μm of conventional LGDLs to 25 μm will greatly decrease the weight and volume of PEMEC stacks, and represents a new direction for future developments of low-cost PEMECs with high performance.