cssi/SciSciGPT-SciSciNet huggingface dataset:
(aSiGe/ncSi) Superlattice thin film silicon solar cell

Nanocrystalline silicon solar cell has come up as a potential material in the photovoltaic industry [1-3]. There are various benefits of nanocrystalline silicon which makes it superior to its counterparts such as amorphous silicon and amorphous silicon germanium. Narrow band gap of 1.12eV helps to generate more current by utilizing the red and infrared region of the solar spectrum. High current producing ability makes it suitable material for the bottom cell of a tandem solar cell [4]. The growth of nanocrystalline silicon is not as simple as the growth of amorphous silicon. The material grows in a conical fashion which results to large grain boundary formation if not controlled properly. The large grain boundaries hamper the electronic properties of the material. To prevent the formation of the large grain boundaries several design of nanocrystalline silicon solar cell has been used. Hydrogen profile, Power profile and Superlattice structures help to control the crystallinity of the material as it grows. There are other deposition parameters such as deposition temperature, pressure and frequency if changed may alter the morphology of the material by changing the grain size of crystals [5-10]. For high mobility and more absorption of photons we need large grains sizes of which can be achieved by high temperature and high pressure deposition conditions. We are going to discuss about the superlattice structure and ways to improve the quality of the solar cell. Amorphous silicon germanium has superior absorption coefficient as compared to amorphous silicon therefore in this report we would discuss how we can incorporate amorphous silicon germanium with nanocrystalline silicon to enhance the current of the solar cell. The grain structure and superior electronic property of nanocrystalline silicon will be utilized to collect the carriers from the thin amorphous silicon germanium tissue. We will also show the increase in current can be achieved by incorporating a back-reflector in a solar cell.
User-Perceived Requirements of Mobile Technology: Results from a Survey of Mobile Business Users

In this paper, we explore (a) the requirements of business users of mobile devices in relation with user tasks and user mobility, and (b) the relationship of the extent to which user-indicated technology requirements are met by user-perceived technology performance (fit), and overall user evaluation of the technology. Based on a survey of 216 business users of mobile technology, we found statistical evidence for a positive association of task difficulty with various functional and non-functional requirements, as well as for a positive association of fit and overall technology evaluation. In addition, our data suggests the relation between fit and overall evaluation to be asymmetric and non-linear, very similar to a typical convex consumption function. While user mobility did not play an immediate statistically significant role, we found indications of an indirect association: The non-functional characteristic of portability that described the availability of the technology in various mobile use situations turned out to be the most important factor to explain and predict technology requirements and overall evaluation in the current research study.
Grandmotherhood: The Evolutionary Significance of the Second Half of Female Life

Grandmotherhood: The Evolutionary Significance of the Second Half of Female Life. Eckart Voland, Athanasios Chasiotis, and Wulf Schiefenhovel, eds. New Brunswick: Rutgers University Press, 2005. 314 pp.
Role of alternative promoter elements in transcription from the nar promoter of Escherichia coli.

The effects of mutations in the -10, -35, and Fnr box regions of the narGHJI promoter of Escherichia coli were determined by assaying the expression of beta-galactosidase from narG::lacZ fusion plasmids under aerobic and anaerobic conditions. A 1-base change in the -10 hexamer completely abolished expression, whereas a 3-base change to create the consensus TATAAT resulted in significant aerobic as well as anaerobic expression. A mutation in the putative -35 hexamer did not affect anaerobic expression but reduced aerobic expression from the construction with the -10 consensus sequence. A mutation in the Fnr box severely reduced anaerobic expression but did not affect aerobic expression. When the complete 59 region of the nar operon including the NarL box was present, nitrate stimulated both aerobic and anaerobic expression. Stimulation of expression by nitrate occurred in an fnr mutant but not in a narL mutant. We conclude that the rate of transcription of the nar operon is dependent on two distinct modes of transcription. One mode, which occurs at low levels, depends on the -10 and -35 hexamer sequences and is dramatically enhanced by changing the -10 sequence to the consensus TATAAT. The second depends on the -10 and Fnr box sequences but is independent of the -35 sequence. This second mode occurs at a very high level under anaerobic conditions when Fnr is activated and is also enhanced by changing the -10 sequence to the consensus TATAAT. NarL, activated by nitrate, stimulated both modes of transcription, indicating that it does not act through Fnr but that it directly affects the interaction of RNA polymerase with the promoter.
Intact forests provide only weak resistance to a shade-tolerant invasive Norway maple (Acer platanoides L.)

Summary 1 Intact, closed canopied forests appear highly resistant to exotic plant invasions, but there are few experimental studies of this observation. To test this issue and explore the conditions that foster resistance, we experimentally added Norway maple (Acer platanoides L.) seeds to intact forests for 3 years and monitored emergence, survivorship and height growth for 5 years. 2 Seed additions (250 seeds−1 m2) were replicated in situ in combinations of light (deep shade vs. small gaps), soil fertility (NO3 and pH), and variation in soil moisture as influenced by topography (hill slopes vs. flat areas at slope bases) in five eastern deciduous forests in central New York and southern Connecticut. We then parameterized a model with this data to project long-term rates of sapling recruitment. 3 Seedlings had high survival and low growth rates in the deep shade, suggesting that this species readily forms a seedling bank in intact forests. By age 5, annual survivorship reached 93% in deep shade and 98% in small gaps. Median seedling heights were ≤ 10 cm in all treatments after 5 years, though the largest seedlings were markedly taller in gaps. Mean year 5 densities of all experimental seedlings (ages 3–5 years) were 14 seedlings−1 m2 (± 2.4 SE) in the shade and 19 seedlings−1 m2 (± 3.5 SE) in small gaps. 4 While seedlings colonized in all conditions, resistance to invasion varied markedly; resistance was highest in deeply shaded, acidic conditions (pH 6) also significantly increased survivorship, particularly in deep shade. Shading's main effect was to suppress height growth. Overall, the model predicted impressive sapling recruitment; even in deeply shaded, acidic conditions, approximately 1% of seeds emerge and survive to become saplings. 5 Intact forests only weakly resisted A. platanoides colonization, but strongly suppressed its rate of invasion. As such, the frequency of disturbance, though ultimately unnecessary for A. platanoides invasions, will strongly influence its near-term invasiveness. Dispersal limitation and slow stand dynamics appear to be the primary constraints on its current distribution.
Child ADHD severity and positive and negative parenting as predictors of child social functioning: evaluation of three theoretical models.

Objective: Prior research has established links between child social functioning and both parenting and child ADHD severity; however, research examining the way that these variables work together is lacking. The current article aims to test three possible models (main effects, mediation, and moderation) by which ADHD severity and positive and negative parenting on the part of both mothers and fathers may work together to predict child social functioning. Method: In a combined sample of children ages 5 to 11 with and without ADHD (N = 143), multiple regression was used to assess: (a) the main effects of ADHD severity and of positive and negative parenting by both mothers and fathers on child social skill and aggressive behavior; (b) parenting as a potential mediator of the relation between ADHD severity and child social skill and aggressive behavior; and (c) ADHD severity as a potential moderator of the relation between parenting and child social skill and aggressive behavior dependent variables. Results: Significant main effects of both ADHD severity and parenting on child social skill and aggression were found. There was some evidence to support parenting (particularly negative parenting) as a mediator of the relation between ADHD severity and child social skill and aggression. There was no evidence of significant moderational effects. Conclusion: Parenting and ADHD severity are independently associated with child social skill and aggressive behavior. To the extent that these associations are causal, multimodal treatment targeting both symptom reduction and improved parenting may be especially effective for the treatment of social problems related to childhood ADHD. Furthermore, evidence for parenting as a mediator of the relation between ADHD severity and child outcomes suggests that changes in child symptoms may also improve parenting practices, thus leading to improved child outcomes. ( J. of Att. Dis. 2010; XX(X) 1-XX)
Scheduled Feedforward Control of Superheat Through Hardware-in-the-Loop Load Emulation

Variable speed refrigeration systems have the potential for improved energy savings compared to conventional on-off systems. A single-input-single-output (SISO) control structure does not adequately regulate control parameters due to strong coupling inherent to the vapor compression cycle (VCC). With the use of an electronic expansion valve (EEV) a feedforward control configuration may be implemented to remove the effects of compressor speed changes on evaporator superheat, thus allowing better regulation during transients. Due to the nonlinearity of the VCC a scheduled feedforward compensator is proposed to effectively reject a compressor disturbance over the wide range of operating conditions typically experienced by variable speed systems. The proposed control structure allows superheat regulation at a low level without risking compressor damage, therefore helping maximize system efficiency. This paper presents experimental results obtained through load emulation. This is a novel approach which performs a task similar to the automotive dynamometer, where various size loads and environmental conditions may be placed on a VCC through an on-line experimental simulation.Copyright © 2010 by ASME
Construction and characterization of isogenic O-antigen variants of Salmonella typhi

A 7.5 kb KpnI-generated fragment, from within the rfb cluster of Salmonella typhimurium LT2 that encodes abequose synthase (the rfbJ gene) which is necessary for O4 antigen synthesis, and flanking sequences, was inserted into a suicide vector. Using allelic exchange techniques, these rfb sequences of S. typhimurium were integrated into the rfb clusters of wild-type Salmonella typhi Vi-positive strain ISP 1820 (i.e. serotype O9,12; Vi+; H-d), S. typhi Vinegative strain H400 (i.e. serotype O9,12; Vi-; H-d), and a double aro mutant of S. typhi ISP 1820, strain CVD 906, resulting in the isolation of strains H325, H404 and CVD 906-O4, respectively. Immunoblot analysis of lipopolysaccharide (LPS) purified from H325, H404 and CVD 906-O4 demonstrated that these strains express the O4 antigen (an abequose residue) in place of the O9 antigen (a tyvelose residue) in the LPS molecule. Hence, the serotype of H325 is O4,12; Vi+; H-d and the serotype of H404 is O4,12; Vi-; H-d. DNA hybridization analysis of chromosomal DNA from H325, H404 and CVD 906-O4 confirmed that a precise recombination event within sequences flanking rfbSE of S. typhi (which encodes the enzymes necessary for cytidine diphosphate-tyvelose synthesis) resulted in replacement of rfbSE with rfbJ (which encodes abequose synthase and is necessary for O4 synthesis) of S. typhimurium in strains H325, H404 and CVD 906-O4. The resistance of each strain to the bactericidal effects of guinea-pig serum (GPC) was assessed. Whereas ISP 1820, H325 and H404 exhibit similar resistance patterns in GPC, strain H400 is sensitive to the bactericidal effects of GPC.(ABSTRACT TRUNCATED AT 250 WORDS)
A Further Examination of Appraisal Data and the Potential Bias in Real Estate Return Indexes

Recent articles by Giliberto [2] and Geltner [1] examine the biases inherent in the use of appraisal data in real estate performance measurement. This note takes another look at the direction and magnitude of any bias in holding period returns. Using appraisal data from a commingled real estate fund, we show that in actual application the size of the holding period return bias can be quite small and this bias may have no appreciable effect on real estate return indexes.
CHARACTERISTICS OF A HEAVY-ION DETECTION SYSTEM

Abstract The characteristics of a heavy-ion detection system are considered. The detection of the heavy ions is achieved by collecting the ions (which must be radioactive) in stacked foils and then measuring the radioactivity of the foils. Although the system is limited to detecting radioactive isotopes, ten interesting reactions can be investigated: four neutron stripping reactions, (C12, C11), (N14, N13), (O16, O15) and (F19, F18); four proton pickup reactions, (B10, C11), (C12, N13), (N14, O15) and (O16, F17); and two nucleon interchange reactions, (B11, C11) and (N14, O14). The energy resolution of the system varies from 0.7 to 0.4 MeV (full-width-at-half-maximum). The outstanding feature of the system is its high discrimination against the detection of stable isotopes. A system which has been constructed is described.
Rheology and curing kinetics of fumed silica/cyanate ester nanocomposites

A low-viscosity bisphenol E cyanate ester (BECy) monomer was combined with fumed silica with average primary particle diameters of 12 and 40 nm to form high-temperature adhesives with processability at ambient temperatures. Rheological evaluation revealed that for silica loadings below 15 vol%, suspensions of both particle sizes exhibited shear thinning and thixotropic behavior. Samples with high silica loadings (>15 vol%) of 40-nm silica also showed intense shear thickening at shear rates above 10 s−1. Thixotropy was most pronounced for the 12-nm silica, but the formation of a gel was slow, indicating that the polar nature of the BECy monomer was responsible for disrupting hydrogen bonds between silica particles. Rheokinetic evaluation of catalyzed samples showed that increasing silica content reduced gel time and increased gel viscosity, and this effect was most pronounced for the 12-nm silica. Differential scanning calorimetry confirmed that the silica's hydroxyl groups have a minor catalytic effect on the polymerization kinetics, such that the activation energies of the catalyzed suspensions were decreased with increased nanoparticle loading and decreased particle size. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
The mass spectra of some phenanthro (9,10‐d) heterocycles

The mass spectra of six phenanthro(9,10-d)-oxazoles, thiazoles and imidazoles are reported. The decompositions of the phenanthro(9,10-d) derivatives resemble the corresponding benzo heterocycles. A C13H7 fragment was found to be characteristic of these phenanthro compounds. Deuterium labeling was used to show that there is no correlation between the formation of the C13H7 from the phenanthro compounds and the C13H9 observed in the spectra of 4,5-diphenyl substituted heterocycles.
Seeing the {closed+camouflage+natural=forest} for the trees: Rapid scene categorization can be mediated by conjunctions of global scene properties

Thanks Grateful thanks to Antonio Torralba, Molly Potter and Josh Tennenbaum for suggestions and discussion. Object annotations using LabelMe. MRG is supported by NSF-GRF. mrgreene@mit.edu oliva@mit.edu http://cvcl.mit.edu Ranking Results "No attempt was made here to fomulate an operational defi nition of globality of visual features which enable precise predictions about the course of perception of realworld stimuli. What is suggested in this paper is that whatever the perceptual units are, the spatial relationships among them is more global than the structure within them.....Thus, I am afraid that operational measures for globality will have to patiently await the time that we have a better idea of how a scene is composed into perceptual units" Navon, 1977. A natural scene. "Wintery forest road"
Mdm2's Dilemma: To Degrade or To Translate p53?

In this issue of Cancer Cell , Gajjar et al. provide insight into how Mdm2 can both inhibit and enhance p53 activity. In the basal setting, Mdm2 binds p53 and promotes p53 degradation. Under stress conditions, ATM-dependent phosphorylation of Mdm2 results in its recruitment to p53 mRNA, thereby stimulating p53 translation.
Doxycycline binding to plasma albumin of several species

The affinity of doxycycline for crystalline plasma albumin fraction V, originating from sheep, dogs, cats, cows, pigs and humans, was evaluated by means of double-reciprocal and Scatchard plots. Mathematical modelling and weighted least-squares non-linear regression analysis of each Scatchard plot identified one binding component characterized by one high affinity binding site, and a second component attributed to non-specific binding to albumin. Association constants for this binding site ranged from 38,471 +/- 13,369 (SEM) l/mol for the interaction of doxycycline with ovine albumin to 6405 +/- 2375 l/mol for the interaction of doxycycline with human albumin. Statistical evaluation of the results suggested slight species-related differences in the values of association constants. Diphenylhydantoin, phenobarbital or carbamazepine did not displace doxycycline from binding sites on bovine albumin.
Sodium phosphate preparation for colonoscopy: onset and duration of bowel activity.

Abstract Background: Two doses of sodium phosphate are recommended for colonic cleansing before colonoscopy. Patients need information about the onset and duration of activity of the preparation. This study was designed to develop practical prescribing information to patients to reduce anxiety concerning bowel accidents. Methods: Two hundred patients were requested to take a liquid diet the day before colonoscopy, to take 45 mL sodium phosphate with water or juice the evening before and the morning of the procedure, and to complete a questionnaire. Results: Bowel activity began 1.7 hours (range 0.5 to 13) after the first dose and continued for 4.6 (1 to 14) hours. For the second dose the time to onset was 0.7 hours (0.25 to 4), and bowel activity continued for 2.9 hours (0.5 to 6.5). Bowel activity was completed 4 hours after ingestion of the second dose in 83% of patients and within 5 hours in 87%. Three of 200 patients reported the need for bowel evacuation during transit. Conclusions: The activity from the second dose of sodium phosphate starts and ends sooner than that from the first dose. When advising patients on when to take the second dose of sodium phosphate, 4 hours for most and 5 hours for those with long commutes, should provide adequate time for almost all patients to avoid bowel activity during travel. (Gastrointest Endosc 1999;50:811-3.)
Temporal stability of the urinary proteome after kidney transplant: more sensitive than protein composition?

The temporal urinary proteome was examined in 4 groups of individuals in order to determine the temporal stability of diverse individuals with apparently good kidney health. The groups consisted of (1) healthy volunteers at zero time, 1 and 6 months, (2) kidney donors before and after surgery, (3) recipients immediately after surgery, and (4) successful kidney transplant recipients from 1 month to 4 years after transplant. Proteins were detected by reverse phase extraction of urine followed by MALDI-TOF profile and by iTRAQ analysis. Unusual components of the MALDI-TOF profiles found only in transplant subjects occurred at m/z = 3370, 3441 and 3385 (human neutrophil defensins), 4303, 10350, and 11732 (β-2 microglobulin, B2M). The peaks at m/z = 4303 and 11732 were also quite intense among kidney donors following surgery. The peaks at m/z = 4303 and 10350 in transplant recipients were associated with higher serum creatinine. Several additional proteins detected by iTRAQ were up-regulated in a manner that c...
Parallel recombinative simulated annealing: a genetic algorithm

Abstract This paper introduces and analyzes a parallel method of simulated annealing. Borrowing from genetic algorithms, an effective combination of simulated annealing and genetic algorithms, called parallel recombinative simulated annealing, is developed. This new algorithm strives to retain the desirable asymptotic convergence properties of simulated annealing, while adding the populations approach and recombinative power of genetic algorithms. The algorithm iterates a population of solutions rather than a single solution, employing a binary recombination operator as well as a unary neighborhood operator. Proofs of global convergence are given for two variations of the algorithm. Convergence behavior is examined, and empirical distributions are compared to Boltzmann distributions. Parallel recombinative simulated annealing is amenable to straightforward implementation on SIMD, MIMD, or shared-memory machines. The algorithm, implemented on the CM-5, is run repeatedly on two deceptive problems to demonstrate the added implicit parallelism and faster convergence which can result from larger population sizes.
Shear characterization of unidirectional composites with the off-axis tension test

The influence of end constraints on accurate determination of the intralaminar shear modulus G(12) from an off-axis tension test is examined both analytically and experimentally. The Pagano-Halpin (1968) model is employed to illustrate that, when the effect of end constraints is properly considered, the exact expression for G(12) is obtained. When the effect of end constraints is neglected, expressions for the apparent shear modulus G(12)-asterisk and apparent Young's modulus Exx-asterisk are obtained. Numerical comparison for various off-axis configurations and aspect ratios is carried out using typical material properties for graphite/polyimide unidirectional composites. It is demonstrated that the end-constraint effect influences accurate determination of G(12) more adversely than it affects the laminate Young's modulus E(xx) in the low off-axis range. Experimental results obtained from off-axis tests on unidirectional graphite/polyimide specimens confirm the above. Based on the presented analytical and experimental evidence, the 45-deg off-axis coupon is proposed for the determination of the intralaminar shear modulus G(12).
Lipoprotein as a regulator of starch synthesizing enzyme activity

Abstract Amylose precipitating factor, a lipoprotein, functions as a regulator of in vitro activity of glycogen/starch phosphorylase and of A/UDPglucose glucosyl-transferase. The results suggest that this lipoprotein could act to stimulate the in vivo production by phosphorylase of long, linear glucans (amylose) from the short chain precursors. The lipoprotein also appears to switch A/UDPglucose glucosyltransferase from the elongation of branched glucan molecules (amylopectin and glycogen) to the elongation of linear glucans (amylose).
Neutron Fluence and Electric Field Strength Dependencies of the Rate of Volume Damage Introduction in Silicon P-N Junctions

The anamolous behavior of neutron-induced defect clusters in the high field space-charge region of silicon p-n junctions is investigated. The space-charge region recombination current variation with neutron fluence and the junction electric field strength present during irradiation is examined and an electric field strength dependence for the defect clusters is found to exist. The space-charge region rate of volume damage introduction is observed to be a function of both neutron fluence and the junction electric field strength present during irradiation. An empirical expresion for the dependence of the rate of volume damage introduction on fluence and junction field strength present during irradiation is developed. Possible mechanisms for the observed field dependence are discussed.
Thyroid of the coelacanth, Latimeria chalumnae Smith.

THE thyroid of bony fishes is composed usually of thyroid follicles more or less scattered in the ventral pharyngeal area, although two additional variations in thyroid structure have been found in teleosts. Earlier reports have described the aggregation of thyroid follicles to form a discrete thyroid mass lacking a fibrous capsule, so that additional follicles located elsewhere are not uncommon. It was later revealed that functional thyroid follicles may be scattered not only in the pharyngeal region but also heterotopically in areas such as the lymphoidal pronephric rudiment (head kidney). With the capture in the Comoros of a small (85 cm) living Latimeria chalumnae on March 22, 19721, it became feasible for the first time to define the thyroidal structure and the relationship of this gland in terms of osteichthyean or tetrapod characteristics.
Musicians' Ratings of Good versus Bad Vocal and String Performances

This study continues a line of research attempting to ascertain the focus of musicians' attention when listening to music. It is the fifth study in a series structured to determine whether musicians demonstrate consistent listening patterns across excerpts intentionally designed to be perceived as good and bad performances. Soprano, tenor, violin, and cello excerpts varied considerably in intonation and tone quality and, to a lesser extent, in other performance aspects. In this study, 48 music students were asked to rate excerpts on traditional performance evaluation rating scales (phrasing/expression, intonation, rhythm, dynamics, tone quality) and give an overall rating. Results indicated that musician listeners consistently discriminated between the good and bad performances across all rating scales. Intonation was identified as the element most in need of improvement in performances. Significant differences were found also between the four timbres and the accompaniment conditions. Results of acoustica...
The unique OMI HCHO/NO2 feature during the 2008 Beijing Olympics: Implications for ozone production sensitivity

In preparation of the Beijing Summer Olympic and Paralympics Games, strict controls were imposed between July and September 2008 on motor vehicle traffic and industrial emissions to improve air quality for the competitors. We assessed chemical sensitivity of ozone production to these controls using Ozone Monitoring Instrument (OMI) column measurements of formaldehyde (HCHO) and nitrogen dioxide (NO2), where their ratio serves as a proxy for the sensitivity. During the emission controls, HCHO/NO2 increased and indicated a NOx-limited regime, in contrast to the same period in the preceding three years when the ratio indicates volatile organic carbon (VOC)-limited and mixed NOx-VOC-limited regimes. After the emission controls were lifted, observed NO2 and HCHO/NO2 returned to their previous values. The 2005-2008 OMI record shows that this transition in regimes was unique as ozone production in Beijing was rarely NOx-limited. OMI measured summertime increases in HCHO of around 13% in 2008 compared to prior years, the same time period during which MODIS vegetation indices increased. The OMI HCHO increase may be due to higher biogenic emissions of HCHO precursors, associated with Beijing's greening initiative for the Olympics. However, NO2 and HCHO were also found to be well-correlated during the summer months. This indicates an anthropogenic VOC contribution from vehicle emissions to OMI HCHO and is a plausible explanation for the relative HCHO minimum observed in August 2008, concurrent with a minimum in traffic emissions. We calculated positive trends in 2005-2008 OMI HCHO and NO2 of about +1 x 10(exp 14) Molec/ square M-2 and +3 x 10(exp 13) molec CM-2 per month, respectively. The positive trend in NO2 may be an indicator of increasing vehicular traffic since 2005, while the positive trend in HCHO may be due to a combined increase in anthropogenic and biogenic emissions since 2005.
Absconding with the Chaperone: Essential Cyclophilin–Gag Interaction in HIV-1 Virions

Perhaps the greatest significance of these studies with HIV-1 CA is the contribution they make to our understanding of the role of CyPs. A growing collection of data indicates that a primary role of CyPs is to mediate protein–protein interactions. As a high-affinity complex with cyclosporine A, CyP creates a composite surface that inhibits calcineurin (Schreiber and Crabtree 1992x>. Schreiber, S.L and Crabtree, G.R. Immunology Today. 1992; 13: 136–142Abstract | Full Text PDF | PubMed | Scopus (1560)See all ReferencesSchreiber and Crabtree 1992). The Drosophila CyP NinaA forms a stable complex with the major isoform of rhodopsin that is required for this photoreceptor protein to exit the endoplasmic reticulum (Baker et al. 1994x>. Baker, E.K, Colley, N.J, and Zuker, C.S. EMBO J. 1994; 13: 4886–4895PubMedSee all ReferencesBaker et al. 1994). Now it has been demonstrated that HIV-1 replication requires the formation of a stable complex between CA and CyPA (4x>. Braaten, D, Franke, E.K, and Luban, J. J. Virol. 1996; 70: 3551–3560PubMedSee all References, 6x>. Franke, E.K, Yuan, H.E.H, and Luban, J. Nature. 1994; 372: 359–362Crossref | PubMed | Scopus (542)See all References, 15x>. Thali, M, Bukovsky, A.A, Kondo, E, Rosenwirth, B, Walsh, C.T, Sodroski, J, and Gottlinger, H.G. Nature. 1994; 372: 363–365Crossref | PubMed | Scopus (475)See all References).The first CyPs to be cloned were simple molecules consisting of a core CyP domain and, at most, terminal extensions that direct subcellular localization. Recently, CyP family members have been identified which are components of large macromolecular complexes and possess several well-characterized motifs. Nup358/RanBP2, the largest nuclear pore component, constitutes the most dramatic example; in addition to a cyclophilin-homologous domain, this protein possesses a leucine-rich region, Ran-binding sites, nucleoporin-characteristic repeats, and zinc-fingers (16x>. Wu, J, Matunis, M.J, Kraemer, D, Blobel, G, and Coutavas, E. J. Biol. Chem. 1995; 270: 14209–14213Crossref | PubMedSee all References, 17x>. Yokohama, N, Hayashi, N, Seki, T, Pante, N, Ohba, T, Nishii, K, Kuma, K, Hayashida, T, Miyata, T, Aebi, U, Fukui, M, and Nishimoto, T. Nature. 1995; 376: 184–188Crossref | PubMedSee all References). The identification of proteins such as this supports the contention that CyP functions as a modular protein–protein interaction cassette reminiscent of other protein subunits such as the Src homology domains.
Intraplate volcanism due to convective instability of stagnant slabs in the mantle transition zone

The study of volcanism can further our understanding of Earth's mantle processes and composition. Continental intraplate volcanism commonly occurs above subducted slabs that stagnate in the Mantle Transition Zone (MTZ), such as in Europe, eastern China, and western North America. Here, we use two-dimensional numerical models to explore the evolution of stagnant slabs in the MTZ and their potential to sustain mantle upwellings that can support volcanism. We find that weak slabs may go convectively unstable within tens of million years. Upwellings rise out of the relatively warm underbelly of the slab, are entrained by ambient-mantle flow and reach the base of the lithosphere. The first and most vigorous upwellings rise adjacent to lateral heterogeneity within the slab. Ultimately, convective instability also acts to separate the compositional components of the slab, harzburgite, and eclogite, from each other with harzburgite rising into the upper mantle and eclogite sinking into the lower mantle. Such a physical filtering process may sustain a long-term compositional gradient across the MTZ.
A Method for Hierarchical Clustering of a Matrix of a Thousand By a Thousand 1

Most hierarchical clustering methods are limited to relatively small matrices. On the other hand, if personality types exist, there are probably many of them. Consequently, a method is needed for clustering hierarchically the interrelationships between many persons, as represented in a matrix of a thousand by a thousand. This paper develops and illustrates such a method.
From Design for Dominance to Design for Dialogue

The increasing complexity of the network society is the result of a particular approach to design: that of mastery, control, ease of use and interconnectedness. The author analyzes this design approach for its negative and positive aspects, which he labels as ‘designing for dominance’ and ‘designing for dialogue’, respectively. Both of these aspects are inherent (and in constant opposition) in all designed learning objects and environments. He argues that the ‘dominant’ aspect of design, as influenced by cognitive science, obscures or minimizes the possibility of learner dialogue in favor of empirical knowledge. Design for dominance eliminates the educative potential of chance and ambiguity in its design process, while it emphasizes complete control over the elements of production. Overly dominant designs are ill-suited to account for higher-order thinking skills, which can only result from more dialogical designs, in service of critical reflection, withholding judgment and productive ambiguity. The autho...
Lipoproten synthesis and fatty acid mobilization in rats after partial hepatectomy

Abstract 1. 1. Plasma protein and lipoprotein synthesis was studied in whole animals 6 h and 24 h after partial hepatectomy. Synthesis of very low density lipoproteins was increased while the synthesis of other plasma proteins was decreased. These data suggest that decreased formation of very low density lipoproteins can not be responsible for the fatty liver observed after partial hepatectomy. 2. 2. Peripheral fatty acid mobilization was studied by the in vivo labeling of epididymal fat pads. It was shown that in partially hepatectomized and shamoperated animals fatty acid mobilization was greater than in the non operated controls, although fatty livers occurred only in the partially hepatectomized rats. 3. 3. Fatty acids were preferentially incorporated into triglycerides rather than into phospholipids and this may be a factor leading to the accumulation of triglyceride in the liver.
Luminescence optical tomography of dense scattering media

Using a set of coupled radiation transport equations, we derive image operators for luminescence optical tomography with which it is possible to reconstruct concentration and mean lifetime distribution from information obtained from dc and time-harmonic optical sources. Weight functions and detector readings were computed from analytic solutions of the diffusion equation and from numerical solutions of the transport equation by Monte Carlo methods. Detector readings were also obtained from experiments on vessels containing a balloon filled with dye embedded in an Intralipid suspension with dye in the background. Image reconstructions were performed by the conjugate gradient descent method and the simultaneous algebraic reconstruction technique with a positivity constraint. A concentration correction was developed in which the reconstructed concentration information is used in the mean-lifetime reconstruction. The results show that the target can be accurately located in both the simulated and the experimental cases, but quantitative inaccuracies are present. Observed errors include a shadowing effect in regions that have the lowest weight within the inclusion. Application of the concentration correction can significantly improve computational efficiency and reduce error in the mean-lifetime reconstructions.
ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS) IN PEDIATRIC HEMOPHILIACS

Three of 35 U.S. children (<18 years old) with AIDS reported to the Centers for Disease Control (CDC) as of December 1983 had hemophilia. We summarize these and 2 European pediatric AIDS patients with hemophilia, reported to CDC. All 5 patients were white and male; ages ranged from 9-16 years. Four patients had severe hemophilia A; 1, moderate hemophilia B. Two cases resided in New York; 1, in Pennsylvania; the European cases were Spanish and siblings. Four patients presented with fever and weight loss; all had pulmonary symptoms. All cases had laboratory findings consistent with AIDS and had opportunistic infections (OI) including Pneumocystis carinii pneumonia, systemic cytomegalovirus, and systemic fungal infections. Three patients (60%) have died. None had other known risk factors for AIDS or immunosuppressive therapy. The hemophilia B patient received 2 units of whole blood in 1982 and no other blood products. Factor VIII was the only blood product received by both U.S. hemophilia A patients in the past 5 years. The prevalence of hemophilia in pediatric AIDS patients is much higher than its estimated population prevalence (1 in 10,000), indicating that hemophilia is a risk factor for AIDS. AIDS may occur in those receiving only factor or only whole blood therapy. Pediatricians should consider AIDS in any patient with hemophilia and unexplained weight loss, fever, or OI. To help further clarify the role of blood products in AIDS transmission, they should inquire about all product usage and other AIDS risk factors.
Restricted and Repetitive Behaviors and Psychiatric Symptoms in Youth with Autism Spectrum Disorders.

Abstract Children with autism spectrum disorders (ASD) are at high risk for co-occurring psychiatric disorders. Previous research has suggested that restricted and repetitive behaviors (RRB) are associated with symptoms of co-occurring psychiatric disorders in individuals with ASD, but this relationship is not well understood. The current study investigated the relationship between RRB and co-occurring psychiatric symptoms, including depressive, anxiety, attention-deficit hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) symptoms, while considering the role of level of functioning. Participants were 72 parents of youth diagnosed with an ASD (ages 5–17). They completed the Social Communication Questionnaire (SCQ), the Repetitive Behavior Scale-Revised (RBS-R), an abridged version of the Child Symptom Inventory-4 (CSI-4) and the Conceptual domain of the Adaptive Behavior Assessment System, 2nd Edition (ABAS-II). Results indicated that RRB do predict psychopathology. Ritualistic and sameness behavior is predictive of anxiety, depression and ODD while stereotypy is predictive of ADHD. Restricted interests were a negative predictor of depression. Level of functioning moderated the relationship between self-injurious behavior (SIB) and both anxiety and depressive symptoms as well as the relationship between ritualistic and sameness behavior and depressive symptoms. Understanding the relationship between RRB and psychiatric symptoms could help clarify the presentation of ASD phenotypes as well as etiological variables.
Interfaces of polyphenylene sulphide-to-metal joints

High-temperature polyphenylene sulphide (PPS) film was deposited on the surface of cold-rolled, stainless and galvanized steels by slurry coating in N2 and O2 gases at 350°C. The value of the interfacial PPS/steel bond strength depended primarily on the species of sulphur-related iron compounds formed as reaction products at the interfaces. The order of these reaction products, which play an important role in developing bond strength, was Fe2(SO4)3 >FeSO4 >FeS. In conctrast, the conversion of ZnS, formed at the PPS/galvanized steel interfaces, into ZnSO4 led to a catastrophic loss of bond strength.
Explaining crime in developing countries: The need for a case study approach

The relationship between crime and development typically has been investigated within the theoretical umbrella of three dominant frameworks (modernization, underdevelopment, routine activities) and by the analysis of cross-national, statistical correlations between developed and developed countries. We outline the empirical, methodological, conceptual and theoretical weaknesses of these studies. The categories developed and developing are invalid when studying crime and change and the defects of existing approaches can only be overcome by a case study approach to the relationships of patterns of crime in different countries.
Some characteristics of reduced leaf photosynthesis at midday in maize growing in the field

Abstract Maize was grown in the high-radiation arid summer environment of Davis, California, and its leaf photosynthetic rate was measured over diurnal courses on cloudless days with the leaf held perpendicular to the sunlight. On days of high atmospheric vapor pressure deficit (VPD), leaf photosynthesis reached a maximum in the late morning and then decreased gradually as the day progressed, though the soil was well irrigated. When CO2 concentration in the measurement chamber was raised to about 1000 μmol mol−1, photosynthesis was enhanced, but more in the afternoon than in the morning. As a result, rates measured at high CO2 in the morning and afternoon were essentially the same. There was also no difference in the curves of photosynthetic rate (A) versus intercellular CO2 concentration (Ci) for the morning and afternoon. Hence, photosynthetic capacity was similar for the two periods and there was no evidence of photoinhibition by the high photosynthetic photon flux density at noon. Further, Ci and photosynthetic rates A measured over a range of photon flux density were lower in the afternoon than in the morning. These results indicate that A at noon and early afternoon was more limited than in the morning by epidermal conductance (mostly stomatal). On a day of low VPD, however, midday depression in A and epidermal conductance were not evident for the well-irrigated plants. Without irrigation and with leaves at a lower midday water potential, midday reduction in conductance and A was much more marked, beginning late in the morning. Epidermal conductance of maize grown in the field in Davis is are not sensitive to VPD. Therefore, the midday reduction in conductance and A was more likely the result of low leaf water potential caused by high transpiration rates.
EFFECT OF LIVER DAMAGE ON PLASMA FFA RESPONSE TO EPINEPHRINE.

SummaryThree groups of male Sprague-Dawley rats, control, partially hepatectomized and chronically poisoned with CCl4, were injected with 1 mg/kg epinephrine in oil. Plasma FFA and blood glucose were measured over a 4-hour post-injection period. Control animals showed the usual hyperglycemic and hyperlipemic response to epinephrine within the first hour after injection. Blood glucose and FFA were back to pre-injection levels at 4 hours. After partial hepatectomy, pre-injection blood levels of glucose were normal but FFA concentration was elevated. The hyperglycemic response to epinephrine was normal but the FFA response was markedly altered. A further elevation in plasma FFA was observed after 1/2 hour and these high levels persisted during the entire 4-hour post-injection period. Chronic CCl4 induced liver damage elicited a different kind of epinephrine response. There was an abnormally sustained hyperglycemia during the 4-hour post-injection period but the plasma FFA never showed any elevation above pre...
Profiles in Science for Science Librarians: Wallace Broecker

Wallace Broecker is thought to be one of the greatest living geoscientists. During his fifty-plus year career at the Lamont-Doherty Earth Observatory at Columbia University in Palisades, New York, he has been very prolific and is a highly cited geoscientist. Broecker is probably best known for his theory of global ocean circulation, a “great ocean conveyor” that transports a significant amount of heat around the globe that can also trigger abrupt shifts in world climate. He unintentionally coined the phrase global warming in the title of one of his many papers and is very active to this day. His diverse research areas include paleoclimatology, environmental science, ocean chemistry, isotope geochemistry, and geochronology. Broecker is the winner of most of the awards in his field, including the Crafoord Prize in Geosciences.
A role for the endoplasmic reticulum protein retrotranslocation machinery during crosspresentation by dendritic cells.

Summary Crosspresentation of exogenous antigens (Ags) to CD8 + T cells by dendritic cells generally requires their entry into the cytosol. Here we show that both soluble and phagocytosed extracellular Ags accessed the cytosol via molecular components required for endoplasmic reticulum (ER)-associated degradation (ERAD). Exogenous Pseudomonas aeruginosa Exotoxin A, which inhibits protein translocation from the ER to the cytosol, abrogated crosspresentation. Exotoxin A also prevented the transporter associated with antigen processing (TAP) inhibitor, ICP47, from entering the cytosol and blocking TAP-mediated peptide transport. In an in vitro model of retrotranslocation, the AAA ATPase p97, an enzyme critical for ERAD, was the only cytosolic cofactor required for protein export from isolated phagosomes. Functional p97 was also required for crosspresentation but not conventional presentation. Thus, crosspresentation appears to result from an adaptation of the retrotranslocation mechanisms involved in the degradation of misfolded ER proteins.
Interaction between heat shock and interleukin 6 stimulation in the acute‐phase response of human hepatoma (HepG2) cells

Two characteristic elements of the acute-phase response are an altered pattern of circulating hepatic proteins and fever. Whereas a fever-induced heat shock response could affect expression of acute-phase proteins in the liver, the effects of a modest temperature increase on protein secretion in interleukin-6 (IL-6)–stimulated HepG2 cells were investigated. The response of HepG2 cells to IL-6 stimulation was significantly affected by heat treatment at 40°C. Albumin secretion rates, which were reduced by a factor of 2 in response to either heat shock or IL-6 stimulation alone, were down-regulated by a factor of 4 when IL-6 was administered simultaneously with a continuous 40°C heat shock. IL-6–induced fibrinogen up-regulation was significantly reduced by heat treatment (P .10). Unexpectedly, heat shock at 40°C induced a fivefold up-regulation of haptoglobin production in the absence of IL-6. Simultaneous heat shock and IL-6 stimulation caused a synergistic enhancement of haptoglobin expression, with secretion rates increasing up to 30-fold compared with unstimulated control cells. For all three proteins, the interaction between temperature and IL-6 concentration was statistically significant (P < .001). Heat treatment resulted in significant alterations of both the kinetics and sensitivity of IL-6–induced protein synthesis, suggesting a major modification of the mechanism of acute-phase protein regulation at 40°C. In summary, the data show that heat shock can significantly modulate the pattern of acute-phase protein expression and that fever may be an important regulatory factor in the acute-phase response.